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A general alternate loading technique and its applications in the inverse designs of centrifugal and mixed-flow pump impellers

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Science China(Technological sciences) 2021年第4期64卷 898-918页

作者： WANG ChaoYue WANG FuJun AN DongSen YAO ZhiFeng XIAO RuoFu LU Li HE ChengLian ZOU ZhiChao College of Water resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China China Institute of Water resources and Hydropower Research Beijing 100038China China Water resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

For the inverse designs of centrifugal and mixed-flow pump impellers,clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller *** this paper,to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller,a simple kinematic equation is derived based on the ideal assumptions,which indicates that the potential rothalpy gradient(PRG)is the most important dynamic source that actively induces secondary vortical *** by the natural adverse PRG on the S1 and S2 stream surfaces,two typical secondary flows,H-S and P-S secondary flows,are clearly *** specially suppress these typical secondary flows,a general alternate loading technique(GALT)is proposed,aiming to adjust the real blade loadingδp to control the PRG *** the blade fore part,theδp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 *** the blade middle part,theδp should be moderately decreased to reduce adverse streamwise PRG on the S1 *** the blade aft part,the difference in theδp between the shroud and hub streamlines should be decreased faster to control the exit *** applying the GALT to the impeller designs of three typical pump types in hydraulic engineering,the organizational effect of the PRG on fundamental flow structures is *** GALT can effectively control the PRG distributions and suppress the secondary flows,thereby widening the pump’s high-efficiency zone,improving flow uniformity and suppressing pressure *** with the current Z-G method and the ALT,the GALT can meet the requirements of"de-experience"better,thereby enabling the designers to obtain good products explicitly and quickly.

关键词： alternate loading technique inverse design centrifugal pump mixed-flow pump impeller potential rothalpy gradient

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Competitiveness of alga Microcystis aeruginosa co-cultivated with cyanobacterium Raphidiopsis raciborskii confirms its dominating position

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Journal of Oceanology and Limnology 2022年第5期40卷 1804-1818页

作者： Zengling MA Xiaoqiao ZHANG Renhui LI Min WANG Wenli QIN He ZHANG Gang LI Henguo YU Chuanjun DAI Min ZHAO Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological resources Protection Wenzhou UniversityWenzhou 325035China National and Local Joint Engineering Research center of Ecological Treatment Technology for Urban Water Pollution Wenzhou UniversityWenzhou 325035China Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Microcystis aeruginosa has always been regarded as the main culprit of cyanobacterial blooms in ***,in recent years,Raphidiopsis raciborskii has gradually replaced *** as the culprit of cyanobacterial blooms in some tropical and subtropical shallow *** reveal which one plays a more dominant role,interactions between cylindrospermospin(CYN)-producing *** and microcystins(MCs)-producing or non-MCs-producing *** strains were studied using bialgal cultures at different initial ratios of biomasses of the two species at 25℃.During the co-cultivation,the *** strains inhibited the growth and heterocyst formation of *** filaments,and thus occupied a dominant position during the co-cultivation regardless of the initial biomass ratios in the *** addition,the MCs-producing M aeruginosa strain contributed to a higher portion of the total biomass and exerted a stronger inhibitory effect on *** compared with the non-MCs-producing ***,the growth of both MCs-producing and non-MCs-producing *** strains was stimulated by *** in the co-cultures compared with *** monoculture,indicating that *** could outcompete *** if given enough time,enabling it to develop into the dominant species even in very low initial *** our best knowledge,this is the first report on the loss of heterocyst formation by a species of cyanobacteria that resulted from interactions between two different species of *** findings indicate that it is difficult for *** to replace the dominant position of *** under the experimental environmental condition,and the allelopathic effects of *** on *** could significantly contribute to the success of ***.

