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Journal of Iron and Steel Research International 2015年第4期22卷 324-329页

作者： xiao-juan ZHEN Pei-qing LA cui-ling LI Su-lei HU State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology

A simple method was developed to produce the nanocrystalline pure iron by aluminothermic reaction cast- ing. The mierostructure of the iron was investigated by optical microseope （OM）, transmission electron microscope （TEM）, electron probe micro-analyzer （EPMA）, scanning electron microscope （SEM） and X-ray diffraction （XRD）. The mechanical performances of nanoerystalline pure iron were tested. It is found that the pure iron consists of nanoerystalline ferrite. For different substrates of eopper and glass, the average grain size of the ferrite was 38 and 35 nm, respectively, which is larger on copper substrate than that on glass. The hardness, compressive strength, tensile strength, and total elongation are 167 and 137 HB, 400 and 500 MPa, 243 and 185 MPa, 16% and 10% on copper substrate and glass suhstrate, respectively. The hardness, tensile strength and total elongation are all larger on copper substrate than those on glass substrate, while the eompressive strength is lower. The large supercooling in the product solidification provides the condition for high nucleation rate and thus leads to nano-grained austenite and final nano-grained ferrite transformed from those small austenite grains.

关键词： nanocrystalline aluminothermic reaction casting pure iron substrate microstructure mechanical property

Space time frequency coding for dual polarization MIMO in hybrid mobile satellite system

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 8-14页

作者： WANG Kai-dong GUO ling-zhi TAO xiao-feng cui Qi-mei Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

The hybrid mobile satellite system operating in a single frequency network （SFN） mode is increasingly becoming attractive. The combination of satellite component （SC） and terrestrial component （TC） promises a better quality of service （QoS）. Multimedia broadcast and multicast services （MBMS） are expected to be prevailed in this kind of system. Several space frequency （SF） or space time （ST） codes have been proposed to enhance the system performance due to the lack of reverse link and omni-directional transmission. However, they mostly consider the system with only one SC and one TC and fail to make full use of available diversities. This paper presents a novel way to realize the dual polarization multiple input multiple output （MIMO） transmission by using the space time frequency （STF） code. The theoretical analysis and simulations indicate that the application of STF code can improve the system performance dramatically. A higher diversity gain can be achieved due to the cooperative transmission of SC and TC, while the coding gain can be enhanced by the reusing of STF code between SCs or TCs. Even if some of the links are lost, it can still work properly and benefit from the STF code. The relative relay can result in a degradation up to 0.5 dB in the coding gain.

关键词： MIMO dual polarization hybrid mobile satellite system SFN STF code diversity gain

Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

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Communications in Theoretical Physics 2024年第7期76卷 134-144页

作者： Da-cheng Ma ling-yi cui Chu-xiao Sun xiao-dan Chi Zheng-Nan XianYu An Du College of Science Northeastern UniversityShenyang 110819China Department of Basic Science Dalian Naval AcademyDalian 116018China Department of Physics College of SciencesShenyang University of Chemical TechnologyShenyang 110142China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityChina Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationChina

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner *** use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each *** the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the *** results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin *** the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be *** work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Nanoribbon magnetic anisotropy long-range magnetic order Heisenberg model transition temperature

Machine Learning Aided Key-Guessing Attack Paradigm Against Logic Block Encryption

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Journal of Computer Science & Technology 2021年第5期36卷 1102-1117页

作者： Yi Zhong Jian-Hua Feng xiao-Xin cui xiao-Le cui Institute of Microelectronics Peking UniversityBeijing 100871China Key Laboratory of Integrated Microsystems Peking University Shenzhen Graduate SchoolShenzhen 518055China

Hardware security remains as a major concern in the circuit design *** block based encryption has been widely adopted as a simple but effective protection *** this paper,the potential threat arising from the rapidly developing field,i.e.,machine learning,is *** illustrate the challenge,this work presents a standard attack paradigm,in which a three-layer neural network and a naive Bayes classifier are utilized to exemplify the key-guessing attack on logic *** with validation results obtained from both combinational and sequential benchmarks,the presented attack scheme can specifically accelerate the decryption process of partial keys,which may serve as a new perspective to reveal the potential vulnerability for current anti-attack designs.

关键词： hardware security logic encryption machine learning neural network naive Bayes classifier

Damming of Large River by Debris Flow: Dynamic Process and Particle Composition

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Journal of Mountain Science 2014年第3期11卷 634-643页

作者： DU cui YAO ling-kan SHAKYA Subhashsagar LI Lun-gui SUN xiao-dan School of Civil Engineering Southwest Jiaotong University MOE Key Laboratory of High-speed Railway Engineering Southwest Jiaotong University Road and Railway Engineering Research Institute Sichuan Key Laboratory of Aseismic Engineering and Technology

The frequency and extent of debris flows have increased tremendously due to the extreme weather and the Wenchuan earthquake on May 12, 2008. Previous studies focused on the debris flow from gullies damming the mountain streams. In this paper, an equation for the run-out distance of debris flow in the main river is proposed based on the dynamic equation of debris flow at different slopes given by Takahashi. By undertaking field investigations and flume experiments, a new calculation method of the volume of debris flow damming large river is obtained. Using the percolation theory and the renormalization group theory it was deduced that the large particles should comprise more than 50% for forming a stable debris flow dam. Hence, the criteria of damming large river by debris flow is presented in terms of run-out distance and grain composition which was then validated through the event of damming river by debris flow at Gaojia gully, the upper reaches of the Minjiang River, Sichuan, China, on July 3, 2011.

关键词： Debris flow Damming.large river Criteria Run-out distance Grain composition

Structural,Electronic,Optical and Thermodynamic Properties of Nanolaminated Boride Cr_4AlB_6

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Chinese Journal of Structural Chemistry 2018年第10期37卷 1572-1584页

作者： ZHANG Rui-Zhou cui Hong-ling LI xiao-Hong College of Physics and Engineering Henan University of Science and TechnologyLuoyang471003China Henan Key Laboratory of Photoelectric Energy Storage Materials and Applications Luoyang 471023China

Density functional calculations were used to investigate the structural,electronic,optical and thermal properties of Cr_4AlB_*** optimized lattice constants and atomic positions accord well with the experimental *** analysis of band structure and density of states confirms the metallic nature of Cr_4AlB_*** static dielectric constant e1（0） is about 128.0,and the maximum optical conductivity occurs at about 8.12 *** the photon energy range from 7.87 to 23.48 e V,Cr_4AlB_6 presents a metal reflective *** plasma resonance frequency wp of Cr_4AlB_6 is at the photon energy of 23.85 eV,and Cr_4AlB_6 will be transparent and change from metallic to dielectric response if the incident light has frequency greater than the plasma frequency of Cr_4AlB_*** properties including the primitive cell volume and thermal expansion,the bulk modulus and heat capacity Cv were further investigated with the increasing temperature and pressure by using the quasi-harmonic Debye model.

关键词： electronic structure optical property thermodynamic property band structure first-principles calculations

Activating transcription factor 5 regulates lipid metabolism in adipocytes

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Science Bulletin 2016年第23期61卷 1802-1809页

作者： Jing-Hui Jiang Yue Zhao Liu-ling xiao cui-Song Zhu Shu-Fen Li Xi Li Key Laboratory of Metabolic Molecular Medicine the Ministry of Education Department of Biochemistry and Molecular Biology Fudan University Basic Medical SchoolShanghai 200032 China Jiangsu Key Laboratory of Molecular Medicine School of Medicine Nanjing University Nanjing 210093 China Chongqing Medical University Chongqing 400016 China

Activating transcription factor 5(ATF5) is a member of the activating transcription factor/cA MP response element binding protein(ATF/CREB) family, and is highly expressed in liver and adipose tissue. Previous reports have shown that ATF5 promoted 3T3-L1 preadipocytes differentiation. In this study, we found that ATF5 was highly expressed in mature adipocytes, suggesting a potential role of ATF5 in mature adipocytes, which has not been reported previously. To understand the function of ATF5 in mature adipocytes, we knocked down the expression of ATF5 in 3T3-L1 mature adipocytes and observed decreased lipid droplets. Consistent with the in vitro experiment, the knockdown of ATF5 in white adipose tissue led to less adipose tissue and smaller adipocytes size. Further research revealed that the inhibition of ATF5 diminished the adipocytes size via the inhibition of fatty acid synthetase, stearyl coenzyme A desaturation enzyme 1, and the induction of carnitine palmitoyl transferase 1, one key enzyme of lipid metabolism. In addition, ATF5 knockdown in inguinal white adipose tissue improved whole body insulin *** work provides a new understanding of ATF5 function in mature adipocytes and a potential therapeutic target of diabetes.

