HIWAY—2模式对研究宁六公路（丁解直线段）汽车污染的应用   总被引：1，自引：0，他引：1  

曹文俊  朱汶 《南京气象学院学报》1991,14(2):203-210

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兰州河谷盆地近1万年的孢粉组合及气候变迁   总被引：7，自引：0，他引：7  

汪世兰  陈发虎 《冰川冻土》1991,13(4):307-314

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陕西洛南发现含碲黝铜矿   总被引：1，自引：0，他引：1  

曹恩魁 《矿物学报》1991,11(3):278-280,T001

陕西洛南发现的含碲黝铜矿产于含碲金石英脉中。呈不规则粒状,粒径0.1—0.4mm。实测维氏硬度为227kg/mm~2,相当摩氏硬度4.1。400—700nm波段反射率色散值为35.10—24.13％。颜色指数:R=24.87;x=0.3283;y=0.3130,λd=489;Pe=0.075。四个颗粒电子探针分析结果(％):Cu 41.70—42.39,平均42.133;Zn 5.09—5.59,平均5.345;Fe 0.02—0.30,平均0.145;Ag 0.00—0.10,平均0.033;Sb 14.93—16.79,平均16.023;As 6.09—7.57,平均6.655;S 23.91—24.55,平均24.228;Te 4.93—6.46平均5.645。根据分析结果的平均值计算矿物化学式:(Cu_(10.0593)Ag_(0.0052)_(10.0645)(Zn_(1.3353)Cu_(0.6232)Fe_(0.0415)_(2.00)(Sb_(2.1319)As_(1.4398)_(3.5717)(S_(12.2841)Te_(0.7159)_(13.00),简化式Cu_(10)Zn_2(Sb,As)_4(S,Te)_(13)  相似文献   

水泥土桩施工质量监测方法初探     

曹建春  朱大富 《岩土力学》1991,12(4):77-83

本文简单介绍利用静力触探、钻孔取样室内试验、动载测试、静载测试和控制灌浆量等方法来监测成桩质量,对实际施工有指导意义。  相似文献   

关中地区垂直形变场和应力场的特征     

王争良  曹建平 《地震工程学报》1992,14(4):69-74

本文利用关中盆地1972—1986年的4期大面积垂直形变资料,采用经典静态平差方法,求出该盆地相对于1972年的垂直位移量,并作出位移等值线图。据此讨论了近年来该盆地的垂直形变场的变化特征。结果表明,该地区现今的地壳垂直形变基本上继承了第四纪时期的特征,但在盆地西部有差异。本文将关中盆地简化为一个平面力学模型,采用有限元法反演关中盆地1976年、1980年和1986年相对于1972年的应力值,研究了该盆地的应力场分布特征。  相似文献   

Fault proximity surveys in coal using guided seismic waves—Numerical modelling     

S. A. Greenhalgh  S. Cao  I. M. Mason  D. R. Pant 《Pure and Applied Geophysics》1992,139(2):215-239

Guided seismic waves are generated at lateral discontinuities in coal seams as an integral part of the mechanics of scattering downgoing body waves from a surface energy source.Numerical and laboratory model studies undertaken for both thin and thick coal seam waveguides show that small faults generate recognizable diffraction patterns by convertingP andS waves into channel wave arrivals at in-seam geophones on a walkawayVSP profile.These results suggest that in-seam geophones can be used during subsequent surface reflection surveys so as to improve mine profitability by optimising longwall layout in faulted ground.  相似文献   

康定黄金坪金矿床原生晕分带特征及找矿意义   总被引：1，自引：0，他引：1  

曹志敏  李佑国 《矿物岩石》1992,12(2):53-60

黄金坪金矿床以自然金(银金矿)—多金属硫化物—碲金银系列矿物—碲化物以及石英、黄铁矿等矿物组合为特征;典型元素组合为Au(Ag)-Te-Cu-Pb-Zn-Ba-As。本文应用数理统计方法研究Ⅰ号矿体的原生晕及其分带特征,结果表明侧向分带(矿体向围岩)趋势As-Zn-Pb-Au-Ag-Te-Cu-Ba,垂向分带(由上至下)为Pb-Ag-Au-Zn-As-Te-Cu-Ba。该分带模式对于深部矿化预测与其它矿化带的远景评价具有现实意义。  相似文献   

Outlining a stepwise,multi-parameter debris flow monitoring and warning system: an example of application in Aizi Valley,China     

