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Influence of the roots of mixed-planting species on the shear strength of saline loess soil

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Journal of Mountain Science 2021年第3期18卷 806-818页

作者： LIU Ya-bin HU Xia-song yu dong-mei ZHU Hai-li LI Guo-rong Department of Geological Engineering Qinghai UniversityXining 810016China Qinghai Institute of Salt Lakes Chinese Academy of ScienceXining 810008China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Geology and Environment of Salt LakesXining 810008China

In order to improve our knowledge of the mechanical effect of the roots of mixed-plantings on soil reinforcement and slope protection,the influence of roots of a mixed-planting with four herb species(Medicago sativa L.,Elymus nutans Griseb.,Puccinellia distanx(L.),and Poa pratensis L.)and one shrub species(Caragana korshinskii Kom.)were investigated on the shear strength characteristics of saline loess *** root distribution characteristics were assessed via a survey when the plants grew for one *** effects of the root biomass density,the root mass ratio(RMR)of the fine roots to the coarse roots,the moisture content,and the salt content on the shear strength index of the rooted soil were analyzed via a triaxial compression test,and the mechanism of these effects was *** results indicate that the biomass density decreased linearly with increasing *** RMR initially decreased with depth and then increased,exhibiting in a quadratic *** cohesion of the rooted soil increased linearly as the biomass density *** cohesion of the rooted soil initially increased with increasing RMR and salt content,and then it *** turning point of the cohesion occurred when the RMR was 0.6 and the salt content was 1.18%.The internal friction angle of the rooted soil initially increased with biomass density and then decreased,and the turning point of the internal friction angle occurred when the biomass density was 0.015 g/*** relationships between the internal friction angle of the rooted soil and the RMR and salt content were exponential incremental and linear subtractive relationship,*** the cohesion and the internal friction angle of the rooted soil linearly decreased with increasing moisture content.

关键词： Xining Basin Herb species Shrub species Rooted soil Saline loess soil Soil reinforcement Shear strength index

Recent research progress in geochemical properties and restoration of heavy metals in contaminated soil by phytoremediation

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Journal of Mountain Science 2019年第9期16卷 2079-2095页

作者： FU Jiang-tao yu dong-mei CHEN Xi SU Ying LI Cai-hong WEI Yong-ping School of Civil Engineering and Architecture Shaanxi University of Technology Hanzhong 723001 China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China School of biological sciences and engineering Shaanxi University of Technology Hanzhong 723001 China Shaanxi University of Technology Hanzhong 723001 China

Heavy metals are widely distributed contaminants in natural environments and their potential threats to human health have attracted worldwide concerns due to the food chain. Therefore, great efforts have been made to reduce them to a safe level in soil. Compared with the traditional methods, the method using plants to remove them has been accepted as a feasible and efficient way. Herein, the geochemical behavior of heavy metals and the restoration methods with phytoremediation were reviewed. In addition, issues on heavy metal speciation as well as its influencing factors, phytoremediation mechanism, phytoremediation effect and vegetation selection principle used for phytoremediation were discussed.

关键词： Heavy metals Geochemical properties Phytoremediation Hyperaccumulator

Changes in Waist Circumference and Abdominal Obesity among Chinese Adults over a Ten-year Period

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Biomedical and Environmental Sciences 2017年第5期30卷 315-322页

作者： ZHAI Yi FANG Hong yun yu Wen Tao yu dong mei ZHAO Li yun LIANG Xiao Feng ZHAO Wen Hua Chinese Center for Disease Control and Prevention Beijing 102206 China National Institute for Nutritionand Health Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective The aim of this study was to describe changes in waist circumference（WC） and prevalence of abdominal obesity over a period of 10 years among Chinese adults in different socio-economic status（SES）. Methods Data derived from the China Nutrition and Health Surveillance during 2002 and 2010-2012. We calculated the mean WC and the prevalence of abdominal obesity by gender, place of residence, SES indicators（education, income, and marital status）, and body mass index（BMI） categoriesand used pooled t-tests to assess the differences between the two time periods. Results 26.0% of men and 25.3% of women had abdominal obesity in 2010-2012. The age-adjusted mean WC increased by 2.7 cm among men and 2.1 cm among women; the age-adjusted prevalence of abdominal obesity increased by 7.7% among men and 5.3% among women. The rising trends were observed in all subgroups except for a negative growth in high-income women. People living in rural areas with low education and income and with a BMI of 18.5 to 23.9 kg/m^2 had a greater absolute and relative increase in WC. People living in rural areas with low income had a greater relative increase in abdominal obesity. Conclusion The mean WC and prevalence of abdominal obesity among Chinese adults have increased during the past 10 years. Gender differences were noted using various SES indicators.

关键词： Waist circumference Abdominal obesity Socio-economic indicators Trends China

Challenges Brought about by Rapid Changes in Chinese Diets: Comparison with Developed Countries and Implications for Further Improvement

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Biomedical and Environmental Sciences 2018年第10期31卷 781-786页

作者： ZHAO Li yun LIU Dan yu dong mei ZHANG Jian WANG Jing Zhong ZHAO Wen Hua National Institute for Nutrition and Health Chinese Center for Disease Control and Prevention

Given developments in urbanization, agricultural, and technological practices, the diet and lifestyle of developed countries has changed dramatically over the course of the last century[1].

