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Effect of surface passivation on optical and electronic properties of ultrathin silicon nanosheets

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Science China(information Sciences) 2012年第6期55卷 1469-1474页

作者： WANG Le 1,2,WU Ke 2,DONG QianMin 1,LI XiaoYan 1,XIONG SiYu 1,XU LeiTing 3 & LIANG Pei 1 1 college Of Electronic Science and engineering,China Jiliang University,Hangzhou 310018,China 2 Department of engineering,Zhejiang University,Hangzhou 310000,China 3 Hang Zhou Urban Infrastructure Construction and Development Center,Hangzhou 310000,China college Of Electronic Science and engineering China Jiliang University Hangzhou China Department of engineering Zhejiang University Hangzhou China Hang Zhou Urban Infrastructure Construction and Development Center Hangzhou China

The binding energy,electronic structure and optical properties of H-,H 3 C-,and HS-cluster-passivated ultrathin silicon (single-layer and double-layer) nanosheets were calculated using density functional theory based on the plane-wave ultra-soft ***,the most stable configuration was selected from passivated configurations according to the principle of lowest energy after calculating their total *** the density of state and the band structure of the different passivated systems were *** was found that different passivation clusters could affect the forbidden band,theremore the passivated cluster with sulfur could greatly decrease the width of the forbidden band through electron ***,the light absorption and reflection properties were also *** results were conducive to the development of silicon-based optoelectronic devices.

关键词： density functional theory surface passivation super-thin silicon nanosheets electronic structure

Er^(3+)-Yb^(3+) codoped borosilicate glass for optical thermometry

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 848-851页

作者： FENG ZhiQing1,BAI Lan2,CAO BaoSheng1,GONG LiDong3 & DONG Bin1,4 1 School of Science,Dalian Nationalities University,Dalian 116600,China 2 college of Electromechanical & information engineering,Dalian Nationalities University,Dalian 116600,China 3 School of Chemistry and Chemical engineering,Dalian 116029,China 4 Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China School of Science Dalian Nationalities University Dalian China college of Electromechanical & information engineering Dalian Nationalities University Dalian China School of Chemistry and Chemical engineering Dalian China Institute of Physics Chinese Academy of Sciences Beijing China

Infrared to green up-conversion emissions centered at the wavelengths of about 524 and 550 nm of the Er3+-Yb3+ codoped borosilicate glass are recorded,using a 978 nm semiconductor laser diode(LD) as an excitation *** fluorescence intensity ratio(FIR) of the green up-conversion emissions at about 524 and 550 nm in the Er3+-Yb3+ codoped borosilicate glass has been studied as a function of temperature over the temperature range of 295-873 *** maximum sensitivity and the temperature resolution derived from the FIR of the green up-conversion emissions are approximately 0.0038 K-1 and 0.2 K,*** is demonstrated that the prototype optical temperature sensor based on the FIR technique from the green up-conversion emissions in the Er3+-Yb3+ codoped borosilicate glass plays a major role in temperature measurement.

关键词： Er3+-Yb3+ codoped optical temperature sensor fluorescence intensity ratio

Influence of p-layer on the performance of n-i-p μc-Si:H thin film solar cells

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 2042-2046页

作者： YUAN YuJie 1,2,ZHANG KaiLiang 1,2,WEI Zhen 1,2 & GENG XinHua 3 1 college of Electronics information engineering,Tianjin University of Technology,Tianjin 300384,China 2 Tianjin Key Laboratory of Film Electronic and Communication Devices,Tianjin University of Technology,Tianjin 300384,China 3 Institute of Photo-Electronics Thin Film Devices and Technique,Nankai University,Tianjin 300071,China college of Electronics information engineering Tianjin University of Technology Tianjin China Tianjin Key Laboratory of Film Electronic and Communication Devices Tianjin University of Technology Tianjin China Institute of Photo-Electronics Thin Film Devices and Technique Nankai University Tianjin China

The high pressure radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) process was adopted to prepare the n-i-p microcrystalline silicon solar cells,the influence of p-type layers on the performance of the solar cells was investigated,and the optimum p layer suited to the n-i-p microcrystalline silicon solar cells was *** experimental results demonstrate that the performance of the solar cells can be highly affected by the structural and optical properties of the p-layers,and the performance of solar cells can be greatly improved by optimizing p *** have achieved an initial active-area efficiency of 8.17% (V oc =0.49 V,J sc =24.9 mA/cm 2 ,FF=67%) for the μc-Si:H single-junction n-i-p solar cells and an initial active-area efficiency of 10.93% (V oc =1.31 V,J sc =13.09 mA/cm 2 ,FF=64%) for the a-Si:H/μc-Si:H tandem n-i-p solar cells.

