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The Surface Photovoltage Mechanism of a Silicon Nanoporous Pillar Array

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Chinese Physics Letters 2013年第8期30卷 169-172页

作者： HU Zhen-Gang TIAN Yong-Tao li xin-jian Department of Physics and Laboratory of Material Physics Zhengzhou UniversityZhengzhou 450001

The surface photovoltage(SPV)mechanism of a silicon nanoporous pillar array(Si-NPA)is investigated by using SPV spectroscopy in different external electric *** comparisons with the SPV spectrum of single crystal silicon(sc-Si),the silicon nano-crystallite(nc-Si)/SiO_(x) nanostructure of Si-NPA is proved to be capable of producing obvious SPV in the wavelength range 300–580 *** SPV for the sc-Si layer and the nc-Si/SiO_(x) nanostructure has shown certain contrary characters in different external electric *** analysis,the localized states in the amorphous SiO_(x) matrix are believed to dominate the SPV for the nc-Si/SiO_(x) nanostructure.

关键词： crystallite producing contrary

The Surface Photovoltaic and Photoluminescent Evolution of a Silicon Nanoporous Pillar Array for Different Etching Times

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Chinese Physics Letters 2013年第6期30卷 201-204页

作者： HU Zhen-Gang TIAN Yong-Tao li xin-jian Department of Physics and Laboratory of Material Physics Zhengzhou UniversityZhengzhou 450001

A series of silicon nanoporous pillar array(Si-NPA)samples are prepared with different times of hydrothermal etching,and their surface morphologies are characterized.A systematic study on the evolution trend of the surface photovoltage and photoluminescence spectra discloses that the adoption of a prolonged etching time will increase the native degree of oxidation and decrease the interfacial states density localized in the SiO𝑥*** results might be helpful for designing Si-NPA-based semiconductor nanosystems with optimized physical properties.

关键词： interfacial designing Surface

The Effects of Solid Phase Additives on Sintering Properties of Alumina Bioceramic

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Journal of Wuhan University of Technology(Materials Science) 2003年第2期18卷 23-24页

作者：王欣宇 Wuhan University of Technology

In order to reduce the sintering temperature and improve the preparing conditions of alumina bioceramics,the Mg-Zr-Y composite solid phase additives were added into high purity Al 2O 3 micro-powder by chemical coprecipitation *** powder was shaped under 200MPa cold isostatic pressure,and then the biscuits were sintered at 1600℃ under normal *** sintered alumina materials were tested and the sintering mechanism was *** results show that physical properties of the material were improved *** Mg-Zr-Y composite solid additives could promote the sintering of alumina bioceramics and the mechanism is solid phase sintering.

关键词： alumina sintering additives property

Assessment of the hepatic microvascular changes in liver cirrhosis by perfusion computed tomography

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World Journal of Gastroenterology 2009年第28期15卷 3532-3537页

作者： Mai-lin Chen Qing-Yu Zeng jian-Wei Huo Xiao-Ming Yin Bao-Ping li jian-xin liu Department of Radiology ChinaMeitan General Hospital No. 29 Xibahe Nanli ChaoyangDistrict Beijing 100028 China

AIM： TO assess the hepatic microvascular parameters in patients with liver cirrhosis by perfusion computed tomography （CT）. METHODS： Perfusion CT was performed in 29 patients without liver disease （control subjects） and 39 patients with liver cirrhosis, including 22 patients with compensated cirrhosis and 17 patients with decompensated cirrhosis, proved by clinical and laboratory parameters. CT cine-scans were obtained over 50 s beginning with the injection of 50 mL of contrast agent. Hepatic microvascular parameters, mean transit time （MTT） and permeability surface area product （PS） were obtained with the Perfusion 3 software （General Electric, ADW 4.2）. RESULTS： The overall differences of MTT and PS between control subjects, patients with compensated cirrhosis and those with decompensated cirrhosis were statistically significant （P = 0.010 and P = 0.002, respectively）. MTT values were 15.613 ± 4.1746 s, 12.592 ± 4.7518 s, and 11.721 ± 4.5681 s for the three groups, respectively, while PS were 18.945 ± 7.2347 mL/min per 100 mL, 22.767 ± 8.3936 mL/min per 100 mL, and 28.735 ± 13.0654 mL/min per 100 mL. MTT in decompensated cirrhotic patients were significantly decreased compared to controls （P = 0.017）, whereas PS values were remarkably increased （P = 0.001）.CONCLUSION： The hepatic microvascular changes in patients with liver cirrhosis can be quantitatively assessed by perfusion CT. Hepatic microvascular parameters （MTr and PS）, as measured by perfusion CT, were significantly altered in decompensated cirrhosis.

