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Jet Vectoring Control Using a Novel Synthetic Jet Actuator

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Chinese Journal of Aeronautics 2007年第3期20卷 193-201页

作者： LUO zhen-bing xia Zhi-xun XIE Yong-gao College of Aerospace and Materials Engineering National University of Defense Technology Changsha 410073 China

A primary air jet vectoring control system with a novel synthetic jet actuator （SJA） is presented and simulated numerically. The results show that, in comparison with an existing traditional synthetic jet actuator, which is able to perform the duty of either ＂push＂ or ＂pull＂, one novel synthetic jet actuator can fulfill both ＂push＂ and ＂pull＂ functions to vector the primary jet by shifting a slide block inside it. Therefore, because the new actuator possesses greater efficiency, it has potentiality to replace the existing one in various appli- cations, such as thrust vectoring and the reduction of thermal signature. Moreover, as the novel actuator can fulfill those functions that the existing one can not, it may well be expected to popularize it into more flow control systems.

关键词： jet vectoring control synthetic jet actuator slide block flow control

Dynamics of Coastal Land Use Patterns of Inner Lingdingyang Bay in the Zhujiang River Estuary

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Chinese Geographical Science 2007年第3期17卷 222-228页

作者： xia zhen Jia Peihong Lei Yong Chen Yunzhen The Key Laboratory of Coast&Island Development of Ministry of Education Nanjing UniversityNanjing210093China Guangzhou Marine Geological Survey Guangzhou510760China Jiangsu Provincial Survey Bureau Nanjing210013China

To satisfy the growing of land demand from economic development,a large scale of land reclamation from sea has been carried out in Inner Lingdingyang Bay in the Zhujiang(Pearl)River estuary in recent *** a result,the tidal flat and the water channels became narrow,the frequency of floods increased,and the environment was *** Marine Geological Survey(GMGS)conducted an integrated project for marine geo-environ-ment and geo-hazards survey in *** the integration of multi-temporal remote sensing images of 1977,1978,1988,1996,and 2003,GIS spatial analyzing approach and GPS technique,as well as field data and other background data of the region,this research investigated the comprehensive characteristics and the drivers of coastal land use dy-namics and shoreline changes in Inner Lingdingyang *** results reveal that the reclaimed coastal land was mainly for agriculture and aquaculture in early years,but now they are used for construction sites of harbors and in-dustries,especially high-tech industry.

关键词： Inner Lingdingyang Bay coastal land use pattern land reclamation from sea Zhujiang River estuary

Modeling the circulation and sediment transport in the Beibu Gulf

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Acta Oceanologica Sinica 2017年第4期36卷 21-30页

作者： CHENG Gaolei GONG Wenping WANG Yaping xia zhen School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Collaborative Innovation Center of South China Sea Studies Nanjing University Nanjing 210093 China Center for Coastal Ocean Science & Technology Research School of Marine Sciences Sun Yat-sen University Guangzhou 510275 China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering Guangzhou 510275 China Guangzhou Marine Geological Survey Guangzhou 510075 China

Water circulation and sediment transport in the Beibu Gulf are important for its environmental protection and resource *** employing the Regional Ocean Modeling System（ROMS）,we studied the seasonal variation of circulation,sediment transport and long-term morphological evolution in the Beibu *** simulation results show that the circulation induced by tide and wind is cyclonic both in winter and summer in the gulf and that the wind-driven circulation is stronger in winter than that in *** sediment concentration is higher in the Qiongzhou Strait,west of the Hainan Island and the coast of Vietnam and the Leizhou *** sediment is transported westwards in winter and eastwards in summer in the Qiongzhou *** west entrance of the Qiongzhou Strait is dominated by westward transport all the year *** sediment discharged by rivers is deposited near the river *** simulated result demonstrates that the sediment transport is mainly controlled by tidal induced bottom resuspension in the Beibu *** characteristics are summarized for the distribution patterns of erosion and deposition.（1） The erosion and deposition are insignificant in most area of the gulf.（2） Sediment deposition is more significant in the mouths of Qiongzhou Strait.（3） The erosion is observed in the seabed of Qiongzhou Strait.（4） Erosion and deposition occur alternatively in the west of Hainan Island.

