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Three-dimensional fluorescence spectral characterization of soil dissolved organic matters in the fluctuating water-level zone of Kai County,Three Gorges Reservoir

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 426-434页

作者： Fang FANG Yan YANG Jinsong GUO Hong ZHOU Chuan FU zhe li Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment of Ministry of Education Chongqing UniversityChongqing 400045China

Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence *** A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like *** E and F,which represent tyrosine-like fluorescence,only appeared in certain *** humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged *** to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water *** of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated *** DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence *** proportion of the content of peak A in soil organic matter was quite *** soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM.

关键词： water-level-fluctuation zone(WLFZ) soil dissolved organic matter(DOM) three-dimensional fluorescence spectra

Molten Steel Flow in a Slab Continuous-casting Tundish

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Journal of Iron and Steel Research International 2014年第S1期21卷 10-16页

作者： liang-cai ZHONG Rui-chao HAO Jun-zhe li Ying-xiong ZHU School of Materials and Metallurgy Northeastern University Key Laboratory for Ecological Utilization of Multi-Metal Intergrown Ores Ministry of Education Northeastern University

Fields of fluid flow and temperature, and residence time distribution(RTD) curves were investigated by mathematical simulation in a one-strand tundish for continuous casting. It was known from the investigation that a big "spring uprush" formed on surface around the long shroud when molten steel flowed into a turbulence inhibitor(TI) with extending lips and rushed up reversely out of the TI, while four small "spring uprushes" existed on surface when a TI without extending lips because the liquid steel flowed mainly out of the 4 corners of the TI. The flow of liquid steel in the former tundish configuration was not reasonable and the height of an area where temperature was less than 1819 K was about half of liquid surface height on the right side of the stopper, which meant that big dead zone existed in the former tundish configuration. In the optimal one, the height of such area was only seventh of the liquid surface height. The RTD curves obtained from the mathematical simulation basically agreed with those from the physical modeling and the flow characteristics obtained from these two methods agreed with each other.

关键词： slab continuous-casting one-strand tundish flow control device molten steel flow mathematical simulation

MC simulation of a PGNAA system for on-line cement analysis

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Nuclear Science and Techniques 2010年第4期21卷 221-226页

作者： YANG Jianbo TUO Xianguo li zhe MU Keliang CHENG Yi MOU Yunfeng State Key Laboratory of Geohazard Prevention & Geoenvironmental Protection Chengdu University of Technology Chengdu 610059 China Nuclear Power Institute of China Chengdu 610005 China China Academy of Engineering Physics Mianyang 621900 China

A prompt gamma neutron activation analysis system with a 252Cf neutron source for on-line cement analysis has been simulated with the MCNP *** results indicate that the optimum arrangement is a Bi shield of 20-mm thickness,a polyethylene moderator of 50-mm thickness,a source-to-sample distance of 70 mm,and cement samples of 1200 mm×600 mm×170 *** absorb thermal neutrons and suppress low-energy γ-rays,the optimum-sized sheets are 150 mm×7 mm Cd,and 150 mm×15 mm Pb.

关键词：水泥化学分析模拟分析系统 PGNAA MC模拟 MCNP程序水泥样品中子活化最佳尺寸

Seasonal variation of nitrogen and phosphorus in Xiaojiang River-A tributary of the Three Gorges Reservoir

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 334-340页

作者： zhe li Jinsong GUO Man LONG Fang FANG Jinping SHENG Hong ZHOU Faculty of Urban Construction&Environmental Engineering Chongqing UniversityChongqing 400045China

A yearlong monitoring program in the backwater area of Xiaojiang River(XBA)was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(TGR)in China,starting after the impoundment water level of the TGR reached 156 *** March 2007 to March 2008,the average concentration of total nitrogen(TN)and total phosphorus(TP)were(1553484)μg·L^(–1)and(6231)μg·L^(–1),*** mean value of chlorophyll was(9.070.91)μg·L^(–1).The trophic level of XBA was meso-eutrophic,while the general nutrient limitation was *** results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial *** variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TP<22.N-fixation from cyanobacteria occurred and became an important process in overcoming the nitrogen deficit under a low TN/TP *** TN/TP≥22,the variation of TP affected the TN/TP ratio more significantly than *** increase of TP in XBA was caused mainly by particulate phosphorus,which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface *** increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.

