The Solubility of Natural Cellulose After DBD Plasma Treatment

Natural cellulose was treated by an atmospheidc DBD plasma. The solubility of cellulose in a diluted alkaline solution after the plasma treatment was investigated. The properties were characterized by X-ray photoelectron spectroscopy （XPS）, Fourier-transform infrared spectroscopy （FTIR） and scanning electron microscopy （SEM）. The results indicated that the surface of cellulose treated by the argon DBD plasma was significantly etched, and the relevant force of hydrogen bonding was decreased. This might be the essential reason for the solubility improvement of natural cellulose in the diluted alkaline solution. Through a comparison of two discharge modes, the atmospheric DBD plasma gun and the parallel plate capacitively coupled DBD plasma, it was found that the atmospheric DBD plasma gun was more effective in fragmentizing the cellulose due to its production of a high energy plasma based on its special structure.     

Yield of H2O2in Gas-Liquid Phase with Pulsed DBD简

Electric discharge in water can generate a large number of oxidants such as ozone, hydrogen peroxide and hydroxyl radicals. In this paper, a non-thermal plasma processing system was established by means of pulsed dielectric barrier discharge in gas-liquid phase. The electrodes of discharge reactor were staggered. The yield of H2O2 was enhanced after discharge. The effects of discharge time, discharge voltage, frequency, initial pH value, and feed gas were investigated. The concentration of hydrogen peroxide and ozone was measured after discharge. The experimental results were fully analyzed. The chemical reaction equations in water were given as much as possible. At last, the water containing Rhodamine B was tested in this system. The degradation rate came to 94.22% in 30 min.     

Impact of Ion Implantation on Licorice （Glycyrrhiza uralensis Fisch） Growth and Antioxidant Activity Under Drought Stress

Low energy ion beams are known to have stimulation effects on plant generation and to improve plants＇ intrinsic quality. In the present study, the growth and physiological index of licorice implanted with 0, 8, 10; 12 and 14× （2.6× 10^15） ions/cm^2 were investigated under well-watered and drought-stress conditions. The results showed that a proper dose of ion implan- tation was particularly efficient in stimulating the licorice growth and improving the plant biomass significantly in both the well-watered and drought-stress conditions. The physiological results of licorice measured by leaf water potential, lipid oxidation, soluble protein and antioxidant system showed a significant correlation between ion implantation and water regime except for leaf water potential. Therefore, the study indicated that ion implantation can enhance licorice＇s drought tolerance by increasing the activity of superoxide dismutase （SOD）, eatalase （CAT） and DPPH （1,1-diphenyl-2-picrylhydrazyl） radical scavenging ability to lower oxidative damage to lipids in plants. Ion beam implantation, therefore, provides an alternative method to enhance licorice drought tolerance.     

Deep Desulfurization of Diesel Fuels with Plasma/Air as Oxidizing Medium,Diperiodatocuprate （III） as Catalyzer and Ionic Liquid as Extraction Solvent

In this paper, the oxidative desulfurization （ODS） system is directly applied to deal with the catalytic oxidation of sulfur compounds of sulfur-containing model oil by dielectric barrier discharge （DBD） plasma in the presence of air plus an extraction step with the oxidation-treated fuel put over ionic liquid [BMIM]FeC14 （1-butyl-3-methylimidazolium tetrachloroferrate）. This new system exhibited an excellent desulfurization effect. The sulfur content of DBT in diesel oil decreased from 200 ppm to 4.92 ppm （S removal rate up to 97.5%） under the following optimal reaction conditions： air flow rate （v） of 60 mL/min, amplitude of applied voltage （U） on DBD of 16 kV, input frequency （f） of 79 kHz, catalyst amount （w） of 1.25 wt%, reaction time （t） of 10 min. Moreover, a high desulfurization rate was obtained during oxidation of benzothiophene （BT） or 4,6-DMDBT （4,6-dimethyl-dibenzothiophene） under the aforementioned conditions. The oxidation reactivity of different S compounds was decreased in the order of DBT, 4,6-DMDBT and BT. The remarkable advantage of the novel ODS system is that the desulfurization condition applies in the presence of air at ambient conditions without peroxides, aqueous solvent or biphasic oil-aqueous solution system.     

