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Spatiotemporal optical properties of dissolved organic matter in a sluice-controlled coastal plain river with both salinity and trophic gradients

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Journal of Environmental Sciences 2023年第7期129卷 1-15页

作者： yu Liu yucheng Hu Chengxun yu yuqi Gao Zhenying Liu Khan M.G.Mostofa Siliang Li yumei Hu guanghui yu School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China Tianjin Hydraulic Science Research Institute Tianjin 300061China School of Environmental Science and Safety Engineering Tianjin University of TechnologyTianjin 300191China School of Mathematics Tianjin UniversityTianjin 300072China

Due to the combined effect of sluices and sea tide,the sluice-controlled coastal plain river would be characterized by both trophic state and salinity gradients,affecting the spatiotemporal optical properties of dissolved organicmatter(DOM).In this study,we investigated the spatiotemporal variation of water quality parameters and optical properties of DOM in the Haihe River,a representative sluice-controlled coastal plain river in Tianjin,China.A significant salinity gradient and four trophic states were observed in the water body of the Haihe *** humic-and one protein-like substances were identified from the DOM by the three-dimensional fluorescence spectra combined with the parallel factor(PARAFAC)***’s correlation analysis and redundancy analysis(RDA)showed that the salinity significantly affected the abundance of chromophoric DOM(CDOM)but did not cause significant changes in the fluorescence optical *** addition,the effect of Trophic state index(TSI)on the CDOM abundance was greater than that on the fluorescence intensity of fluorescent dissolved organic matter(FDOM).In the water body with both salinity and trophic state gradients,TSI posed a greater influence than salinity on the CDOM *** results fill the research gap in spatiotemporal DOM characteristics and water quality variation in water bodies with both salinity and trophic state *** results are beneficial for clarifying the joint influence of saline intrusion and sluices on the DOM characteristics and water quality in sluice-controlled coastal plain rivers.

关键词： Dissolved organic matter Optical characteristics Trophic state index Salinity gradient Haihe River Sluice-controlled coastal plain river

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Hybrid Phase-controlled Circuit Breaker with Switch System Used in the Railway Auto-passing Neutral Section with an Electric Load

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CSEE Journal of Power and Energy Systems 2019年第4期5卷 545-552页

作者： Shuo Wang Liyan Zhang guanghui yu Enyuan Dong Jiyan Zou yu Cong yu Tian School of Electrical Engineering Dalian University of TechnologyDalian 116024China Dalian Electric Power Supply Company Dalian 116000China

Constrained by the characteristics of neutral sec- tions (NS) and traditional vacuum circuit breakers, previous phase-controlled strategies have a long power supply dead time, it is difficult to realize a continuous power supply to the auxiliary power system. The dead time can be reduced by using the ground automatic convert method, hybrid phase-controlled technologies can in theory completely eliminate inrush currents. In this paper, a new system based on hybrid phase-controlled switches is described and termed ground-switching passing neutral section system (GPNSS). The principle for restraining inrush currents is analyzed and strategies are carried out with the dead time limited to 5 ms. The characteristics of the vacuum circuit breaker are illustrated and the closing time window of the transformer is quantified. Through the use of mechanical switches and power electronics, the auxiliary power system may be continuously pow- ered. The prototype system is implemented and experimentally tested in the laboratory.

关键词： Automatic system hybrid circuit breaker inrush current neutral section phase-controlled technology

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Meta-analysis in the production chain of aquaculture: A review

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Information Processing in Agriculture 2022年第4期9卷 586-598页

作者： guanghui yu Chunhong Liu Yingying Zheng Yingyi Chen Daoliang Li Wei Qin National Innovation Center for Digital Fishery China Agricultural UniversityChina Beijing Engineering and Technology Research Centre for Internet of Things in Agriculture China Agriculture University Beijing 100083China Precision Agricultural Technology Integration Research Base(Fishery) Ministry of Agriculture and Rural AffairsChina Key Laboratory of Agricultural Information Acquisition Technology Ministry of AgricultureChina Agriculture UniversityBeijing 100083China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Biological Engineering Utah State UniversityLoganUT 84341United States

