Investigation of Microwave Surface-Wave Plasma Deposited SiOxCoatings on Polymeric Substrates简

In this paper, we reported nano-scale SiOx coatings deposited on polyethylene terephthalate （PET） webs by microwave surface-wave assisted plasma enhanced chemical vapor deposition for the purpose of improving their barrier properties. Oxygen （O2） and hexamethyl- disiloxane （HMDSO） were employed as oxidant gas and Si monomer during SiOx deposition, re- spectively. Analysis by Fourier transform infrared spectroscope （FTIR） for chemical structure and observation by atomic force microscopy （AFM） for surface morphology of SiO~ coatings demon- strated that both chemical compounds and surface feature of coatings have a remarkable influence on the coating barrier properties. It is noted that the processing parameters play a critical role in the barrier properties of coatings. After optimization of the SiOx coatings deposition conditions, i.e. the discharge power of 1500 W, 2 ： 1 of O2 ： HMDSO ratio and working pressure of 20 Pa, a better barrier property was achieved in this work.     

PEO-Like Functional Films＇ Polymerization in RF-PECVD

Polymer ethylene oxide （PEO） functional films can be used as a material for biocompatible research. In this paper, we investigated the structures of PEO-like films polymerized on Si surface with diethlyene glycole dimethyl ether （DEGDME） as the precursor and Ar as the dilution gas by plasma enhanced chemical vapor deposition （PECVD）. And the pulse plasma model was employed to polymerize the functional films. The chemical structure of the coatings was investigated by Fourier transform inference （FTIR） and X-ray photoelectron spectroscopy （XPS）. The results indicate that PEO-like structure films can be polymerized by DEGDME/Ar plasma. The concentration of C-O functional groups polymerized in the long plasma-off time was much higher than that in the short plasma-off time. With the same discharge parameters, moreover, the C-O ratio in polymers increased with a higher injected power.     

CrN films deposited by ion source-assisted magnetron sputtering

CrN coatings were deposited on Si(100) and piston rings by ion source assisted 40 kHz magnetron sputtering.Structure and composition of the coatings were characterized by X-ray diffraction,atomic force microscopy,scanning electron microscopy and transmission electron microscopy.Mechanical and tribological properties were assessed by microhardness and pin-on-disc testing.The ion source-assisted system has a deposition rate of 3.88 μm/h,against 2.2 μm/h without ion-source assistance.The CrN coatings prepared with ion source assistance exhibited an increase in microhardness(up to 16.3 GPa) and decrease in friction coefficient(down to 0.48) at the optimized cathode source-to-substrate distance.Under optimized conditions,CrN coatings were deposited on piston rings,with a thickness of 25 μm and hardness of 17.85 GPa.     

Plasma Modified Polypropylene Membranes as the Lithium-Ion Battery Separators

To reduce the thermal shrinkage of the polymeric separators and improve the safety of the Li-ion batteries,plasma treatment and plasma enhanced vapor chemical deposition（PECVD）of SiO_x-like are carried out on polypropylene（PP）separators,respectively.Critical parameters for separator properties,such as the thermal shrinkage rate,porosity,wettability,and mechanical strength,are evaluated on the plasma treated PP membranes.O₂ plasma treatment is found to remarkably improve the wettability,porosity and electrolyte uptake.PECVD SiO_x-like coatings are found to be able to effectively reduce the thermal shrinkage rate of the membranes and increase the ionic conductivity.The electrolyte-philicity of the Si Ox-like coating surface can be tuned by the varying O₂ content in the gas mixture during the deposition.Though still acceptable,the mechanical strength is reduced after PECVD,which is due to the plasma etching.     

The Gas Nucleation Process Study of Anatase TiO2 in Atmospheric Non-Thermal Plasma EnhancedChemical Vapor Deposition简

Abstract The gas phase nucleation process of anatase TiO2 in atmospheric non-thermal plasma enhanced chemical vapor deposition is studied. The particles synthesized in the plasma gas phase at different power density were collected outside of the reactor. The structure of the collected particles has been investigated by field scanning electron microscope （FESEM）, X-ray diffraction （XRD）, high resolution transmission electron microscopy （HRTEM） and selected area electron diffraction （SAED）. The analysis shows that uniform crystalline nuclei with average size of several nanometers have been formed in the scale of micro second through this reactive atmo- spheric plasma gas process. The crystallinity of the nanoparticles increases with power density. The high density of crystalline nanonuclei in the plasma gas phase and the low gas temperature are beneficial to the fast deposition of the 3D porous anatase TiO2 film.     

Infrared and Optical Properties of Amorphous Fluorinated Hydrocarbon Films Deposited with the Method of ECR Plasma

Using CH4 and CF4 precursor gases, amorphous fluorinated hydrocarbon (a-C:F:H) films were prepared with the method of microwave electronic cyclotron resonant (ECR) plasma chemical vapor deposition. Deposition rate of the film firstly increases and then decreases with variable flow ratios R {[CF4]/([CF4] + [CH4]} due to the competition between deposition and etching process. Results from Fourier-transform infrared transmission spectroscopy of these films show that C-F bond configuration in a-C:F:H films evolves with the variable gas flow ratios R. The locations of the C-F peaks in IR spectra shift to higher frequency with the increase of R, and finally the structure in films with R >75% takes on a PTFE-like structure, which mainly consists of -CF2- chain. The change of optical band gap Eg deduced by a Tauc plot with R is also discussed.     

PIC-EDDY Simulation of Different Impurities Deposition in Gaps of Carbon Tiles

A 3D Monte Carlo （MC） code PIC- EDDY, based on EDDY （erosion and deposition dynamic simulation） code, was used to investigate the redeposition of different impurities in the gaps of C tiles. By incorporating the rate coefficients of beryllium （Be） and tungsten （W） into the code, we obtain deposition profiles of hydrocarbon, beryllium and tungsten particles in the toroidal and poloidal gaps, respectively. The redeposition rate of tungsten was found to be higher than those of other impurities in the gaps, except at the bottom, due to its easier local deposition within one gyroradius. Due to the effect of reflection coefficients of hydrocarbon fragments on graphite, fewer hydrocarbons were resided at the entrance while more were deposited on the sides of the gap. At elevated plasma temperatures （such as 30 eV）, asymmetric deposition distributions were observed between the toroidal and poloidal gaps due to the dominant ionized particles. Ions were mainly deposited within 1 mm depth inside gaps, and the bottom deposition particles were almost all neutrals.     

Absorption of molecular forms of iodine from the gaseous phase by protective paint coatings

Conclusion Under the conditions of an accident, with molecular iodine present in the vapor-gas phase absorption of the molecular iodine by organosilicate coatings and especially by epoxy coatings can play a significant role in keeping the volatile forms of iodine in the containment vessel. At 90–100°C an OS-51-03 coating can absorb about 0.1 μg/cm² of molecular iodine and epoxy coatings, up to 3 μg/cm². The area of such coatings in the containment zone can run to tens of thousands of square meters, hence the coatings can absorb up to 550 g of iodine (in the case of coatings of three to five layers). Studies must be carried out, however, on the effect that the presence of water vapor, β and γ radiation, and aging of the coatings affect the efficiency of the absorption and containment of the molecular iodine. VNIPIéT. Translated from Atomnaya énergiya, Vol. 80, No. 6, pp. 442–446, June, 1996.     

Incorporation of Nitrogen into Amorphous Carbon Films Produced by Surface-Wave Plasma Chemical Vapor Deposition

In order to study the influence of nitrogen incorporated into amorphous carbon films, nitrogenated amorphous carbon films have been deposited by using surface wave plasma chemical vapor deposition under various ratios of N2/CH4 gas flow. Optical emission spectroscopy has been used to monitor plasma features near the deposition zone. After deposition, the samples are checked by Raman spectroscopy and x-ray photo spectroscopy (XPS). Optical emission intensities of CH and N atom in the plasma are found to be enhanced with the increase in the N2/CH4 gas flow ratio, and then reach their maximums when the N2/CH4 gas flow ratio is 5%. A contrary variation is found in Raman spectra of deposited films. The intensity ratio of the D band to the G band (ID/IG) and the peak positions of the G and D bands all reach their minimums when the N2/CH4 gas flow ratio is 5%. These show that the structure of amorphous carbon films has been significantly modified by introduction of nitrogen。     

A Polymeric/Inorganic Nanocomposite for Solid-State Dye-Sensitized Solar Cells

A novel nanocomposite consisting of poly （3, 4-ethylenedioxythiophene）/poly （styre-nesulfonate） （PEDOT/PSS） and CuI was synthesized via the reduction of CuCl2 by NaI in an aqueous PEDOT/PSS solution. The CuI in the composite was pure γ-phase, as was characterized by means of X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The dye-sensitized solar cell with PEDOT/PSS-CuI （15% in wt） nanocomposlte as hole-transport electrolyte exhibited a considerable photocurrent, photovoltage and energy conversion efficiency （i.e. Jsc = 0.50 mA·cm^-2, Voc = 0.44 V, η= 0.1%）.     

