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1The state-of-the-art of the China Seismo-Electromagnetic Satellite mission显示文摘The China Seismo-Electromagnetic Satellite(CSES) mission was proposed in 2003 and approved in 2013 after ten years' scientific and engineering demonstrations. To meet the requirement of scientific objectives, the satellite is designed to be in a sunsynchronous orbit with an altitude of 507 km and descending node time of 14:00 LT. The CSES satellite carries 8 instruments,including search-coil magnetometer(SCM), electric field detector(EFD), high precision magnetometer(HPM), GNSS occultation receiver(GOR), plasma analyzer package(PAP), langmuir probe(LAP), high energetic particle package(HEPP) and detector(HEPD), and tri-band beacon(TBB), among which HEPD is provided by Italian Space Agency. The CSES satellite was launched successfully on February 2, 2018, and is planned to operate for 5 years. The CSES mission is the first satellite in China to measure geophysical fields, which will have a lot of application prospects in the study of seismology, geophysics, space sciences, and so on.SHEN XuHui ZHANG XueMin YUAN ShiGeng WANG LanWei CAO JinBin HUANG JianPing ZHU Xing Hong PIERGIORGIO Picozzo DAI JianPing 2018Science China(Technological Sciences)2018,61,5:33
2Relationship between types of urban forest and PM_(2.5) capture at three growth stages of leaves显示文摘Particulate matter diameter ≤ 2.5 μm(PM2.5) causes direct harm to human health. Finding forms of urban forest systems that with the ability to reduce the amount of particulate matter in air effectively is the aim of this study. Five commonly cultivated kinds of urban forest types were studied in Beijing city at three stages of leaf growth. Results show that the urban forest system is capable of storing and capturing dust from the air. The types of shrubs and broadleaf trees that have the ability to capture PM2.5from the air are most effective when leaves have fully developed. In the leafless season, the conifer and mixed tree types are the most effective in removing dust from the air. For all kinds of forest types and stages of leaf growth, the PM2.5concentration is highest in the morning but lower in the afternoon and evening. Grassland cannot control particles suspended in the air,but can reduce dust pollution caused by dust from the ground blown by the wind back into the air.Thithanhthao Nguyen Xinxiao Yu Zhenming Zhang Mengmeng Liu Xuhui Liu 2015Journal of Environmental Sciences2015,27,1:30
3Estimation of China’s terrestrial ecosystem carbon sink:Methods,progress and prospects显示文摘China announced its national goal to reach the peak of carbon emission by 2030 and achieve carbon neutrality by 2060,during the General Assembly of the United Nations in September 2020.In this context,the potential of the carbon sink in China’s terrestrial ecosystems to mitigate anthropogenic carbon emissions has attracted unprecedented attention from scientific communities,policy makers and the public.Here,we reviewed the assessments on China’s terrestrial ecosystem carbon sink,with focus on the principles,frameworks and methods of terrestrial ecosystem carbon sink estimates,as well as the recent progress and existing problems.Looking forward,we identified critical issues for improving the accuracy and precision of China’s terrestrial ecosystem carbon sink,in order to serve the more realistic policy making in pathways to achieve carbon neutrality for China.Shilong PIAO Yue HE Xuhui WANG Fahu CHEN 2022Science China Earth Sciences2022,65,4:30
4Cellular and Molecular Immunopathogenesis of Ulcerative Colitis显示文摘Ulcerative 大肠炎(UC ) 是直肠、结肠的 mucosa 的煽动性的疾病并且似乎源于在危险性基因,环境和免疫系统之间的相互作用的一个复杂系列。mucosal 免疫系统的各种各样的部件在 UC 的 immunopathogenesis 被含有。从动物模型的证据也建议对宿主的共栖的 microflora 的改变的有免疫力的回答在 UC 的发展起一个中央作用。那么在这评论,我们阐明从四个方面在疾病的 immunopathogenesis 被含有的房间和分子:在肠的抗原,树枝状的房间,在 UC 敲相似受体和 NF-B。Suzhen Zhang Xuhui Zhao Dechun Zhang 2006Cellular & Molecular Immunology2006,3,1:25
5Perspectives on studies on soil carbon stocks and the carbon sequestration potential of China显示文摘Soil carbon stocks and sequestration have been given a lot of attention recently in the study of terrestrial ecosystems and global climate change.This review focuses on the progress made on the estimation of the soil carbon stocks of China,and the characterization of carbon dynamics of croplands with regard to climate change,and addresses issues on the mineralization of soil organic carbon in relation to greenhouse gas emissions.By integrating existing research data,China's total soil organic carbon(SOC) stock is estimated to be 90 Pg and its inorganic carbon(SIC) stock as 60 Pg,with SOC sequestration rates in the range of 20-25 Tg/a for the last two decades.An estimation of the biophysical potential of SOC sequestration has been generally agreed as being 2 Pg over the long term,of which only 1/3 could be attainable using contemporary agricultural technologies in all of China's croplands.Thus,it is critical to enhance SOC sequestration and mitigate climate change to improve agricultural and land use management in China.There have been many instances where SOC accumulation may not induce an increased amount of decomposition under a warming scenario but instead favor improved cropland productivity and ecosystem functioning.Furthermore,unchanged or even decreased net global warming potential(GWP) from croplands with enhanced SOC has been reported by a number of case studies using life cycle analysis.Future studies on soil carbon stocks and the sequestration potential of China are expected to focus on:(1) Carbon stocks and the sequestration capacity of the earths' surface systems at scales ranging from the plot to the watershed and(2) multiple interface processes and the synergies between carbon sequestration and ecosystem productivity and ecosystem functioning at scales from the molecular level to agro-ecosystems.Soil carbon science in China faces new challenges and opportunities to undertake integrated research applicable to many areas.ZHENG JuFeng CHENG Kun PAN GenXing Pete SMITH LI LianQing ZHANG XuHui ZHENG JinWei HAN XiaoJun DU YanLing 2011Chinese Science Bulletin2011,56,35:24
6Organic carbon stratification and size distribution of three typical paddy soils from Taihu Lake region,China显示文摘为中国的持续农业开发现实主义的土壤碳(C) 隐遁策略依靠数量,保留和在水稻土存储的 C 的周转率的精确估计。到日期的可得到的 C 估计是主要为 tilled 和灌溉洪水的表面表层土(ca。30 厘米) 。自从器官的碳(SOC ) 通常显示出的土壤,如此的估计不能被用来外推到 100 厘米的土壤深度有深度的锋利的减少。在这研究,合成土壤样品在泰胡·莱克区域从三代表性的水稻土在几深度被收集到 100 厘米,中国。在侧面玷污器官的碳分发,在总数尺寸,部分被决定。当 SOC 与深度指数地减少了到 100 厘米时,结果显示出那,全部的 SOC 的一个实质的比例(30%40%) 在 30 厘米深度下面被存储。在充实碳的稻表层土, SOC 被发现在 2 0.25 和 0.25 0.02 公里总数尺寸部分优先地积累。? 粗糙的微总数的部分的 13C 分析证明在稻表层土的 C 层化的高度与打火机的出现一致 ? 1313C 在上面 30 厘米深度。这些结果建议在侧面以内的层化关于泥土和铁 oxyhydrates 分布与水稻土的不同 pedogenetical 类型改变的那 SOC。在水稻土系统的总数的沙大小的部分可以在碳隐遁和周转起一个很重要的作用,对另外的学习农业系统不一样。PAN Genxing WU Laosheng LI Lianqing ZHANG Xuhui GONG Wei WOOD Yvonne 2008Journal of Environmental Sciences2008,20,4:21
7The impacts of climate extremes on the terrestrial carbon cycle:A review显示文摘The increased frequency of climate extremes in recent years has profoundly affected terrestrial ecosystem functions and the welfare of human society. The carbon cycle is a key process of terrestrial ecosystem changes. Therefore, a better understanding and assessment of the impacts of climate extremes on the terrestrial carbon cycle could provide an important scientific basis to facilitate the mitigation and adaption of our society to climate change. In this paper, we systematically review the impacts of climate extremes(e.g. drought, extreme precipitation, extreme hot and extreme cold) on terrestrial ecosystems and their mechanisms. Existing studies have suggested that drought is one of the most important stressors on the terrestrial carbon sink, and that it can inhibit both ecosystem productivity and respiration. Because ecosystem productivity is usually more sensitive to drought than respiration, drought can significantly reduce the strength of terrestrial ecosystem carbon sinks and even turn them into carbon sources. Large inter-model variations have been found in the simulations of drought-induced changes in the carbon cycle, suggesting the existence of a large gap in current understanding of the mechanisms behind the responses of ecosystem carbon balance to drought, especially for tropical vegetation. The effects of extreme precipitation on the carbon cycle vary across different regions. In general, extreme precipitation enhances carbon accumulation in arid ecosystems, but restrains carbon sequestration in moist ecosystems. However, current knowledge on the indirect effects of extreme precipitation on the carbon cycle through regulating processes such as soil carbon lateral transportation and nutrient loss is still limited. This knowledge gap has caused large uncertainties in assessing the total carbon cycle impact of extreme precipitation. Extreme hot and extreme cold can affect the terrestrial carbon cycle through various ecosystem processes. Note that the severity of such climate extremes depends greatly on their timing, which needs to be investigated thoroughly in future studies. In light of current knowledge and gaps in the understanding of how extreme climates affect the terrestrial carbon cycle, we strongly recommend that future studies should place more attention on the long-term impacts and on the driving mechanisms at different time scales.Studies based on multi-source data, methods and across multiple spatial-temporal scales, are also necessary to better characterize the response of terrestrial ecosystems to climate extremes.Shilong PIAO Xinping ZHANG Anping CHEN Qiang LIU Xu LIAN Xuhui WANG Shushi PENG Xiuchen WU 2019Science China Earth Sciences2019,62,10:16
8SWMM-based methodology for block-scale LID-BMPs planning based on site-scale multi-objective optimization: a case study in Tianjin显示文摘最好的管理惯例(LID-BMPs ) 的低影响发展类型试图减轻城市的 stormwater 流量并且以一个节俭、 eco 友好的方法减少污染物质负担并且在现代城市的 stormwater 管理成为了一颗全球担心。新方法论基于为块规模 LID-BMPs 计划的 stormwater 管理模型(SWMM ) 被开发。在地点规模的综合 LID-BMP 链布局优化在全部块规模与情形分析打包的这个方法城市的区域。非统治的排序的基因算法(NSGA-II ) 成功地通过大蟒被联合到 SWMM 完成地点规模优化过程。研究区域的不同的盖情形根据优化 LID-BMP 链布局被设计。认为流量是数量索引,污染物质负担,和构造费用的多索引评估同时帮助了作为计划计划的期末考试选择划算的情形。在天津的案例研究,中国,被进行表明建议方法论。结果显示出全部的流量体积, 22%-46% 山峰流动减小效率,和超过 32% 污染物质移动率的那超过 75% 控制率被完成。坚韧性分析显示选择最后的计划计划与改变的重量价值是更加柔韧的。Te Xu Haifeng Jia Zheng Wang Xuhui Mao Changqing Xu 2017Frontiers of Environmental Science & Engineering2017,11,4:13
9Spiral Steel Wire Based Fiber-Shaped Stretchable and Tailorable Triboelectric Nanogenerator for Wearable Power Source and Active Gesture Sensor显示文摘Continuous deforming always leads to the performance degradation of a flexible triboelectric nanogenerator due to the Young’s modulus mismatch of different functional layers.In this work,we fabricated a fiber-shaped stretchable and tailorable triboelectric nanogenerator(FST-TENG)based on the geometric construction of a steel wire as electrode and ingenious selection of silicone rubber as triboelectric layer.Owing to the great robustness and continuous conductivity,the FST-TENGs demonstrate high stability,stretchability,and even tailorability.For a single device with ~6 cm in length and ~3 mm in diameter,the open-circuit voltage of ~59.7 V,transferred charge of ~23.7 nC,short-circuit current of ~2.67 μA and average power of ~2.13 μW can be obtained at 2.5 Hz.By knitting several FST-TENGs to be a fabric or a bracelet,it enables to harvest human motion energy and then to drive a wearable electronic device.Finally,it can also be woven on dorsum of glove to monitor the movements of gesture,which can recognize every single finger,different bending angle,and numbers of bent finger by analyzing voltage signals.Lingjie Xie Xiaoping Chen Zhen Wen Yanqin Yang Jihong Shi Chen Chen Mingfa Peng Yina Liu Xuhui Sun 2019Nano-Micro Letters2019,11,3:13
