DEVELOPMENT OF ATMOSPHERIC PLASMA JET
FOR PORK SKIN TREATMENT
BY
KAMONCHANOK DEEMEK
A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF
THE REQUIREMENTS FOR THE DEGREE OF MASTER OF
ENGINEERING (ENGINEERING TECHNOLOGY)
SIRINDHORN INTERNATIONAL INSTITUTE OF TECHNOLOGY
THAMMASAT UNIVERSITY
ACADEMIC YEAR 2016
DEVELOPMENT OF ATMOSPHERIC PLASMA JET
FOR PORK SKIN TREATMENT
BY
KAMONCHANOK DEEMEK
A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF
THE REQUIREMENTS FOR THE DEGREE OF MASTER OF
ENGINEERING (ENGINEERING TECHNOLOGY)
SIRINDHORN INTERNATIONAL INSTITUTE OF TECHNOLOGY
THAMMASAT UNIVERSITY
ACADEMIC YEAR 2016
ii
Abstract
DEVELOPMENT OF ATMOSPHERIC PLASMA JET FOR PORK SKIN
TREATMENT
by
KAMONCHANOK DEEMEK
Bachelor of Science, King mongkut's institute of technology ladkrabang, 2014
Master of Engineering (Engineering Technology), SIIT, Thammasat University, 2016
This study aims to develop the plasma jet for animal skin treatment. There are three
designs of atmospheric plasma jet system consider. The impacts of control parameters,
including applied voltage, applied frequency, and flow rate of argon gas is also
investigated in order to optimize the performance of the plasma jet. The power
discharge, plasma plume length and the optical emission spectrum are used in the
performance optimization. The results show that the similar trends are observed from
those 3 designs considered, in which the discharge power increases with the increase of
supplied voltage and frequency with 95% confidential based on ANOVA analysis.
However, it is found that the discharge power does not depend on the Argon flow rate.
It is also found that plasma plume length has the correlation with applied voltage, the
frequency and flow rate. In addition, the OES spectrum shows that the trend line of
spectrum will increase if the applied voltage or the frequency increase. Furthermore the
trend line of spectrum also show that the flow rate 2 liter/minute yield the best
performance.
Keywords: Atmospheric pressure plasma , Plasma jet, Power discharge
iii
Acknowledgements
At first I would like to express my sincere thanks to my thesis advisor,
deeply grateful to Associate Professor Dr. Thawatchai Onjun for his valuable helping
and supporting. I am most grateful for his bearing teaching and advising me throughout
the course of this research. Without all the support that I have always received from
him I would not have achieved this graduation and this thesis would not have been
completed.
Besides my advisor, I would like to acknowledge and pay my sincere
thanks my committee members, Associate Professor Dr. Paiboon Sriarunothai,
Associate Professor Dr. Shinsuke Mori and Dr. Udom Sae-Ueng for serving as my
committee member and alway helping provide an useful advice.
My sincere thanks also goes to Dr. Nopporn Poolyarat for always helping,
supporting by giving an area for make this experimental. Also Dr. Puwanan chumthong
who always guiding and helping me until the end of this period.
I would also like to acknowledge the Plasma Fusion Research Unit group
members for all helping, encouraging and supporting me.
I gratefully acknowledge the scholarship received from TAIST-Tokyo tech.
I greatly appreciate all teachers for their patient instruction and my classmates for their
endless friendship and encouragement. I really appreciate all the kind support from the
program staff during my entire program of study.
Last but not the least, for my beloved family and my lovely friends. I am
very appreciate for all their supporting, loving and believing in myself. Also my friends
who were encourage me until the end of this research period.
Ms. Kamonchanok Deemek
iv
Table of Contents
Chapter Title Page
Signature Page i
Acknowledgements ii
Abstract iii
Table of Contents iv
List of Figures (if any) v
List of Tables (if any) vi
1 Introduction 1
1.1 Introduction 1
1.2 Statement of problem 3
1.3 Scope of study 4
1.4 Significance of the study 4
2 Literatures Review 5
2.1 Basic and Fundamentals of plasma 5
2.1.1 Plasma criteria 7
2.2 Generation of plasma 8
2.2.1 Ionization process 9
2.3 Plasma categories 10
2.3.1 Thermal Equilibrium Plasma or Thermal Plasma 12
2.3.2 Non Thermal Equilibrium Plasma or Non Thermal plasma 12
2.4 Atmospheric pressure plasma jet 14
2.5 Free radicals 15
2.6 Design of atmospheric plasma jet 17
2.7 Current research of atmospheric plasma jet 19
v
2.8 Brief information on the animal skin 22
2.8.1 Information about skin 22
2.8.1.1 Porcine skin 23
2.8.1.2 Structure of porcine skin 24
2.8.1.3 Structure of the cell membrane 25
2.9 Wettability 25
3 Development of atmospheric plasma jet 27
3.1 Three designs of plasma jet and power supply system 27
3.2 Structure of atmospheric plasma source APPJ 29
3.3 Parameters to identify the performance of plasma jet 32
3.3.1 Measurement of power discharge 32
3.3.2 Measurement of plasma plume length 34
3.3.3 Optical Emission spectroscopy characteristic 34
4 Results and discussion 35
4.1 Discharge power of plasma jet 35
4.1.1 Discharge power of design 1 35
4.1.2 Discharge power of design 2 36
4.1.3 Discharge power of design 3 37
4.2 Plasma plume length of plasma jet 37
4.2.1 Plasma plume length of designl 1 38
4.2.2 Plasma plume length of design 2 39
4.2.3 Plasma plume length of design 3 40
4.3 Optical Emission Spectroscopy of plasma jet 41
4.4 Impact of plasma jet on pork skin 42
5 Conclusions and Recommendations 44
5.1 Conclusions 44
5.2 Recommendations 44
References 45
Appendix
vi
List of Tables
Tables Page
2.1 The differentiation between plasma state and gas state 6
2.2 The major characteristics between Thermal plasma and
Non- thermal plasma 11
2.3 List of the bacteria both of Gram – negative and Gram positive
with report that APPJ can effect 16
4.1 The summary results of plasma jet in three designs 41
vii
List of Figures
Figures Page
1.1 Types of sterilization / disinfection method 2
2.1 The state of matter 5
2.2 Gas and plasma state: In a plasma, the gas’s electron were
ionized and ripped out from nucleus. The plasm state consists
of charged particles both negative and positive ions 5
2.3 Plasma in nature 7
2.4 Plasma application for surface modification 8
2.5 The approximate of breakdown voltage for several gas
follow the Paschen’s law 10
2.6 The assortment of plasma state (in term of the temperature of electrons
Versus the density of electrons) 11
2.7 Show the effect between the temperatures and pressure on the nature
of the plasma 13
2.8 The schematic of plasma jet 14
2.9 The source of free radicals 15
2.10 Effect of treatment distances on OH radical production 17
2.11 Schematic of atmospheric plasma jet 18
2.12 Show the main structure of skin 23
2.13 Comparative histological aspect of porcine (A) and human (B) skin
(haematoxylin-eosin-saffron staining). HF: hair follicle, Mu and arrowhead:
arrector pili muscle, SwG: Sweat gland, SG: sebaceous gland, Ad:
Adipocytes (hypodermis) 24
2.14 Histologic section of pig skin from the abdomen H&E staining 10X 25
2.15 Contact angles for hydrophobic and hydrophilic surfaces 26
2.16 Different between hydrophobic (right) and hydrophilic (left) 26
3.1 Shown the schematic of plasma jet design 1 27
3.2 Shown the schematic of plasma jet design 2 28
3.3 Shown the schematic of plasma jet design 3 28
3.4 The experiment set up in the laboratory 29
viii
3.5 Function generator MCP SGN1638N model 30
3.6 Power Amplifier 200watt 31
3.7 Ignition coil 32
3.8 Some result of power discharge from MATLAB software calculation 33
3.9 The conical shape of plasma jet on each design 34
4.1 The plasma discharge power obtained from a jet system design 1
is shown as a function of applied frequency at different applied potential 35
4.2 The plasma discharge power obtained from a jet system design 2
is shown as a function of applied frequency at different applied potential 36
4.3 The plasma discharge power obtained from a jet system design 3
is shown as a function of applied frequency at different applied potential 37
4.4 The result of plasma plume length of design 1 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any
flow rate range 2-5 liter/minute 38
4.5 The result of plasma plume length of design 1 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any
flow rate range 2-5 liter/minute 38
4.6 The result of plasma plume length of design 2 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any
flow rate range 2-5 liter/minute 39
4.7 The result of plasma plume length of design 2 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any
flow rate range 2-5 liter/minute 39
4.8 The result of plasma plume length of design 3 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any
flow rate range 2-5 liter/minute 40
4.9 The result of plasma plume length of design 3 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any
flow rate range 2-5 liter/minute 40
4.10 The emission spectra of the plasmas produced with Argon gas,
top figure is shown at the applied potential 2kV. Bottom figure
is shown at the applied potential 3kV 41
1
Chapter 1
Introduction
1.1 Introduction
Plasma technology has played an important role in industrials process
nowadays, especially in semiconductor and electronics industries [1-9]. In fact, plasma
is one of the four fundamental states of matter. It consists of positive and negative
charged particles. There are many types of plasma sources, such as DBD ( Dielectric
Barrier Discharge) [20-22], Plasma jet [22-24], arc and plasma torch, corona discharge
and low-pressure discharge [21, 25]. Atmospheric pressure plasma jet is one of
interesting plasma source because it can be operated in the ambient air, and does not
require a vacuum system. As a result, there is no limitation of the size of chamber [21,
25]. Plasma jet is convenient to handle or use, especially for applying on the specific
area. In addition, atmospheric pressure plasma jet has a characteristics to be able to
induce a high chemical reactivity [26-29].
Nowadays, plasma can be applied on various applications, such as
automotive[30] with mainly used to deposit hard films that provide protection from heat, wear,
and corrosion [31], textile [17, 22], food packaging [22, 32-34], agriculture [35-37],
environmental and biomedical work [17, 36, 38]. When plasma is applied, a surface
will get the bombardment by amount of fast electrons, ions, and free radicals combine
in the UV-Vis spectrum. Lately, the atmospheric pressure plasma jet have showed
successful in present-day biomedical applications by reason of its capability on the
decontamination of biological and sterilization of various surfaces. Sterilization is
represent the process which all of the living microorganisms, including bacterial germs
are killed. Sterilization process can be accomplished by physical term, chemical term
and physiochemical term as show in figure1.
2
Figure 1.1 Types of sterilization / disinfection method [39]
In physical sterilization applications, the popular traditional method is to use
dry or moist heat, such as an autoclave or steam sterilizer. However, these method still
have disadvantages. For example the use of autoclave can cause to a drenching and
wetting on sample, trapped air may reduce the efficacy. Also, it takes long time to cool.
In addition, the steam sterilization process typically takes minutes or hours. Despite of
the fact that heating provides a reliable way to eliminate the living microorganism, it is
not always suitable if it cause to damage heat-sensitive materials, such as electronics,
biological materials, many plastics, and fiber optics [40]. For these reasons chemicals
are also used for sterilization. In these situations, chemicals, both of gases or in liquid
phase, can be used as sterilants. The benefit of the use of gas and liquid chemical
sterilants can avoid the problem of heat damage[40], with the popular chemical are
alcohols, aldehydes, halogens, hydrogen peroxide and ethylene oxide, etc. [39-41].
Although, chemicals sterilization are an effective method. The drawback of
these chemicals were found for example skin irritant, volatile (evaporates rapidly),
inflammable were found in using alcohols. Aldehydes has poor penetration and also
leaves non-volatile residue. Halogen is rapidly inactivated in the presence of organic
matter. Hydrogen peroxide is decomposes in light. Ethylene oxide is highly toxic, also
highly flammable, irritating to eyes, skin, mutagenic and carcinogenic [39]. Plasma
sterilization becomes an alternative technique due to the fact that it can overcome these
problems. There are many researches and studies mention the benefit of using plasma
sterilization, for example a treatment of skin diseases and blood coagulation and wound
healing [43]. With the fact that plasma can produce a mixture of reactive agents, called
3
“reactive oxygen-nitrogen species (RONS)” with the temperature of plasma remaining
close to feed gas temperature, it can result in a safe application to living cells and
tissues. These active plasma species consist of O, O3, NO, NO2 and OH radicals [42,
44-50]. The hydroxyl radical OH plays a key role as an oxidation agent in the
application area [34, 42, 51].
