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1A Diagnostic Study of the Impact of El Nion on the Precipitation in China显示文摘1.IntroductionEINifioisthemostoutstandinginterannualvariabilityintheocean.Itiswellknownthattheheatsourcedrivingtheatmosphericgeneralcirculationismainlywithinthetropics.EINinooccursinthetropicalPacificandthewarmingoftheoceanduringtheEINinocancoveralar...张人禾 1999Advances in Atmospheric Sciences1999,16,2:86
2Climatology and Interannual Variability of the Southeast Asian Summer Monsoon显示文摘ClimatologyandInterannualVariabilityoftheSoutheastAsianSummerMonsoonK.-M.LauLaboratoryforAtmospheres,Code913,NASA-GoddardSpac...K. M. Lau Song Yang 1997Advances in Atmospheric Sciences1997,14,2:123
3The amalgamation of the supercontinent of North China Craton at the end of Neo-Archaean and its breakup during late Palaeoproterozoic and Meso-Proterozoic显示文摘The most important geological events in the formation and evolution of the North China Craton concentrate at two stages: 2 600-2 400 Ma and 2 000-1 700 Ma (briefly, we call them 2.5 Ga event and 1.8 Ga event respectively in this paper). We propose that the essences of these two events are: Several Archaean micro-continents amalgamated to form one supercontinent according to the plate tectonic principle with a small scale at about 2.5 Ga, and the supercontinent broke down by upwelling of an ancient mantle plume at about 1.8 Ga.翟明国 卞爱国 赵太平 2000Science China Earth Sciences2000,43,S1:162
4Liver cancer incidence and mortality in China: Temporal trends and projections to 2030显示文摘Objective: Liver cancer is one of the most common cancers and major cause of cancer deaths in China,which accounts for over 50% of new cases and deaths worldwide.The systematic liver cancer statistics including of projection through 2030 could provide valuable information for prevention and control strategies in China,and experience for other countries.Methods: The burden of liver cancer in China in 2014 was estimated using 339 cancer registries' data selected from Chinese National Cancer Center(NCC).Incident cases of 22 cancer registries were applied for temporal trends from 2000 to 2014.The burden of liver cancer through 2030 was projected using age-period-cohort model.Results: About 364,800 new cases of liver cancer(268,900 males and 95,900 females) occurred in China,and about 318,800 liver cancer deaths(233,500 males and 85,300 females) in 2014.Western regions of China had the highest incidence and mortality rates.Incidence and mortality rates decreased by about 2.3% and 2.6% per year during the period of 2000-2014,respectively,and would decrease by more than 44% between 2014 and 2030 in China.The young generation,particularly for those aged under 40 years,showed a faster down trend.Conclusions: Based on the analysis,incidence and mortality rates of liver cancer are expected to decrease through 2030,but the burden of liver cancer is still serious in China,especially in rural and western areas.Most cases of liver cancer in China can be prevented through vaccination and more prevention efforts should be focused on high risk groups.Rongshou Zheng Chunfeng Qu Siwei Zhang Hongmei Zeng Kexin Sun Xiuying Gu Changfa Xia Zhixun Yang He Li Wenqiang Wei Wanqing Chen Jie He 2018Chinese Journal of Cancer Research2018,30,6:132
