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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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Mathematical theory of signal analysis vs. complex analysis method of harmonic analysis

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Applied Mathematics(A Journal of Chinese Universities) 2013年第4期28卷 505-530页

作者： QIAN Tao zhang li-ming Department of Mathematics University of Macao Macao Department of Computer and Information Science University of Macao Macao

We present recent work of harmonic and signal analysis based on the complex Hardy space approach.

关键词： Mobius transform Blaschke form mono-component Hardy space adaptive Fourier decomposi-tion rational approximation rational orthogonal system time-frequency distribution digital signal processing,uncertainty principle higher dimensional signal analysis in several complex variables and the Clifford algebrasetting.

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Simultaneous Determination of Magnolol and Honokiol by Synchronous Fluorescence Spectroscopy

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Chinese Chemical Letters 2006年第12期17卷 1603-1606页

作者： Min zhang li ming DU Analytical and Testing Center Shanxi Normal University Linfen 041004

A simple sensitive and quick assay for simultaneously determining magnolol （MOL） and honokiol （HOL） has been described based on their natural fluorescence. This method is based on the fact that synchronous fluorometry could resolve the overlapping of fluorescence spectra, which was aroused by their similar molecular structures. In this work, the synchronous spectrum, maintaining a constant difference of Aλ =10 nm between the emission and excitation wavelengths, has been selected for the determination of HOL and MOL. Under the optimum conditions, the fluorescence intensity is proportional to the concentration of MOL and HOL in solution over the range 0.075-0.7 μg/mL and 0.05-0.9 μg/mL with the detection limit of 0.029 μg/mL and 0.019 μg/mL, respectively. The method was applied to the simultaneous determination of MOL and HOL in pharmaceutical dosage with satisfactory results.

关键词： Magnolol honokiol synchronous fluorometry.

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Adaptive control method for nonlinear time-delay processes

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Journal of Systems Engineering and Electronics 2007年第3期18卷 566-576页

作者： Chen Zonghai zhang Haitao li ming Xiang Wei Dept of Automation Univ of Science and Technology of China Hefei 230027 P R China

Two complex properties, varying time-delay and block-oriented nonlinearity, are very common in chemical engineering processes and not easy to be controlled by routine control methods. Aimed at these two complex properties, a novel adaptive control algorithm the basis of nonlinear OFS （orthonormal functional series） model is proposed. First, the hybrid model which combines OFS and Volterra series is introduced. Then, a stable state feedback strategy is used to construct a nonlinear adaptive control algorithm that can guarantee the closed-loop stability and can track the set point curve without steady-state errors. Finally, control simulations and experiments on a nonlinear process with varying time-delay are presented. A number of experimental results validate the efficiency and superiority of this algorithm.

关键词： adaptive control block-oriented nonlinearity varying time-delay OFS Volterra Series,

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Thermal Characterization and Decomposition Kinetics of Free Anthraquinones from Rhubarb

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Chinese Chemical Letters 2006年第5期17卷 699-702页

作者： li ming zhang Xia li Yu Jie DAI College of Bioengineering Tianjin University of Science ＆ Technology Tianjin 300222

The thermal behaviour of aloe-emodin, chrysophanol and physcion and their kinetics have been investigated under non-isothermal conditions by means of differential thermal analysis （DTA） and thermogravimetry （TG）. The thermal characteristics have been determined using the DTA and TG-DTG curves. The non-isothermal kinetic data were analyzed by means of the Achar method and the Madhusudanan-Krishnan-Ninan （MKN） method. The possible reaction mechanisms have been investigated by comparing the kinetic parameters. The kinetic equation for aloe-emodin, chrysophanol and physcion can be expressed as dα/dt=Aexp（-E/RT）1/3（1-α）[-In（1-α]2. The activation energy E （kJ mol^-1） of the three free anthraquinones are 78.09, 89.54, and 107.5 and their InA/s^-1 are 22.98, 36.85 and 43.60, respectively.

关键词： Aloe-emodin chrysophanol physcion thermogravimetry (TG) differential thermoanalysis (DTA) non-isothermal kinetics.

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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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Mathematic Model of SEN Clogging During Continuous Casting of Steel

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Journal of Iron and Steel Research International 2010年第8期17卷 6-9页

作者： WU Su-zhou zhang Jiong-ming li Zhi-zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The SEN clogging is a serious problem for continuous casting operation and steel *** kinetics mathematic model of SEN clogging during steel continuous casting is *** fluid flow and inclusions motion are calculated by means of mathematic *** of diameters of inclusions,roughness of nozzle,diameter of nozzle and casting speed on the entrapment probability are calculated and *** result shows that inclusions are more easily to attach to the nozzle by the following condition：smaller inclusion size,larger roughness of the wall and the smaller bulk velocity in the nozzle.