关键词： Beibu Gulf circulation sediment transport Regional Ocean Modeling System(ROMS)

Electro-generation of TGA by Ni-mSA-mCS bipolar membrane

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Chinese Chemical Letters 2007年第11期18卷 1411-1415页

作者： zhen xia Huang Xi zheng Ri Yao Chen xiao Chen zhen Chen Experiment Center College of Chemistry and Materials Science Fujian Normal University Fuzhou 350007 China

Ni-mSA-mCS bipolar membrane （BM） was prepared by sodium alginate （SA） and chitosan （CS）, which were modified by Ca^2＋ and glutaraldehyde as linking reagents, respectively, mSA-mCS membrane was characterized by FTIR, SEM, TG and used as a separator in the electrolysis cell to produce thioglycolic acid （TGA）. The experiment results show that TGAwas prepared effectively by electro-reduction of dithiodiglycolic acid （DTDGA） with the mixture of TGA and DTDGA in the cathodic chamber. The current efficiency was up to 66.7% at the room temperature （25 ℃） during the current density of 10 mA/cm^2. Compared with the traditional metal reduction method, the electro-reduction technology saves the zinc powder and eliminates the pollution to environment.

关键词： Bipolar membrane Modified sodium alginate Modified chitosan Thioglycolic acid Dithiodiglycolic acid

Preparation of Ti–Nb–Ta–Zr alloys for load-bearing biomedical applications

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Rare Metals 2019年第6期38卷 571-576页

作者： Bo-Qiong Li Chun-Lin Li zhen-xia Wang Xing Lu Department of Mechanical Engineering Jinzhong UniversityJinzhong 030619China College of Material Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Liaoning Key Materials Laboratory for Railway School of Materials Science and EngineeringDalian Jiaotong UniversityDalian 116028China

Ti–Nb–Ta–Zr alloys for biomedical applications were successfully fabricated by arc melting(AM) and diffusion *** microstructure, mechanical properties and electrochemistry behavior in a simulated body fluid(SBF) were *** shows that melted Ti–Nb–Ta–Zr alloy mainly contains β phase although there are a few Ti-rich phases and micropores, the number of which is lower than that in sintered sample with a few Ti-rich and Ta-rich *** melted alloys present higher strength(1224 MPa), Young’s modulus(15.3 GPa) and corrosion potential(-0.34 V) in SBF, while total recovery strain ratio(67.5%) and pseudoelastic strain ratio(8.4%) of sintered Ti–Nb–Ta–Zr alloy keep higher value than 35.7%and 5.0% for melted Ti–Nb–Ta–*** reasons were discussed based on the microstructure of the Ti–Nb–Ta–Zr alloys.

关键词： Titanium alloys Microstructure Compressive behavior SBF

G-quadruplexes in genomes of viruses infecting eukaryotes or prokaryotes are under different selection pressures from hosts

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Journal of Genetics and Genomics 2022年第1期49卷 20-29页

作者： zhen Li Sheng Hu Qian Fan Wang Hany IMohamed Guangfu Yang zhen-xia Chen Dengguo Wei State Key Laboratory of Agricultural Microbiology College of Veterinary MedicineHuazhong Agricultural UniversityWuhanHubei 430070China Hubei Hongshan Laboratory Huazhong Agricultural UniversityWuhan 430070China Interdisciplinary Sciences Institute Huazhong Agricultural UniversityWuhan 430070China College of Science Huazhong Agricultural UniversityWuhan 430070China College of Biomedicine and Health Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China International Joint Research Center for Intelligent Biosensor Technology and Health Central China Normal UniversityWuhan 430079China Chemistry Department Faculty of ScienceBenha UniversityBenha 13518Egypt Hubei Key Laboratory of Agricultural Bioinformatics College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityShenzhen 518124China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518124China National Reference Laboratory of Veterinary Drug Residues(HZAU)and MAO Key Laboratory for Detection of Veterinary Drug Residues Huazhong Agricultural UniversityWuhanHubei 430070China

