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Phosphorus accumulation and eutrophication in feed-supply freshwater fishponds

Journal of Environmental Sciences 2006年第4期18卷 816-821页

作者： ZHANG Ming-kui fang Li-ping Institute of Soil and Water Resources and Environmental Science College of Natural Resource and Environmental Sciences Zhejiang UniversityHangzhou 310029 China

The rapid growth and intensification of freshwater fishery can cause imbalances between phosphorus （P） input in feed and its output in produce. This aquaculture can result in enriching exogenous P in fishponds and, consequently, accelerates the process of eutrophication. To assess relations among input, accumulation, release of P and as a consequence degrading water quality in terms of chlorophyll-a （Chl-a） in freshwater fishponds, fourteen fishponds with feed supply, nine fishponds without feed supply, and five nonfish ponds in Shaoxing Plain, southeast China were selected for comparing P accumulation in their waters and surface sediments. Surface sediment samples were collected from each pond to evaluate their total P, water soluble P, Olsen P, algal available P, and P fractions. Water samples were also collected from the ponds to measure concentrations of dissolved P and Chl-a. Total P in the sediments ranged from 0.88 to 1.73 g/kg in the fishponds with feed supply, that in the non-fish ponds ranged from 0.47 to 0.86 g/kg. Organic P, accounted for 23% to 60% of total P in the sediments, was an important P fraction and increased linearly with increasing organic matter. Long-term application of feeds resulted in increased P availability in the bottom sediments and degradation of water quality in the freshwater fishponds. Compared with non-fish ponds, sediments from the feed-supplied fishponds contained considerably higher Olsen P, algal available P, and water soluble P. Higher proportions of the labile P （NH4Cl-P） and potentially labile P （NaOH-IP） were also found in the sediments from the fishponds. High solubility of P in the sediments resulted in elevation of P and chlorophyll-a concentration in the pond water. The dissolved P concentration in the pond water increased in the order of non-fish ponds （12μg/L）〈 fishponds without feed supply （24 μg/L）〈 fishponds with feed supply （66 μg/L）. Linear correlations between concentrations of total P, Olsen-P, algal avail

关键词： eutrophication freshwater fishery phosphorus fraction water quality

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Competitive adsorption and mobility sequence of heavy metals in urban soils of southeastern China

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Journal of Environmental Sciences 2006年第2期18卷 329-333页

作者： ZHANG Ming-kui fang Li-ping HUANG Chang-yong Department of Natural Resource Sciences College of Natural Resource and Environmental Sciences Zhejiang University Hangzhou 310029 China

Heavy metals can be introduced into urban soils at the same time. Therefore, their selective retention and competitive adsorption by the soils become of major importance in determining their availability and movement throughout the soil. In this study, the availability and mobility of six heavy metals in eight urban soils collected from different cities of Zhejiang Province, southeastern China were assessed using distribution coefficients（Kd） and retardation factor（Rf）. The results showed that there were great differences in the Kd and Rfamong the tested soils. The adsorption sequences were Cr〉Pb〉Cu〉Cd〉Zn〉Ni, and the Kd decreased with increasing levels of metal addition. Ni generally has the lowest Rf values followed closely by Cd, and Zn whereas Cr and Pb reached the highest values. The results suggest that Ni and Zn have the highest mobility associated to the lowest adsorption, Cr and Pb present the opposite behavior. Correlation analysis indicates that soil pH, CaCO3 content, and cation exchange capacity （CEC） are key factors controlling the solubility and mobility of the metals in the urban soils.

关键词： competitive adsorption mobility sequence heavy metal urban soil

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Formation and thermal stability of amorphous Ni-Mo-P alloys

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中国有色金属学会会刊：英文版 2004年第z1期14卷 147-151页

作者： ZHANG Yi MA Jun fang Yong-kui DUAN Ji-guo School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China

The experimental researches on the chemical deposition of Ni-Mo-P amorphous alloys were carried out by adding Na2 MoO4 into acidic solutions. The optimum technology conditions were obtained by orthogonal design experiments. The structures and the relationship between compositions and their thermal stability were studied by energy spectrum (EC), scanning electron micrograph and X-ray diffraction spectrum. Compared with Ni-P amorphous alloys, the Ni-Mo-P amorphous alloys have high crystallization temperature and thermal stability, and the hardness reaches its peak when the annealing temperature is 500 ℃. With the increase of the heat treatment temperature, the surface morphology of the alloys changes.

关键词： chemical deposition Ni-Mo-P alloy amorphous phase crystallization

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(G^2-continuous) SHAPE PRESERVING CUBIC INTERPOLATION SPLINE CURVE

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国防科技大学学报 1995年第3期17卷 65-69页

作者： fang kui(Department of System Engineering and Mathematics, NUDT, Changsha,410073)

（Ｇ~２－ｃｏｎｔｉｎｕｏｕｓ）ＳＨＡＰＥＰＲＥＳＥＲＶＩＮＧＣＵＢＩＣＩＮＴＥＲＰＯＬＡＴＩＯＮＳＰＬＩＮＥ　ＣＵＲＶＥＦａｎｇＫｕｉ（ＤｅｐａｒｔｍｅｎｔｏｆＳｙｓｔｅｍＥｎｇｉｎｅｅｒｉｎｇａｎｄＭａｔｈｅｍａ... 详细信息

（Ｇ~２－ｃｏｎｔｉｎｕｏｕｓ）ＳＨＡＰＥＰＲＥＳＥＲＶＩＮＧＣＵＢＩＣＩＮＴＥＲＰＯＬＡＴＩＯＮＳＰＬＩＮＥ　ＣＵＲＶＥＦａｎｇＫｕｉ（ＤｅｐａｒｔｍｅｎｔｏｆＳｙｓｔｅｍＥｎｇｉｎｅｅｒｉｎｇａｎｄＭａｔｈｅｍａｔｉｃｓ，ＮＵＤＴ，Ｃｈａｎｇｓｈ?..

关键词： G^2-连续插值样条曲线

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A New Practical Approach for Procedurally Representing Lofted Surface

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计算机工程 1994年第S1期20卷 496-499页

作者： fang kui (National University of Defense Technology 410073)

Fitting a surface using geometric information (for example: an arbitrary set of 3D curves) is a useful method for comstructing complex surfaces. Tensor-product B-splines usually is used to constructe so-called lofted surfaces and most other types of surfaces in CAD, but several problems must be overcome if B-spline are to represent complex lofted surfaces[1]. We describe a practical approach by using an approximating Hermite type of surface, the construction of the surface is easy. Finally, a lofted surface model is given.

关键词： overcome approximating arbitrary spline CAGD parametric Bezier NURBS cubic offset

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Heteropolytungstates Containing Organotin and Cobalt or Zinc Atom

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Chemical Research in Chinese Universities 1999年第4期15卷 317-321页

作者： WANG Xiao-hong fang Xi-kui LIU Jing-fu Department of Chemistry Northeast Normal UniversityChangchun 130024P.R.China

Organotin substituted heteropolytungstates with cobalt or zinc atom as the central atom, \{K 6H[XW 11 O 39 (RSn)]\}· n H 2O(X=Zn, Co; R=CH 3OOCCH 2CH 2, CH 2OOCCH(CH 3)CH 2, NCCH 2CH 2) were prepared and characterized by elemental analysis, IR, UV Vis spectroscopy, ESR, NMR spectroscopy and electrochemical study. The results show that these anions possess Keggin like structures.

关键词： Organotin Transition metal Heteropolyanion

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Hydrogen induced cracking of X80 pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 579-586页

作者： Chao-fang Dong kui Xiao Zhi-yong Liu Wen-jing Yang Xiao-gang Li Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

The hydrogen-induced cracking （HIC） behavior of X80 pipeline steel was studied by means of electrochemical charging, hydrogen permeation tests, tension test, and scanning electron microscopy （SEM）. The experimental results indicate that the increase of charging time and charging current density or the decrease of the solution pH value leads to an increase of the hydrogen content in X80 steel, which plays a key role in the initiation and propagation of HIC. It is found that the majority of macro-inclusions within the as-used X80 steel do not constitute a direct threat to HIC except aluminum oxides, which directly or indirectly lead to HIC. The hydrogen trap density at room temperature is estimated to be pretty high, and this is an essential reason why the steel is sensitive to HIC. After hydrogen charging, the elongation loss rate and area reduction of X80 steel decline obviously, taking a noticeable sign of hydrogen-induced plasticity damages. It is demonstrated that the losses of these plastic parameters have a linear relation to the fracture size due to hydrogen.

关键词： pipeline steel hydrogen induced cracking electrochemical charging fracture

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Glucose-conjugated chitosan nanoparticles for targeted drug delivery and their specific interaction with tumor cells

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Frontiers of Materials Science 2014年第4期8卷 363-372页

作者： Jing LI fang-kui MA Qi-Feng DANG Xing-Guo LIANG Xi-Guang CHEN College of Food Science and Engineering Ocean University of China Qingdao 266003 China Freshwater Fisheries Research Institute of Shandong Province Jinan 250013 China College of Marine Life Science Ocean University of China Qingdao 266003 China

A novel targeted drug delivery system, glucose-conjugated chitosan nanoparticles （GCNPs）, was developed for specific recognition and interaction with glucose transporters （Gluts） over-expressed by tumor cells. GC was synthesized by using succinic acid as a linker between glucosamine and chitosan （CS）, and successful synthesis was confirmed by NMR and elemental analysis. GCNPs were prepared by ionic crosslinking method, and characterized in terms of morphology, size, and zeta potential. The optimally prepared nanoparticles showed spherical shapes with an average particle size of （187.9 ± 3.8） nm and a zeta potential of （-15.43 ± 0.31） mV. The GCNPs showed negligible cytotoxicity to mouse embryo fibroblast and 4T1 cells. Doxorubicin （DOX） could be efficiently entrapped into GCNPs, with a loading capacity and encapsulation efficiency of 20.11% and 64.81%, respectively. DOX-Ioaded nanoparticles exhibited sustained-release behavior in phosphate buffered saline （pH 7.4）. In vitro cellular uptake studies showed that the GCNPs had better endocytosis ability than CSNPs, and the antitumor activity of DOX/GCNPs was 4-5 times effectiveness in 4T1 cell killing than that of DOX/CSNPs. All the results demonstrate that nanoparticles decorated with glucose have specific interactions with cancer cells via the recognition between glucose and Gluts. Therefore, Gluts-targeted GCNPs may be promising delivery agents in cancer therapies.

关键词： drug delivery target nanoparticle glucose transporter (Glut) chitosan(CS)

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Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with Different Treatment Process

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Biomedical and Environmental Sciences 2018年第8期31卷 632-636页

作者： fang Dao kui ZHOU Guo Hong YU Shu Yuan FENG Jin Shu Institute for Environment and Health Shenzhen Center for Disease Control and Prevention

Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wa... 详细信息

关键词： Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with Different Treatment Process

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Temperature Stress at Grain Filling Stage Mediates Expression of Three Isoform Genes Encoding Starch Branching Enzymes in Rice Endosperm

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Rice science 2009年第3期16卷 187-193页

作者： WEI Ke-su CHENG fang-min ZHANG Qi-fang Liu kui-gang College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China

An early-maturity indica rice variety Zhefu 49, whose grain quality and starch structure are sensitive to environmental temperature, was subjected to different temperatures （32℃ for high temperature and 22℃ for optimum temperature） at the grain filling stage in plant growth chambers, and the different expressions of three isoform genes （SBEI, SBEIII and SBE/V） encoding starch branching enzyme （SBE） in the endosperms were studied by the real-time fluorescence quantitative PCR （FQ-PCR） method. Effects of high temperature on the SBE expression in developing rice endosperrns were isoform-dependent. High temperature significantly down-regulated the expressions of SBEI and SBEIII, while up-regulated the expression of SBEIV. Compared with SBEIV and SBEIII, the expression of SBEI gene in Zhefu 49 rice endosperms was more sensitive to temperature variation at the grain filling stage. This study indicates that changes in weather/climate conditions especially temperature stress influence rice grain formation and its quality as evidenced by isoform expression.

关键词： rice high temperature starch branching enzyme isoform gene expression real-time fluorescence quantitative PCR rice quality

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