1.2 Statement of problem
There is a growing interest in the use of non-thermal plasmas in biomedicine.
Non-thermal, atmospheric pressure plasma sources are especially suitable for use with
heat-sensitive substrates. Due to having of the bulk temperature of the plasma close to
room temperature which can reduces the adverse effects of thermal loads on materials
such as living tissue. At the cellular level, there are many groups investigating plasma
sterilization in the laboratory. Bacterial spores can be killed after exposure to plasma
due to UV radiation, charged species and reactive neutrals. The reactive species work
to etch the cell until the cell membrane ruptures, and the UV radiation damages the
DNA.
The aim of this research is to develop atmospheric pressure plasma jet for the
use in bio-medical term by comparing the performance of threes designs of plasma jet
models and optimize the condition for generate the atmospheric plasma jet for using in
laboratory. In term to identify the performance of plasma jet, several models of plasma
jet are compared in the operating with the applied voltage at 2-3 kV, 2-7 kHz while
flowrate of argon gas was varied in range of 2-5 liter/minute. The measurement of the
three parameters including with plasma plume, power discharge of plasma and optical
emission spectrum were observed. In addition the effect of plasma on animal skin were
recorded by observation on the property changing, the wettability or water contact
angle.
4
1.3 Scope of study
The 3 models of plasma jet are developed and study the effective by
1.4.1 Study the parameters which will effect on the power discharge and plasma plume
length by vary the frequency, applied voltage and gas flow rate.
1.4.2 Optimize the suitable model for use in the experiment.
1.4.3 Apply to treat on animal skin and observe the differentiation.
1.4 Significance of the study
1.5.1 This research study will develop and improve a model of plasma jet.
1.5.2 A model of plasma jet will use to treat with the other experimental in the future.
1.5.3 The results from this pilot study will be useful in term of study and development
5
Chapter 2
Literatures Review
2.1 Basic and Fundamentals of plasma
Plasma is a fourth state of matters. Normally while the temperature increased,
the matter changes from a solid phase to a liquid phase. Then, it changes to a gas phase.
Finally, the gas is ionized and changes to plasma state [55, 56].
Figure 2.1. The state of matter [57]
Figure 2.2. Gas and plasma state: In a plasma, the gas’s electron were ionized
and ripped out from nucleus. The plasm state consists of charged particles both
negative and positive ions [58]
6
Although the plasma state is nearly the gas state, their differences can be
summarized and described in the table 2.1.
Table 2.1 the differentiation between plasma state and gas state [48]
Plasma has characteristics which are different from other state (solid, liquid and
gas), with the three properties. The first is the debye length which is the length that the
charge was cover (shielding). From the basic principle of plasma, this length must be
much smaller than the distance between the plasmas. Second, the number of particles
in the debye sphere (ND) with a radius equal to the debye length must be a lot of
particles. Third, the periodic movement of plasma can be observed. When the plasma
is disturbed by external action potentials, the electrons, which are much less massive
ions, move out to the balance position and cause the plasma loosed electrical neutrality.
So, they return to the plasma electrically neutral as the original by the restoring force
acting on the electrons to move back to balance point. However, due to inertia, the
electrons will move beyond the balance. The shake around the balance point called
“The frequency of the plasma”. This shake is so quickly that the ions do not have
enough time to response to an electric field with is rapidly changing. Thus, it can
consider that the ions have a fixed position [59].
7
2.1.1 Plasma Criteria
According to a difference characteristics of plasma when compare to other
states. It can be concluded the condition of plasma by following
2.1.1 Debye length ( λD << L)
When L is a length of the plasma dimensions, λD is a range that charged
particles in a plasma were shielded by the opposite charge.
2.1.2 The number of particles ND within a Debye sphere with a radius
λD must be very high ( ND >> 1).
2.1.3 Electricity neutral or nearly neutral conditions (Quasi – neutron).
2.1.4 The frequency of collisions between electrons and neutron
particles is less than the natural frequency of plasma [59].
Irving Langmuir was the first scientist who discovered the plasma in 1928[60]
in his experiment also found the plasma in the natural such as lightning or polar light
in the Arctic and Antarctic, solar wind and earth ionosphere[55, 56]. Moreover, from
natural plasma can be observed in human artifact such as neon lamp.
Figure 2.3 Plasma in nature [61]
When the plasma occurs and touches with the surface as a state of solid
materials such as metallic or plastic, the energy of plasma transfers to the surface of the
8
material. Then, it will cause to properties change such as surface energy.
Many manufacturing industries used this principle for improving surface because
plasma energy will make the change in term of increase more wettability of material's
surface [62].
Figure 2.4 Plasma application for surface modification
Source: http://www.plasmatreat.com
2.2 Generation of plasma
Plasma can created by providing the sufficient energy feed directly to a gas
which purpose to make the rearrange of the specie’s electron structure such as
molecules or atoms. It leads to the creation of electrons or negative charged particles
and ions or positive charged particles. When the system operated and the applied
voltage is sufficient, the electric breakdown of the gas occurs. The air, for example, can
be ionized and leads to the conducting path which a current can flow. This process we
call “discharge”. Normally the inert gases, such as Argon (Ar), helium (He), Xenon
(Xe), and Neon (Ne) are used to serve the working gas for plasma generation. The
discharge can be applied to any situation where a gas is ionized by an electric field. A
current flow the energy will transcribe to the gas electrons. After that, it will transferred
to the species of the neutron by the collisions. Consider follow the probabilistic laws, it
can be divided the collisions into two groups:
Elastic collisions: the neutron specie’s internal energy do not change only give
a little effect slightly higher the kinetic energy.
9
Inelastic collisions: the collision will change the structure of the electronic
inside the neutral species and make the generation of the excited species or
generation of the ions when the high of the electronic energy is sufficient.
For the excited species, most of them have a short lifetime. They emit a photons
when they fallen to the ground state which can be observed by human eyes. When the
plasma spreads throughout to the surrounding air, it will become a gas state by
recombination of the ions and electrons [63, 64].
2.2.1 Ionization processes
The energy that provides to the atoms of different elements in the gaseous phase to
strips out the electrons orbit around the atoms by feeding the energy called “Ionization
Energy”. This Ionization energy depends on the number of electrons of the atoms.
When the gas is ionized, it becomes a conductive media. In order to make the ionization,
the electron energy must exceed the ionization potential of the atom [64].
Ionization is the basic process in plasma because this process serves to
responsible for its creation and existence. This process includes two types of the
ionization. First is the direct ionization which comes from the impact of electrons.
Another one is the ionization which includes non-excited atoms such as radicals or
molecules, related with the interaction of an electrons. This electrons has enough
energetic crash with among of other neutral species with the conditions that all of these
neutral species have a high energy to create an ion – electron pairs.
To generate plasma by applying breakdown potential exceeding voltage of a gas
can be described by Paschen’s law [65], which mentions about the relationship between
the breakdown voltage VB and the gas pressure p and the distance d. In dry air with the
distance between the electrodes at 1 cm, operating at atmospheric pressure requires the
breakdown approximately 30 kV of DC voltage. If the distance d reduces from 1cm to
1 mm, the breakdown voltage reduces to 3.2 kV[65]. In Argon and Helium gases which
have an inert gas properties, it requires about 1.5 kV and 0.75 kV, respectively [63].
10
Figure 2.5 the approximate of breakdown voltage for several gas follow the
Paschen’s law [63, 65]
2.3 Plasma categories
Plasma normally classified into 2 groups. Thermal plasma and Non - Thermal
plasma. According to the relationship between the temperatures of the electrons also
the changing of plasmas properties like electrons density. The table below shown the
main characteristic between Thermal plasma and Non – Thermal plasma [63, 66].
11
Figure 2.6 The assortment of plasma state (in term of the temperature of
electrons versus the density of electrons) [63]
Table 2.2 Represent the major characteristics between Thermal plasma and
Non- thermal plasma [63]
According to the generation of plasma when the energy was given to system, it
can cause an electron movement and then leads to collisions. When inelastic collisions
occur between the electrons and the heavy particles, these can cause the generation of
active species, free radicals in plasma. Elastic collisions, however serve to increase the
heat both of electrons and heavy particles. For this reason in Thermal plasma state, the
electrons temperature (Te), heavy particles temperature (Th) and the gas temperature in
12
the overall (Tg) are in the same range. However, another state of plasma, Non- Thermal
plasma state, the electrons temperature (Te) is different from the previous state because
in this state electrons temperature has much more higher than the heavy particles’s
temperature (Th) [67].
2.3.1 Thermal Equilibrium Plasma or Thermal Plasma
In thermal equilibrium plasmas, radiative processes and collisions will control
the transitions and reactions of the chemical. Collisions phenomena are reversible
process. It means that the excitations process is together with the de-excitation process.
The ionization process is together with the recombination process. In order to come up
at thermal equilibrium state, the local gradients of plasma properties such as density of
electron, thermal conductivity and temperature must low sufficient to make the particle
inside the plasma get up to the equilibrium. Between the heavy particles and the electron
particles inelastic collisions phenomena generated the active species inside plasma
while the heavy particles and electrons were heated up by elastic collisions phenomena.
This is the reason that make the electron’s temperature (Te), heavy particle’s
temperature (Th) and the overall temperature of the gas (Tg) are almost the same [67].
2.3.2 Non Thermal Equilibrium Plasma or Non Thermal plasma
In non-thermal plasma equilibrium state, the heavy particle’s temperature (Th)
is much lower than the electrons temperature (Te) due to the differentiation of mass
between the heavy particles and electrons. The temperature of plasma or the
temperature of the gas (Tg) is dominated by the heavy particle’s temperature i.e. Te>>Th
Tg. The deviation of non-thermal plasma from Boltzman distribution for the electrons’
density could be described by the truth that the electron induced de-excitation rate of
atoms is lower than the corresponding electron induced excitation rate because of
significant radiative de-excitation rate. The moving of electrons is very fast while the
heavy particles seem to static when compare with the electrons. Unlike thermal
equilibrium plasma, the local gradients of plasma properties in non-thermal plasma
state should be high enough and diffusion time should be less than the time. The
particles need to reach the equilibrium. Inelastic collisions between electrons and the
heavy particles are responsible for plasma chemistry, whereas only a few elastic
collisions heat up the heavy particles slightly (Th ≈ 300 - 1000 K). This is the reason
13
why the electrons have highly energetic (Te≈ 10,000- 100,000 K). In non-thermal
plasma the whole plasma temperature remain low (cold plasma) [67].
Atmospheric pressure plasma
The drawback of producing plasma is the limit of low pressure and cost of
maintenance the pump and system. Thus, atmospheric pressure plasma can overcome
this problem. The below figure shows the relationship between the temperature,
pressure and their effects on the nature of the plasma [68]. From the figure it can be
seen if the pressure parameter increases, both electrons and heavy particle temperatures
will change. The entire system of plasma shifts from non-thermal plasma state (cold
plasma) to thermal plasma state. In zone which both of temperature and pressure are
lower (approximately 10-3 to 10-1 Torr), the temperature of electron (Te) is higher than
gas temperature (Tg).
Figure 2.7 Show the effect between the temperatures and pressure on the nature
of the plasma [68]
The plasma in chemistry is mostly related to the inelastic collision phenomena
which occur between the heavy particles and the electrons at the lower conditions of
pressure and temperature. This phenomena cannot increase the plasma’s termperature
or the heavy particle’s temperature. When the pressure increases, it leads to the
reduction of the temperature difference between electron particles and heavy particles.
Both of inelastic collisions process and elastic collisions process serve to increase the
14
heavy particle’s temperature get intensified and plasma reaches close to the
thermodynamic equilibrium. Plasma at atmospheric pressure is almost thermal
equilibrium plasma [63, 68]. The atmospheric pressure plasma can be derived into 2
zones as:
A center of plasma device zone is thermal equilibrium state.
Roundabout of the center zone which is non-thermal equilibrium state. In this
term heavy particle’s temperature is lower than temperature of electrons
particles.
2.4 Atmospheric pressure plasma jet
The structure of plasma jet devices includes two electrodes. It can be found that
there are several design of electrodes either one electrode connect with power; while
another electrode is grounded or is ignored. Some designs look like plasma jet with the
inner and outer tube; while inner tube is used to ignite the plasma and another tube
serves to be a precursor tube [47]. A diagram of an atmospheric-pressure plasma jet is
shown in figure 2.8
Figure 2.8 the schematic of plasma jet
The generation of the discharge normally occurs inside a Pyrex tube. Around
the Pyrex glass tube, a ring shape ground electrode is placed. High purities of Argon
gas is used in our system for the plasma generation.
The plasma form between the two electrodes will spread outside of the Pyrex
glass in form of plasma jet due to the air/gases flowrate which feed to the structure as
15
mention in above from structure as shown in Figure 2.8 The ionized gas from the
plasma jet with operated at ambient air exits through a nozzle.
2.5 Free radicals
Free radicals or reactive species refer as unstable molecules, or atoms due to
its contain of unpaired electrons which can form bonds with other substances. This
process is called “oxidation”. Radicals can have positive, negative or neutral charges.
Normally it comes from external sources such as cigarette smoking, air pollutants,
chemical industrial and x-rays [45, 69].
Figure 2.9 the source of free radicals [70]
When oxidation in the body occurs it will lead to cause the degeneration of the
body. The radicals both of the reactive oxygen species (ROS) and the reactive nitrogen
species (RNS) are well known that they are in great numbers and easily to generate at
the ambient air condition. The lists of example such as hydroxyl radical (OH-),
hydrogen peroxide (H2O2), and nitric oxide (NO-) [44, 71]. Presently, the advantage of
the reaction product from these species are well known that it has strongly oxidative
characteristics that can trigger signaling pathways in living cells. These species has a
key roles in cell growth, metabolism and physiology, immune responses, aging and
several other cell processes [44, 72].
16
Many literatures review that those radicals ROS have a very short of lifetime
and yield the high toxic to the cells in result to damage of other cells and molecules
structures. For examples, oxidation of the lipids and proteins that constitute the
membrane of biological cells causes to the loss of their functions. In such plasma-
induced environments bacterial cells were found to die in minutes or even seconds [45].
In plasma chemistry and plasma medicine the hydroxyl radical (OH-) plays an
important role due to a higher oxidation potential and stronger disinfection power
compared to other oxidative species [73]. These plasma applications have been become
more alternative applied for inactivation both of gram-positive and gram-negative
bacteria the list is shown on the table below.
Table 2.3 List of the bacteria both of Gram – negative and Gram positive with
report that APPJ can effect [46]
Seiji Kanazawa and colleagues studied and measure OH radicals by chemica
luse dosimetry method [74]. They also studied the effect of treatment distances on OH
17
radical production and observed that if the distances increased the amount of OH would
decrease.
Figure 2.10 Effect of treatment distances on OH radical production [74]
2.6 Design of atmospheric plasma jet
In order to treat with living tissue, thermal damage need to be avoid. Plasma jet
can be used to treat without thermal damage or electrical shock because it can generate
a rich, dry chemistry in air at ambient temperature, such as reactive oxygen and nitrogen
species.
There are various type of plasmas in the research fields. Many designs were
reviewed. X Lu and colleagues, for example, studied and reviewed the various designs
of the development of plasma jet [66] and they reported that there are a designs which
can be launch a several centimeter plasma plume, mainly consist of two electrodes and
one dielectric. When the high voltage power supply is turned on and a working gas is
supplied, which usually be Argon and Helium, into the dielectric tube, atmospheric
pressure plasma jet can be generated. The various designs of plasma jet are shown in
the figure 2.11.
18
Figure 2.11 Schematic of atmospheric plasma jet (A) HV electrode not covered
by the dielectric, (B) HV electrode covered by the dielectric tube. (C) The two
ring electrodes are attached to the surface of two centrally perforated dielectric
disks [66]
19
2.7 Current research of atmospheric plasma jet
In plasma state, it consists of high energy particles like ions and electrons which
can transfer energy to molecules or atoms of matter that contact with plasma. It causes
the change of position or change of bond and makes the new creation of rearrange of
atoms. Plasma jets devices are largely used in applications of plasma processing.
Especially, the plasma jet is used for surface treatments: cleaning of surface, surface
etching, surface coating and surface activation. Also Plasma jets have also been used
for medical in term of sterilization or bacterial inactivation. Below is some literatures
that review and mention the application of plasma.
V. Sarron and colleagues studied the plasma plume length characterization by
used the plasma gun which was based on a dielectric barrier discharges. The main
parameters considered were pulse width, applied voltage also the gas flowrate, which
found to have effects to the plasma plume length. The result shown that if the gas
flowrate has increasing the plume will increase until the critical point [24] this result
look similar in thesis work.
K. Shimizu and colleagues set up the experiment using micro plasma, composed
with a two of metallic electrodes, covered with a dielectric barrier under the operated
low discharge voltage of around 1kV to remove the low concentration of formaldehyde
in the ambient air. Formaldehyde (HCHO) is one of the most common VOCs indoors
which come from resins, plastics and building materials such as plywood. HPLC is the
method to measure the concentration of formaldehyde. They found that the removal
efficiency when applied discharge voltage approximate 1 kV is about 50% without
humidity on the other hand if consider the humidity factor the result shown that 60% of
humidity has more efficiency than treat without the humidity [75].
Božena Šerá and colleagues studied and observed the growth of the buckwheat
(Fagopyrum aesculentum) and its germination after exposed with plasma discharge
using air at low- temperature with the reckon time at 180 s, 300 s and 600 s. All of the
samples were six days incubated at 20 °C of temperature with dark conditions. Three
parameters, including the germination rate, the length, and the weight of sprout were
recorded and analyzed with two-way ANOVA method. The result showed that the
plasma technique can be effect to the buckwheat by increase of the germination rate
20
higher than traditional at 9 % after treat with plasma. Also, the length of sprouts was
founded 7% higher with 600s plasma treatment [76].
R. Shrestha and colleagues studied and used the plasma jet in order to inactivation
the prokaryotic cells (Escherichia coli, Staphylococcus aureus) and eukaryotic cells
(Candida albicans, Saccharomyces cerevisae). By using Colony Forming Unit the
results shown that >4 log10 reduction in E. coli and < 2,000 cells reduction in
eukaryotic microalgae C. vulgaris with operated at 27 kHz of frequency, 3.5 kV of
voltage and 2 SLPM argon gas flow rate [77].
Mounir Laroussi and colleagues have been studied the effects of the plasma
pencil which operated at the atmospheric pressure on prokaryotic microorganisms
(bacteria) and cancer cells. They found the positive result that plasma can effect on
bacterias and cancer cells by using counting colony forming unit method also making
the measurement the size of the inactivation zone after2 minutes exposure with the
plasma [46].
Tanaka and colleagues presented a short review describing the interaction of
cancer cells with non-thermal at atmospheric pressure plasma. They outlined recent
innovative studies suggesting that the cold atmospheric plasma can affected on cells
both directly and indirectly. They were no negative effects of plasma on healthy cells,
such as fibroblasts and epithelial cells. This result is appropriate for wound healing
applications [78-80].
A. Hassan and colleagues applied cold plasma on polymers for improve surface
properties of polymers, which is an important requirement for industrial and high
technological applications. In this case, they use Mylar and Makrofol to be a sample
both of samples were cleaned by for 15 minutes then rinsed the samples with distilled
water and make it dry in air for long time before the samples get the interaction by the
RF-plasma source. For the measurement, the static contact angle (SCA) was determined
by using sessile drop method. The droplets of distilled water were inserted on the
sample surface by using a micropipette. They captured an image by using CCD camera
and analyzed by using the Image J software. The result showed that the wettability both
of Mylar and Makrofol decrease [79-81].
Hyun Jung Lee and colleagues studied the effect of atmospheric pressure
plasma jet on the Listeria monocytogenes and processed meat surfaces. The breast and
21
ham were used to study. The He, N2 (both 7 L/min) mixed with 0.07 L/min of O2 were
used to produce the plasma. The exposure time was 2min. The result showed that after
treatment, the number of L. monocytogenes reduced. Inaddition, the reduction of
aerobic bacteria on the meat surface were found [72, 82].
Zifan Wan and colleagues were study the inactivation of Salmonella and its
effect on the egg quality by using an atmospheric pressure plasma jet. A medium A
grade eggs were purchased from local store whereas the Salmonella enterica serovar
Enteritidis (strain 190:88) was obtained from Department of Food and science. 0.1 ml
SE inoculum was spot inoculate on the sideway of eggs. Then, the eggs were allowed
to air dry for 1 hour in a laminar flow cabinet at room temperature to allow attachment
of bacterial cells. After drying, the eggs were placed in a refrigerator at 5 ̊C for
overnight to reach treatment temperature prior to the plasma treatment. The eggs were
treated with high voltage about 85 kV. A reduction of 5.3 log cfu/egg was observed
[83].
N.N. Misra and colleagues. Applied cold plasma on strawberries, which
purchased from the local store fruit market and treated by atmospheric cold plasma.
The plasma were generated with a 60 kV dielectric barrier discharge (DBD) pulsed at
50 Hz, across a 40 mm electrode gap, generated inside a sealed package containing
ambient air (42% relative humidity). The result showed the background microflora
(aerobic mesophillic bacteria, yeast and mould) of strawberries treated for 5 min was
reduced by 2 log10 within 24 hours [32].
A.-Young Moon et al. (2016) studied and developed atmospheric pressure
plasma source to remove the microorganisms on fruit product. In this case, the grapes
were trialed. By using flow of plasma gas with avoiding direct contact between plasma
and grapes. The observation was recorded and found that the fungi colony density of
the non-treated case consistently increased from 2.07 to 4.24 Log CFU/g. While the
fungi colony density of the plasma treated air case rapidly decreased from 2.07 to 0.7
Log CFU/g for 12 hours and then gradually increased. This indicates that atmospheric-
pressure air plasmas can hamper the growth of fungi and improve storage quality
through initial decontamination [33].
22
Alison Lacombe and colleagues used atmospheric pressure plasma to kill the
microorganism on blueberries. Blueberries were obtained from the local grocery store
and held at 4° C until use to treat with plasma treatment. 5 blueberries were treated
under plasma working distance of 7.5 cm for 0, 15, 30, 45, 60, 90, or 120s. All
treatments with atmospheric pressure plasma significantly (P < 0.05) reduced after
exposure, with reductions ranging from 0.8 to 1.6 log CFU/g and 1.5 to 2.0 log CFU/g
compared to the control after 1 and 7 days, respectively [34].
Walsh and Kong reported on the frequency effects of plasma bullets. They
performed experiments from 10 to 500 kHz and found three different types of plasma
dynamics. When the frequency increased from 80 kHz to 170 kHz, the plasma appeared
much longer and brighter. They attributed this to the increased current density at higher
frequencies [84].
2.8 Brief information on the animal skin
2.8.1 Information about Skin
The largest organ of our body is the skin contains of a complex structure’s layer,
which forms and serve to a barrier play an important role such as protection our body
from environmental aggressions (biologic, physical or chemical), thermoregulation,
metabolism and sensation. Normally our skin was divided into 3 layers, the outermost
layer or epidermis, the middle layer or dermis and the inmost layer or hypodermis or
subcutaneous. The epidermis layer, consists of a specific constellation of cells known
as keratinocytes, which function to synthesize a long keratin with a protective role. The
middle layer is the dermis layer, basically made up of the fibrillar structural protein
which we known as collagen. The dermis layer is on top of the subcutaneous tissue, or
panniculus, which contains small lobes of fat cells known as lipocytes. The thickness
of these layers varies considerably, depending on the geographic location on the
anatomy of the body.
The epidermis usually is divided into four layers according to keratinocyte
morphology and position as they differentiate into horny cells, including the basal cell
layer (stratum germinativum), the squamous cell layer (stratum spinosum), the granular
cell layer (stratum granulosum), and the cornified or horny cell layer (stratum
corneum). The dermis is an integrated system of fibrous, filamentous, and amorphous
23
connective tissue that accommodates stimulus-induced entry by nerve and vascular
networks, epidermally derived appendages, fibroblasts, macrophages, and mast cells.
Other blood-borne cells, including lymphocytes, plasma cells, and other leukocytes,
enter the dermis in response to various stimuli as well. The last one subcutaneous layer,
this layer functions as a storehouse of energy [85] [86].
