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SYNTHESIS OF NATURAL RUBBER-g-MALEIC ANHYDRIDE AND ITS USE AS A COMPATIBILIZER IN NATURAL RUBBER/SHORT NYLON FIBER COMPOSITES

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Chinese Journal of Polymer Science 2013年第8期31卷 1127-1138页

作者：董智贤 Ming-xian Liu 贾德民 Yan-hao zhou College of Materials Science and Engineering South China University of Technology School of Materials and Energy Guangdong University of Technology Guangzhou Higher Education Mega Center

Natural rubber grafted maleic anhydride （NR-g-MAH） was synthesized by mixing maleic anhydride （MAH） and natural rubber （NR） in solid state in a torque rheometer using dicurnyl peroxide （DCP） as initiator. Then the self-prepared NR-g-MAH was used as a compatibilizer in the natural rubber/short nylon fiber composites. Both the fimctionalization of NR with MAH and the reaction between the modified rubber and the nylon fiber were confirmed by Fourier transform infrared spectroscopy （FTIR）. Composites with different nylon short fiber loadings （0, 5, 10, 15 and 20 phr） were compounded on a two-roll mill, and the effects of the NR-g-MAH on the tensile and thermal properties, fiber-rubber interaction, as well as the morphology of the natural rubber/short nylon fiber composites were investigated. At equal fiber loading, the NR-g-MAH compatibilized NR/short nylon fiber composites showed improved tensile properties, especially the tensile modulus at 100% strain which was about 1.5 times that of the corresponding un-compatibilized ones. The equilibrium swelling tests proved that the incorporation of NR-g-MAH increased the interaction between the nylon fibers and the NR matrix. The crosslink density measured with NMR techniques showed that the NR-g-MAH compatiblized composites had lower total crosslink density. The glass transition temperatures of the compatibilized composites were about 1 K higher than that of the corresponding un-compabilized ones. Morphology analysis of the NR/short nylon fiber composites confirmed NR-g-MAH improved interfacial bonding between the NR matrix and the nylon fibers. All these results signified that the NR-g-MAH could act as a good compatilizer of NR/short nylon fiber composites and had a potential for wide use considering its easy to be prepared and compounded with the composites.

关键词： Natural rubber Maleic anhydride graft Natural rubber/short nylon fiber composite.

Facile synthesis of Zn（Ⅱ）-doped g-C3N4 and their enhanced photocatalytic activity under visible light irradiation

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Rare Metals 2019年第5期38卷 459-467页

作者： Zhao-Tian Wang Jun-Li Xu Hui zhou Xia Zhang College of Science Northeastern University

Zn(Ⅱ)-doped graphitic carbon nitride(g-C3N4)with high photodegradation activity was prepared by one facile *** morphology and structure of the prepared Zn(Ⅱ)-doped g-C3N4 were investigated,and the results showed that Zn(Ⅱ)could self-disperse during the pyrolysis process and Zn–N bond was formed between g-C3N4 and *** dope of Zn(Ⅱ)influenced the structure of *** performance of photocatalytic activity of Zn(Ⅱ)-doped g-C3 N4 series indicated that the doped g-C3N4 with a small quantity of Zn(0.10 wt%)exhibits the best photocatalytic *** photodegradation activity for methyl orange was 2 times higher than that of pure ***,the photocatalytic activity decreased with the further increased content of Zn,which may be attributed to the structure change of g-C3N4 and the interaction of Zn–N bond between Zn and ***,Zn(Ⅱ)-doped g-C3N4 showed good recycling photocatalytic stability.

