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Characteristics of geological structures in Shiling and Zhuanshanhu areas of Yehe Uplift,NE China
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作者 GUAN Yue YU Yinghua +1 位作者 ZHANG Yaxiong YUAN Hongqi 《Global Geology》 2024年第2期105-120,共16页
The basin marginal fault system is the key to understand the formation and evolution of Songliao Basin.In order to investigate the influence of marginal fault system on the structural evolution of Songliao Basin,a com... The basin marginal fault system is the key to understand the formation and evolution of Songliao Basin.In order to investigate the influence of marginal fault system on the structural evolution of Songliao Basin,a comprehensive study was conducted on Shiling Town and Zhuanshanhu area of Yehe Town in Siping City of Jilin Province,where is the southeastern margin of the Songliao Basin and there are a series of well-exposed fault,fold and intrusive bodies belonging to the main marginal fault system of the Songliao Basin known as the Jiamusi-Yitong(Jia-Yi)fault zone.Through profile measurement and field investigation,samples with various lithologies and distinctive features were collected.Detailed field and laboratory works include component and microstructure analysis of these samples,rock-rock contact analysis,main strike measurement and statistics analysis.These data reveal the structural characteristics of the fold,fault and intrusive bodies in the study area.The research results show that the folds are distributed in the Mesozoic strata near the main fault of the eastern branch of the Jia-Yi fault zone,and the folded strata involve the Cretaceous Denglouku and Quantou formations.In addition,the section is dominated by high-angle strikeslip thrust faults.Light-colored veins and dark-colored veins are extensively distributed in the exposed granites.Statistical analysis of joint and fault attitudes in the study area reveals a right-lateral strike-sliping along the main fault.The large-scale right-lateral strike-slip and thrust fault system in Shiling Town occurred in right-lateral transpressive stage in Late Cretaceous.Based on the results above,tectonic evolution sequence in Shiling section of the Jia-Yi fault zone during the Mesozoic can be divided into five stages:Middle Jurassic left-lateral ductile strike-slip stage,Late Jurassic compression stage,Early Cretaceous tension stage,Early Cretaceous extension stage and Late Cretaceous right-lateral transpressive stage.These may have important constraint on understanding the Mesozoic evolution of the Songliao Basin. 展开更多
关键词 Jia-Yi fault structural characteristics evolution sequence Shiling Zhuanshanhu northern segment Tanlu fault
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Effect of structural characteristics distribution on strength demand and ductility reduction factor of MDOF systems considering soil-structure interaction
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作者 Behnoud Ganjavi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期205-220,共16页
It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performan... It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performance of fixed-base buildings has been investigated by researchers during the past two decades. However, no investigation has yet been carried out for the case of soil-structure systems. In the present study, through intensive parametric analyses of 21,600 linear and nonlinear MDOF systems and considering five different shear strength and stiffness distribution patterns, including three code-specified patterns as well as uniform and concentric patterns subjected to a group of earthquakes recorded on alluvium and soft soils, the effect of structural characteristics distribution on the strength demand and ductility reduction factor of MDOF fixed-base and soil-structure systems are parametrically investigated. The results of this study show that depending on the level of inelasticity, soil flexibility and number of degrees-of-freedoms (DOFs), structural characteristics distribution can significantly affect the strength demand and ductility reduction factor of MDOF systems. It is also found that at high levels of inelasticity, the ductility reduction factor of low-rise MDOF soil-structure systems could be significantly less than that of fixed-base structures and the reduction is less pronounced as the number of stories increases. 展开更多
关键词 soil-structure interaction MDof systems structural characteristic distribution inelastic behavior strength demand ductility reduction factor
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Diagnostic Study on the Structural Characteristics of a Typical Mei-yu Front System and Its Maintenance Mechanism 被引量:23