关键词： Tomography X-ray computed Hepaticmicrocirculation Cirrhosis

Selective Reduction of 7-Demethylsinomenine

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Chemical Research in Chinese Universities 2008年第5期24卷 557-560页

作者： li Yu-feng BU Qing-min QIAN Yi PAN Yi li jian-xin HUANG Le-qun ZHU Hong-jun School of Science Nanjing University of Technology Nanjing 210009 P. R. China Department of Chemistry School of Chemistry and Chemical Engineering School of Medicine Nanjing University Nanjing 210093 P. R. China

Several borohydride reagents： sodium borohydride, sodium cyanoborohydride, soudium acetoxyborohydride and soudium triacetoxyborohydride were screened, respectively, for the reduction of 7-demethylsinomenine, which was an α,β-dicarbonyl compound derived from sinomenine. Highly regio-and stereo-selectivity was acquired when sodium cyanoborohydride or NaBH（OAc）3 was used. The product was structurally confirmed as 7R configuration by NMR, X-ray crystal diffraction analysis. Some preliminary discussion was also made on the mechanism of the selective reduction.

关键词： 7-Demethylsinomenine Regioselective reduction Stereoselective reduction Borohydride reagents

A New Idea and Technique of Fiber Gratings and Photodetectors in Broad-band Fiber Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2001年第3期8卷 79-80页

作者： li jian-xin directed by REN Xiao-ming

Contents of this thesis are supported by the National Natural Foudation of China under Contract No.69625101, and the item is named “Tunable Optical Technology in Wavelength Division Multiplexing (WDM)” and is under charge of Professor Ren Xiaomin. They are also supported by subject 307 in National Program “863”: i.e., RCE photodetectors (PDs) used in Wavelength Division Multiplexing. Fiber Bragg Gratings (FBGs) have emerged as important optical fiber passive components in a variety of light-wave applications. It is expected that FBGs will play a key role in the next generation of optical fiber communication systems and sensor fileds. Most of these applications are based on the narrow-band reflection of FBGs. In this thesis, transmission dispersion, nonlinearity and tunability of FBGs are studied. The main contents are as follows: Transmission dispersion of FBGs is studied and the capability of dispersion compensation of FBGs is calculated theoretically. In the experiments, the dispersions of 10 Gb/s at 11.1 km and 22.22 km are compensated successfully by an unchirped fiber grating for the first time in China and the tunable compensation is achieved for the first time internationally. The scheme of tunable dispersion compensation using cascaded fiber gratings in WDM is analyzed and designed. It is indicated that the dispersion compensation in transmission using uniform fiber gratings is a better and more effective compensation scheme compared with the tradifitonal dispersion compensation using chirped fiber gratings. It is originally proposed that people can simulate characteristics of a long distance optical fiber by a short uniform fiber grating. This is verified for the first time experimentally. In the experiment, a short grating (about 1 cm) operated in transmission is used to simulate pulse broadening of 11.1 km optical fiber. This method can be used to detect performance of long distance transmission of communication systems. It is originally proposed that peo

关键词： wavelength division multiplexing fiber Bragg grating transmission dispersion dispersion compensation

High Prevalence and Factors Contributing to Hyperhomocysteinemia, Folate Deficiency, and Vitamin B_(12) Deficiency among Healthy Adults in Shanghai, China

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Biomedical and Environmental Sciences 2019年第1期32卷 63-67页

作者： WANG Yu Heng YAN Qing Hua XU Ji Ying li xin jian CHENG Min Na Shanghai Municipal Center for Disease Control and Prevention

Elevated plasma or serum total homocysteine (tHcy) level has been established as a risk factor for cardiovascular disease[1], as well as dementia and cognitive decline[2]. Plasma or serum folate and vitamin B12 influence homocysteine (Hcy) metabolism as a co-substrate and cofactor respectively, so that low concentrations of folate and vitamin B12 are also associated with high Hcy levels[1]. However, not much information is available describing serum tHcy, folate, and vitamin B12 status in Shanghai adults, especially in a healthy population. Therefore, we hypothesize that low serum folate and vitamin B12 is associated with high Hcy in healthy adults in Shanghai. The aim of this study was to determine the status of serum tHcy, folate, and vitamin B12, and the prevalence and factors contributing to HHcy, folate deficiency, and vitamin B12 deficiency among healthy adults in Shanghai, China.