关键词： Challenges Brought about by Rapid Changes in Chinese Diets Comparison with Developed Countries and Implications for Further Improvement

Variable hydrological effects of herbs and shrubs in the arid northeastern Qinghai-Tibet Plateau,China

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Journal of Mountain Science 2018年第7期15卷 1532-1545页

作者： LIU Ya-bin ZHANG Ying FU Jiang-tao yu dong-mei HU Xia-song LI Xi-lai QI Zhao-xin LI Shu-xia Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of SaltLakes Chinese Academy of Sciences Xining 810008 China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Xining 810008 China University of Chinese Academy of Sciences Beijing 100049 China Department of Geological Engineering Qinghai University Xining 810016 China College of Agriculture and Animal Husbandry Qinghai University Xining 810016 China

This study aims to assess the hydrological effects of four herbs and four shrubs planted in a selfestablished test area in Xining Basin of northeastern Qinghai-Tibet Plateau, China. The RainfallIntercepting Capability(RIC) of the herbs and shrubs was evaluated in rainfall interception experiment at the end of the third, fourth and fifth month of the growth period in 2007. The leaf transpiration rate and the effects of roots on promoting soil moisture evaporation in these plants were also assessed in transpiration experiment and root-soil composite system evaporation experiment in the five month's growth period. It is found that the RIC of the fourstudied herbs follows the order of E. repens, E. dahuricus, A. trachycaulum and L. secalinus; the RIC of the four shrubs follows the order of A. canescens, Z. xanthoxylon, C. korshinskii and N. tangutorum. The RIC of all the herbs is related linearly to their mean height and canopy area(R^2 ≥ 0.9160). The RIC of all the shrubs bears a logarithmic relationship with their mean height(R^2 ≥ 0.9164), but a linear one with their canopy area(R^2 ≥ 0.9356). Moreover, different species show different transpiration rates. Of the four herbs, E. repens has the highest transpiration rate of 1.07 mg/(m^2·s), and of the four shrubs, A. canescens has the highest transpiration rate(0.74 mg/(m^2·s)). The roots of all the herbs and shrubs can promote soil moisture evaporation. Of the four herbs, the evaporation rate of E. repens root-soil composite system is the highest(2.14%), and of the four shrubs,the root-soil composite system of A. canescens has the highest evaporation rate(1.41%). The evaporation rate of the root-soil composite system of E. dahuricus and Z. xanthoxylon bears a second-power linear relationship with evaporation time(R^2 ≥ 0.9924). The moisture content of all the eight root-soil composite systems decreases exponentially with evaporation time(R^2 ≥ 0.8434). The evaporation rate and moisture content of all the plants' root-

关键词： Plant hydrological effects Rainfall interception capacity Root-soft composite system Transpiration rate Moisture evaporation rate Qinghai-Tibet Plateau

Influences of soil moisture and salt content on loess shear strength in the Xining Basin, northeastern Qinghai-Tibet Plateau

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Journal of Mountain Science 2019年第5期16卷 1184-1197页

作者： FU Jiang-tao HU Xia-song LI Xi-lai yu dong-mei LIU Ya-bin YANG You-Qing QI Zhao-xin LI Shu-xia Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes University of Chinese Academy of Sciences Department of Geological Engineering Qinghai University College of Agriculture and Animal Husbandry Qinghai University

Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides collapse and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through salt-leaching in the laboratory. The desalinized and oven-dried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways(moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events.

关键词： Salinized loess Desalinized loess Salt-leaching Shear strength indices Moisture content Salt content

Comparison of Undernutrition Prevalence of Children under 5 Years in China between 2002 and 2013

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Biomedical and Environmental Sciences 2016年第3期29卷 165-176页

作者： yu dong mei ZHAO Li yun YANG Zhen yu CHANG Su Ying yu Wen Tao FANG Hong yun WANG Xun yu Dan GUO Qi Ya XU Xiao Li FANG yue Hui ZHAO Wen Hua YANG Xiao Guang DING Gang Qiang LIANG Xiao Feng National Center for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China United Nations Children's Fund Beijing 100600China Chinese Center for Disease Control and Prevention Beijing 102206China

Objective To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013. Methods The study was based on two national surveys. Undernutrition was determined against WHO＇s 2006 growth standards. The prevalence in 2013 and 2002 was weighted by China sixth National Population Census （2010）. The relationship between undernutrition and gender/age groups/different areas use weighted logistic regression. Results The results indicated the overall prevalence of stunting, underweight, and wasting of Chinese children under S-year was 8.1%, 2.4%, and 1.9% in 2013, respectively. The prevalence of stunting was higher for children aged 12-47 month, while underweight was higher for children aged 48-59 month. The prevalence of undernutrition was higher in rural areas than in urban areas, especially in poor rural areas. There was a decline of stunting, underweight, and wasting between 2002 and 2013 among the children, with greater reduction in rural areas than in urban areas. Conclusion The prevalence of undernutrition of children under 5-year remains high in rural areas especially in poor rural areas in China. It is urgent to take action to control undernutrition in the vulnerable areas and subgroups.

关键词： Undernutrition Prevelence Children under 5

Proteomic response analysis of endothelial cells of human coronary artery to stimulation with carbachol

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Acta Pharmacologica Sinica 2004年第9期 22-28页

作者： Min yu, dong-mei CHEN, Gang HU, Hai WANGBeijing Institute of Pharmacology and Toxicology, Beijing 100850, China Department of Pharmacology and Neurobiology, Nanjing Medical University, Nanjing 210029,China

AIM: To identify the molecular basis of the endothelial target for acetylcholine (ETA). METHODS: Proteomic methods were used to monitor changes in protein expression in the first 10 h following the stimulation of human coronary endothelial cells with carbachol 100 μmol/L. Thirty proteins showing the largest changes were identified by mass spectrometry. RESULTS: Based on analysis with Image Master 2-D

关键词： endothelium carbachol human coronary artery endothelial cells proteome two-dimensional gel electrophoresis protein identification

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang Wei-Wei Wang mei-Qian Fu Hong-Bing Mo Wei-dong yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium