Recent progress on non-thermal plasma technology for high barrier layer fabrication

This review describes the application of non-thermal plasma（NTP） technology for high barrier layer fabrication in packaging area.NTP technology is considered to be the most prospective approaches for the barrier layer fabrication over the past decades due to unpollution,high speed,low-costing.The applications of NTP technology have achieved numerous exciting results in high barrier packaging area.Now it seemly demands a detailed review to summarize the past works and direct the future developments.This review focuses on the different NTP resources applied in the high barrier area,the role of plasma surface modification on packaging film surface properties,and the deposition of different barrier coatings based on NTP technology.In particular,this review emphasizes the cutting-edge technologies of NTP on interlayer deposition with organic,inorganic for multilayer barriers fabrication.The future prospects of NTP technology in high barrier film areas are also described.

Characteristics of inductively coupled plasma(ICP)and helicon plasma in a single-loop antenna

Large area uniform plasma sources,such as high-density magnetized inductively coupled plasma(ICP)and helicon plasma,have broad applications in industry.A comprehensive comparison of ICP and helicon plasma,excited by a single-loop antenna,is presented in this paper from the perspectives of mode transition,hysteresis behavior,and density distribution.The E-H mode transition in ICP and the E-H-W mode transition in helicon plasma are clearly observed in the experiments.Besides,the considerable variation of hysteresis behavior from inverse hysteresis to normal hysteresis by the influence of the magnetic field is explored.The bi-Maxwellian and Maxwellian electron energy distribution functions in each discharge are used to explain this phenomenon,which is essentially related to the transition from a nonlocal kinetic property to a local kinetic property of electrons.In addition,we notice that the plasma density,in the radial direction,is peaked in the center of the tube in ICP,but a complicated distribution is formed in helicon plasma.In the axial direction,the maximum plasma density is still in the center of the antenna in ICP,whereas the highest plasma density is located downstream,far away from the antenna,in helicon plasma.It is believed that the reflected electrons in the sheath and pre-sheath by the upper metallic endplate and downstream propagated helicon wave will be responsible for this plasma density profile in helicon plasma.Due to the constrained electron motion in the magnetic field,an extremely uniform density distribution will be obtained with an appropriate axial magnetic field in the wave discharge mode.

The low temperature growth of stable p-type ZnO films in HiPIMS

In this study,the influence of substrate temperature on properties of Al-N co-doped p-type ZnO films is explored.Benefitting from the high ionization rate in high-power impulsed magnetron sputtering,the concentration of ionized nitrogen N+and ionized zinc Zn+were increased,which promoted the formation of ZnO films and lowered the necessary substrate temperature.After optimization,a co-doped p-type ZnO thin film with a resistivity lower than 0.35Ωcm and a hole concentration higher than 5.34×10^(18)cm^(-3)is grown at 280°C.X-ray diffraction results confirm that Al-N co-doping does not destruct the ZnO wurtzite structure.X-ray photoelectron spectroscopy demonstrates that the presence of Al promotes the formation of acceptor(No)defects in ZnO films,and ensures the role of Al in stabilizing p-type ZnO.

等离子体放电催化处理污染水的研究进展

等离体子体处理废液技术具有处理范围广、快速、高效、无二次污染等优点,在工业界得到广泛的应用。在等离子体处理技术的应用领域,针对相对成本高这一限制,选择合适的催化剂与低温等离子体结合可以降低成本,是比较有发展前景的技术。等离子体协同催化技术可以在充分利用等离体子激发产生的物理和化学效应的同时,利用催化剂有效降低活化能,既提高污染物的降解效率,又提高了等离子体的能量利用率。本文就等离子体同催化剂的协同效应对污染物的降解进展进行了分析,从等离子体的类型、反应器、催化的种类、降解的机理以及对污染物降解效率的评估等这几个方面进行了阐述。文章对未来的研究趋势提出展望,为研究者在理论研究基础上尽早实现等离子体和催化剂处理污水技术的实际工业化提供技术支持。

Fabrication and characterization of iron and iron carbide thin films by plasma enhanced pulsed chemical vapor deposition

A new pulsed chemical vapor deposition（PCVD） process has been developed to fabricate iron（Fe） and iron carbide(Fe1-xCx) thin films at low temperature range from 150 ℃ to 230 ℃.The process employs bis（1,4-di-tert-butyl-1,3-diazabutadienyl）iron（Ⅱ） as iron source and hydrogen gas or hydrogen plasma as the coreactant.The films deposited with hydrogen gas are demonstrated polycrystalline with body-centered cubic Fe.However,for the films deposited with hydrogen plasma,the amorphous phase of iron carbide is obtained.The influence of the deposition temperature on iron and iron carbide characteristics have been investigated.

Insight into the remaining high surface energy of atmospheric DBD plasma-treated polyethylene web after three months' aging

In this paper, we report the modification of polyethylene(45 μm in thickness) webs through a roll-to-roll dielectric barrier discharge plasma treatment in an open atmospheric environment.Our work differs from the normal adopted corona discharge treatment at an atmospheric pressure, in that three monomers: allylamine, acrylic acid, and ethanol, are inlet into the discharge zone by argon(Ar) carrier gas. As a comparison, Ar plasma treatment is also carried out. We focus on the aging properties of treated plastics in the open air. It is found that the modified webs can retain the surface energy as high as 50.0?±?1 mN m^(-1) for more than three months. After characterization of the as-prepared and aged samples by the surface roughness, the wettability, and the chemical structure, the mechanism of retaining high surface energy is then presumed. We think that the initial high surface energy just after plasma treatment is correlated to the grafted functional groups, while the over 50.0 mN m^(-1) remaining surface energy after three month aging is due to the stable concentrations of oxygen-contained and nitrogencontained groups by post-reaction on the surfaces.

High power impulse magnetron sputtering and its applications

High power impulse magnetron sputtering（HiPIMS） has attracted a great deal of attention because the sputtered material is highly ionized during the coating process,which has been demonstrated to be advantageous for better quality coating.Therefore,the mechanism of the HiPIMS technique has recently been investigated.In this paper,the current knowledge of HiPIMS is described.We focus on the mechanical properties of the deposited thin film in the latest applications,including hard coatings,adhesion enhancement,tribological performance,and corrosion protection layers.A description of the electrical,optical,photocatalytic,and functional coating applications are presented.The prospects for HiPIMS are also discussed in this work.

Amplitude of peroneal compound motor action potential increases in type 2 diabetes with thyroid autoimmunity

Dear Editor, Diabetic peripheral neuropathy （DPN） is a frequently oc-curring complication of diabetes. DPN is diagnosed on the basis of findings of neural electrophysiological study, such as the nerve conduction study （NCS）. The most common NCS manifestations of DPN include slow velocity, prolonged la-tency, and decreased amplitude. Risk factors for DPN in-elude age, hyperglycemia, dyslipidemia, smoking, atherosclerotic cardiovascular disease, peripheral arterial disease, diabetic nephropathy, and diabetic retinopathy.