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China Communications 2016年第4期13卷 1-13页

作者： wang jihong SHI Wenxiao College of Communication Engineering Jilin University

Capacity reduction is a major problem faced by wireless mesh networks. An efficient way to alleviate this problem is proper channel assignment. Current end-toend channel assignment schemes usually focus on the case where channels in distinct frequency bands are assigned to mesh access and backbone, but actually backbone network and access network can use the same IEEE 802.11 technology. Besides, these channel assignment schemes only utilize orthogonal channels to perform channel assignment, and the resulting network interference dramatically degrades network performance. Moreover, Internet-oriented traffic is considered only, and peerto-peer traffic is omitted, or vice versa. The traffic type does not match the practical network. In this paper, we explore how to exploit partially overlapped channels to perform endto-end channel assignment in order to achieve effective end-to-end flow transmissions. The proposed flow-based end-to-end channel assignment schemes can conquer the limitations aforementioned. Simulations reveal that loadaware channel assignment can be applied to networks with stable traffic load, and it can achieve near-optimal performance; Traffic-irrelevant channel assignment is suitable for networks with frequent change of traffic load,and it can achieve good balance between performance and overhead. Also, partially overlapped channels' capability of improving network performance is situation-dependent, they should be used carefully.

关键词： channel assignment: end-to-end partially overlapped channels load-aware traffic-irrelevant

Microstructure of nano precursors of La-Mg hydrogen storage alloy synthesized by sol-gel technology at different pH values

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Rare Metals 2012年第5期31卷 466-469页

作者： wang Dahui XIA jihong ZHANG Sha Key Laboratory of Non-ferrous Metal Alloys and Processing of Ministry of Education Lanzhou University of Science and Technology Lanzhou 730050 China

Sol-gel technology was employed to synthesize nanosized precursors of La-Mg hydrogen storage alloy at different pH values (0.5, 1.5, 8.0 and 9.0) of reaction solution. The effect of pH value on microstructure of the nano precursors of La-Mg hydrogen storage alloy was studied by infrared radiation (IR), thermo-gravimetric and differential thermal analysis (TG/DTA), X-ray diffraction analyzer (XRD) and transmission electron microscopy (TEM). IR results indicate that the chelating agent, citric acid, is not fully ionized, and carboxyl groups are not entirely used to complex metal ions in acidic solutions. The efficiency of complexing metal ions is enhanced in basic solutions. TG/DTA results show that the combustion may take place with low rate of the flame propagation that causes the longer combustion time when pH<1.5. On the contrary, the dry gel synthesized in basic solution combusts at low ignition temperature and combustion reaction is violent; it is easy to form fine particles. XRD and TEM results reveal that the precursor powders are mainly two-phase mixture of La 2 O 3 and MgO. The morphology of the particles is almost flake with the size of ~30 nm when pH is 8.0.

关键词： pH value microstructure nano precursors sol-gel technology

SIMULATION OF HOLE FLANGING PROCESS ON HEAVY CYLINDERS AND PARAMETER OPTIMIZATION

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 243-245页

作者： LIU Jiansheng wang Bing TIAN jihong College of Materials Science ＆ Engineering Taiyuan University of Science and TechnologyTaiyuan 030024 China

The forming mechanism of hole flanging on a thick-wall heavy cylinder forging is simulated by DEFORM3D. The cylinder is 4 390 mm in diameter and 390 mm in thickness. The results show that the compound deformation with bending and expanding happens in the process of hole flanging. The diameter of pre-hole of the workpiece is one of the key parameters in the process of hole flanging. The optimal diameter is obtained for reverse-conical hole of average diameter 40 mm by simulation of hole flanging process on 5 pre-holes with different diameters and 3 pre-holes with different shapes. The results can provide the scientific base for engineering application of the process.

关键词： Hole flanging process Thick-wall cylinder Numerical simulation Pre-hole

On Channel Assignment for Multicast in Multi-Radio Multi-Channel Wireless Mesh Networks:A Survey

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China Communications 2015年第1期12卷 122-135页

作者： wang jihong SHI Wenxiao JIN Feng College of Communication Engineering Jilin University

The major challenge faced by wireless mesh networks is the capacity reduction caused by interference,and interference can be reduced or even eliminated through appropriate channel *** article presents a comprehensive survey of channel assignment schemes for multicast in multi-radio multi-channel wireless mesh *** analyze the state-of-the-art channel assignment schemes for multicast and provide comprehensive taxonomy of the latest *** general,we classify the channel assignment schemes for multicast into two types,that is,sequential multicast routing and channel assignment(SMRCA)and joint multicast routing and channel assignment(JMRCA).Detailed review of channel assignment schemes in each category is *** future research directions and corresponding solutions are also explored to motivate research interests in the field of channel assignment for multicast in wireless mesh networks.

关键词： multicast channel assignment interference partially overlapped channels

Anisotropy of Bi_(2)Sr_(2)CaCu_(2)O_(y) Superconducting Single Crystals Under High Pressure

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Chinese Physics Letters 1991年第1期8卷 29-32页

作者： LIU Zhenxing ZHENG Dongning YAN Yifeng wang jihong wang Lijun ZHAO Zhongxian Institute of Physics Academia SinicaBeijing 100080

It is shown that there exists the anisortropic nature of pressure dependence for the superconducting transition temperature and resistivity in Bi_(2)Sr_(2)CaCu_(2)O_(y) single *** maximum superconducting critical temperature and the minimum resistance along a-b plane under about 8kbar have been observed,no obvtous structure phase transition was observed at room temperature under pressure,and there is not the same behaviour along the c axis up to 13kba.r.A slight difference between the rates dT_(c)/dP along a-6 plane and c axis was also *** anisotropy may have close relation to the coupling between layers.

关键词： resistance plane Crystal

Lidar observation campaigns on diurnal variations of the sodium layer in Beijing and Wuhan, China

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Science China Earth Sciences 2015年第8期58卷 1377-1386页

作者： GONG ShaoHua YANG GuoTao CHENG XueWu GONG Shun Sheng XU JiYao LI FaQuan GONG Wei wang jihong School of Physics and Electronics Engineering Hainan Normal University State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Laboratory of Optoelectronics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

Based on observations from daytime lidars in eastern China,diurnal cycles of the sodium layer over Wuhan(30.5°N,114.6°E)and Beijing(40.5°N,116°E)are *** variations of Na density,root mean square(RMS)layer width,and centroid height of the sodium layer are *** reveal that the large diurnal cycles of the sodium layer are controlled mainly by 24-hr oscillations at the two observation *** diurnal variation of the sodium layer over Wuhan was modulated mainly by tidal perturbations during the lidar observation ***,the diurnal variation over Beijing was controlled principally by photoionization and photochemistry effects during another campaign,and there was little evidence of direct tidal *** comparisons suggest that the diurnal variation of the sodium layer perhaps has obvious regional characteristics across *** variation can be either controlled mainly by tidal perturbations or by photoionization and photochemistry effects in different seasons.

关键词： daytime lidar diurnal variations of the sodium layer photochemistry effects tidal perturbations

Application of surface plasmon resonance in screening adsorbents and explaining adsorption phenomena using model polymers

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Chinese Science Bulletin 2010年第32期55卷 3644-3647页

作者： FENG Jing FU LiXue LI jihong wang Wei YUAN Zhi Key Laboratory of Functional Polymer Materials Ministry of Education Institute of Polymer Chemistry Nankai University Tianjin 300071 China

A surface plasmon resonance (SPR) technique was developed as an online screening method to identify effective adsorbents for the peptide NH2-Cys-Thr-Trp-Trp-COOH (CW-4). To validate the SPR technique, several linear polymers containing amino acid residues were synthesized as models of their corresponding adsorbents. SPR screening of all the linear polymers demonstrated that the linear polymer containing phenylalanine residues (PPhe) exhibited the highest affinity for CW-4 among the polymers tested. In accordance with the screening results from SPR, the adsorbent containing phenylalanine (APhe) exhibited the highest adsorption capacity for CW-4. An interesting observation was that the amounts of CW-4 adsorbed on 3 adsorbents were quite small, even though both SPR and isothermal titration calorimetry (ITC) experiments indicated the presence of interactions between CW-4 and the three polymers. A kinetic analysis performed using SPR technology suggested such a phenomenon was ascribed to the poor stability of the CW-4/polymer complexes; that is, CW-4 associates with the polymers quickly, but it also dissociated quickly. The combined results suggested that SPR was a promising tool to identify the optimal adsorbent for peptides, analyze the interactions contributing to adsorption and explain adsorption phenomena using polymer models.

关键词：表面等离子体共振模型聚合物共振技术吸附现象筛选方法吸附剂战略石油储备线性聚合物

Anti-oxidative and immunological role of Cyclocarya paliurus polysaccharide on the liver injury of diabetic rats

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Journal of Traditional Chinese Medicine 2024年第6期44卷 1146-1152页

作者： XIA Xichao XUE Shipeng SONG Guoying LI Bin wang Huiping QIU Ju wang jihong LIU Qingchun MA Yuhong OUYANG Jingfeng Nursing College Pingdingshan UniversityPingdingshan 467000China Basic Medicine College of Nanyang Medical University Nanyang 473041China Beijing Key Laboratory of Traditional Chinese Medicine Basic Research on Prevention and Treatment for Major Diseases Experimental Research CenterChina Academy of Chinese Medical SciencesBeijing 100700China