Figure 2.12 Show the main structure of skin
2.8.1.1 Porcine skin
Due to the size of swine is comparable to humans, and both species share many
similarities in their cardiovascular and immune systems [87]. As in humans skin,
porcine skin is also divided into three layers, the epidermis, the dermis and the
hypodermis (or subcutaneous) [88].
Pork’s skin is similar to human’s skin in term of epidermal thickness and
dermal–epidermal thickness ratios, a basement membrane zone forming the interface
between the epidermis and the dermis. It constitutes a support to epidermal cells that
plays a crucial role in the polarity of growth and cytoskeleton organization of basal
epidermal. Pork’s skin are almost hairless and has a fixed subcutaneous layer and
dermal hair follicles like humans skin and look like to be thicker on the dorsum of the
neck than in humans and also less vascular in all areas. Porcine skin consist of clearly
basophilic granules along the basal layer. There are few eccrine sweat glands, and this
24
among of eccrine glands make the different between porcine skin and human skin.
Porcine skin have apocrine sweat glands and sebaceous glands throughout the skin [77].
Figure 2.13 Comparative histological aspect of porcine (A) and human (B) skin
(haematoxylin-eosin-saffron staining). HF: hair follicle, Mu and arrowhead: arrector
pili muscle, SwG: Sweat gland, SG: sebaceous gland, Ad: Adipocytes (hypodermis) [82]
2.8.1.2 Structure of porcine skin
Porcine skin can be shown on Figure 2.13 Porcine skin have pH about 6-7 while
humans skin have pH approximately 5. The epidermis layer was described as 70-140
µm and composed of the following layers from outside to inside: stratum corneum,
stratum lucidum, statum granulosum, stratum spinosum and stratum basale. The
epidermis ends at the epidermal-dermal junction. The cellular turnover rate in the skin
is approximately 28-30 days, which is similar to humans [89].
25
Figure 2.13 Histologic section of pig skin from the abdomen.
H&E staining 10X
Reference: M. Michael Swindle, 2008 [90]
2.8.1.3 Structure of the cell membrane
The plasma membrane allows nutrients and waste to travel to and from the cell,
while maintaining the structural integrity of the cell and sensing changes in the external
environment. It is made up of a lipid bilayer and proteins, each accounting for about
50% of the weight of the membrane. The lipids form the basic structure, while the
proteins distributed throughout the membrane are responsible for cell communication,
recognition and adhesion. The lipid bilayer is arranged with the hydrophilic heads
facing out, and the hydrophobic tails forming the interior of the wall [51].
2.9 Wettability
Characteristic of wet or liquid adhesion to the surface of solids is one of
important properties for skin study. The wettability of surfaces involves the two forces.
1. Cohesive force: the bond between the same substances. In this case, it is an
attempt to force the molecules of liquid form into each cluster.
2. Adhesive force: the bond between different substances. It refers to molecular
forces between liquid and solid. This is the force that opposites to the cohesive
force. Adhesion tries to make the trickle of liquid separate from each other.
Consider as the water settles on the surface of the solid state cause balance the
adhesion strength and cohesive strength. If the adhesion force is greater than an
extremely cohesive force, water distribution is attached on the surface of the solid. On
26
the other hand, if the adhesion force is less than the cohesive force connection. Water
is not adhesion, but it falls out of the surface. Then, it combines into drops and roll back
and forth on the surface of solids, like a drop of water on a lotus leaf [91].
In consideration of the wetting liquid on the surface of solids, the balance of the
two forces leads to another significant quantity. Commonly used measure of wet which
called contact angle is the angle between a drops of liquid and the surface. The contact
angle between 0 – 90 degree can define as a good wetting or “Hydrophilic”. Whereas
contact angle between upper from 90 degree can define as “Hydrophobic”[92]. This
information can be used to define the wet of water on the surface.
Figure 2.14 Contact angles for hydrophobic and hydrophilic surfaces [92]
Figure 2.15 Different between hydrophobic (right) and hydrophilic (left) [92]
27
Chapter 3
DEVELOPMENT OF ATMOSPHERIC PLASMA JET
3.1 Three designs of plasma jet and power supply system
In this thesis, it starts from deign a three designs of plasma jet with have slightly
difference and optimize each design. Plasma jet is usually consist of two electrodes (at
least one of them covered with a dielectric material). In figure 3.1-3.3, it shows for each
design considered. The first design has a tip shape at the exist end, shown in figure 3.1.
In figure 3.2, it shows the schematic of design 2. In figure 3.3, the design 3 uses the
glass same size with design 2 and add another part that is the capillary tube to cover an
inner electrode.
Figure 3.1 shown the schematic of plasma jet design 1(The end of the tube has a
nip shape)
28
Figure 3.2 shown the schematic of plasma jet design 2
Figure 3.3 shown the schematic of plasma jet design 3 (Dielectric covered an
inner electrode)
In this work, copper ring was used as an outer electrode while the stainless steel was
used as an inner electrode. The conditions used to investigate and recorded performance
of three designs of atmospheric pressure plasma jet are varying the three parameters
voltage, flowrate and frequency. The range of voltage used was 2-3 kV, while the range
of argon gas flowrate was 2-5 liter/minute and the frequency was 2-7 kHz. For each
designs with three times repetition per day. This experimental were conducted for 5
days.
29
3.2 Structure of atmospheric plasma source APPJ
Figure 3.4 the experiment set up in the laboratory
Lists of component of atmospheric pressure plasma jet
3.1.1 AC power supply which can generate the high voltage in range 1- 40 kV,
Frequency in range 50 – 100 kHz
3.1.2 Plasma device
3.1.2 High voltage probe Peak tech 1:
3.1.4 Oscilloscope Rigol DS1052E 50MHz 1GSa/S model.
3.1.5 Camera Nikon D5100 model
3.1.6 Optical Emission Spectrum Device
Power supply system
The power supply starts with a function generator to send a sine signal to the
amplifier. The amplifier receives the signals and then amplifies the input signal and
sends the signal in from of output signal to the ignition coil car, which serves to increase
the voltage to rise to apply on electrodes of plasma jet system.
30
Function Generator
A waveform signal generator can produce several types of waves, sine waves,
square waves. Triangle wave, etc., can be the source of signal frequency between about
1 Hz to 10 MHz for trial use the signal generator MCP model SG1638N was used in
the experiment, as shown in figure 3.5.
Figure 3.5 Function generator MCP SGN1638N model
Amplifier
An amplifier is used to increase the amplitude of the input signal from the
function generator and prepare to be forwarded to the output signal sent to the ignition
coil car. The main purpose of the amplifier is to amplify the signal to a more size. And
the signal must be minimum distortion [93]. MOSFET MKII 2 0 0 W model was used
in the experiment.
31
Figure 3.6 Power amplifier Power MOSFET MKII 200 W model
Ignition coil
An ignition coil is used for an extension of voltage to reach up high voltage.
Inside the ignition coils, it is composed of primary coil, wrapped around a steel core
with a large copper wire by 150 to 300 turns cover the secondary coil, which is a small
copper wire wrapped around an iron core approximately 2000 turns. In order to protect
short circuit between these coils, the thin paper was placed in the middle. Also it
contains the oil inside for make the cooling. One end of the primary coil is connected
to the positive (+) and the other end is connected to the negative (-) of the ignition coil.
For the secondary coil, it is connected at one end to a positive (+) of the ignition coil
and the other end is connected to the high voltage power pole in the middle of ignition
coils for high-voltage lines on the cap. The ignition coil HANSHIN E301 model was
used in the experiment.
32
Figure 3.7 Schematic of ignition coil
Source from http://www.motorera.com/dictionary/co.htm
3.3 Parameters to identify the performance of plasma jet
3.3.1 Measurement of power discharge
The power consumption is significant for all plasma applications[33]. A. Janeco
and colleagues studied and gave the information that “A common method for measuring
the power consumption is by calculating the area of a Lissajous figure which obtained
from the applied voltage and integrated charge through a capacitor and computing the
area of the figure.” [94, 95].
The oscilloscope displays and records an electric signal such as the applied
voltage feed into plasma jet system or the voltage signal which across the capacitor.
This is used to analyze the power discharge. To measure the power discharge, in the
experiment the oscilloscope was used to measure the high voltage (Vmax) and Vc or
voltage across the capacitor and use Q = CVc to calculate the charge result. Follow the
below equations;
Equation (1)
P = W
t When P = power discharge (Watt)
W = work (J)
t = time (s)
33
Equation (2)
2
T t
2T t
0
0
dt i(t)v(t) W
When Q = CV Vc= Voltage across C
Equation (3)
dt
dVC
dt
dQ i(t)
c,
Equation (4)
2
T t
2T - t
2T t
2T - t
c
0
0
0
0
dQ(t) v(t) dVC v(t) W
From the oscilloscope, the Lissajouses graph between applied voltage and
charge on capacitor can be obtained. The numerical technique in MATLAB is used to
estimate the plasma discharge power.
Figure 3.8 some result of discharge power from MATLAB software calculation
34
3.3.2 Measurement of plasma plume length
In experiment, the camera was used for recorder the plasma plume length. It is
found that the plasma output when it lunches out to the ambient air. It has a conical
shape with purple colour, depending on type of working gas. The below figure shown
the shape of plasma output in each design with Air and Argon as working gas. The left
hand side are the output plasma the first design, the second design, and the third design
respectively.
Figure 3.9 the conical shape of plasma jet on each design
3.3.3 Optical Emission spectroscopy characteristic
In nature, plasma is considered as a quasi-neutral charge. It consists of the
mixture of highly active species which plays an important role on the substrate
treatment. In order to confirm the existent of these active species, the optical emission
spectroscopy (OES) is used. OES is well known as non-disturbing and non-invasive
technique for plasma diagnostics. In plasmas, excitation and de-excitation processes
keep going on. When molecules reach de-excite state, they emit radiations, which the
OES can capture these emission radiations of active species. The intensity of emission
radiation is measured as the function of the wavelength. As all of the transitions taken
placed at very specific wavelengths, these spectrum can be used to identify different
active species[67].
35
Chapter 4
RESULTS AND DISCUSSION
4.1 Discharge power of plasma jet
The relation between the plasma power and voltage also the frequency of each
designs for different flow-rate is shown in figure 4.1 - 4.3.
It can be seen that as either the voltage or frequency increases, the power
discharge increases. However, it seems to be more sensitive an increase of the supplied
voltage. This result agrees with the report by Attri, P and colleagues [96]. However the
flow rate, seems to have no impacts on the discharge power of atmospheric plasma.
4.1.1 Discharge power of design 1
In order to obtain the discharge power, the equation (4) in the previous chapter
was used to calculate by using MATLAB software. The result for each design are
showed as in figure 4.1 – 4.3.
Figure 4.1 The plasma discharge power obtained from a jet system design 1 is
shown as a function of applied frequency at different applied potential
0
500
1000
1500
0 1 2 3 4 5 6 7 8
Dis
char
ge P
ow
er
(mw
)
Frequency (kHz)
2lpm-2kV 3lpm-2kV4lpm- 2kV 5lpm- 2kV2lpm- 3kV 3lpm - 3kV4lpm - 3kV 5lpm - 3kV
36
4.1.2 Discharge power of design 2
Figure 4.2 The plasma discharge power obtained from a jet system design 2 is
shown as a function of applied frequency at different applied potential
0
500
1000
1500
0 1 2 3 4 5 6 7 8
Dis
char
ge p
ow
er (
mw
)
frequency (kHz)
2lpm - 2kV 3lpm -2kV
4lpm -2kV 5lpm -2kV
2lpm -3kV 3lpm -3kV
4lpm -3kV 5lpm - 3kV
37
4.1.3 Power discharge of design 3
Figure 4.3 The plasma discharge power obtained from a jet system design 3 is
shown as a function of applied frequency at different applied potential
4.2 Plasma plume length of plasma jet
The plasma plume length was observed by using camera and the result showed
that the plasma plume length will increase if the apply voltage increase. In this work
The second design yields the highest length with 1.8 cm when compare with the other
designs
The correlation method was used to analyze and found that it has a relation for
each other with agreeable to the literature reviews that the increasing of high voltage,
frequency and gas flow should be increase of the plasma plume[97]. The similarity
reviews mentioned that the plasma plume length will increase until it reach up the
critical value [24].
