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Science china(Technological sciences) 2005年第Z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3.1. Institute of Mechanics, chinese academy of {2., Beijing 100080, {3. 2. graduate school, chinese academy of {2., Beijing 100060, {3. 3. Tropical Marine Science Institute, National university of Singapore, Singapore 1192.0 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100060 China Tropical Marine Science Institute National University of Singapore Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. Institute of Oceanology, chinese {3. of {2., Qingdao 2.6071, {3. 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, {3. 3. graduate school of the chinese {3. of {2., Beijing 10003., {3. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate school of the {2. {3. of sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2.3.1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese academy of Fishery {2., Qingdao 2.6071, {3. 2. Institute of Oceanology, chinese academy of {2., Qingdao 2.6071, {3. 3. The graduate {13. of the chinese academy of {2., Beijing 10003., {3. Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China The graduate school of the {2. {3. of sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2.59 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 2..6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2. of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42.. In decreasing order, the 2. most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (2.4), AAT (92., A (56), AAG (2.), ATC (2.), ATAG (2.), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2. GU Yidong3. LIN Baojun3.& guo Jiong3.1. Center for Space Science and Applied Research, chinese {2. of sciences, Beijing 100080, {3. 2. graduate school of the chinese {2. of sciences, Beijing 10003., {3. 3. General Establishment of Space Science and Application, chinese {2. of sciences, Beijing 100080, {3. Correspondence should be addressed to L Congmin Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate school of the {2. {3. of sciences Beijing China General Establishment of Space Science and Application Chinese Academy of Sciences Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Power functions with low uniformity on odd characteristic finite fields

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Science china Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3.& WANG XueLi 2.1 school of mathematical {2.,Luoyang Normal {3.,Luoyang 47102.,china 2.school of mathematical {2.,South china Normal {3.,Guangzhou 51063.,china 3.State Key Laboratory of Information Security,graduate {3. of chinese academy of {2.,Beijing 100049,china school of mathematical {2. Luoyang Normal University Luoyang China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China school of mathematical {2. South China Normal University Guangzhou China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field

Artificial synaptic simulating pain-perceptual nociceptor and brain-inspired computing based on Au/Bi_(3.2.La_(0.8)Ti_(3.O_(12./ITO memristor

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Journal of Materiomics 2024年第6期10卷 1308-1316页

作者： Hao Chen Zhihao Shen Wen-Tao guo Yan-ping Jiang Wenhua Li Dan Zhang Zhenhua {2. Qi-Jun Sun Xin-Gui {2. school of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou510006China

Recently, memristors have garnered widespread attention as neuromorphic devices that can simulate synaptic behavior, holding promise for future commercial applications in neuromorphic computing. In this paper, we present a memristor with an Au/Bi_(3.2.La_(0.8)Ti_(3.O_(12. (BLTO)/ITO structure, demonstrating a switching ratio of nearly 103.over a duration of 104 s. It successfully simulates a range of synaptic behaviors, including long-term potentiation and depression, paired-pulse facilitation, spike-timing-dependent plasticity, spike-rate-dependent plasticity etc. Interestingly, we also employ it to simulate pain threshold, sensitization, and desensitization behaviors of pain-perceptual nociceptor (PPN). Lastly, by introducing memristor differential pairs (1T1R-1T1R), we train a neural network, effectively simplifying the learning process, reducing training time, and achieving a handwriting digit recognition accuracy of up to 97.19 %. Overall, the proposed device holds immense potential in the field of neuromorphic computing, offering possibilities for the next generation of high-performance neuromorphic computing chips.

关键词： Artificial synapse Memristor Resistive switching Pain-perceptual nociceptor Neuromorphic computing

Expression of Monomeric Insulin Precursor in Pichia pastoris and Its Conversion into Monomeric B2. Lys Destripeptide Insulin by Tryptic Hydrolysis

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Acta Biochimica et Biophysica Sinica 2005年第4期37卷 234-240页

作者： Jin-guo DING~(1,3. Jian FEI~2.Da-Fu CUI~1 You-Shang ZHANG~1 ~1Institute of Biochemistry and Cell Biology,and ~2.odel Organism Research Center,Shanghai Institutes for Biologicol {3., {2. academy of {3.,Shanghai 2.003.,china ~3.9} school of the {2. academy of {3.,Shanghai 2.003.,china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China graduate school of the {2. {3. of sciences Shanghai 2.003. China Model Organism Research Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Monomeric B2. Lys destripeptide insulin (B2. Lys DTrI) was designed and produced from itsprecursor expressed in Pichia pastoris through tryptic hydrolysis instead of the less efficient *** monomeric B2. Lys DTrI precursor (MIP) was purified from a cultured medium *** by a combination of hydrophobic,size-exclusion,and ion-exchange *** purifiedMIP was converted,by tryptic hydrolysis,to B2. Lys DTrI,which was then purified by ion-exchangechromatography to homogeneity as assessed by native gel electrophoresis,HPLC,amino acid composition,and electrospray mass-spectrometric analysis.B2. Lys DTrI exhibited superior monomeric properties insize-exclusion *** yield of MIP was 2.0 mg per liter of culture,and the overall yield ofpurified B2. Lys DTrI from the crude MIP was 70%.The in vivo biological activity of B2. Lys DTrI asdetermined by the mouse convulsion assay was 2. U/mg,identical to that obtained by semisynthesis.

关键词： monomeric B2. Lys destripeptide insulin tryptic hydrolysis Pichia pastoris

Research progress on metal-organic framework compounds(MOFs)in electrocatalysis

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Journal of Environmental sciences 2024年第7期141卷 261-276页

作者： Yutong guo Shunzheng Zhao Xiaolong tang Honghong Yi Department of Environmental Science and Engineering School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials ***,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing *** review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.

关键词： Metal-organic frame compounds Electrocatalysis Oxidation-reduction Nitrogen fixation to synthesize ammonia Carbon dioxide reduction

The nitrogen transformation behavior based on the pyrolysis products of wheat straw

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chinese Journal of Chemical Engineering 2024年第7期71卷 58-65页

作者： Shun guo Yunfei Li Shengwei tang Tao Zhang school of Chemical Engineering Sichuan UniversityChengdu 610065China

In order to provide basic design parameters for the industrial pyrolysis process,the transformation behavior of nitrogen was investigated using wheat straw as raw *** distributions of nitrogen in pyrolysis char,oil,and gas were obtained and the nitrogenous components in the products were analyzed systematically by X-ray photoelectron spectroscopy(XPS),pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)and thermogravimetric-Fourier transform infrared spectrometry(TG-FTIR).The nitrogen distribution ranges of the pyrolysis char,oil,and gas were 3..3.%–54.82.,3.0}87%–40.94%and 10.2.%–2..83.,*** nitrogen was retained in char at lower pyrolysis temperature and the nitrogen distribution of oil was from rise to decline with increasing *** most abundant N-containing compounds in three-phase products were pyrrole-N,amines,and HCN,*** addition,the transformation mechanism of nitrogen from wheat straw to pyrolysis products was concluded.

关键词： Pyrolysis Nitrogen transformation Wheat straw Py-GC/MS TG-FTIR

Geographical Agglomeration of chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2. Zheng Wei3.1. Institute of Geographical sciences and Natural Resources Research, chinese {2. of sciences, Beijing 100101, china 2. graduate school of the chinese {2. of sciences, Beijing 10003., china 3. school of Geography, Beijing Normal {12., Beijing 100875, china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate school of the {2. {3. of sciences Beijing 100039 China school of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of chinese manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of chinese manu- facturing industries in 1996, {3.01 and {3.04, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–{3.04.

关键词： industrial agglomeration manufacturing industries the MS index