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A Robust CRISPR/Cas9 System for Convenient, High-Efficiency Multiplex Genome Editing in Monocot and Dicot Plants 被引量:344
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作者 Xingliang Ma Qunyu Zhang +17 位作者 Qinlong Zhu Wei Liu Yan Chen Rong Qiu Bin Wang Zhongfang Yang Heying Li Yuru Lin Yongyao Xie Rongxin Shen Shuifu Chen Zhi Wang Yuanling Chen Jingxin Guo Letian Chen Xiucai Zhao Zhicheng Dong Yao-Guang Liu 《Molecular Plant》 SCIE CAS CSCD 2015年第8期1274-1284,共11页
CRISPR/Cas9 genome targeting systems have been applied to a variety of species. However, most CRISPR/Cas9 systems reported for plants can only modify one or a few target sites. Here, we report a robust CRISPR/Cas9 vec... CRISPR/Cas9 genome targeting systems have been applied to a variety of species. However, most CRISPR/Cas9 systems reported for plants can only modify one or a few target sites. Here, we report a robust CRISPR/Cas9 vector system, utilizing a plant codon optimized Cas9 gene, for convenient and high- efficiency multiplex genome editing in monocot and dicot plants. We designed PCR-based procedures to rapidly generate multiple sgRNA expression cassettes, which can be assembled into the binary CRISPR/ Cas9 vectors in one round of cloning by Golden Gate ligation or Gibson Assembly. With this system, we edi- ted 46 target sites in rice with an average 85.4% rate of mutation, mostly in biallelic and homozygous status. We reasoned that about 16% of the homozygous mutations in rice were generated through the non-homol- ogous end-joining mechanism followed by homologous recombination-based repair. We also obtained uni- form biallelic, heterozygous, homozygous, and chimeric mutations in Arabidopsis T1 plants. The targeted mutations in both rice and Arabidopsis were heritable. We provide examples of loss-of-function gene mu- tations in To rice and T1Arabidopsis plants by simultaneous targeting of multiple (up to eight) members of a gene family, multiple genes in a biosynthetic pathway, or multiple sites in a single gene. This system has provided a versatile toolbox for studying functions of multiple genes and gene families in plants for basic research and genetic improvement. 展开更多
关键词 sequence-specific nucleases genome editing CRISPR/Cas9 rice Arabidopsis
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Active tectonic blocks and strong earthquakes in the continent of China 被引量:262
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作者 ZHANG Peizhen (张培震) DENG Qidong (邓起东) ZHANG Guomin (张国民) MA Jin (马 瑾) GAN Weijun (甘卫军) MIN Wei (闵 伟) MAO Fengying (毛凤英) WANG Qi (王 琪) 《Science China Earth Sciences》 SCIE EI CAS 2003年第z2期13-24,共12页
The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have b... The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have been separated from each other by active tectonic zones. Boundaries between blocks are the highest gradient of differential movement. Most of tectonic activity occurs on boundaries of the blocks. Earthquakes are results of abrupt releases of accumulated strain energy that reaches the threshold of strength of the earth's crust. Boundaries of tectonic blocks are the locations of most discontinuous deformation and highest gradient of stress accumulation, thus are the most likely places for strain energy accumulation and releases, and in turn, devastating earthquakes. Almost all earthquakes of magnitude greater than 8 and 80%-90% of earthquakes of magnitude over 7 occur along boundaries of active tectonic blocks. This fact indicates that differential movements and interactions of active tectonic blocks are the primary mechanism for the occurrences of devastating earthquakes. 展开更多
关键词 active TECTONIC block interactions of blocks differential movement STRONG EARTHQUAKE activity.