关键词： Cardiovascular disease Serum total homocysteine (tHcy) Vitamin B12

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自旋涨落与非常规超导配对

物理学报 2021年第1期70卷 11-28页

作者：李建新南京大学物理学院固体微结构物理国家重点实验室南京210093 南京大学人工微结构科学与技术协同创新中心南京210093

铜氧化物高温超导、铁基高温超导、重费米子超导和k-型层状有机超导等超导体的超导态都与磁性有序态相邻,且超导能隙在动量空间一般存在变号.因此,这些超导体的超导机理被认为有别于常规BCS超导中的电子交换声子导致的各向同性s-波配对... 详细信息

铜氧化物高温超导、铁基高温超导、重费米子超导和k-型层状有机超导等超导体的超导态都与磁性有序态相邻,且超导能隙在动量空间一般存在变号.因此,这些超导体的超导机理被认为有别于常规BCS超导中的电子交换声子导致的各向同性s-波配对.在这些非常规超导中,自旋涨落被认为是导致电子形成库珀对的主要起源之一.本文主要以铜基和铁基高温超导为例简要综述非常规超导中的自旋序和自旋涨落性质,二维哈伯徳模型中超导的起因及在解释铜基和铁基高温超导配对对称性的应用,以及与非常规超导紧密相关的中子自旋共振模性质和理论解释.我们认为,尽管磁性和超导性的相互影响已经过多年研究,但仍是当前一个富有挑战的活跃研究领域.

关键词：非常规超导自旋激发超导配对对称性自旋共振模

Relationship between HBV genotypes and anti-viral therapeutic efficacy of interferon-alpha

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Hepatobiliary & Pancreatic Diseases International 2007年第2期6卷 166-171页

作者： Ma, Jin-Chun Wang, Lu-Wen li, xin-jian liao, Yong-Feng Hu, Xi-Ya Gong, Zuo-Jiong Wuhan Univ Renmin Hosp Dept Infect Dis State Key Lab Virol Wuhan 430060 Peoples R China Huangshi Aikang Hosp Dept Infect Dis Huangshi 435000 Peoples R China

BACKGROUND: Much evidence demonstrates that the genotypes of hepatitis B virus (HBV) present differences in pathogenicity and outcomes owing to differences in genetic structure. This study aimed to investigate the influences of HBV genotypes on the anti-viral therapeutic efficacy of interferon-alpha (IFN-alpha) in chronic hepatitis B patients, and to determine the relationship between HBV genotypes and levels of viral replication or gene variations. METHODS: The chronic hepatitis B patients who were treated with IFN-alpha were selected randomly. Anti-viral therapeutic efficacy was monitored in these patients. The HBV genotypes were detected by PCR microplate hybridization EliSA. The levels of serum HBV-DNA were determined by fluorescence quantitative PCR. HBV gene variation at pre-C and basic core promoter (BCP) regions were assayed by gene chip technology. RESULTS: Genotypes B and C were predominant in 94 chronic hepatitis B patients. A, E and F genotypes were not found in these patients. The HBV-DNA levels of genotype C and mixed genotypes were significantly higher than those of genotype B. The response to IFN-alpha in patients with genotype B was markedly better than in those with genotypes C and D, and the complete response to IFN-alpha was only observed in genotype B. The response to IFN-alpha in patients with mixed genotypes was the least sensitive. The negative transition of HBeAg was correlated with variations in the HBV pre-C and BCP regions in patients with partial or no response to IFN-alpha. The variation rates of HBV pre-C and BCP regions were clearly higher in genotype C than in genotype B. CONCLUSIONS: The results suggest that HBV genotype is correlated with the serum levels of HBV-DNA, HBV gene variations and therapeutic efficacy of IFN-alpha. The regular detection of HBV genotypes in the clinic will be of benefit for disease prognosis and planning of anti-viral therapeutic strategies.

关键词： hepatitis B virus genotype gene variation interferon-alpha anti-viral therapy