关键词： competition growth heterocyst Microcystis aeruginosa morphology Raphidiopsis raciborskii

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Designing of highly selective and high-temperature endurable RWGS heterogeneous catalysts: recent advances and the future directions

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Journal of Energy Chemistry 2017年第5期26卷 854-867页

作者： Xiong Su Xiaoli Yang Bo Zhao Yanqiang Huang iChEM (Collaborative Innovation center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of sciences renewable Energy Storage Division Global Energy Interconnection Research Institute (GEIRI)Future Science and Technology City

Reverse water gas shift（RWGS） reaction can be served as a pivotal stage of transitioning the abundant CO;resource into chemicals or hydrocarbon fuels, which is attractive for the CO;utilization and of eventually significance in enabling a rebuilt ecological system for unconventional fuels. This concept is appealing when the process is considered as a solution for the storage of renewable energy, which may also find a variety of potential end uses for the outer space exploration. However, a big challenge to this issue is the rational design of high temperature endurable RWGS catalysts with desirable CO product selectivity. In this work, we present a comprehensive overview of recent publications on this research topic,mainly focusing on the catalytic performance of RWGS reaction over three major kinds of heterogeneous catalysts, including supported metal catalysts, mixed oxide catalysts and transition metal carbides. The reaction thermodynamic analysis, kinetics and mechanisms are also described in detail. The present review attempts to provide a general guideline about the construction of well-performed heterogeneous catalysts for the RWGS reaction, as well as discussing the challenges and further prospects of this process.

关键词： RWGS reaction Carbon dioxide hydrogenation Supported metal catalyst Metal oxide Transition metal carbide

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Ecological impacts of the expansion of offshore wind farms on trophic level species of marine food chain

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Journal of Environmental sciences 2024年第5期139卷 226-244页

作者： Lijing Wang Bangguo Wang Wenxi Cen Rui Xu Yuwei Huang Xin Zhang Yinghui Han Yuanxun Zhang College of resources and Environment University of Chinese Academy of SciencesBeijing 101408China Yanshan Earth Critical Zone and Surface Fluxes Research Station University of Chinese Academy of SciencesBeijing 101408China Chinese Research Academy of Environmental sciences Beijing 100012China National Joint Research center for Yangtze River Conservation Beijing 100012China College of Environmental Engineering Beijing University of TechnologyBeijing 100124China Institute of Eco-Environmental Forensics Shandong UniversityQingdao 266237China

The global demand for renewable energy has resulted in a rapid expansion of offshore wind farms(OWFs)and increased attention to the ecological impacts of OWFs on the marine *** reviews mainly focused on the OWFs’impacts on individual species like birds,bats,or *** review collected numerous field-measured data and simulated results to summarize the ecological impacts on phytoplankton,zooplankton,zoobenthos,fishes,and mammals from each trophic level and also analyze their interactions in the marine food *** and zooplankton are positively or adversely affected by the‘wave effect’,‘shading effect’,oxygen depletion and predation pressure,leading to a ±10% fluctuation of primary *** zoobenthos are threatened transiently by habitat destruction with a reduction of around 60% in biomass in the construction stage,their abundance exhibited an over 90% increase,dominated by sessile species,due to the‘reef effect’in the operation *** fishes and mammals are to endure the interferences of noise and electromagnetic,but they are also aggregated around OWFs by the‘reef effect’and‘reserve effect’.Furthermore,the complexity of marine ecosystem would increase with a promotion of the total system biomass by 40% through trophic cascade effects strengthen and resource partitioning alternation triggered by the proliferation of *** suitable site selection,long-term monitoring,and life-cycle-assessment of ecological impacts of OWFs that are lacking in current literature have been described in this review,as well as the carbon emission and deposition.

关键词： Offshore wind farms(OWFs) Ecological impacts Plankton Benthos Fish Mammal

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Phosphine ligands featuring C-N chiral axis applicable to tetra-ortho-substituted biaryl synthesis

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Chinese Chemical Letters 2023年第7期34卷 3-5页

作者： Weiwei Fang Meiying Kuai James H.Clark Tao Tu Jiangsu Co-Innovation center of Efficient Processing and Utilization of Forest resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China Circa renewable Chemistry Institute Green Chemistry Centre of ExcellenceUniversity of YorkYork YO105DDUnited Kingdom Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200433China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Green Catalysis center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Asymmetric catalysis has been one of the most effective strategies for building up a chirality in the favored stereoisomer. Over the past decades, various sophisticated chiral ligands and catalysts have been well-designed, which enable great advances in enantioselective chemical transformations, for achieving excellent selectivity and activity.

