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Journal of Semiconductors 2011年第9期32卷 147-150页

作者：武春波周玉琴李国荣刘丰珍 graduate University of the chinese academy of sciences

Amorphous/crystalline silicon heterojunctions（a-Si：H/c-Si SHJ） were prepared by plasma-enhanced chemical vapor deposition（PECVD）.The influence of the initial transient state of the plasma and the hydrogen pre-treatment on the interfacial properties of the heteroj unctions was *** results indicate that：（1） The instability of plasma in the initial stage will damage the surface of *** a shutter to shield the substrate for 100 s from the starting discharge can prevent the influence of the instable plasma process on the Si surface and also the interface between a-Si and c-Si.（2） The effect of hydrogen pre-treatment on interfacial passivation is constrained by the extent of hydrogen plasma bombardment and the optimal time for hydrogen pre-treatment is about 60 s.

关键词： silicon heterojunction PECVD interface properties initial transient state of plasma hydrogen plasma pre-treatment

Progress on the Lanzhou Penning Trap

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Plasma Science and Technology 2012年第5期14卷 421-423页

作者：黄文学田玉林王玥王均英朱志超孙宇梁吴巍何源马力祯徐瑚珊肖国青 Institute of Modern Physics Chinese Academy of Sciences graduate University of chinese academy of sciences

The Penning trap is one of the most important experimental devices in the field of nuclear physics, and measures atomic masses with the highest precision in the world. Many such devices are currently in operation, with more being designed and constructed. To start the experimental study of atomic masses with very high precision in China, the Lanzhou Penning Trap (LPT) is being constructed at the Institute of Modern Physics, chinese academy of sciences. In this paper the progress and status of the LPT will be reported.

关键词： Penning trap mass spectrometry LPT superconducting magnet

Modification of Optical Band-Gap of Si Films After Ion Irradiation

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Plasma Science and Technology 2012年第7期14卷 632-635页

作者：朱亚滨王志光孙建荣姚存峰魏孔芳缑洁马艺准申铁龙庞立龙盛彦斌 Institute of Modern Physics Chinese Academy of Sciences graduate university of chinese academy of sciences

Amorphous silicon （a-Si）, nanocrystalline silicon （nc-Si） and hydrogenated nanocrys- talline silicon （nc-Si：H） films were fabricated by using chemical vapor deposition （CVD） system. The a-Si and nc-Si thin films were irradiated with 94 MeV Xe-ions at fluences of 1.0 × 10^11 ions/cm2, 1.0 × 10^12 ions/cm^2 and 1.0 × 10^13 ions/era2 at room temperature （RT）. The nc-Si：H films were irradiated with 9 MeV Xe-ions at 1.0 ×10^12 Xe/cm^2, 1.0 × 10^13 Xe/cm2 and 1.0×10^14 Xe/cm2 at RT. For comparison, mono-crystalline silicon （c-Si） samples were also irradiated at RT with 94 MeV Xe-ions. All samples were analyzed by using an UV/VIS/NIR spectrometer and an X-ray powder diffractometer. Variations of the optical band-gap （Eg） and grain size （D） versus the irradiation fluence were investigated systematically. The obtained results showed that the optical band-gaps and grain size of the thin films changed dramatically whereas no observable change was found in c-Si samples after Xe-ion irradiation. Possible mechanism underlying the modification of silicon thin films was briefly discussed.

关键词： ion irradiation silicon film optical band-gap grain size

50GeSe_2-25In_2Se_3-25CsI glass doped with Tm^(3+),Tm^(3+)/Ho^(3+) and Tm^(3+)/Er^(3+) foramplifiers working at 1.22 μm

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Journal of Rare Earths 2011年第10期29卷 920-923页

作者：熊慧华唐高罗澜陈玮 Shanghai Institute of Ceramics Chinese Academy of Sciences graduate School of chinese academy of sciences

Se-based chalcohalide glass of 50GeSe2-25In2Se3-25CsI was prepared. The thermal and optical characterizations revealed that this host was thermally and optically superior for practical applications. Strong emission centered at 1.22μm was observed in all Tm3＋ sin- gle-doped, Tm3＋/Ho3＋ and Tm3＋/Er3＋ co-doped samples with an excitation of 808 nm wavelength. The emission was attributed to the Tm3＋： 3Hs-→3H6 transition. The co-doping of Ho3＋ or Er3＋ largely broadened the width and slightly strengthened the intensity of the 1.22 gm emis- sion. The possible energy transfer processes and luminescence kinetics were figured. In addition, its potential application as the host material for novel optical amplifiers was discussed.

关键词： rare earths chalcohalide glass co-dope emission amplifier

Electrical properties and microstructural characterization of Ni/Ta contacts to n-type 6H–SiC

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chinese Physics B 2015年第12期24卷 465-469页

作者：周天宇刘学超黄维卓世异郑燕青施尔畏 Shanghai Institute of Ceramics Chinese Academy of Sciences graduate University of chinese academy of sciences

A Ni/Ta bilayer is deposited on n-type 6H–SiC and then annealed at different temperatures to form an ohmic contact. The electrical properties are characterized by I–V curve measurement and the specific contact resistance is extracted by the transmission line method. The phase formation and microstructure of the Ni/Ta bilayer are studied after thermal annealing. The crystalline and microstructure properties are analyzed by using glance incident x-ray diffraction（GIXRD）,Raman spectroscopy, and transmission electron microscopy. It is found that the transformation from the Schottky to the Ohmic occurs at 1050℃ and the GIXRD results show a distinct phase change from Ta2C to TaC at this temperature. A specific contact resistance of 6.5×10^-5Ω·cm^2is obtained for sample Ni（80 nm）/Ta（20 nm）/6H–SiC after being annealed at 1050℃. The formation of the TaC phase is regarded as the main reason for the excellent Ohmic properties of the Ni/Ta contacts to 6H–Si C. Raman and TEM data reveal that the graphite carbon is drastically consumed by the Ta element, which can improve the contact thermal stability. A schematic diagram is proposed to illustrate the microstructural changes of Ni/Ta/6H–SiC when annealed at different temperatures.