Oxidation of S（IV） in Seawater by Pulsed High Voltage Discharge Plasma with TiO2/Ti Electrode as Catalyst

Oxidation of S（IV） to S（VI） in the effluent of a flue gas desulfurization（FGD） sys- tem is very critical for industrial applications of seawater FGD. This paper reports a pulsed corona discharge oxidation process combined with a TiO2 photocatalyst to convert S（IV） to S（VI） in artificial seawater. Experimental results show that the oxidation of S（IV） in artificial seawater is enhanced in the pulsed discharge plasma process through the application of TiO2 coating electrodes. The oxidation rate of S（IV） using Ti metal as a ground electrode is about 2.0x10-4 mol. L 1. min-1, the oxidation rate using TiO2/Ti electrode prepared by annealing at 500 ~C in air is 4.5x 10-4 tool. L-a ~ min-1, an increase with a factor 2.25. The annealing temper- ature for preparing TiO2/Ti electrode has a strong effect on the oxidation of S（IV） in artificial seawater. The results of in-situ emission spectroscopic analysis show that chemically active species （i.e. hydroxyl radicals and oxygen radicals） are produced in the pulsed discharge plasma process. Compared with the traditional air oxidation process and the sole plasma-induced oxidation process, the combined application of TiO2 photocatalysts and a pulsed high-voltage electrical discharge process is useful in enhancing the energy and conversion efficiency of S（IV） for the seawater FGD system.     

Heat Transfer During Radio Frequency Inductively Coupled Plasma Deposition of Tungsten

Particle melting and substrate temperature are important in controlling deposited density and residual stress in thermal plasma deposition of refractory materials. In this paper, both the heating and cooling behaviours of tungsten particles inside a radio frequency inductively coupled plasma （ICP） and the plasma heat flux to the substrate were investigated. The distribution of the plasma-generated heat on device, powder injection probe, deposition chamber, and substrate was determined by measuring the water flow rate and the flow-in and flow-out water temperatures in the four parts. Substrate temperature was measured by a two-colour pyrometer during the ICP deposition of tungsten. Experimental results show that the heat flux to the substrate accounts for about 20% of the total plasma energy, the substrate temperature can reach as high as 2100 K, and the heat loss by radiation is significant in the plasma deposition of tungsten.     

Effects of Finite Aspect Ratio and Noncircular Plasma Flux Surface on Electron Temperature Gradient Driven Modesd

A gyrokinetic model with integral eigenmode equations is developed based on the local equilibrium of shaped tokamak plasmas. Effects of main geometric parameters （finite aspect ratio, elongation, triangularity, and Shafranov shift gradient） on the electrostatic electron temper- ature gradient （ETG） driven modes are investigated numerically. It is found that the finite aspect ratio has a general stabilizing effect, while the elongation can be either stabilizing or destabilizing, depending on the poloidal wavelength of the mode and other parameters. It is shown that a low aspect ratio enhances the stabilizing effect of elongation, and weakens its destabilizing effect as well.     

Mutation-Screening of Pleurotus Ferulae with High Temperature Tolerance by Nitrogen Ion Implantation

In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 -15 keV and dose of 1.5×10^15 - 1.5 × 10^16 cm^-2, and a mutant CGMCC1763 was isolated subsequently through thermotolerant screening method. It was found that during riper period the surface layer mycelium of the mutant in mushroom bag wasn＇t aging neither grew tegument even above 30℃. The mycelium endurable temperature of the mutant was increased by 5℃ compared to that of the wild type strain. The fruiting bodies growth temperature of the mutant was 18 -22℃ in daytime and 8 -14℃ at night. The highest growth temperature of fruiting bodies of the mutant was increased about 7℃ w.r.t, that of original strain. Through three generations investigations, it was found that the mutant CGMCC1763 was stable with high temperature tolerance.     

Analysis and Performance of the Thomson Scattering Diagnostics on HT-7 Tokamak Based on I-EMCCD

A visible light imaging Thomson scattering （VIS-TVTS） diagnostic system has been developed for the measurement of plasma electron temperature on the HT-7 tokamak. The system contains a Nd：YAG laser （A = 532 nm, repetition rate 10 Hz, total pulse duration ≈ 10 ns, pulse energy 〉 1.0 J）, a grating spectrometer, an image intensifier （I.I.） lens coupled with an electron multiplying CCD （EMCCD） and a data acquisition and analysis system. In this paper, the measurement capability of the system is analyzed. In addition to the performance of the system, the capability of measuring plasma electron temperature has been proved. The profile of electron temperature is presented with a spatial resolution of about 0.96 cm （seven points） near the center of the plasma.     

Design of the material performance test apparatus for high temperature gas-cooled reactor

Most materials can be easily corroded or ineffective in carbonaceous atmospheres at high temperatures in the reactor core of the high temperature gas-cooled reactor （HTGR）. To solve the problem, a material performance test apparatus was built to provide reliable materials and technical support for relevant experiments of the HTGR. The apparatus uses a center high-purity graphite heater and surrounding thermal insulating layers made of carbon fiber felt to form a strong carbon reducing atmosphere inside the apparatus. Specially designed tungsten rhenium thermocouples which can endure high temperatures in carbonaceous atmospheres are used to control the temperature field. A typical experimental process was analyzed in the paper, which lasted 76 hours including seven stages. Experimental results showed the test apparatus could completely simulate the carbon reduction atmosphere and high temperature environment the same as that confronted in the real reactor and the performance of screened materials had been successfully tested and verified. Test temperature in the apparatus could be elevated up to 1600℃, which covered the whole temperature range of the normal operation and accident condition of HTGR and could fully meet the test reauirements of materials used in the reactor.     