关键词： Zn(Ⅱ)dope g-C3N4 Visible light irradiation Photodegradation Photocatalytic stability

Influence of wall slip on the hydrodynamic behavior of a two-dimensional slider bearing

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Acta Mechanica Sinica 2007年第6期23卷 655-661页

作者： g. J. Ma C. W. Wu P. zhou State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China

In the present paper, a multi-linearity method is used to address the nonlinear slip control equation for the hydrodynamic analysis of a two-dimensional （2-D） slip gap flow. Numerical analysis of a finite length slider bearing with wall slip shows that the surface limiting shear stress exerts complicated influences on the hydrodynamic behavior of the gap flow. If the slip occurs at either the stationary surface or the moving surface （especially at the stationary surface）, there is a transition point in the initial limiting shear stress for the proportional coefficient to affect the hydrodynamic load support in two opposite ways： it increases the hydrodynamic load support at higher initial limiting shear stresses, but decreases the hydrodynamic load support at lower initial limiting shear stresses. If the slip occurs at the moving surface only, no fluid pressure is generated in the case of null initial limiting shear stress. If the slip occurs at both the surfaces with the same slip property, the hydrodynamic load support goes off after a critical sliding speed is reached. A small initial limiting shear stress and a small proportionality coefficient always give rise to a low friction drag.

关键词： Wall slip Slider beating Multi-linearity method Quadratic programming

Primary malignant tumor of the small intestine

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World Journal of gastroenterology 1999年第3期5卷 273-276页

作者： zhou ZW Wan DS Chen g Chen YB Pan ZZ Sun Yat Sen Univ Med Sci Dept Abdominal Surg Ctr Canc Guangzhou 510060 Guangdong Prov Peoples R China

INTRODUCTIONPrimary malignant tumors of the small intestine are easy to be misdiagnosed because of its low morbidity, nonspecific clinical manifestations and the limited examination methods. Most cases are already in advanced stage at the time of diagnosis, so therapeutic result is very poor. In order to have a better understanding of the clinical characteristics of malignant tumor of the small intestine, an analysis was made for the diagnosis, treatment and prognosis—influencing factors of 75 cases with their diagnoses confirmed by pathological examination from 1964 to August 1995 in our hospital, so as to improve their early diagnosis, timely treatment and therapeutic effect.

关键词： Primary malignant tumor of the small intestine Wang CTX

EFFECT OF PREDEFORMATION MANNER ON SEMI-SOLID STRUCTURE OF AZ61 MAgNESIUM ALLOY IN SIMA PROCESS

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 197-204页

作者： g.P. Chen T.R. zhou H. Yan School of Mechanical and Electrical Engineering Nanchang University Nanchang 330000 China School of Mechanical Engineering Hunan Industrial University Zhuzhou 412008 China

The effect of predeformation manner, predeformation ratio and isothermal heat-treat parameter on the non-dendrite structure of AZ61 magnesium alloy in SIMA process was studied. Under coequal heat-treat condition, the impact of the hot upsetting pre- deformation on semi-solid microstructure in SIMA process was compared with that of the cold compressive predeformation. The results indicate that non-dendrite microstructure in AZ61 magnesium alloy billets can be obtained by hot or cold upsetting predeformation in SIMA process, although their mechanisms of evolution are different. Increasing hot or cold upsetting predeformation ratio can enhance the effect and quality of the non-dendrite microstructure formed before storage energy up to saturation, but the proper isothermal temperature and holding time should be selected.

关键词： AZ61 magnesium alloy Strain-induced melt activated (SIMA) Hot and cold upsetting Predeformation Non-dendrite structure

Traffic-load prediction based on echo state network improved by Bayesian theory in 10g-EPON

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The Journal of China Universities of Posts and Telecommunications 2015年第2期22卷 69-73页

作者： Bai Huifeng Zhao Xianlong zhou Hongfeng Zhang Likun Beijing NARI Smart Chip Microelectronics Company Limited Translation Department

With the evolution of 10-gigabit Ethemet passive optical network （10g-EPON）, the traffic-load prediction ability is necessary to support soaring services traffic with diversified characteristics and requirements. As a strong candidate to be used for the traffic-load prediction, the echo state network （ESN） may face the pseudo-regression problem and need to be improved for the better traffic-load prediction. To overcome this problem, this paper proposes an ESN based traffic-load prediction scheme using Bayesian theory in 10g-EPON for future-proof. In this proposed approach, Bayesian probability is introduced into the ESN and is used to improve the performance of ESN. According to the architecture between optical line terminal （OLT） and optical network units （ONU） in 10g-EPON, an ESN based on the Bayesian theory （B-ESN） is realized and the B-ESN based traffic load prediction scheme is also developed in OLT. Experiment results show that the proposed scheme can greatly better the accuracy of traffic-load prediction with lower complex degree.