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作者 JIANG Jianying(蒋建莹) +1 位作者 NI Yunqi(倪允琪) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第5期802-813,共12页
In this paper, a typical mei-yu front process with heavy rainfall from June 12 to 15 in 1998 is analyzed. The results show that the mei-yu front is a front system which consists of an iso-theta(e) dense area with stro... In this paper, a typical mei-yu front process with heavy rainfall from June 12 to 15 in 1998 is analyzed. The results show that the mei-yu front is a front system which consists of an iso-theta(e) dense area with strong horizontal gradient, a deep-convective cloud tower band, a passageway transporting warm and moist air flow from the summer monsoon surge in the mid and low levels to the south of the mei-yu front, and a migrating synoptic scale trough to the north of the mei-yu front, which transports cold and dry air southward in the mid and upper levels. The maintenance of the mei-yu front is realized by: (1) is a positive feedback between the moist physical process enhancing frontogenesis and the development of the strong convective system in front of the mei-yu front; (2) the sustaining system to the north of the mei-yu front which is a migrating synoptic scale trough transporting cold and dry air to the mei-yu front and positive vorticity to the mesoscale system in front of the mei-yu front. 展开更多
关键词 mei-yu front structural characteristics maintenance mechanism moist physical process
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Structural Characteristics and Evolution of a Weighted Sino-US Container Shipping Network
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作者 ZHANG Tiantian XI Daping +3 位作者 JIANG Wenping FENG Yuhao WANG Chuyuan HU Xini 《Chinese Geographical Science》 SCIE CSCD 2024年第5期810-828,共19页
This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constru... This study selected the Sino-US route data from the top 30 global container liner companies between December 1,2019,and December 29,2019,as the data source utilizing the complex network research methodology.It constructs a Sino-US container shipping network through voyage weighting and analyzes the essential structural characteristics to explore the network’s complex structural fea-tures.The network’s evolution is examined from three perspectives,namely,time,space,and event influence,aiming to comprehens-ively explore the network’s evolution mechanism.The results revealed that:1)the weighted Sino-US container shipping network exhib-its small-world and scale-free properties.Key hub ports in the United States include NEW YORK NY,SAVANNAH GA,LOS ANGELES CA,and OAKLAND CA,whereas SHANGHAI serving as the hub port in China.The geographical distribution of these hub ports is uneven.2)Concerning the evolution of the weighted Sino-US container shipping network,from a temporal perspective,the evolution of the regional structure of the entire Sino-US region and the Inland United States is in a stage of radiative expansion and de-velopment,with a need for further enhancement in competitiveness and development speed.The evolution of the regional structure of southern China and Europe is transitioning from the stage of radiative expansion and development to an advanced equilibrium stage.The shipping development in Northern China,the Western and Eastern United States,and Asia is undergoing significant changes but faces challenges of fierce competition and imbalances.From a spatial perspective,the rationality and effectiveness of the improved weighted Barrat-Barthelemy-Vespignani(BBV)model are confirmed through theoretical derivation.The applicability of the improved evolution model is verified by simulating the evolution of the weighted Sino-US container shipping network.From an event impact per-spective,the Corona Virus Disease 2019(COVID-19)pandemic has not fundamentally affected the spatial pattern of the weighted Sino-US container shipping network but has significantly impacted the network’s connectivity.The network lacks sufficient resilience and stability in emergency situations.3)Based on the analysis of the structural characteristics and evolution of the weighted Sino-US con-tainer shipping network,recommendations for network development are proposed from three aspects:emphasizing the development of hub ports,focusing on the balanced development of the network,and optimizing the layout of Chinese ports. 展开更多
关键词 container shipping network structure characteristics network evolution voyage weighting improved Barrat-Barthelemy-Vespignani(BBV)model