Meta-analysis is a statistical analysis of the data obtained from multiple studies and pro-vides a quantitative synthesis of research *** can be a key tool for facilitating rapid progress in aquaculture by quantifying what is known and identifying what is not yet ***,due to the complexity of the environment and problems associated with the use of model in aquaculture,it remain few guidelines for the design,implementation or interpretation of meta-analysis in the field of ***,we first briefly reviewed the history of meta-analysis,then summarized the applications of meta-analysis in terms of major procedures,standards,and ***,we critically reviewed the results of meta-analysis studies in the production chain of aquaculture and identified the potentials for improving yield in both quantity and ***,there is a large room for improving yield along the production *** contributions can be found in breeding,feed,and farm *** example,improving breeding can increase yield by 5.6%to 49%,depending on fish species and type of *** study revealed large potentials for improving yield in the production chain of aquaculture and summarized the application of meta-analysis in *** recommendations of standardizing and improving meta-analysis in aquaculture were proposed.

关键词： Aquaculture Quantitative analysis Meta-analysis Production

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Numerical investigation for effects of natural light and ventilation on 3D tomato body heat distribution in a Venlo greenhouse

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Information Processing in Agriculture 2023年第4期10卷 535-546页

作者： guanghui yu Shanhong Zhang Shuai Li Minshu Zhang Hüseyin Benli Yang Wang National Innovation Center for Digital Fishery China Agricultural UniversityBeijing 100083China Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsChina Agricultural University100083BeijingChina Engineering and Technology Research Center for Internet of Things in Agriculture China Agricultural University100083BeijingChina College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Department of Technical and Vocational Education Firat UniversityTR-23119 ElazigTurkey for Huseyin Benli

Maintaining suitable temperature level around tomato in the greenhouse is essential for the high-quality ***,in summer,the temperature level around the tomato is usually unclear except using a high-precision temperature *** solve this problem,thermal performance of 3D(three-dimensional)tomato model built based on SolidWorks was investigated by the computational fluid dynamics(CFD)*** assess the effect of temperature distribution around the tomato,a simplified 3D tomato numerical model was firstly validated by a set of field measurement *** light intensity and indoor ventilation were regarded as the mainly environment factors in the Venlo greenhouse,thermal stratification around tomatoes at different time of day was further *** numerical results illustrated the different temperature distribution around tomato body under different radiation *** was found that ventilation could obviously adjust the temperature gradient around the tomato,and alleviate high temperature effect particularly in *** ventilation could create a suitable thermal environment for the tomato *** study clearly demonstrated 3D temperature distribution around tomatoes,which is beneficial to provide the reference for accurate detection of 3D tomato temperature and appropriate thermal environment design.

关键词： CFD 3D Tomato body Heat distribution Greenhouse environment Growth condition

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Forms and Balance of Nitrogen and Phosphorus in Cage Culture Waters in Guangdong Province, China

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Chinese Geographical Science 2007年第4期17卷 370-375页

作者： WEN Yanmao WEI Xiange SHU Tingfei ZHOU Jingfeng yu guanghui LI Feng HUANG Yanyun School of Environmental Science and Engineering SUN Yat-Sen University Guangzhou 510275 China

