检索结果-南通市图书馆

Lithofacies paleogeography mapping and reservoir prediction in tight sandstone strata: A case study from central Sichuan Basin, China

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2017年第5期8卷 961-975页

作者： Yuan Zhong Lu Zhou Xiucheng Tan Chengbo lian Hong Liu Jijia Liao Guang Hu Mingjie Liu jian Cao State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China Department of Earth Science and Technology Southwest Petroleum University Chengdu 610500 China School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China

Sand-rich tight sandstone reservoirs are potential areas for oil and gas exploration. However, the high ratio of sandstone thickness to that of the strata in the formation poses many challenges and uncertainties to traditional lithofacies paleogeography mapping. Therefore, the prediction of reservoir sweet spots has remained problematic in the field of petroleum exploration. This study provides new insight into resolving this problem, based on the analyses of depositional characteristics of a typical modern sand-rich formation in a shallow braided river delta of the central Sichuan Basin, China. The varieties of sand-rich strata in the braided river delta environment include primary braided channels,secondary distributary channels and the distribution of sediments is controlled by the successive superposed strata deposited in paleogeomorphic valleys. The primary distributary channels have stronger hydrodynamic forces with higher proportions of coarse sand deposits than the secondary distributary channels. Therefore, lithofacies paleogeography mapping is controlled by the geomorphology, valley locations, and the migration of channels. We reconstructed the paleogeomorphology and valley systems that existed prior to the deposition of the Xujiahe Formation. Following this, rock-electro identification model for coarse skeletal sand bodies was constructed based on coring data. The results suggest that skeletal sand bodies in primary distributary channels occur mainly in the valleys and low-lying areas,whereas secondary distributary channels and fine deposits generally occur in the highland areas. The thickness distribution of skeletal sand bodies and lithofacies paleogeography map indicate a positive correlation in primary distributary channels and reservoir thickness. A significant correlation exists between different sedimentary facies and petrophysical properties. In addition, the degree of reservoir development in different sedimentary facies indicates that the mappin

关键词： Sand-rich strata Reservoir “sweet spot” Paleogeomorphology Primary distributary channel Lithofacies paleogeography

Effects of the total physical activity and its changes on incidence, progression, and remission of hypertension

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第3期18卷 175-184页

作者： Can CAI Fang-Chao LIU jian-Xin LI Ke-Yong huang Xue-Li YANG Ji-Chun CHEN Xiao-Qing LIU Jie CAO Shu-Feng CHEN Chong SHEN Ling YU Fang-Hong LU Xian-Ping WU lian-Cheng ZHAO Ying LI Dong-Sheng HU jian-Feng huang Xiao-Yang ZHOU Xiang-Feng LU Dong-Feng GU Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060China Key Laboratory of Cardiovascular Epidemiology&Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Tianjin Key Laboratory of Environment Nutrition and Public HealthDepartment of Occupational and Environmental HealthSchool of Public HealthTianjin Medical UniversityTianjin 300070China Division of Epidemiology Guangdong Provincial People’s Hospital and Cardiovascular InstituteGuangzhou 510080China Department of Epidemiology and Biostatistics School of Public HealthNanjing Medical UniversityNanjing 211166China Department of Cardiology Fujian Provincial HospitalFuzhou 350014China Cardio-Cerebrovascular Control and Research Center Institute of Basic MedicineShandong Academy of Medical SciencesJinan 250062China Sichuan Center for Disease Control and Prevention Chengdu 610041China Department of Epidemiology and Health Statistics School of Public HealthShenzhen University Health Science CenterShenzhen 518060China

OBJECTIVES Moderate to vigorous physical activity is recommended to prevent hypertension according to the current ***,the degree to which the total physical activity(TPA)and its changes benefit normotensives and hypertensives is *** aimed to examine the effects of TPA and its changes on the incidence,progression,and remission of hypertension in the large-scale prospective *** A total of 73,077 participants(55,101 normotensives and 17,976 hypertensives)were eligible for TPA *** a mean follow-up of 7.16 years(394,038 person-years),12,211 hypertension cases were *** was estimated as metabolic equivalents and categorized into *** proportional hazards regression and multivariable logistic regression were used to estimate associations of TPA and changes in TPA with incident hypertension and progression/remission of *** Compared with the lowest quartile of TPA,normotensives at the third and the highest quartile had a decreased risk of incident hypertension,with hazard ratios(HRs)of 0.86[95%confidence interval(CI):0.81−0.91]and 0.81(95%CI:0.77−0.86),*** at the highest quartile of TPA demonstrated a decreased risk of progression of hypertension[odds ratio(OR)=0.87,95%CI:0.79−0.95],and an increased probability of hypertension remission(OR=1.17,95%CI:1.05−1.29).Moreover,getting active from a sedentary lifestyle during the follow-up period could reduce 25%(HR=0.75,95%CI:0.58−0.96)risk of incident hypertension,whereas those becoming sedentary did not achieve benefit from initially being *** Our findings indicated that increasing and maintaining TPA levels could benefit normotensives,whereas higher TPA levels were needed to effectively control progression and improve remission of *** activity played undoubtedly an essential role in both primary and secondary prevention of hypertension.

关键词： hypertension remission prevention

mKdV Equation for the Amplitude of Solitary Rossby Waves in Stratified Shear Flows with a Zonal Shear Flow

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2009年第1期2卷 18-23页

作者： Song jian Yang lian-Gui Da Chao-Jiu Zhang Hui-Qin College of Mathematical Sciences Inner Mongolia UniversityHohhot 010021China College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Institute of Mechanics Chinese Academy of SciencesBeijing 100080China

In this paper,modified Korteweg-de Vries (mKdV) equations for the amplitude of solitary Rossby waves in stratified fluids with a zonal shear flow are derived by using a weakly nonlinear *** is found that the coefficients of mKdV equations depend not only on the β effect and the Visl-Brunt frequency,but also on the basic shear flow.

关键词： mKdV equation β effect shear flow Vaisala-Brunt frequency

Varietal and Seasonal Effect of Rice on the Physicochemical Properties of Rice Flakes

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2007年第4期6卷 422-429页

作者： SHU Qing-yao ZHU Xiao-yang YANG lian WU Wei-jian Peter Bucheli Institute of Nuclear Agricultural Sciences Zhejiang University Hua Jia Chi Campus Hangzhou 310029 P.R.China School of Food Science ＆ Technology Southern Yangtze University Qing Shah Campus Wuxi 214036 P.R.China Nestlé R＆D Centre Shanghai Ltd. Shanghai 201812 P.R. China

Rice-based flakes made from 7 mid-season rice varieties （4 indica and 3 japonica subspecies） and 3 early season indica varieties produced both in early and late season were studied for their main physicochemical characters, including water activity, film thickness, bulk density （BD）, ash, reducing sugars （RS）, protein, phytic acid, starch, amylose, and rapid visco analyser （RVA） viscosity profile. A significant varietal effect was found for all these parameters （P〈 0.05 or 0.01） except starch. Strong variety x season interactions were observed but the seasonal effect was less pronounced, and only significant （P〈0.01） for RS. The apparent amylose content （AAC） office flakes was significantly correlated （P〈0.01） with AAC （r=0.99） and several RVA profile parameters [e.g., final viscosity （r=0.92）] of rice flour. For rice flakes, BD was significantly correlated with AAC （r=0.82, P〈0.01） and most RVA profile parameters. The study indicates that varietal and environmental effects should be considered simultaneously for optimal production of rice grains for rice flakes manufacturing.

