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Tungsten 2024年第3期6卷 504-521页

作者： Shuang Ma Qing-Ling Ruan xue-cheng liu Gui-Jun Zhu Die Yuan Ling-Qiao Hu Yu-Mei Huang Xing-Xing Gu Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and Resources Chongqing Technology and Business University National Research Base of Intelligent Manufacturing Service Chongqing Technology and Business University

Lithium-sulfur(Li-S) batteries have attracted much attention and developed rapidly in recent years due to their high energy density,low cost,and ***,its commercialization process still encounters various *** them,the sulfur cathode is easy to dissolve and shuttle,resulting in the loss of active substances and the severe growth of lithium anode dendrites,which is one of the biggest *** the redox conversion kinetics of sulfur cathode is expected to fundamentally alleviate the shuttle phenomenon of poly ***,this paper reviews the effects of metal nanoparticles to metal nanoclusters to metal single-atom catalysts on improving the redox of Li-S batteries,to let researchers better understand the size effect on the kinetics of sulfur cathodes in Li-S batteries,which will provide important guidance for the future large-scale commercialization of Li-S batteries.

关键词： Lithium–sulfur batteries Metal nanoparticles Metal nanoclusters Metal single atoms Size effects

The research of DPA attacks against AES implementations

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 101-106页

作者： HAN Yu ZOU xue-cheng liu Zheng-lin CHEN Yi-cheng Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

This article examines vulnerabilities to power analysis attacks between software and hardware implementations of cryptographic algorithms. Representative platforms including an Atmel 89S8252 8-bit processor and a 0.25 um 1.8 v standard cell circuit are proposed to implement the advance encryption standard （AES）. A simulation-based experimental environment is built to acquire power data, and single-bit differential power analysis （DPA）, and multi-bit DPA and correlation power analysis （CPA） attacks are conducted on two implementations respectively. The experimental results show that the hardware implementation has less data-dependent power leakages to resist power attacks. Furthermore, an improved DPA approach is proposed. It adopts hamming distance of intermediate results as power model and arranges plaintext inputs to differentiate power traces to the maximal probability. Compared with the original power attacks, our improved DPA performs a successful attack on AES hardware implementations with acceptable power measurements and fewer computations.

关键词： AES implementation side-channel leakage DPA CPA power model power trace

Dynamic inhomogeneous S-Boxes design for efficient AES masking mechanisms

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 72-76页

作者： CHEN Yi-cheng ZOU xue-cheng liu Zheng-lin CHEN Xiao-fei HAN Yu Research Center for VLSI and Systems Huazhong University of Science andTechnology Wuhan 430074 China

It is an important challenge to implement a lowcost power analysis immune advanced encryption standard （AES） circuit. The previous study proves that substitution boxes （S-Boxes） in AES are prone to being attacked, and hard to mask for its non-linear characteristic. Besides, large amounts of circuit resources in chips and power consumption are spent in protecting S-Boxes against power analysis. Thus, a novel power analysis immune scheme is proposed, which divides the data-path of AES into two parts： inhomogeneous S-Boxes instead of fixed S-Boxes are selected randomly to disturb power and logic delay in the non-linear module; at the same time, the general masking strategy is applied in the linear part of AES. This improved AES circuit was synthesized with united microelectronics corporation （UMC） 0.25 μm 1.8 V complementary metal-oxide-semiconductor （CMOS） standard cell library, and correlation power analysis experiments were executed. The results demonstrate that this secure AES implementation has very low hardware cost and can enhance the AES security effectually against power analysis.

关键词： AES S-Boxes power analysis correlation poweranalysis (CPA)

Low-power clock-less hardware implementation of the rijndael S-box for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 104-109页

作者： ZENG Yong-hong ZOU xue-cheng liu Zheng-lin LEI Jian-ming Research Center for VLSI and Systems Department of Electronic Scienceand Technology Huazhong University of Science and TechnologyWuhan 430074 China

The recent development of microelectronics techniques and advances in wireless communications have made it feasible to design low-cost, low-power, multifunctional and intelligent sensor nodes for wireless sensor networks （WSN）. The design challenges for an efficient WSN mainly lie in two issues： power and security. The Rijindael algorithm is a candidate algorithm for encrypting data in WSN. The SubByte （S-box） transformation is the main building block of the Rijindael algorithm. It dominates the hardware complexity and power consumption of the Rijindael cryptographic engine. This article proposes a clock-less hardware implementation of the S-box. In this S-box, l） The composite field arithmetic in GF（（2^4））2 was used to implement the compact datapath circuit; 2） A high-efficiency latch controller was attained by utilizing the four-phase micropipeline. The presented hardware circuit is an application specific integrated circuit （ASIC） on 0.25 μm complementary mental oxide semiconductor （CMOS） process using three metal layers. The layout simulation results show that the proposed S-box offers low-power consumption and high speed with moderate area penalty. This study also proves that the clock-less design methodology can implement high- performance cryptographic intellectual property （IP） core for the wireless sensor node chips.