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心理韧性研究诸进路 被引量:152
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作者 席居哲 左志宏 WU Wei 《心理科学进展》 CSSCI CSCD 北大核心 2012年第9期1426-1447,共22页
心理韧性研究自发轫至今出现了若干可供遵循的进路,主要有:以人为中心模型、以变量为中心模型、时间路径模型和因素-过程模型等。以人为中心进路围绕"人"开展研究,将甄别出的心理韧性者与非韧性者及未经历严重压力/逆境者进... 心理韧性研究自发轫至今出现了若干可供遵循的进路,主要有:以人为中心模型、以变量为中心模型、时间路径模型和因素-过程模型等。以人为中心进路围绕"人"开展研究,将甄别出的心理韧性者与非韧性者及未经历严重压力/逆境者进行比较,尝试理解心理韧性的由来。以变量为中心进路则聚焦于压力/危险逆境指标、心理韧性相关因子及心理社会发展功能指标,经由分析这些变量的关系以探寻和推测心理韧性发展的机制。时间路径进路专注于时间进程,追踪研究对象在严重压力/逆境开始前后到相当长一段时期心理社会功能变化过程特点,以解读人类压力/逆境适应系统的运作特征及其功能差异,推断心理韧性发展的过程及机制。因素-过程整合进路则以生态系统理论为指导,兼顾因素与过程,尝试提供一个更具研究指导性的心理韧性整合模型和一套机制解释策略基准框架。诸心理韧性研究进路各有侧重,互有长短,研究者对之了然于胸将有助于选择适切的研究设计与分析策略,取长避短,从而提高研究揭示效力。 展开更多
关键词 心理韧性 研究进路 以人为中心模型 以变量为中心模型 时间路径模型 因素-过程整合模型
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Risk assessment of heavy metals in soils and vegetables around nonferrous metals mining and smelting sites,Baiyin,China 被引量:87
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作者 LI Yu WANG Yan-bin +2 位作者 GOU Xin SU Yi-bing WANG Gang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1124-1134,共11页
A field survey was conducted to investigate the metal and arsenic contamination in soils and vegetables on four villages (Shuichuan (SCH), Beiwan (BWA), Dongwan (DWA) and Wufe (WFE)) located along, Baiyin, C... A field survey was conducted to investigate the metal and arsenic contamination in soils and vegetables on four villages (Shuichuan (SCH), Beiwan (BWA), Dongwan (DWA) and Wufe (WFE)) located along, Baiyin, China, and to evaluate the possible health risks to local population through foodchain. Results show that the most significantly contaminated soils occurred upstream at SCH where Cd, Cu and As concentrations exceeded maximum allowable concentrations for Chinese agricultural soil. Further downstream the degree of contamination semi-systematically decreased in concentrations of metal. Generally, the leafy vegetables were more heavily contaminated than non-leafy vegetables. Chinese cabbage is the most severely contaminated, the concentrations of Cd exceeded the maximum permit levels (0.05 mg/kg) by 4.5 times. Bio-accumulate factor also shows that an entry of Cd to food chain plants is the greatest potential. Furthermore, the estimated daily intake amounts of the considered toxic elements (Cd, Pb and Cu) from the vegetables grown at SCH and BWA and DWA have exceeded the recommended dietary allowance levels. Thus, the vegetables grown in three villages above, which affected by Baiyin mining and smelting have a health hazard for human consumption. 展开更多
关键词 vegetable species heavy metals mining and smelting pollution
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Current cancer burden in China: epidemiology, etiology, and prevention 被引量:77
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作者 Maomao Cao He Li +8 位作者 Dianqin Sun Siyi He Xinxin Yan Fan Yang Shaoli Zhang Changfa Xia Lin Lei Ji Peng Wanqing Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第8期1121-1138,共18页
Cancer has become the most common cause of death in China.Owing to rapid economic development,improved livelihood,and shifts in risk factors,cancer epidemiology has experienced substantial changes during the past seve... Cancer has become the most common cause of death in China.Owing to rapid economic development,improved livelihood,and shifts in risk factors,cancer epidemiology has experienced substantial changes during the past several decades.In this review,we aim to describe the current cancer epidemiology of the main types of cancer in China,report major risk factors associated with cancer development,and summarize the contributions of the Chinese government to controlling the cancer burden.A total of 4,064,000 new cases were diagnosed in China in 2016.The most frequent types are lung cancer(828,100;20.4%),colorectal cancer(408,000;10.0%),and gastric cancer(396,500;9.8%).Lung(657,000;27.2%),liver(336,400,13.9%),and stomach(288,500;12.0%)cancers are the 3 most deadly cancers in the general population.The 5-year survival rate for cancer has dramatically increased in recent decades.However,liver and particularly pancreatic cancers still have the poorest prognosis.The main modifiable risk factors associated with cancer development include infectious agents,smoking,alcohol consumption,obesity,unhealthful dietary habits,and inadequate physical activity.The Chinese government has made unremitting efforts to decrease the cancer burden,including cancer education and investment in cancer screening programs. 展开更多
