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Carbon Sequestration Effects of Shrublands in Three-North Shelterbelt Forest Region, China

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Chinese Geographical Science 2014年第4期24卷 444-453页

作者： LIU Wenhui ZHU Jiaojun JIA Quanquan ZHENG xiao LI Junsheng lou Xuedong HU Lile State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Institute of Applied Ecology Chinese Academy of Sciences Key Laboratory of Forest Cultivation Department of Forest Sciences Beijing Forestry University

Three-North Shelterbelt Forest （TSF） program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that： 1） The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10^7 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2） In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo vat. heterophylla. The carbon sequestration of/-/, rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3） The total carbon sequestration of shrubland in the study region was 4.5 x 107 Mg C with a mean annual carbon sequestration of 1.5× 10^6 Mg C. The carbon density in the four sub-regions decreased in the following order： the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a base

关键词： biomass biomass density carbon density carbon sequestration carbon sequestration rate carbon storage Three-NorthShelterbelt Forest (TSF)

A novel approach based on a modified mask R-CNN for the weight prediction of live pigs

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Artificial Intelligence in Agriculture 2024年第2期12卷 19-28页

作者： Chuanqi Xie Yuji Cang Xizhong lou Hua xiao Xing Xu Xiangjun Li Weidong Zhou State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products Institute of Animal Husbandry and Veterinary ScienceZhejiang Academy of Agricultural SciencesHangzhou 310021China College of Information Engineering China Jiliang UniversityHangzhou 310018China College of Hydraulic Engineering Zhejiang Tongji Vocational College of Science and TechnologyHangzhou 311231China

Since determining the weight of pigs during large-scale breeding and production is challenging,using non-contact estimation methods is *** study proposed a novel pig weight prediction method based on a mod-ified mask region-convolutional neural network(mask R-CNN).The modified approach used ResNeSt as the backbone feature extraction network to enhance the image feature extraction *** feature pyramid net-work(FPN)was added to the backbone feature extraction network for multi-scale feature *** channel at-tention mechanism(CAM)and spatial attention mechanism(SAM)were introduced in the region proposal network(RPN)for the adaptive integration of local features and their global dependencies to capture global in-formation,ultimately improving image segmentation *** modified network obtained a precision rate(P),recall rate(R),and mean average precision(MAP)of 90.33%,89.85%,and 95.21%,respectively,effectively segmenting the pig regions in the *** image features,namely the back area,body length,body width,average depth,and eccentricity,were *** pig depth images were used to build five regression algo-rithms(ordinary least squares(OLS),AdaBoost,CatBoost,XGBoost,and random forest(RF))for weight value *** achieved the best prediction result with a coefficient of determination(R^(2))of 0.987,a mean absolute error(MAE)of 2.96 kg,a mean square error(MSE)of 12.87 kg^(2),and a mean absolute percentage error(MAPE)of 8.45%.The results demonstrated that the machine learning models effectively predicted the weight values of the pigs,providing technical support for intelligent pig farm management.

关键词： Deep learning Modified mask R-CNN Image processing Pig weight Prediction

Syntheses and Anti-cancer Activities of Glycosylated Derivatives of Diosgenin

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Chemical Research in Chinese Universities 2017年第1期33卷 80-86页

作者： TAN Yonghua xiao xiao YAO Jianing HAN Fei lou Huayong LUO Heng LIANG Guangyi BEN-DAVID Yaacov PAN Weidong Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang 550002 P R. China Key Laboratory of Chemistry for Natural Products of Guizhou Medical University Guiyang 550001 P. R. China

In order to obtain better anti-cancer compounds, nine glycosylated derivatives were designed and synthe- sized using diosgenin as starting material. Their structures were confn-med by 1H NMR, 13C NMR and MS spectra. The anti-cancer activities of intermediate compounds 5a-5i and the target compounds 6a-6i were investigated against human leukemia HEL, K562, HL60 and melanoma WM9 cell lines via MTT method. The bioassay results show that these derivatives possess good inhibitory activities against the four cancer cell lines. Furthermore, these derivatives show better inhibitory activities against K562 than against other cell lines, and most derivatives show better inhibitory activities than the parental material. Moreover, compounds 6a--6i are more active than their inter- mediates 5a--5i when against these ceils. The above results demonstrate the effects of glycosylation on 3-OH of di- osgenin and acetylation of the sugar moiety on their antitumor activities.