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Different characteristics of the structure of atmospheric boundary layer between dry and rainy periods over the northern Tibetan Plateau 被引量:6
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作者 Ishikawa Hirohiko Shinya Ogino 《Research in Cold and Arid Regions》 2011年第6期509-516,共8页
In this paper, based on in-situ observational data of the Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan'Plateau (CAMP-Tibet), structure of the Atmospheric Bou... In this paper, based on in-situ observational data of the Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan'Plateau (CAMP-Tibet), structure of the Atmospheric Boundary Layer (ABL) was preliminarily studied during the dry and rainy seasons. The main results show: (a) Diurnal variation of the ABL is obvious over the northern Tibetan Plateau area. The height of the ABL is different with the season change, which ranges from 2,211 m to 4,430 m during the pre-monsoon season and from 1,006 m to 2,212 m during the monsoon season. The ABL height is higher during the dry period than during the rainyigeriod. (b) The humidity is lower during the dry period than during the rainy period, and there are reverse humidity during both periods. (c) Horizontal wind direction is mostly west during the dry period, east under the height of 2,500 m and west above the height of 2,500 m during the rainy period. The wind speed is low during both the rainy and dry periods in the lower ABL layer. The wind speed is stronger within the upper ABL during the dry period than dtn-ing the rainy period. 展开更多
关键词 Tibetan Plateau structure characteristics alrnospheric boundary layer dry period rainy period
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In-situ experimental investigation of the influence of structure characteristics on subway-induced building vibrations 被引量:1
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作者 Feng Shijin Li Fuhao +2 位作者 Zhang Xiaolei Dong Guowei Li Jianping 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期673-685,共13页
Many types of buildings have been widely constructed in the vicinity of subway lines in China.Normal life and business activities are hampered by excessive subway-induced vibrations.This study aims to determine the in... Many types of buildings have been widely constructed in the vicinity of subway lines in China.Normal life and business activities are hampered by excessive subway-induced vibrations.This study aims to determine the influence of structure characteristics on structure-borne vibrations,generally based on experimental results.Vibration measurements were performed in four typical sites in Wuxi,China,involving over-track buildings,along-track buildings,frame structure buildings and a masonry building.Special structure designs like structure transfer floor were also included.Then,the captured data was analyzed in the time domain and the frequency domain.Furthermore,the influence of building location,structure type and structure layout was investigated.Finally,vibrations were evaluated with ISO and Chinese criteria and structure optimization for vibration attenuation was proposed.It is found that over-track buildings are more severely affected than along-track buildings.Higher frequency contents(20‒60 Hz)in over-track buildings and lower frequency contents(0‒10 Hz)in along-track buildings should be seriously considered in vibration control.Weaker structure member joints and lower material strength would be beneficial to over-track buildings while the inverse situation would be beneficial to along-track buildings.The application of structure transfer floor‒generally stiffer structure members and structure discontinuity‒is also beneficial. 展开更多
关键词 subway-induced vibration structure characteristic vibration evaluation vibration control structure optimization
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The Characteristics of Ore-Controlling Structure in Baoshan Cu-Pb-Zn Polymetallic Deposit,Hunan Province 被引量:3
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作者 QI Fan-yu1,ZHANG Zhi1,2,LI Yong-sheng1,ZHEN Shi-min1,JIA De-long1,GONG Fan-ying1,GONG Xiao-dong1,HE Peng1(1.School of Earth & Resources,China University of Geosciences Beijing,Beijing 100083,China 2.Development and Research Center,Beijing 100037 China) 《矿物学报》 CAS CSCD 北大核心 2011年第S1期823-824,共2页
The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part ... The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian. 展开更多
关键词 PB The characteristics of Ore-Controlling structure in Baoshan Cu-Pb-Zn Polymetallic Deposit Hunan Province ZN CU
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Three-dimensional velocity structure and tectonic characteristics of earthquake area in Yibin 被引量:1
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作者 Ma Yong Bi Jin-Meng and Gao Lei 《Applied Geophysics》 SCIE CSCD 2019年第3期267-276,394,共11页
In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal par... In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal parameters and three-dimensional(3 D)body-wave high-resolution velocity structures at depths of 0–30 km were retrieved by double-difference tomography.Results show that there is a good correspondence between the spatial distribution of the relocated earthquakes and velocity structures,which were concentrated mainly in the high-velocity-anomaly region or edge of high-velocity region.Velocity structure of P-and S-waves in the Yibin area clearly shows lateral inhomogeneity.The distribution characteristics of the P-and S-waves near the surface are closely related to the geomorphology and geologic structure.The low-velocity anomaly appears at the depth of 15–25 km,which is affected by the lower crust current.The Junlian–Gongxian and Gongxian–Changning earthquake areas,which are the two most earthquake-prone areas in the Yibin region,clearly differ in earthquake distribution and tectonic characteristics.We analyzed the structural characteristics of the Junlian–Gongxian and Gongxian–Changning earthquake areas on the basis of the 3 D bodywave velocity structures in the Yibin region.We found that although most seismicity in the Yibin area is caused by fluid injection,the spatial position of seismicity is controlled by the velocity structures of the middle and upper crust and local geologic structure.Fine-scale 3 D velocity structures in the Yibin area provide important local reference information for further understanding the crustal medium,seismogenic structure,and seismicity. 展开更多
关键词 Yibin area double-difference tomography method 3D P・wave and S・wave velocity structure structural characteristics
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Characteristic Functional Structure of Infinitesimal Symmetry Transformations for Nonholonomic System 被引量:1
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作者 张宏彬 陈立群 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期134-138,共5页
It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsform... It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsformation function and is manifestly dependent upon constants of motion of th e system. An example was given to illustrate the applicability of the results. 展开更多
关键词 analytical mechanics nonholonomic system velocity-dependent infinitesimal symmetry transformation characteristic functional structure constant of motion.
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Structure characteristics and adhesive property of humic substances extracted with different methods
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作者 张元波 韩桂洪 +4 位作者 姜涛 黄艳芳 李光辉 郭宇峰 杨永斌 《Journal of Central South University》 SCIE EI CAS 2011年第4期1041-1046,共6页
The structure characteristics and adhesive property of humic substance(HS) extracted with different methods were mainly studied by terms of elementary analysis,visible spectrum,FT-IR spectroscopy,viscosity,adsorption ... The structure characteristics and adhesive property of humic substance(HS) extracted with different methods were mainly studied by terms of elementary analysis,visible spectrum,FT-IR spectroscopy,viscosity,adsorption and pelletizing experiments.The results show that HSs extracted with new method(HS-a) own higher degree of aromatization and polymerization,larger relative molecular mass and more polar functional groups than HS extracted with usual method(HS-b).The viscosity of HS-b is about 30-40 mPa·s lower than that of HS-a.The maximum adsorption amounts of HS-a and HS-b onto iron concentrates are 9.11 mg/g and 8.08 mg/g,respectively.Meanwhile,HS-a has a better performance than HS-b in the practical application for pelletizing of iron concentrates.The difference in agglomeration behaviors with iron concentrates lies in the differences of the structure characteristics of HSs.With higher content of polar functional groups,larger relative molecular mass and viscosity of HSs,the agglomeration behavior is improved. 展开更多
关键词 humic substances structure characteristic agglomeration behaviour green ball
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Application of Characteristics of Seismogenic Structures in the Determination of Parameter of Potential Seismic Source Areas
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作者 Zhou Bengang 《Earthquake Research in China》 2005年第4期430-441,共12页