0
500
1000
1500
0 1 2 3 4 5 6 7 8
Dis
char
ge p
ow
er
(mw
)
Frequency (kHz)
2lpm -2kV 3lpm -2kV4lpm -2kV 5lpm - 2 kV2lpm -3kV 3lpm -3kV4lpm -3kV 5lpm -3kV
38
4.2.1 Plasma plume length of design 1
Figure 4.4 The result of plasma plume length of design 1 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any flow
rate range 2-5 liter/minute
0
0.5
1
1.5
2
0 2 4 6 8
Pla
sma
plu
me
len
gth
(cm
)
Frequency (kHz)
2lpm-2kV 3lpm-2kV
4lpm- 2kV 5lpm- 2kV
39
Figure 4.5 The result of plasma plume length of design 1 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any flow
rate range 2-5 liter/minute
The result shown that both of frequency and flowrate do not effect on the plasma
plume length. For this design 1 at condition 2kV, 2- 7 kHz and 2-5 liter/minute the
maximum plasma plume length approximately 0.4 cm. When operate at the condition
3kV, 2- 7 kHz and 2-5 liter/minute shown the same trend lined that frequency and
flowrate do not effect on the plasma plume length for this result after increase the
applied potential from 2kV to 3kV the maximum plasma plume is approximately 1.0
cm.
0
0.5
1
1.5
2
0 2 4 6 8
Pla
sma
plu
me
len
gth
(cm
)
Frequency (kHz)
2lpm- 3kV 3lpm- 3kV
4lpm- 3kV 5lpm - 3kV
40
4.2.2 Plasma plume length of design 2
Figure 4.6 The result of plasma plume length of design 2 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any flow
rate range 2-5 liter/minute
Figure 4.7 The result of plasma plume length of design 2 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any flow
rate range 2-5 liter/minute
0
0.5
1
1.5
2
2.5
3
0 1 2 3 4 5 6 7 8
Pla
sma
plu
me
len
gth
(cm
)
frequency (kHz)
3lpm -2kV 4lpm -2kV
5lpm -2kV 2lpm - 2kV
0
0.5
1
1.5
2
2.5
3
0 2 4 6 8
Pla
sma
plu
me
len
gth
(cm
)
frequency (kHz)
2lpm -3kV
3lpm -3kV
4lpm -3kV
5lpm - 3kV
41
The result from design 2 also give the same notice with the previous design that
the flow rate and frequency do not effect on plasma plume length. And for this design
2 when operated at 2kV, 2- 7 kHz and 2-5 liter/minute Argon gas flow rate is
approximately 0.8 cm. When operate at the condition 3kV, 2- 7 kHz and 2-5 liter/minute
shown the same trend lined that frequency and flowrate do not effect on the plasma
plume length for this result after increase the applied potential from 2kV to 3kV the
maximum plasma plume is approximately 1.7 cm.
4.2.3 Plasma plume length of design 3
Figure 4.8 The result of plasma plume length of design 3 shown as a function of
applied frequency whereas the applied potential was fixed at 2kV at any flow
rate range 2-5 liter/minute
0
0.5
1
1.5
2
0 1 2 3 4 5 6 7 8
Pla
sma
plu
me
len
gth
(cm
)
Frequency (kHz)
2lpm -2kV 3lpm -2kV
4lpm -2kV 5lpm - 2 kV
42
Figure 4.9 The result of plasma plume length of design 3 shown as a function of
applied frequency whereas the applied potential was fixed at 3kV at any flow
rate range 2-5 liter/minute
The result from design 3 also give the same notice with the two previous designs
that the flow rate and frequency do not effect on plasma plume length. It ‘s founded tht
only the applied voltage is When operate at the condition 3kV, 2- 7 kHz and 2-5
liter/minute shown the same trend lined that frequency and flowrate do not effect on
the plasma plume length for this result after increase the applied potential from 2kV to
3kV the maximum plasma plume is approximately 1.7 cm.
0
0.5
1
1.5
2
0 1 2 3 4 5 6 7 8
Pla
sma
plu
me
len
gth
(cm
)
Frequency (kHz)
2lpm -3kV 3lpm -3kV
4lpm -3kV 5lpm -3kV
43
Table 4.1 The summary results of plasma jet in three designs
The plasma performance based on three designs of atmospheric plasma jet
system are investigated. It was found that after varying the three parameters voltage,
flow rate and frequency. The first design yields the highest power discharge among
those designs considered. When the supplied voltage, the frequency, and Argon flow-
rate, the similar trend has been observed from those three designs. For the plasma plume
length term, Design 2 yields the highest plume length due design 2 has more diameter
at the end of the pyrex glass tube when compare with design 1 which has a narrow
shape at the end of the pyrex glass tube. When the working gases in this system, Ar and
Air feed into the design 1. The working gases will accumulate nearly the end at the tube
and when the plasma launch out it will rapid mixing to the ambient air. Thus, the plasma
plume length sound to shorter than the atmospheric plasma design 2.
4.3 Optical Emission Spectroscopy of plasma jet
Power discharge
Design 1 Design 2 Design 3
1405 ± 156 mW 989 ± 416 mW 484 ± 69 mW
Plasma plume
length
1.0 ± 0 cm 1.8 ± 1 cm 0.3 ± 0 cm
44
Figure 4.10 The emission spectra of the plasmas produced with Argon gas, top
figure is shown at the applied potential 2kV. Bottom figure is shown at the
applied potential 3kV
For the emission spectra obtained from plasmas jet with Argon gas (Ar) flow.
Emissions from the OH radical which formed from the water vapor in ambient air
(around 306,307,308,309,310) are present in the emission spectra [23, 74, 98-100].
Some N2 line emissions also present in the spectra. The emission spectra of Argon is
appear at the right end of spectra [23]. The results of OES spectrum represent the similar
trend lines in these 3 designs of plasma jet. The trend lines seem that Argon flow rate
2 liter/minute give the highest count when compare with the others. This result seem
agreeable with Boonyawan. D et al. (2016)[23]. With mention that The OH radical
emission light is quite intense at argon gas flow rate between 2 liter/minute to
3 liter/minute.
4.4 Impact of plasma jet on pork skin
The effect on pork skin was observed after 30 seconds and 60 seconds exposing
with atmospheric pressure argon plasma jet. The measurement was carried out using
the Image J software. The result of pork skins after treated with plasma for 30 seconds
and 60 seconds are show in below figure.
45
Figure 4.11 Contact angle on pork skin. Without treated with plasma jet the
degree has higher than treated with plasma jet
After treating with atmospheric plasma on pork skin, the result shows that
contact angle decreases. It implies that atmospheric pressure plasma may not be
good for healing wound if it considers only this factor of wettability because the
wound will hard to dry. However, if only sterilization is considered, plasma jet
might be able to use for killing microorganisms due to the contact angle decrease.
44
Chapter 5
Conclusions and Recommendations
5.1 Conclusions
In this work, it is founded that the power discharge depend on applied voltage
and frequency and it is does not depend on the Argon flow rate. For the plasma plume
length, the results show that there are no effect on plume although the applied voltage,
frequency and the flow rate were varied when analyzed by ANOVA method. The
further study is try to analyzed the effect on plasma plume by used Correlation method
and it was found that they have a relation between the applied voltage and the frequency
come up with the flow rate. Moreover, the observation of the OES spectrum was
recorded and the trend line for each design is look similar. When consider the effect of
three parameters, it is founded that the trend line will increase if the applied voltage and
the frequency increase. For the term of the flow rate variation, it is founded that the
flow rate at 2lpm give the most count when compare to another flow rates. Thus, the
suitable design in the laboratory should be the first design with the condition 3kV 7
kHz and 2 liter/minute. For the effect of plasma on pork skin, it is observed in term of
the wettability or water contact angle. The result shows that the contact angle decreases
after the explosion with plasma or the pork’s skin increases its hydrophilic property.
5.2 Recommendation
It is recommended that a dielectric of the plasma jet should be replaced the
quartz glass instead of Pyrex glass because the quartz has more heat resistance.
Currently the Pyrex always crack when it exposes with the high applied voltage. For
this case the plasma jet system will available to operate at the high voltage more than
the traditional system.
45
References
1. Lu, H.H., et al., Improved interfacial quality of GaAs metal-oxide-
semiconductor device with NH3-plasma treated yittrium-oxynitride as
interfacial passivation layer. Microelectronics Reliability, 2016. 56: p. 17-21.
2. Kao, C.H., et al., Fabrication of multianalyte CeO2 nanograin electrolyte–
insulator–semiconductor biosensors by using CF4 plasma treatment. Sensing
and Bio-Sensing Research, 2015. 5: p. 71-77.
3. Cho, S.J., et al., A study of the impact of in-situ argon plasma treatment before
atomic layer deposition of Al2O3 on GaN based metal oxide semiconductor
capacitor. Microelectronic Engineering, 2015. 147: p. 277-280.
4. Oh, I.-K., et al., Very high frequency plasma reactant for atomic layer
deposition. Applied Surface Science, 2016. 387: p. 109-117.
5. Ha, D., et al., Improvement of principal component analysis modeling for
plasma etch processes through discrete wavelet transform and automatic
variable selection. Computers & Chemical Engineering, 2016. 94: p. 362-369.
6. Altmannshofer, S., I. Eisele, and A. Gschwandtner, Hydrogen microwave
plasma treatment of Si and SiO2. Surface and Coatings Technology, 2016.
304: p. 359-363.
7. Zeba, I., et al., Electron–hole two-stream instability in a quantum
semiconductor plasma with exchange-correlation effects. Physics Letters A,
2012. 376(34): p. 2309-2313.
8. Sun, D.L., et al., Preparation of carbon nanomaterials using two-group arc
discharge plasma. Chemical Engineering Journal, 2016. 303: p. 217-230.
9. Yepez, X.V. and K.M. Keener, High-voltage Atmospheric Cold Plasma
(HVACP) hydrogenation of soybean oil without trans-fatty acids. Innovative
Food Science & Emerging Technologies, 2016. 38, Part A: p. 169-174.
10. Akitsu, T., et al., Plasma sterilization using glow discharge at atmospheric
pressure. Surface and Coatings Technology, 2005. 193(1–3): p. 29-34.
11. Rossi, F. and O. Kylián, 6 - Sterilization and decontamination of surfaces by
plasma discharges, in Sterilisation of Biomaterials and Medical Devices.
2012, Woodhead Publishing. p. 117-150.
12. Mrad, O., S. Saloum, and A. Al-Mariri, Effect of a new low pressure SF6
plasma sterilization system on polymeric devices. Vacuum, 2013. 88: p. 11-16.
13. Yang, L., J. Chen, and J. Gao, Low temperature argon plasma sterilization
effect on Pseudomonas aeruginosa and its mechanisms. Journal of
Electrostatics, 2009. 67(4): p. 646-651.
14. Dasan, B.G., I.H. Boyaci, and M. Mutlu, Nonthermal plasma treatment of
Aspergillus spp. spores on hazelnuts in an atmospheric pressure fluidized bed
plasma system: Impact of process parameters and surveillance of the residual
viability of spores. Journal of Food Engineering.
15. Lee, K.-Y., et al., Sterilization of Escherichia coli and MRSA using
microwave-induced argon plasma at atmospheric pressure. Surface and
Coatings Technology, 2005. 193(1–3): p. 35-38.
16. Ekem, N., et al., Sterilization of Staphylococcus aureus by atmospheric
pressure pulsed plasma. Surface and Coatings Technology, 2006. 201(3–4): p.
993-997.
46
17. Park, D.J., et al., Sterilization of microorganisms in silk fabrics by microwave-
induced argon plasma treatment at atmospheric pressure. Surface and
Coatings Technology, 2008. 202(22–23): p. 5773-5778.
18. Chang, Y.-T. and G. Chen, Oral bacterial inactivation using a novel low-
temperature atmospheric-pressure plasma device. Journal of Dental Sciences,
2016. 11(1): p. 65-71.
19. Hung, Y.-W., et al., Effect of a nonthermal-atmospheric pressure plasma jet
on wound healing: An animal study. Journal of the Chinese Medical
Association, 2016. 79(6): p. 320-328.
20. Kozato, Y., et al., Flow control of a rectangular jet by DBD plasma actuators.
International Journal of Heat and Fluid Flow.
21. Claire Tendero a, Christelle Tixier a, Pascal Tristant a, Jean Desmaison a,
Philippe Leprince b, Atmospheric pressure plasmas: A review. Spectrochimica
Acta Part B, 2006. 61: p. 2-30.