关键词： Diosgenin Glycosylation Anti-cancer activity

T2 relaxation time measurements in the brains of scalded rats

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Science China(Life Sciences) 2017年第1期60卷 5-10页

作者： Tao Jiang Liqi Xie Xin lou Dawei Li Zhiye Chen Huafeng xiao Lin Ma Department of Radiology PLA General Hospital Department of Radiology PLA 401 Hospital Department of Burn and Plastic Surgery PLA 304 Hospital Department of Radiology PLA 302 Hospital

This study aimed to evaluate the T2 relaxation time of the brain in severely scalded rats using a magnetic resonance （MR） T2 mapping sequence, and to investigate the correlation between T2 relaxation time and plasma glucose level. Twenty-eight Wistar rats were randomly divided into the scalded group （n = 21）and control group （n = 7）. Magnetic resonance scans were performed with T1WI, T2WI, and T2-mapping sequences in the scalded group; the scans were performed 1 day prior to scalding and 1, 3, 5, and 7 days post-scalding; in addition, identical MR scans were performed in the control group at the same time points. T2-maps were generated and T2 relaxation times were acquired from the following brain regions： the hippocampus, thalamus, caudate-putamen, and cerebrum. Pathological changes of the hippocampus were observed. The plasma glucose level of each rat was measured before each MR scan, and a correlation analysis was performed between T2 relaxation time and plasma glucose level. We found that conventional T 1WI and T2WI did not reveal any abnormal signals or morphological changes in the hippocampus, thalamus, caudate-putamen,： or cerebrum post-scalding. Both the T2 relaxation times of the selected brain regions and plasma glucose levels increased 1, 3, and 5 days post-scalding, and returned to normal levels 7 days post-scalding. The most marked increase of T2 relaxation time was found in the hippocampus; similar changes were also revealed in the thalamus, caudate-putamen, and cerebrum. No correlation was found between T2 relaxation time and plasma glucose level in scalded rats. Pathological observation of the hippocampus showed edema 1, 3, and 5 days post-scalding, with recovery to normal findings at 7 days post-scalding. Thus, we concluded that T2 mapping is a sensitive method for detecting and monitoring scald injury in the rat brain. As the hippocampus is the main region for modulating a stress reaction, it showed significantly increased water content along with

关键词： burns magnetic resonance imaging T2 relaxation time hippocampus

Preparation of Mo_2C nanoparticles dispersion-strengthened copper-based composite by EB-PVD

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Rare Metals 2014年第5期33卷 568-572页

作者： xiao Li Guang-Ping Song Fan-Yu Bu Bin Xu Bai-Yang lou Zhan Lin College of Materials Science and Engineering Zhejiang University of Technology Center for Composite Materials and Structures Harbin Institute of Technology

In this research, a nano-Mo2 C particle dispersion-strengthened copper alloy was prepared by a novel method, i.e., electron beam physical vapor deposition（EBPVD） which has advantages of simple technical process and low cost compared with the conventional mechanical alloying method. And the microstructure and properties of the material were investigated. The results show that the copper matrix is composed of columnar crystals with the average width of 7 lm, and the size of Mo2 C dispersoid is1–7 nm. The ultimate tensile strength of the material is486 MPa, and the electrical conductivity is 82 % IACS. As the temperature increases from 293 to 573 K, the material becomes more brittle.

关键词： Electron beam physical vapor deposition Dispersion-strengthened copper ODS In-situ

Implementing an“Impracticable”Copolymerization to Fabricate a Desired Polymer Precursor for N-doped Porous Carbons

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Engineering 2022年第9期16卷 154-161页

作者： Shi-Chao Qi xiao-Jie Lu Yin-Cong lou Rui Zhou Ding-Ming Xue xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Material(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

It is common that a proof-of-concept of a desired reaction,which might generate materials with new functions or application potential,is eventually proved impracticable or commercially *** efforts have been made but wasted in searching for unknown reaction conditions in solvent environments because it was believed that the activity of reactants can be enhanced to facilitate reactions by dissolving them in ***,an abnormal case was discovered in this study.A desired copolymerization reaction between 1,3,5-tris(chloromethyl)-2,4,6-trimethylbenzene and melamine was confirmed to be impracticable under various solvent conditions;however,it was successfully implemented using a solvent-free *** first-principle calculations and molecular dynamics simulations,two decisive factors that the reaction in solvents cannot possess,namely the reaction equilibrium being pushed by the timely release of by-products and the confined thermal motions of the activated monomer molecules in the solid phase,were demonstrated to make the copolymerization successful in the solvent-free *** to the high aromaticity and azacyclo-content,the as-synthetic copolymer exhibited good application potential as a precursor to fabricate N-doped porous carbons with satisfactory carbon yields,ideal N contents,desired textural properties,and competitive CO_(2)capture abilities compared to other representative counterparts reported recently.

