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Semisolid die forging process,microstructures and properties of AZ31 magnesium alloy mobile telephone shells

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 665-670页

作者： Ren-guo Guan Li-qing Chen Fu-rong Cao zhan-yong Zhao yong Ren College of Materials and Metallurgy Northeastern University Shenyang 110004 China State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 China

A semisolid slurry of AZ31 magnesium alloy was prepared by vibrating wavelike sloping plate process,and the semisolid die forging process,microstructures,and properties of the magnesium alloy mobile telephone shell were *** semisolid forging process was performed on a YA32-315 four-column universal hydraulic *** microstructures were observed by optical microscopy,the hardness was analyzed with a model 450SVD Vickers hardometer,the mechanical properties was measured with a CMT5105 tensile test machine,and the fractograph of elongated specimens was observed by scanning electron microscopy （SEM）.The results reveal that with the increase of die forging force,the microstructures of the product become fine and dense.A lower preheating temperature and a longer dwell time are favorable to the formation of fine and dense *** optimum process conditions of preparing mobile telephone shells with excellent surface quality and microstructures are a die forging force of 2000 kN,a die preheating temperature of 250℃,and a dwell time of 240 *** solution treatment at 430℃ and aging at 220℃ for 8 h,the Vickers hardness is 61.7 and the ultimate tensile strength of the product is *** fractographs show the mixing mechanisms of quasi-cleavage fracture and ductile fracture.

关键词： magnesium alloys semisolid forging microstructure mechanical properties fracture

Redox-responsive polymer prodrug/AgNPs hybrid nanoparticles for drug delivery

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Chinese Chemical Letters 2018年第2期29卷 301-304页

作者： Liang Qiu Linfei Zhao Chengfen Xing yong zhan Institute of Biophysics Hebei University of Technology

A drug carrier system of the hybrid nanoparticles based on the redox-responsive P[（2-（（2-（（camptothecin）-oxy）ethyl）disulfanyl）ethylmethacrylate）-co-（2-（D-galactose）methylmethacryl-ate）]（P（MACPTS-co-MAGP）） and AgNPs is developed to deliver the anti-cancer drug camptothecin（CPT） and monitor the drug release by the recovery of the fluorescence of CPT. CPT is linked to the polymer sidechains via a redox-responsive disulfide bond, attaching on the surface of AgNPs and leading to the quenching of CPT fluorescence（＂off＂ state） due to the nanoparticle surface energy transfer（NSET） *** the exposure to glutathione（GSH）, the disulfide bond is cleaved to release CPT, resulting in the recovery of the fluorescence of CPT（＂on＂ state）. The system offers a platform to track the CPT delivery and releasing in real time

关键词： Redox-responsive Drug delivery system Hybrid nanoparticles NSET effect

Design method of pile-slab structure roadbed of ballastless track on soil subgrade

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Journal of Central South University 2013年第7期20卷 2072-2082页

作者： zhan yong-xiang YAO Hai-lin JIANG Guan-lu Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China State Key Laboratory of Geomechanics and Geotechnical Engineering (Institute of Rock and soil Mechanics Chinese Academy of Sciences) Wuhan 430071 China School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

Pile-slab structure roadbed is a new form of ballastless track for high speed railway. Due to lack of corresponding design code, based on the analysis of its structure characteristics and application requirements, it is proposed to carry out load effect combination according to ultimate limit state and serviceability limit state, and the most unfavorable combination of each state is chosen to carry through design calculation for pile-slab structure. Space model of pile-slab structure can be simplified as a plane flame model, by using the orthogonal test method, and the design parameter of pile-slab structure is optimized. Moreover, based on the engineering background of Suining-Chongqing high-speed railway, the dynamic deformation characteristics of pile-slab structure roadbed are further researched by carrying on the indoor dynamic model test. The test results show that the settlement after construction of subgrade satisfies the requirement of settlement control to build ballastless track on soil subgrade for high-speed railway. Slab structure plays the role of arch shell as load is transmitted from slab to pile, and the vertical dynamic stress of subgrade soil is approximately of ＂K＂ form distribution with the depth. The distribution of pile stress is closely related to soil characteristics, which has an upset triangle shape where the large dynamic stress is at the top. Pile compared with soil shares most dynamic stress. Pile structure expands the depth of the dynamic response of subgrade has limited effect on dynamic response. These results can provide subgrade. and improves the stress of subgrade soil, and the speed of train scientific basis for pile-slab structure roadbed used on soil

关键词： soil subgrade ballastless track pile-slab structure roadbed load combination dynamic model test

Effective Potential of a Two-State Model for Molecular Motor

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Communications in Theoretical Physics 2005年第2期43卷 377-381页

作者： HANYing-Rong ZHAOTong-Jun zhan-yong YANWei-Li SchoolofScience HebeiUniversityofTechnologyTianjin300130China SchoolofScience HebeiUniversityofTechnologyTianjin300130China／／SchoolofElectricalEngineeringHebeiUniversityofTechnologyTianjin300130China SchoolofElectricalEngineering HebeiUniversityofTechnologyTianjin300130China

We study force generation and motion of molecular motors using a simple two-state model in the *** and periodic potential is adopted to describe the interaction between motor proteins and filaments that are periodic and polar. The current and the slope of the effective potential as functions of the temperature and transition rates are calculated in the two-state model. The ratio of the slope of the effective potential to the current is also calculated. It is shown that the directed motion of motor proteins is relevant to the effective potential. The slope of the effective potential corresponds to an average force. The non-vanishing force therefore implies that detailed balance is broken in the process of transition between different states.

