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Characteristics of viscous debris flow in a drainage channel with an energy dissipation structure

Journal of Mountain Science 2016年第2期13卷 223-233页

作者： CHEN jian-gang CHEN xiao-qing CHEN Hua-yong ZHAO Wan-yu CAS Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China CAS Center for Excellence in Tibetan Plateau Earth Sciences

A new type of drainage channel with an energy dissipation structure has been proposed based on previous engineering experiences and practical requirements for hazard mitigation in earthquakeaffected *** studies were performed to determine the characteristics of viscous debris flow in a drainage channel of this type with a slope of 15%.The velocity and depth of the viscous debris flow were measured,processed,and subsequently used to characterize the viscous debris flow in the drainage *** of this experiment showed that the surface of the viscous debris flow in a smooth drainage channel was smoother than that of a similar debris flow passing through the energy dissipation section in a channel of the new type studied ***,the flow patterns in the two types of channels were similar at other *** experimental results show that the depth of the viscous debris flow downstream of the energy dissipation structure increased gradually with the length of the energy dissipation *** addition,in the smooth channel,the viscous debris-flow velocity downstream of the energy dissipation structure decreased gradually with the length of the energy dissipation ***,theviscous debris-flow depth and velocity were slightly affected by variations in the width of the energy dissipation structure when the channel slope was 15%.Finally,the energy dissipation ratio increased gradually as the length and width of the energy dissipation structure increased;the maximum energy dissipation ratio observed was 62.9%(where B = 0.6m and L/w = 6.0).

关键词： Debris flow Drainage channel Energy dissipation structure Geological disaster

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Dynamic channel reservation scheme based on priorities in LEO satellite systems

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Journal of Systems Engineering and Electronics 2015年第1期26卷 1-9页

作者： jian Zhou xiaoguo Ye yong Pan Fu xiao Lijuan Sun College of Computer Nanjing University of Posts and Telecommunications

According to low earth orbit（LEO） satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satellites firstly. Then, a channel allocation model based on Markov is established. Finally, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effectively reduces handover failures and improves channel utilization by adjusting dynamically the thresholds according to traffic conditions. The simulation results show that the system＇s overall quality of service can be improved by this strategy.

关键词： dynamic channel reservation priority handover different level user low earth orbit(LEO)

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NUMERICAL SOLUTION OF 2-D INCOMPRESSIBLE VISCOUS FLOW WITH HIGH ORDER COMPACT SCHEME USING DOMAIN DECOMPOSITION AND MATCHED METHOD

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Journal of Hydrodynamics 2001年第4期13卷 79-82页

作者： Ren, An-Lu Lu, xiao-Dong Zou, jian-Feng Zhou, yong-Xia Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

This paper presents a high-accuracy method for solving 2-D incompressible viscous N-S equations in tensor forms. A domain decomposition method was used to divide the computational domain into several regular blocks with the overlapping grid in order to transfer data between sub-domains and to remove numerical singularity caused by domain decomposition. Using the method and algorithm presented above, the flow passing an ellipse was computed and the formation and evolution of the vortex shedding was successfully simulated.

关键词： Computational fluid dynamics Computational methods Incompressible flow Navier Stokes equations

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Synthesis of novel benzo[b]pyrimido[4',5':5,4]thieno[2,3-e][1,6]naphthyridine-8-ones via Pictet–Spengler cyclization

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Chinese Chemical Letters 2016年第2期27卷 261-264页

作者： Dao-Lin Wang xiao-Ce Shi yong-Yang Wang jian Ma College of Chemistry and Chemical Engineering Liaoning Key Laboratory of Synthesis and Application of Functional Compound Bohai University

An efficient method for the synthesis of novel benzo[b]pyrimido[4′,5′：5,4]thieno[2,3e]-[1,6]naphthyridine-8-one derivatives via Pictet-Spengler cyclization is reported. The reaction of 4-（3-aminopyrimido[4,5-d]thieno-2-yl）quinoline-2-ones, which could be obtained from Thorpe-Ziegler isomerization of 4-bromomethylquinoline-2-ones and 5-cyano-1,6-dihydro-4-methyl-2-phenyl-6-thioxopyrimidine,with aromatic aldehydes in the presence of BF3·OEt2 gives pyrimidothieno[1,6]naphthyridines in good yields.

关键词： 4-Bromomethylquinoline-2-one 5-Cyano-6-thioxopyrimidine Pyrimido[4′,5′:5,4]thieno[2-3e]naphthyridine Thorpe-Ziegler reaction Pictet-Spengler reaction

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Parameter estimation for rigid body after micro-Doppler removal based on L-statistics in the radar analysis

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Journal of Systems Engineering and Electronics 2015年第3期26卷 457-467页

作者： yong Wang jian Kang School of Electronics and Information Engineering Harbin Institute of Technology

In traditional inverse synthetic aperture radar （ISAR） imaging of moving targets with rotational parts, the micro-Doppler （m-D） effects caused by the rotational parts influence the quality of the radar images. Recently, L. Stankovic proposed an m-D removal method based on L-statistics, which has been proved effective and simple. The algorithm can extract the m-D effects according to different behaviors of signals induced by rotational parts and rigid bodies in time-frequency （T-F） domain. However, by removing m-D effects, some useful short time Fourier transform （STFT） samples of rigid bodies are also extracted, which induces the side lobe problem of rigid bodies. A parameter estimation method for rigid bodies after m-D removal is proposed, which can accurately re- cover rigid bodies and avoid the side lobe problem by only using m-D removal. Simulations are given to validate the effectiveness of the proposed method.

关键词： parameter estimation L-statistics micro-Doppler (m-D) radar imaging.

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An efficient synthesis of novel benzo[b]pyrido[3',2':4,5]thieno[2,3-e][1,6]naphthy-ridine-8-ones

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Chinese Chemical Letters 2015年第9期26卷 1109-1112页

作者： Dao-Lin Wang yong-Yang Wang xiao-Ce Shi jian Ma College of Chemistry and Chemical Engineering Liaoning Key Laboratory of Synthesis and Application of Functional Compound Bohai University

An efficient method for the synthesis of novel benzo[b]pyrido[3＇,2＇：4,5]thieno[2,3-e][l,6]naphthyridine-8-one derivatives has been developed using a Pictet-Spengler reaction between 4-（3-aminothieno[2,3-b]pyridin-2-yl）quinoline-2-ones,which could be obtained from the alkylation of4-bromomethylquinoline-2-ones with 3-cyanopyridine-2-thione followed by a Thorpe-Ziegler isomerization,and aromatic aldehydes under p-TsOH as catalysis in good yields.

关键词： 4-Bromomethylquinoline-2-one 3-Cyanopyridine-2-thione Benzo[b]pyrido[3' 2':4 5 ]thieno[23-e][1 6] naphthyridine-8-one Thorpe-Ziegler reaction Pictet-Spengler reaction

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A review of the Cypriniform tribe Yunnanilini Prokofiev,2010 from China,with an emphasis on five genera based on morphologies and complete mitochondrial genomes of some species

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Zoological Research 2021年第3期42卷 310-334页

作者： Li-Na Du jian Yang Rui Min xiao-yong Chen Jun-Xing Yang Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilinGuangxi 541004China Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life ScienceGuangxi Normal UniversityGuilinGuangxi 541004China Key Laboratory of Environment Change and Resources Use in Beibu Gulf Nanning Normal UniversityNanningGuangxi 530001China Kunming Institute of Zoology Chinese Academy of SciencesKunmingYunnan 650223China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyThe Innovative Academy of Seed DesignChinese Academy of SciencesKunmingYunnan 650223China Yunnan Key Laboratory of Plateau Fish Breeding Yunnan Engineering Research Center for Plateau-Lake Health and RestorationKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China

The loach tribe Yunnanilini from China is reviewed here using morphological characters and complete mitochondrial genomes of select *** data suggest that the tribe Yunnanilini is not monophyletic and can be divided into three *** of the Yunnanilus nigromaculatus group form an independent genus and are placed in *** the phylogenetic tree,*** clusters with Paranemachilus genilepis,and *** clusters with Micronemacheilus cruciatus,indicating that *** and *** belong to Paranemachilus and Micronemacheilus,*** on while *** and ***,are placed in Paranemachilus and Micronemacheilus,*** niulanensis and *** are treated as junior synonyms of Eonemachilus ***,Micronemacheilus,and Yunnanilus are show short separation between anterior and posterior *** genera can be distinguished from each other by mouth structure,lateral line and cephalic lateral-line canals,and papillae on median part of both *** anterior and posterior nostrils of Heminoemacheilus and Paranemachilus are closely *** and Micronemacheilus are distinguished by cheeks covered with scales and lips with papillae,*** phylogenetic tree and morphological characters support Traccatichthys as a valid genus,which can be distinguished from Micronemacheilus by anterior and posterior nostrils closely set(*** separated).Four species are placed in Traccatichthys.

关键词： Eonemachilus Heminoemacheilus Micronemacheilus,Paranemachilus,Yunnanilus Taxonomy

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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

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Shaking table test of seismic responses of anchor cable and lattice beam reinforced slope

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Journal of Mountain Science 2020年第5期17卷 1251-1268页

作者： ZHANG jian-jing NIU Jia-yong FU xiao CAO Li-cong XIE Qiang School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Chengdu City Construction Investment&Management Group Co.Ltd. Chengdu 610036China

As a combined supporting structure,the anchor cable and lattice beam have a complex interaction with the slope *** order to investigate the seismic behaviors of the slope reinforced by anchor cable and lattice beam,a largescale shaking table test was carried out on a slope model(geometric scale of 1:20)by applying recorded and artificial seismic waves with different *** acceleration and displacement of the slope,the displacement of lattice beam and the axial force of anchor cable were obtained to study the interaction between the slope and the supporting *** test results show that:(1)the acceleration responses of the slope at different relative elevations display obvious nonlinear characteristics with increasing of the peak ground acceleration(PGA)of the inputted seismic waves,and the weak intercalated layer has a stronger effect on acceleration amplification at the upper part of the slope than that at the lower part of the slope;(2)the frequency component near the second dominant frequency is significantly magnified by the interaction between the slope and the supporting structure;(3)the anchor cables at the upper part of the slope have larger peak and residual axial forces than that at the lower part of the slope,and the prestress loss of the anchor cable first occurs at the top of the slope and then passes down;(4)the peak and residual displacements inside the slope and on the lattice beam increase with the increase of relative *** the inputted PGA is not greater than 0.5 g,the combined effect of anchor cable and lattice beam is remarkable for stabilizing the middle and lower parts of the potential sliding *** research results can provide a reference for the seismic design of such slope and the optimization of supporting structure.

关键词： Earthquake engineering Shaking table test Anchor cable Lattice beam Dynamic response

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Impact of oxygen supply on production of terpenoids by microorganisms: State of the art

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Chinese Journal of Chemical Engineering 2021年第2期34卷 46-53页

作者： Ting-Ting Liu Han xiao jian-Hui xiao jian-jiang Zhong State Key Laboratory of Microbial Metabolism Joint International Research Laboratory of Metabolic and Developmental SciencesLaboratory of Molecular Biochemical Engineering and Advanced Fermentation TechnologyDepartment of BioengineeringSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Zunyi Municipal Key Laboratory of Medicinal Biotechnology Center for Translational MedicineAffiliated Hospital of Zunyi Medical UniversityZunyi 563003China

Terpenoids are a class of high value-added natural products with a variety of biological *** engineered microorganisms,such as those of Escherichia coli and Saccharomyces cerevisiae,have merits in producing plant or fungus-derived terpenoids,due to their mature genetic manipulation,simple nutrient demand and fast ***,as a key environmental factor,is particularly important to microbial metabolism and growth,and suitable oxygen supply is viewed as a prerequisite for realizing highly efficient production of terpenoids by engineered *** this article,the role of oxygen in regulating terpenoid bioproduction is overviewed from the viewpoints of cellular carbon metabolism,energy metabolism and terpenoid *** on adjusting oxygen availability to microorganisms,including genetic modification of cellular metabolism related with oxygen utilization,are summarized and discussed,to provide helpful information for further improvement of terpenoid biosynthesis by microbes.

关键词： Terpenoid Microorganisms Oxygen supply Chassis modification

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