In order to approach the characteristics of nitrogen and phosphorus pollution caused by cage culture and the balance of nitrogen and phosphorus during the process of cage culture, a monitoring was conducted in Daya Bay of Guangdong Province, China from April 2002 to Jane 2003. The results show that the concentrations of total nitrogen （TN） in the waters at the sites with five and ten years of cage culture history are 1.8 and 2.3 times of that at control site respectively. Ammonium （NH3-N） is the main form of nitrogen in spring while nitrate （NO~） in winter. The concentrations of TN, total dissolved nitrogen （TDN） and dissolved organic nitrogen （DON） are highest in autumn. The concentration of phosphorus increases with the increasing of the culturing time, among which phosphate （ PO^-34） increases most obviously. The concentrations of total phosphorus （TP） and total dissolved phosphorus （TDP） are highest in autumn. The nitrogen and phosphorus are accumulated significantly in the sediment of cage culture area. The model of N balance in the cage culture area： bait （70.62%）＋ fry （0.28%）＋ input by tide （14.8%）＋ release from sediment 04.3%） = harvest of adult fish （12.07%）＋ deposition into sediment （28.75%）＋ output by tide （56.18%）＋ others （3.00%）. The model of P balance： bait （83.11%）＋ fry （0.17%）＋ input by tide （12.23%）＋ release from sediment （4.49%） = harvest of adult fish （8.43%）＋ deposition into sediment （48.59%）＋ output by tide （41.94%）＋ others （1.04%）. In one fish growth year, the contents of nitrogen and phosphorus in harvest of adult fish are only 17.0% and 10.1% of the contents of nitrogen and phosphorus in fish bait and fry, wherein 83% of nitrogen and more than 89% of phosphorus in fish bait became marine pollutants.

关键词： cage culture environment impact nitrogen phosphorus Daya Bay Guangdong Province

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Axially Chiral Dodecanuclear Lanthanide Clusters Constructed by“Bottom-Up” Self-assembly for Enantioselective Sensing

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Chinese Journal of Chemistry 2022年第10期40卷 1165-1170页

作者： Honglei Zhao Dongxu Cui Junning Kou Haijuan Gao guanghui yu Chunyi Sun Xinlong Wang Zhongmin Su Key Laboratory of Polyoxometalate Science of Ministry of Education Northeast Normal UniversityChangchunJilin 130024China

Via the bottom-up synthetic strategy,we synthesized a pair of dodecanuclear metal clusters of Eu_(12)(C_(2)O_(4))_(9)(R/S-BNP)_(18)(EtOH)_(6)-(H_(2)0)_(6)·8EtOH-7H_(2)0(complex 2),which represent the largest axial chiral lanthanide metal *** the structure,rare four-pointed star coordination mode of oxalic acid is reported by this *** addition,as a fluorescence sensor,the complex 2 exhibits high enantioselectivity for R-/S-BINOL-TF_(2)(EF=2.87)and other chiral binaphthyl derivatives.

关键词： Axial chirality Cluster compounds Molecular recognition Self-assembly Host-guest systems

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Spatial-temporal Pattern and Population Driving Force of Land Use Change in Liupan Mountains Region, Southern Ningxia, China

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Chinese Geographical Science 2008年第4期18卷 323-330页

作者： QUAN Bin M J M ROMKENS TAO Jianjun LI Bicheng LI Chaokui yu guanghui CHEN Qichun Institute of Geospatial Information Science Hunan University of Science and Technology Xiangtan 411201 China USDA/ARS National Sedimentation Laboratory P O. Box 1157 Oxford MS 38655 USA Researeh Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of Education Northwest Sci-tech University of Agriculture and Forestry Yangling 712100 China

The Liupan Mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan Mountains region has suffered tremendous ecological damages over time due to population pressure, excessive demand and inappropriate use of agricultural land resources. In this paper, datasets of land use between 1990 and 2000 were obtained from Landsat TM imagery, and then spatial models were used to characterize landscape conditions. Also, the relationship between the population density and land use/cover change (LUCC) was analyzed. Results indicate that cropland, forestland, and urban areas have increased by 44,186ha, 9001ha and 1550ha, respectively while the grassland area has appreciably decreased by 54,025ha in the study period. The decrease in grassland was most notable. Of the grassland lost, 49.4% was converted into cropland. The largest annual land conversion rate in the study area was less than 2%. These changes are attributed to industrial and agricultural development and population growth. To improve the eco-economic conditions in the study region, population control, urbanization and development of an ecological friendly agriculture were suggested.

关键词： land use/cover change (LUCC) GIS remote sensing Liupan Mountains region Loess Plateau

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Importers Drive Leaf-to-Leaf Jasmonic Acid Transmission in Wound-Induced Systemic Immunity

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Molecular Plant 2020年第10期13卷 1485-1498页

作者： Mengya Li Feifei Wang Shuangzhang Li guanghui yu Lijian Wang Qingqing Li Xiangyu Zhu Zhen Li Lixing yuan Pei Liu Department of Ecology College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193P.R.China Department of Plant Nutrition College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193P.R.China

The transmission of mobile wound signals along the phloem pathway is essential to the activation of wound-induced systemic response/resistance,which requires an upsurge of jasmonic acid(JA)in the distal undamaged *** these mobile signals,the electrical signal mediated by the glutamate-dependent activation of several clade three GLUTAMATE RECEPTOR-LIKE(GLR3)proteins is involved in the stimulation of JA production in distal ***,whether JA acts as a mobile wound signal and,if so,how it is transmitted and interacts with the electrical signal remain ***,we show that JA was translocated from the local to distal leaves in Arabidopsis,and this process was predominantly regulated by two phloem-expressed and plasma membrane-localized jasmonate transporters,AtJAT3 and *** addition to the cooperation between AtJAT3/4 and GLR3.3 in the regulation of long-distance JA translocation,our findings indicate that importer-mediated cell-cell JA transport is important for driving the loading and translocation of JA in the phloem pathway in a self-propagating manner.

关键词： wound-induced systemic resistance jasmonate importers mobile signals phloem loading long-distance transmission self-propagation mode

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Oxidation process of lanthanum hexaboride ceramics

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Rare Metals 2002年第2期21卷 101-105页

作者： ZHENG Shuqi, MIN guanghui, ZOU Zengda , yu Huashun, HAN Jiande , and WANG Weiti School of Materials Science and Engineering, Shandong University, Jinan 250061, China School of Materials Science and Engineering Shandong University Jinan 250061

Oxidation process of lanthanum hexaboride (LaB_6) ceramic powderwas investigated. The laB_6 powder sma- ples were heated continuallyfrom room temperature to 1473 K at a heating rate of 10 k/min bydifferential scanning calorimetry. The oxidation tests were conductedat different exposure temeratures. The phases and morphologies of thesamples before and after exposure were analyzed by XRD and SEM. Itwas pointed out that before 1273 K, LaB_6 has high oxidationresistant ability, which was due to that the oxide layer hinders theoxygen diffusion from outer to the sur- face of Lab_6 grains.

关键词： lanthanum hexaboride oxidation mechanism ceramic

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Effect of proteins,polysaccharides,and particle sizes on sludge dewaterability

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Journal of Environmental Sciences 2009年第1期21卷 83-88页

作者： SHAO Liming,HE Peipei,yu guanghui,HE Pinjing State Key Laboratory of Pollution Control and Resources Reuse,Key Laboratory of Yangtze River Water Environment,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China. E-mail: solidwaste@***

Four batch experiments of hydrolysis and acidification were carried out to investigate the distributions of proteins （PN） and polysaccharides （PS） in the sludge, the PN/PS ratio, the particle sizes, and their relationship with sludge dewaterability （as determined by capillary suction time, CST）. The sludge flocs were stratified through centrifugation- and ultrasound-based method into four fractions：（1） slime, （2） loosely bound extracellular polymeric substances （LB-EPS）, （3） tightly bound EPS （TB-EPS）, and （4） pellet. The results showed that PN was mainly partitioned in the pellet （80.7%） and TB-EPS （9.6%） fractions, while PS distributed evenly in the four fractions. During hydrolysis and acidification, PN was transferred from the pellet and TB-EPS fractions to the slime fraction, but PS had no significant transfer trends. The mean particle sizes of the sludge flocs decreased with hydrolysis and acidification. The pH had a more significant influence on the dewaterability of sludge flocs than temperature. Sludge dewaterability during hydrolysis and acidification processes greatly deteriorated from 9.7 s at raw sludge to 340-450 s under alkaline conditions. However, it was just slightly increased under acidic conditions. Further investigation suggested that CST was affected by soluble PN, soluble PN/PS, and particle sizes of sludge flocs, but was affected slightly by total PN, PS, or PN/PS in the whole sludge flocs and other fractions （except slime）.

关键词： dewaterability extracellular polymeric substances particle size polysaccharides proteins sewage sludge

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