22. al, S.S.e. APPLICATION OF PLASMA IN DIFFERENT BRANCHES OF
INDUSTRIES. in RMUTP International Conference: Textiles & Fashion 2012.
2012. Thailand.
23. Thana, Y., A. Ngamjarurojana, and D. Boonyawan, Analysis of cold
atmospheric-pressure bio-medicine plasmas by using UV absorption
spectroscopy. Surface and Coatings Technology, 2016. 306, Part A: p. 106-
112.
24. V. Sarron, E.R.e.a., Plasma plume length characterization. International
Plasma Chemistry Society.
25. Andreas Schutze, J.Y.J., Steven E. Babayan, Jaeyoung Park, Gary S. Selwyn,
and Robert F. Hicks, The Atmospheric-Pressure Plasma Jet: A Review
and Comparison to Other Plasma Sources. IEEE TRANSACTIONS ON
PLASMA SCIENCE, 1998. 26.
26. Brun, P., et al., Disinfection of Ocular Cells and Tissues by Atmospheric-
Pressure Cold Plasma. PLoS ONE, 2012. 7(3): p. e33245.
27. Juliana Aparecida Delben et al, Effect of Atmospheric-Pressure Cold Plasma
on Pathogenic Oral Biofilms and In Vitro
Reconstituted Oral Epithelium. PLOS ONE 2016.
28. Delben, J.A., et al., Effect of Atmospheric-Pressure Cold Plasma on
Pathogenic Oral Biofilms and In Vitro Reconstituted Oral Epithelium. PLoS
ONE, 2016. 11(5): p. e0155427.
29. Zhen-Zhou SU et al, OH RADICAL GENERATION BY ATMOSPHERIC
PRESSURE PLASMA AND ITS QUANTITATIVE
ANALYSIS BY MONITORING CO OXIDATION Fuel Chemistry Division
Preprints, 2002. 47((1)): p. 324.
30. Plasma, H. Plasma Treatment in the Automotive Industry. [cited 2016 17];
Available from: https://plasmatreatment.co.uk/industries/plasma-treatment-
automotive/.
31. Moravej, M., Chemistry and Physics of Atmospheric Pressure Argon Plasmas,
in Chemical Engineering. 2005, UNIVERSITY OF CALIFORNIA.
32. Misra, N.N., et al., In-package atmospheric pressure cold plasma treatment of
strawberries. Journal of Food Engineering, 2014. 125: p. 131-138.
47
33. Moon, A.Y., et al., Feasibility study of atmospheric-pressure plasma treated
air gas package for grape's shelf-life improvement. Current Applied Physics,
2016. 16(4): p. 440-445.
34. Lacombe, A., et al., Atmospheric cold plasma inactivation of aerobic
microorganisms on blueberries and effects on quality attributes. Food
Microbiology, 2015. 46: p. 479-484.
35. Butscher, D., et al., Inactivation of microorganisms on granular materials:
Reduction of Bacillus amyloliquefaciens endospores on wheat grains in a low
pressure plasma circulating fluidized bed reactor. Journal of Food
Engineering, 2015. 159: p. 48-56.
36. Thirumdas, R., et al., Influence of low pressure cold plasma on cooking and
textural properties of brown rice. Innovative Food Science & Emerging
Technologies, 2016. 37, Part A: p. 53-60.
37. Kádár, Z., et al., Enhanced ethanol production by removal of cutin and
epicuticular waxes of wheat straw by plasma assisted pretreatment. Biomass
and Bioenergy, 2015. 81: p. 26-30.
38. Schneider, J., et al., Investigation of the practicability of low-pressure
microwave plasmas in the sterilisation of food packaging materials at
industrial level. Surface and Coatings Technology, 2005. 200(1–4): p. 962-
966.
39. Disinfection, S.a. Sterilization and Disinfection. 2008.
40. Sterilization (microbiology). 2016 24 October 2016; Available from:
https://en.wikipedia.org/wiki/Sterilization_(microbiology).
41. BioLabs, P. STERILIZATION VALIDATIONS: Chemical Sterilization. 2015;
Available from: http://www.pacificbiolabs.com/ster_chemical.asp.
42. Shintani, H., et al., Gas plasma sterilization of microorganisms and
mechanisms of action. Experimental and Therapeutic Medicine, 2010. 1(5): p.
731-738.
43. Kuo, S.P., Air plasma for medical applications. J. Biomedical Science and
Engineering, 2012: p. 481-495.
44. Pankaj Attri1, Y.H.K., Dae Hoon Park1, Ji Hoon Park1, Young J. Hong1, Han
Sup Uhm1, and A.F.E.H.C. Kyoung-Nam Kim2, Generation mechanism of
hydroxyl radical species and its lifetime prediction during the plasma-initiated
ultraviolet (UV) photolysis. SCIENTIFIC REPORTS, 2015.
45. Y.J. Hong, C.J.N., K.B. Song, G.S. Cho, H.S. Uhm, D.I. Choi and E.H. Choi2,
Measurement of hydroxyl radical density generated from the atmospheric
pressure bioplasma jet. 15th INTERNATIONAL CONFERENCE ON
LASER AIDED PLASMA DIAGNOSTICS, OCTOBER 13–19, 2011 JEJU,
KOREA, 2012.
46. Laroussi, M., Low-Temperature Plasma Jet for Biomedical Applications: A
Review. IEEE TRANSACTIONS ON PLASMA SCIENCE, , 2015. 43.
47. Thiébaut, J.M., et al., Comparison of surface cleaning by two atmospheric
pressure discharges. Surface and Coatings Technology, 2003. 169–170: p.
186-189.
48. Yaffa Eliezer, S.E., The Fourth State of Matter: An Introduction to the Physics
of Plasma. 1989.
48
49. Mohd Nasir, N., et al., Cold plasma inactivation of chronic wound bacteria.
Archives of Biochemistry and Biophysics, 2016. 605: p. 76-85.
50. Setsuhara, Y., Low-temperature atmospheric-pressure plasma sources for
plasma medicine. Archives of Biochemistry and Biophysics, 2016. 605: p. 3-
10.
51. Yonson, S., Cell treatment and surface functionalization using the
atmospheric pressure glow discharge plasma torch (APGD-0, in Chemical
Engineering. 2006, McGill University,.
52. Paola Brun et al, Disinfection of Ocular Cells and Tissues by
AtmosphericPressure Cold Plasma. www.plosone.org, 2012. 7(3).
53. Andrei Vasile Nastuta et al, Atmospheric pressure plasma jet—Living tissue
interface: Electrical, optical, and spectral characterization. JOURNAL OF
APPLIED PHYSICS, 2013.
54. Song, J., et al., Role of ambient dielectric in propagation of Ar atmospheric
pressure nonequilibrium plasma jets. Physics of Plasmas, 2015. 22(5): p.
050703.
55. What is Plasma?, in The Fourth State of Matter. 2001, Taylor & Francis.
56. A Universe of Plasma, in The Fourth State of Matter. 2001, Taylor & Francis.
57. States of Matter. 17 August 2016]; Available from:
http://www.chem4kids.com/files/matter_states.html.
58. 2007, a., Astrophysics Options. 2007.
59. promping, J., Study of plasmas in small tokamak experiment using integrated
predictive modeling code. 2009.
60. More History of Plasma Physics, in The Fourth State of Matter. 2001, Taylor
& Francis.
61. Admin, N., Gas Discharge Physics. 2013.
62. Hubert Rauscher, M.P., and Guy Buyle, Plasma Technology for
Hyperfunctional Surfaces. 2010.
63. Tendero, C., et al., Atmospheric pressure plasmas: A review. Spectrochimica
Acta Part B: Atomic Spectroscopy, 2006. 61(1): p. 2-30.
64. Go, P.D.B. GASEOUS IONIZATION AND ION TRANSPORT: An
Introduction to Gas Discharges. 2012.
65. Oldham, C.J., Applications of Atmospheric Plasmas, in Materials Science and
Engineering. 2009, North Carolina State University.
66. XLu, M.L.a.V.P., On atmospheric-pressure non-equilibriumplasma jets and
plasma bullets. Plasma Sources Sci. Technol, 2012. 21.
67. Sharma, V., Effects of Cold Atmospheric Pressure Plasma Jet on Viability of
Bacillus subtilis Endospores. 2013.
68. Plasma in Industry, in The Fourth State of Matter. 2001, Taylor & Francis.
69. Wende, K., et al., Risk assessment of a cold argon plasma jet in respect to its
mutagenicity. Mutation Research/Genetic Toxicology and Environmental
Mutagenesis, 2016. 798–799: p. 48-54.
70. Emanuel., D.H.a.N.M., Free-radical Theory of Aging. 1993.
71. M. Ishaq, K.B., and K. Ostrikov, Intracellular effects of atmospheric-pressure
plasmas on melanoma cancer cells. PHYSICS OF PLASMAS, 2015. 22.
49
72. Lee, H.J., et al., Inactivation of Listeria monocytogenes on agar and processed
meat surfaces by atmospheric pressure plasma jets. Food Microbiology, 2011.
28(8): p. 1468-1471.
73. Yonson, S., et al., Cell treatment and surface functionalization using a
miniature atmospheric pressure glow discharge plasma torch. Journal of
Physics D: Applied Physics, 2006. 39(16): p. 3508.
74. Seiji Kanazawa, T.F., Takeshi Nakaji, Shuichi Akamine, Ryuta Ichiki,
Measurement of OH Radicals in Aqueous Solution Produced by Atmospheric-
pressure LF Plasma Jet. IJPEST, 2012. 16.
75. al., S.e., Application of Atmospheric Microplasma for Indoor Air Treatment.
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, 2011. 47.
76. al, B.Š.e., How various plasma sources may affect seed germination and
growth. IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, 2012.
77. al, R.S.a., Atmospheric Pressure Single Electrode Argon Plasma Jet for
Biomedical Applications. International Journal of Emerging Technology and
Advanced Engineering, 2015. 5(11).
78. Tanaka, H., Cancer therapy using non-thermal atmospheric pressure plasma
with ultra-high electron density. Physics of Plasmas, 2015. 22(12): p. 122004.
79. Tanaka, H., Cancer therapy using non-thermal atmospheric pressure plasma
with ultra-high electron density. PHYSICS OF PLASMAS, 2015. 22.
80. al, H.T.e., Effectiveness of plasma treatment on pancreatic cancer cells.
INTERNATIONAL JOURNAL OF ONCOLOGY 2015. 47.
81. Hassan, A., et al., Irradiation influence on Mylar and Makrofol induced by
argon ions in a plasma immersion ion implantation system. Applied Surface
Science, 2015. 347: p. 784-792.
82. al, H.J.L.e., Inactivation of Listeria monocytogenes on agar and processed
meat surfaces by atmospheric pressure plasma jets. Food Microbiology
Inactivation of Listeria monocytogenes on agar and processed meat surfacesby
atmospheric pressure plasma jets. 28.
83. Zifan Wan, Y.C., S.K. Pankaj, Kevin M. Keener, High voltage atmospheric
cold plasma treatment of refrigerated chicken eggs for control of Salmonella
Enteritidis contamination on egg shell. Food Science and Technology, 2016.
84. Walsh, J.L. and M.G. Kong, Frequency Effects of Plasma Bullets in
Atmospheric Glow Discharges. IEEE Transactions on Plasma Science, 2008.
36(4): p. 954-955.
85. Robert J. MacNeal, M., Structure and Function of the Skin.
86. Paul A.J. Kolarsick, B., Maria Ann Kolarsick, MSN, ARNP-C, and A.-B. and
Carolyn Goodwin, FNP, SKIN CANCER.
87. Ferry, L.L., G. Argentieri, and D.H. Lochner, The comparative histology of
porcine and guinea pig skin with respect to iontophoretic drug delivery.
Pharmaceutica Acta Helvetiae, 1995. 70(1): p. 43-56.
88. al, S.D.e., Comparative histology and immunohistochemistry of porcine versus
human skin. Eur J Dermatol, 2013. 23(4): p. 456-466.
89. DEBEER, S., Comparative histology and immunohistochemistry of porcine
versus human skin. Eur J Dermatol, 2013.
90. Dermatol, E.J., Porcine Integumentary System Models.
50
91. Sooksaen, P., Smart Surfaces with Nanotechnology. Burapha Sci. J., 2011. 16:
p. 124-130.
