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1.
建设中老缅泰国际合作开发区营造景洪市立体开放口岸系统 总被引：1，自引：0，他引：1
本文论述了中老缅泰国际合作开发区建设是澜沧江—湄公河流域开发的优先启动区，是南南合作的新模式，对推动中南半岛次区域合作发挥着先导功能。景洪作为中国西南边境城市，在未来次区域合作中将升格为枢纽城市之一，因此，其开放度要不断扩大，在已具有的国家一类水运口岸基础上，要继续营造国家一类航空口岸、公路口岸，并在跨世纪建造昆明—曼谷铁路时，设置国家一类铁路口岸，同时在中缅２４０界桩两侧开辟新型的边境贸易旅游区，构筑景洪市全方位立体型开放系统。 相似文献
2.
在分析了当前测绘仪器管理存在问题的基础上，从仪器在实验室的管理体制、模式方面做了有益探讨和分析，提出了测绘仪器实行动态管理和开放使用的模式。 相似文献
3.
韩照信 《地球科学与环境学报》1994,(4)
架状硅酸盐矿物晶体结构为氧离子作开层堆积,阳离子充填空隙而形成.矿物晶胞参数与硅氧四面体的排列方式有关,和硅氧四面体的棱长l、对棱间距T_(?)、四面体的高T_h等几何要素有确定的函数关系. 相似文献
4.
Openings including their size, shape and distribution in rock play a significant role in the performance of rock related structures. The well-established knowledge in this area can contribute to the engineering practices, for example, underground space design, planning and optimisation in Civil and Mining Engineering and wellbore stability in Drilling Engineering, among others. Thus, understanding the failure mechanism of rock with openings is theoretically and practically meaningful. Laboratory testing on rock or rock-like materials with openings have been studied extensively in the literature, which, however, primarily focuses on the cracks/fractures. In this paper, a comprehensive numerical study on the effect of non-banded openings, i.e., circular, rectangular, and triangular opening, on the rock mechanical behaviour is performed using a hybrid continuum-discrete element method. It is revealed that the proposed simulation method can reproduce reasonably the crack initiation and propagation, and predict well the change of the mechanical behaviour due to the openings. In addition, the influence of the opening shape and opening ratio (=area of opening/specimen area) on the mechanical behaviour is also investigated. 相似文献
5.
靖学青 《云南地理环境研究》1997,9(1):18-22
随着时间的推移，沿边地区开放开发将不以人的意志为转移地发生形式上的转换，即边境国际贸易→边境出口加工企业→边境国际性区域经济合作，这种转换规律，是由利益机制驱动的。我国沿边地区在开放开发中出现的诸如沿边国际贸易不稳、发展缓慢等问题，就是因为沿边开放开发的形式转换，没有跟上边境经贸发展的步伐，沿边出口加工生产严重滞后的缘故，因此中国沿边地区应加快外向性产业实体建设，大力推进沿边开发形式的转换，以扭转当前的被动局面。 相似文献
6.
新疆与周边哈萨克斯坦等八个国家接壤,边界线长,可开发口岸多。在我国沿海、沿边开放总的发展战略的指导下,新疆利用优越的区位条件,初步形成了西拓中亚市场,南联巴基斯坦,北出蒙古多层次,全方位的立体边贸新格局,在沿边开放中,取得了可喜的成就。目前新疆正在抓住机遇,调整产业结构与地区布局,加强横向经济联合与协作,加强基础设施建设,为进一步扩大沿边开放创造更坚实的物质基础。 相似文献
7.
近20年来,尽管我国开发区对改革开放和经济发展做出了巨大贡献,但是开发区过多过滥,引发了许多社会问题。开发区的管理体制不健全,各级政府为了各种利益违规乱设乱批开发区,是造成“开发区热”的主要原因。要彻底清理整顿各类开发区,建立和完善开发区管理的长效机制,以保证开发区的健康有序发展。 相似文献
8.
Meter-scale subvertical strike-slip fault traces in the central Californian Sierra Nevada exhibit geometric complexities that significantly contribute to their mechanical behavior. Sections of faults that opened at depth channelized fluid flow, as evidenced by hydrothermal mineral infillings and alteration haloes. Thin sections show a variation in the style of ductile deformation of infill along the fault, with greater intensities of deformation along restraining bends. Orthorectified photomosaics of outcrops provide model geometries and parameter constraints used in a two-dimensional displacement discontinuity model incorporating a complementarity algorithm. Model results show that fault shape influences the distribution of opening, and consequently the spatial distribution of fluid conduits. Geometric irregularities are present at many scales, and sections of opening occur along both releasing and restraining bends. Model sensitivity tests focus on boundary conditions along the fault: frictional properties on closed sections and fluid pressure within sections of opening. The influence of the remote stress state varies along a non-planar fault, complicating the relationships between remote stresses, frictional properties, slip, and opening. Discontinuous sections of opening along model faults are similar in spatial distribution and aperture to the epidote infill assemblages observed in the field. 相似文献
9.
We present a theoretical model for diffusive daughter isotope loss in radiochronological systems with increasing temperature.
It complements previous thermochronological models, which focused on cooling, and allows for testing opening and resetting
of radiochronometers during heating. The opening and resetting temperatures are, respectively,
where R is the gas constant, E and D
0 are the activation energy and the pre-exponential factor of the Arrhenius law for diffusion of the daughter isotope, a the half-size of the system (radius for sphere and cylinder and half-thickness for plane sheet) and τ the heating time constant, related to the heating rate by
For opening and resetting thresholds corresponding to 1 and 99% loss of daughter isotope, respectively, the retention parameters
for sphere, cylinder and plane sheet geometries are A
op = 1.14 × 105, 5.07 × 104 and 1.27 × 104 and A
rs = 2.40, 1.37 and 0.561. According to this model, the opening and resetting temperatures are significantly different for most
radiochronometers and are, respectively, lower and higher than the closure temperature.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
10.
为进一步明确岩石破裂电磁辐射频率特征,基于岩石破裂电磁辐射是由岩石破裂时传播裂纹引起原子扰动产生的假说, 通过断裂力学理论中小范围屈服条件下张开位移法计算岩石破裂时的裂纹宽度,由单脉冲电磁辐射频率与裂纹宽度之间的关系,研究电磁辐射频率与岩石属性参数之间的关系,并给出了它们之间的关系表达式;单独讨论了不同属性参数对电磁辐射频率的影响.结果表明,电磁辐射频率随弹性模量增大而增大,随岩样尺寸和强度增大而减小,随泊松比的变化、岩石弹模的不同电磁辐射频率有变化;当弹模较小时,泊松比的影响也较小,而当弹模很大,即岩石刚度很大时,泊松比的增大会导致频率的增大;裂纹初始长度的变化受试件尺寸的影响,进而影响频率,当尺寸较大时,裂纹长度对频率影响较小,当尺寸较小时,频率随裂纹长度增大而增大.通过计算几种常见岩石破裂时电磁辐射频率值发现,岩石破裂时电磁辐射频率达到105 Hz量级,这与现有的实验结果相吻合. 相似文献