关键词： Solvent-free method Solvent effect Copolymerization N-doped porous carbon

Study of moss as air pollution monitor by SRXRF technique

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Chinese Science Bulletin 2009年第17期54卷 2987-2990页

作者： ZHANG YuanXun CAO tong ATSUO lida CAO QingChen lou YuXia ZHANG GuiLin LI Yan Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Life and Environment Science College Shanghai Normal University Shanghai 200234 China Photon Factory National Laboratory for High Energy Physics Tsukuba Ibaraki 305 Japan

In order to explore the mechanism of moss as air pollution biomonitor, the moss samples were exposed in a pollution site of Shanghai Institute of Steel Research (SISR) and a control site of Shanghai Institute of Applied Physics (SIAP) simultaneously for one month. The concentrations of trace elements in the micro areas of leaf and stem, as well as in the whole moss tissue, were determined using synchrotron radiation X-ray fluorescence (SRXRF) method. The distributions of some metal elements such as Pb, Cu, Fe, Ni, Mn, Zn, Ca and K in the leaf surface and the stem slice were obtained. The results showed that the metallic ions were not evenly distributed after adsorption. In particular, some elements of K, Ni, Fe, Pb, etc., were concentrated in the leaf apex and the intermediate rib. Under pollution condition, the excessive Pb was adsorbed and deposited in the leaf. It caused serious damage to plant growth and ultrastructure, also suppressed moss’ normal absorption to the nutritive elements of K, Ca, etc.

关键词：空气污染同步辐射生物监测荧光技术金属离子吸附 X射线荧光法中国科学院 SRXRF

Game-theoretical Models of a Two-echelon Supply Chain Involving Two Substitutable Products

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 307-320页

作者： Zhenkai lou Fujun Hou Xuming lou Tingting Ma School of Management and Economics Beijing Institute of TechnologyBeijingChina School of Economics and Management Xi’an University of Posts and TelecommunicationsXi’anChina School of Logistics Beijing Wuzi UniversityBeijingChina

This paper considers tripartite pricing issues in a two-echelon supply chain involving duopolistic manufacturers and a single ***,a tripartite competitive model is conducted,in which both a Stackelberg game and a Bertrand game occur *** is shown that the manufacturer who possesses a higher sales quantity gains more profits than the other ***,a definition of optimal vertical pricing alliance is proposed when cooperation exists between the retailer and some *** conduct two-player games when partial cooperation exists among the three *** is demonstrated that the total profit of the alliance is higher than the sum profit of the corresponding two participants in the tripartite competition model,and meanwhile the profit of the manufacturer who is not in the alliance suffers a ***,a criterion is given to judge which manufacturer the retailer will choose to cooperate in order to maximize the total increased *** the perspective of game theory,we examine the stability of the vertical alliance with considering the dominance of the ***,a numerical illustration is designed to examine the judging criteria of which manufacturer is the member of the optimal alliance under different potential market demands.

关键词： Tripartite pricing game substitutable products equivalent judging criterion optimal vertical pricing alliance

A Multilane Traffic Flow Model with Lane Width and the Number of Lanes

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Chinese Physics Letters 2012年第9期29卷 240-243页

作者： TANG Tie-Qiao YANG xiao-Bao WU Yong-Hong CACCETTA lou HUANG Hai-Jun School of Transportation Science and Engineering Beihang UniversityBeijing 100191 Department of Mathematics and Statistics Curtin UniversityPerth WA 6845Australia School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044 School of Economics and Management Beihang UniversityBeijing 100191

Based on empirical data,we develop a macro model with lane width and the number of *** uniform flow,the model is formulated as a couple of algebra equations and solved by analytical *** results show that the proposed model can capture the impacts of lane width,the number of lanes and the variation of the number of lanes on uniform flow.

关键词： flow. uniform algebra