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138篇 您的检索式:作者名="Wang Jijun"
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1Evidence of crustal ‘channel flow’ in the eastern margin of Tibetan Plateau from MT measurements显示文摘Magnetotelluric (MT) survey has been carried out in the eastern margin of the Tibetan Plateau and its neighboring Shimian-Leshan area, Sichuan Province. Analysis of this MT data reveals that the electric structure of the Tibetan Plateau differ much from that of the Sichuan block. In general, the electric re-sistivity of crust beneath the Sichuan block in the east is larger than that of the eastern margin of the Tibetan Plateau in the west. The crust of the plateau is divided into upper, middle, and lower layers. The middle crust is a low resistivity layer with minimum down to 3―10 Ωm about 10―15 km thick. It pre-sumably contains partial melt and/or salt-bearing fluids with low viscosity, prone to deform and flow, producing a 'channel flow' under the southeastward squeeze of the eastern Tibetan Plateau. This low-resistivity layer makes the upper crust decoupled mechanically from the lower crust. In the brittle upper crust, faults are dominated by left-lateral strike-slip and thrust motions, leading to surface rising and shallow earthquakes. The low-resistivity layer also cut the Xianshuihe-Anninghe fault zone into two sections vertically. In this region, the thicknesses of upper, middle, and lower crust vary laterally, pro-ducing a transitional zone in the eastern margin of the Tibetan Plateau characterized by thicker crust and higher elevation in the west and thinner crust and lower elevation in the east.ZHAO GuoZe CHEN XiaoBin WANG LiFeng WANG JiJun TANG Ji WAN ZhanSheng ZHANG JiHong ZHAN Yan XIAO QiBin 2008Chinese Science Bulletin2008,53,12:57
2Deep structure beneath the southwestern section of the Longmenshan fault zone and seimogenetic context of the 4.20 Lushan M_S7.0 earthquake显示文摘Magnetotelluric measurements were carried out along two profiles across the middle and southwestern sections of the Longmenshan fault zone(LMSf)from 2009 to 2011,after the 2008 Wenchuan MW7.9 earthquake.The former profile crosses the Wenchuan event epicenter and the latter one crosses 2013 Lushan MS7.0 event epicenter.The data were analyzed using advanced processing techniques,including phase tensor and two-dimensional inversion methods,in order to obtain reliable 2-D profiles of the electrical structure in the vicinity of the two earthquakes.A comparison of the two profiles indicates both similarities and differences in the deep crustal structure of the LMSf.West of the southwestern section,a crustal high conductivity layer(HCL)is present at about 10 km depth below the Songpan-Garzêblock;this is about 10 km shallower than that under the middle section of the LMSf.A high resistivity body(HRB)is observed beneath the southwestern section,extending from the near surface to the top of upper mantle.It has a smaller size than the HRB observed below the middle section.In the middle section,there is a local area of decreased resistivity within the HRB but there is absence of this area.The 2013 Lushan earthquake occurred close to the eastern boundary of HRB and the Shuangshi-Dachuan fault,of which the seismogenic context has both common and different features in comparison with the 2008 Wenchuan event.On a large scale,the 2013 Lushan earthquake is associated with the HCL and deformation in the crust including HCL of the eastern Tibetan Plateau.In order to assess seismic risk,it is important to consider both the stress state and the detailed crustal structure in different parts of the LMSf.ZHAN Yan ZHAO GuoZe UNSWORTH Martyn WANG LiFeng CHEN XiaoBin LI Tao XIAO QiBin WANG JiJun TANG Ji CAI JunTao WANG YanZhao 2013Chinese Science Bulletin2013,58,28:39