Creation of High-Yield Polyhydroxyalkanoates Engineered Strains by Low Energy Ion Implantation

Polyhydroxyalkanoates （PHAs）, as a candidate for biodegradable plastic materials, can be synthesized by numerous microorganisms. However, as its production cost is high in comparison with those of chemically synthesized plastics, a lot of research has been focused on the efficient production of PHAs using different methods. In the present study, the mutation effects of PHAs production in strain pCB4 were investigated with implantation of low energy ions. It was found that under the implantation conditions of 7.8×10^14 N^＋/cm^2 at 10 keV, a high-yield PHAs strain with high genetic stability was generated from many mutants. After optimizing its fermentation conditions, the biomass, PHAs concentration and PHAs content of pCBH4 reached 2.26 g/L, 1.81 g/L, and 80.08% respectively, whereas its wild type controls were about 1.24 g/L, 0.61 g/L, and 49.20%. Moreover, the main constituent of PHAs was identified as poly-3-hydroxybutyrates （PHB） in the mutant stain and the yield of this compound was increased up to 41.33% in contrast to that of 27.78% in the wild type strain.     

Temperature and Nitric Oxide Generation in a Pulsed Arc Discharge Plasma

Nitric oxide （NO） is increasingly being used in medical treatments of high blood pressure, acute respiratory distress syndrome and other illnesses related to the lungs. Currently a NO inhalation system consists of a gas cylinder of N2 mixed with a high concentration of NO. This arrangement is potentially risky due to the possibility of an accidental leak of NO from the cylinder. The presence of NO in the air leads to the formation of nitric dioxide （NO2）, which is toxic to the lungs. Therefore, an on-site generator of NO would be highly desirable for medical doctors to use with patients with lung disease.
To develop the NO inhalation system without a gas cylinder, which would include a high concentration of NO, NAMIHIRA et al have recently reported on the production of NO from room air using a pulsed arc discharge. In the present work, the temperature of the pulsed arc discharge plasma used to generate NO was measured to optimize the discharge condition. The results of the temperature measurements showed the temperature of the pulsed arc discharge plasma reached about 10,000 K immediately after discharge initiation and gradually decreased over tens of microseconds. In addition, it was found that NO was formed in a discharge plasma having temperatures higher than 9,000 K and a smaller input energy into the discharge plasma generates NO more efficiently than a larger one.     

Diagnosis of Electronic Excitation Temperature in Surface Dielectric Barrier Discharge Plasmas at Atmospheric Pressure

The electronic excitation temperature of a surface dielectric barrier discharge （DBD） at atmospheric pressure has been experimentally investigated by optical emission spectroscopic measurements combined with numerical simulation. Experiments have been carried out to deter- mine the spatial distribution of electric field by using FEM software and the electronic excitation temperature in discharge by calculating ratio of two relative intensities of atomic spectral lines. In this work, we choose seven Ar atomic emission lines at 415.86 nm [（3s^23p^5）5p →（3s^23p^5）4s] and 706.7 nm, 714.7 nm, 738.4 nm, 751.5 nm, 794.8 nm and 800.6 nm [（3s^23p^5）4p → （3s^23p^5）4s] to estimate the excitation temperature under a Boltzmann approximation. The average electron energy is evaluated in each discharge by using line ratio of 337.1 nm （N2（C^3Пu →B3Пg）） to 391.4 nm （N2^＋（B2 ∑u^＋→ ∑g^＋））. Furthermore, variations of the electronic excitation tempera- ture are presented versus dielectric thickness and dielectric materials. The discharge is stable and uniform along the axial direction, and the electronic excitation temperature at the edge of the copper electrode is the largest. The corresponding average electron energy is in the range of 1.6- 5.1 eV and the electric field is in 1.7-3.2 MV/m, when the distance from copper electrode varies from 0 cm to 6 cm. Moreover, the electronic excitation temperature with a higher permittivity leads to a higher dissipated electrical power.     