The characteristics of seismogenic structures are an important basis for delineating the potential seismic source areas and determining the annual occurrence rate of earthquakes. The potential seismic source area does... The characteristics of seismogenic structures are an important basis for delineating the potential seismic source areas and determining the annual occurrence rate of earthquakes. The potential seismic source area does not only have the intension that “this area has the possibility for destructive earthquakes to occur in the future" but also means that earthquakes of high magnitude interval have the characteristics of similar recurrence. When determining the seismic activity parameters of a statistical unit, some active tectonic blocks in the unit may have different background earthquakes. In order to better reflect the heterogeneity in space of seismic activities, it is necessary to divide the potential seismic source areas into three orders. By analyzing the recurrence characteristics of earthquakes of high magnitude interval in the potential source area and calculating the occurrence probability of earthquakes of high magnitude interval in the potential seismic source area in the time window for prediction, the average annual occurrence rate of earthquakes can be obtained by the method of probability equivalent conversion in the time window for prediction. This would be helpful for considering the recurrence characteristics of strong earthquakes in potential source areas within the framework of seismic risk analysis of China. Besides, the insufficient frequency of characteristic earthquakes of the next high magnitude interval in the potential source area and the heterogeneity of strong earthquakes on seismogenic structures are analyzed to see their application in seismic risk analysis. 展开更多
关键词 Potential seismic source area Seismogenic structure characteristics Seismic risk analysis
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A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques
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作者 Md.Ghulam Saber Rakibul Hasan Sagor Md.Ruhul Amin 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期132-135,共4页
The linear dispersion relation of a trapezoidally corrugated slow wave structure (TCSWS) is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency... The linear dispersion relation of a trapezoidally corrugated slow wave structure (TCSWS) is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency range. The dispersion relation is solved by utilizing the Rayleigh-Fourier method by expressing the radial function in terms of the Fourier series. A highly accurate synthetic technique is also applied to determine the complete dispersion characteristics from experimentally measured resonances (cold test). Periodic structures resonate at specific frequencies when the terminals are shorted numerical calculation, synthetic technique and cold appropriately. The dispersion characteristics obtained from test are compared, and an excellent agreement is achieved. 展开更多
关键词 of on A Comparative Study of Dispersion characteristics Determination of a Trapezoidally Corrugated Slow Wave structure Using Different Techniques in been IS
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Illumination and Voltage Dependence of Electrical Characteristics of Au/0.03 Graphene-Doped PVA/n-Si Structures via Capacitance/Conductance-Voltage Measurements
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作者 SAHAR Alialy AHMET Kaya +1 位作者 I Uslua EMSETTIN Altmdal 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第11期92-96,共5页
Au/n-Si (MS) structures with a high dielectric interlayer (0.03 graphene-doped PVA) are fabricated to investigate the illumination and voltage effects on electrical and dielectric properties by using capacitance-v... Au/n-Si (MS) structures with a high dielectric interlayer (0.03 graphene-doped PVA) are fabricated to investigate the illumination and voltage effects on electrical and dielectric properties by using capacitance-voltage (C-V) and conductance-voltage (G/w-V) measurements at room temperature and at 1 MHz. Some of the main electrical parameters such as concentration of doping atoms (ND), barrier height ( ФB( C - V) ), depletion layer width (WD) and series resistance (Rs) show fairly large illumination dispersion. The voltage-dependent profile of surface states (Nss) and resistance of the structure (Ri ) are also obtained by using the dark-illumination capacitance (Cdark- Cm) and Nicollian-Brews methods, respectively, For a clear observation of changes in electrical parameters with illumination, the values of ND, WD, ФB(O- V) and Rs are drawn as a function of illumination intensity. The values of ND and WD change almost linearly with illumination intensity. On the other hand, Rs decreases almost exponentially with increasing illumination intensity whereas ФB(C - V) increases. The experimental results suggest that the use of a high dielectric interlayer (0.03 graphene-doped PVA) considerably passivates or reduces the magnitude of the surface states. The large change or dispersion in main electrical parameters can be attributed to generation of electron-hole pairs in the junction under illumination and to a good light absorption. All of these experimental results confirm that the fabricated Au/0.03 graphene-doped PVA/n-Si structure can be used as a photodiode or a capacitor in optoelectronic applications. 展开更多
关键词 SI PVA Illumination and Voltage Dependence of Electrical characteristics of Au/0.03 Graphene-Doped PVA/n-Si structures via Capacitance/Conductance-Voltage Measurements
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Boundary Layer Characteristics and Numerical Simulation Analysis of Winter Dense Fog in Nanjing 被引量:3
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作者 马国忠 银燕 《Meteorological and Environmental Research》 CAS 2010年第10期25-28,32,共5页
Based on the boundary layer data of winter dense fog in 2007 from Nanjing University of Information Science & Technology,the profile characteristics of temperature,wind direction,wind speed and humidity in a dense... Based on the boundary layer data of winter dense fog in 2007 from Nanjing University of Information Science & Technology,the profile characteristics of temperature,wind direction,wind speed and humidity in a dense fog weather on December 13-14 in 2007 were analyzed,as well as their evolution laws in the formation and dispersion of fog,and the boundary layer characteristics of winter dense fog in Nanjing were revealed,while the development of fog was simulated by means of mesoscale numerical model.The results showed that the formation and dispersion of fog was greatly affected by inversion and humidity in the surface layer,and the wind direction in the surface layer also had effect on the formation and dispersion of advection fog.Mesoscale numerical model could preferably simulate the evolution of temperature,humidity,vertical speed in the development of fog,and the simulation of water vapor content in the fog could forecast the formation and dispersion of fog. 展开更多
关键词 Tethered launch detection Inversion in atmospheric boundary layer Vertical structure characteristic Numerical simulation China
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Denoising of Chinese calligraphy tablet images based on run-length statistics and structure characteristic of character strokes 被引量:7
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作者 ZHANG Jun-song YU Jin-hui +1 位作者 MAO Guo-hong YE Xiu-zi 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1178-1186,共9页
In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu... In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method. 展开更多
关键词 DENOISING Tablet images structure characteristics Character strokes
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Effect of Organic Manure Application on Physical Properties and Humus Characteristics of Paddy Soil 被引量:9
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作者 DOUSEN CHENEN-FENG 《Pedosphere》 SCIE CAS CSCD 1994年第2期127-135,共9页
Long-term field experiment was established in 1978 on a coastal paddy soil to determine the effect of applicationof pig manure, rice straw and chemical N fertilizer on the physical property and humus characteristics o... Long-term field experiment was established in 1978 on a coastal paddy soil to determine the effect of applicationof pig manure, rice straw and chemical N fertilizer on the physical property and humus characteristics of soil . Resultsshowed that the porosity, the microstructural coefficient, the reactivities of organic C and N, the ΔlogK value, thedegree of oxidation stability, the contents of O-alkyl C and alkyl C, and the ratio of aliphatic C to aromatic C ofhumic acid from soils received organic manure increased, whereas, the ratio of < 10 μm to >10 μm ofmicroaggregates, the humification degree of humus, the degree of organo-mineral complexation, the number-averagemolecular weight, the C/ H ratio. the contents of carboxyl and aromatic C of HAs in them decreased. These resultsindicated that the application of organic manure not only improved the physical property of the paddy soil but alsomade the HA more aliphatic in structure and younger in origin. 展开更多
关键词 humic acid organic manure poddy soil. structural characteristics
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Structural Characteristics and their Significance for Hydrocarbon Accumulation in the Northern Slope of the Central Sichuan Paleo-uplift 被引量:4
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作者 TIAN Xingwang LIU Guangdi +13 位作者 LUO Bing YANG Yu WEN Long ZHANG Benjian CHEN Xiao SU Guiping SONG Zezhang PENG Hanlin ZHOU Gang YAN Wei YANG Dailin WANG Yunlong SUN Yiting DOU Shuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第4期1451-1470,共20页
Based on 2D and 3D seismic data,the latest drilling data and field outcrop data of the northern slope of the Central Sichuan paleo-uplift,the structural analysis method is used to analyze unconformity development char... Based on 2D and 3D seismic data,the latest drilling data and field outcrop data of the northern slope of the Central Sichuan paleo-uplift,the structural analysis method is used to analyze unconformity development characteristics and fault characteristics during the key structural transformation period,discussing the influence of the structural characteristics on the hydrocarbon accumulation of deep carbonate rocks.The results show that:(1)The two key unconformities of the Tongwan and Caledonian periods were primarily developed in deep carbonate rocks.Firstly,Tongwan’s unconformities are characterized by regional disconformities between the second and third members of the Dengying Formation,the top formation of the Sinian and the lower Cambrian,strips of which zigzag through the north and south sides of the study area.Secondly,the Caledonian unconformity is characterized by a regional unconformable contact between the lower Permian and the ower Paleozoic strata.From NE to SW,the age of the strata,which were subject to erosion,changes from new to old,the denudation distribution showing as a nose-shaped structure which inclines towards the ENE.(2)Boundary fault and transtensional strike-slip faults developed in the Sinian to Paleozoic strata.In profile,there are three types of structural styles:steep and erect,flower structures,’Y’and reversed’Y’type faults.In plane view,the Sinian developed extensional boundary faults extending in an almost NS direction,strike-slip faults developing and extending linearly in approximately EW,WNW and NE strikes in the Cambrian,with characteristically more in the south and less in the north.(3)The faults in the northern slope show obvious zonal deformations in transverse view as well as significant stages and stratified activity in a longitudinal direction.Among them,the activity of faults in the Sinian was the strongest,followed by the activity in the Cambrian period,the activity intensity of faults in the Permian period being the weakest.This fault activity can be divided into four periods:Sinian,Cambrian-Permian,the early Indosinian period and the late Indosinian-Himalayan period,the transtensional strikeslip faults being the products of oblique extensions of pre-existing weak zones in the Xingkai and Emei taphrogenesis,with a particular inheritance in the main faults.(4)Combined with hydrocarbon accumulation factors,it is considered that the epigenetic karstification of the Tongwan and Caledonian unconformities in the northern slope controlled the formation and distribution of carbonate karst reservoirs over a large area,also acting as a good pathway for oil and gas migration.The extensional faults developed at the margin of the NS trending rift,controlling the sag-platform sedimentary pattern in the Dengying Formation of the Sinian.Strike-slip faults in NE,WNW and ENE directions may control the microgeomorphological pattern inside the platform and intensify the differential distribution of grain beach facies.The multi-stage hereditary activity of strike-slip faults not only improved the porosity and permeability of the reservoirs,but also acted as the main channel of oil and gas migration,providing favorable conditions for the development of the current multi-layer gasbearing scenario in the northern slope of the Central Sichuan Basin. 展开更多
关键词 northern slope of paleo-uplift UNCONFORMITY structural characteristics hydrocarbon accumulation Central Sichuan paleo-uplift Sichuan Basin
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Effects of rapid quenching on structure and cycle stability of La-Mg-Ni-Co type hydrogen storage alloy 被引量:4
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作者 DONG Xiaoping Lü Fanxiu ZHANG Yanghuan YANG Liying FENG Meng WANG Xinlin 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期207-212,共6页
