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Silicon-on-Insulator Structure Fabricated by Electron Beam Evaporation of Si on Porous Si and Epitaxial Layer Transfer

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Chinese Physics Letters 2001年第5期18卷 662-664页

作者： LIU Wei-Li duo xin-zhong WANG Lian-Wei ZHANG Miao SHEN Qin-Wo LIN Cheng-Lu Paul K.Chu State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 Department of Physics and Materials Science City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong

Epitaxial monocrystalline Si was grown on porous silicon by ultra-high vacuum electron beam *** of reflection high energy electron diffraction,atomic force microscopy,cross-section transmission electron microscopy and Rutherford backscattering spectrometry and channeling(RBS/C)show a good quality of the epitaxial ***,silicon-on-insulator materials were successfully produced by bond and etch back of porous *** quality of the silicon on insulator samples was investigated by RBS/C and spreading resistance *** results show that both the crystalline quality and electrical quality are *** addition,the interface between the top Si layer and SiO2 buried layer is very sharp.

关键词： Epitaxial porous Electron

一种具有新型增益控制技术的CMOS宽带可变增益LNA

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电子与信息学报 2010年第11期32卷 2772-2775页

作者：谌斐华多新中孙晓玮中国科学院上海微系统与信息技术研究所上海200050 中国科学院研究生院北京100039 中芯国际集成电路制造(上海)有限公司上海201203

高速超宽带无线通信的多标准融合是未来射频器件的发展趋势,该文提出一种基于CMOS工艺、具有新型增益控制技术的宽带低噪声放大器(LNA),采用并联电阻反馈实现宽带输入匹配,并引入噪声消除技术来减小噪声以提高低噪声性能;输出带有新型6... 详细信息

高速超宽带无线通信的多标准融合是未来射频器件的发展趋势,该文提出一种基于CMOS工艺、具有新型增益控制技术的宽带低噪声放大器(LNA),采用并联电阻反馈实现宽带输入匹配,并引入噪声消除技术来减小噪声以提高低噪声性能;输出带有新型6位数字可编程增益控制电路以实现可变增益。采用中芯国际0.13μm RF CMOS工艺流片,芯片面积为0.76mm2。测试结果表明LNA工作频段为1.1-1.8GHz,最大增益为21.8dB、最小增益8.2dB,共7种增益模式。最小噪声系数为2.7dB,典型的IIP3为-7dBm。

关键词： RFCMOS 低噪声放大器(LNA) 噪声消除宽带可变增益

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新型溶胶-凝胶法制备纳米MgO薄膜的研究

无机材料学报 1999年第5期14卷 828-832页

作者：符晓荣宋志棠多新中林成鲁武光明中国科学院上海冶金所信息功能材料国家重点实验室上海200050 北京石油化工学院基础部北京102600

以硝酸镁为起始原料，胶棉液为添加剂，在Ｓｉ（１００）衬底上成功地制备ＭｇＯ薄膜，结果表明，胶棉液是形成ＭｇＯ溶胶的关键组份；薄膜的晶体结构与胶棉液的含量及退火温度有关．同时，用Ｘ射线衍射（ＸＲＤ）、原子力显微镜（ＡＦ... 详细信息

以硝酸镁为起始原料，胶棉液为添加剂，在Ｓｉ（１００）衬底上成功地制备ＭｇＯ薄膜，结果表明，胶棉液是形成ＭｇＯ溶胶的关键组份；薄膜的晶体结构与胶棉液的含量及退火温度有关．同时，用Ｘ射线衍射（ＸＲＤ）、原子力显微镜（ＡＦＭ）和透射电镜（ＴＥＭ）对薄膜的微观结构进行了分析．

关键词：薄膜溶胶凝胶法纳米级氧化镁薄膜

Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study

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World Journal of Gastroenterology 2025年第2期31卷 85-101页

作者： Jun-Yi Zhan Jie Chen Jin-zhong Yu Fei-Peng Xu Fei-Fei xing De-xin Wang Ming-Yan Yang Feng xing Jian Wang Yong-Ping Mu Cell Biology Laboratory Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute of Liver Diseases Shanghai Academy of Chinese MedicineShanghai 201203China Clinical Key Laboratory of Traditional Chinese Medicine of Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Key Laboratory of Liver and Kidney Disease of the Ministry of Education Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Gastroenterology and Hepatology Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Institute of Liver Disease Fudan UniversityShanghai 200032China Evidence-Based Medicine Center Fudan UniversityShanghai 200032China Department of Gastrointestinal Endoscopy Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Hepatology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and *** its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are *** To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal *** This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 *** least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic *** validation was performed with bootstrap *** assessed the discrimination,calibration and accuracy of the model,and performed patient risk *** Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)*** predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation ***,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both *** We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients.

关键词： Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis

Optical Interference Effects by Metal Cathode in Organic Light-Emitting Diodes

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Chinese Physics Letters 2004年第7期21卷 1370-1373页

作者： WUZhao-xin WANGLi-duo QIUYong KeyLabofOrganicOptoelectronics&MolecularEngineering DepartmentofChemistryTsinghuaUniversityBeijing100084

The dependence of light intensities of organic light-emitting diodes (OLEDs) on the distance of emission zone to metal cathode is investigated numerically. The investigation is based on the half-space optical model that accounts for optical interference effects of metal cathode. We find that light intensities of OLEDs are functions of the distance of emission zone from the metal cathode because of the effect of interference of the metal cathode. This interference leads to an optimal location of emission zone in OLEDs for the maximum of light intensities. Optimal locations of emission zone are numerically shown in various emitting colour OLEDs with different metal cathodes and these results are expected to give insight into the preparation of high efficiency full colour or white light OLEDs.