Photon Temperatures of Hard X-Ray Emission of LHCD Plasmas in HT-7 Tokamak

A detailed study of photon temperatures （Tph） of hard X-ray emission in lower hybrid current drive （LHCD） plasmas is presented. The photon temperature increases with the increase in plasma current and decreases with the increase in plasma density. In lower hybrid power and phase scanning experiments; there is no appreciable change in the photon temperature. The numerical results based on ray-tracing calculation and Fokker-Planck solver gives reasonable explanation for the experimental observation. Both experimental and numerical results reveal that the photon temperature depends mainly on global effects of the fast electron population, synergy between the fast electron and the loop voltage and the Coulomb slowing down.     

Spectroscopic Methods for Determination of Excitation Temperatures of High-Pressure Plasma

A method to determine excitation temperatures based on the optical emission spectroscopy （OES） and Fermi-Dirac distribution was set up, and the temperatures of pure-argon and mixed-gases at different pressures were investigated. In this way we set up a standard process to get the excitation temperatures of plasmas operated at atmospheric and sub-atmospheric pressures.     

Bioeffects of Low Energy Ion Beam Implantation： DNA Damage, Mutation and Gene Transter

Low-energy ion beam implantation （10 - 200 keV） has been proved to have a wide range of biological effects and is broadly used in the breeding of crops and micro-organisms.To understand its mechanisms better and facilitate its applications, the developments in the bioeffects of low energy ion beam implantation in the past twenty years are summarized in this paper.     

Room Temperature Growth of Hydrogenated Amorphous Silicon Films by Dielectric Barrier Discharge Enhanced CVD

Hydrogenated amorphous silicon （a-Si： H） films were deposited on Si （100） and glass substrates by dielectric barrier discharge enhanced chemical vapour deposition （DBD-CVD） in （SiH4＋H2） atmosphere at room temperature.
Results of the thickness measurement, SEM （scanning electron microscope）, Raman, and FTIR （Fourier transform infrared spectroscopy） show that with the increase in the applied peak voltage, the deposition rate and network order of the films increase, and the hydrogen bonding configurations mainly in di-hydrogen （Si-H2） and poly hydrogen （SiH2）n are introduced into the films. The UV-visible transmission spectra show that with the decrease in SiH4/ （SiHn＋H2） the thin films＇ band gap shifts from 1.92 eV to 2.17 eV.
These experimental results are in agreement with the theoretic analysis of the DBD discharge. The deposition of a-Si： H films by the DBD-CVD method as reported here for the first time is attractive because it allows fast deposition of a-Si： H films on large-area low-melting-point substrates and requires only a low cost of production without additional heating or pumping equipment.     

Comparison between nuclear thermometers in central Xe＋Sn collision

The temperature of fragmenting source in central heavy-ion collisions at Fermi energy is investigated by the isospin-dependent quantum molecular dynamics model in combination with the statistical decay model GEMINI. Five different nuclear thermometers are used to extract nuclear temperature. We find that the He and Li isotope temperature reaches a plateau at about 70-100 MeV/nucleon of beam energy. The slope temperature and the quadrupole fluctuation temperature give high values. The quantum slope temperature and the quantum quadrupole fluctuation temperature are more close to the He and Li isotope temperatures.     

Influence of Jet Angle and Ion Density of Cathode Side on Low Current Vacuum Arc Characteristics

In this study, the influence of the initial jet angles （IJAs） and ion number densities （INDs） at the cathode side on the low current vacuum arc （LCVA） characteristics is simulated and analysed. The results show that the ion temperature, electron temperature, ion number density, axial current density and plasma pressure all decrease with the increase of the cathode IJAs. It is also shown that LCVA can cause a current constriction for lower cathode IND, and the anode sheath potential is more nonuniform, which is mainly related to the nonuniform distribution of the axial current density at the anode side.     

IMF production and symmetry energy in heavy ion collisions near Fermi energy

The symmetry energy at the time of the production of intermediate mass fragments （IMFs） is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations （QSM of Hahn and Stfcker）. The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,（μt- μp） /T, and the double ratio temperature, T, were extracted experimentally in the reactions of 64＇7~Zn, 64Ni＋58＇64Ni, 112＇124Sn, 197Au, 232Th at 40A MeV. The extracted （μt- μp） / T scales linearly with Jwv, where fi~v is the asymmetry parameter, （N-Z）/A, of the emitting source and （μt- μp） / T = （11.1 ＋ 1.4）rNN -- 0.21 was derived. The experimentally extracted （μt-μp）/T and the double ratio temperatures are compared with those from the QSM calculations. The temperatures, T, and densities, p, extracted from the （μn - μp） / T values agreed with those from the double ratio thermometer which used the yield ratios of d, t, h and a particles. However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and p. T=5.25±0.75 MeV is evaluated from the （μn -μp） / T analysis, but no density determination was possible. From the extracted T value, the symmetry energy coefficient Esym=14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV.