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425篇 您的检索式:作者名="Dongsheng Li"
    题名 作者 年代 出处 被引量
1Spatial patterns and driving forces of land use change in China during the early 21st century显示文摘Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the 'Grain for Green' policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of 'Western Development', 'Revitalization of Northeast', coupled with rapidly economic development during this period.LIU Jiyuan ZHANG Zengxiang XU Xinliang KUANG Wenhui ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhen YU Dongsheng WU Shixin JIANG Nan 2010Journal of Geographical Sciences2010,20,4:154
2Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s显示文摘Land-use/land-cover 变化(LUCC ) 有连接到人和自然相互作用。瓷器 Land-Use/cover 数据集(CLUD ) 从 1980 年代末在 5 年的间隔定期被更新到 2010,与基于 Landsat TMETM+ 图象的标准过程。陆地使用动态区域化方法被建议分析主要陆地使用变换。在国家规模的陆地使用变化的空间与时间的特征,差别,和原因然后被检验。主要调查结果如下被总结。越过中国的陆地使用变化(LUC ) 在最后 20 年(19902010 ) 里在空间、时间的特征显示了一个重要变化。农田变化的区域在南方减少了并且在北方,而是仍然是的全部的区域增加了几乎未改变。回收农田从东北被转移到西北。布满建筑物陆地很快膨胀了,主要在东方被散布,并且逐渐地展开到中央、西方的中国。树林首先减少了,然后增加但是荒芜的区域是反面。草地继续减少。在中国的 LUC 的不同空间模式被发现在之间迟了第 20 世纪并且早第 21 世纪。原版 13 个 LUC 地区在一些地区被边界的变化由 15 个单位代替。包括的这些变化(1 ) 的主要空间特征加速的扩大布满建筑物在 Huang-Huai-Hai 区域,东南的沿海的区域,长江的中流区域,和四川盆登陆;(2 ) 从东北中国和东方内部蒙古在北方转移了陆地开垦到绿洲在西北中国的农业区域;(3 ) 从在到稻的东北中国的喂雨的农田的连续转变回答;并且(4 ) 为在内部蒙古,黄土高原,和西南的多山的区域的南部的农业牧剧的交错群落的格林工程的谷物的有效性。在最后二十年,尽管在北方的气候变化在农田影响了变化,政策规定和经济驱动力仍然是越过中国的 LUC 的主要原因。在第 21 世纪的第一十年期间,在陆地使用模式驾驶了变化的人为的因素从单程的陆地开发转移了强调到开发和保存。动态区域化方法被用来在单位的 zoning 边界,地区的内部特征,和生长和减少的空间模式分析变化。结果揭示了变化过程的模式,也就是 LUC 的过程和在在不同阶段的特征的地区性的差别。地区的生长和减少在这动态 LUC zoning,在统一边界的变化,和在前者和后者十年之间的变化紧张的特征期间被检验。在为在不同类型和陆地使用的不同区域的变化的陆地使用和原因的模式和过程之间的其他的转变的模式被探索。LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 2014Journal of Geographical Sciences2014,24,2:245
3Mechanism for the formation of the January 2013 heavy haze pollution episode over central and eastern China显示文摘In January 2013,a long-lasting episode of severe haze occurred in central and eastern China,and it attracted attention from all sectors of society.The process and evolution of haze pollution episodes were observed by the'Forming Mechanism and Control Strategies of Haze in China'group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network.The characteristics and formation mechanism of haze pollution episodes were discussed.Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei(Jing-Jin-Ji)area;the two most severe episodes occurred during 9–15 January and 25–31 January.During these two haze pollution episodes,the maximum hourly PM2.5mass concentrations in Beijing were 680 and 530μg m 3,respectively.The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area,such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing.The external cause of the severe haze episodes was the unusual atmospheric circulation,the depression of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions.However,the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols,which contributed to the'explosive growth'and'sustained growth'of PM2.5.Particularly,the abnormally high amount of nitric oxide(NOx)in the haze episodes,produced by fossil fuel combustion and vehicle emissions,played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide(SO2)to sulphate aerosols.Furthermore,gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles,which can change the particle’s size and chemical composition.Consequently,the proportion of secondary inorganic ions,such as sulphate and nitrate,gradually increased,which enhances particle hygroscopicity and thereby accelerating formation of the haze pollution.WANG YueSi YAO Li WANG LiLi LIU ZiRui JI DongSheng TANG GuiQian ZHANG JunKe SUN Yang HU Bo XIN JinYuan 2014Science China Earth Sciences2014,57,1:189
4Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future.Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang 2020National Science Review2020,7,8:51
5Transmission Dynamics of an Outbreak of the COVID-19 Delta Variant B.1.617.2——Guangdong Province,China,May-June 2021显示文摘On May 21,2021,a local case of coronavirus disease 2019(COVID-19)was confirmed in a 75-year-old woman(experienced onset of symptoms on May 18)in Liwan District,Guangzhou City,Guangdong Province,China.The number of infections has increased in the following 10 days and led to 5 generations of transmission.Meng Zhang Jianpeng Xiao Aiping Deng Yingtao Zhang Yali Zhuang Ting Hu Jiansen Li Hongwei Tu Bosheng Li Yan Zhou Jun Yuan Lei Luo Zimian Liang Youzhi Huang Guoqiang Ye Mingwei Cai Gongli Li Bo Yang Bin Xu Ximing Huang Yazun Cui Dongsheng Ren Yanping Zhang Min Kang Yan Li 2021China CDC weekly2021,3,27:51
6Correlation of E-selectin gene polymorphisms with risk of ischemic stroke A meta-analysis显示文摘OBJECTIVE: To investigate the association of E-selectin S128R polymorphisms with ischemic stroke. DATA SOURCES: A computer-based online search was conducted in PubMed, Elsevier, Ovid Database, the China National Knowledge Infrastructure, and Wanfang Database between January 1998 and December 2010. STUDY SELECTION: Case-controlled studies addressing the association of the E-selectin polymorphism and ischemic stroke were included in this review. The genotype distribution complied with the Hardy-Weinberg genetic equilibrium. The included reports were evaluated by two authors for strict quality screening. Meta-analysis software, REVMAN 5.1, was used to investigate heterogeneity, pooled odds ratio (OR) and 95% confidence interval (CI) in individual studies. MAIN OUTCOME MEASURES: Genotype and allele distributions at the E-selectin S128R site. RESULTS: Six case-controlled studies were included after screening and application of inclusion and exclusion criteria. There was no heterogeneity in the genotype and allele frequencies, and no publication bias was found. Meta-analysis of the pooled data showed that the OR value of the (AC+CC)/AA genotype was 1.93 (95% CI: 1.55-2.41, Z = 5.80, P < 0.000 01), and the OR for the C/A allele was 1.80 (95% CI: 1.47-2.22, Z = 5.59, P < 0.000 01) in the ischemic stroke group, compared with control group. Results of pooled data in Chinese subjects showed that the OR value of (AC+CC)/AA was 2.36 (95% CI: 1.68-3.31, Z = 4.99, P < 0.000 01), and the OR value of the C/A allele was 2.25 (95% CI: 1.63-3.12, Z = 4.89, P < 0.000 01). CONCLUSION: Polymorphism of E-selectin S128R was significantly associated with susceptibility to ischemic stroke; the AC and CC genotypes as well as the C allele may be factors associated with susceptibility to ischemic stroke.Qingli Sun Yu Fu Aping Sun Yanhong Shou Mei Zheng Xiaogang Li Dongsheng Fan 2011Neural Regeneration Research2011,6,22:46
7In vitro derivation of functional insulin-producing cells from human embryonic stem cells显示文摘为人的胚胎的茎(ES ) 的自强和区别的能力细胞为对待类型 Idiabetes mellitus 为胰腺的贝它细胞的产生使他们成为潜在的来源。这里,我们报导一最新发展了并且有效方法,在aserum免费的系统执行了,区分进生产胰岛素的 cells.Activin A 的导致的人的 ES 房间它在起始的阶段被使用从人的 EScells 导致权威的内胚叶区别,是由权威的内胚叶标记 Sox17 和 Brachyury.Further 的表示检测了, all-trans retinoic 酸( RA )被用来支持胰腺的区别,由早胰腺的抄写因素 pdx1 和 hlxb9 的表示显示了。在成熟 inDMEM/F12 以后有 bFGF 和菸碱的没有浆液的媒介,区分的房间表示了小岛特定的标记象 C 肽,胰岛素,胰高血糖素和 glut2 那样。百分比 ofC-peptide-positive 房间超过了 15% 。由这些房间的胰岛素和 C 肽的分泌物在葡萄糖层次对应于变化。当移植了进肾的囊时, ofStreptozotocin (STZ ) 对待裸体老鼠,这些区分的人的 ES 房间熬过并且维持贝它房间标记基因的表示包括 C 肽, pdx1, glucokinase, nkx6.1, IAPP, pax6and Tcf1。百分之三十只移植裸体老鼠展出了 stableeuglycemia 的明显的恢复;并且改正的显型被支撑超过六个星期。我们的新方法为学习人的胰开发的机制提供一个有希望的试管内区别模特儿并且说明为类型 Idiabetes mellitus 的处理使用人的 ES 房间的潜力。Wei Jiang Yan Shi Dongxin Zhao Song Chen Jun Yong Jing Zhang Tingting Qing Xiaoning Sun Peng Zhang Mingxiao Ding Dongsheng Li Hongkui Deng 2007Cell Research2007,17,4:38
8Variability and reduction of atmospheric pollutants in Beijing and its surrounding area during the Beijing 2008 Olympic Games显示文摘The Beijing-Tianjin-Hebei Atmospheric Environment Monitoring Network was established by the Institute of Atmospheric Physics,Chinese Academy of Sciences.The goals of the network were to monitor and provide warnings of the atmospheric quality in Beijing and its surrounding area during the Beijing 2008 Olympic Games.The results showed that the atmospheric complex pollution exhibited high concentrations of ozone and fine particles and oxidation in summer,with a ubiquitous regional source.The regional mean concentrations of SO2,PM2.5,NO2,and O3_8h max(the maximum daily 8 h mean) and Ox were 22±11,90±40,25±5,136±35 and 112±21 μg/m3 in summer,respectively.During the Olympic Games,the mean concentration of SO2,PM2.5,NO2,O3_8h max,and Ox were 12.5±4,56±28,23±4,114±29,95±17 μg/m3 in the region,respectively,and fell by 51.0%,43.7%,13%,20.2%,and 18.9%,respectively,compared to the prophase mean before the Olympic Games.The concentration of atmospheric pollutants declined significantly and achieved the 'Green Olympics' control goal of air quality.After the Olympic Games,SO2,PM2.5 and NOx increased significantly as the temporary atmospheric pollution control measures were terminated.XIN JinYuan WANG YueSi TANG GuiQian WANG LiLi SUN Yang WANG YingHong HU Bo SONG Tao JI DongSheng WANG WeiFeng LI Liang LIU GuangRen 2010Chinese Science Bulletin2010,55,18:30
9Predicting lifetime risk for developing atherosclerotic cardiovascular disease in Chinese population:the China-PAR project显示文摘Evidence on the lifetime risk for atherosclerotic cardiovascular disease(ASCVD) is insufficient;yet,estimating an individual's lifetime risk allows for a comprehensive assessment of ASCVD burden.We developed and validated lifetime risk prediction equations for ASCVD using four large and ongoing prospective cohorts of Chinese,the China-PAR project(Prediction for ASCVD Risk in China).Sexspecific equations were developed using two cohorts(as the derivation cohort) of 21,320 participants.Two other independent cohorts with 14,123 and 70,838 participants were used for their external validation,respectively.We evaluated both calibration and discrimination measures for model performance.Furthermore,we estimated ASCVD-free years lost or excess absolute risk attributable to high 10-year risk(!10.0%) and/or high lifetime risk(!32.8%).After 12.3 years' follow-up of the derivation cohort,1048 ASCVD events and 1304 non-ASCVD deaths were identified.Our sex-specific equations had good internal validation,with discriminant C statistics of 0.776(95% confidence interval [CI]:0.757–0.794) and 0.801(95% CI:0.778–0.825),and calibration χ~2 of 9.2(P = 0.418) and 5.6(P = 0.777) for men and women,respectively.Good external validation was also demonstrated with predicted rates closely matched to the observed ones.Compared with men having both low 10-year and low lifetime risk,men would develop ASCVD 3.0,4.6 and 8.6 years earlier if they had high 10-year risk alone,high lifetime risk alone,or both high 10-year and high lifetime risk at the index age of 35 years,respectively.We developed wellperformed lifetime risk prediction equations that will help to identify those with the greatest potential to avert ASCVD burden after implementation of innovative clinical and public health interventions in China.Fangchao Liu Jianxin Li Jichun Chen Dongsheng Hu Ying Li Jianfeng Huang Xiaoqing Liu Xueli Yang Jie Cao Chong Shen Ling Yu Zhendong Liu Xianping Wu Liancheng Zhao Xigui Wu Dongfeng Gu Xiangfeng Lu 2018Science Bulletin2018,63,12:30
10Modeling net primary productivity of the terrestrial ecosystem in China from 1961 to 2005显示文摘网络主要生产率(NPP ) 是代表生态系统的结构和函数的最重要的索引。NPP 能被动态全球植被模型(DGVM ) 模仿,它被设计相对环境变化代表植被动力学。这研究在气候,土壤,和地形学上与数据基于 DGVM 综合生物圈模拟器(朱鹭) 模仿了瓷器生态系统的 NPP。在瓷器陆上的生态系统的 NPP 模拟的朱鹭的适用性首先被验证。有另外的相关研究的比较显示范围和模拟的吝啬的价值通常在观察的限制以内;全面模式和全部的年度 NPP 接近与另外的模型一起进行的模拟。模拟基于遥感离 NPP 评价也靠近。确认证明那朱鹭能在瓷器自然生态系统在 NPP 的大规模模拟被利用。我们然后从 1961 ~ 2005 与气候变化数据模仿了 NPP,当温暖是特别地惹人注目的时。下列是模拟的结果。(1 ) 全部的 NPP 在过去的 45 年里从 3.61 GtC/yr 变化了到 4.24 GtC/yr 并且展出了最小的重要线性增加或减少。(2 ) 在增加的地区性的差别或在 NPP 的减少大,但是展出了一个不足道的全面线性趋势。NPP 在大多数部分衰退了东方并且华中,特别在黄土高原。(3 ) 类似于年度 NPP 的变化法律,季节的 NPP 也显示了不足道的增加或减少;趋势线在一般水平以内。(4 ) 在季节的 NPP 变化的地区性的差别大。NPP 在黄土高原在春天,夏天,和秋天衰退了,但是在西藏的高原的大多数部分增加了。YUAN Quanzhi WU Shaohong ZHAO Dongsheng DAI Erfu CHEN Li ZHANG Lei 2014Journal of Geographical Sciences2014,24,1:27
11Trends in particulate matter and its chemical compositions in China from 2013–2017显示文摘Accurate determination of the atmospheric particulate matter mass concentration and chemical composition is helpful in exploring the causes and sources of atmospheric enthalpy pollution and in evaluating the rationality of environmental air quality control strategies.Based on the sampling and chemical composition data of PM2.5 in different key regions of China in the CARE-China observation network,this research analyzes the environmental air quality data released by the China National Environmental Monitoring Centre during the studied period to determine the changes in the particulate matter mass concentration in key regions and the evolution of the corresponding chemical compositions during the implementation of the Action Plan for Prevention and Control of Air Pollution from 2013-2017.The results show the following.(1)The particulate matter mass concentration in China showed a significant downward trend;however,the PM2.5 annual mass concentration in 64%of cities exceeds the New Chinese Ambient Air Quality Standard(CAAQS)GradeⅡ(GB3095-2012).The region to the east of the Taihang Mountains,the Fenhe and Weihe River Plain and the Urumqi-Changji regions in Xinjiang,all have PM2.5 concentration loading that is still high,and heavy haze pollution occurred frequently in the autumn and winter.(2)During the heavy pollution in the autumn and winter,the concentrations of sulfate and organic components decreased significantly.The mean SO42-concentration in PM2.5 decreased by 76%,12%,81%and 38%in Beijing-Tianjin-Hebei(BTH),the Pearl River Delta(PRD),the Sichuan-Chongqing region(SC)and the Fenhe and Weihe River Plain,respectively.The mean organic matter(OM)concentration decreased by 70%,44%,48%and 31%,respectively,and the mean concentration of NH4+decreased by 68%,1.6%,38%and 25%,respectively.The mean elemental carbon(EC)concentration decreased by 84%and 20%in BTH and SC,respectively,and it increased by 61%and 11%in the PRD and Fenhe and Weihe River Plain,respectively.The mean concentration of mineral and unresolved chemical components(MI)dropped by 70%,24%and 13%in BTH,the PRD and the Fenhe and Weihe River Plain,respectively.The change in the PM2.5 chemical composition is consistent with the decrease of the PM2.5mass concentration.(3)In 2015,the mean OM concentration contributions to fine particles and coarse particles were 13-46%and 46-57%,respectively,and the mean MI concentration contributions to fine particles and coarse and particles were 31-60%and 39-73%,respectively;these values are lower than the 2013 values from the key regions,which is the most important factor behind the decrease of the particulate matter mass concentration.From 2013 to 2015,among the chemical components of different particle size fractions,the peak value of the coarse particle size fraction decreased significantly,and the fine particle size fractions of SO42-,NO3-,and NH4+decreased with the decrease of the particulate matter mass concentration in different particle size fractions.The fine-particle size peaks of SO42-,NO3-and NH4+shifted from 0.65-1.1μm to the finer size range of0.43-0.65μm during the same time frame.Yuesi WANG Wenjie LI Wenkang GAO Zirui LIU Shili TIAN Rongrong SHEN Dongsheng JI Shuai WANG Lili WANG Guiqian TANG Tao SONG Mengtian CHENG Gehui WANG Zhengyu GONG Jiming HAO Yuanhang ZHANG 2019Science China Earth Sciences2019,62,12:23
12Meteorological mechanism for a large-scale persistent severe ozone pollution event over eastern China in 2017显示文摘An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017.73 out of 96 selected cities,most located in the Beijing-TianjinHebei and the surrounding area(BTHS),suffered severe ozone pollution.A north-south contrast ozone distribution,with higher ozone(199±33μg/m3)in the BTHS and lower ozone(118±25μg/m^3)in the Yangtze River Delta(YRD),was found to be dominated by the position of the West Pacific Subtropical High(WPSH)and mid-high latitude wave activities.In the BTHS,the positive anomalies of geopotential height at 500 hPa and temperature at the surface indicated favorable meteorological conditions for local ozone formation.Prevailing northwesterly winds in the mid-high troposphere and warm advection induced by weak southerly winds in the low troposphere resulted in low-moderate relative humidity(RH),less total cloud cover(TGC),strong solar radiation and high temperatures.Moreover,southerly winds prevailing over the BTHS aggravated the pollution due to regional transportation of O3 and its precursors.On one hand,the deep sinking motion and inversion layer suppressed the dispersion of pollutants.On the other hand,O3-rich air in the upper layer was maintained at night due to temperature inversion,which facilitated O3 vertical transport to the surface in the next-day morning due to elevated convection.Generally,temperature,UV radiation,and RH showed good correlations with O3 in the BTHS,with rates of 8.51(μg/m^3)/℃(within the temperature range of 20-38℃),59.54(μg/m^3)/(MJ/m^2)and-1.93(μg/m^3)/%,respectively.Jia Mao Lili Wang Chuhan Lu Jingda Liu Mingge Li Guiqian Tang Dongsheng Ji Nan Zhang Yuesi Wang 2020Journal of Environmental Sciences2020,32,6:18
13Activity criterion of pre-existing fabrics in non-homogeneous deformation domain显示文摘The Anderson's model can be applied only to elastic homogeneous deformation and cannot explain complicated phenomena of natural faults, which to a large degree limits the model to practical application. By combing the Coulomb-Mohr Criterion with the sandbox modeling and considering non-homogeneous deformation, mechanisms of how basement pre-existing fabrics control fault formation and evolution are analyzed and a mechanical factor, activation-coefficient (faS) of pre-existing fabrics, is proposed. It is determined by the attitude and mechanical properties of pre-existing fabric, and the stress state (the magnitudes and directions of the three principal stresses). The coefficient has taken the heterogeneity of rocks into account and may serve as a criterion for evaluating the activity of a pre-existing fabric. The Mohr-Coulomb Criterion is expanded to non-homogeneous deformation domain in terms of activation-coefficient (faS) of pre-existing fabrics, the general law of the activity of a pre-existing fabric is predicted, the fault complexity real of rift basin is revealed in theory, and the controlling law of basement pre-existing faults to fault formation and evolution is determined, and checked with sandbox modeling. A new way is provided for in-depth study of faulting.TONG HengMao CAI DongSheng WU YongPing LI XiaoGuang LI XuShen MENG LingJian 2010Science China Earth Sciences2010,53,8:17
