An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Research on the static nonlinear push-over analysis in the frame-shear structure used MIDAS the finite element software.Through using special wall hinge element in the MIDAS,discussed the destroy process of frame-shear structure.It points out that some other softwares,for example ETABS and SAP2000 can't achieve this analysis.
With the increasing demand of oil and gas resources caused by world economic development,the exploration and development of unconventional marine carbonate reservoir turn to hot research topics.The main seismic-geologic problems in marine carbonate exploration areas are rugged near surface,complex steep subsurface structure,deep target reflective layers,complex reservoir and so on,which make the conventional processing methods under the assumption of horizontal layered medium applied in clastic rock areas helpless.Prestack depth migration is an effective technique to improve the seismic data quality and image precision of complex structure in marine carbonate areas.In order to realize the accurate prestack depth migration in carbonate areas,the corresponding velocity analysis method must be researched first This paper has proposed a tomography velocity analysis method based on image gathers,which use the angle domain common imaging gathers(ADCIGs) by prestack depth migration with wave equation double square root operator as the gathers of velocity analysis,and get the traveltime residual from depth residual by automatic fitting method.On one hand,ADCIGs can reflect the coupling relation of velocity and depth accurately and nearly have no artifact,making high precision of traveltime residual.On the other hand,the complex reflection can decompose into upward and downward transmission fortunately in the corresponding ray tracing method,which may simplify forward problem and increase the efficiency and accuracy of sensitivity matrix calculation,leading to higher precision result in velocity analysis.Examples of the synthetic seismic-geologic dataset and real dataset in marine carbonate areas show that the velocity field inverted by this method has accurate velocity value and interface depth,generating a high quality result of prestack depth migratioa So this method can solve the velocity problem of marine carbonate exploration areas,however,low S/N prestack seismic data can impact the precision of tomography velocity analysis.
According to the theory of the outer core convection ascension body backwater on the curst of the formation of earthquake,the crust will gradually recover after the earthquake,the performance is that the crust will be stretched,the underground temperature will reduce,the precipitation will decrease.The analysis of the droughts after the earthquake whose Ms≥6.5in western China from 1976to 2008shows that quasi-six months after the earthquake occurring,there will be a drought in downstream area range(500~2000km)with the same latitude,indicating the the process of the crust recovery is a oscillation process with a certain regularity,there is a cycle of quasi-half-year.The appearing time of the quasi-halfyear is closely related to magnitude,it′s vibration increase with the enhancement of magnitude,with last2.5years for Ms=6.5earthquake and with last 5years or so for Ms=8earthquake.The two main areas of arid centers are 84°E-94°E and 105°E-115°E.
Faults played an important role in migration and accumulation for oil and gas,for fracture caused by fault activity in improving the reservoir space and the prediction of structural reservoir. The fractal geometry is applied to study the fault systems of Es3 in Dongying depression. Fracture systems have the statistical self-similar characters and fractal characteristic in the non-scale range of 0. 5-8 km. The square of coordinate coefficients( R2) by least squares lines fitting are more than 0. 98 in log-log coordinate system of box counting number and the scale. Fractal dimension,can be used to quantify the complexity of the fracture distribution and with the increase of the fractal dimension,the development density of faults increased. With sedimentary facies and distribution of oil field,the distribution of oil field and the fractal dimension have a high degree of correlation. The areas near the fault across hydrocarbon source rocks are favorable to accumulate oil and gas. With sandstone,in the oilfield the fractal dimension of fracture system is between 0. 6 and 1. 3. With mudstone,the fractal dimension of fracture system is between 0. 8 and 1. 2. Based on this understanding,the structural reservoir is favorable to accumulate oil and gas. In some upper Es3,middle Es3,lower Es3 areas the structural reservoir is favorable to accumulate oil and gas.
The building process of the integral equation is given. The one dimensional PM above the rough sea surface and the composite ship target electromagnetic scattering characteristics of two-dimensional conductors are studied. Based on the method of moments block matrix and the information of the rough surface,the composite scattering coefficient is obtained,the effect of the wind speed,angle of incidence and the ship's draft depth on which the results is studied. Results analysis verifies the effectiveness of the proposed method.
This paper presents a method to calculate phased array antenna diffraction field which based on superposition principle and UTD. By calculating the diffraction field of each array element,the total diffracted field of the phased array antenna can be obtained. The method of this paper try to avoid a full-wave split,so it can be quick and effective.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)