5The updated incidences and mortalities of major cancers in China, 2011显示文摘Introduction: The National Central Cancer Registry(NCCR) of China collected population-based cancer registration data from all cancer registries in China. This study aimed to compile national cancer incidences and mortalities in 2011 and estimate cancer incident new cases and cancer deaths.Methods: In 2014, there were 234 cancer registries that submitted records of new cancer cases and cancer deaths that occurred in 2011 to the NCCR. All datasets were evaluated based on the criteria of data quality of the NCCR. The data of 177 registries was of suicient quality and was compiled to evaluate cancer statistics in 2011. The pooled data were stratiied by area, sex, age group, and cancer type. Cancer incident cases and deaths were estimated using age-standardized rates(ASR) and the Chinese population. All incidences and mortalities were age-standardized to the 2000 Chinese standard population and Segi's population.Results: The estimates of new cancer incident cases and cancer deaths were 3,372,175 and 2,113,048 in 2011, respectively. The crude incidence was 250.28/1,00,000(277.77/1,00,000 for males and 221.37/1,00,000 for females). The ASRs of incidence by the Chinese standard population(ASRIC) and by the world standard population(ASRIW) were 186.34/1,00,000 and 182.76/1,00,000, respectively, with a cumulative incidence(0–74 years old) of 21.20%. Cancers of the lung, female breast, stomach, liver, colorectum, esophagus, cervix, uterus, prostate, and ovary were the most common cancers, accounting for approximately 75% of all new cancer cases. Lung, liver, gastric, esophageal, colorectal, female breast, pancreatic, brain, and cervical cancers and leukemia were the leading causes of cancer death, accounting for approximately 80% of all cancer deaths. Cancer incidence, mortality, and spectrum were all diferent between urban and rural areas and between males and females.Conclusions: The population covered by the cancer registries greatly increased from 2010 to 2011. The data quality and representativeness of cancer registries have gradually improved. Cancer registries have an irreplaceable role in research on cancer prevention and control. The disease burden of cancer is increasing, and the health department must implement efective measures to contain the increased cancer burden in China.Wanqing Chen Rongshou Zheng Hongmei Zeng Siwei Zhang 2015Chinese Journal of Cancer2015,34,11:113
61990—2015年中国四类慢性病早死概率与"健康中国2030"下降目标分析显示文摘目的 分析1990—2015年中国全国及各省份心脑血管疾病、肿瘤、糖尿病和慢性呼吸系统疾病等四类慢性病早死概率、变化趋势,以及实现"健康中国2030"重大慢性病早死概率下降目标的情况.方法 利用2015年全球疾病负担研究结果 ,根据WHO推荐的早死概率计算方法,计算、分析和比较1990—2015年中国全国及各省份(不包括中国台湾数据)不同性别四类慢性病早死概率及其年均变化速度;并以"健康中国2030"重大慢性病早死概率目标——下降30%为标准,评价各省四类慢性病早死概率实现目标的难度.结果1990—2015年中国男性和女性心脑血管疾病、肿瘤和慢性呼吸系统疾病早死概率均呈持续下降的趋势,四类慢性病合计的早死概率由30.69%降至18.54%,女性的下降速度(由25.97%降至12.40%)远快于男性(由34.94%降至24.19%).2015年四类慢性病早死概率较高的前5位省份依次为青海(28.81%)、西藏(25.88%)、贵州(24.67%)、广西(23.56%)和新疆(23.21%),而较低的前5位依次为上海(8.40%)、北京(9.39%)、香港特别行政区(10.10%)、澳门特别行政区(10.31%)和浙江(11.70%);如果实现"健康中国2030"目标,2030年早死概率较高的两个省份青海和西藏应分别下降至20.17%和18.12%,而上海和北京则应分别下降至5.88%和6.57%.1990—2015年中国四类慢性病早死概率的年均下降速度为2.00%,下降速度较快的前5个省份依次是北京(3.48%)、上海(3.24%)、浙江(2.81%)、福建(2.75%)和广东(2.67%),且包括这5个省份在内的11个省份按既往下降速度均能实现"健康中国2030"目标,而其他22个省份则无法实现控制目标,需要更大的下降速度才能达标.结论 1990—2015年中国全国及各省份四类慢性病早死概率呈持续下降趋势,与女性相比,男性的早死概率较高且下降速度较慢,各省份的四类慢性病早死概率及其变化速度存在着较大差异,根据1990—2015年的数据,约有2/3的省份与实现"健康中国2030"的目标尚有相当距离.曾新颖 李镒冲 刘世炜 王黎君 刘韫宁 刘江美 周脉耕 2017中华预防医学杂志2017,51,3:181
7Anthropogenic emission inventories in China:a review显示文摘The development of reliable anthropogenic emission inventories is essential for both understanding the sources of air pollution and designing effective air-pollution-control measures in China. However, it is challenging to quantify emissions in China accurately, given the variety of contributing sources, the complexity of the technology mix and the lack of reliable measurements. Over the last two decades,tremendous efforts have been made to improve the accuracy of emission inventories, and significant improvements have been realized. More reliable statistics and survey-based data have been used to reduce the uncertainties in activity rates and technology distributions. Local emission factors and source profiles covering various sources have been measured and reported. Based on these local databases, improved emission inventory models have been developed for power plants, large industrial plants and the residential,transportation and agricultural sectors. In this paper, we review the progress that has been made in developing inventories of anthropogenic emissions in China. We first highlight the major updates that have been made to emission inventory models and the underlying data by source category. We then summarize the sector-based estimates of emissions of different species contained in current inventories. The progress that has been made in the development of model-ready emissions is also presented. Finally, we suggest future directions for further improving the accuracy of emission inventories in China.Meng Li Huan Liu Guannan Geng Chaopeng Hong Fei Liu Yu Song Dan Tong Bo Zheng Hongyang Cui Hanyang Man Qiang Zhang Kebin He 2017National Science Review2017,4,6:100
8Estimates of cancer incidence and mortality in China,2013显示文摘Introduction: Population-based cancer registration data are collected by the National Central Cancer Registry in China every year. Cancer incident cases and cancer deaths in 2013 were analyzed.Methods: Through the procedure of quality control, reported data from 255 registries were accepted to establish the national database for cancer estimates. Incidences and mortalities were calculated with stratification by area(urban/rural), sex(male/female), age group(0,1-4,5-9,10-14... 80-84, and 85-year-old and above), and cancer site.The structure of Segi's population was used for the calculation of age-standardized rates(ASR).Top 10 most common cancers and leading causes of cancer deaths were listed.Results: In 2013,3,682,200 new cancer cases and 2,229,300 cancer deaths were estimated in China based on the pooled data from 255 cancer registries, covering 16.65% of the national population. The incidence was270.59/100,000, with an ASR of 186.15/100,000; the mortality was 166.83/100,000, with an ASR of 108.94/100,000.The top 10 most common cancer sites were the lung, stomach, liver, colorectum, female breast, esophagus, thyroid, cervix, brain, and pancreas. The ten leading causes of cancer deaths were lung cancer, liver cancer, gastric cancer, esophageal cancer, colorectal cancer, pancreatic cancer, female breast cancer, brain tumor, leukemia, and lymphoma.Conclusions: Cancer leaves serious disease burden in China with high incidence and mortality. Lung cancer was the most common cancer and the leading cause of cancer death in China. Efficient control strategy is needed, especially for major cancers.Rongshou Zheng Hongmei Zeng Siwei Zhang Wanqing Chen 2017Chinese Journal of Cancer2017,36,8:84
9培育世界一流科技期刊的机遇、挑战与对策研究显示文摘中央深化改革委员会第五次会议审议通过《关于深化改革培育世界一流科技期刊的意见》一年多来,中国科学技术协会联合相关部门对标中央要求,合力协同推进,联手打出系列组合拳,受到国内外科技界、期刊界广泛关注.对科技期刊怎么看、怎么办,已成为科技界的大课题、大事件.何为世界一流科技期刊、为什么要培育世界一流期刊、如何有效推进期刊建设等问题,也在各界引起广泛讨论.笔者在此分享一些个人的思考.张昕 王素 刘兴平 2020科学通报2020,65,9:82
10Prevalence of Autism Spectrum Disorder in China:A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years显示文摘This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling.The Modified Chinese Autism Spectrum Rating Scale was used for the screening process.Of the target population of 142,086 children,88.5%(n=125,806) participated in the study.A total of 363 children were confirmed as having ASD.The observed ASD prevalence rate was 0.29%(95% CI:0.26%-0.32%) for the overall population.After adjustment for response rates,the estimated number of ASD cases was867 in the target population sample,thereby achieving an estimated prevalence of 0.70%(95% CI:0.64%-0.74%).The prevalence was significantly higher in boys than in girls(0.95%;95% CI:0.87%-1.02% versus 0.30%;95%CI:0.26%-0.34%;P <0.001).Of the 363 confirmed ASD cases,43.3% were newly diagnosed,and most of those(90.4%) were attending regular schools,and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity.Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children.Hao Zhou Xiu Xu Weili Yan Xiaobing Zou Lijie Wu Xuerong Luo Tingyu Li Yi Huang Hongyan Guan Xiang Chen Meng Mao Kun Xia Lan Zhang Erzhen Li Xiaoling Ge Lili Zhang Chunpei Li Xudong Zhang Yuanfeng Zhou Ding Ding Andy Shih Eric Fombonne Yi Zheng Jisheng Han Zhongsheng Sun Yong-hui Jiang Yi Wang LATENT-NHC Study Team 2020Neuroscience Bulletin2020,36,9:158
11Changing profiles of cancer burden worldwide and in China: a secondary analysis of the global cancer statistics 2020显示文摘Background:Cancer is one of the leading causes of death globally,but its burden is not uniform.GLOBOCAN 2020 has newly updated the estimates of cancer burden.This study summarizes the most recent changing profiles of cancer burden worldwide and in China and compares the cancer data of China with those of other regions.Methods:We conducted a descriptive secondary analysis of the GLOBOCAN 2020 data.To depict the changing global profile of the leading cancer types in 2020 compared with 2018,we extracted the numbers of cases and deaths in 2018 from GLOBOCAN 2018.We also obtained cancer incidence and mortality from the 2015 National Cancer Registry Report in China when sorting the leading cancer types by new cases and deaths.For the leading cancer types according to sex in China,we summarized the estimated numbers of incidence and mortality,and calculated China’s percentage of the global new cases and deaths.Results:Breast cancer displaced lung cancer to become the most leading diagnosed cancer worldwide in 2020.Lung,liver,stomach,breast,and colon cancers were the top five leading causes of cancer-related death,among which liver cancer changed from the third-highest cancer mortality in 2018 to the second-highest in 2020.China accounted for 24%of newly diagnosed cases and 30%of the cancer-related deaths worldwide in 2020.Among the 185 countries included in the database,China’s age-standardized incidence rate(204.8 per 100,000)ranked 65th and the age-standardized mortality rate(129.4 per 100,000)ranked 13th.The two rates were above the global average.Lung cancer remained the most common cancer type and the leading cause of cancer death in China.However,breast cancer became the most frequent cancer type among women if the incidence was stratified by sex.Incidences of colorectal cancer and breast cancer increased rapidly.The leading causes of cancer death varied minimally in ranking from 2015 to 2020 in China.Gastrointestinal cancers,including stomach,colorectal,liver,and esophageal cancers,contributed to a massive burden of cancer for both sexes.Conclusions:The burden of breast cancer is increasing globally.China is undergoing cancer transition with an increasing burden of lung cancer,gastrointestinal cancer,and breast cancers.The mortality rate of cancer in China is high.Comprehensive strategies are urgently needed to target China’s changing profiles of the cancer burden.Wei Cao Hong-Da Chen Yi-Wen Yu Ni Li Wan-Qing Chen 2021Chinese Medical Journal2021,,7:982
12Current cancer situation in China:good or bad news from the 2018 Global Cancer Statistics?显示文摘Cancer is the leading cause of death in China and depicting the cancer pattern of China would provide basic knowhows on how to tackle it more effectively.In this study we have reviewed several reports of cancer burden,including the Global cancer statistics 2018 and Cancer statistics in China,2015,along with the GLOBCAN 2018 online database,to investigate the differences of cancer patterns between China,the United States(USA)and the United Kingdom(UK).An estimated 4.3 million new cancer cases and 2.9 million new cancer deaths occurred in China in 2018.Compared to the USA and UK,China has lower cancer incidence but a 30%and 40%higher cancer mortality than the UK and USA,among which 36.4%of the cancer-related deaths were from the digestive tract cancers(stomach,liver,and esophagus cancer)and have relatively poorer prognoses.In comparison,the digestive cancer deaths only took up≤5%of the total cancer deaths in either USA or UK.Other reasons for the higher mortality in China may be the low rate of early-stage cancers at diagnosis and non-uniformed clinical cancer treatment strategies performed by different regions.China is undergoing the cancer transition stage where the cancer spectrum is changing from developing country to developed country,with a rapidly increase cancer burden of colorectal,prostate,female breast cancers in addition to a high occurrence of infection-related and digestive cancers.The incidence of westernized lifestyle-related cancers in China(i.e.colorectal cancer,prostate,bladder cancer)has risen but the incidence of the digestive cancers has decreased from 2000 to 2011.An estimated 40%of the risk factors can be attributed to environmental and lifestyle factors either in China or other developed countries.Tobacco smoking is the single most important carcinogenic risk factor in China,contributing to~24.5%of cancers in males.Chronic infection is another important preventable cancer contributor which is responsible for~17%of cancers.Comprehensive prevention and control strategies in China should include effective tobacco-control policy,recommendations for healthier lifestyles,along with enlarg-ing the coverage of effective screening,educating,and vaccination programs to better sensitize greater awareness control to the general public.Rui-Mei Feng Yi-Nan Zong Su-Mei Cao Rui-Hua Xu 2019Cancer Communications2019,39,1:675
13Cancer burden of major cancers in China:A need for sustainable actions显示文摘Cancer is still a major health problem in China although numerous efforts have been made for its prevention and control.Findings from this study showed that lung cancer remains the most common type of cancer diagnosed,and was attributed to nearly 30%of all cancer-related deaths.The incidence of the five most common cancers,in China,in 2015,including cancers of the lungs,stomach,colorectum,liver and breast,accounted for almost 60%of all cancers diagnosed.The high cancer burden in China highlights the need for further improvement in health education,professional training and the building up an anti-cancer network for introducing and implementing sustainable actions for cancer control.Maomao Cao He Li Dianqin Sun Wanqing Chen 2020Cancer Communications2020,40,5:140
14Cancer incidence,mortality,and burden in China:a time-trend analysis and comparison with the United States and United Kingdom based on the global epidemiological data released in 2020显示文摘Background:Cancer is one of the leading causes of death and a main economic burden in China.Investigating the differences in cancer patterns and control strategies between China and developed countries could provide reference for policy planning and contribute to improving cancer control measures.In this study,we reviewed the rates and trends of cancer incidence and mortality and disability-adjusted life year(DALY)burden in China,and compared them with those in the United States(US)and the United Kingdom(UK).Methods:Cancer incidence,mortality,and DALY data for China,US and UK were obtained fromtheGLOBOCAN2020 online database,Global Burden of Disease(GBD)2019 study,and Cancer Incidence in Five Continents plus database(CI5 plus).Trends of cancer incidence and mortality in China,US,and UK were analyzed using Joinpoint regression models to calculate annual percent changes(APCs)and identify the best-fitting joinpoints.Results:An estimated 4,568,754 newly diagnosed cancer cases and 3,002,899 cancer deaths occurred in China in 2020.Additionally,cancers resulted in 67,340,309 DALYs in China.Compared to the US and UK,China had lower cancer incidence but higher cancer mortality andDALY rates.Furthermore,the cancer spectrum of China was changing,with a rapid increase incidence and burden of lung,breast,colorectal,and prostate cancer in addition to a high incidence and heavy burden of liver,stomach,esophageal,and cervical cancer.Conclusions:The cancer spectrum of China is changing from a developing country to a developed country.Population aging and increase of unhealthy lifestyles would continue to increase the cancer burden of China.Therefore,the Chinese authorities should adjust the national cancer control program with reference to the practices of cancer control which have been well-established in the developed countries,and taking consideration of the diversity of cancer types by of different regions in China at the same time.Haibo Qiu Sumei Cao Ruihua Xu 2021Cancer Communications2021,41,10:194
15Cancer statistics in China and United States,2022:profiles,trends,and determinants显示文摘Background:The cancer burden in the United States of America(USA)has decreased gradually.However,China is experiencing a transition in its cancer profiles,with greater incidence of cancers that were previously more common in the USA.This study compared the latest cancer profiles,trends,and determinants between China and USA.Methods:This was a comparative study using open-source data.Cancer cases and deaths in 2022 were calculated using cancer estimates from GLOBOCAN 2020 and population estimates from the United Nations.Trends in cancer incidence and mortality rates in the USA used data from the Surveillance,Epidemiology,and End Results program and National Center for Health Statistics.Chinese data were obtained from cancer registry reports.Data from the Global Burden of Disease 2019 and a decomposition method were used to express cancer deaths as the product of four determinant factors.Results:In 2022,there will be approximately 4,820,000 and 2,370,000 new cancer cases,and 3,210,000 and 640,000 cancer deaths in China and the USA,respectively.The most common cancers are lung cancer in China and breast cancer in the USA,and lung cancer is the leading cause of cancer death in both.Age-standardized incidence and mortality rates for lung cancer and colorectal cancer in the USA have decreased significantly recently,but rates of liver cancer have increased slightly.Rates of stomach,liver,and esophageal cancer decreased gradually in China,but rates have increased for colorectal cancer in the whole population,prostate cancer in men,and other seven cancer types in women.Increases in adult population size and population aging were major determinants for incremental cancer deaths,and case-fatality rates contributed to reduced cancer deaths in both countries.Conclusions:The decreasing cancer burden in liver,stomach,and esophagus,and increasing burden in lung,colorectum,breast,and prostate,mean that cancer profiles in China and the USA are converging.Population aging is a growing determinant of incremental cancer burden.Progress in cancer prevention and care in the USA,and measures to actively respond to population aging,may help China to reduce the cancer burden.Changfa Xia Xuesi Dong He Li Maomao Cao Dianqin Sun Siyi He Fan Yang Xinxin Yan Shaoli Zhang Ni Li Wanqing Chen 2022Chinese Medical Journal2022,,5:827
16Major tectonic units of the North China Craton and their Paleoproterozoic assembly显示文摘The basement of the North China Craton can be divided into the Eastern and Western Blocks and the Central Zone (Trans-North China Orogen). The West Block formed by the amal-gamation of the Ordos Block in the south and the Yinshan Block in the north 1.9—2.0 Ga ago. In 1.8—1.9 Ga, the Eastern and Western Blocks were amalgamated along the Central Zone to form the North China Craton.赵国春 孙敏 SimonA.Wilde 2003Science China Earth Sciences2003,46,1:64