G-quadruplexes in viral genomes can be applied as the targets of antiviral therapies, which has attracted wide interest. However, it is still not clear whether the pervasive number of such elements in the viral world is the result of natural selection for functionality. In this study, we identified putative quadruplex-forming sequences(PQSs) across the known viral genomes and analyzed the abundance, structural stability, and conservation of viral PQSs. A Viral Putative G-quadruplex Database(http://***/MBPC/Vi PGD/***/home/index) was constructed to collect the details of each viral PQS, which provides guidance for selecting the desirable PQS. The PQS with two putative G-tetrads(G2-PQS) was significantly enriched in both eukaryotic viruses and prokaryotic viruses, whereas the PQSs with three putative G-tetrads(G3-PQS) were only enriched in eukaryotic viruses and depleted in prokaryotic viruses. The structural stability of PQSs in prokaryotic viruses was significantly lower than that in eukaryotic viruses. Conservation analysis showed that the G2-PQS, instead of G3-PQS, was highly conserved within the genus. This suggested that the G2-quadruplex might play an important role in viral biology, and the difference in the occurrence of G-quadruplex between eukaryotic viruses and prokaryotic viruses may result from the different selection pressures from hosts.

关键词： G-quadruplex Selection pressure Database Evolution

Synthesis of Obyanamide, a Marine Cytotoxic Cyclic Depsipeptide

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Chinese Chemical Letters 2006年第3期17卷 285-288页

作者： Wei ZHANG Ni SONG Zhong zhen LI Ying xia LI Key Laboratory of Marine Drugs the Ministry of Education of China Marine Drug and Food Institute Ocean University of China Qingdao 266003

The synthesis of a marine cytotoxic cyclic depsipeptide obyanamide has been accomplished. The key steps include assembling liner pentapeptide via Yamaguchi esterification and HATU-promoted ring closing. The structure of the synthetic sample was identified by ^1H and ^13C NMR, H-H COSY, HMQC, HMBC, and HRESIMS, but appears to be different from that of the marine natural product.

关键词： Obyanamide synthesis cyclic depsipeptide natural product.

Van der Waals heterostructure tunnel FET with potential modulation beyond junction region

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Science China(Information Sciences) 2022年第10期65卷 311-313页

作者： Wenjing QIN Yawei LV zhen xia Lei LIAO Changzhong JIANG Key Laboratory for Micro-/Nano-Optoelectronic Devices of the Ministry of Education School of Physics and Electronics Hunan University School of Physics and Electronics Hunan Normal University School of Physics and Technology Wuhan University

Dear editor,State-of-the-art semiconductor technology is approaching the atomic scale, greatly boosting the switching behavior of transistors towards the physical limit of the thermionic emission mechanism [1, 2]. A fundamental revolution is needed to break this limit and reduce power *** to the band-to-band tunneling mechanism,

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Molecularly Imprinted Polymers on Chloromethyl Polystyrene Resin Prepared via RAFT Polymerization

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Chinese Chemical Letters 2006年第4期17卷 549-552页

作者： zhen xia DU Hong LIU Zhi Feng FU Wan Tai YANG Key Laboratory for Controlled Chemical Reactions of Education Ministry Beijing University of Chemical Technology Beijing 100029

Surface molecularly imprinted polymers （SMIP） was prepared via the reversible addition-fragmentation chain transfer （RAFT） polymerization on the chloromethyl polystyrene resin （CPR） in the presence of the template D-phenylalanine. The structure of SMIP was characterized by FTIR and SEM. The adsorption behavior of D-phenylalanine of SMIP was preliminarily investigated.

关键词： Surface molecularly imprinted polymers reversible addition-fragmentation chain transfer.