关键词： rice processing variety season amylose viscosity nutrition

Heterogeneity Analysis of Cucumber Canopy in the Solar Greenhouse

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2014年第12期13卷 2645-2655页

作者： QIAN Ting-ting LU Sheng-lian ZHAO Chun-jiang GUO Xin-yu WEN Wei-liang DU jian-jun Shanghai Jiao Tong University Beijing Research Center for Information Technology in Agriculture

Detailed analysis of canopy structural heterogeneity is an essential step in conducting parameters for a canopy structural model. This paper aims to analyze the structural heterogeneity of a cucumber （Cucumis sativus L.） canopy by means of analyzing leaf distribution in a greenhouse environment with natural sunlight and also to assess the effect of structural canopy heterogeneity on light interception and photosynthesis. Two experiments and four measurements were carried out in autumn 2011 and spring 2012. A static virtual three-dimensional （3D） canopy structure was reconstructed using a 3D digitizing method. The diurnal variation of photosynthesis rate was measured using CIRAS-2 photosynthesis system. The results showed that, leaf azimuth as tested with the Rayleigh-test was homogeneous at vine tip over stage but turned heterogeneous at fruit harvest stage. After eliminating the inlfuence of the environment on the azimuth using the von Mises-Fisher method, the angle between two successive leaves was 144°;at the same time, a rule for the azimuth distribution in the canopy was established, stating that the azimuth distribution in cucumber followed a law which was positive spin and anti-spin. Leaf elevation angle of south-oriented leaves was on average 13.8° higher than that of north-oriented leaves. The horizontal distribution of light interception and photosynthesis differed signiifcantly between differently oriented leaves. East-and west-oriented leaves exhibited the highest photosynthetic rate. In conclusion, detailed analysis of canopy structural heterogeneity in this study indicated that leaf azimuth and elevation angle were heterogeneous in cucumber canopy and they should be explicitly described as they have a great impact both on light distribution and photosynthesis.

关键词： heterogeneity inclination leaf azimuth light interception photosynthesis

Single-molecule imaging of dinitrogen molecule adsorption on individual iron phthalocyanine

在线全文

学校读者我要写书评

暂无评论

Nano Research 2020年第9期13卷 2393-2398页

作者： Chengding Gu Jia Lin Zhang jian Qiang Zhong Qian Shen Xiong Zhou Kaidi Yuan Shuo Sun Xu lian Zhirui Ma Wei Chen Department of Chemistry National University of SingaporeSingapore 117543Singapore Department of Physics National University of SingaporeSingapore 117542Singapore Department of Interface Science Fritz-Haber-Institut der Max-Planck-GesellschaftBerlin 14195Germany Institute of Advanced Materials Nanjing Tech UniversityNanjing 210009China BNLMS College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School of Physical Science and Technology Shanghai Tech UniversityShanghai 200031China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China National University of Singapore(Suzhou)Research Institute Suzhou 215123China

Nitrogen fixation is a vital process for both nature and *** the nitrogenase can reduce nitrogen in ambient environment in nature,the industrialized Haber-Bosch process is a high temperature and high-pressure *** the discovery of the first dinitrogen complex in 1965,many dinitrogen complexes are prepared in a homogeneous solution to mimic the nitrogenase enzyme in ***,studies of the heterogeneous process on surface are rarely ***,molecular scale characterization for such dinitrogen complex is ***,we present a simple model system to investigate,at the single-molecule level,the binding of dinitrogen on a surface confined iron phthalocyanine(FePc)monolayer through the combination of in-situ low-temperature scanning tunneling microscopy(LT-STM)and X-ray photoelectron spectroscopy(XPS)*** iron center in FePc molecule deposited on Au(111)and highly oriented pyrolytic graphite(HOPG)surface can adsorb dinitrogen molecule at room temperature and low pressure.A comparative study reveals that the adsorption behaviors of FePc on these two different substrates are *** bond is formed between the dinitrogen and the Fe atom in the FePc molecule,which greatly modifies the electronic structure of *** bonding is reversible and can be manipulated by applying bias using a STM tip or by thermal annealing.

关键词： single-molecule dinitrogen iron phthalocyanine axial coordination

A comparison of corrosion inhibition of magnesium aluminum and zinc aluminum vanadate intercalated layered double hydroxides on magnesium alloys

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Materials Science 2018年第2期12卷 198-206页

作者： lian GUO Fen ZHANG Jun-Cai LU Rong-Chang ZENG Shuo-Qi LI liang SONG jian-Min ZENG College of Material Science and Engineering Shandong University of Science and Technology Qingdao 266590 China School of Materials Science and Engineering Guangxi University Nanning 530004 China

The magnesium aluminum and zinc aluminum layered double hydroxides intercalated with NO3^- （MgAl-NO3-LDH and ZnAl-NO3-LDH） were prepared by the coprecipitation method, and the magnesium aluminum and the zinc aluminum layered double hydroxides intercalated with VO; （MgAl-VOx-LDH and ZnAl-VOx-LDH） were prepared by the anion-exchange method. Morphologies, microstructures and chemical compositions of LDHs were investigated by SEM, EDS, XRD, FTIR, Raman and TG analyses. The immersion tests were carried to determine the corrosion inhibition properties of MgAl-VOx-LDH and ZnAl-VOx-LDH on AZ31 Mg alloys. The results showed that ZnAl-VOx-LDH possesses the best anion-exchange and inhibition abilities. The influence of treatment parameters on microstructures of LDHs were discussed. Additionally, an inhibition mechanism for ZnAl-VOx-LDH on the AZ31 magnesium alloy was proposed and discussed.

关键词： layered double hydroxides anion-exchange thermal stability magnesium alloys inhibition

Curent Situation of “Candidatus Liberibacter asiaticus” in Guangdong,China,Where Citrus huanglongbing Was First Described

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2012年第3期11卷 424-429页

作者： DENG Xiao-ling GAO Yi-di CHEN jian-chi PU Xue-lian KONG Wei-wen LI Hua-ping Laboratory of Citrus huanglongbing Research South China Agricultural University Guangzhou 510642 P.R. China San Joaquin Valley Agricultural Sciences Center USDA-ARS Parlier California 93648 USA School of Horticulture and Plant Protection Yangzhou University Yangzhou 225009 P.R. China

Citrus huanglongbing （HLB,yellow shoot disease） was first observed in the coastal Chaoshan Plain of Guangdong Province,China,in the late 19th century based on descriptions of yellow shoot symptoms. “Candidatus Liberibacter asiaticus”has been considered as a putative pathogen associated with HLB since *** about the curent prevalence of this bacterium is important for HLB control in Guangdong and also provides useful reference for HLB study *** 2007,we collected HLB symptomatic citrus samples from 16 cultivars in 12 prefecture cities,mostly in the north and west regions of Guangdong,where major citrus fruits are currently *** the 359 samples collected,241 （67.1%） were positive for “***”,distributed in 15 out of the 16 cultivars from all 12 cities,indicating the widespread prevalence of “***” in Guangdong *** detection rates varied from 16.7 to 100% depending on location and *** detection rates were found in newer citrus cultivation cities among the previously less popular but now promoted *** reviewing the citrus management and pest control practice,we believe that infected nursery stocks play a key role in the current spread of “***”.

关键词： citrus huanglongbing Candidatus Liberibacter asiaticus

新形势下大中小学师资一体化协同培养——基于虚拟教研室建设构建研究

在线全文

学校读者我要写书评

暂无评论

唐山师范学院学报 2024年第4期46卷 148-151页

作者：张静陈伟莲张连忠孙健张秀菊韩耀春苗梦秋唐山师范学院教务处河北唐山063000 唐山师范学院文学院河北唐山063000 唐山师范学院生命科学系河北唐山063000 沈阳师范大学教学质量监控与评估处辽宁沈阳110034 龙泉中学河北唐山063000

构建虚拟教研室数字化平台进行协同培养,通过灵活的管理制度进行有效管理,线上线下联动构建师资一体化协同培养共同体,加快数字化平台建设,建立定期总结与反馈机制。

关键词：大中小学师资一体化协同提质虚拟教研室