关键词： Condensed matter: electrical magnetic and optical Electronics and devices Optics quantum optics and lasers

Dynamics of Soil Organic Carbon Under Uncertain Climate Change and Elevated Atmospheric CO_2

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Pedosphere 2012年第4期22卷 489-496页

作者： LIN zhong-Bing ZHANG Ren-duo Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275(China)

Climate change and elevated atmospheric CO2 should affect the dynamics of soil organic carbon （SOC）. SOC dynamics under uncertain patterns of climate warming and elevated atmospheric CO2 as well as with different soil erosion extents at Nelson Farm during 1998-100 were simulated using stochastic modelling. Results based on numerous simulations showed that SOC decreased with elevated atmospheric temperature but increased with atmospheric CO2 concentration. Therefore, there was a counteract effect on SOC dynamics between climate warming and elevated CO2. For different soil erosion extents, warming 1℃ and elevated atmospheric CO2 resulted in SOC increase at least 15%, while warming 5 ℃ and elevated CO2 resulted in SOC decrease more than 29%. SOC predictions with uncertainty assessment were conducted for different scenarios of soil erosion, climate change, and elevated CO2. Statistically, SOC decreased linearly with the probability. SOC also decreased with time and the degree of soil erosion. For example, in 2100 with a probability of 50%, SOC was 1 617, 1 167, and 892 g m^-2, respectively, for no, minimum, and maximum soil erosion. Under climate warming 5 ℃ and elevated CO2, the soil carbon pools became a carbon source to the atmosphere （P 〉 95%）. The results suggested that stochastic modelling could be a useful tool to predict future SOC dynamics under uncertain climate change and elevated CO2.

关键词： atmospheric carbon dioxide climate warming soil carbon pools soil erosion stochastic modelling

Practical Polar Code Construction For Degraded Multiple-Relay Networks

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China Communications 2017年第4期14卷 127-139页

作者： Bin duo Xiaoling zhong Yong Guo College of Information Science & Technology Chengdu University of Technology

In this paper, based on the characteristics of polar codes, a new decode-and-forward strategy called generalized partial information relaying protocol is proposed for degraded multiple-relay networks with orthogonal receiver components(MRNORCs). In such a protocol, with the help of partial information from previous nodes, each relay node tries to recover the received source message and re-encodes part of the decoded message for transmission to satisfy the decoding requirements for the following relay node or the destination node. In order to construct practical polar codes, the nested structures are developed based on this protocol and the information sets corresponding to the partial messages forwarded are also calculated. The proposed scheme is proved to be capable of achieving the theoretical capacity of the degraded MRN-ORCs while still retains the low-complexity feature of polar codes. We perform simulations to testify the practicability of the proposed scheme and compare polar codes by using successive-cancellation list decoder(SCLD) with traditional low-density parity-check(LDPC) codes. The results show that the obtained polar codes provide significant gain.

关键词： cooperative communication multiple-relay networks channel capacity decode-and-forward polar codes

Formation of Singularity for Full Compressible Magnetohydrodynamic Equations with Zero Resistivity in Two Dimensional Bounded Domains

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Acta Mathematicae Applicatae Sinica 2023年第4期39卷 990-1008页

作者： xin zhong School of Mathematics and Statistics Southwest UniversityChongqing 400715China

We are concerned with singularity formation of strong solutions to the two-dimensional(2D)full compressible magnetohydrodynamic equations with zero resistivity in a bounded *** energy method and critical Sobolev inequalities of logarithmic type,we show that the strong solution exists globally if the temporal integral of the maximum norm of the deformation tensor is *** result is the same as Ponce’s criterion for 3D incompressible Euler *** particular,it is independent of the magnetic field and ***,the initial vacuum states are allowed.

关键词： full compressible magnetohydrodynamic equations zero resistivity formation of singularity

Dynamic self-assembly of block copolymers regulated by time-varying building block composition via reversible chemical reaction

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Science China Chemistry 2019年第12期62卷 1666-1674页

作者： duo Xu Li Zhao Kuo Zhang zhong-Yuan Lu State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryJilin UniversityChangchun 130023China College of Life Sciences Jilin UniversityChangchun 130012China

Dynamic self-assembly processes occurring out of thermodynamic equilibrium underlie many forms of adaptive and intelligent behaviors in natural *** of the continuous input of energy,the dynamic self-assembly provides the opportunity for creating structures that are unattainable in equilibrium *** this paper,we propose a strategy in the dynamic self-assembly of amphiphilic block copolymers regulated by reversible chemical *** time-dependently tuning the reaction direction in the simulations,the amphiphilicity of building block keeps changing *** on this dynamic process,we can obtain exotic self-assembled vesicle with surface pores which is otherwise metastable in an equilibrium *** effects induced by the type of chemical reaction and the reaction period are *** at short reaction period in suitable reversible reaction,novel self-assembly structure *** is attributed to the competition of reaction and diffusion in the dynamic process,by which the local component of building blocks alters a lot,leading to large local surface tension resulting in the formation of perforated *** order to predict the assembled structure in a dynamic process,we build up the relationship between component ratio P,the diffusion effect parameter Pdiff and assembled *** dynamic self-assembly regulated by chemical reaction holds great promise as a rational strategy to realize exotic functional materials that are not easily obtained in equilibrium.

关键词： dynamic self-assembly block copolymer reversible reaction computer simulation