检索结果-南通市图书馆

Impact of Sub-chronic Aluminium-maltolate Exposure on Catabolism of Amyloid Precursor Protein in Rats

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2013年第6期26卷 445-452页

作者： LIANG Rui feng LI Wei Qing WANG hong WANG Jun Xia niu Qiao Department of Occupational Health School of Public HealthShanxi Medical University Department of Environmental Health School of Public HealthShanxi Medical University

Objective To investigate the impact of sub-chronic Aluminium-maltolate [Al（mal）s] exposure on the catabolism of amyloid precursor protein （APP） in rats. Methods Forty adult male Sprague-Dawley （SD） rats were randomly divided into five groups： the control group, the maltolate group （7.56 mg/kg BW）, and the Al（mal）s groups （0.27, 0.54, and 1.08 mg/kg BW, respectively）. Control rats were administered with 0.9% normal saline through intraperitoneal （i.p.） injection. Maltolate and Al（mal）s were administered to the rats also through i.p. injections. Administration was conducted daily for two months. Rat neural behavior was examined using open field tests （OFT）. And the protein expressions and their mRNAs transcription related with APP catabolism were studied using enzyme-linked immunosorbent assay （ELISA） and real-time polymerase chain reaction （RT-PCR）. Results The expressions of APP, 13-site APP cleaving enzyme 1 （BACEI） and presenilin-1 （PSi） proteins and their mRNAs transcription increased gradually with the increase of Al（mal）3 doses （P〈0.05）. The enzyme activity of BACEI in the 0.54 and 1.08 mg/kg Al（mal）s groups increased significantly （P〈0.05）. The expression of 8-amyloid protein （AS） 1-40 gradually decreased while the protein expression of A81-42 increased gradually with the increase of Al（mal）s doses （P〈0.05）. Conclusion Result from our study suggested that one of the possible mechanisms that Al（mal）s can cause neurotoxicity is that Al（mal）s can increase the generation of A81-42 by facilitating the expressions of APP, β-, and γ-secretase.

关键词： Aluminium-maltolate Amyloid precursor protein 6-amyloid protein Rat

Area Efficient Pattern Representation of Binary Neural Networks on RRAM

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2021年第5期36卷 1155-1166页

作者： feng Wang Guo-Jie Luo Guang-Yu Sun Yu-Hao Wang Di-Min niu hong-Zhong Zheng Center for Energy-Efficient Computing and Applications Peking UniversityBeijing 100871China Pingtouge Alibaba GroupHangzhou 310052China

Resistive random access memory(RRAM)has been demonstrated to implement multiply-and-accumulate(MAC)operations using a highly parallel analog fashion,which dramatically accelerates the convolutional neural networks(CNNs).Since CNNs require considerable converters between analog crossbars and digital peripheral circuits,recent studies map the binary neural networks(BNNs)onto RRAM and binarize the weights to{+1,-1}.However,two mainstream representations for BNN weights introduce patterns of redundant 0s and 1s when dealing with negative *** this work,we reduce the area of redundant 0s and 1s by proposing a BNN weight representation framework based on the novel pattern representation and a corresponding ***,we spilt the weight matrix into several small matrices by clustering adjacent columns ***,we extract 1s'patterns,i.e.,the submatrices only containing 1s,from the small weight matrix,such that each final output can be represented by the sum of several ***,we map these patterns onto RRAM crossbars,including pattern computation crossbars(PCCs)and pattern accumulation crossbars(PACs).Finally,we compare the pattern representation with two mainstream representations and adopt the more area efficient *** evaluation results demonstrate that our framework can save over 20%of crossbar area effectively,compared with two mainstream representations.

关键词： binary neural network(BNN) pattern resistive random access memory(RRAM)

Local events-based fast RTM surface-offset gathers via dip-guided interpolation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2021年第3期18卷 773-782页

作者： Yang Zhao feng-Lin niu Lei Fu Cheng Cheng Jin-hong Chen Shou-Dong Huo State Key Laboratory of Petroleum Resources and Prospecting Unconventional Petroleum Research InstituteChina University of PetroleumBeijing 100083China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTXUSA Department of Earth and Planetary Science University of CaliforniaBerkeleyCAUSA Aramco Research Center Aramco Services CompanyHoustonTXUSA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

Reverse Time Migration(RTM)Surface Ofset Gathers(SOGs)are demonstrated to deliver more superior residual dip information than ray-based *** appears more powerful in complex geological settings,such as salt ***,the computational cost of constructing RTM SOGs is a big challenge in applying it to 3D feld *** tackle this challenge,we propose a novel method using dips of local events as a guide for RTM gather *** residual-dip information of the SOGs is created by connecting local events from depth-domain to time-domain via ray *** proposed method is validated by a synthetic experiment and a feld *** mitigates the computational cost by an order of magnitude while producing comparable results as fully computed RTM SOGs.

关键词： Surface-ofset gathers Reverse-time migration Dip-guided interpolation Reduced costs Local-event raytracing

Universal composable secure protocol for EPC system

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 115-121,128页

作者： XIAO feng ZHOU Ya-jian ZHOU Jing-xian ZHU hong-liang niu Xin-xin Information Security Center Beijing University of Posts and Telecommunications

As an important component of internet of things, electronic product code （EPC） system is widely used in many areas. However, the mass deployment of EPC system is frequently degraded by security and privacy problems. Therefore, the major researches focus on the design of a secure EPC system with high efficiency. This paper discusses the security requirements of EPC system and presents a universal composable （UC） model for EPC system, the ideal functionality of EPC system is also formally defined with the UC framework. Then a secure protocol for EPC system under UC framework is proposed and the analysis of security and performance of the proposed protocol is given, in comparison with other protocols, the results show that the proposed protocol is UC secure and can provide privacy protection, untraceability, authorized access, anonymity and concurrent security for EPC system. Furthermore, less computation and storage resource are required by the proposed protocol.

关键词： EPC system universal composable secure protocol privacy protection

CFD simulation of micro-particle trapping under water tweezers

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2014年第3期2卷 259-264页

作者： Xin-Hua Yi Xiao-Min Cheng feng-Lian niu hong-Chao Fan School of Mechanical Engineering Ningbo University of Technology School of Mechanical and Electrical Engineering Ningbo Dahongying University

In early research, capture and manipulation of particles were mainly achieved by means of light, electricity and plasma in micro-fabficaton and micro-assembly. A new method is proposed using micro-water jet to form water tweezers to capture solid particles and implement position control of micro-particles. This paper analyzes the basic prin- ciple of water tweezers, and the discrete element method and smoothed particle hydrodynamics method are employed to establish a solid-liquid coupling model used in analyzing the trapping mechanism. A flow field model is set up to simulate dynamic characteristic of water tweezers based on computa- tional fluid dynamics （CFD）. Selection of boundary conditions, initial guess, solver control and convergence strategies of the model are discussed. Velocity and pressure of streamline are predicted and discussed under certain input conditions. Simu- lation results demonstrate that it is an efficiently theoretical method to eventually trap solid particles by water tweezers.

关键词： Water tweezers Micro-particle trapping Computational fluid dynamics (CFD) Boundary condition

Selective flotation separation of andalusite and quartz and its mechanism

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2019年第9期26卷 1059-1068页

作者： Yan-ping niu Chuan-yao Sun Wan-zhong Yin Xing-rong Zhang hong-feng Xu Xu Zhang College of Resources and Civil Engineering Northeastern UniversityShenyang 110000China State Key Laboratory of Mineral Processing BGRIMM Technology GroupBeijing 100160China The Research Center of Experimental Testing for Geology and Minerals in Heilongjiang Province Harbin 150000China Heilongjiang Mining Group Co. Ltd. Harbin 150000China