关键词： chiral substituted applicable

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WIND ENERGY MAP OF ARABIAN GULF

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Natural resources 2018年第5期9卷 212-228页

作者： Khaled Al-Salem Subramaniam Neelamani Waleed Al-Nassar Coastal Management Program Environment and Life Sciences Research Center Shuwaikh Kuwait renewable Energy Program Energy and Building Research Centre Shuwaikh Kuwait

Wind power is not only pollution free and renewable but is becoming more economical with technology development. The countries around the Arabian Gulf region are investing for wind powers both the land and in their marine space. A detailed study on wind power resource in the Arabian Gulf is not available. This paper is on the wind energy resource availability over Arabian Gulf waters, covering 2300 grid points. The data available with Coastal Information System data base at Kuwait Institute for Scientific Research, Kuwait, from 1979 to 2015 is used. The probability density and power density were derived from these data source. Weibull probability density function has been fitted to the wind speed data and the wind power density was evaluated. The study is carried out at 10 m, 30 m and 50 m elevations. The central location of the Arabian Gulf has higher annual average wind speed, ranging from 6 to 8 m/s at 10 m elevation, 7 to 8 m/s at 30 m elevation and 8 to 9 m/s at 50 m elevation. The scale parameter “c” at central location of Arabian Gulf is found to range from 6 - 8 m/s for 10 m elevation, 7 - 8 m/s for 30 m elevation and 8 - 9 m/s for 50 m above sea level. The Weibull shape parameter k varies from 2.5 to 3 at the north and central of the Arabian Gulf. The annual mean wind power density over Arabian Gulf Waters is the highest in the central region of the Gulf. The power density at 10 m, 30 m and 50 m hub height varies between 200 to 300 w/m2, 200 to 300 w/m2 and more than 300 w/m2 respectively. It is attractive to install large scale wind power generation at the central region of the Arabian Gulf and at elevations of 30 m or 50 m, since this region lies in Class 2 category of the Wind Energy Resource Atlas of the United States. The wind power density is attractive especially in summer season around the central region location in Arabian Gulf (Saudi Arabia, Bahrain and Qatar), since high rate of power is used for air conditioning systems in summer.

关键词： Wind Energy Arabian Gulf Weibull Distribution Gulf Cooperation Council Kuwait

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Comparison of changes in deltaic development of the Mississippi and Yellow Rivers

Comparison of changes in deltaic development of the Mississi...

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黄河流域资源环境与生态文明建设学术研讨会

作者： Timothy Rosen 许学工胥毅军 School of renewable Natural resources Louisiana State University and Agricultural Center Baton RougeLouisiana 70803USA College of Urban and Environmental sciences Peking University Beijing 100871P.R.China

＜正＞Delta development is controlled by river power,sediment transport,and near-shore hydrodynamic *** a natural state,equilibrium can be reached between these different forces,creating a temporal stable although dynamic ***, the natural state of many river deltas has been experiencing anthropogenic disturbances, such as dam construction,channel modification,and intensive land use in the drainage basins,leading to changes in riverine sediment transport,deposition,distribution,and deltaic *** of the most engineered rivers in the world are the Mississippi/Atchafalaya River system in the United States and the Yellow River

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The current phosphate recycling situation in China and Germany:a comparative review

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Frontiers of Agricultural Science and Engineering 2019年第4期6卷 403-418页

作者： Qing XUE Xinyue HE Saskia D.SACHS Gero C.BECKER Tao ZHANG Andrea KRUSE Institute of Agricultural Engineering Conversion Technologies of Biobased ResourcesUniversity of Hohenheim70599 StuttgartGermany Biomass Engineering center Beijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationKey Laboratory of Plant-Soil Interactions of Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Phosphorus(P)is an indispensable element for organisms but the primary source of P-mineral phosphate resources-are *** production has a high demand for fossil phosphate resources,but the resulting phosphate-rich residues are lack of *** leads to rapid reserves depletion and severe phosphate pollution *** sustainable way is to reuse the phosphate dispersed in various residues such as sewage sludge and livestock *** techniques have emerged to recover phosphate from wastes to close the phosphate *** it is a global issue,the regional situations regarding potential phosphate scarcity and its management differ *** is rich in phosphate resources,but over-exploitation has greatly increased the risk of phosphate rocks depletion,while in Germany the P resources depend on imports,but there is commitment to keep a balance between import and *** had led to great differences in the way the two countries deal with the"re-use"of phosphate in *** is now in a transition phase from the simple terminal pollution control to"waste"reuse and nutrient resources *** sign of this tendency is the mandatory garbage classification and preparation for further processing and *** was first implemented in Shanghai in 2019,whereas Germany has been following the legal framework for waste management since the 19 th *** are a series of laws to control the nutrient loss from municipal and agricultural activities,as for instance with sewage sludge ordinance and fertilizer *** of these laws have been newly revised *** sludge cannot be directly utilized on farmland as organic fertilizer any ***,phosphate and other nutrients should be recovered from sewage *** phosphate recovery technologies and related nutrient recycling schemes are *** review summarizes the current situation of phosphate-containing residues management and

关键词： phosphate recovery manure sewage sludge ordinances technologies

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A k-mer-based pangenome approach for cataloging seed-storage-protein genes in wheat to facilitate genotype-to-phenotype prediction and improvement of end-use quality

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Molecular Plant 2024年第7期17卷 1038-1053页

作者： Zhaoheng Zhang Dan Liu Binyong Li Wenxi Wang Jize Zhang Mingming Xin Zhaorong Hu Jie Liu Jinkun Du Huiru Peng Chenyang Hao Xueyong Zhang Zhongfu Ni Qixin Sun Weilong Guo Yingyin Yao Frontiers Science center for Molecular Design Breeding Key Laboratory of Crop Heterosis and Utilization(MOE)and Bejing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing100193China Key Laboratory of Crop Gene resources and Breeding Institute of Crop ScienceChinese Academy of Agricultural SciencesBejingChina

Wheat is a staple foodfor more than 35%of the world's population,with wheatflourused to make hundreds of baked *** end-use quality is a major breeding target;however,improving it is especially time-consuming and ***,genes encoding seed-storage proteins(ssPs)form multigene families and are repetitive,with gaps commonplace in several genome *** overcome these barriers and efficiently identify superior wheat SSP alleles,we developed"PanSK"(Pan-SSP k-mer)for genotype-to-phenotype prediction based on an SsP-based pangenome *** uses 29-mer sequences that represent each ssP gene at the pangenomic level to reveal untapped diversity across landraces and modern ***-wide association studies with k-mers identified 23 Ssp genes associated with end-use quality that represent novel targets for *** evaluated the effect of rye secalin genes on end-use quality and found that removal of w-secalins from 1BL/1RS wheat translocation lines is associated with enhanced end-use ***,using machine-learning-based prediction inspired by PanSK,we predicted the quality phenotypes with high accuracy from genotypes *** study provides an effective approach for genome design based on ssP genes,enabling the breeding of wheat varieties with superior processing capabilities and improved end-use quality.

关键词： wheat seed-storage protein end-use quality k-mer pangenome genomic prediction

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Achieving highly selective electrochemical CO_(2) reduction to C_(2)H_(4) on Cu nanosheets

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Journal of Energy Chemistry 2023年第4期79卷 312-320页

作者： Huan Xie Ruikuan Xie Zhiyuan Zhang Yongyu Pang Yuting Luo Jiong Li Bilu Liu Maria-Magdalena Titirici Guoliang Chai State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina Jiangsu Co-Innovation center of Efficient Processing and Utilization of Forest resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037JiangsuChina Shenzhen Geim Graphene center(SGC) Tsinghua-Berkeley Shenzhen Institute(TBSI)and Tsinghua Shenzhen International Graduate School(TSIGS)Tsinghua UniversityShenzhen 518055GuangdongChina School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Department of Chemical Engineering Imperial College LondonSW72AZUK

The conversion of CO_(2)into value-added chemicals coupled with the storage of intermittent renewable electricity is *** nanosheets with an average size and thickness of~30 and~20 nm have been developed,which are in situ reduced into Cu nanosheets during electrochemical CO_(2)reduction reaction(ECO_(2)RR).The derived Cu nanosheets demonstrate much higher selectivity for C2H4production than commercial CuO derived Cu powder,with an optimum Faradaic efficiency of 56.2%and a partial current density of C_(2)H_(4)as large as 171.0 mA cm^(-2)in a gas diffusion flow *** operando attenuated total reflectance-Fourier transform infrared spectra measurements and density functional theory simulations illustrate that the high activity and selectivity of Cu nanosheets originate from the edge sites on Cu nanosheets with a coordinate number around 5(4–6),which facilitates the formation of^(*)CHO rather than^(*)COH intermediate,meanwhile boosting the C-C coupling reaction of^(*)CO and^(*)CHO intermediates,which are the critical steps for C_(2)H_(4)formation.

关键词： Electrochemical CO_(2)reduction Cu nanosheets C_(2)H_(4) High selectivity Coordination number

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