关键词： microcrystalline silicon solar cells quantum confinement effect p-type layers

木质素磺酸钙增强花岗岩残积土微生物固化效果研究

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土木工程学报 2024年第3期57卷 123-132页

作者：朱文羲邓华锋李建林肖瑶熊雨程雷三峡大学三峡库区地质灾害教育部重点实验室湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002

为提升微生物固化花岗岩残积土的效果,综合考虑木质素磺酸钙的特点和MICP(Microbial-induced calcite precipitation)作用过程的环境条件,设计进行木质素磺酸钙增强MICP固化花岗岩残积土试验,综合宏观物理力学试验和微细观检测,系统分... 详细信息

为提升微生物固化花岗岩残积土的效果,综合考虑木质素磺酸钙的特点和MICP(Microbial-induced calcite precipitation)作用过程的环境条件,设计进行木质素磺酸钙增强MICP固化花岗岩残积土试验,综合宏观物理力学试验和微细观检测,系统分析木质素磺酸钙对微生物固化花岗岩残积土的增强效果及增强机制。结果表明:①木质素磺酸钙能够显著提高花岗岩残积土微生物加固过程中的胶结物产量,木钙掺量在4.00%左右达到最佳,与常规MICP相比,胶结物生成量提高了48.86%;②木质素磺酸钙的掺入,显著提高了固化体的抗压强度和抵抗变形能力,2.00%~8.00%掺量下固化体的抗压强度提升了4.75%~41.20%,破坏时应变增加16.24%~38.55%;③掺入木质素磺酸钙后,固化体的孔隙大小及孔隙率均有不同程度降低,孔隙率降低了12.97%~37.38%,固化体的整体密实性进一步增强;④木质素磺酸钙的掺入,改善了残积土的孔隙结构,为后续微生物加固提供更好的环境条件;⑤在微生物固化花岗岩残积土过程中掺入木质素磺酸钙后,改善了微生物生长的酸碱环境,丰富了MICP作用过程中的钙源,提升了固菌率,促进了MICP反应,同时改善了碳酸钙沉淀颗粒的大小、性状及排列形式,使得胶结物产量进一步提升,从而提升固化体的整体固化效果。

关键词：木质素磺酸钙 MICP 花岗岩残积土固化效果微观结构

Achievable bit rates of cognitive user with Vandermonde precoder in cognitive radio network

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Science China(information Sciences) 2011年第7期54卷 1471-1480页

作者： XU XiaoRong 1,ZHANG JianWu 1 & ZHENG BaoYu 2 1 college of Telecommunication engineering,Hangzhou Dianzi University,Hangzhou 310018,China 2 Institute of Signal Processing and Transmission,Nanjing University of Posts and Telecommunications,Nanjing 210003,China college of Telecommunication engineering Hangzhou Dianzi University Hangzhou China Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing China

In cognitive radio network (CRN) where primary user (PU) and secondary user (SU) wish to communicate with their corresponding receivers simultaneously over frequency selective fading channels,the interference between PU and SU should be eliminated in order to realize spectrum *** division multiple access (PDMA) that implements Vandermonde precoder in cognitive orthogonal frequency division multiplexing (OFDM) is proposed,which benefits from the frequency selectivity of the cognitive channel to form a frequency *** precoder enables SUs to achieve higher bit rate with optimal power allocation strategy under the condition of PU interference *** and simulation results are presented to prove theoretical *** is shown that,achievable bit rates (ABR) of SU could be achieved with optimal power allocation scheme in ***,it is also verified that,with Vandermonde precoder to form PDMA,SU’s signal-to-noise ratio (SNR) and the target rate of PU could impact the ABR of SU significantly in CRN.