14Ages of the Laocheng Granitoids and Crustal Growth in the South Qinling Tectonic Domain,Central China:Zircon U-Pb and Lu-Hf Isotopic Constraints显示文摘Laocheng granitoid pluton 位于 Qinling erogenic 带的南方 Qinling 构造领域,南部的 Shaanxi 省,并且由石英闪长岩, granodiorite 和 monzogranite 主要组成。LA-ICP-MS 锆石 U-Pb 与阴极射线发光图象一起,同位素的标明日期表明石英闪长岩和 granodiorite 是从 220 妈的 emplaced 到 216 妈,当 monzogranite 是在 210 妈的 emplaced 时。在原处,锆石 Hf 同位素的分析证明从 8.1 的石英闪长岩和到 +1.3 的 granodiorite 范围的 Hf (t)价值,和单个阶段的 Hf 从 809 妈为年龄建模到 1171 妈,当 monzogranite 的 Hf (t)价值是 14.5 到 +16.7 和单个阶段的 Hf 时,从 189 妈为年龄建模到 1424 妈。这些 Hf 同位素的特征表明石英闪长岩, granodiorite 和 monzogranite 从混合从弄空的披风和更低的大陆的部分融化导出的岩浆被形成外壳的材料,并且在 Neoproterozoic ( 800 妈)和 Indosinian ( 210 妈)期间有大陆人外壳生长的二个阶段分别地,时代在 Qinling orogrnic 的南方 Qinling 构造领域系上带子,华中。YANG Pengtao LIU Shuwen LI Qiugen ZHANG Fan WANG Zongqi WANG Dongsheng WANG Ruiting YAN Quanren YAN Zhen 2011Acta Geologica Sinica(English Edition)2011,85,4:15
15Bioptical microcycles of laminated speleothems from China and their chronological significance显示文摘Interfaces of microlayers, in most stalagmites from China, consist of opaque and organic materials. Observed with microscope, the interfaces seem dark under transmitted light and luminiferous under reflected fluorescent light. Stalagmites in which the two optical characters are unified spatially would be most suitable for cross-dating use, and can play an important role in the study on speleochronology and speleoclimatology.Ming Tan Xiaoguang Qin Linmei Shen Xianfeng Wang Yongjin Wang Tieying Li Linhua Song Laihong Wang Dongsheng Liu 1999Chinese Science Bulletin1999,44,17:14
16Relationship between heavy metals and dissolved organic matter released from sediment by bioturbation/bioirrigation显示文摘Organic matter(OM) is an important component of sediment. Bioturbation/bioirrigation can remobilize OM and heavy metals that were previously buried in the sediment. The remobilization of buried organic matter, thallium(Tl), cadmium(Cd), copper(Cu) and zinc(Zn) from sediment was studied in a laboratory experiment with three organisms: tubificid,chironomid larvae and loach. Results showed that bioturbation/bioirrigation promoted the release of dissolved organic matter(DOM) and dissolved Tl, Cd, Cu and Zn, but only dissolved Zn concentrations decreased with exposure time in overlying water. The presence of organisms altered the compositions of DOM released from sediment,considerably increasing the percentage of fulvic acid-like materials(FA) and humic acidlike materials(HA). In addition, bioturbation/bioirrigation accelerated the growth and reproduction of bacteria to enhance the proportion of soluble microbial byproduct-like materials(SMP). The DOM was divided into five regions in the three-dimensional excitation emission matrix(3 D-EEM), and each part had different correlation with the dissolved heavy metal concentrations. Dissolved Cu had the best correlation with each of the DOM compositions, indicating that Cu in the sediment was in the organic-bound form.Furthermore, the organism type and heavy metal characteristics both played a role in influencing the remobilization of heavy metal.Yi He Bin Men Xiaofang Yang Yaxuan Li Hui Xu Dongsheng Wang 2019Journal of Environmental Sciences2019,31,1:12
17Distribution feature of terrestrial heat flow densities in the Bohai Basin,East China显示文摘Temperature logging curves at 8 boreholes and well-testing temperature data at 142 boreholes are used to determine geotemperature gradients in the Bohai Basin. The thermal conductivities of 86 rock samples are measured at laboratory and the effects of porosity and temperature are corrected to obtain conductivities in situ. Terrestrial heat flow densities at 76 wells are determined based on these data. The distribution of the heat flow indicates that the terrestrial heat flow in the Bohai Basin is relatively high with an average value of 65.8 mW/m2. This characteristic is caused by the tectonic evolution of the basin. During Cenozoic, the litho-sphere stretched intermittently and the crust thinned so that heat conducted from the mantle increased and formed thermal abnormity at depth beneath the basin.WANG Liangshu LIU Shaowen XIAO Weiyong LI Cheng LI Hua GUO Suiping LIU Bo LUO Yuhui CAI Dongsheng 2002Chinese Science Bulletin2002,47,10:10
18Optimal sensor placement in health monitoring of suspension bridge显示文摘Structural health monitoring(SHM) provides an effective approach to ensure the safety of structures.However,with the restriction of the cost of sensor system and data processing,only a small number of sensors could be available in the health monitoring system(HMS).In order to obtain the best identification of structural characteristics,optimal sensor placement(OSP) becomes an inevitable task in the design of HMS.This paper introduces the process for determining the OSP in HMS of a suspension bridge,in which four different OSP methods have been investigated,including the effective independence(EI) method,the effective independence driving-point residue(EFI-DPR) method,the minimized modal assurance criterion(minMAC) method and the principal subset selection-based extended EI(PSS-EI) method.Then,three criteria,which are modal assurance matrix(MAC),condition number(CN) of mode shape matrix and determinant of Fisher information matrix(FIM),were employed to evaluate the effect of the OSP methods respectively.The result showed that the PSS-EI method developed has the ability to guarantee the highest determinant of FIM,a relatively small off-diagonal term of MAC and agreeable CN,as well as the deployment of sensors in a uniform and symmetric fashion for the studied bridge.Finally,the scheme obtained by PSS-EI was adopted in the HMS.LI BinBin LI DongSheng ZHAO XueFeng OU JinPing 2012Science China(Technological Sciences)2012,55,7:9
19Fatigue damage characterization of carbon fiber reinforced polymer bridge cables:Wavelet transform analysis for clustering acoustic emission data显示文摘Carbon fiber reinforced polymer(CFRP)has many remarkable merits.It is lightweight and has great rigidity and high intensity. High-durability cable produced from CFRP as reinforcement material is widely used in bridge construction projects.However, there is a dearth of studies regarding damage types and mechanism under fatigue load of CFRP bridge cables.In this paper,we adopt acoustic emission(AE)technology to monitor fatigue damage and failure of the CFRP bridge cables,specifically by monitoring the bridge cable’s fatigue test process and using wavelet transformation to analyze data.Results show that damage on the CFRP cable is divided into three stages.Based on wavelet singularity theory,in each stage of AE,the burst signal is obtained and its time-frequency distribution is achieved through wavelet analysis.According to the analysis results,failure modes in each phase and type of acoustic emission source are easy to determine.The characteristics of waveform,types of damages, and frequency distribution of CFRP bridge cable in different damage phases are collected.Research shows that the method used to determine the types of fatigue damage on the CFRP cable is feasible according to the range of distribution characteristic parameters for acoustic emission signal and type of waveform.LI DongSheng HU Qian OU JinPing LI Hui 2011Science China(Technological Sciences)2011,54,2:9
20Impending HRT wave precursors to the Wenchuan M_s8.0 earthquake and methods of earthquake impending prediction by using HRT wave显示文摘We deployed four geo-electric monitoring stations in Sichuan and Yunnan provinces from 2004, using the new generation of equipment (PS-100) and technologies to capture the HRT wave earthquake precursor. Before the Wenchuan Ms8.0 earthquake, we recorded the HRT wave precursor at the only operating station in Hongge (HG, Δ=465 km) and found that significant impending signal had been recorded at the station in the early morning ( 0―5 am) of 12th of May, 2008. The precursor for this earthquake is consistent with precursors recorded for other strong earthquakes. The measured physical properties (geo-resistivity and telluric-current) show tidal wave period oscillations from several days to several months before the earthquakes and the amplitude of such HT oscillation increases significantly towards the occurrence of an earthquake. These HT and RT waves from the epicenter have a causal relationship with the earthquakes that happened several days later. The arrival time of two RT waves is proportional to the distance from the station to the epicenter. The estimated natural decay of the amplitude is correlated with the natural period (T0) of the earthquake fault, which is proportional to the fault length. From this relationship, we can predict the earthquake magnitude. For magnitude 6―9 earthquakes, the natural period is about 1―6 hours. Such oscillation comes from the epicenter area and they can propagate several thousand kilometers in the Earth's crust. Before a strong earthquake in the shallow crust, the conductive pore fluid will experience major changes before the fault rapture. Such fluid change will emit an oscillation in the pore fluid pressure. This is the mechanism for the HRT wave generation. Since the China Earthquake Administration funded the HRT wave short-term earth-quake prediction project in 2003, the first record of HRT precursor wave has been recorded from the 2004-12-26 Sumatra Mw9.0 earthquake with the largest epicentre distance Δ=2900 km. Thereafter, we have captured HRT waves from more than twenty strong earthquakes, which are well-matched and show repeatability, consistency and regularity. All our observation with the HRT waves demonstrate that HRT wave precursors to earthquakes indeed exist. Strong earthquakes can be predicted and short-term and impending earthquake prediction is achievable in the very near future. From all the observations, including the ones at HG station from Wenchuan Ms8.0 earthquake, we conclude that using HRT wave to predict earthquakes is feasible.QIAN FuYe ZHAO BiRu QIAN Wei ZHAO Jian HE ShiGen ZHANG HongKui LI ShiYu LI ShaoKun YAN GuLiang WANG ChengMin SUN ZhenKai ZHANG DongNing LU Jun ZHANG Ping YANG GuoJun SUN JiaLin GUO ChunSheng TANG YuXiong XU JianMing XIA KunTao JU Hang YIN BangHong LI Ming YANG DongSheng QI WeiLuo HE TaiMing GUAN HuaPing ZHAO YuLin 2009Science China Earth Sciences2009,52,10:8
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