关键词 Cancer burden risk factor PREVENTION China
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Concentration and source identification of polycyclic aromatic hydrocarbons and phthalic acid esters in the surface water of the Yangtze River Delta,China 被引量:56
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作者 Lifei Zhang Liang Dong Lijun Ren Shuangxin Shi Li Zhou Ting Zhang Yeru Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第2期335-342,共8页
The pollution from polycyclic aromatic hydrocarbons(PAHs) and phthalic acid esters(PAEs) in the surface water of the rapidly urbanized Yangtze River Delta region was investigated.Fourteen surface water samples wer... The pollution from polycyclic aromatic hydrocarbons(PAHs) and phthalic acid esters(PAEs) in the surface water of the rapidly urbanized Yangtze River Delta region was investigated.Fourteen surface water samples were collected in June 2010.Water samples were liquid-liquid extracted using methylene chloride and analyzed by gas chromatography-mass spectrometry.Concentrations of PAHs and PAEs ranged 12.9-638.1 ng/L and 61-28550 ng/L,respectively.Fluoranthene,naphthalene,pyrene,phenanthrene,di-2ethylhexyl phthalate,and di-n-butyl phthalate were the most abundant compounds in the samples.The water samples were moderately polluted with benzo[a]pyrene according to China's environmental quality standard for surface water.The two highest concentrations of PAHs and PAEs occurred in samples from Taihu Lake,Wuxi City and the western section of Yangchenghu Lake.Potential sources of pollution at S7 were petroleum combustion and the plastics industry,and at Yangchenghu Lake were petroleum combustion and domestic waste.Pollution in samples from the Beijing-Hangzhou Grand Canal originated from diesel engines.There were no obvious sources of pollution for the other water samples.These results can be used as reference levels for future monitoring programs of pollution from PAHs and PAEs. 展开更多
关键词 polycyclic aromatic hydrocarbons phthalic acid esters Yangtze River Delta surface water
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心理韧性儿童的社会能力自我觉知 被引量:53
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作者 席居哲 左志宏 桑标 《心理学报》 CSSCI CSCD 北大核心 2011年第9期1026-1037,共12页
旨在考察心理韧性儿童与缺乏心理韧性儿童相比社会能力自我觉知特点,以探究社会能力自我觉知的心理韧性发展意蕴。利用量表法和内隐联结测验(IAT),对经由汇聚操作法筛选出的99名心理韧性儿童和176名缺乏心理韧性儿童,分别测量社会能力... 旨在考察心理韧性儿童与缺乏心理韧性儿童相比社会能力自我觉知特点,以探究社会能力自我觉知的心理韧性发展意蕴。利用量表法和内隐联结测验(IAT),对经由汇聚操作法筛选出的99名心理韧性儿童和176名缺乏心理韧性儿童,分别测量社会能力外显自我觉知与内隐自我觉知,并从2个信息源多角度测量其实际社会能力。结果发现:心理韧性儿童比缺乏心理韧性儿童有更高水平的社会能力外显自我觉知,社会能力自我觉知与心理社会发展功能总体上存在极其显著的正向关联;心理韧性组儿童自我觉知的社会能力低于其实际社会能力但两者显著正相关,缺乏心理韧性组儿童自我觉知的社会能力接近于其实际社会能力但两者不存在显著相关,两组儿童自我觉知的社会能力与实际社会能力之差的差异极其显著;心理韧性儿童在内隐社会能力自我觉知测验不相容任务与相容任务上反应时之差显著大于缺乏心理韧性儿童。这提示,外显上谨慎一致的高水平社会能力自我觉知和内隐上更倾向于认为自己有能力或为心理韧性发展的主体性机制原因之一。 展开更多
关键词 社会能力自我觉知 自我效能感 心理韧性儿童 缺乏心理韧性儿童 内隐联结测验
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Identification of serum proteins discriminating colorectal cancer patients and healthy controls using surface-enhanced laser desorption ionisation-time of flight mass spectrometry 被引量:45
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作者 Judith YMN Engwegen Helgi H Helgason +4 位作者 Annemieke Cats Nathan Harris Johannes MG Bonfrer Jan HM Schellens Jos H Beijnen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第10期1536-1544,共9页
AIM: To detect the new serum biomarkers for colorectal cancer (CRC) by serum protein profiling with surfaceenhanced laser desorption ionisation - time of flight mass spectrometry (SELDI-TOF MS). METHODS: Two ind... AIM: To detect the new serum biomarkers for colorectal cancer (CRC) by serum protein profiling with surfaceenhanced laser desorption ionisation - time of flight mass spectrometry (SELDI-TOF MS). METHODS: Two independent serum sample sets were analysed separately with the ProteinChip technology (set A: 40 CRC + 49 healthy controls; set B: 37 CRC + 31 healthy controls), using chips with a weak cation exchange moiety and buffer pH 5. Discriminative power of differentially expressed proteins was assessed with a classification tree algorithm. Sensitivities and specificities of the generated classification trees were obtained by blindly applying data from set A to the generated trees from set B and vice versa. CRC serum protein profiles were also compared with those from breast, ovarian, prostate, and non-small cell lung cancer. RESULTS: Mass-to-charge ratios (m/z) 3.1×10^3, 3.3× 10^3, 4.5×10^3, 6.6×10^3 and 28×10^3 were used as classitiers in the best-performing classification trees. Tree sensitivities and specificities were between 65% and 90%.Host of these discriminative m/z values were also different in the other tumour types investigated. M/z 3.3× 10^3, main classifier in most trees, was a doubly charged form of the 6.6× 10^3-Da protein. The latter was identified as apolipoprotein C-I. M/z 3.1×10^3 was identified as an N-terminal fragment of albumin, and m/z 28× 10^3 as apolipoprotein A-I. CONCLUSION: SELDI-TOF MS followed by classification tree pattern analysis is a suitable technique for finding new serum markers for CRC. Biomarkers can be identified and reproducibly detected in independent sample sets with high sensitivities and specificities. Although not specific for CRC, these biomarkers have a potential role in disease and treatment monitoring. 展开更多
关键词 PROTEOMICS Colorectal cancer BIOMARKER Sensitivity SPECIFICITY
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Spatial-Temporal Pattern and Driving Forces of Land Use Changes in Xiamen 被引量:41
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作者 QUAN Bin CHEN Jian-Fei +4 位作者 QIU Hong-Lie M. J. M. ROMKENS YANG Xiao-Qi JIANG Shi-Feng LI Bi-Cheng 《Pedosphere》 SCIE CAS CSCD 2006年第4期477-488,共12页
Using Landsat TM data of 1988, 1998 and 2001, the dynamic process of the spatial-temporal characteristics of land use changes during 13 years from 1988 to 2001 in the special economic zone of Xiamen, China was analyze... Using Landsat TM data of 1988, 1998 and 2001, the dynamic process of the spatial-temporal characteristics of land use changes during 13 years from 1988 to 2001 in the special economic zone of Xiamen, China was analyzed to improve understanding and to find the driving forces of land use change so that sustainable land utilization could be practiced. During the 13 years cropland decreased remarkably by nearly 11304.95 ha. The areas of rural-urban construction and water body increased by 10 152.24 ha and 848.94 ha, respectively. From 1988 to 2001, 52.5% of the lost cropland was converted into rural-urban industrial land. Rapid urbanization contributed to a great change in the rate of cropland land use during these years. Land-reclamation also contributed to a decrease in water body area as well as marine ecological and environmental destruction. In the study area 1) urbanization and industrialization, 2) infrastructure and agricultural intensification, 3) increased affluence of the farming community, and 4) policy factors have driven the land use changes. Possible sustainable land use measures included construction of a land management system, land planning, development of potential land resources, new technology applications, and marine ecological and environmental protection. 展开更多
关键词 driving force GIS land use change remote sensing XIAMEN
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Tapetum Degeneration Retardation is Critical for Aliphatic Metabolism and Gene Regulation during Rice Pollen Development 被引量:42
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作者 Da-Sheng Zhang Wan-Qi Liang +6 位作者 Zheng Yuan Na Li Jing Shi Jue Wang Yu-Min Liu Wen-Juan Yu Da-Bing Zhang 《Molecular Plant》 SCIE CAS CSCD 北大核心 2008年第4期599-610,共12页
As a complex wall system in flowering plants, the pollen outer wall mainly contains aliphatic sporopollenin; however, the mechanism for synthesizing these lipidic precursors during pollen development remains less well... As a complex wall system in flowering plants, the pollen outer wall mainly contains aliphatic sporopollenin; however, the mechanism for synthesizing these lipidic precursors during pollen development remains less well understood. Here, we report on the function of the rice tapetum-expressing TDR (Tapetum Degeneration Retardation) gene in aliphatic metabolism and its regulatory role during rice pollen development. The observations of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses suggested that pollen wall formation was significantly altered in the tdr mutant. The contents of aliphatic compositions of anther were greatly changed in the tdr mutant revealed by GC-MS (gas chromatography-mass spectrometry) testing, particularly less accumulated in fatty acids, primary alcohols, alkanes and alkenes, and an abnormal increase in secondary alcohols with carbon lengths from C29 to C3S in tdr. Microarray data revealed that a group of genes putatively involved in lipid transport and metabolism were significantly altered in the tdr mutant, indicating the critical role of TDR in the formation of the pollen wall. Also, a wide range of genes (236 in total--154 up-regulated and 82 down-regulated) exhibited statistically significant expressional differences between wild-type and tdr. In addition to its function in promoting tapetum PCD, TDR possibly plays crucial regulatory roles in several basic biological processes during rice pollen development. 展开更多
关键词 TAPETUM pollen wall aliphatic metabolism microarray gene expression RICE
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Focal depth research of earthquakes in China's Mainland: Implication for tectonics 被引量:41
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作者 ZHANG Guomin WANG Suyun +2 位作者 LI Li ZHANG Xiaodong MA Hongsheng 《Chinese Science Bulletin》 SCIE CAS 2002年第12期969-974,1057-1058,共8页
Focal depth data of earthquakes in China's Mainland are processed and analyzed in this paper, as well as the relationship between the focal depths and large-scale tectonic structures. As a basic parameter for eart... Focal depth data of earthquakes in China's Mainland are processed and analyzed in this paper, as well as the relationship between the focal depths and large-scale tectonic structures. As a basic parameter for earthquakes, focal depth is used to investigate deep environment of seis-mogenic regions, tectonic backgrounds for concentration and release of seismic energy, the inner crustal deformation and its mechanic features. Depth data of 31282 ML≥2.0 events with 1st class and 2nd class precision in China's Mainland from Jan. 1, 1970 to May 31, 2000 are used to get spatial features of earthquakes distributed with depth and to provide average depth for each grid area throughout China. Researches show that the average depth (D) for all the earthquakes used in this paper is (16±7) km, and (13±6) km and (18±8) km for the events in eastern China and western China, respectively. The area with the deepest focal depth is located in southwest Xinjiang region, near the western and southwestern ends of the Tarim 展开更多
关键词 MAINLAND China FOCAL depth.
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The Influence of Vegetation Cover on Summer Precipitation in China: a Statistical Analysis of NDVI and Climate Data 被引量:41
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作者 张井勇 董文杰 +1 位作者 符淙斌 吴凌云 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第6期1002-1006,共5页
This study provides new evidence for the feedback effects of vegetation cover on summer precipitation in different regions of China by calculating immediate (same season), and one-and two-season lagged correlations be... This study provides new evidence for the feedback effects of vegetation cover on summer precipitation in different regions of China by calculating immediate (same season), and one-and two-season lagged correlations between the normalized difference vegetation index (NDVI) and summer precipitation. The results show that the correlation coefficients between NDVI in spring and the previous winter and precipitation in summer are positive in most regions of China, and they show significant difference between regions. The stronger one-and two-season lagged correlations occur in the eastern arid/semi-arid region, Central China, and Southwest China out of the eight climatic regions of China, and this implies that vegetation cover change has more sensitive feedback effects on summer precipitation in the three regions. The three regions are defined as sensitive regions. Spatial analyses of correlations between spring NDVI averaged over each sensitive region and summer precipitation of 160 stations suggest that the vegetation cover strongly affects summer precipitation not only over the sensitive region itself but also over other regions, especially the downstream region. 展开更多
关键词 INFLUENCE vegetation cover summer precipitation
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中国高分辨率温度和降水模拟数据的验证 被引量:36
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作者 朱华忠 罗天祥 Christopher Daly 《地理研究》 CSCD 北大核心 2003年第3期349-359,共11页
PRISM模型是一种基于地理特征和回归统计方法生成气候图的模型。基于中国及其周边国家地区 2 4 5 0多个气象台站观测数据 ,以PRISM模型模拟生成了中国 2 5′× 2 5′ (≈ 4~5km)逐月温度和降水数据。利用独立于模拟数据的中国生... PRISM模型是一种基于地理特征和回归统计方法生成气候图的模型。基于中国及其周边国家地区 2 4 5 0多个气象台站观测数据 ,以PRISM模型模拟生成了中国 2 5′× 2 5′ (≈ 4~5km)逐月温度和降水数据。利用独立于模拟数据的中国生态系统研究网络 18个野外观测站的长年气候观测数据 ,检验了PRISM模型的模拟结果 ,表明PRISM模型较好地模拟了我国温度和降水的空间分布及季节变化 ,除了在高山和亚热带地区由于地表覆盖和局部地形的差异影响模拟结果 ,其模拟值与实测值之间的趋势线同 1∶1线基本一致 ,具有显著相关关系 。 展开更多
关键词 平均最高气温 平均最低气温 降水 PRISM模型 CERN生态站
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不同分布距离的软弱夹层对洞室稳定性的影响研究 被引量:38
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作者 张志强 李宁 +1 位作者 陈方方 G.Swoboda 《岩土力学》 EI CAS CSCD 北大核心 2007年第7期1363-1368,共6页
软弱夹层等不良结构面对地下洞室的围岩稳定与支护结构安全起着决定性的作用,本文研究了顶部分布有软弱夹层隧洞的围岩稳定性与支护结构安全性,重点研究了夹层分布距离分别为0.2B,0.5B,1.0B(B为洞跨)3种情况,总结了夹层分布距离与洞周... 软弱夹层等不良结构面对地下洞室的围岩稳定与支护结构安全起着决定性的作用,本文研究了顶部分布有软弱夹层隧洞的围岩稳定性与支护结构安全性,重点研究了夹层分布距离分别为0.2B,0.5B,1.0B(B为洞跨)3种情况,总结了夹层分布距离与洞周关键点位移、围岩应力、围岩塑性区的关系,分析了不同的分布距离下喷层的受力状况,并进一步探讨了常见围岩类型(II类、III类、IV类)中不同分布距离的软弱夹层对地下洞室围岩稳定性的影响,得出了不同分布距离软弱夹层对围岩变形、应力、支护结构受力影响的一些量化成果。研究成果可望对地下洞室选线(址)、支护系统优化以及施工有借鉴意义与指导作用。 展开更多
关键词 软弱夹层 分布距离 地下洞室 围岩稳定性 数值试验
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Sulfur-doped g-C3N4/TiO2 S-scheme heterojunction photocatalyst for Congo Red photodegradation 被引量:40
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作者 Juan Wang Guohong Wang +2 位作者 Bei Cheng Jiaguo Yu Jiajie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期56-68,共13页
Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-sc... Constructing step-scheme(S-scheme)heterojunctions has been confirmed as a promising strategy for enhancing the photocatalytic activity of composite materials.In this work,a series of sulfur-doped g-C3N4(SCN)/TiO2 S-scheme photocatalysts were synthesized using electrospinning and calcination methods.The as-prepared SCN/TiO2 composites showed superior photocatalytic performance than pure TiO2 and SCN in the photocatalytic degradation of Congo Red(CR)aqueous solution.The significant enhancement in photocatalytic activity benefited not only from the 1D well-distributed nanostructure,but also from the S-scheme heterojunction.Furthermore,the XPS analyses and DFT calculations demonstrated that electrons were transferred from SCN to TiO2 across the interface of the SCN/TiO2 composites.The built-in electric field,band edge bending,and Coulomb interaction synergistically facilitated the recombination of relatively useless electrons and holes in hybrid when the interface was irradiated by simulated solar light.Therefore,the remaining electrons and holes with higher reducibility and oxidizability endowed the composite with supreme redox ability.These results were adequately verified by radical trapping experiments,ESR tests,and in situ XPS analyses,suggesting that the electron immigration in the photocatalyst followed the S-scheme heterojunction mechanism.This work can enrich our knowledge of the design and fabrication of novel S-scheme heterojunction photocatalysts and provide a promising strategy for solving environmental pollution in the future. 展开更多
关键词 TiO2 nanofiber Sulfur-doped g-C3N4 Step-scheme heterojunction photocatalysis In situ XPS S-scheme mechanism
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Analysis of pesticide residues in commercially available chenpi using a modified QuEChERS method and GC-MS/MS determination 被引量:39
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作者 Shuang Li Peipei Yu +4 位作者 Ceng Zhou Ling Tong Dongxiang Li Zhiguo Yu Yunli Zhao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第1期60-69,共10页
To ensure the safety of the commercially available chenpi,a convenient and fast analytical method was developed for the determination of 133 pesticide residues in chenpi using gas chromatography-tandem mass spectromet... To ensure the safety of the commercially available chenpi,a convenient and fast analytical method was developed for the determination of 133 pesticide residues in chenpi using gas chromatography-tandem mass spectrometry(GC-MS/MS).In this study,different extraction solvents,redissolution solvents and adsorbents were tested according to the recovery and purification effect to obtain a modified QuEChERS method.The samples were extracted with acetonitrile.During the clean-up step,octadecyl-modified silica(C18)and graphitized carbon black(GCB)were selected,and aminopropyl(NH2)was used instead of primary secondary amine(PSA)because of its weaker ion exchange capacity which had little effect on the recovery of ditalimfos.Samples were quantified by matrix-matched calibration with internal standards.All pesticides showed good linearity in the respective range,both with values of r2>0.99.The average recoveries of the pesticides spiked samples ranged from 70.0% to 112.2% with the RSDs of 0.2%–14.4%.The modified QuEChERS method was validated and applied to twenty real samples.Five pesticides were found in eight batches,but no pesticide exceeded the maximum residue limits(MRL,MRL reference to European commission). 展开更多
关键词 Pesticide residues Chenpi GC-MS/MS QUECHERS
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Regional Tectonic Transformation in East Kunlun Orogenic Belt in Early Paleozoic: Constraints from the Geochronology and Geochemistry of Helegangnaren Alkali-feldspar Granite 被引量:38
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作者 LI Ruibao PEI Xianzhi +6 位作者 LI Zhuochen SUN Yu PEI Lei CHEN Guochao CHEN Youxin LIU Chengjun WEI Fanghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第2期333-345,共13页
The Helegangnaren feldspar granite exposed in the eastern part of East Kunlun, is characterized by high concentrations of SiO2 and alkaline, low abundances of Fe, Mg and Ca, metaluminous-weak peraluminous. Trace eleme... The Helegangnaren feldspar granite exposed in the eastern part of East Kunlun, is characterized by high concentrations of SiO2 and alkaline, low abundances of Fe, Mg and Ca, metaluminous-weak peraluminous. Trace elements analysis shows that the granite is depleted extremely in Ba, Sr and Eu, and rich in some large-ion lithophile elements and high field strength elements. Besides, the granite has high Ga contents, the values of 104(Ga/AI) vary from 2.50 to 2.77, which is mainly greater than the lower limit of A-type granites (2.6), and is higher than the I- and S- type granites' average (2.1 and 2.28, respectively). Rare earth element (REE) is characterized by relatively high fractionations of light REE (LREE) and heavy REE (HREE) (LREE/HREE=9.3-13.60, (La/Yb)N=10.92-18.02), pronounced negative Eu anomalies (JEn=0.08-0.13), and exhibits right- dipping gull pattern. Major elements, rare elements and trace elements features show the granite is ascribed to A-type granite and A2 subtype in tectonic genetic type. They are plotted into post-collision or within-plate area in a variety of tectonic discriminations. Geological and geochemical data comprehensively suggest that the granite is formed in a post-collision extensive tectonic setting. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating yields a weighted mean age of 425 Ma, belonging to Middle Silurian, which is similar to the age of the post- collision geological events in the region. The differences of magmatic rocks in formation age, rocks assemblage and rocks series systematically indicate that the regional tectonic stress regime in the East Kunlun orogenic belt experienced a major transformation from compress to extension in Middle Silurianin, and the Helegangnaren feldspar granite intruded in the early stage of tectonic transformation. 展开更多
关键词 A-type granite post orogeny compound orogeny East Kunlun
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Spatial Characteristics of Extreme Rainfall over China with Hourly through 24-Hour Accumulation Periods Based on National-Level Hourly Rain Gauge Data 被引量:38
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作者 Yongguang ZHENG Ming XUE +2 位作者 Bo LI Jiong CHEN Zuyu TAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第11期1218-1232,共15页