10Pharmacokinetics of magnesium lithospermate B after intravenous administration in beagle dogs显示文摘AIM: To develop a specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the pharmacokinetic study of magnesium lithospermate B (MLB), and study the pharmacokinetics of MLB after iv administration in beagle dogs.. METHODS: Each beagle dog was iv administered MLB 3, 6, and 12 mg/kg random. The serum drug concentration was determined by specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays. The pharmacokinetic parameters were calculated by Drug and Statistics version 1.0 program.RESULTS: The calibration curve for MLB was linear over a range of 16-4096 μg/L with coefficients of correlation>0.999. The intra- and inter-day precisions (CV) of analysis were <10 %, and accuracy ranged from 90 % to 113%. After iv administration of MLB at the doses of 3, 6, and 12 mg/kg, the CO values for MLB were estimated to be of 24, 47, and 107 mg/L, respectively. The AUC increased with the increasing doses for iv administration, and the mean AUC0-4 values were 109.3, 247.9, and 582.4 mg·min·L^-1, respectively. MLB was distributed and eliminated quickly from central compartment, the mean T1/2a values for MLB at doses of 3, 6, 12 mg/kg were 2.2, 2.7, and 2.9 rain,and the mean T1/2β values were 43, 42, and 42 min, respectively. CONCLUSION: This LC-MS/MS method is rapid, sensitive, and specific for the pharmacokinetic study of MLB. The kinetic process of MLB in beagle dogs in vivo was best fitted to a two-compartment model. For iv administration, the pharmacokinetic parameters of CO and AUC have good linearity among the doses, and MLB was distributed and eliminated quickly in beagle dogs.Xiao-chuan LI, Chen YU, Wei-kang SUN, Gang-yi LIU, Jing-ying JIA, Yi-ping WANGDepartment of Pharmacology, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203 Central Laboratory, Shanghai Xuhui Central Hospital, Shanghai 200002, China 2004Acta Pharmacologica Sinica2004,25,11:13
11The earthquake-related disturbances in ionosphere and project of the first China seismo-electromagnetic satellite显示文摘Based on the case studies and statistical analysis of earthquake-related ionospheric disturbances mainly from DEMETER satellite,ground-based GPS and ionosounding data,this paper summarizes the statistical characteristics of earthquake-related ionospheric disturbances,including electromagnetic emissions,plasma perturbations and variation of energetic particle flux.According to the main results done by Chinese scientists, fusing with the existed study from global researches,seismo-ionospheric disturbances usually occurred a few days or hours before earthquake occurrence.Paralleling to these case studies,lithosphere-atmosphere-ionosphere (LAI) coupling mechanisms are checked and optimized.A thermo-electric model was proposed to explain the seismo-electromagnetic effects before earthquakes.A propagation model was put forward to explain the electromagnetic waves into the ionosphere.According to the requirement of earthquake prediction research,China seismo-electromagnetic satellite,the first space-based platform of Chinese earthquake stereoscopic observation system,is proposed and planned to launch at about the end of 2014.It focuses on checking the LAI model and distinguishing earthquake-related ionospheric disturbance.The preliminary design for the satellite will adopt CAST-2000 platform with eight payloads onboard.It is believed that the satellite will work together with the ground monitoring network to improve the capability to capture seismo-electromagnetic information,which is beneficial for earthquake monitoring and prediction researches.Xuhui Shen Xuemin Zhang Lanwei Wang Huaran Chen Yun Wu Shigeng Yuan Junfeng Shen Shufan Zhao Jiadong Qian Jianhai Ding 2011Earthquake Science2011,24,6:13