The separation of andalusite and quartz was investigated in the sodium oleate flotation system, and its mechanism was studied by solution chemical calculation, zeta-potential tests, Fourier transform infrared spectroscopic(FTIR), and X-ray photoelectron spectroscopic(XPS). The flotation tests results show that FeCl3·6H2O has a strong activation effect on andalusite and quartz and citric acid has a strong inhibitory effect on activated quartz, thus increasing the floatability difference between quartz and andalusite when the pulp p H is approximately 8. The FTIR, Zeta potential, and XPS analyses combined with the chemical calculation of flotation reagent solutions demonstrate that Fe forms hydroxide precipitates on the surface of andalusite and quartz and that oleate anions and metal ions adsorb onto the surface of the minerals. The elements Al and Fe can be chemically reacted. The anions in citric acid have different degrees of dissolution of Fe on the andalusite and quartz surfaces, thereby selectively eliminating the activation of the elemental Fe on andalusite and quartz and increasing the floatability of andalusite, leading to a better separation effect between andalusite and quartz.

关键词： andalusite quartz flotation mechanism zeta potential Fourier infrared spectrum analysis X-ray photoelectron energy spectrum analysis

Ar adsorptions on Al (111) and Ir (111) surfaces:a first-principles study

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第2期21卷 437-444页

作者： niu Wen-Xia Zhang hong Institution of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China College of Physical Science and Technology Sichuan UniversityChengdu 610065China

We investigate the adsorptions of Ar on Al （111） and Ir （111） surfaces at the four high symmetry sites, i.e., top, bridge, fcc- and hcp-hollow sites at the coverage of 0.25 monolayer （ML） using the density functional theory within the generalized gradient approximation of Perdew, Burke and Ernzerhof functions. The geometric structures, the binding energies, the electronic properties of argon atoms adsorbed on Al （111） and Ir （111） surfaces, the difference in electron density between on the Al （111） surface and on the Ir （111） surface and the total density of states are calculated. Our studies indicate that the most stable adsorption site of Ar on the Al （111） surface is found to be the fcc-hollow site for the （2 x 2） structure. The corresponding binding energy of an argon atom at this site is 0.538 eV/Ar atom at a coverage of 0.25 ML. For the Ar adsorption on Ir （111） surface at the same coverage, the most favourable site is the hcp-hollow site, with a corresponding binding energy of 0.493 eV. The total density of states （TDOS） is analysed for Ar adsorption on Al （111） surface and it is concluded that the adsorption behaviour is dominated by the interaction between 3s, 3p orbits of Ar atom and the 3p orbit of the base Al metal and the formation of sp hybrid orbital. For Ar adsorption on Ir （111） surface, the conclusion is that the main interaction in the process of Ar adsorption on Ir （111） surface comes from the 3s and 3p orbits of argon atom and 5d orbit of Ir atom.

关键词： density-functional theory binding energy adsorption electronic structure

Effects of sweep angles on turbulent separation behaviors induced by blunt fin

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第3期35卷 90-97页

作者： Dundian GANG Shihe YI feng ZHANG Haibo niu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410072China

An experimental study was conducted on turbulent separation behaviors induced by blunt fins with different sweep angles at Mach number *** Nano-particle based Planar Laser Scattering technique(NPLS)was applied to visualize the flowfield,complemented by pressure *** angles of the fins were 10°,20°,...,60°,with the same leading edge diameter of 10 *** structures of the interference flowfield induced by blunt fins have been obtained,including the shock systems and *** was found that the features and shapes of the detached shock depended on sweep *** sweep angle30°.Two peak values were detected on the centerline pressure *** first peak did not rely on sweep angle,while the second peak value decreased with increasing sweep angle.

关键词： Blunt fin Flow separation Hypersonic turbulent boundary layer NPLS SIFT

同方期刊数据库

Systematics on production of superheavy nuclei Z=119-122 in fusion-evaporation reactions

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2021年第10期32卷 59-71页

作者： Fei niu Peng-Hui Chen Zhao-Qing feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510640China College of Electrical Energy and Power Engineering Yangzhou UniversityYangzhou 225000China

The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system *** Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear *** production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from *** evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically *** combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?*** obtained that the production cross sections sensitively depend on the neutron richness of the reaction *** structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.

关键词： Dinuclear system model Fusion-evaporation reactions Superheavy nuclei Cross sections