关键词： 10-gigabit passive optical network traffic-load prediction ESN Bayesian theory

Detection of quantization index modulation steganography in g.723.1 bit stream based on quantization index sequence analysis

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第8期13卷 624-634页

作者： Song-bin LI Huai-zhou TAO Yong-feng HUANg Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Tsinghua National Laboratory for Information Science and Technology Beijing 100084China

This paper presents a method to detect the quantization index modulation(QIM) steganography in g.723.1 bit *** show that the distribution of each quantization index(codeword) in the quantization index sequence has unbalanced and correlated *** present the designs of statistical models to extract the quantitative feature vectors of these *** the extracted vectors with the support vector machine,we build the classifier for detecting the QIM steganography in g.723.1 bit *** experiment shows that the method has far better performance than the existing blind detection method which extracts the feature vector in an uncompressed *** recall and precision of our method are all more than 90% even for a compressed bit stream duration as low as 3.6 s.

关键词： Steganalysis Quantization index modulation (QIM) g.723.1 Codeword distribution characteristics

Exploring the Road to 6g: ABC-Foundation for Intelligent Mobile Networks

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China Communications 2020年第6期17卷 51-67页

作者： Jinkang Zhu Ming Zhao Sihai Zhang Wuyang zhou CAS Key Laboratory of Wireless-Optical Communications University of Science and Technology of ChinaHefei 230022China

The 5 th generation(5 g)mobile networks has been put into services across a number of markets,which aims at providing subscribers with high bit rates,low latency,high capacity,many new services and vertical *** the research and development on 6 g have been put on the *** demands and characteristics of future 6 g,artificial intelligence(A),big data(B)and cloud computing(C)will play indispensable roles in achieving the highest efficiency and the largest ***,the initials of these three aspects remind us the significance of vitamin ABC to human *** this article we specifically expound on the three elements of ABC and relationships in *** analyze the basic characteristics of wireless big data(WBD)and the corresponding technical action in A and C,which are the high dimensional feature and spatial separation,the predictive ability,and the characteristics of *** on the abilities of WBD,a new learning approach for wireless AI called knowledge+data-driven deep learning(KD-DL)method,and a layered computing architecture of mobile network integrating cloud/edge/terminal computing,is proposed,and their achievable efficiency is *** progress will be conducive to the development of future 6 g.

关键词： 6g Artificial intelligence Wireless big data Cloud computing Knowledge+data driven deep learning layered computing layered network

Influence of inflow discharge and bed erodibility on outburst flood of landslide dam

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Journal of Mountain Science 2019年第4期16卷 778-792页

作者： zhou Ming-jun zhou gordon g.D. CUI Kahlil Fredrick E. SONg Dong-ri LU Xue-qiang Key Laboratory of Mountain hazards and Earth Surface Process/Institute of Mountain hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Accurate prediction of the hydrographs of outburst floods induced by landslide dam overtopping failure is necessary for hazard prevention and mitigation. In this study, flume model tests on the breaching of landslide dams were conducted. Unconsolidated soil materials with wide grain size distributions were used to construct the dam. The effects of different upstream inflow discharges and downstream bed soil erosion on the outburst peak discharge were investigated. Experimental results reveal that the whole hydrodynamic process of landslide dam breaching can be divided into three stages as defined by clear inflection points and peak discharges. The larger the inflow discharge, the shorter the time it takes to reach the peak discharge, and the larger the outburst flood peak discharge. The scale of the outburst floods was found to be amplified by the presence of an erodible bed located downstream of the landslide dam. This amplification decreases with the increase of upstream inflow. In addition, the results show that the existence of an erodible bed increases the density of the outburst flow, increasing its probability of transforming from a sediment flow to a debris flow.

关键词： Landslide dam Inflow discharge Erodible bed Outburst flood