关键词： Activating tra scription factor 5 Adipocytes Lipid metabolism.

Millimeter-sized few-layer graphene sheets with aligned channels for fast lithium-ion charging kinetics

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Journal of Energy Chemistry 2021年第4期30卷 62-69页

作者： Yu-Qi Zhou xiao-ling Dong Wen-cui Li Guang-Ping Hao Dong Yan An-Hui Lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina

Assembly of the top-down graphene units mostly results in 3D porous structure with randomly organized *** direct bottom-up synthesis of macroscopic 2D graphene sheets with organized pores are long sought in materials chemistry field,but rarely ***,we present a self-catalysisassisted bottom-up route usingL-glutamic acid and iron chloride as starting materials for the fabrication of the millimeter-sized few-layer graphene sheets with aligned porous channels parallel to the 2D *** amino-and carboxyl-functional groups inL-glutamic acid can coordinate with iron cations,thus allowing an atomic dispersion of iron *** pyrolysis thus initiated the growth of graphene catalyzed by in-situ generated iron nanoparticles,and a dynamic flow of iron nanoparticles eventually led to the formation of millimeter-sized few-layer graphene sheets with aligned channels(60-85 nm in diameter).Used as anodes in lithium-ion batteries,these graphene sheets showed a good rate capability(142 m A h g^(-1) at 2 A g^(-1))and high capacity retention of 93%at 2 A g^(-1) after 1200 *** analysis revealed that lithium ions storage was dominated by diffusion behavior and capacitive behavior together,in that graphene sheets with aligned channels could accelerate electron transfer and shorten lithium ions transport *** work provides a novel approach to prepare unique porous graphene materials with specific structure for energy storage.

关键词： Few-layer graphene Aligned channels Catalytic growth Lithium-ion batteries

A Hybrid Circular Queue Method for Iterative Stencil Computations on GPUs

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Journal of Computer Science & Technology 2012年第1期27卷 57-74页

作者： Yang Yang Hui-Min cui xiao-Bing Feng Jing-ling Xue State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China Graduate University of Chinese Academy of Sciences Beijing 100190China Programming Languages and Compilers Group School of Computer Science and Engineering University of New South WalesSydneyNSW 2052Australia

In this paper, we present a hybrid circular queue method that can significantly boost the performance of stencil computations on GPU by carefully balancing usage of registers and shared-memory. Unlike earlier methods that rely on circular queues predominantly implemented using indirectly addressable shared memory, our hybrid method exploits a new reuse pattern spanning across the multiple time steps in stencil computations so that circular queues can be implemented by both shared memory and registers effectively in a balanced manner. We describe a framework that automatically finds the best placement of data in registers and shared memory in order to maximize the performance of stencil computations. Validation using four different types of stencils on three different GPU platforms shows that our hybrid method achieves speedups up to 2.93X over methods that use circular queues implemented with shared-memory only.

关键词： stencil computation circular queue GPU occupancy register

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风疹减毒活疫苗的稳定性研究

中国生化药物杂志 2002年第1期23卷 30-32页

作者：梁勇陈怀恭石庆华邱晓玲崔焰兰州生物制品研究所甘肃兰州730046

目的考察风疹减毒活疫苗的稳定性和最佳保存条件。方法将风疹减毒活疫苗在 - 6 0℃、- 2 0℃、4℃和 37℃存放 ,在不同时间采用 2 4孔细胞板组织培养法进行风疹病毒滴度测定。结果 - 2 0℃或 - 6 0℃保存风疹减毒活疫苗比在 2℃～ 8℃... 详细信息

目的考察风疹减毒活疫苗的稳定性和最佳保存条件。方法将风疹减毒活疫苗在 - 6 0℃、- 2 0℃、4℃和 37℃存放 ,在不同时间采用 2 4孔细胞板组织培养法进行风疹病毒滴度测定。结果 - 2 0℃或 - 6 0℃保存风疹减毒活疫苗比在 2℃～ 8℃保存更稳定。

关键词：风疹减毒活疫苗稳定性病毒滴度风疹预防