Hourly rainfall measurements of 1919 national-level meteorological stations from 1981 through 2012 are used to document,for the first time,the climatology of extreme rainfall in hourly through 24-h accumulation period... Hourly rainfall measurements of 1919 national-level meteorological stations from 1981 through 2012 are used to document,for the first time,the climatology of extreme rainfall in hourly through 24-h accumulation periods in China. Rainfall amounts for 3-,6-,12- and 24-h periods at each station are constructed through running accumulation from hourly rainfall data that have been screened by proper quality control procedures. For each station and for each accumulation period,the historical maximum is found,and the corresponding 50-year return values are estimated using generalized extreme value theory. Based on the percentiles of the two types of extreme rainfall values among all the stations,standard thresholds separating Grade I,Grade II and Grade III extreme rainfall are established,which roughly correspond to the 70th and 90th percentiles for each of the accumulation periods. The spatial characteristics of the two types of extreme rainfall are then examined for different accumulation periods. The spatial distributions of extreme rainfall in hourly through 6-h periods are more similar than those of 12- and 24-h periods. Grade III rainfall is mostly found over South China,the western Sichuan Basin,along the southern and eastern coastlines,and in the large river basins and plains. There are similar numbers of stations with Grade III extreme hourly rainfall north and south of 30°N,but the percentage increases to about 70% south of 30°N as the accumulation period increases to 24 hours,reflecting richer moisture and more prolonged rain events in southern China. Potential applications of the extreme rainfall climatology and classification standards are suggested at the end. 展开更多
关键词 extreme rainfall meteorological historical moisture eastern north coastal monsoon seasonal
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风暴尺度天气下利用集合卡尔曼滤波模拟多普勒雷达资料同化试验Ⅰ. 不考虑模式误差的情形 被引量:36
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作者 兰伟仁 朱江 +2 位作者 Ming XUE Jidong GAO 雷霆 《大气科学》 CSCD 北大核心 2010年第3期640-652,共13页
本文在假定模式无偏差的情况下,利用一次风暴过程的模拟多普勒雷达资料进行一系列风暴天气尺度的集合卡尔曼滤波资料同化试验,检验集合卡尔曼滤波在风暴天气尺度资料同化方面的效果,并验证各集合卡尔曼滤波参数对同化效果的影响。试验... 本文在假定模式无偏差的情况下,利用一次风暴过程的模拟多普勒雷达资料进行一系列风暴天气尺度的集合卡尔曼滤波资料同化试验,检验集合卡尔曼滤波在风暴天气尺度资料同化方面的效果,并验证各集合卡尔曼滤波参数对同化效果的影响。试验结果表明,集合卡尔曼滤波能有效地应用于风暴尺度的资料同化;40个集合成员以及6km的局地化尺度能较好地滤除采样误差造成的虚假相关,同时可以将观测信息传递到无观测的模式格点;利用背景场加上空间平滑的高斯型随机扰动生成初始成员的方式较未经过平滑的方式有更好的分析效果;背景场扰动方法能够提高样本的离散度;只同化反射率的同化试验表明,反射率的同化效果较明显,也证明了集合卡尔曼滤波在非常规资料同化中的作用;增加径向风资料同化的效果优于只进行反射率同化的结果。 展开更多
关键词 风暴尺度 模拟多普勒雷达资料 集合卡尔曼滤波 敏感性试验
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Chinmedomics: A Powerful Approach Integrating Metabolomics with Serum Pharmacochemistry to Evaluate the Efficacy of Traditional Chinese Medicine 被引量:36
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作者 Ai-Hua Zhang Hui Sun +3 位作者 Guang-Li Yan Ying Han Qi-Qi Zhao Xi-Jun Wang 《Engineering》 SCIE EI 2019年第1期60-68,共9页
Evaluation of the efficacy of traditional Chinese medicines (TCMs) is an important prerequisite for discovering effective substances, lead compounds, and quality markers (Q markers). At present, there is an urgent nee... Evaluation of the efficacy of traditional Chinese medicines (TCMs) is an important prerequisite for discovering effective substances, lead compounds, and quality markers (Q markers). At present, there is an urgent need to develop a biological language that can act as abridge for the scientific elaboration of the efficacy of TCMs, and to further highlight the significant value of TCM. Chinese medicinal syndromes and formulae are two essential parts of TCM that directly relate to its efficacy. Syndromes and formulae have been taken as the research objects. The serum pharmacochemistry of the TCM approach with metabolomics were integrated to establish an innovative chinmedomics strategy, which is able to explore syndrome biomarkers and evaluate TCM efficacy in order to discover effective substances from TCMs. A great deal of concrete work in chinmedomics has already performed to bridge the gap between Chinese and Western medicine, and to provide a powerful approach to enhance the scientific value of TCM theory and clinical practice. This article summarizes the application of chinmedomics in identifying the candidate biomarkers of a syndrome and revealing the efficacy of the related formula. We also highlight the discovery of lead compounds and Q markers from TCMs. 展开更多
关键词 Chinmedomics SERUM pharmacochemistry of TCM EFFICACY Metabolomics SYNDROME Biomarkers Quality MARKERS
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