关键词： SiC Ohmic contact Ni/Ta

Association between Alcohol, Smoking and HLA-DQA1*0201 Genotype in Psoriasis

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 597-602页

作者： Guang-Yong ZHENG1,2#, Sheng-Cai WEI3#, Tie-Liu SHI1, and Yi-Xue LI1* 1Bioinformatics Center, Shanghai Institutes for Biological sciences, chinese academy of sciences, graduate School of the chinese academy of sciences, Shanghai 200031, China Research Center for Proteome Analysis, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences, graduate School of the chinese academy of sciences, Shanghai 200031, China 3Guangzhou Institute of Dermatology, Guangzhou 510095, China Bioinformatics Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

Psoriasis is a chronic skin disease triggered by genetic, environment or other risk factors such as infection, drugs, stress, moisture, alcohol, and smoking. A major psoriasis susceptibility locus at 6p21.3 has been identified. Further studies found that HLA-DQA1*0201 allele was associated with psoriasis. However, there were few data exploring an association between the environmental factors and susceptibility genes. In this study, the samples of 189 patients with psoriasis and 333 healthy controls were collected with their consent and were carried on analysis through polymerase chain reaction sequence-specific primer (PCR- SSP) method. The proportion of male psoriasis patients engaging in the smoking and alcohol was much higher than that of the control group (P6.91, P<1.0×10–4).

关键词： psoriasis HLA-DQA1*0201 allele smoking alcohol association

Design and analysis of a UWB low-noise amplifier in the 0.18μm CMOS process

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Journal of Semiconductors 2009年第1期30卷 39-43页

作者：杨袆高茁杨丽琼黄令仪胡伟武 Institute of Computing Technology Chinese Academy of Sciences graduate University of the chinese academy of sciences

An ultra-wideband （3.1-10.6 GHz） low-noise amplifier using the 0.18μm CMOS process is presented. It employs a wideband filter for impedance matching. The current-reused technique is adopted to lower the power consumption. The noise contributions of the second-order and third-order Chebyshev fliers for input matching are analyzed and compared in detail. The measured power gain is 12.4-14.5 dB within the bandwidth. NF ranged from 4.2 to 5.4 dB in 3.1-10.6 GHz. Good input matching is achieved over the entire bandwidth. The test chip consumes 9 mW （without output buffer for measurement） with a 1.8 V power supply and occupies 0.88 mm^2.

关键词： ultra-wideband low-noise amplifier CMOS

A 270-MHz to 1.5-GHz CMOS PLL clock generator with reconfigurable multi-functions for FPGA

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Journal of Semiconductors 2011年第4期32卷 149-154页

作者：张辉杨海钢王瑜刘飞高同强 Institute of Electronics Chinese Academy of Sciences graduate University of the chinese academy of sciences Institute of Electronics Chinese Academy of SciencesBeijing 100190China

A PLL clock generator with reconfigurable multi-functions for FPGA design applications is presented. This clock generator has two configurable operation modes to achieve clock multiplication and phase alignment functions,*** output clock signal has advanced clock shift ability such that the phase shift and duty cycle are *** order to further improve the accuracy of phase alignment and phase shift,a VCO design based on a novel quick start-up technique is proposed.A new delay partition method is also adopted to improve the speed of the post-scale counter,which is used to realize the programmable phase shift and duty cycle.A prototype chip implemented in a 0.13-μm CMOS process achieves a wide tuning range from 270 MHz to 1.5 *** power consumption and the measured RMS jitter at 1 GHz are less than 18 mW and 9 ps,*** settling time is approximately 2μs.

关键词： PLL clock generator reconfigurable VCO

The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期 39-88页

作者： Feimin Huang Weiqiang Wang Yong Wang Feng Xiao academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical sciences University of Chinese Academy of Sciences Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and StatisticsHunan Normal University

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L2-L∞framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

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Environmental contamination and health hazard of lead and cadmium around Chatian mercury mining deposit in western Hunan Province,China

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Transactions of Nonferrous Metals Society of China 2010年第2期20卷 308-314页

作者：孙宏飞李永华姬艳芳杨林生王五一李海蓉 Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences graduate School of chinese academy of sciences

A field survey concerning lead and cadmium pollution in environment mediums and hair samples around the Chatian mercury mining deposit in western Hunan Province,China,was conducted to preliminarily evaluate their health hazard to local *** results show that mining wastes,especially tailing,contain high cadmium level with the maximum of 79.92μg/g. High levels of lead and cadmium are accumulated in surface water and paddy soil,respectively,and both metals pollution occurs in brown *** average daily intake dose(ADD)of lead for local adults via three routes reaches up to 7.7μg/(kg·d),exceeding the provision tolerable daily intake by JECFA of 3.5μg/(kg·d),and drinking water exposure route contributes the highest daily *** an indicator for heavy metal exposure,the hair of local population contains Pb(5.06±3.02)μg/*** average daily intake dose of cadmium for adults is 0.119μg/(kg·d).More attention must be paid on health risk from lead pollution compared with cadmium.

关键词： average daily intake dose cadmium lead mercury mine area