92. NSF CAREER Award and RET Program, M.E.a.M.S., Pratt School of
Engineering, Duke University. Wetting and Contact Angle. 2013 [cited 2016
11/10/2016]; Available from:
https://www.teachengineering.org/lessons/view/duk_surfacetensionunit_less3.
93. Department of Educational Technology and Communication, N.U. Amplifier.
2008 [cited 2016 9/10/2016]; Available from:
http://www.edu.nu.ac.th/wbi/355201/p52-3.html.
94. A. Janeco, N.R.P., J. B. Branco, A. C. Ferreira, Measurement of Plasma
Power Consumption in Dielectric Barrier Discharges. ITN – Nuclear and
Technological Institute, Estrada Nacional
95. Arlee Tamman, P.S.a.Y.T., Effect of Plasma Power Control by Varied-
Voltage, Frequency and Pulse Density Modulation at Atmospheric Pressure.
2012.
96. Chung, S.J.K.a.T.H., Effects of Control Parameters on Plasma Bullet
Propagation in a Pulsed Atmospheric Pressure Argon Plasma Jet. IEEE
TRANSACTIONS ON PLASMA SCIENCE, 2011. 39: p. 2280-2281.
97. Xian-Jun Shao, G.-J.Z., Member, IEEE, Ya-Xi Li, and Gui-Min Xu,
Behaviors of Plasma Bullet Propagation and Effects of Gas Flow Rate. IEEE
TRANSACTIONS ON PLASMA SCIENCE, 2011. 39.
98. Wattieaux, G., Optical emission spectroscopy for quantification of ultraviolet
radiations and biocide active species in microwave argon plasma jet at
atmospheric pressure. Spectrochimica Acta Part B 89 (2013) 66–76, 2013.
99. Attri, P., et al., Generation mechanism of hydroxyl radical species and its
lifetime prediction during the plasma-initiated ultraviolet (UV) photolysis.
Scientific Reports, 2015. 5: p. 9332.
100. Takamatsu, T., Investigation of Reactive Species in Various Gas
PlasmasTreated Liquid and Sterilization Effects, in ISCP Conference.
120
Appendix
121
Appendix
Results Information
The results of power discharge for each 5 days in each design are showed in
the following.
1. The power discharge of design 1 at the condition 2-3 kV, 2-7 kHz and 2-5 lpm
day1
122
2. The power discharge of design 1 at the condition 2-3 kV, 2-7 kHz and 2-5 lpm
day2
3. The power discharge of design 1 at the condition 2-3 kV, 2-7 kHz and 2-5 lpm
day3
4. The power discharge of designl 1 at the condition 2-3kV, 2-7 kHz and 2-5 lpm
day4
123
5. The power discharge of design 1 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day5
6. The power discharge of design 2 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day1
124
7. The power discharge of design 2 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day2
8. The power discharge of design 2 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day3
125
9. The power discharge of design 2 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day4
10. The power discharge of design 2 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day5
126
11. The power discharge of design 3 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day1
12. The power discharge of design 3 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day2
127
13. The power discharge of design 3 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day3
14. The power discharge of design 3 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day4
128
15. The power discharge of design 3 at the condition 2-3kV, 2-7 kHz and 2-5 lpm day5
129
ANOVA METHOD : Effect of voltage on power discharge design 1
Sum of Squares df Mean Square F Sig.
Fre2kHz2lpm Between Groups .003 1 .003 46.227 .000
Within Groups .000 8 .000
Total .003 9
Fre2kHz3lpm Between Groups .003 1 .003 129.584 .000
Within Groups .000 8 .000
Total .003 9
Fre2kHz4lpm Between Groups .003 1 .003 63.873 .000
Within Groups .000 8 .000
Total .004 9
Fre2kHz5lpm Between Groups .003 1 .003 156.440 .000
Within Groups .000 8 .000
Total .003 9
Fre3kHz2lpm Between Groups .006 1 .006 70.555 .000
Within Groups .001 8 .000
Total .007 9
Fre3kHz3lpm Between Groups .005 1 .005 149.151 .000
Within Groups .000 8 .000
Total .005 9
Fre3kHz4lpm Between Groups .006 1 .006 91.032 .000
Within Groups .001 8 .000
Total .007 9
Fre3kHz5lpm Between Groups .006 1 .006 72.839 .000
Within Groups .001 8 .000
Total .007 9
Fre4kHz2lpm Between Groups .013 1 .013 94.509 .000
Within Groups .001 8 .000
Total .014 9
Fre4kHz3lpm Between Groups .012 1 .012 125.257 .000
Within Groups .001 8 .000
Total .012 9
130
Fre4kHz4lpm Between Groups .011 1 .011 94.938 .000
Within Groups .001 8 .000
Total .012 9
Fre4kHz5lpm Between Groups .013 1 .013 110.505 .000
Within Groups .001 8 .000
Total .014 9
Fre5kHz2lpm Between Groups .024 1 .024 69.541 .000
Within Groups .003 8 .000
Total .027 9
Fre5kHz3lpm Between Groups .022 1 .022 111.022 .000
Within Groups .002 8 .000
Total .023 9
Fre5kHz4lpm Between Groups .021 1 .021 80.179 .000
Within Groups .002 8 .000
Total .024 9
Fre5kHz5lpm Between Groups .023 1 .023 96.850 .000
Within Groups .002 8 .000
Total .025 9
Fre6kHz2lpm Between Groups .029 1 .029 70.358 .000
Within Groups .003 8 .000
Total .032 9
Fre6kHz3lpm Between Groups .031 1 .031 71.604 .000
Within Groups .003 8 .000
Total .035 9
Fre6kHz4lpm Between Groups .032 1 .032 149.800 .000
Within Groups .002 8 .000
Total .033 9
Fre6kHz5lpm Between Groups .033 1 .033 70.716 .000
Within Groups .004 8 .000
Total .036 9
Fre7kHz2lpm Between Groups .042 1 .042 106.747 .000
Within Groups .003 8 .000
Total .046 9
131
Fre7kHz3lpm Between Groups .046 1 .046 107.226 .000
Within Groups .003 8 .000
Total .049 9
Fre7kHz4lpm Between Groups .053 1 .053 161.510 .000
Within Groups .003 8 .000
Total .055 9
Fre7kHz5lpm Between Groups .045 1 .045 69.240 .000
Within Groups .005 8 .001
Total .050 9
132
ANOVA METHOD : Effect of voltage on power discharge design 2
Sum of Squares df Mean Square F Sig.
Fre2kHz2lpm Between Groups .002 1 .002 9.680 .014
Within Groups .001 8 .000
Total .003 9
Fre2kHz3lpm Between Groups .002 1 .002 10.058 .013
Within Groups .001 8 .000
Total .003 9
Fre2kHz4lpm Between Groups .002 1 .002 13.697 .006
Within Groups .001 8 .000
Total .003 9
Fre2kHz5lpm Between Groups .002 1 .002 3.747 .089
Within Groups .004 8 .000
Total .006 9
Fre3kHz2lpm Between Groups .004 1 .004 13.896 .006
Within Groups .002 8 .000
Total .006 9
Fre3kHz3lpm Between Groups .004 1 .004 13.821 .006
Within Groups .002 8 .000
Total .006 9
Fre3kHz4lpm Between Groups .004 1 .004 10.039 .013
Within Groups .003 8 .000
Total .007 9
Fre3kHz5lpm Between Groups .001 1 .001 1.229 .300
Within Groups .006 8 .001
Total .007 9
Fre4kHz2lpm Between Groups .008 1 .008 12.620 .007
Within Groups .005 8 .001
Total .013 9
Fre4kHz3lpm Between Groups .006 1 .006 11.015 .011
Within Groups .005 8 .001
Total .011 9
133
Fre4kHz4lpm Between Groups .007 1 .007 11.202 .010
Within Groups .005 8 .001
Total .012 9
Fre4kHz5lpm Between Groups .003 1 .003 1.373 .275
Within Groups .015 8 .002
Total .018 9
Fre5kHz2lpm Between Groups .014 1 .014 13.753 .006
Within Groups .008 8 .001
Total .022 9
Fre5kHz3lpm Between Groups .012 1 .012 12.019 .008
Within Groups .008 8 .001
Total .021 9
Fre5kHz4lpm Between Groups .013 1 .013 10.906 .011
Within Groups .009 8 .001
Total .022 9
Fre5kHz5lpm Between Groups .004 1 .004 1.286 .290
Within Groups .028 8 .003
Total .032 9
Fre6kHz2lpm Between Groups .021 1 .021 12.412 .008
Within Groups .013 8 .002
Total .034 9
Fre6kHz3lpm Between Groups .019 1 .019 11.470 .010
Within Groups .013 8 .002
Total .032 9
Fre6kHz4lpm Between Groups .018 1 .018 10.970 .011
Within Groups .013 8 .002
Total .031 9
Fre6kHz5lpm Between Groups .005 1 .005 .831 .389
Within Groups .045 8 .006
Total .049 9
Fre7kHz2lpm Between Groups .027 1 .027 11.938 .009
Within Groups .018 8 .002
Total .046 9
134
Fre7kHz3lpm Between Groups .021 1 .021 13.971 .006
Within Groups .012 8 .002
Total .033 9
Fre7kHz4lpm Between Groups .024 1 .024 13.269 .007
Within Groups .015 8 .002
Total .039 9
Fre7kHz5lpm Between Groups .005 1 .005 .859 .381
Within Groups .047 8 .006
Total .052 9
135
ANOVA METHOD : Effect of voltage on power discharge design 3
Sum of Squares df Mean Square F Sig.
Fre2kHz2lpm Between Groups .000 1 .000 16.937 .003
Within Groups .000 8 .000
Total .000 9
Fre2kHz3lpm Between Groups .000 1 .000 17.138 .003
Within Groups .000 8 .000
Total .000 9
Fre2kHz4lpm Between Groups .000 1 .000 174.509 .000
Within Groups .000 8 .000
Total .000 9
Fre2kHz5lpm Between Groups .000 1 .000 169.945 .000
Within Groups .000 8 .000
Total .000 9
Fre3kHz2lpm Between Groups .000 1 .000 15.117 .005
Within Groups .000 8 .000
Total .001 9
Fre3kHz3lpm Between Groups .000 1 .000 17.002 .003
Within Groups .000 8 .000
Total .001 9
Fre3kHz4lpm Between Groups .001 1 .001 141.425 .000
Within Groups .000 8 .000
Total .001 9
Fre3kHz5lpm Between Groups .001 1 .001 191.693 .000
Within Groups .000 8 .000
Total .001 9
Fre4kHz2lpm Between Groups .001 1 .001 14.749 .005
Within Groups .000 8 .000
Total .001 9
Fre4kHz3lpm Between Groups .001 1 .001 16.763 .003
Within Groups .001 8 .000
Total .002 9
136
Fre4kHz4lpm Between Groups .001 1 .001 151.151 .000
Within Groups .000 8 .000
Total .002 9
Fre4kHz5lpm Between Groups .001 1 .001 322.808 .000
Within Groups .000 8 .000
Total .001 9
Fre5kHz2lpm Between Groups .001 1 .001 14.085 .006
Within Groups .001 8 .000
Total .002 9
Fre5kHz3lpm Between Groups .002 1 .002 14.058 .006
Within Groups .001 8 .000
Total .003 9
Fre5kHz4lpm Between Groups .003 1 .003 79.484 .000
Within Groups .000 8 .000
Total .003 9
Fre5kHz5lpm Between Groups .003 1 .003 202.152 .000
Within Groups .000 8 .000
Total .003 9
Fre6kHz2lpm Between Groups .003 1 .003 17.082 .003
Within Groups .001 8 .000
Total .004 9
Fre6kHz3lpm Between Groups .003 1 .003 17.077 .003
Within Groups .001 8 .000
Total .004 9
Fre6kHz4lpm Between Groups .003 1 .003 233.233 .000
Within Groups .000 8 .000
Total .004 9
Fre6kHz5lpm Between Groups .003 1 .003 147.267 .000
Within Groups .000 8 .000
Total .003 9
Fre7kHz2lpm Between Groups .003 1 .003 12.615 .007
Within Groups .002 8 .000
Total .005 9
137
Fre7kHz3lpm Between Groups .003 1 .003 17.626 .003
Within Groups .001 8 .000
Total .005 9
Fre7kHz4lpm Between Groups .005 1 .005 206.589 .000
Within Groups .000 8 .000
Total .005 9
Fre7kHz5lpm Between Groups .005 1 .005 189.806 .000
Within Groups .000 8 .000
Total .005 9
138
ANOVA METHOD : Effect of frequency on power discharge design 1
Sum of Squares df Mean Square F Sig.