3Reprogramming of ovine adult fibroblasts to pluripotency via drug-inducible expression of defined factors显示文摘在 enucleated 鸡蛋的体的房间的 Reprogramming 做了多丽,绵羊,在 1996 的第一个成功地克隆的哺乳动物。然而,绵羊的机制体的房间 reprogramming 还没被探讨了。而且,绵羊胚胎的茎(ES ) 细胞仍然不是可得到的,它限制精确修改基因的绵羊的产生。在这研究,我们报导体的房间能是的那只绵羊直接 reprogrammed 到导致的 pluripotent 用定义因素(Oct4, Sox2, c-Myc, Klf4, Nanog, Lin28, SV40 大 T 和 hTERT ) 的茎(iPS ) 房间。我们的观察显示从绵羊的体的细胞比从另外的种,在 iPS,细胞被报导了的体的细胞对改编更困难。我们证明绵羊 iPS 房间表示 ES 房间标记,包括碱的磷酸酶, Oct4, Nanog, Sox2, Rex1,阶段特定的胚胎的 antigen-1, TRA-1-60, TRA-1-81 和 E-cadherin。绵羊 iPS 房间展出了正常 karyotypes 并且能在 vitro 并且在 teratomas 区分进所有三细菌层。我们的学习可以帮助在绵羊揭示体的房间 reprogramming 的机制并且提供一个平台为绵羊 ES 房间探索文化条件。而且,绵羊 iPS 房间可以直接被用来产生精确修改基因的绵羊。Lei Bao Lixiazi He Jijun Chen Zhao Wu Jing Liao Lmgdun Rao Jiangtao Ren Hui Li Hui Zhu Lei Qian Yijun Gu Huimin Dai Xun Xu Jinqiu Zhou Wen Wang Chun Cui Lei Xiao 2011Cell Research2011,21,4:32
4Using aripiprazole to reduce antipsychotic-induced hyperprolactinemia: meta-analysis of currently available randomized controlled trials显示文摘Meiling MENG Wei LI Shaowei ZHANG Hongyan WANG Jianhua SHENG Jijun WANG Chunbo LI 2015上海精神医学2015,27,1:22
5A Strigolactone Biosynthesis Gene Contributed to the Green Revolution in Rice显示文摘Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes.Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture.However,whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive.Here,we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene,HIGH TILLERING AND DWARF 1/DWARF17(HTD1/D17),which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7(CCD7),increases tiller number and improves grain yield in rice.We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1(SD1),both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s.Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.Yuexing Wang Lianguang Shang Hong Yu Longjun Zeng Jiang Hu Shen Ni Yuchun Rao Sanfeng Li Jinfang Chu Xiangbing Meng Lei Wang Ping Hu Jijun Yan Shujing Kang Minghao Qu Hai Lin Tao Wang Quan Wang Xingming Hu Hongqi Chen Bing Wang Zhenyu Gao Longbiao Guo Dali Zeng Xudong Zhu Guosheng Xiong Jiayang Li Qian Qian 2020Molecular Plant2020,13,6:23
6Relation between electricity structure of the crust and deformation of crustal blocks on the northeastern margin of Qinghai-Tibet Plateau显示文摘Study on the electricity structure along a magnetotelluric (MT) sounding profile on the northeastern margin of Qinghai-Tibet Plateau indicates that four crustal blocks can be de-termined from southwest to northeast, namely Bayan Har block (BH), Qin-Qi block (QQ), Hai-yuan block (HY) or the North-South seismotectonic belt and Ordos block (OD). The BH, QQ and OD blocks display a similar electricity structure of the crust. The upper crust represents a high- resistivity layer and the upper part of lower crust represents a low-resistivity layer with the resis-tivity increasing gradually with depth from the lower part of lower crust to the upper mantle. The electricity structure of the crust in these three blocks is similar to that in the complete blocks on the southern and eastern margins of the Qinghai-Tibet Plateau and belongs to normal electricity layering of the crust in slightly deformed or complete intracontinental blocks. The crust in HY block as a boundary zone has been significantly deformed, hence its electricity layering was de-stroyed and the structure was complex and the block became a recent tectonically active and great seismo-active region. The contact belts between the blocks on the northeastern margin of Qinghai-Tibet Plateau exhibit both upthrusting outward and strike-slip movement different from those on the southern and eastern margins of the plateau. The genesis of the low-resistivity layer in the crust is analyzed and the thickness of the lithosphere is estimated in the paper.ZHAO Guoze TANG Ji ZHAN Yan CHEN Xiaobin ZHUO Xianjun WANG Jijun XUAN Fei DENG Qianhui ZHAO Junmeng 2005Science China Earth Sciences2005,48,10:20
7Characterization of drug responses of mini patient-derived xenografts in mice for predicting cancer patient clinical therapeutic response显示文摘Background:Patient-derived organoids and xenografts(PDXs)have emerged as powerful models in functional diag-nostics with high predictive power for anticancer drug response.However,limitations such as engraftment failure and time-consuming for establishing and expanding PDX models followed by testing drug efficacy,and inability to subject to systemic drug administration for ex vivo organoid culture hinder realistic and fast decision-making in selecting the right therapeutics in the clinic.The present study aimed to develop an advanced PDX model,namely MiniPDX,for rapidly testing drug efficacy to strengthen its value in personalized cancer treatment.Methods:We developed a rapid in vivo drug sensitivity assay,OncoVee®MiniPDX,for screening clinically relevant regimens for cancer.In this model,patient-derived tumor cells were arrayed within hollow fiber capsules,implanted subcutaneously into mice and cultured for 7 days.The cellular activity morphology and pharmacokinetics were systematically evaluated.MiniPDX performance(sensitivity,specificity,positive and negative predictive values)was examined using PDX as the reference.Drug responses were examined by tumor cell growth inhibition rate and tumor growth inhibition rate in PDX models and MiniPDX assays respectively.The results from MiniPDX were also used to evaluate its predictive power for clinical outcomes.Results:Morphological and histopathological features of tumor cells within the MiniPDX capsules matched those both in PDX models and in original tumors.Drug responses in the PDX tumor graft assays correlated well with those in the corresponding MiniPDX assays using 26 PDX models generated from patients,including 14 gastric cancer,10 lung cancer and 2 pancreatic cancer.The positive predictive value of MiniPDX was 92%,and the negative predictive value was 81%with a sensitivity of 80%and a specificity of 93%.Through expanding to clinical tumor samples,Min-iPDX assay showed potential of wide clinical application.Conclusions:Fast in vivo MiniPDX assay based on capsule implantation was developed-to assess drug responses of both PDX tumor grafts and clinical cancer specimens.The high correlation between drug responses of paired MiniPDX and PDX tumor graft assay,as well as translational data suggest that MiniPDX assay is an advanced tool for personalized cancer treatment.Feifei Zhang Wenjie Wang Yuan Long Hui Liu Jijun Cheng Lin Guo Rongyu Li Chao Meng Shan Yu Qingchuan Zhao Shun Lu Lili Wang Haitao Wang Danyi Wen 2018Cancer Communications2018,38,1:20
8Updated Review on the Clinical Use of Repetitive Transcranial Magnetic Stimulation in Psychiatric Disorders显示文摘With the ability to modulate cortical activity,repetitive transcranial magnetic stimulation(r TMS) is becoming increasingly important in clinical applications for psychiatric disorders. Previous studies have demonstrated its promising efficacy in depression and schizophrenia, and emerging evidence has also been found in patients with anxiety disorder, obsessive–compulsive disorder, and substance or food craving. However, the overall literature features some conflicting results, varied quality of studies,and a lack of consensus on optimal r TMS parameters.Besides, the efficacy of r TMS in patients with medicationresistant symptoms has drawn most attention from clinicians. Here we review multi-site studies and double-blind randomized controlled trials(RCTs) in single sites, as well as meta-analyses of RCTs in the last three years, in order to update evidence on efficacy and the optimal protocol of r TMS in psychiatric disorders, especially for medicationresistant symptoms.Qian Guo Chunbo Li Jijun Wang 2017Neuroscience Bulletin2017,33,6:17
9Electromagnetic anomaly before earthquakes measured by electromagnetic experiments显示文摘Three experiments are carried out for earthquake monitoring using electromagnetic (EM) methods in recent years. Some earthquakes occurred in chance of the measurement time period for each experiment and the anomalies were recorded before the shocks. The observation at a site 20 km away from the epicenter of Zhangbei MS6.2 earthquake in 1998 shows that the apparent resistivity decreases in the strike direction before and/or during the earthquake and the resistivity increases in the de-cline direction. This anomalous variation in apparent resistivity accounts for about 20%. The apparent resistivities at a site in the epicentral area decrease in the strike and decline directions before and/or during the earthquake and increase after shocks. The experiments using artificial electromagnetic signals with super low frequency carried out in 1999 show that the resolution and stability of electric and magnetic spectra are improved. The spectra of electric and magnetic fields