关键词： WSN rijindael algorithm S-box clock-less composite field arithmetic four-phase micropipeline

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi liu xue-Dong Li Liang cheng Li liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

The effect of shoe type on gait in forefoot strike runners during a 50-km run

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Journal of Sport and Health Science 2014年第2期3卷 122-130,153+157页

作者： Mark E.Kasmer Nicholas C.Ketchum xue-cheng liu Department of Physical Medicine and Rehabilitation Medical College of Wisconsin Department of Orthopedic Surgery Medical College of Wisconsin

Purpose:To observe the relative change in foot-strike pattern,pressure characteristics,surface electromyography(sEMG) recordings,and stride characteristics in forefoot strike runners wearing both minimalist and traditional shoes during a 50-km ***:Four experienced minimalist runners were enrolled in this *** runner ran a 50-km simulated run in both minimalist shoes and traditional *** data,sEMG recordings,and limited 3D motion capture data were collected during the initial 0.8 km and final 0.8 km for each ***:Three runners in the traditional shoe type condition and one runner in the minimalist shoe type condition demonstrated a more posterior initial contact area(midfoot strike(MFS) pattern) after the 50-km *** was supported by increased activity of the tibialis anterior in the pre-contaet phase(as per root mean square(RMS) values).In addition,in both pre- and post-run conditions,there were increased peak pressures in the minimalist shoe type,specifically in the medial *** fatigue as defined by a decreased median frequency observed in isometric,constant force contractions did not correspond with our hypothesis in relation to the observed foot strike change ***,step rate increased and step length decreased after the 50-km run in both shoe type ***:More runners adopted a more posterior initial contact area after the 50-km run in the traditional shoe type than in the minimalist shoe *** runners who adopted a more posterior initial contact area were more closely associated with an increased median frequency of the medial gastrocnemius,which suggests there may be a change in motor unit recruitment pattern during long-distance,sustained velocity *** increased peak pressures observed in the medial forefoot in the minimalist shoe type may predispose to metatarsal stress fractures in the setting of improper training.

关键词： Endurance Fatigue Foot-strike pattern Running Surface electromyography(sEMG)

Vision-based docking system for an aromatic-hydrocarbon-inspired reconfigurable robot

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Science China(Technological Sciences) 2024年第6期67卷 1798-1816页

作者： XING FangYi XU cheng liu JinGuo xue ZhiHui State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyang110158China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China University of Chinese Academy of Sciences Beijing100049China

Aromatic hydrocarbons generally refer to compounds containing benzene *** types of isomers can be formed by replacing hydrogen atoms on the benzene *** this paper,an aromatic-hydrocarbon-inspired modular robot(AHIMR)is *** robot can be reassembled into different configurations suitable for various task requirements.A vision-based docking system is designed for the *** system primarily consists of two stages:a remote guidance stage and a precise docking *** the remote guidance stage,an object module is identified using an illumination adaptive target recognition algorithm,and then the active module moves to the docking area through communication with *** the precise docking stage,the active module calculates the relative pose with the object module using a perspective-n-point method and dynamically adjusts its posture to *** this process,a Kalman filter is used to reduce target occlusion and jitter *** addition,the docking system feasibility is verified via several simulation *** module docking accuracy is controlled within 0.01 m,which meets the reconfiguration task requirements of the *** the AHIMR submodule docking experiment,the active module accurately moves to the expected position with a docking success rate of 95%.

关键词： modular robot reconfiguration aromatic hydrocarbon autonomous docking visual identification

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo liu Shu-sen cheng Yu-qing xue Xiao-man cheng Zhao liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Morphological characteristics and evolution model of slope units along loess gully cross section

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Frontiers of Earth Science 2024年第1期18卷 17-29页

作者： Lulu liu Fayuan LI xue YANG Jianhua cheng School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Key Laboratory of Virtual Geographic Environment(Ministry of Education) Nanjing Normal UniversityNanjing 210023China

Gully morphology is an important part of loess landform *** with gully development,the variation of its cross section is the most significant,and it can intuitively reflect the characteristics of the lateral widening of the gully ***,in-depth research of the variation of the cross-sectional morphology of the gully is helpful to understanding the development process of the loess *** on the DEMs(Digital Elevation Model)of nine periods of an indoor simulated loess small watershed,this paper studies the evolution model of a complete branch ditch in the watershed using the digital terrain analysis theory and *** show that with the development of the gully,the average gradient of the gully slope continuously decreases,and the slope morphology is mostly a concave slope along the slope *** degree of downward concave first increases and then gradually tends to be *** gully erosion mode is gradually transformed from downward cutting erosion to lateral *** more mature the gully development,the lower the depth of gully bottom cutting is compared with the width of gully ***,the surface cutting depth tends to be stable and the slope is ***,the transformation law of the slope morphology of the gully cross section with the development of the gully is studied,and the prediction model of the transformation of the slope morphology of the gully cross section is established by using the Markov *** Markov model can better reflect the dynamic change of the slope morphology of the gully cross section,which is of great significance to revealing the external performance and internal mechanism of the gully morphology.

关键词： gully cross section slope morphology Markov chain digital elevation model

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng liu Zhen-xing Xing Gong-jin cheng xue-yong Ding Xiang-xin xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure