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Review of fluid and control technology of hydraulic wind turbines

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Frontiers of Mechanical Engineering 2017年第3期12卷 312-320页

作者： Maolin CAI Yixuan WANG Zongxia jiao yan SHI School of Automation Science and Electrical Engineering BeihangUniversity Beijing 100191 China

This study examines the development of the fluid and control technology of hydraulic wind turbines. The current state of hydraulic wind turbines as a new technology is described, and its basic fluid model and typical control method are expounded by comparing various study results. Finally, the advantages of hydraulic wind turbines are enumerated. Hydraulic wind turbines are expected to become the main development direction of wind turbines.

关键词： wind turbine hydraulic system fluid model,control technology

Biogenic C-doped titania templated by cyanobacteria for visible-light photocatalytic degradation of Rhodamine B

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Journal of Environmental Sciences 2014年第5期26卷 1195-1202页

作者： jiao He Guoli Zi Zhiying yan Yongli Li jiao Xie Deliang Duan Yongjuan Chen Jiaqiang Wang The Universities' Center for Photocatalytic Treatment of Pollutants in Yunnan Province Key Laboratory of Medicinal Chemistry for Natural Resources Ministry of Education School of Chemical Sciences & Technology Yunnan University

Cyanobacteria, which occurred in eutrophic water harvest solar light to carry out photosynthesis with high efficiency. In this work, cyanobacteria （Microcystis sp.） were used as biotemplate to synthesize titania structure. The synthesized titania sample had similar morphology to that of the original template in spite of the fragile unicellular structures and extremely high water content of cyanobacterial cells. Incorporation of biogenic C, as well as the morphology inherited from biotemplate improved visible- light absorbance of the titania structure. The sample exhibited higher visible-light photocatalytic activity than commercial titania photocatalyst Degussa P25 for Rhodamine B （RhB） degradation. Compared with those C-doped titania photocatalysts prepared by other methods, cyanobacteria templated titania photocatalyst offer some potential for competitive advantages. The reported strategy opened up a new use for the cyanobacteria. It could also be used for titania in applications such as treatment of polluted water, dye-sensitized solar cells, or other regions.

关键词： cyanobacteria titania C-doped visible-light photocatalysis

Chromatic framework for quantum movies and applications in creating montages

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Frontiers of Computer Science 2018年第4期12卷 736-748页

作者： Fei yan Sihao jiao Abdullah M. ILIYASU Zhengang JIANG School of Computer Science and Technology Changchun University of Science and Technology Changchun 130022 China Electrical Engineering Department College of Engineering Prince Sattam Bin Abdulaziz University Al-Kharj 11942 Saudi Arabia

A framework that introduces chromatic considerations to earlier descriptions of movies on quantum computers is proposed. This chromatic framework for quantum movies （CFQM） integrates chromatic components of individual frames （each a multi-channel quantum image - MCQI state） that make up the movie, while each frame is tagged to a time component of a quantum register （i.e., a movie strip）. The formulation of the CFQM framework and properties inherent to the MCQI images facilitate the execution of a cortege of carefully formulated transformations including the frame-to-frame （FTF）, color of interest （COI）, and subblock swapping （SBS） operations that are not realizable on other quantum movie formats. These innovative transformations are deployed in the creation of digital movie-like montages on the CFQM framework. Future studies could explore additional MCQI-related operations and their use to execute more advanced montage applications.

关键词： quantum information quantum computation quantum image processing quantum movie montage

Direct numerical simulation of low Reynolds number turbulent air-water transport in fuel cell flow channel

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Science Bulletin 2017年第1期62卷 31-39页

作者： Zhiqiang Niu Renfang Wang Kui jiao Qing Du yan Yin State Key Laboratory of Engines Tianjin UniversityTianjin 300072China Sunrise Power Co. Ltd.Dalian 116085China

With performance improvement of low-temperature fuel cell(FC), high reactant supply and water generation rates may induce air-water turbulence in the FC flow channel. In this research, an air-water turbulent direct numerical simulation(DNS) model is developed to simulate different droplet sizes,locations and interactions in the air-water transport processes comprehensively. It is found that a larger droplet breaks up more easily in turbulence, and a smaller droplet tends to keep lumped. The droplet at corner does not break up because it is away from channel center. The droplet interaction simulations show that the small droplets merge to form slugs, but still keep lumped in turbulence. It is suggested that two conditions need to be satisfied for droplet break up in FC flow channel, one is turbulent flow, and another is that the droplet needs to be large enough and occupy the center region of flow channel to suffer sufficient turbulence fluctuations. The DNS results illustrate some unique phenomena in turbulent flow, and show that the turbulence has significant effect on the air-water flow behavior in FC flow channel.

关键词： DNSFuel cell Turbulence Air-water flow

Resolving the influence of nitrogen abundances on sediment organic matter in macrophyte-dominated lakes, using fluorescence spectroscopy

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Journal of Environmental Sciences 2015年第1期27卷 197-206页

作者： Xin Yao Shengrui Wang Lixin jiao Caihong yan Xiangcan Jin State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory for Lake Pollution Control Research Center of Lake Eco-environment Chinese Research Academy of Environmental Sciences School of Environment and Planning Liaocheng University

A controlled experiment was designed to resolve the influence of nitrogen abundance on sediment organic matters in macrophyte-dominated lakes using fluorescence *** biomass showed coincident growth trends with time, but different variation rates with nitrogen treatment. All plant growth indexes with nitrogen addition（N, NH4Cl100, 200, 400 mg/kg, respectively） were lower than those of the control group. Four humiclike components, two autochthonous tryptophan-like components, and one autochthonous tyrosine-like component were identified using the parallel factor analysis model. The results suggested that the relative component changes of fluorescence in the colonized sediments were in direct relation to the change of root biomass with time. In the experiment, the root formation parameters of the plants studied were significantly affected by adding N in sediments, which may be related to the reason that the root growth was affected by N *** a low concentration of N to sediments can play a part in supplying nutrients to the plants. However, the intensive uptake of NH4^＋may result in an increase in the intracellular concentration of ammonia, which is highly toxic to the plant cells. Hence, our experiment results manifested that organic matter cycling in the macrophyte-dominated sediment was influenced by nitrogen enrichment through influencing vegetation and relevant microbial activity.

关键词： Colonized sediment Non-colonized sediment Nitrogen enrichment Submersed macrophyte Sediment organic matter Fluorescence feature

SICA for Cox's Proportional Hazards Model with a Diverging Number of Parameters

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 887-902页

作者： Yue-Yong SHI Yong-Xiu CAO Yu-Ling jiao yan-yan LIU School of Mathematics and Statistics Wuhan University

The smooth integration of counting and absolute deviation （SICA） penalized variable selection procedure for high-dimensional linear regression models is proposed by Lv and Fan （2009）. In this article, we extend their idea to Cox＇s proportional hazards （PH） model by using a penalized log partial likelihood with the SICA penalty. The number of the regression coefficients is allowed to grow with the sample size. Based on an approximation to the inverse of the Hessian matrix, the proposed method can be easily carried out with the smoothing quasi-Newton （SQN） algorithm. Under appropriate sparsity conditions, we show that the resulting estimator of the regression coefficients possesses the oracle property. We perform an extensive simulation study to compare our approach with other methods and illustrate it on a well known PBC data for predicting survival from risk factors.

关键词： Cox proportional hazards models penalized partial likelihood diverging parameters oracle prop-erty smoothing quasi-Newton

Microstructure and mechanical properties of cryorolled AZ31 magnesium alloy sheets with different initial textures

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 827-834页

作者： Jin-ru Luo Ya-qiong yan Ji-shan Zhang Lin-zhong Zhuang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

AZ31 magnesium alloy sheets with different strong textures were cryorolled at the liquid-nitrogen temperature to the strain of 4% and 8%. The microstructure and texture of the rolled sheets were investigated via scanning electron microscopy（SEM）, electron backscatter diffraction（EBSD）, and X-ray diffraction（XRD）. The mechanical properties of the sheets were tested through in-plane uniaxial tensile tests at ambient temperature. The tensile stress was exerted in the rolling direction（RD） and transverse directions（TD）. The microstructural and textural evolutions of the alloy during cryorolling were investigated. Due to active twining during rolling, the initial texture significantly influenced the microstructural and textural evolutions of the rolled sheets. A {10 12} extension twin was found as the dominated twin-type in the cryorolled samples. After cryogenic rolling, the ductility of the samples decreased while the strength increased. Twinning also played an important role in explaining the mechanical differences between the rolled samples with different initial textures. The samples were significantly strengthened by the high stored energy accumulated from cryorolling.

关键词： magnesium alloy cryorolling microstructure mechanical properties twinning

Analysis of Organic Acids Accumulated in Kochia Scoparia Shoots and Roots by Reverse-phase High Performance Liquid Chromatography Under Salt and Alkali Stress

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Chemical Research in Chinese Universities 2006年第3期22卷 315-318页

作者： yan Hong ZHAO Wei jiao Xin-qian yan Bing-jun ZHOU Dao-wei School of Life Sciences Northeast Normal University Changchun 130024 P.R. China Department of Avigation Lifesaving Avigation University of Air Force Changchun 130022 P. R. China College of Environment and Resources Jilin University Changchun 130012 P. R. China

Several organic acids accumulated in Kochia Scoparia shoots and roots were studied by means of reverse-phase high performance liquid chromatography with a C18 column. Five types of binary organic acids were separated. The organic acid concentrations were determined in K. Scoparia seedlings stressed by saline （NaCI） and alkaline （NaHCO3） at the same Na^＋ concentration. Concentrations of organic acids are stimulated by alkaline because the cells will adjust their pH values through the accumulation of organic acids, when the environment is basic. The concentrations of oxalic acid and succinic acid are higher than those of other organic acids, including tartaric acid and malic acid, and the concentration of citric acid is the lowest. The concentrations of the organic acids in the roots are higher than those in the shoots under salt（NaCI） stress, but the results are opposite while the roots are under alkali （ NaHCO3 ） stress. This indicates that there are different adaptive strategies for K. Scopar/a seedlings in organic acid metabolism under salt and alkali stress.

关键词： Kochia Scoparia(L. ) Sehrad Salt stress Alkaline stress Organic acid HPLC

Synthetic control of chiral pore surfaces in covalent organic frameworks for enantioselective separation of chiral drugs

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Science China Chemistry 2025年

作者： Shiguo Fu Xiaofeng Zhang Kaixuan Wang Linfeng Chen Fan Xia Yong Cui yan Liu School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Faculty of Materials Science and Chemistry China University of Geosciences

Enantioselective separations of racemates using porous materials are highly attractive and significant in both fundamental research and technological applications. However, achieving controlled chiral pore surfaces to create the necessary driving force for enantiomer discrimination poses a fundamental challenge. Herein, we demonstrate that chiral covalent organic frameworks(COFs) possess the essential characteristics for effective enantioseparations through synthetic control over pore surfaces. We synthesized three 3D chiral COFs (CCOFs) featuring abundant chiral recognition sites on the pore walls via the condensation of enantiopure dialdehyde of 2,2′-dihydroxy-1,1′-binaphthyl and tetraamine. All CCOFs with high stability exhibit an 11-fold interpenetrated framework with tubular open channels, decorated with dihydroxyl or diethoxyl groups. The CCOFs with dihydroxyl groups serve as solid adsorbents for the adsorptive separation and solid-phase extraction of various chiral 1-phenylethanol-derived enantiomers, particularly racemic drugs, achieving up to 98%enantiomeric excess. In contrast, the CCOF with diethoxy groups is unable to resolve the racemates. These CCOF materials can be recycled and reused without any apparent loss of performance. Density functional theory (DFT) calculations reveal that the enantiospecific recognition arises from the well-organized chiral inner sphere and multiple chiral host-guest interactions.

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