12Introduction to special section on the China Seismo-Electromagnetic Satellite and initial results显示文摘1.Introduction The China Seismo-Electromagnetic Satellite (CSES), which is also called ZhangHeng-1 (ZH-1), is the first Chinese space-borne platform dedicated to geophysical field measurement andearthquake monitoring by detecting variations in the electromagnetic environment of space. The CSES was launched successfully at15:51 on February 2, 2018, at China’s Jiuquan Satellite Launching Center.XuHui Shen Qiu-Gang Zong XueMin Zhang 2018Earth and Planetary Physics2018,2,6:13
13Photosynthetic and Respiratory Acclimation to Experimental Warming for Four SpeCies in a Tallgrass Prairie Ecosystem显示文摘全球温度被 0.6 度 C 在过去的世纪增加了并且被预言在这个世纪底由 1.4-5.8 度 C 增加。全球温暖将在高草种类上有什么影响,是不清楚的。在现在的学习,我们检验了光合的率( Pn )和叶呼吸在翠菊 ericoides 的黑暗( Rd )评估的叶网, Ambrosiapsilostachya ,向日葵女人是并且响应在大平原(俄克拉何马)的 atallgrass 大草原生态系统的试验性的温暖的 Sorghastrum 坚果 ans ,美国,在 2000-2001 的秋天。Warminghas 自从 1999 年 11 月 21 日,与红外线的加热器实现了。Pn 在春天显著地增加了,在早秋天减少了,并且没在与控制相比温暖下面在四种在夏天和晚秋变化。四种的 Rd 显著地增加了直到仲夏然后没在温暖下面变化。测量温度反应为 H.mollis 和 S 由 2.32 和 4.59 度 C 温暖增加了的 Pnshowed 弄弯 Pn (Topt ) 的最适温度。坚果 ans,分别地在 8 月,而在 5 月和 9 月没有变化,并且一。ericoides 和 A。psilostachya 也没在任何 3 个月显示出变化。然而,在显示出的最适温度(Popt ) 的 Pn 在 5 月和 Augustfor 在 9 月和没有规定击倒规定所有四种。Rd 的温度反应曲线说明 Rd 的温度敏感, Q10,与对照小区相比在温暖的阴谋是更低的除了在 8 月的 A.ericoides,而为所有四种在 5 月和 9 月没有变化。现在的学习的 Theresults 显示光合、呼吸的环境适应与种类并且在季节之中变化,发生在中间成长的季节并且不在早、迟了的生长期……Xuhui Zhou Xiaozhong Liu Linda L. Wallace Yiqi Luo 2007Journal of Integrative Plant Biology2007,49,3:11
14Thermal physical properties and key influence factors of phase change emulsion显示文摘Latent functionally thermal fluids (LFTF) are a novel kind of heat storage and heat transfer fluids that in- clude phase change microcapsule slurry and phase change emulsion (PCE). They have much greater apparent specific heats and higher heat transfer abilities in the phase change temperature range than conventional single-phase heat transfer fluids such as water. Thus they are advantageous in the field of the convective heat transfer enhancement and energy transport. In this paper, some thermal physical prop- erties such as viscosity, fusion heat and apparent specific heat (cp) are measured, and the influences of some factors (such as selection of surfactants, preparation method, temperature, mixing ratio of surfactants and mass concentration of phase change material) on them are discussed. The study shows that: 1) the viscosity of the PCE prepared in the present work is lower than that reported in the literature; 2) its ap- parent specific heat value for the phase change temperature region is high and proportionally increases with the concentration of phase change material.XUHui YANGRui ZHANGYinping HUANGZhe LINJia WANGXin 2005Chinese Science Bulletin2005,50,1:9
15Flexible self-charging power units for portable electronics based on folded carbon paper显示文摘对便携式的电子学的迫切要求支持了高效率、持续、甚至可拉长的自我控告的力量来源的发展。在这个工作,我们建议为从人的运动和力量便携式计算机电子学收获机械精力基于合拢的碳(FC ) 统一纸的灵活自我控告的力量。现在的单位主要由摩擦电 nanogenerator (FC-TENG ) 和 supercapacitor (FC-SC ) 组成,基于合拢的复写纸精力 harvester 和存储设备分别地。这个有利几何图案向高幼仔模量复写纸提供优秀 stretchability 并且使力量单位能甚至在严重变丑下面工作,扭动,并且滚动,例如弯曲。另外,张力的紧张能被调节合拢三角的复写纸的合拢的角度最大化。而且,包装设备的防水性质使它可洗,保护它免受人的汗的伤害,并且使它能在严厉环境工作。最后,同样准备的自我控告的力量单位被把它放在人的身体上从手拍,踩的脚,并且手臂接触成功地驱动一块电子手表收获机械精力测试。这个工作表明可拉长的自我控告的力量单位的出色的潜力,它将进一步为便携 / 便携式的电子学支持高幼仔模量材料的发展。Changjie Zhou Yanqin Yang Na Sun Zhen Wen Ping Cheng Xinkai Xie Huiyun Shao Qingqing Shen Xiaoping Chen Yina Liu Zhong Lin Wang Xuhui Sun 2018Nano Research2018,11,8:9
16Curative effect of Dingqi analgesic patch on cancer pain:a single-blind randomized controlled trail显示文摘OBJECTIVE:To observe the curative effect of an acupoint application with a Dingqi analgesic patch on moderate to severe pain caused by liver cancer.METHODS:Forty patients with moderate to severe pain caused by liver cancer were randomly divided intoatreatmentgroup(TG)andacontrolgroup(CG).Patients with moderate pain were given 100 mg qd of a sustainably released tablet of tramadol hydrochloride;patientswithseverepainweregiven4.2mg q3d of the fentanyl transdermal system.The ashi points Ganshu(BL 18),Danshu(BL 19) and Qimen(LR 14) were chosen for the acupoint application intervention.CG patients were given a sham patch and TG patients were given a Dingqi analgesic patch.A visual analogue scale(VAS) was used before treatment and after 1,3,6,9 and 12 days of treatment.The Karnofsky score was measured before treatment and after 12 days of treatment.Any main adverse reactions(e.g.nausea,constipation,dizziness and headache) were recorded after 6 and 12 days of treatment.Any skin side effects(i.e.skin irritation and allergic reactions) were recorded.RESULTS:The VAS in TG was significantly lower than that in CG after 3,6,9 and 12 days of treatment(P<0.05).There was no significant difference in the Karnofsky score before treatment and after 12 days of treatment between CG and TG.There were also no significant differences in the main adverse reactions or skin side effects after 6 and 12 days of treatment between CG andTG(P>0.05).CONCLUSION:The Dingqi analgesic patch can enhance the analgesic effect of tramadol and fentanyl.Changjun Wang Wei Tan Xuhui Huang Tingting Fu Juze Lin Junmin Bu Guojian Wei Yu Du 2013Journal of Traditional Chinese Medicine2013,33,2:9
17Triboelectric–Electromagnetic Hybrid Generator for Harvesting Blue Energy显示文摘Progress has been developed in harvesting lowfrequency and irregular blue energy using a triboelectric–electromagnetic hybrid generator in recent years. However,the design of the high-efficiency, mechanically durable hybrid structure is still challenging. In this study, we report a fully packaged triboelectric–electromagnetic hybrid generator(TEHG), in which magnets were utilized as the trigger to drive contact–separation-mode triboelectric nanogenerators(CS-TENGs) and coupled with copper coils to operate rotary freestanding-mode electromagnetic generators(RF-EMGs). The magnet pairs that produce attraction were used to transfer the external mechanical energy to the CS-TENGs, and packaging of the CS-TENGpart was achieved to protect it from the ambient environment. Under a rotatory speed of 100 rpm, the CS-TENGs enabled the TEHG to deliver an output voltage, current,and average power of 315.8 V, 44.6 μA, and ~ 90.7 μW,and the output of the RF-EMGs was 0.59 V, 1.78 m A, and 79.6 μW, respectively. The cylinder-like structure made the TEHG more easily driven by water flow and demonstrated to work as a practical power source to charge commercial capacitors. It can charge a 33μF capacitor from 0 to 2.1 V in 84 s, and the stored energy in the capacitor can drive an electronic thermometer and form a self-powered water-temperature sensing system.Huiyun Shao Ping Cheng Ruixuan Chen Lingjie Xie Na Sun Qingqing Shen Xiaoping Chen Qianqian Zhu Yi Zhang Yina Liu Zhen Wen Xuhui Sun 2018Nano-Micro Letters2018,10,3:9
18Spatial and temporal distribution of acetochlor in sediments and riparian soils of the Songhua River Basin in northeastern China显示文摘The Songhua River Basin is a burgeoning agricultural area in the modern times in China.Particularly in recent years,increasing chemical fertilizers and pesticides have been applied with the development of agricultural production.However,the situation of nonpoint source pollution (NSP) from agricultural production in this basin is still obscure.In order to solve the problem,the occurrence and distribution of acetochlor in sediments and riparian soils of the Songhua River Basin before rain season and after rain season were investigated.In addition,total organic carbon was analyzed.The result showed that the concentration of acetochlor ranged from 0.47 to 11.76 μg/kg in sediments and 0.03 to 709.37 μg/kg in riparian soils.During the high flow period in 2009,the mean concentration was 4.79 μg/kg in sediments and 0.75 μg/kg in riparian soils,respectively.Similarly,the mean concentration was 2.53 μg/kg in sediments and 61.36 μg/kg in riparian soils,during the average flow period in 2010.There was a significant correlation between the concentration of acetochlor and total organic carbon in surface sediments.Moreover,the distribution of acetochlor in sediments of the Songhua River was significantly correlated to land use and topography of the watershed.The investigated data suggested that the concentration of acetochlor in the Songnen Plain and the Sanjiang Plain was higher than that in the other areas of the basin,and riparian buffering zones in these areas had been destroyed by human activities.The optimal agricultural measures to alleviate the contamination of pesticides should be adopted,including controlling agricultural application of acetochlor and ecological restoration of riparian buffering strips.Xiaoyin Sun Qixing Zhou Wenjie Ren Xuhui Li Liping Ren 2011Journal of Environmental Sciences2011,23,10:9
19Characteristics of Turbulent Transfer during Episodes of Heavy Haze Pollution in Beijing in Winter 2016/17显示文摘We analyzed the structure and evolution of turbulent transfer and the wind profile in the atmospheric boundary layer in relation to aerosol concentrations during an episode of heavy haze pollution from 6 December 2016 to 9 January 2017. The turbulence data were recorded at Peking University's atmospheric science and environment observation station. The results showed a negative correlation between the wind speed and the PM2.5 concentration. The turbulence kinetic energy was large and showed obvious diurnal variations during unpolluted(clean) weather, but was small during episodes of heavy haze pollution. Under both clean and heavy haze conditions, the relation between the non-dimensional wind components and the stability parameter z/L followed a 1/3 power law, but the normalized standard deviations of the wind speed were smaller during heavy pollution events than during clean periods under near-neutral conditions. Under unstable conditions, the normalized standard deviation of the potential temperatureσ_θ/|θ_*| was related to z/L, roughly following a –1/3 power law, and the ratio during pollution days was greater than that during clean days. The three-dimensional turbulence energy spectra satisfied a –2/3 power exponent rate in the high-frequency band. In the low-frequency band, the wind velocity spectrum curve was related to the stability parameters under clear conditions, but was not related to atmospheric stratification under polluted conditions. In the dissipation stage of the heavy pollution episode, the horizontal wind speed first started to increase at high altitudes and then gradually decreased at lower altitudes. The strong upward motion during this stage was an important dynamic factor in the dissipation of the heavy haze.Yan REN Shuwen ZHENG Wei WEI Bingui WU Hongsheng ZHANG Xuhui CAI Yu SONG 2018Journal of Meteorological Research2018,32,1:9
20A Study on the Xenia Effect in Castanea henryi显示文摘The xenia effect results in pollen affecting the setting rate and the appearance and quality of fruits. To further understand this phenomenon,we investigated the xenia effect in Castanea henryi using the cultivars ‘Huali 1', ‘Huali 2', ‘Huali 3', and ‘Huangzhen' as materials. Twenty combinations of self-, cross-, and natural pollination were undertaken in a chestnut orchard in Chenzhou City, Hunan Province, China. Significant differences were observed among the pollination combinations in terms of the time of fruit ripening, rate of fruit setting, size of the barbed shell and nut, and content of soluble sugars, fats, proteins, amylose, and vitamin C. No significant differences were observed with regard to nut rate,content of total starch, and moisture content. The fruit quality of the 20 pollination combinations was evaluated using a subordinate function method,and showed that Huali 2 × Huali 3 was the best combination, and Huangzhen × Huangzhen was the most ineffective combination. Therefore, we recommend the combination of Huali 2 × Huali 3 for the future production of C. henryi.ZHANG Xuhui YUAN Deyi ZOU Feng FAN Xiaoming TANG Jing ZHU Zhoujun 2016Horticultural Plant Journal2016,2,6:9
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