17Prevalence of minimal hepatic encephalopathy and quality of life evaluations in hospitalized cirrhotic patients in China显示文摘AIM:To investigate the prevalence of minimal hepatic encephalopathy(MHE)and to assess corresponding health-related quality of life(HRQoL)in hospitalized cirrhotic patients in China.METHODS:This multi-center cross-sectional study included 16 teaching hospitals,which were members of 'Hepatobiliary Cooperation Group,Society of Gastroenterology,Chinese Medical Association',from different areas of China carried out between June and October in 2011.All the eligible hospitalized cirrhotic patients(n = 538)were required to complete triplicate number connection tests combined with one digit symbol test for diagnosing MHE.Patients' clinical examination data were complemented by a modified questionnaire assessing HRQoL.Written informed consent was obtained from each patient.RESULTS:Male was predominant(68.6%)in 519 patients who met the criteria of the study,with a mean age of 49.17 ± 11.02 years.The most common cause of liver cirrhosis was chronic hepatitis B(55.9%).The prevalence of MHE was 39.9% and varied by ChildPugh-Classification score(CPC-A:24.8%,CPC-B:39.4% and CPC-C:56.1%,P < 0.01).MHE(P < 0.01)and higher CPC scores(P < 0.01)were associated with a high HRQoL scores(reflecting poorer quality of life).The prevalence of MHE was proportionate to CPC(P = 0.01)and high quality of life scores(P = 0.01).CONCLUSION:Hospitalized cirrhotic patients have a high prevalence of MHE that is proportionate to the degree of liver function and HRQoL impairment.Ji-Yao Wang Ning-Ping Zhang Bao-Rong Chi Yu-Qing Mi Li-Na Meng Ying-Di Liu Jiang-Bin Wang Hai-Xing Jiang Jin-Hui Yang Yun Xu Xiao Li Jian-Ming Xu Guo Zhang Xin-Min Zhou Yu-Zheng Zhuge De-An Tian Jin Ye Yu-Lan Liu 2013World Journal of Gastroenterology2013,19,30:64
18中亚-蒙古造山带东段的锡林郭勒杂岩:早华力西期造山作用的产物而非古老陆块?——锆石SHRIMP U-Pb年代学证据显示文摘锡林郭勒杂岩是华北板块北缘古生代褶皱带内出露面积最大的变质岩系,以前多被当着前寒武纪的古老地块。本文通过对该杂岩中副片麻岩和正片麻岩的锆石SHRIMP U-Pb年代学研究发现,副片麻岩中的锆石多为岩浆锆石,其^(206)Pb/^(238)U加权平均年龄为406±7Ma,指示它们的原岩主要是由近同期(略早些)的岩浆岩风化后就近沉积的产物,该年龄应代表源区(岛弧型?)花岗岩的形成时间,同时也是副片麻岩原岩沉积的下限年龄。正片麻岩中岩浆锆石的^(206)Pb/^(238)U加权平均年龄为382±2Ma,代表花岗片麻岩原岩的侵位年龄。岩石中锆石的变质增生边的形成年龄为337±6Ma,代表锡林郭勒杂岩发生变质和变形的时间,该变质事件可能与贺根山缝合带内所发生的一次主要的碰撞造山作用有关。这些年龄资料充分说明,锡林郭勒杂岩并非古老地块,而是华力西早期岩浆作用、沉积作用和变质作用事件的产物.整个事件是在较短的时间范围内(~70Ma)完成的,推测该杂岩发育在碰撞造山带的弧前环境。中亚-蒙古造山带东南部(内蒙古的中、东部)碰撞前的构造格局可能不是典型的多岛洋体制,由于缺少古老的陆块,造山过程更多的表现为大洋的大陆化过程,即洋内俯冲形成岛弧,岛弧在被动大陆边缘拼贴聚合转化为新的大陆。薛怀民 郭利军 侯增谦 周喜文 童英 潘晓菲 2009岩石学报2009,25,8:63
19中国区域物流业与经济发展协调度研究--基于复合系统模型与30个省区面板数据显示文摘采用复合系统模型计算了全国30个省(区)物流业子系统与经济子系统的有序度,在此基础上得出了全国与东、中、西3个地区各子系统有序度和复合系统协调度,并进一步分析了经济最发达的4个区域的协调度在研究时段内的变化情况。结果显示对物流业子系统贡献最大的序参量是周转量,受各个地方政府2005年加大物流业投入影响,物流业固定资产投资对物流业子系统贡献也明显上升。对经济子系统而言,城镇与农村居民恩格尔系数与人均工资先后对经济子系统贡献最大。总体上,东、中、西3个地区协调度呈上升趋势。张毅 陈圻 2010软科学2010,24,12:68
20Fluxes of CO_2, N_2O and CH_4 from a typical temperate grassland in Inner Mongolia and its daily variation显示文摘Using a dark enclosed chamber technique, the fluxes of CO2, N2O and CH4 from nature and disturbed grassland were measured on the spot in Inner Mongolian Temperate Grassland along the annual rainfall gradient section ranging from 450 to 200 mm. The results showed that the measured mean fluxes of CO2, N2O and CH4were (1 180.4 ±308.7), (0.010 ± 0.004) and (-0.039 ± 0.016) mg · m-2/h, respectively. The decrease of the fluxes of CO2, N2O and CH4 follows with that of annual rainfall gradient in the measurement area. Human activities, such as grazing and reclamation are also critical factors to affect the fluxes of these gases from grassland. Daily continuous measurement of CO2, N2O and CH4 fluxes showed a strong diurnal variation with higher emission in the daytime. A good relationship between the fluxes of CO2, N2O, CH4 and temperature was exposed in this study.DONG Yunshe, ZHANG Shen, Ql Yuchun, CHEN Zuozhong & GENG Yuanbo1. Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China:2, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Correspondence should be addressed to Dong Yunshe 2000Chinese Science Bulletin2000,45,17:66
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