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稀有金属材料与工程 2011年第S4期40卷 226-230页

作者： Qian Jiangang1,zhang Jiaxiang1,2.Li Shuqing2.wang Chun2.Gong Shuili2.{2. of Chemistry and Environment,Beijing university of Aeronautics and Astronautics,Beijing 100191,china2.5} and technology on Power Beam Processes Laboratory,Avic Beijing Aeronautical Manufacturing technology Research Institute,Beijing 10002.,china Beijing Univ Aeronaut & Astronaut Sch Chem & Environm Beijing 100191 Peoples R China Avic Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

An Al-Si/Al+Al2.3 coa{1. was prepared on an AZ91. Mg alloy substrate by laser cladding of the plasma-sprayed coa{1..X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the phases and to study the morphology,*** adhesion strength and the porosity ratio of the coa{1. were measured by using a tensile tes{1. machine and an optical microscope (OM),*** microhardness was measured using a micro Vickers hardness *** results show that after laser cladding,the adhesion strength of the coa{1. increased from 1..78 to 2..1. *** the laser power was 1.00W,the metastable γ-Al2.3 phase in the coa{1. transformed completely into the stable α-Al2.3 *** with the increase of the laser power,the porosity ratio of the coa{1. *** when the laser power was over 1.00W,the porosity ratio *** microhardness of the surface was the hardest which was improved from HV0.051.0} to *** larger the power of the laser was,the harder the coa{1. *** when the power was 1.00W,the microhardness increased slightly,even the microhardness of the internal decreased.

关键词： laser-clad plasma-sprayed magnesium alloy Al-Si/Al+Al2.3 coating

Benthodytes occidentpalauta ***.,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the west of Kyushu-Palau Ridge in the Western Pacific Ocean

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Journal of Oceanology and Limnology 2024年第1期42卷 252-262页

作者： Chongzhen YUAN Chunsheng wang Dongsheng {1. Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China school of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China

Benthodytes occidentpalauta *** collected from the Kyushu-Palau Ridge at a depth of 5481.m in *** new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a rough mid-ventral surface without tube *** dorsal deposits are rod-shaped and *** types of papillae deposits as crosses with four arms with central bipartite *** deposits are *** ossicles are rod-shaped with end *** deposits are rodshaped,tripartite,and *** phylogenetic analyses based on cytochrome oxidase subunit 1.COI)and 1.S individually and a concatenated dataset of COI and 1.S genes of this species support that *** *** to Benthodytes.

关键词： Holothuroidea Benthodytes cytochrome oxidase subunit 1.COI) 1.S phylogenetic analysis

Embedded DHT overlays in virtual computing environments

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science{1.(Information sciences) 2010年第3期53卷 483-493页

作者： zhang YiMing, LU XiCheng & LI DongSheng 1.ational Laboratory for Parallel and Distributed Processing (PDL), Changsha 41.073,{1. 2.2. of computer, National university of Defense technology, Changsha 41.073,{1. 1. National Laboratory for Parallel and Distributed Processing (PDL) Changsha 410073 China

With the rapid development of computing and networking technologies, people propose to build harmonious, trusted and transparent Internet-based virtual computing environments (iVCE). The overlay-based organization of dynamic Internet resources is an important approach for iVCE to realizing efficient resource sharing. DHT-based overlays are scalable, low-latency and highly available; however, the current DHT overlay (SKY) in iVCE cannot satisfy the "trust" requirements of Internet applications. To address this problem, in this paper we modify SKY and propose TrustedSKY, an embedded DHT overlay technique in iVCE which supports applications to select trusted nodes to form a "trusted subgroup" in the base overlay and realize secure and trusted DHT routing.