Ning-sheng Chen  Javed Iqbal Tanoli  Gui-sheng Hu  Feng-niang Wang  Cheng-lin Yang  Hai-tao Ding  Na He  Tao Wang 《山地科学学报》2016,13(9):1527-1543

In recent years, the increasing frequency of debris flow demands enhanced effectiveness and efficiency of warning systems. Effective warning systems are essential not only from an economic point of view but are also considered as a frontline approach to alleviate hazards. Currently, the key issues are the imbalance between the limited lifespan of equipment, the relatively long period between the recurrences of such hazards, and the wide range of critical rainfall that trigger these disasters. This paper attempts to provide a stepwise multi-parameter debris flow warning system after taking into account the shortcomings observed in other warning systems. The whole system is divided into five stages. Different warning levels can be issued based on the critical rainfall thresholds. Monitoring starts when early warning is issued and it continues with debris flow near warning, triggering warning, movement warning and hazard warning stages. For early warning, historical archives of earthquake and drought are used to choose a debris flow-susceptible site for further monitoring. Secondly, weather forecasts provide an alert of possible near warning. Hazardous precipitation, model calculation and debris flow initiation tests, pore pressure sensors and water content sensors are combined to check the critical rainfall and to publically announce a triggering warning. In the final two stages, equipment such as rainfall gauges, flow stage sensors, vibration sensors, low sound sensors and infrasound meters are used to assess movement processes and issue hazard warnings. In addition to these warnings, community-based knowledge and information is also obtained and discussed in detail. The proposed stepwise, multi-parameter debris flow monitoring and warning system has been applied in Aizi valley China which continuously monitors the debris flow activities.  相似文献   

A new method for the stability analysis of geosynthetic-reinforced slopes     

Fei Song  Ru-yi Chen  Li-qiu Ma  Geng-ren Cao 《山地科学学报》2016,13(11):2069-2078

This paper is concerned with the stability analysis of reinforced slopes. A new approach based on the limit equilibrium principle is proposed to evaluate the stability of the reinforced slopes. The effect of reinforcement is modeled as an equivalent restoring force acting the bottom of the slice and added into the general limit equilibrium (GLE) method. The equations of force and moment equilibrium of the slice are derived and corresponding iterative solution methods are provided. The new method can satisfy both the force and the moment equilibrium and be applicable to the critical failure surface of arbitrary form. Furthermore, the results predicted by the proposed method are compared with the calculation examples of other researchers and the centrifuge model test results to validate its correctness and effectiveness.  相似文献   

Molecular weight controllable degradation of <Emphasis Type="Italic">Laminaria japonica</Emphasis> polysaccharides and its antioxidant properties     

ZHA Shenghua  ZHAO Qingsheng  ZHAO Bing  OUYANG Jie  MO Jianling  CHEN Jinjin  CAO Lili  ZHANG Hong 《中国海洋大学学报(英文版)》2016,15(4):637-642

In this study, molecular weight controllable degradation of algal Laminaria japonica polysaccharides（LPS） was investigated by ultrasound combined with hydrogen peroxide. Three main factors, i.e., ultrasonic power（A）, ultrasonic time（B）, and H₂O₂ concentration（C） were chosen for optimizing parameters by employing three-factors, three-levels BBD. The influence of degradation on structure change and antioxidant activities was also investigated. A second-order polynomial equation including molecular weight（Y） of Laminaria japonica polysaccharides and each variable parameter, i.e., ultrasonic power（A）, ultrasonic time（B）, and H₂O₂ concentration（C）, was established: Y=20718.67-4273.13A-4000.38B-1438.75C+2333.25AB+1511.00AC+873.00BC+2838.29A² + 2490.79B²+873.04C². The equation regression coefficient value（R² = 0.969） indicated that this equation was valid. The value of the adjusted determination coefficient（adjusted R² = 0.914） also confirmed that the model was highly significant. The results of selected experimental degradation conditions matched with the predicted value. FT-IR spectra revealed that the structures of LPS before and after degradation were not significantly changed. Antioxidant activities of LPS revealed that low Mws possessed stronger inhibitory than the original polysaccharides. The scavenging effects on superoxide radicals was the highest when IC50 of crude LPS was 4.92 mg mL^-1 and IC50 of Mw 18.576 KDa was 1.02 mg mL^-1, which was fourfold higher than initial polysaccharide.  相似文献