and apparent resistivity at the Baodi station began to anomalously change two days before the Qian'an earthquake with 120 km distant to the station. The anomalous variation of electric and magnetic spectra is about twice as great as normal variation and the apparent resistivity changes by about 20%. The measurements in active seismic area of Yunnan province in the year 2005 indicate that the electric and magnetic spectra anomalously change by one order before the Taoyuan earthquake about 100 km away from the observa-tories. But the measurements at the sites in Beijing area 2 000 km away from the epicenter do not show any anomaly.Guoze Zhao Yan Zhan Lifeng Wang Jijun Wang Ji Tang Qibin Xiao Xiaobin Chen 2009Earthquake Science2009,22,4:16
10Meta-analysis of cognitive function in Chinese first-episode schizophrenia: MATRICS Consensus Cognitive Battery (MCCB) profile of impairment显示文摘Background Compromised neurocognition is a core feature of schizophrenia. With increasing studies researching cognitive function of Chinese patients with first-episode schizophrenia (FES) using MATRICS Consensus Cognitive Battery (MCCB), it is not clear about the level and pattern of cognitive impairment among this population. Aim To provide a meta-analysis systematically analysing studies of neurocognitive function using MCCB in Chinese patients with FES. Methods An independent literature search of both Chinese and English databases up to 13 March 2019 was conducted by two reviewers. Standardised mean difference (SMD) was calculated using the random effects model to evaluate the effect size. Results 56 studies (FES=3167, healthy controls (HC)=3017) were included and analysed. No study was rated as 'high quality' according to Strengthening the Reporting of Observational Studies in Epidemiology. Compared with HCs, Chinese patients with FES showed impairment with large effect size in overall cognition (SMD=-1.60,95% Cl -1.82 to -1.38,厂=67%) and all seven cognitive domains, with the SMD ranging from -0.87 to -1.41. In nine MCCB subtests, patients with FES showed significant difference in Symbol Coding (SMD=-1.90), Trail Making Test (TMT)(SMD=-1.36), Continuous Performance Test-Identical Pairs (SMD=-1.33), Hopkins Verbal Learning Test (SMD=-1.24), Brief Visuospatial Memory Test (SMD=-1.18), Mazes (SMD=-1.16), Category Fluency (SMD=-1.01), Spatial Span (SMD=-0.69) and Mayer-Salovey-Caruso Emotional Intelligence Test (SMD=-0.38). Conclusions Our meta-analysis demonstrates that Chinese patients with FES show neurocognitive deficits across all seven MCCB cognitive domains and all nine subtests, particularly in two neurocognitive domains: speed of processing and attention/vigilance, with the least impairment shown in social cognition. Symbol Coding and TMT may be the most sensitive tests to detect cognitive deficit in Chinese patients with FES.Huijuan Zhang Yao Wang Yuliang Hu Yikang Zhu Tian hong Zhang Jijun Wang Ke Ma Chuan Shi Xin Yu Chunbo Li 2019General Psychiatry2019,32,3:13
11Highly efficient induction and long-term maintenance of multipotent cardiovascular progenitors from human pluripotent stem cells under defined conditions显示文摘心血管的祖先房间( CVPC )源于人的 pluripotent 干细胞( hPSCs ),包括人的胚胎的干细胞( hESCs )和人的导致的 pluripotent 干细胞( hiPSCs ),为心血管的开发和心疾病的基于房间的治疗的学习的抓住伟人诺言,但是他们的应用被困难在他们的有效产生和稳定的维护质问。这研究试图由关键早发展的小径在人的心血管的说明和 CVPC 自强包含了的 modulating 为柔韧的产生和导出 hPSC 的 CVPC 的稳定的繁殖开发化学上定义的系统。此处,我们报导那骨头的联合形态基因的蛋白质 4 (BMP4 ) ,肝糖 synthase kinase 3 (GSK3 ) 禁止者 CHIR99021 和维生素酸是足够的很快变换单层有教养的 hPSCs 包括 hESCs 和 hiPSCs,调节进在在喂免费、没有浆液的文化下面的化学上定义的媒介的同类的 CVPC。在喂免费、没有浆液的条件下面稳定地自我更新、在 10 7-fold 上膨胀的这些 CVPC 从 BMP, GSK3 和 Activin/Nodal 小径的导致区别的信号是什么时候,同时消除了。而且,这些 CVPC 在 vitro 展出了 CVPC,包括 cardiomyocytes 产生主要的心血管的系的保留的潜力,光滑的肌肉房间和 endothelial 房间的期望的染色体宽的分子的特征,并且是在 vivo 的 non-tumorigenic。总的来说,这里报导的确定的系统允许有效产生和导出 hPSC 的 CVPC 的稳定的维护,它代表一个强大的工具学习早胚胎的心血管的开发并且为心肌的再生药提供房间的潜在地安全的来源。Nan Cao He Liang Jijun Huang Jia Wang Yixiong Chen Zhongyan Chen Huang-Tian Yang 2013Cell Research2013,23,9:12
12Piglets cloned from induced pluripotent stem cells显示文摘Nana Fan Jijun Chen Zhouchun Shang Hongwei Dou Guangzhen Ji Qingjian Zou Lu Wu Lixiazi He Fang Wang Kai Liu Na Liu Jianyong Han Qi Zhou Dengke Pan Dongshan Yang Bentian Zhao Zhen Ouyang Zhaoming Liu Yu Zhao Lin Lin Chongming Zhong Quanlei Wang Shouqi Wang Ying Xu Jing Luan Yu Liang Zhenzhen Yang Jing Li Chunxia Lu Gabor Vajta Ziyi Li Hongsheng Ouyang Huayan Wang Yong Wang Yang Yang Zhonghua Liu Hong Wei Zhidong Luan Miguel A Esteban Hongkui Deng Huanming Yang Duanqing Pei Ning Li Gang Pei Lin Liu Yutao Du Lei Xiao Liangxue Lai 2013Cell Research2013,23,1:12
13ζ-Carotene Isomerase Suppresses Tillering in Rice through the Coordinated Biosynthesis of Strigolactone and Abscisic Acid显示文摘Rice tillering is an important agronomic trait affecting grain yield.Here,we identified a high-tillering mutant tillering20(t20),which could be restored to the wild type by treatment with the strigolactone(SL)analog rac-GR24.T20 encodes a chloroplast ζ-carotene isomerase(Z-ISO),which is involved in the biosynthesis of ca-rotenoids and their metabolites,SL and abscisic acid(ABA).The t20 mutant has reduced SL and ABA,raising the question of how SL and ABA biosynthesis is coordinated,and whether they have overlapping functions in tillering.We discovered that rac-GR24 stimulated T20 expression and enhanced all-trans-p-carotene biosynthesis.Importantly,rac-GR24 also stimulated expression of Oryza sativa 9-CIS-EPOXY-CAROTENOID DIOXYGENASE 1(OsNCED1)through induction of Oryza sativa HOMEOBOX12(0sHOX12),promoting ABA biosynthesis in shoot base.On the other hand,ABA treatment significantly repressed SL biosynthesis and the ABA biosynthetic mutants displayed elevated SL biosynthesis.ABA treatment reduced the number of basal tillers in both t20 and wild-type plants.Furthermore,while ABA-deficient mu-tants aba1 and aba2 had the same number of basal tillers as wild type,they had more unproductive upper tillers at maturity.This work demonstrates complex interactions in the biosynthesis of carotenoid,SLs and ABA,and reveals a role for ABA in the regulation of rice tillering.Xue Liu Qingliang Hu Jijun Yan Kai Sun Yan Liang Meiru Jia Xiangbing Meng Shuang Fang Yiqin Wang Yanhui Jing Guifu Liu Dianxing Wu Chengcai Chu Steven M.Smith Jinfang Chu Yonghong Wang Jiayang Li Bing Wang 2020Molecular Plant2020,13,12:11
14Reservoir Characteristics of Lacustrine Shale and Marine Shale:Examples from the Songliao Basin,Bohai Bay Basin and Qiannan Depression显示文摘Lacustrine shale from the Qingshankou Formatin of Songliao basin and the Shahejie Formation of Bohai Bay basin, and marine shale from the lower Cambrian Jiumenchong Formation of Qiannan depression were analysed by using rock pyrolysis, TOC(total organic carbon), XRD(X-ray diffraction), SEM(scanning electron microscope), FE-SEM(field emission scanning electron microscope), high pressure mercury intrusion, and low pressure N_2 and CO_2 gas adsorption experiments, in aim to reveal their reservoir features. The results show that:(1) the width of micro-pores of all the studied samples mainly ranges from 0.45 to 0.7 nm indicated by CO_2 isotherms, and the width of meso-pores is less than 10 nm, with type IV adsorption isotherms and type H2 hysteresis loop, indicative of 'ink-bottle'-shaped pores. Good correlations exist among pore volume, surface area and averaged pore diameter, and a good positive correlation exists between micro-pore volume and TOC content; however, there is no obvious correlation between meso-pore volume and TOC content;(2) interparticle pores, pores among the edge of mineral grains and organic matter pores were all identified in marine and lacustrine shale, among which the interparticle pores may be influence by dissolution effect. Not all bitumen develops organic matter pore, and only high to over mature bitumen present pores. Now the description methods of micrometer scale pores developed in shale are very lack. Microfractures developed in Jiyang depression and dissolution interparticle pores developed in Songliao Basin should be the accumulation sites for shale oil in lacustrine shale, and can be as sweet spots.WANG Min LU Shuangfang WANG Zhiwei LIU Yang HUANG Wenbiao CHEN Fangwen XU Xingyou LI Zheng LI Jijun 2016Acta Geologica Sinica(English Edition)2016,90,3:10
15Terrace dating as an archive of the run-through of the Sanmen Gorges显示文摘Analysis of morphological properties in the Sanmen Gorges region of the Yellow River shows that four river terraces have been developed at the entrance to the gorges. Commonly, thick aeolian loess-paleosol sequence was deposited on the terraces, which makes it easy to date the terraces. The dating of paleomagnetic, loess-paleosol sequence matching and thermoluminescence show that terraces T2, T3 and T4 were formed 0. 129 Ma, 0. 625 Ma and 0. 865 Ma ago, respectively. The formation of these terraces in this region indicates that the Yellow River has experienced four intensive downcutting events during the last 0.9 Ma. The Yellow River cut through the Sanmen Gorges and inpoured into the East China Sea no later than 0. 865 Ma.PAN Baotian WANG Junping GAO Hongshan CHEN Yingying LI Jijun LIU Xiaofeng 2005Progress in Natural Science:Materials International2005,15,12:9
16Concentration level and geographical distribution of nitrobenzene in Chinese surface waters显示文摘Nitrobenzene was reported to occur at relatively high concentrations in some Chinese surface water and to cause an environmental pollution event in 2005.To map the distribution of nitrobenzene in the Chinese surface water throughout China,surface water samples were collected from over 600 sites in the 7 major watersheds and three drainage areas.The samples were analyzed for concentration of nitrobenzene.Overall,nitrobenzene was more frequently detected at higher concentrations in the rivers of North Chin...Jijun, Gao Linghua, Liu Xiaoru, Liu Huaidong, Zhou Zijian, Wang Shengbiao, Huang 2008Journal of Environmental Sciences2008,20,7:9
17Responses of desertification to variations in wind activity over the past five decades in arid and semiarid areas in China显示文摘There have been significant variations in wind activity over the past five decades in arid and semiarid areas in China.High wind activity occurred from the 1960s to the 1970s,but wind activity has de-creased continuously from the 1980s to the present;as a result,the potential sand transport during the latter period was only 20%-50% of the values during the 1960s and 1970s.Phases of high wind activ-ity were highly consistent with the trends in desertification over the past five decades in arid and semiarid areas in China,but spring precipitation was also a significant factor:rapid desertification during the 1960s and 1970s was due to high wind activity,generally combining with low spring pre-cipitation;subsequent rehabilitation since the 1980s has resulted from the combined effects of low wind activity and higher spring precipitation.Therefore,although modern desertification and rehabili-tation processes are being more or less affected by human activities,both processes appear to be more strongly controlled by climate change.WANG XunMing LI JiJun DONG GuangRong XIA DunSheng 2008Chinese Science Bulletin2008,53,3:9
18Identification of the lower limit of high-quality source rocks and its relation to hydrocarbon accumulation——Taking the Beier Sag in the Hailaer Basin as an example显示文摘The theory of 'source rock control' has evolved from source-rock-control hydrocarbon accumulation, to effective source-rock-control hydrocarbon accumulation, and to high-quality source-rock-control hydrocarbon accumulation. However, there are problems, such as whether high-quality source rocks exist or not? What high-quality source rocks are, and how to identify them, are yet to be agreed upon. Aimed at this issue of concern to explorationists, and taking the Beier Sag in the Hailaer Basin as an example, this paper defines the high-quality source rocks and the lower limit for evaluation of high-quality source rocks, by using the inflection point on the relationship curve of hydrocarbon (oil) expulsion, which is calculated by the material balance principle, versus total organic carbon (TOC). The results show that when TOC is low, all source rocks have limited hydrocarbon expulsion and slow growth rate, thus they cannot be high-quality source rocks. However, when TOC rises to some threshold, hydrocarbon expulsion increases significantly with TOC. This inflection point should be the lower limit of high-quality source rocks: those with TOC greater than the inflection-point value are high-quality source rocks. In addition, the lower limit of high-quality