Comparison of the Free Volume of LiCl-Added SPPO Membrane and SPPO-PES Blend Membrane by Positron Annihilation Method

Positron annihilation lifetime spectroscopy （PALS） is a powerful technique for the study of free volume in polymers. The lifetime of ortho-positronium （o-Ps）, a bound state of an electron and a positron, can be used to assess the pore size, while the intensity can be used to characterize the number of pores. Based on the values of the long-lived o-Ps components in the lifetime spectra, the radii and fractional free volumes of sulfonated poly （2,6-dimethyl-1,4- phenyleneoxide） （SPPO） membranes with added LiCl and SPPO-PES （Polyethersulfone） blend were compared. Free volume radii in both kinds of membranes are discussed.     

Polymer Surface Treatment by Atmospheric Pressure Low Temperature Surface Discharge Plasma： Its Characteristics and Comparison with Low Pressure Oxygen Plasma Treatment

The polymer treatment with a low-temperature plasma jet generated on the atmospheric pressure surface discharge （SD） plasma is performed. The change of the surface property over time, in comparison with low pressure oxygen （O2） plasma treatment, is examined. As one compares the treatment by atmospheric pressure plasma to that by the low pressure O2 plasma of PS （polystyrene） the treatment effects were almost in complete agreement. However, when the atmospheric pressure plasma was used for PP（polypropylene）, it produced remarkable hydrophilic effects.     

Deposition of Polymer Thin Film Using an Atmospheric Pressure Micro-Plasma Driven by Dual-FrequencyExcitation简

Polymer thin film deposition using an atmospheric pressure micro-plasma jet driven by dual-frequency excitations is described in this paper. The discharge process was operated with a mixture of argon （6 slm） and a small amount of acetone （0-2100 ppm）. Plasma composition was measured by optical emission spectroscopy （OES）. In addition to a large number of Ar spectra lines, we observed some spectra of C, CN, CH and C2. Through changing acetone content mixed in argon, we found that the optimum discharge condition for deposition can be characterized by the maximum concentration of carbonaceous species. The deposited film was characterized by scanning electron microscopy （SEM） and X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared （FTIR） spectroscopy. The XPS indicated that the film was mostly composed of C with trace amount of O and N elements. The FTIR suggested different carbon-containing bonds （-CHx, C=O, C=C, C-O-C） presented in the deposited film.     

Development of Data Acquisition Card Driver for ICRH System on EAST

Presented in this paper is the development of the driver for the data acquisition card with a peripheral component interconnection （PCI） local bus on the ion cyclotron range of frequency heating （1CRH） system. The driver is mainly aimed at the embedded VxWorks system （real-time operating system） which is widely used in various fields of real-time systems. An efficient way is employed to develop this driver, which will advance the real-time control of the ICRH system on the experimental advanced superconductor tokamak （EAST）. The driver is designed using the TORNADO integrated development environment （IDE）, and implemented in C plus language. The details include the hardware configuration, analogue/digital （A/D） and digital/analogue （D/A） conversion, input and output （I/O） operation of the driver to support over five cards. The data acquisition card can be manipulated in a low-level program and meet the requirements of A/D conversion and D/A outputs.     

Role of Ion Beam Irradiation and Annealing Effect on the Deposition of AlON Nanolayers by Using Plasma Focus Device

AlON nanolayers are synthesized on Al substrate by the irradiation of energetic nitrogen ions using plasma focusing. Samples are exposed to multiple （5, 10, 15, 20 and 25） focus shots. Ion energy and ion number density range from 80 keV to 1.4 MeV and 5.6×10^19 m^- 3 to 1.3×10^19 m ^-3, respectively. Moreover, the effect of continuous annealing （473 K and 523 K） on an AlN surface layer synthesized with 25 focus shots is also examined. The main features of the X-ray diffraction （XRD） patterns with increasing focus shots are： （i） variation in the crystallinity of AlN along （111）, （200） and （311） planes, （ii） increasing average crystallite size of AlN （111） plane, and （iii） stress relaxation observed in AlN （111） and （200） planes. The crystallinity of AlN surface layer is comparatively better at 473 K annealing temperature. A broadened diffraction peak related to an aluminium oxide phase showing weak crystallinity is observed for 15 focus shots while non-bounded oxides are present in all other deposited layers. Raman and Fourier transform infrared spectroscopy （FTIR） analysis confirm the presence of AlN and Al203 for the surface layer annealed at 473 K temperature. Raman analysis shows that the overlapping of AlN and Al2Oa results in the development of residual stresses. Scanning electron microscope （SEM） results demonstrate that the formation of rounded grains （range from 20 nm to 200 nm） and variations in their microstructures features depend on the increasing number of focus shots. Decomposition of larger clusters into smaller ones is observed.     

Simultaneous Oxidization of NOx and SO2 by a New Non-thermal Plasma Reactor Enhanced by Catalyst and Additive

The non-thermal plasma as one of the most promising technologies for removing NOx and SO2 has attrm~ted much attention. In this study, a new plasma reactor combined with catalyst and additive was developed to effectively oxidize and remove NOx and SO2 in the flue gas. The experimental results showed that TiO2 could improve the oxidation efficiency of SO2 in the case of applying plasma while having a negative effect on the oxidation process of NO and NOx. With the addition of NH3, the oxidation rates of NOx, NO and SO2 were slightly increased. However, the effect of adding NH3 on NOx oxidation was negative when the temperature was above 200℃.     

Effect of Cold Plasma Treatment on Seed Germination and Growth of Wheat简

This study investigated the effect of cold helium plasma treatment on seed germina- tion, growth and yield of wheat. The effects of different power of cold plasma on the germination of treated wheat seeds were studied. We found that the treatment of 80 W could significantly improve seed germination potential （6.0%） and germination rate （6.7%） compared to the control group. Field experiments were carried out for wheat seeds treated with 80 W cold plasma. Com- pared with the control, plant height （20.3%）, root length （9.0%） and fresh weight （21.8%） were improved significantly at seedling stage. At booting stage, plant height, root length, fresh weight, stem diameter, leaf area and leaf thickness of the treated plant were respectively increased by 21.8%, 11.0%, 7.0%, 9.0%, 13.0% and 25.5%. At the same time, the chlorophyll content （9.8%）, nitrogen （10.0%） and moisture content （10.0%） were higher than those of the control, indicating that cold plasma treatment could promote the growth of wheat. The yield of treated wheat was 7.55 t-ha-1, 5.89% more than that of the control. Therefore, our results show that cold plasma has important application prospects for increasing wheat yield.     

Simulation of Electron-Beam Generating Plasma at Atmospheric Pressure

As electron-beam generating plasma is widely applied, the software tool EGS4 （Electron-Gamma Shower） was used to simulate the transmission and energy deposition of electron-beam in air. The simulation results indicated that the range of the electron-beam was inversely proportional to the gas pressure in a wide range of gas pressure, and the electron-beam of 200 keV could generate a plasma with a density 10^11 cm^-3 in air of latm. In addition, the energy distribution of the beam-electron and plasma density profile produced by the beam were achieved.     

Mechanical Properties of Thermoplastic Polyurethanes Laminated Glass Treated by Acid Etching Combined with Cold Plasma

To overcome the problem of interlaminar delamination of thermoplastic polyurethane laminated glass, silicate glass was etched with hydrofluoric acid and thermoplastic polyurethane was then treated with cold plasma. Compared with the untreated samples, the interlaminar shear strength of acid etching samples, cold plasma-treated samples and acid etching combined with cold plasma-treated samples increased by 97%, 84% and 341%, respectively. Acid etching combined with cold plasma-treated samples exhibited a higher flexural strength and strain as compared with the untreated samples. The impact energy of acid etching samples, cold plasmatreated samples and acid etching combined with cold plasma-treated samples increased by 8.7%, 8.1% and 11.6%, respectively, in comparison with the untreated samples. FT-IR analysis showed that a large number of -C-O, CO N and CO O C groups appeared on the surface of cold plasma-treated thermoplastic polyurethane, which resulted in the formation of hydrogen bonds. SEM results showed that some pittings formed on the surface of the silicate glass treated by acid etching, which resulted in the formation of a three-dimensional interface structure between tile silicate glass and polyurethane. Hydrogen bonds combined with the three-dimensional interface between silicate glass and polyurethanes co-improved the mechanical properties of thermoplastic polyurethanes laminated glass.     

Density and temperature of fermions and bosons from quantum fluctuations

A novel method to determine the density and temperature of a system constituted by fermions and/or bosons is proposed based on quantum fluctuations. For fermions system, the results in the limit where the reached temperature T is small and where there is no constraint for the reached temperature T compared to the Fermi energy ~f at a given density p are given, respectively. Quadrupole and multiplicity fluctuation relations are derived in terms of T/6f. We compared the two set results in the limit when Tis much smaller compared to Fermi energy Cf and they are consistent, as expected. The classical limit is also obtained for high temperatures and low densities. For bosons system, quadrupole and multiplicity fluctuations using Landau＇s theory of fluctuations near the critical point for a Bose-Einstein condensate （BEC） at a given density p are derived. As an example, we apply our approach to heavy ion collisions using the Constrained Molecular Dynamics model （CoMD） which includes the fermionic statistics. The multiplicity fluctuation quenching for fermions is found in the model and confirmed by experimental data. To reproduce the available experimental data better, we propose a modification of the collision term in the approach to include the possibility of ct-a collisions. The relevant Bose-Einstein factor in the collision term is properly taken into account. This approach increases the yields of bosons relative to fermions closer to data. Boson fluctuations become larger than one as expected.