关键词： Three Gorges Reservoir eutrophication nitrogen phosphorus seasonal variation chlorophyll

Application of multi-source information fusion based on D-S evidence theory in insulation defect identification of DC XLPE cable

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High Voltage 2021年第4期6卷 599-607页

作者： Yongpeng Xu zhe li Guanglei Huang Yong Qian Gehao Sheng Xiuchen Jiang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Shenzhen Power Supply Co. Ltd.ShenzhenChina

During the installation and laying process of cross-linked polyethylene(XLPE)cable,it is difficult to avoid the influence of external harsh environment,which leads to insulation deterioration and *** partial discharge and leakage current play an important role in formation mechanism,characteristic law and identification tech-nology of DC XLPE cable ***,the defect identification accuracy of single source data is *** correlation between partial discharge and leakage current of typical defect is analysed *** on the shape characteristic param-eters of typical DC partial discharge spectrum and the energy characteristic param-eters of leakage current wavelet decomposition node,a weighted Dempster-Shafer(D-S)evidence theory is used to fuse and identify different information *** results show that the classification rate of the proposed method can reach 88%,which can effectively identify insulation defects.

关键词： XLPE insulation defect

Disease and Economic Burden of Kashin-Beck Disease—China,2021

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China CDC weekly 2024年第2期6卷 40-44页

作者： Silu Cui Wenjun Que zhe Jiao Qing Deng Xufeng Zhang Yanhong Cao Ning liu Ailin li Alphonse Sowanou zhe li Tuo Wang Yang li Jun Yu Junrui Pei NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Key Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Kashin-Beck Disease ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Heilongjiang Provincial Key Laboratory of Trace Elements and Human HealthKey Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Endemic Fluorosis ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina

What is already known about this topic?Kashin-Beck disease(KBD)is a chronic and degenerative osteoarthropathy characterized by cartilage *** is an endemic disease that is highly prevalent among the Chinese population and poses a significant health *** is added by this report?This is the first national report on the economic burden of KBD in *** to the data from 2021,KBD has caused significant disease and economic *** most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older,resulting in a total indirect economic burden of 112.74 million Chinese Yuan(CNY).What are the implications for public health practice?The results of this study will contribute to informing the development of tailored prevention and control strategies by the *** strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies,which will be based on the demographic characteristics of the endemic areas.

关键词： prevention degeneration burden

Price Transmission in China's Swine Industry with an Application of MCM

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Journal of Integrative Agriculture 2012年第12期11卷 2097-2106页

作者： XU Shi-wei li zhe-min CUI li-guo DONG Xiao-xia KONG Fan-tao li Gan-qiong Agricultural Information Institute Chinese Academy of Agricultural Sciences (CAAS) Key Laboratory of Agri-Information Service Technology Ministry of Agriculture

The paper studies the relationship, adjustment ability, path, efficiency and intensity of price transmission in the swine industry chain in China, which consists of the prices of corn, compound feed for fattening pig, piglet, pig and pork. Monthly prices covering a period of 18 yr （1994-2011） are analyzed using a Market-Chain Cooperated Model （MCM）. The empirical results show that there exists a stable long-term cointegration and short-term dynamic relationship in the price system. First, the adjustment speed of each price series is very slow and the transmission path is top-down and one-way significantly. Second, the price from upstream to downstream lags about 2 mort, while there is no lag in price transmission from midstream to downstream. Third, in terms of price transmission intensity, the price of pig impacted greatly on pork price, not only in the current period but also through the whole period. Besides, the price of corn has the largest lagged effects on pork price. According to the above empirical results, we suggest that government should strengthen monitoring and early warning of the swine industry chain, especially the upstream and midstream, attach great importance to the timely adjustment of feed prices and perfect the measures of price subsidy.