source rocks is also related to the type and maturity of organic matters in the source rocks, as well as the mineral components of the source rocks affecting the residual hydrocarbons. Theoretically, the lower limit of high-quality source rocks depends on geological conditions rather than being a constant value. However, for the sake of simplicity and practicability, in this paper TOC=2.0% is regarded as the lower limit of high-quality source rocks. The examination of such standard in the work area indicates that the high-quality source rocks in members K 1 n 2 and K 1 n 1 of the Nantun formation contribute 76% and 82% to oil generation, and 96% and 91% to oil expulsion , respectively. The distribution of high-quality source rocks is also closely related to the distribution of hydrocarbon reservoirs in the region, demonstrating that high-quality source rocks control hydrocarbon accumulation.Lu Shuangfang Chen Fangwen Li Jijun Wang Weiming Li Huiguang Cao Ruicheng Ma Yanling 2012Petroleum Science2012,9,1:7
19Pollen record from red clay sequence in the central Loess Plateau between 8.10 and 2.60Ma显示文摘The Late Miocene and Pliocene are the key periods for understanding the origin and development of the present Asian monsoon circulations and ecologic environ-ments. Here we present a pollen record from Chaona Red Clay section located in the central Loess Plateau in attempt to establish the histories of vegetation and associated climate changes between 8.10 and 2.60 Ma. Our results show that Gramineae-dominated woodland-grasslands developed in this region with Cedrus- and Pinus-characterized montane coniferous forests distributing in higher elevations from 8.10 to 6.73 Ma, probably suggesting a semi-humid climate in a warm-temperate zone. A subsequent expansion of Ulmus- dominated deciduous forests and a synchronous increase of Gramineae-dominated grassland reflect a warmer and more humid climate between 6.73 and 5.67 Ma. The vegetation changed to an Artemisia- and Gramineae-characterized steppe in lower elevations and to a coniferous forest in higher elevations from 5.67 to 3.71 Ma, implying probably a warm and semiarid climate in lowland and hill, and a colder and moister climate in mountain. During this period, a consider-able warmer and more humid climate occurred between 4.61 and 4.07 Ma as indicated by pollen assemblages. The period between 3.71 and 2.58 Ma was characterized by the disap-pearance of Cedrus and Tsuga and also by an abrupt expan-sion of Cupressaceae, reflecting a drastic enhancement of monsoon-related climatic seasonality.MA Yuzhen WU Fuli FANG Xiaomin LI Jijun AN Zhisheng WANG Wei 2005Chinese Science Bulletin2005,50,19:7
20Dating and genesis of the upper Weihe River terraces in Longxi basin,China显示文摘Seven terraces along the Weihe River in Longxi basin have been investigated. These terraces all consist of archetypal duality in structure, namely the floodplain deposits and the layer of gravels overlaid by varying thickness of the loess. By resorting to various dating approaches such as palaeomagnetic, optically stimulated luminescenece (OSL), 14C and loess-paleosol sequence, we provide preliminary timing of these seven terraces along upper Weihe River. Analysis on sedimentation characteristics and dating of these terraces showed that seven terraces may be jointly generated by tectonic uplifts and climatic changes. Tectonic uplifts may accommodate initial river incision, and climatic change may be responsible for processes of subsequent channel widening and aggradation. Aggradation normally occurs during glacial periods, in contrast to down-cuttings during transitions from glacial to interglacial period. Moreover, on the basis of the timings and heights of these terraces, we infer that the long-term rate of river incision was determined to be 0.2 m/kyr during the last 870 kyr, which differs from other river incision rates. This discrepancy may reflect spatio-temporal differentiation of tectonic activities in the Qinling orogenic belt during the Pleistocene.Pan Baotian Liu Xiaofeng Gao Hongshan Wang Yong Li Jijun 2007Progress in Natural Science:Materials International2007,17,11:7
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