关键词： nozzle clogging mathematic model inclusion motion

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Thermal dynamics of the permafrost active layer under increased precipitation at the Qinghai-Tibet Plateau

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Journal of Mountain Science 2019年第2期16卷 309-322页

作者： li De-sheng WEN Zhi CHENG Qian-gong XING Ai-guo zhang ming-li li An-yuan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environmental and ResourcesCAS Department of Geological Engineering Southwest Jiaotong University Department of Civil Engineering Lanzhou University of Technology Department of Civil Engineering Shaoxing University

Precipitation has a significant influence on the hydro-thermal state of the active layer in permafrost regions, which disturbs the surface energy balance, carbon flux, ecosystem, hydrological cycles and landscape processes. To better understand the hydro-thermal dynamics of active layer and the interactions between rainfall and permafrost, we applied the coupled heat and mass transfer model for soil-plant-atmosphere system into high-altitude permafrost regions in this study. Meteorological data, soil temperature, heat flux and moisture content from different depths within the active layer were used to calibrate and validate this model. Thereafter, the precipitation was increased to explore the effect of recent climatic wetting on the thermal state of the active layer. The primary results demonstrate that the variation of active layer thickness under the effect of short-term increased precipitation is not obvious, while soil surface heat flux can show the changing trends of thermal state in active layer, which should not be negligible. An increment in year-round precipitation leads to a cooling effect on active layers in the frozen season, i.e. verifying the insulating effect of "snow cover". However, in the thawed season, the increased precipitation created a heating effect on active layers, i.e. facilitating the degradation of permafrost. The soil thermal dynamic in single precipitation event reveals that the precipitation event seems to cool the active layer, while compared with the results under increased precipitation, climatic wetting trend has a different influence on the permafrost evolution.

关键词： Active layer Precipitation Qinghai-Tibet plateau Hydro-thermal dynamic

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Mechanisms of Enhanced Rice Growth and Nitrogen Uptake by Nitrate

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Pedosphere 2007年第6期17卷 697-705页

作者： DUAN Ying-Hua YIN Xiao-ming zhang Ya-li SHEN Qi-Rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Rice is being increasingly cultivated in intermittently irrigated regions and also in aerobic soil in which Nitrate （NO3^- ） plays important role in nutrition of plant. However, there is no information regarding the influence of nitrate on the overall growth and uptake of nitrogen （N） in rice plant. Solution culture experiments were carried out to study the effects of NO^3- on the plant growth, uptake of N, and uptake kinetics of NH4^＋ in four typical rice （Oryza sativa L.） cultivars （conventional indica, conventional japonica, hybrid indica, and hybrid japonica）, and on plasma membrane potential in roots of two conventional rice cultivars （indica and japonica） at the seedling stage. The results obtained indicated that a ratio of 50/50 NH4^＋-N/NO3^--N increased the average biomass of rice shoots and roots by 20% when compared with that of 100/0 NH4^＋-N/NO3^--N. In case of the 50/50 ratio, as compared with the 100/0 ratio, total N accumulated in shoots and roots of rice increased on an average by 42% and 57%, respectively. Conventional indica responds to NO3^- more than any other cultivars that were tested. The NO^3- supply increased the maximum uptake rate （Vmax） of NH4^＋ by rice but did not show any effect on the apparent Michaelis-Menten constant （Km） value, with the average value of Vmax for NH4^＋ among the four cultivars being increased by 31.5% in comparison with those in the absence of NO3^-. This suggested that NO3^- significantly increased the numbers of the ammonium transporters. However, the lack of effect on the Km value also suggested that the presence of NO3^- had no effect on the affinity of the transporters for NH4^＋. The plasma membrane potential in the roots of conventional indica and japonica were greatly increased by the addition of NO3^- , suggesting that NO3^- could improve the uptake of N by roots of the rice plant. In conclusion, the mechanisms by which NO3^- enhances the growth and N uptake of rice plant was found by the increased value of Vm

关键词： ammonium uptake nitrate nutrition nitrogen uptake plasma membrane potential rice

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Accumulation and Gene Expression of Anthocyanin in Storage Roots of Purple-Freshed Sweet Potato [Ipomoea batatas (L.) Lam] Under Weak light Conditions

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Agricultural Sciences in China 2010年第11期9卷 1588-1593页

作者： HOU Fu-yun WANG Qing-mei DONG Shun-xu li Ai-xian zhang Hai-yan XIE Bei-tao zhang li-ming Crop Research Institute Shandong Academy of Agricultural SciencesJinan 250100P.R.China

Anthocyanidin in plants, an important pigment, is of great interest to researchers, consumers, and commercial entities due to its physiological functions. Anthocyanin content and mRNA levels of anthocynin biosynthesis genes were investigated in storage root of different purple-fleshed sweet potatoes (PFSP) genotypes to understand the regulation mechanism of anthocyanin under weak light conditions. Anthocyanin content, its amount of accumulation, and the expression of CHS, DFR, F3H, GT, and ANS genes in the PFSP storage root under weak light conditions were studied. The results demonstrated that the anthocyanin content of the treatments was decreased and was obviously lower than that of the control until 30 days after shading in Ayamurasaki, while it was lower than that of the control from the beginning of shading in Jishu 18. Their accumulation rates of both treatmeants were lower than its control before 10-20 d of shading in Jishu 18, while those of Ayamurasaki weren't in their treatments. This indicated that Jishul 8 is more sensitive to light as compared to Ayamuraska. Under the different weak light conditions, mRNA levels for ibCHS, ibF3H, ibDFR, and ibANS were obviously decreased, while the expression of ibGT was increased. These results indicated that anthocyanin content was regulated by light at the mRNA levels and the enzymatic level in sweet potato. Therefore, the development dynamic response to anthocyanin content varied in different genotypes of PFSP, and mRNA levels of anthocyanin biosynthesis were inhibited under the weak light condition.

关键词： anthocynin sweet potato storage root weak light

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