In order to improve the cycle stability of La-Mg-Ni-Co type alloy electrode, rapid quenching technology was employed. The effects of rapid quenching on the microstructure and cycle stability of the alloy were investig... In order to improve the cycle stability of La-Mg-Ni-Co type alloy electrode, rapid quenching technology was employed. The effects of rapid quenching on the microstructure and cycle stability of the alloy were investigated. The obtained results show that the La2Mg(Ni0.85Co0.15)9M0.1 (M=B, Cr) alloy electrodes are composed of (La, Mg)Ni3 phase, LaNi5 phase and a small amount of the LaNi2 phase. A trace of the Ni2B phase exists in the as-cast MB alloy, and the Ni2B phase in the alloy nearly disappears after rapid quenching. Rapid quenching technology can slightly improve the cycling life of the alloy. When the quenching rate increases from 0 m·s-1 (As-cast is defined as quenching rate of 0 m·s-1) to 30 m·s-1, the cycle lives of the MB, MCr alloys enhance from 86 and 87 cycles to 106 and 119 cycles, respectively. On the other hand, the average capacity decay rates of the MB, MCr alloys decrease from 1.7172 and 1.7178 mAh·g-1·cycle-1 to 1.5751 and 1.3060 mAh·g-1·cycle-1 after 86 charge-discharges cycling, respectively. 展开更多
关键词 rapid quenching La-Mg-Ni-Co type hydrogen storage alloy structure characteristics cycle stability
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Effect of Pig Manure Application on Structural Characteristics of Humic Acids in Brown Soil 被引量:5
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作者 DOUSEN TANSHI-WEN 《Pedosphere》 SCIE CAS CSCD 1991年第4期345-354,共10页
The effect of application of pig manure (PM) on the structural characteristics of humic acids (HAs) of brown soil was studied in field and incubation experiments. The results showed that the number-average molecular w... The effect of application of pig manure (PM) on the structural characteristics of humic acids (HAs) of brown soil was studied in field and incubation experiments. The results showed that the number-average molecular weights (Mn), the ratios of C/ H, C/ N and O/C, the contents of carboxyl and phenolic hydroxyl groups, the content ofaromatic C, the values of E2, E4and λ Exmax of HAs all decreased; whereas, the contents of alkyl C and O-alkyl C, the ratio of carboxyl to phenolic hydroxyl groups, the degree of oxidation stability, the absorption intensity at 285 mμ (UV), and 2920cm-1 of HAs increased after the application of PM. The above results indicated that the molecular structure of HAs tended to be more aliphatic and simpler after the application of PM. 展开更多
关键词 humic acid pig manure application structural characteristics
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Electrical Structure and Fault Features of Crust and Upper Mantle beneath the Western Margin of the Qinghai-Tibet Plateau:Evidence from the Magnetotelluric Survey along Zhada-Quanshui Lake Profile 被引量:3
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作者 金胜 叶高峰 +2 位作者 魏文博 邓明 景建恩 《Journal of China University of Geosciences》 SCIE CSCD 2007年第4期326-333,共8页
The magnetotelluric (MT) survey along the Zhada (札达)-Quanshui (泉水) Lake profile on the western margin of the Qinghai (青海)-Tibet plateau shows that the study area is divided into three tectonic provinces ... The magnetotelluric (MT) survey along the Zhada (札达)-Quanshui (泉水) Lake profile on the western margin of the Qinghai (青海)-Tibet plateau shows that the study area is divided into three tectonic provinces by the Yalung Tsangpo and Bangong (班公)-Nujiang (怒江) sutures. From south to north these are the Himalayan terrane, Gangdise terrane, and Qiangtang (羌塘) terrane. For the study area, there are widespread high-conductivity layers in the mid and lower crust, the top layers of which fluctuate intensively. The high-conductivity layer within the Gangdise terrane is deeper than those within the Qiangtang terrane and the Himalaya terrane, and the deepest high-conductivity layer is to the south of the Bangong-Nujiang suture. The top surface of the high-conductivity layer in the south of the Bangong-Nujiang suture is about 20 km lower than that in the north of it. The high-conductivity layer within the Gangdise terrane dips toward north and there are two high-conductivity layers within the crust of the southern Qiangtang terrane. In the upper crust along the profile, there are groups of lateral electrical gradient zones or distortion zones of different scales and occurrence indicating the distribution of faults and sutures along the profile. According to the electrical structure, the structural characteristics and space distribution of the Yalung Tsangpo suture, Bangong.Nujiang suture, and the major faults of Longmucuo (龙木错) and Geerzangbu are inferred. 展开更多
关键词 west margin of Qinghai-Tibet plateau MT high-conductivity layers of crust electrical structure structural characteristics of fault.
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