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111.
为了研究黄土基底排土场破坏机理,对安太堡露天矿排土场基底黄土进行过载现象数值模拟研究。结果表明在排弃物不断回填的过程中,基底黄土逐渐出现塑性区域,最终由于基底软塑带图所承受载荷超过其极限值而使得自身强度急剧降低,从而产生破坏。并且通过二次回填的方法,可以防止塑性变形值增大过快而使得软塑带土过早的产生过载现象,这样更适合于排土场的规划。 相似文献
112.
在分析松软破碎带中巷道围岩的稳定性和支护影响因素的基础上,借助于注浆改善围岩特性并结合锚杆支护,通过现场实测、理论分析和FLAC数值模拟相结合的方法,确定了松软破碎带中的巷道围岩注浆深度、浆液比例和注浆孔间距等加固参数。研究结果对类似条件下的巷道的支护具有一定的指导意义。 相似文献
113.
塔里木克拉通盆地内古隆起及其找油气方向 总被引：1，自引：0，他引：1
《西安石油大学学报(自然科学版)》1997,(3)
塔里木盆地的古生代原型盆地是叠置于前寒武纪结晶变质岩系之上的克拉道盆地．盆地内发育了不同类型的古隆起，它们是：塔中稳定古隆起、塔北残余的古隆起、塔东残余古隆起、巴楚活动古隆起和塔南活动古隆起．这些不同类型的古隆起，具有不同的构造演化历史和不同的油气藏形成条件．古隆起蕴藏着丰富的油气资源，预测资源量占盆地内总资源量的近一半．在塔里木克拉通盆地寻找大中型油气田，首要的勘探目标是塔中稳定古隆起及其北斜直线和塔北残余古隆起及其南北斜坡，前者的勘探目的层是石炭系、奥陶系、志留系和泥盆系；后者的勘探目的层是石炭系、奥陶系、寒武系、震旦系、三叠系、侏罗系、白垩系和第三系。第二勘探目标是巴楚活动古隆起及其南斜坡，塔东残余古隆起及其西斜直线和塔南活动古隆起及其西南斜坡。它们的主要勘探目的层是石炭系、侏罗系、奥陶系、志留系和第三系． 相似文献
114.
王秀模 《重庆工商大学学报(自然科学版)》2011,(5)
建设两江新区离不开深入认识开发区的本质意义和发展方式。两江新区发展应在学习浦东新区和滨海新区的基础上,走内陆型的、创新性的新路,以科学发展观为主题,以转变发展方式为主线,以民生导向为重心,以面向西部聚集和幅射为目的。未来两江新区应站在历史和宏观的视角进一步明确新区定位,采取集约型、现代化的开发方式,将开放作为新区发展的特征。 相似文献
115.
内蒙古苏尼特右旗查干诺尔石炭系本巴图组火山岩地球化学特征及其地质意义 总被引：12，自引：0，他引：12
内蒙古查干诺尔地区石炭系本巴图组地层的火山岩,SiO2含量集中分布在48.20%～51.11%和64.66%～65.42%两个区间,分别属于玄武岩和英安岩,构成一套双峰式火山岩组合.其中基性火山岩具有枕状和块状构造,属于碱性玄武岩系列;英安岩的碱含量较高,属于钙碱性系列.基性火山岩中,枕状玄武岩轻稀土略亏损而重稀土略富... 相似文献
116.
A simple method is introduced in this study to better understand the growth process of hemihydrate phosphoric acid crystals. Using the proposed approach, large particles (>2 mm) can be produced reflecting the true state of the phosphoric acid particulate system. In contrast to previous studies, the principles for the crystallization curves were divided into two regions, based on the consumption of the phosphoric acid in solution. To maintain a constant crystal growth rate, a programmed cooling requirement was needed. In this reported study, the influence of a complexing agent (EDTA) on the crystallization process of phosphoric acid was also investigated. The results of this study showed that the presence of EDTA affected the metastable zone widths, as well as the kinetics of crystal growth. 相似文献
117.
Results of an investigation of in situ measurements of laser‐beam intensity Is and Im transmitted through aqueous ammonium dihydrogen phosphate (ADP) solutions saturated at 30 °C and water, respectively, and temperature Ts of solution and Tm of water during feeding of antisolvent acetone at different rates RA, using an indigenously designed experimental setup, are presented and discussed. It was found that: (1) for the measurement of MSZW, defined as the maximum volume fraction of acetone content Δxmax in the solution, obtained from temperature measurements are more reliable than transmitted laser‐beam intensity measurements for solutions, (2) two minima ΔTmin1 and ΔTmin2 associated with endothermic reactions, separated by a maximum ΔTmax due to exothermic reactions appear in the plots of temperature difference ΔT = Ts−Tm against acetone feeding time t, and (3) in the ΔT(t) plots there are time intervals Δt of constant rates RT of increase in ΔT of aqueous ADP solutions, and these values of RT increase linearly with acetone feeding time rate RA. The experimental data on the observed dependence of MSZW on antisolvent feeding rate RA, the appearance of minima ΔTmin1 and ΔTmin2 and maximum ΔTmax and their dependence on RA, and the relationship between RT and RA are discussed from consideration of processes of nucleation and growth of crystallites. 相似文献
118.
V. Mirsalimov A. Mustafayev 《ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik》2016,96(11):1339-1346
Influence of thermal source on growth of a curved crack in stretchable plane with regard to cohesive forces at the crack's end zone, is studied. It is assumed that the areas of action of tractions adjoin to the crack's tips. For inhibiting the growth of curvilinear crack, on the path of its extension in the vicinity of the crack's end, we form a zone of compressible stresses by heating the domain S by thermal source to temperature T0. The goal of local change of temperature is to delay or retardation of the crack growth. A boundary value problem on equilibrium of a bridged curvilinear crack with interfacial bonds under the action of external tensile loads, induced thermoelastic temperature field and tractions in the bonds preventing its opening is reduced to the system of nonlinear singular integral equations with a Cauchy‐type integral. Normal and tangential tractions in the bonds are found from the solution of this system. The condition of limit equilibrium of a curvilinear crack with interfacial bonds is formed with regard to criterion of limit stretching of the bonds. 相似文献
119.
We propose an amplitude spiral orthogonal zone plate (ASOZP) as a Cartesian-based spiral zone plate for generating variety of optical vortices. The presented model is made by overlapping closely a vertical spiral one-dimensional zone plate and a horizontal one. We demonstrate that the element produces diversity of focused vortices, in a way that the vorticity and number of the produced vortices could be easily manipulated. In addition, the generated vortices show rotation features in the vicinity of the focal plane. Furthermore, it is demonstrated that diffraction efficiency of the model is much more higher than the previously introduced Cartesian-based elements. We finally verify numerical results by experimental studies. 相似文献
120.
The aim of this work is to perform design and optimization of a cavitating device based on CFD simulation. A set of operational and geometrical parameters such as convergence angle, divergence angle, length of throat, and inlet pressure that can affect the hydrodynamic cavitation phenomenon generating in a Venturi are evaluated through CFD simulation and experimental approaches. Response surface methodology (RSM) was employed to achieve the optimum geometrical configuration. The CFD results show that the maximum cavitation zone in the Venturi can be obtained when half angle of the convergence section, throat length and half angle of the divergence section are 22.7°, 4 mm, and 6.5°, respectively. A maximum decolorization of 38.8% has been obtained using the designed Venturi at cavitation number (Cv) of 0.12. Additionally, the results were compared to that of various orifice plates. A decolorization of 26.2% using 33 holes orifice plate and 11.55% in one hole orifice plate approved the superiority of the designed Venturi. 相似文献