关键词： achievable bit rates (ABR) Vandermonde precoder precoder division multiple access (PDMA) optimal power allocation cognitive radio network (CRN)

Simulating the Folding Pathway of RNA Secondary Structure Using the Modified Ant Colony Algorithm

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Journal of Bionic engineering 2010年第4期7卷 382-389页

作者： Jun Yu~(1,2),Changhai Zhang~(1,2),Yuanning Liu~(1,2),Xin Li~(1,2) 1.college of Computer Science and Technology,Jilin University,Changchun 130012,P.R.China 2.Key Laboratory of Symbolic Computation and Knowledge engineering (Ministry of Education,China) Jilin University,Changchun 130012,P.R.China college of Computer Science and Technology Jilin University Changchun P. R. China Key Laboratory of Symbolic Computation and Knowledge engineering (Ministry of Education China) Jilin University Changchun P. R. China

A new method for simulating the folding pathway of RNA secondary structure using the modified ant colony algorithmis *** a given RNA sequence,the set of all possible stems is obtained and the energy of each stem iscalculated and stored at the initial ***,a more realistic formula is used to compute the energy ofmulti-branch loop in the following *** a folding pathway is simulated,including such processes as constructionof the heuristic information,the rule of initializing the pheromone,the mechanism of choosing the initial andnext stem and the strategy of updating the pheromone between two different *** by testing RNA sequences withknown secondary structures from the public databases,we analyze the experimental data to select appropriate values *** measure indexes show that our procedure is more consistent with phylogenetically proven structures thansoftware RNAstructure sometimes and more effective than the standard Genetic Algorithm.

关键词： RNA secondary structure folding pathway ant colony algorithm

Bioinspired Polarized Optical Flow Enables Turbid Underwater Target Motion Estimation

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Journal of Ocean University of China 2024年第4期23卷 915-923页

作者： CHENG Haoyuan ZHAO Shujie zhu Jinchi YU Hao CHU Jinkui college of engineering Ocean University of ChinaQingdao 266100China Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China

Underwater target motion estimation is a challenge for ocean military and scientific *** this work,we propose a method based on the combination of polarization imaging and optical flow for turbid underwater target *** imaging can reduce the influence of backscattered light and obtain high-quality images *** optical flow shows the motion and structural information of the *** use polarized optical flow to obtain the optical flow field and estimate the target *** experimental results of different targets under varying water turbidity levels illustrate that our method is realizable and *** precision is verified by comparing the results with the precise displacement data and calculating two error *** proposed method based on polarized optical flow can obtain accurate displacement information and a good recognition *** target segmentation based on the Otsu method further proves the superiority of the polarized optical flow under turbid *** study is valuable for target detection and motion estimation in scattering environments.

关键词： turbid underwater motion estimation polarization imaging optical flow

Training, simulation, restoration expert system for power grid

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Journal of Central South University of Technology 2001年第1期8卷 69-73页

作者： LUO An,CHEN Qian (college of information engineering, Central South University, Changsha 410083, China) college of information engineering Central South University Changsha China

The paper introduces some technology for training, simulation, restoration expert system of power grid, the structure of the system including function composition, hardware and software composition are discussed, knowledge representation and the method to establish device graphical library for expert system are given, the fault setting and diagnosis for training and simulation as well as restoration technology with deep first searching arithmetic and heuristic inference are presented. The research provides a good base for developing the training, simulation, restoration system of power companies.

关键词： training simulation restoration expert system power grid

A New (t, n) Threshold Signature Scheme Withstanding the Conspiracy Attack

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 107-110页

作者： XIE Qi 1,2, YU Xiu-yuan 3 1.Department of Mathematics, Zhejiang University, Hangzhou 310027, Zhejiang,China 2.School of information and engineering, Hangzhou Teachers college, Hangzhou 310012, Zhejiang, China 3.Hangzhou Teachers college, Hangzhou 310012, Zhejiang, China Dept. of Math. Zhejiang Univ. Hangzhou 310027 China Sch. of Info. and Eng. Hangzhou Teachers Coll. Hangzhou 310012 China Hangzhou Teachers Coll. Hangzhou 310012 China

A ccmspiracy attack is proposed to show that Wang-Li's scheme is instcure,because any t or more group members can impersonate other t member to sign any message withoutholding the responsibility. To avoid the conspiracy attack, this paper prestentsa new (t,n)threshold signature scheme with traceablt signers. A (t. n) threshold signature scheme allows t ormore group members of the group lo generate a signature on behalf of the group, Any less than tmembers cannot generate a valid signature, andany set of the group cannot impersonate another set ofmembers to sign any message without holding the responsibility. In case of disputes., the thresholdsignature can be opened, so that the original signers ean be traced without repealing the secretkeys.

关键词： cryptography threshold signature conspiracy attack identifier tracing