OBJECTIVE: To investigate the effects of Cyclocarya paliurus(C. paliurus) polysaccharide on the liver injury of diabetic rats. METHODS: Rats were divided into 6 groups, including normal group, model group, control group, low-dose group of C. paliurus polysaccharide treatment, middledose group of C. paliurus polysaccharide treatment and high-dose group of C. paliurus polysaccharide treatment. Histological analysis of liver was analyzed using hematoxilin and eosin. Levels of plasma biological parameters and anti-oxidative enzymes were determined by spectrophotometry. Nuclear factor kappa-B-p65(NF-κB p65), tumor necrosis factor-α(TNF-α), interleukins 6(IL-6), IL-1β were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Compared with that of model group, the glucose level of plasma decreased 62.32%(P < 0.01), but glycogen and insulin level increased 1.51 times and 1.27 times in the high-dose group of C. paliurus polysaccharide treatment, respectively. Plasma alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP) level decreased 47.47%(P < 0.05), 43.65%(P < 0.05) and 50.51%(P < 0.05) in the high-dose group of C. paliurus polysaccharide treatment, respectively. Superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase level increased 1.16 times(P < 0.01), 71.28%(P < 0.05), 1.29 times(P < 0.01) and 87.46%(P < 0.05) in the high-dose group of C. paliurus polysaccharide treatment, respectively. Enzyme activities of NF-κB, TNF-α, IL-1β and IL-6 were decreased 39.29%(P < 0.05), 51.11%(P < 0.05), 37.42%(P < 0.05) and 36.50%(P < 0.05), respectively. CONCLUSIONS: Administration of C. paliurus polysaccharide may play a protecting role for liver injury of diabetic rats through lowering glucose, ALT, AST, ALP level, increasing glycogen and insulin level, enhancing the anti-oxidative ability and down-regulating the inflammatory factors expression.

关键词： Cyclocarya paliurus polysaccharide liver injury diabetic rats antioxidants inflammatory factors

Two-year growth of Deep Underground Science and Engineering: A perspective

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DEEP UNDERGROUND SCIENCE AND ENGINEERING 2024年第4期3卷 383-384页

作者： wang, Jianguo Leung, Chunfai Xie, Heping Li, Xiaozhao Yue, Na Hou, Qingping wang, jihong China Univ Min & Technol Sch Mech & Civil Engn Xuzhou 221116 Peoples R China Shaoxing Univ Sch Civil Engn Key Lab Rock Mech & Geohazards Zhejiang Prov Shaoxing Peoples R China Natl Univ Singapore Ctr Offshore Res & Engn Singapore Singapore Shenzhen Univ Inst Deep Earth Sci & Green Energy Shenzhen Peoples R China Sichuan Univ Coll Water Resource & Hydropower Chengdu Peoples R China China Univ Min & Technol State Key Lab Intelligent Construction & Hlth Oper Xuzhou Peoples R China China Univ Min & Technol Editorial Off Deep Underground Sci & Engn Xuzhou Peoples R China

Deep Underground Science and Engineering(DUSE)launched its first issue in September 2022 as a quarterly *** far,it has published 106 articles with nine issues and online early *** volume of received manuscripts increases by 50%each year and over 200 manuscripts were received by 28th of November *** the early period,DUSE authorship came from five countries and now reaches 29 *** articles have been downloaded over 97000 times by readers from 170 countries/*** is indeed encouraging to note that DUSE has been admitted to different indices,including ESCI(August 2024),EI(March 2024),Scopus(July 2023),and DOAJ(May 2023).Its CiteScore in Scopus was 2.2 in 2023 and increased to 5.1 at the mid-November *** first impact factor from the Web of Science will be available in *** is growing to be a rapidly recognized international journal by readers in deep underground research and practice.

关键词： journal admitted underground

Anti-oxidative effect of ribonuclease inhibitor by site-directed mutagenesis and expression in Pichia pastoris

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Frontiers in Biology 2006年第2期1卷 99-103页

作者： Wu Yu Cui Xiuyun wang jihong Zhao Peng Xu Yuefei Zhao Baochang College of Live Sciences Liaoning Normal UniversityDalian 116029China Department of Biochemistry and Molecular Biology Dalian Medical UniversityDalian 116027China

Human placental ribonuclease inhibitor(hRI)is an acidic protein of Mr∼50kDa with unusually high contents of leucine and cysteine *** is a cytosolic protein that protects cells from the adventitious invasion of pancreatic-type *** has 32 cysteine residues,and the oxidative formation of disulfide bonds from those cysteine residues is a rapid cooperative process that inactivates *** most proximal cysteine residues in native hRI are two pairs that are adjacent in *** the present aork,two molecules of alanine substituting for Cys328 and Cys329 were performed by site-directed *** site-mutated RI cDNA was constructed into plasmid pPIC9K and then transformed Pichia pastoris GS115 by *** colony screening,the bacterium was cultured and the product was purified with affinity *** affinity of the recombinant human RI with double site mutation was examined for RNase A and its anti-oxidative *** indicated that there were not many changes in the affinity for RNase A detected when compared with the wild type of *** the capacity of anti-oxidative effect increased by 7~9 *** enhancement in anti-oxidative effect might be attributed to preventing the formation of disulfide bond between Cys328 and Cys329 and the three dimensional structure of RI was thereby maintained.

关键词： ribonuclease inhibitor site-directed mutagenesis cysteine Pichia pastoris reactive oxygen species