关键词： Internet-based virtual computing environment (iVCE) DHT overlay TrustedSKY

Multi-scenario Simulation of the Impact of Land Use Change on the Ecosystem Service Value in the Suzhou-Wuxi-Changzhou Metropolitan Area,china

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Chinese Geographical science 2024年第1期34卷 79-92页

作者： wang Bin HU Chunguang {1. Yushuo Department of Tourism Management Soochow UniversitySuzhou215123China Academy of Culture and Tourism Research Soochow UniversitySuzhou215123China school of Architecture and Urban Planning Huazhong University of Science and TechnologyWuhan430074China hubei Engineering and {1. Research Center of Urbanization Wuhan430074China Faculty of Culture Tourism Shanxi University of Finance and EconomicsTaiyuan030006China

As the most economically developed metropolitan area in china’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem service value(ESV).Based on the patterns of land use change and the ESV change in Su-Xi-Chang metropolitan area from 2.00 to 2.2.,we set up four scenarios:natural development scenario,urban development scenario,arable land protection scenario and ecological protection scenario,and simulated the impact of land use changes on the ESV in these *** results showed that:1) the area of built-up land in the Su-XiChang metropolitan area increased significantly from 2.00 to 2.2.,and the area of other types of land *** land underwent the highest transfer-out area,and was primarily converted into built-up *** total ESV of Su-Xi-Chang metropolitan area increased initially then declined from 2.00–2.2.,and the value of almost all individual ecosystem services decreased.2. Population density,GDP per area,night lighting intensity,and road network density can negatively impact the ESV.3) The total ESV loss under the natural development and urban development scenarios was high,and the expansion of the built-up land and the drastic shrinkage of the arable land contributed to the ESV decline under both *** total ESV under arable land protection and ecological protection scenarios increases,and therefore these scenarios are suitable for future land use optimization in *** study could provide a certain reference for land use planning and allocation,and offer guidance for the rational allocation of land resources.

关键词： multiple scenarios land use simulation ecosystem service value(ESV) Patch-Generating Land Use Simulation(PLUS)model Suzhou-Wuxi-Changzhou(Su-Xi-Chang)metropolitan area

A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： Zhi Dan wang Guo Ming {1. school of Physical and Mathematical {1.s Nanjing Tech UniversityNanjing 211816P.R.China Frontiers science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2. and certain quasi-orthogonality on a subspace of L^(2.,in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2.:={(x,t,λ)∈R^(n+1.×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1.2. Meng Fei~1.{1. Yijun~1.Gao Xiaorong~1.Gao Shangkai~(1.*) (1.Department of Biomedical Engineering,school of Medicine,Tsinghua {2.,Beijing 1.0084,china 2.Department of Electronic Engineering,school of Information,Nanchang {2.,Nanchang 33002.,china) [a]Department of Biomedical Engineering School of Medicine TsinghuaUniversity Beijing China [b]Department of Electronic Engineering School of Information Nanchang University Nanchang China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discrimina{1. different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91. on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

Analysis of leakage current in GaAs micro-solar cell arrays

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science{1.(Technological sciences) 2010年第5期53卷 1240-1246页

作者： wang YanShuo1,CHEN NuoFu1,2.3,zhang Xingwang1,BAI YiMing1,wang Yu1,HUANG TianMao1,zhang Han1 & SHI HuiWei1 1 Key Laboratory of Semiconductor Materials science,Institute of Semiconductors,Chinese Academy of sciences,PO Box 912.Beijing 100083,china 2.school of Renewable Energy Engineering,North china Electric Power university,Beijing 102.06,china 3 National Laboratory of Micro-Gravity,Institute of Mechanics,Chinese Academy of sciences,Beijing 100080,china 1. Key Laboratory of Semiconductor Materials science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China2. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China3. National Laboratory of Micro-Gravity Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The output characteristics of micro-solar cell arrays are analyzed on the basis of a modified model in which the shunt resistance between cell lines results in current *** modification mainly consists of adding a shunt resistor network to the traditional *** obtained results agree well with the reported experimental *** calculation results demonstrate that leakage current in substrate affects seriously the performance of GaAs micro-solar cell *** performance of arrays can be improved by reducing the number of cells per *** addition,at a certain level of integration,an appropriate space occupancy rate of the single cell is recommended for ensuring high open circuit voltages,and it is more appropriate to set the rates at 80%-90% through the calculation.

关键词： micro-solar cell MEMS(micro-electromechanical systems) leakage current

An FPGA Implementation of GF（p） Elliptic Curve Cryptographic Coprocessor

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An FPGA Implementation of GF（p） Elliptic Curve Cryptograph...

Tuning microstructures of Mg-Ce-Ni hydrogen storage alloys via Cu and carbon nanotube additions

The 1.t Chinese Conference on Trusted Computing and Information Security

作者： LIU Yu-zhen ,QIN Zhong-ping, zhang Huan-guo school of {2., wuhan university, wuhan 430072. hubei, china school of Software, Huazhong university of science and technology, wuhan 430074, hubei, china

＜正＞ A GF（p） elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array （FPGA）. The focus of the coprocessor is on the most critical, complicated and time-consuming point multiplications. The technique of coordinates conversion and fast multiplication algorithm of two large integers are utilized to avoid frequent inversions and to accelerate the field multiplications used in point multiplications. The characteristic of hardware parallelism is considered in the implementation of point multiplications. The coprocessor implemented on XILINX XC2.3000 computes a point multiplication for an arbitrary point on a curve defined over GF（2.92.2.4-1. with the frequency of 1. MHz in 4. 40 ms in the average case and 5. 74 ms in the worst case. At the same circumstance, the coprocessor implemented on XILINX XC2.4000 takes 2. 2.ms in the average case and 2. 88 ms in the worst case.

关键词： elliptic curve cryptosystems cryptographic coprocessor cryptography information security

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Nano Research 2024年第8期17卷 7203-7211页

作者： Linlin zhang Liang Xiong Bingyang Gao Qingyun Shi Ying {1. Zhiya Han Zhenhua zhang Chunli {1. Limin {1. Yong Cheng State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China school of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Purification Equipment Research Institute of CSIC Handan 056002China

Mg-based alloys are regarded as highly promising materials for hydrogen *** significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical *** this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are *** results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2.u-1.NTs with an amorphous/nanocrystalline structure compared to the other experimental ***,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental *** noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 ***,the activation energy for dehydrogenation is decreased to 64.71.kJ·mol^(–1..This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.

关键词： Mg-Ni-Ce alloy hydrogen storage amorphous/nanocrystalline structure kinetics Cu and carbon nanotubes(CNTs)codoping

A kinetic resolution accompanied chirality transformation process for asymmetric synthesis of chiral phenol,oxaziridine,andα-hydroxyl cyclic ketone

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science{1. Chemistry 2024年第9期67卷 2989-2997页

作者： Pengxin wang Xiaoyong {1. Lingqing wang Rui wang Dongxu Yang Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences&Research Unit of Peptide ScienceChinese Academy of Medical SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China school of {1.s Great Bay UniversityDongguan 523000China Institute of Systems and Physical Biology Shenzhen Bay LaboratoryShenzhen 518055China

Chirality transformation is a basic,attractive,and important strategy for obtaining enantioenriched products with desired chiral *** reported chirality conversion reaction often involves the process from one type of chirality to another *** better utilize the chirality transformation strategy for obtaining two or more products with different chiral elements in a single reaction,a new method of kinetic resolution accompanied by a chirality transformation protocol is proposed and successfully realized in this *** process is used for the asymmetric oxidation of phenol compounds along with the kinetic resolution of oxaziridines.A wide scope of products,including axially chiral phenols,oxaziridines,andα-hydroxyl cyclic ketones were smoothly obtained in high levels of yields and enantioselectivities in the developed *** products can be readily used for the synthesis of various types of chiral ligands,which are potential choices for other catalytic asymmetric reactions.

关键词： chirality transformation kinetic resolution accompanied axially chiral phenols chiral oxaziridines