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Using ^(137)Cs Tracing Methods to Estimate Soil Redistribution Rates and to Construct a Sediment Budget for a Small Agricultural Catchment in the Three Gorges Reservoir Region,China

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Journal of Mountain Science 2013年第3期10卷 428-436页

作者： JU Li WEN An-bang LONG Yi YAN dong-chun GUO Jin Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences University of Chinese Academy of Sciences

Soil erosion and associated off-site sedimentation are threatening the sustainable use of the Three Gorges Dam. To initiate management intervention to reduce sediment yields, there is an increasing need for reliable information on soil erosion in the Three Gorges Reservoir Region （TGRR）. The purpose of this study is to use 137Cs tracing methods to construct a sediment budget for a small agricultural catchment in the TGRR. Cores were taken from a pond and from paddy fields, for laTCs measurements. The results show that the average sedimentation rate in the pond since 1963 is 1.50 g cm-2 yr-1 and the corresponding amount of sediment deposited is 1,553 t. The surface erosion rate for the sloping cultivated lands and the sedimentation rate in the paddy fields were estimated to be 3,770 t km-2 yr-1 and 2,600 t km-2 yr^1 respectively. Based on the estimated erosion and deposition rates, and the area of each unit, the post 197o sediment budget for the catchment has been constructed. A sediment delivery ratio of 0.5 has been estimated for the past 42 years. The data indicate that the sloping cultivated lands are the primary sediment source areas, and that the paddy fields are deposition zones. The typical land use pattern （with the upper parts characterized by sloping cultivated land and the lower parts by paddy fields） plays an important role in reducing sediment yield from agricultural catchments in the TGRR. A 137Cs profile for the sediment deposited in a pond is shownto provide an effective means of estimating the land surface erosion rate in the upstream catchment.

关键词： Pond deposition Soil erosion rate Sediment budget 137Cs Sediment delivery ratio Three Gorges Reservoir Region

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Genitourinary function and defecation after colorectal cancer surgery with low-and high-ligation of the inferior mesenteric artery:A meta-analysis

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World Journal of Gastrointestinal Surgery 2021年第8期13卷 871-884页

作者： Xiao Bai chun-dong Zhang Jun-Peng Pei dong-Qiu Dai Department of Gastrointestinal Surgery the Fourth Affiliated Hospital of China Medical UniversityShenyang 110032Liaoning ProvinceChina Department of Gastrointestinal Surgery Graduate School of MedicineThe University of TokyoTokyo 113-0033Japan Cancer Center the Fourth Affiliated Hospital of China Medical UniversityShenyang 110032Liaoning ProvinceChina

BACKGROUND The effect of low ligation(LL)vs high ligation(HL)of the inferior mesenteric artery(IMA)on functional outcomes during sigmoid colon and rectal cancer surgery,including urinary,sexual,and bowel function,is still *** To assess the effect of LL of the IMA on genitourinary function and defecation after colorectal cancer(CRC)*** EMBASE,PubMed,Web of Science,and the Cochrane Library were systematically searched to retrieve studies describing sigmoid colon and rectal cancer surgery in order to compare outcomes following LL and HL.A total of 14 articles,including 4750 patients,were analyzed using Review Manager 5.3 *** results are expressed as odds ratios(ORs)with 95%confidence intervals(CIs)and continuous outcomes are expressed as weighted mean differences(WMDs)with 95%*** LL resulted in a significantly lower incidence of nocturnal bowel movement(OR=0.73,95%CI:0.55 to 0.97,P=0.03)and anastomotic stenosis(OR=0.31,95%CI:0.16 to 0.62,P=0.0009)compared with *** risk of postoperative urinary dysfunction,however,did not differ significantly between the two *** meta-analysis also showed no significant differences between LL and HL in terms of anastomotic leakage,postoperative complications,total lymph nodes harvested,blood loss,operation time,tumor recurrence,mortality,5-year overall survival rate,or 5-year disease-free survival *** Since LL may result in better bowel function and a reduced rate of anastomotic stenosis following CRC surgeries,we suggest that LL be preferred over HL.

关键词： Low ligation High ligation Colorectal cancer Genitourinary function Defecatory function Meta-analysis

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Inorganic nitrogen removal of toilet wastewater with an airlift external circulation membrane bioreactor

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Journal of Environmental Sciences 2007年第1期19卷 12-17页

作者： LI Gang WU Lin-lin dong chun-song WU Guang-xia FAN Yao-bo Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Removal of inorganic nitrogen （inorganic-N） from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor （AEC-MBR） was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19-0.40 kg inorganic-N/（m^3·d） helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen （DO） on inorganic-N removal were examined. Under the condition of MLSS at 1.56-2.35 g/L, BODs/ammonia nitrogen （NH4＋-N） at 1.0, pH at 7.0-7.5, and DO at 1.0-2.0 mg/L, the removal efficiencies of NH4^＋-N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5-1.5 RMB yuan/m^3, and the energy consumption was approximately 0.72 kWh/m^3 at the flux of 8 L/（m^2-h）.

关键词： inorganic nitrogen removal treatment of wastewater from toilet airlift external circulation membrane bioreaetor (AECMBR) membrane bioreactor (MBR)

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Palatability of Water-Soluble Extracts of Protein Sources and Replacement of Fishmeal by a Selected Mixture of Protein Sources for Juvenile Turbot(Scophthalmus maximus)

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Journal of Ocean University of China 2016年第3期15卷 561-567页

作者： dong chun HE Gen MAI Kangsen ZHOU Huihui XU Wei Key Laboratory of Water Project Ecological Effect and Ecological Restoration Institute of HydroecologyMinistry of Water Resources and Chinese Academy of Sciences Key Laboratory of Aquaculture Feed and Nutrition of Ministry of Agriculture Ocean University of China

Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. The present study was conducted to investigate the palatability of water-soluble extracts from single protein source(single extract pellets) and the mixture of these extracts with different proportions(blended extract pellets) in juvenile turbot(Scophthalmus maximus). Then according to the palatability of blended extract pellets, an optimal mixture proportion was selected, and a new protein source made from raw protein materials with the selected proportion was formulated to replace fishmeal. Summarily, the palatability of single extract pellets for turbot was descendent from fishmeal to pet-food grade poultry by-product meal, wheat gluten meal, soybean meal, peanut meal, meat and bone meal, and corn gluten meal. Subsequently, according to the palatability of single extract pellets, 52 kinds of blended extract pellets were designed to test their palatability. The results showed that the pellets presented remarkably different palatability, and the optimal one was diet 52(wheat gluten meal: pet-food grade poultry by-product meal: meat and bone meal: corn gluten meal = 1:6:1:2). The highest ingestion ratio(the number of pellets ingested/the number of pellets fed) was 0.73 ± 0.03, which was observed in Diet 52. Then five isonitrogenous(52% crude protein) and isocaloric(20 k J g^(-1) gross energy) diets were formulated by replacing 0(control), 35%, 50%, 65% and 80% of fishmeal with No.52 blending proportion. After a 10-weeks feeding trial, a consistent feed intake was found among all replacement treatments. Replacement level of fishmeal up to 35% did not significantly influence final body weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio of turbot. Therefore, the water-soluble extracts of protein sources play an important role

关键词： protein source water-soluble extract palatability fishmeal replacement turbot

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Spin-Polarization of Ferroelectric Supperlattice with Spin-1/2 Transverse Ising Model

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Communications in Theoretical Physics 2011年第6期55卷 1024-1028页

作者： WANG chun-dong TENG Bao-Hua LU Zhen-Zhen KWOK So-Ying Center of Super-Diamond and Advanced Films （COSDAF） and Department of Physics and Materials Science City University of Hong Kong Hong Kong China School of Physical Electronics University of Electronic Science and Technology of China Chengdu 610054 China

By using the simple decoupling approximation to Fermi-type Green＇s function for the transverse Ising model under pseudospin theory, we systemically study the influence of different exchange interactions （transverse fields） of the two distinct materials on the polarization and Curie temperature of finite alternating superlattice. Meanwhile, we analyze the effect of the whole parameters of the top surface, present their influence on the polarization of each layer （including the mean polarization of the whole ferroeleetric superlattiee） and on the Curie temperature. The results show the ratio of the exchange interactions （the transverse fields）, which are of the two alternating materials have deeply impact on the polarization and Curie temperature of the supperlattice. Moreover, the top surface also has great influence on the whole ferroelectric superlattice.

关键词： ferroelectric superlattice spin-polarization

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Spatial distribution,sources and ecological risk assessment of heavy metals in Shenjia River watershed of the Three Gorges Reservoir Area

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Journal of Mountain Science 2017年第2期14卷 325-335页

作者： WANG Yong-yan WEN An-bang GUO Jin SHI Zhong-lin YAN dong-chun Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Chinese Academy of Sciences University Beijing 100049China Sichuan Electric Power Design Institute Chengdu 610072China

Surface soil/sediment samples were collected from the Water-Level Fluctuation Zone(WLFZ), cultivated land and forest land at 50 different grid points from Shenjia watershed, the Three Gorges Reservoir area in August 2013. The spatial distribution, sources and ecological risk assessment for Arsenic(As), Cadmium(Cd),Chromium(Cr), Copper(Cu), Nickel(Ni), Lead(Pb)and Zinc(Zn) were analyzed in this study. The results showed all tested metals had similar distribution patterns except Ni and Cr, with areas of high concentrations distributed in the southwest(WLFZ and watershed outlet) of the study area. Ni and Cr,which were highly positively correlated and present in high concentrations, were primarily distributed in the south and middle zones of the study area. Lower concentration areas of all metals were uniformly distributed west of the high-elevation zones and forest land. Factor analysis(FA) and factor analysismultiple linear regression(FA-MLR) showed that the major sources of Cd were fertilizer and traffic sources,which together accounted for 87% of Cd. As, Zn and Cu levels were primarily supplied by industrial and domestic sources, accounting for 76% of As, 75% of Cu and 67% of Zn. Surface soils/sediments of the study watershed contaminated by Cd represent a high ecological risk, whereas other metals represent low ecological risks. The potential ecological risk index(PERI) analysis indicated that it had a low(widerange) ecological risk and a moderate(small-range)ecological risk primarily distributed in the outlet of the study watershed. Fertilizers and traffic are the primary sources of Cd pollution, which should be more closely controlled for the purposes of water quality and ecological conservation.

关键词： Spatial distribution Ecological risk assessment Water-level fluctuation zone Heavy metals Three Gorges Reservoir

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Detection of Thrips Defect on Green-Peel Citrus Using Hyperspectral Imaging Technology Combining PCA and B-Spline Lighting Correction Method

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Journal of Integrative Agriculture 2014年第10期13卷 2229-2235页

作者： dong chun-wang YE Yang ZHANG Jian-qiang ZHU Hong-kai LIU Fei Tea Research Institute Chinese Academy of Agricultural Sciences School of Food and Biological Engineering Jiangsu University

In order to find an effective method of detecting thrips defect on green-peel citrus, a defect segmentation method was developed using a single threshold value based on combination of characteristic wavelengths principal component analysis （PCA） and B-spline lighting correction method in this study. At first, four characteristic wavelengths （523, 587, 700 and 768 nm） were obtained using PCA of Vis-NIR （visible and near-infrared） bands and analysis of weighting coefficients; secondarily, PCA was performed using characteristic wavelengths and the second principal component （PC2） was selected to classify images; then, B-spline lighting correction method was proposed to overcome the influence of lighting non-uniform on citrus when thrips defect was segmented; finally, thrips defect on citrus was extracted by global threshold segmentation and morphological image processing. The experimental results show that thrips defect in citrus can be detected with an accuracy of 96.5% by characteristic wavelengths PCA and B-spline lighting correction method. This study shows that thrips defect on green-peel citrus can be effectively identified using hyperspectral imaging technology.

关键词： hyperspectral images principal component analysis lighting correction green-peel citrus thrips defect

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Reactive Plasma Sprayed TiN Coating and Its Thermal Stability

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Journal of Iron and Steel Research International 2007年第5期14卷 71-75页

作者： ZOU dong-li YAN Dian-ran HE Ji-ning LI Xiang-zhi dong Yan-chun ZHANG Jian-xin School of Materials Hebei University of Technology Tianjin 300132 China School of Materials Science andEngineering Harbin Institute of Technology Harbin 150001 Heilongjiang China

TiN coating was prepared by reactive plasma spraying in the Ar and N2 containing plasma jet. The resuits of XRD show that the TiN coating consists of TiN and Ti3 O, neither Ti2 N nor TiO2 phases. The toughening mechanism was characterized by analyzing the SEM morphologies of the TiN coating＇s indentation of microhardness and fracture surfaces. The results indicate that the coating possesses a high toughness. The adhesion strength among the TiN layers is 25.88 MPa, which is slightly lower than that of the Ni/AI bonding coating. The oxidation process of the RPS TiN coating is TiN→Ti3 O→TiO2.

关键词： plasma spraying reactive plasma spraying TiN coating

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π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao dong-chun Zheng Pin-Xi Ou Qi-Xin Zhao Wei-Min Xuan Qi Zheng State Key Laboratory for Modification of Chemical Fibers and Polymer Materials&College of Materials Science and Engineering Donghua UniversityShanghai201620China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials and College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China

N-doping has significant influence in manipulating the properties of TiO_(2),and this has stimulated the development of N-donor-functionalized titanium-oxo clusters(TOCs)as molecular models to study the structure-property ***,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO_(2)for ***,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds usingπ-conjugated 1,10-phenanthroline(phen)as chromophore and N-donor functional *** 1 features cocrystal structure composed of one[Ti_(26)]~(2+)and half[Ti_(22)]~(2+),which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti *** adjusting the synthetic conditions,the individual{Ti_(22)}and{Ti_(26)}clusters can also be isolated as Compounds 2 and 3,*** core structure of{Ti_(22)}is mainly constructed from four lacunary{Ti_(4)}derived from pentagonal{Ti(Ti)_5}unit,while{Ti_(26)}is built from four complete{Ti(Ti)_5}***,a{Ti_8O_(14)}structure unit of anatase TiO_(2)can be identified in{Ti_(26)}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic *** to the presence of anatase structure unit in{Ti_(26)}and the synergistic effect from{Ti_(22)}and{Ti_(26)},the catalytic performance presents in the order of Compound 1>Compound 3>Compound *** work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO_(2) High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

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Nearfield acoustic holography in a moving medium based on particle velocity input using nonsingular propagator

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Chinese Physics B 2022年第2期31卷 414-422页

作者： Bi-chun dong Run-Mei Zhang Bin Yuan Chuan-Yang Yu Department of Mechanical&Electrical Engineering School Anhui Jianzhu UniversityHefei 230601China

Nearfield acoustic holography in a moving medium is a technique which is typically suitable for sound sources identification in a *** the process of sound field reconstruction,sound pressure is usually used as the input,but it may contain considerable background noise due to the interactions between microphones and flow moving at a high *** avoid this problem,particle velocity is an alternative input,which can be obtained by using laser Doppler velocimetry in a non-intrusive ***,there is a singular problem in the conventional propagator relating the particle velocity to the pressure,and it could lead to significant errors or even false *** view of this,in this paper,nonsingular propagators are deduced to realize accurate reconstruction in both cases that the hologram is parallel to and perpendicular to the flow *** advantages of the proposed method are analyzed,and simulations are conducted to verify the *** results show that the method can overcome the singular problem effectively,and the reconstruction errors are at a low level for different flow velocities,frequencies,and signal-to-noise ratios.

关键词： nearfield acoustic holography moving medium particle velocity nonsingular propagator

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