关键词： Brownian particle directed motion Fokker-Planck equation effective potential detailed balance

Domain Decomposition Method for a System of Quasivariational Inequalities

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 75-82页

作者： Shu-zi Zhou zhan-yong Zou Guang-hua Chen Department of Applied Mathematics Hunan University Changsha 410082 China School of Mathematics & Computational Science Guangdong University of Business Studies Guangzhou510320 China

We propose a domain decomposition method for a system of quasivariational inequalities related to the HJB equation. The monotone convergence of the algorithm is also established.

关键词： Domain decomposition method system of quasivariational inequalities HJB equation monotoneconvergence

A blind watermarking algorithm for 3D mesh models based on vertex curvature

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第5期15卷 351-362页

作者： yong-zhao zhan Yan-ting LI Xin-yu WANG Yi QIAN School of Computer Science and Communication Engineering Jiangsu University

We propose a robust blind watermarking algorithm for three-dimensional(3D)mesh models based on vertex curvature to maintain good robustness and improve visual masking in 3D mesh *** the embedding process,by using the local window of vertex,the root mean square curvature is calculated for every vertex of the 3D mesh model and an ordered set of fluctuation values is *** to the ordered fluctuation values,the vertices are separated into *** each bin the fluctuation values are ***,the mean of the root mean square curvature fluctuation values of the vertices in each bin is modulated to embed watermark *** watermark detection,the algorithm uses a blind watermark extraction technique to extract the watermark *** experimental results show that the algorithm has a very good performance for visual masking of the embedded model and that it can resist a variety of common attacks such as vertex rearrangement,rotation,translating,uniform scaling,noise,smoothing,quantization,and simplification.

关键词： Three-dimensional mesh model Visual masking Root mean square curvature Blind watermarking Attack resisting

Effect of electrochemical etching current on prepared perforated silicon structures for neutron detectors

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Frontiers of Materials Science 2013年第1期7卷 96-101页

作者： Xiao-Qiang FAN yong JIANG Chang-yong zhan Yu ZOU Jian-Chun WU Ning-Kang HUANG Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China Key Laboratory of Radiation Physics and Technology (Ministry of Education) Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China

Neutron detector based on perforated silicon structures backfilled with neutron converting materials could be operated at a low voltage and improves the detection efficiency of thermal neutron. It is found that the intrinsic detection efficiency of thermal neutron is affected by a lot of factors such as the geometry, size, and depth of the perforation and so on. In this study, the perforated silicon was prepared by electrochemical etching. Effect of etching current on geometry, size, and depth of the perforated silicon structures for neutron detectors was also reported.

关键词： neutron detector silicon electrochemical etching current

Permeation mechanism of a two-state potassium channel

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Frontiers in Biology 2007年第1期2卷 108-113页

作者： WANG Xiangqun ZHAO Tongjun SONG Yang zhan yong School of Science Hebei University of TechnologyTianjin 300130China

A two-state hopping model was proposed to study the permeation of ion *** Nernst equation in equilibrium and the Michaelis-Menten relation in steady state were derived from the two-state kinetic *** currentvoltage relationship obtained in the symmetrical solutions case was linear when the applied potential was less than 100 mV,which met Ohm’s *** conductance-concentration relationship exhibited the saturation ***,the characteristic time reaching the steady state of the KcsA channel was also discussed.

关键词： potassium channel selectivity filter master equation

Speaker-independent speech emotion recognition by fusion of functional and accompanying paralanguage features

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第7期14卷 573-582页

作者： Qi-rong MAO Xiao-lei ZHAO Zheng-wei HUANG yong-zhao zhan Department of Computer Science and Communication Engineering Jiangsu University

Functional paralanguage includes considerable emotion information, and it is insensitive to speaker changes. To improve the emotion recognition accuracy under the condition of speaker-independence, a fusion method combining the functional paralanguage features with the accompanying paralanguage features is proposed for the speaker-independent speech emotion recognition. Using this method, the functional paralanguages, such as laughter, cry, and sigh, are used to assist speech emotion recognition. The contributions of our work are threefold. First, one emotional speech database including six kinds of functional paralanguage and six typical emotions were recorded by our research group. Second, the functional paralanguage is put forward to recognize the speech emotions combined with the accompanying paralanguage features. Third, a fusion algorithm based on confidences and probabilities is proposed to combine the functional paralanguage features with the accompanying paralanguage features for speech emotion recognition. We evaluate the usefulness of the functional paralanguage features and the fusion algorithm in terms of precision, recall, and F1-measurement on the emotional speech database recorded by our research group. The overall recognition accuracy achieved for six emotions is over 67% in the speaker-independent condition using the functional paralanguage features.

关键词： Speech emotion recognition Speaker-independent Functional paralanguage Fusion algorithm Recognition accuracy