关键词： price transmission Market-Chain Cooperated Model swine industry chain

Cadmium accumulation in different pakchoi cultivars and screening for pollution-safe cultivars

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Journal of zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第6期13卷 494-502页

作者： Ying CHEN Ting-qiang li Xuan HAN zhe-li DING Xiao-e YANG Ye-fei JIN Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China College of life Sciences Shaoxing College o fArts and SciencesShaoxing 312000China

The selection and breeding of pollution-safe cultivars (PSCs) is a practicable and cost-effective approach to minimize the influx of heavy metal to the human food *** this study,both pot-culture and field experiments were conducted to identify and screen out cadmium pollution-safe cultivars (Cd-PSCs) from 50 pakchoi (Brassica rapa ***) cultivars for food *** treated with 1.0 or 2.5 mg/kg Cd,most of the pakchoi cultivars (>70%) showed greater or similar shoot biomass when compared with the *** result indicates that pakchoi has a considerable tolerance to soil Cd *** concentrations in the shoot varied significantly (P<0.05) between cultivars:in two Cd treatments (1.0 and 2.5 mg/kg),the average values were 0.074 and 0.175 mg/kg fresh weight (FW),*** concentrations in the shoots of 14 pakchoi cultivars were lower than 0.05 mg/kg *** pot-culture experiments,both enrichment factors (EFs) and translocation factors (TFs) of six pakchoi cultivars were lower than *** field studies further confirmed that the Hangzhouyoudonger,Aijiaoheiye 333,and Zaoshenghuajing cultivars are Cd-PSCs,and are therefore suitable for growth in low Cd-contaminated soils (≤1.2 mg/kg) without any risk to food safety.

关键词： Cadmium pollution Food safety Pakchoi Pollution-safe cultivars

Effects of water and nitrogen conditions under surge-root irrigation on growth and yield of apple trees

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排灌机械工程学报 2023年第2期41卷 179-186页

作者： YIN Yongle FEI liangjun li zhe liU Teng li Zhongjie HAO Kun PENG Youliang Institute of Water Resources and Hydroelectric Engineering Xi′an University of TechnologyXi′anShaanxi 710048China Shaanxi Provincial Land Engineering Construction Group Land Survey Planning and Design InstituteXi′anShaanxi 710064China Rural Revitalization Planning and Development Guidance Center of Yulin YulinShaanxi 719000China

In order to explore the effects of different irrigation and nitrogen application on growth cha-racteristics and yield of apple trees under surge-root irrigation in mountainous areas of northern Shaanxi, field experiments were carried out with different apple trees. Three irrigation levels were applied: 85%-100%(H1), 70%-85%(H2) and 55%-70%(H3) of the field water capacity, respectively, and three nitrogen levels were N1(360 g/plant), N2(240 g/plant) and N3(120 g/plant). The results show that irrigation and nitrogen application has significant effects on new shoot length, flowering and fruit setting, fruit diameter, fruit volume and yield of apple. The leaf area index(LAI) shows a single trend during the growth period, and the peak value appears in the middle of July. Under the same irrigation level, compared with N3, N1 increases in yield, new shoot length, LAI, transverse diameter, longitudinal diameter, volume, flowering and fruit setting by 17.91%, 28.31%, 18.75%, 11.38%, 10.13%, 36.60%, 20.92% and 5.19%, respectively, while N2 also increases by 12.40%, 15.63%, 4.86%, 5.40%, 5.11%, 17.01%, 26.17% and 13.74%, respectively. The rate of flowering and fruit setting decreases with the increase of nitrogen application. Under the same nitrogen level, compared with H3, H1 increases in yield, new shoot length, LAI, transverse diameter, longitudinal diameter, volume, flowering and fruit setting by 34.65%, 15.49%, 30.77%, 3.93%, 4.95%, 12.86%, 33.15% and 28.62%, respectively, while H2 also increases by 33.67%, 16.42%, 67.52%, 3.81%, 2.97%, 11.57%, 43.45% and 27.26%, respectively. The rate of flowering and fruit setting decreases first and then increases with the increase of irrigation amount. Compared with H3N3, the yield of other treatments increases by 2.69%-52.20%, while H2N1 treatment has the highest yield(26 852.55 kg/ha). Considering from the point of view of promoting growth and increasing yield, the best water and nitrogen combination mode of mountain apple in northe

关键词： mountain apple surge-root irrigation irrigation nitrogen growth yield

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