volt2kV2lpm Between Groups .008 5 .002 26.651 .000
Within Groups .001 24 .000
Total .009 29
volt2kV3lpm Between Groups .007 5 .001 44.894 .000
Within Groups .001 24 .000
Total .007 29
volt2kV4lpm Between Groups .007 5 .001 33.940 .000
Within Groups .001 24 .000
Total .008 29
volt2kV5lpm Between Groups .006 5 .001 42.135 .000
Within Groups .001 24 .000
Total .007 29
volt3kV2lpm Between Groups .073 5 .015 34.704 .000
Within Groups .010 24 .000
Total .083 29
volt3kV3lpm Between Groups .077 5 .015 41.134 .000
Within Groups .009 24 .000
Total .086 29
volt3kV4lpm Between Groups .083 5 .017 54.511 .000
Within Groups .007 24 .000
Total .090 29
volt3kV5lpm Between Groups .071 5 .014 28.562 .000
Within Groups .012 24 .000
Total .082 29
139
ANOVA METHOD : Effect of frequency on power discharge design 2
Sum of Squares df Mean Square F Sig.
volt2kV2lpm Between Groups .003 5 .001 5.768 .001
Within Groups .002 24 .000
Total .005 29
volt2kV3lpm Between Groups .004 5 .001 6.236 .001
Within Groups .003 24 .000
Total .006 29
volt2kV4lpm Between Groups .003 5 .001 4.558 .005
Within Groups .003 24 .000
Total .006 29
volt2kV5lpm Between Groups .014 5 .003 .844 .532
Within Groups .077 24 .003
Total .090 29
volt3kV2lpm Between Groups .042 5 .008 4.404 .005
Within Groups .046 24 .002
Total .088 29
volt3kV3lpm Between Groups .036 5 .007 4.482 .005
Within Groups .039 24 .002
Total .075 29
volt3kV4lpm Between Groups .036 5 .007 4.089 .008
Within Groups .043 24 .002
Total .079 29
volt3kV5lpm Between Groups .027 5 .005 1.941 .125
Within Groups .067 24 .003
Total .095 29
140
ANOVA METHOD : Effect of frequency on power discharge design 3
Sum of Squares df Mean Square F Sig.
volt2kV2lpm Between Groups .001 5 .000 60.190 .000
Within Groups .000 24 .000
Total .001 29
volt2kV3lpm Between Groups .001 5 .000 21.844 .000
Within Groups .000 24 .000
Total .001 29
volt2kV4lpm Between Groups .001 5 .000 49.979 .000
Within Groups .000 24 .000
Total .001 29
volt2kV5lpm Between Groups .001 5 .000 50.555 .000
Within Groups .000 24 .000
Total .001 29
volt3kV2lpm Between Groups .008 5 .002 7.530 .000
Within Groups .005 24 .000
Total .013 29
volt3kV3lpm Between Groups .006 5 .001 6.890 .000
Within Groups .004 24 .000
Total .011 29
volt3kV4lpm Between Groups .008 5 .002 56.724 .000
Within Groups .001 24 .000
Total .008 29
volt3kV5lpm Between Groups .007 5 .001 72.059 .000
Within Groups .000 24 .000
Total .008 29
141
ANOVA METHOD : Effect of argon flowrate on power discharge design 1
Sum of Squares df Mean Square F Sig.
Volt2kV2kHz Between Groups .000 3 .000 .278 .840
Within Groups .000 16 .000
Total .000 19
Volt2kV3kHz Between Groups .000 3 .000 .269 .847
Within Groups .000 16 .000
Total .000 19
Volt2kV4kHz Between Groups .000 3 .000 .450 .721
Within Groups .001 16 .000
Total .001 19
Volt2kV5kHz Between Groups .000 3 .000 .951 .440
Within Groups .001 16 .000
Total .001 19
Volt2kV6kHz Between Groups .000 3 .000 .252 .858
Within Groups .001 16 .000
Total .001 19
Volt2kV7kHz Between Groups .000 3 .000 .615 .615
Within Groups .001 16 .000
Total .001 19
Volt3kV2kHz Between Groups .000 3 .000 .091 .964
Within Groups .001 16 .000
Total .001 19
Volt3kV3kHz Between Groups .000 3 .000 .283 .837
Within Groups .002 16 .000
Total .002 19
Volt3kV4kHz Between Groups .000 3 .000 .226 .877
Within Groups .003 16 .000
Total .003 19
Volt3kV5kHz Between Groups .000 3 .000 .192 .900
Within Groups .007 16 .000
Total .008 19
142
Volt3kV6kHz Between Groups .000 3 .000 .095 .962
Within Groups .011 16 .001
Total .011 19
Volt3kV7kHz Between Groups .001 3 .000 .212 .886
Within Groups .014 16 .001
Total .014 19
143
ANOVA METHOD : Effect of argon flowrate on power discharge design 2
Sum of Squares df Mean Square F Sig.
Volt2kV2kHz Between Groups .001 3 .000 1.191 .345
Within Groups .002 16 .000
Total .003 19
Volt2kV3kHz Between Groups .001 3 .000 1.077 .387
Within Groups .003 16 .000
Total .004 19
Volt2kV4kHz Between Groups .002 3 .001 1.216 .336
Within Groups .008 16 .001
Total .010 19
Volt2kV5kHz Between Groups .003 3 .001 1.140 .363
Within Groups .016 16 .001
Total .020 19
Volt2kV6kHz Between Groups .005 3 .002 .991 .422
Within Groups .027 16 .002
Total .032 19
Volt2kV7kHz Between Groups .007 3 .002 1.255 .323
Within Groups .028 16 .002
Total .035 19
Volt3kV2kHz Between Groups .001 3 .000 .604 .622
Within Groups .005 16 .000
Total .006 19
Volt3kV3kHz Between Groups .000 3 .000 .081 .969
Within Groups .010 16 .001
Total .010 19
Volt3kV4kHz Between Groups .000 3 .000 .024 .995
Within Groups .022 16 .001
Total .022 19
Volt3kV5kHz Between Groups .000 3 .000 .009 .999
Within Groups .037 16 .002
Total .037 19
144
Volt3kV6kHz Between Groups .000 3 .000 .032 .992
Within Groups .057 16 .004
Total .058 19
Volt3kV7kHz Between Groups .001 3 .000 .061 .979
Within Groups .063 16 .004
Total .064 19
145
ANOVA METHOD : Effect of argon flowrate on power discharge design 3
Sum of Squares df Mean Square F Sig.
Volt2kV2kHz Between Groups .000 3 .000 .763 .531
Within Groups .000 16 .000
Total .000 19
Volt2kV3kHz Between Groups .000 3 .000 2.406 .105
Within Groups .000 16 .000
Total .000 19
Volt2kV4kHz Between Groups .000 3 .000 2.174 .131
Within Groups .000 16 .000
Total .000 19
Volt2kV5kHz Between Groups .000 3 .000 3.718 .033
Within Groups .000 16 .000
Total .000 19
Volt2kV6kHz Between Groups .000 3 .000 2.181 .130
Within Groups .000 16 .000
Total .000 19
Volt2kV7kHz Between Groups .000 3 .000 2.985 .062
Within Groups .000 16 .000
Total .000 19
Volt3kV2kHz Between Groups .000 3 .000 .356 .786
Within Groups .000 16 .000
Total .000 19
Volt3kV3kHz Between Groups .000 3 .000 .682 .576
Within Groups .000 16 .000
Total .001 19
Volt3kV4kHz Between Groups .000 3 .000 .326 .806
Within Groups .001 16 .000
Total .001 19
Volt3kV5kHz Between Groups .000 3 .000 .427 .737
Within Groups .002 16 .000
Total .002 19
146
Volt3kV6kHz Between Groups .000 3 .000 .124 .945
Within Groups .003 16 .000
Total .003 19
Volt3kV7kHz Between Groups .000 3 .000 .175 .912
Within Groups .004 16 .000
Total .004 19
The results of power plasma plume length for 5 days for each design are showed
in the following.
16. The plasma plume length of design 1 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day1
147
17. The plasma plume length of design 2 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day2
18. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day3
148
19. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day4
20. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day5
149
21. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day1
22. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day2
150
23. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day3
24. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day4
151
25. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day5
26. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day1
152
27. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day2
28. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day3
153
29. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day3
30. The plasma plume length of design 3 at the condition 2-3 kV, 2-7 kHz and 2-5
lpm day5
154
Corelation result : Between voltage versus frequency and flowrate of design 1
155
Corelation result : Between voltage versus frequency and flowrate of design 2
156
Corelation result : Between voltage versus frequency and flowrate of design 3
157
The results of power plasma plume length for 5 days for each design are showed
in the following.
31. The OES result of plasma jet design 1 in condition 2kV, 2lpm and 2–7 kHz
at Day 1
158
32. The OES result of plasma jet designl 1 in condition 2kV, 2lpm and 2–7 kHz
at Day 2
159
33. The OES result of plasma jet design 1 in condition 2kV, 2lpm and 2–7 kHz
at Day 3
160
34. The OES result of plasma jet design 1 in condition 2kV, 2lpm and 2–7 kHz
at Day 4
161
35. The OES result of plasma jet design 1 in condition 2kV, 2lpm and 2–7 kHz
at Day 5
162
36. The OES result of plasma jet design 1 in condition 3kV, 2lpm and 2–7 kHz
at Day 1
163
37. The OES result of plasma jet design 1 in condition 3kV, 2lpm and 2–7 kHz
at Day 2
164
38. The OES result of plasma jet design 1 in condition 3kV, 2lpm and 2–7 kHz
at Day 3
165
39. The OES result of plasma jet design 1 in condition 3kV, 2lpm and 2–7 kHz
at Day 4
166
40. The OES result of plasma jet design 1 in condition 3kV, 2lpm and 2–7 kHz
at Day 5
167
41. The OES result of plasma jet design 2 in condition 2kV, 2lpm and 2–7 kHz
at Day 1
168
42. The OES result of plasma jet design 2 in condition 2kV, 2lpm and 2–7 kHz
at Day 2
169
43. The OES result of plasma jet design 2 in condition 2kV, 2lpm and 2–7 kHz
at Day 3
170
44. The OES result of plasma jet design 2 in condition 2kV, 2lpm and 2–7 kHz
at Day 4
171
45. The OES result of plasma jet design 2 in condition 2kV, 2lpm and 2–7 kHz
at Day 5
172
46. The OES result of plasma jet design 2 in condition 3kV, 2lpm and 2–7 kHz
at Day 1
173
47. The OES result of plasma jet design 2 in condition 3kV, 2lpm and 2–7 kHz
at Day 2
174
48. The OES result of plasma jet design 2 in condition 3kV, 2lpm and 2–7 kHz
at Day 3
175
49. The OES result of plasma jet design 2 in condition 3kV, 2lpm and 2–7 kHz
at Day 4
176
50. The OES result of plasma jet design 2 in condition 3kV, 2lpm and 2–7 kHz
at Day 5
177
51. The OES result of plasma jet design 3 in condition 2kV, 2lpm and 2–7 kHz
at Day 1
178
52. The OES result of plasma jet design 3 in condition 2kV, 2lpm and 2–7 kHz
at Day 2
179
53. The OES result of plasma jet design 3 in condition 2kV, 2lpm and 2–7 kHz
at Day 3
180
54. The OES result of plasma jet design 3 in condition 2kV, 2lpm and 2–7 kHz
at Day 4
181
55. The OES result of plasma jet design 3 in condition 2kV, 2lpm and 2–7 kHz
at Day 5
182
56. The OES result of plasma jet design 3 in condition 3kV, 2lpm and 2–7 kHz
at Day 1
183
57. The OES result of plasma jet design 3 in condition 3kV, 2lpm and 2–7 kHz
at Day 2
184
58. The OES result of plasma jet design 3 in condition 3kV, 2lpm and 2–7 kHz
at Day 3
185
59. The OES result of plasma jet design 3 in condition 3kV, 2lpm and 2–7 kHz
at Day 4
186
60. The OES result of plasma jet design 3 in condition 3kV, 2lpm and 2–7 kHz
at Day 5
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