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131.
We describe the microfabrication of 85Rb vapour cells using a glass-silicon anodic bonding technique and in situ chemical reaction between rubidium chloride and barium azide to produce Rb. Under controlled conditions, the pure metallic Rb drops and buffer gases were obtained in the cells with a few mm3 internal volumes during the cell sealing process. At an ambient temperature of 90 ℃ the optical absorption resonance of 85Rb D1 transition with proper broadening and the corresponding coherent population trapping (CPT) resonance, with a signal contrast of 1.5% and linewidth of about 1.7 kHz, have been detected. The sealing quality and the stability of the cells have also been demonstrated experimentally by using the helium leaking detection and the after-9-month optoelectronics measurement which shows a similar CPT signal as its original status. In addition, the physics package of chip-scale atomic clock (CSAC) based on the cell was realized. The measured frequency stability of the physics package can reach to 2.1×10-10 at one second when the cell was heated to 100 ℃ which proved that the cell has the quality to be used in portable and battery-operated devices.  相似文献   
132.
Variationally consistent homogenization is exploited for the analysis of transient uncoupled consolidation in micro‐heterogeneous porous solids, whereby the classical approach of first‐order homogenization for stationary problems is extended to transient problems. Homogenization is then carried out in the spatial domain on representative volume elements (RVE), which are introduced in quadrature points in standard fashion. Along with the classical averages, a higher‐order conservation quantity is obtained. An iterative FE2‐algorithm is devised for the case of nonlinear permeability and storage coefficients, and it is applied to pore pressure changes in asphalt‐concrete (particle composite). Various parametric studies are carried out, in particular, with respect to the influence of the ‘substructure length scale’ that is represented by the size of the RVE's. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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134.
Measurement of rock mass deformation with grouted coaxial antenna cables   总被引:4,自引:0,他引:4  
Summary Techniques presented herein show how reflected voltage pulses from coaxial antenna cable grouted in rock masses can be employed to quantify the type and magnitude of rock mass deformation. This measurement is similar to that obtained from a combined full profile extensometer (to measure local extension) and inclinometer (to measure local shearing). Rock mass movements deform the grouted cable, which locally changes cable capacitance and thereby the reflected wave form of the voltage pulse. Thus, by monitoring changes in these reflection signatures, it is possible to monitor rock mass deformation.This paper presents laboratory measurements necessary to quantitatively interpret the reflected voltage signatures. Cables were sheared and extended to correlate measured cable deformation with reflected voltage signals. Laboratory testing included development of grout mixtures with optimum properties for field installation and performance of a TDR (Time Domain Reflectometry) monitoring system. Finally, the interpretive techniques developed through laboratory measurements were applied to previously collected field data to extract hitherto unrealized information.  相似文献   
135.
广东省海岸表层沉积物中的重矿物近40种。含量较高的有钛铁矿、赤矿铁、磁铁矿、话石、电气石、黑云母和普通角闪石等。自生矿物主要为硬石膏、自然铜、黄铁矿及菱铁矿。这些矿物来自附近的母岩。根据物源性质不同,可将不同岸段重矿物区分为陆源矿物组合、近源-自生矿物组合和近源矿物组合三种:除物源控制外,重矿物含量、种类、形态特征及其在平面上的分布主要受沉积环境影响。据此,可将重矿物分布类型划分为河口型、海湾型和海岛型三类,且与上述不同矿物组合性质相对应。  相似文献   
136.
Based on the statistical outcomes relevant to elliptical isoseisms given in ref. [1], the average focal depth and rupture length of fault for earthquakes with different magnitudes or epicentral intensities occurring in East and West China are discussed. A set of intensity attenuation functions appropriated to point source (regarding focal distance as the distance parameter in the attenuation law) and the line source (regarding the shortest distance from the site to rupture line or the average distance from the site to both ends of the rupture line as the distance parameter) are proposed.  相似文献   
137.
河北东坪金矿区水泉沟岩体的地球化学特征   总被引:17,自引:0,他引:17       下载免费PDF全文
魏菊英  苏琪 《地质科学》1994,29(3):256-266
水泉沟岩体主要由二长岩构成。主要矿物是碱性长石和斜长石,它们的含量高达80%以上。石英不多见,暗色矿物含量少。副矿物主要是磁铁矿、石榴石、榍石和锆石。交代结构发育,蚀变现象普遍。主要化学组分和微量元素含量及δ18O值变化范围大。该二长岩体是由老片麻岩经热液碱交代作用而成。  相似文献   
138.
In the Yanliao area, the occurrence of the Nestoria-Keratestheria fauna and the Eoparacypris- Luanpingella-Darwinula assemblage in the Dabeigou Formation s.s., a Rb-Sr isochron age of 145.2 Ma for the Baiqi Formation and a complete stratigraphic sequence-all this proves that the Lycoptera-bearing bed overlies the Upper Jurassic. The Jehol fauna comprises the primitive Trigonioidids fauna, Eosestheria fauna, Lycoptera fauna et al., and their own laws of evolution expound that they belong to Cretaceous faunas. The associations of Eosestheria with Yanjiestheria, Lycoptera with Eosestheria, and Kuntulunia with Yanjiestheria as well as the occurrence of early angiosperms and sporo - pollen in the Fuxin Formation and its equivalents also demonstrate that the Lycoptera-bearing, bed should be assigned to the Cretaceous. The confirmation of the existence of Aucellina in the Jixi Group and the correlation of Trigonioidids and Cypridids with those in the equivalent strata of Japan and Western Europe have also been  相似文献   
139.
城市投资环境的评价模型及应用   总被引:21,自引:1,他引:21  
苏亚芳 《地理研究》1994,13(3):14-24
本文在对投资单元的量化,评价指标的选择及量化进行探讨的基础上,提出了专家得分和模糊评价二种投资评价模型,并以宁波市为例进行了应用.  相似文献   
140.
吉林省浑江市荒沟山区花岗岩成因类型探讨   总被引:4,自引:0,他引:4  
王速  邢树文 《吉林地质》1994,13(2):36-41
本文根据吉林省浑江市荒沟山区中生代花岗岩的岩石学、地球化学及同位素地质学研究,论述了该区花岗岩的成因类型,即老秃顶子岩体、梨树沟岩体、草山岩体均为同熔型。  相似文献   
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