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991.
本文将混合井的概念引入滑坡治理的方案中,通过利用混合井排水降低滑坡体内的地下水位,提高滑坡的稳定性.文中提出了混合井排水在滑坡治理中的适用条件,并以宝鸡簸箕山滑坡为例,在软件Modelflow中建立三维模型进行数值模拟,提出了在滑坡治理中的混合井排水的优化方案. 相似文献
992.
Peng Wang Lei Liu Xichuan Liu Shuai Hu Shijun Zhao Wenming Ji Taichang Gao 《地球科学进展》1986,35(7):704-714
The accurate observation of the microphysical structure of cloud and precipitation plays an important role in understanding the formation of clouds and precipitation. In-situ measurement using measuring instruments carried by meteorological balloons is an effective way to obtain the microphysical properties of cloud and precipitation particles, which is a supplementary means for aircraft to observe cloud and precipitation particles. This observation method plays a more and more important role in in-situ measurement. According to the difference of the working principle of the existing balloon-borne cloud and precipitation particles probes, the detectors can be divided into particle impact-sampling sensors, particle imaging sensors, light-scattering sensors, light intensity attenuation sensors and charge measurement sensors. The working principles, key technologies and main advantages and disadvantages of typical instruments were summarized, and their applications to detailed cloud structure acquisition, cloud remote sensing method establishment, cloud and precipitation physical process research and parameterization, and scientific observation of thunderstorm clouds were briefly introduced. Finally, the development trend of balloon-borne cloud precipitation particle detectors was prospected, which will provide reference for related technical research and equipment development. 相似文献
993.
Two types of biotite isograd are defined in the low-grade metamorphism of the Wazuka area, a Ryoke metamorphic terrain in the Kii Peninsula, Japan. The first, BI1, is defined by the reaction of chlorite+K-feldspar= biotite+muscovite+quartz+H2O that took place in psammitic rocks, and the second, BI2, by the continuous reaction between muscovite, chlorite, biotite and quartz in pelitic rocks. The Fe/Mg ratios of the host rocks do not significantly affect the reactions. From the paragenesis of pelitic and psammitic metamorphic rocks, the following mineral zones were established for this low-pressure regional metamorphic terrain: chlorite, transitional, chlorite-biotite, biotite, and sillimanite. The celadonite content of muscovite solid solution in pelitic rocks decreases systematically with the grade of metamorphism from 38% in the chlorite zone to 11% in the biotite zone. Low pressure does not prohibit muscovite from showing the progressive change of composition, if only rocks with appropriate paragenesis are chosen. A qualitative phase diagram of the AKF system relevant to biotite formation suggests that the higher the pressure of metamorphism, the higher the celadonite content of muscovite at BI1, which is confirmed by comparing the muscovites from the Barrovian and Ryoke metamorphism. 相似文献
994.
Fu Hongtao Wang Jun Cai Yuanqiang Jin Jinqiang Dong Quanyang Hu Xiuqing Wang Peng Geng Xueyu Zhang Dikang 《Acta Geotechnica》2020,15(11):3183-3192
Acta Geotechnica - Project Oufei is the largest individual reclamation project in Wenzhou city, China, and the main infrastructure consists of seawalls, sluices and separation dikes. These... 相似文献
995.
北京市春夏季大气气溶胶的单颗粒分析表征 总被引:9,自引:0,他引:9
采集了北京市2000年春夏季大气气溶胶样品5个,采用扫描电镜X射线能谱技术分析大气气溶胶单颗粒约2500个。研究结果表明,沙尘期间,矿物尘是最主要的颗粒物种类,非沙尘期间,北京市大气气溶胶中主要检出矿物尘和含硫颗粒物。夏季随着颗粒物污染的加重,含硫颗粒物的数目百分数增加。是北京市大气颗粒物污染的重要特征。重点讨论了Ca-S颗粒、K-S颗粒和Ca-K-S颗粒三类典型含硫颗粒物的化学组成和粒径分布特征。数目可观的Ca-K-S颗粒以及其他硫酸盐颗粒的生成与相对湿度和云量等气象条件相关,这些颗粒物可能是云中过程的产物。减少SO2排放,减少含硫颗粒物,对于控制北京市的大气颗粒物浓度水平具有重要意义。 相似文献
996.
997.
LI Zongxing PENG Bo QI Kening LIU Dapeng MA Yinsheng ZHANG Wang HU Junjie WANG Jiaqi 《《地质学报》英文版》2022,96(1):386-399
In the Qaidam basin,Northwest China,karstic fissures and caves are developed in many places of the Lower Carboniferous Chengqianggou Fm.and Huaitoutala Fm.and the Upper Carboniferous Keluke Fm.,in which are found typical karstic marks.Several suites of transgressive carbonate rocks formed during the Late Paleozoic epoch are preserved as reservoir properties in the Qaidam basin,with paleokarst-related cave-fractured diagenetic structures,which provided the basis for cavefractured development.Carbonate and clastic samples covering or infilling caves and fractures in Carboniferous strata were collected in the eastern Qaidam basin to focus on petrological and geochemical analyses of karst and infilling materials.Based on this study of the Caledonian diagenetic sequence,and bitumen-infilled inclusion temperature and burial history,there existed a continuous atmospheric freshwater leaching process,which played a critical role in the construction of the Carboniferous supergene paleokarsts.Investigation and survey of the tectonic setting,plate paleolatitude and river development intensity also proves that there was abundant rainfall during the Indosinian period,after which the strata undergo a shallow burial process.Because Indosinian period is earlier than the key timing of hydrocarbon-generation of the Carboniferous source rocks,this kind of karst reservoir has potential significance for oil-gas resources in this area. 相似文献
998.
本文描述了11个铀酰矿物加热后的显微荧光特征,并对实验结果进行了初步探讨。随着温度的升高,其相对荧光强度均有不同程度的衰减直至猝灭,但衰减的速度和猝灭的温度是各不相同的。热至200℃时测量的荧光光谱和常温下的荧光光谱相比,不同矿物变化也各不相同。本文根据实验结果绘制了荧光和温度关系曲线及加热至200℃时的荧光光谱曲线。这种荧光变化可能与加热后矿物失水和晶体结构变化有关。对鉴定铀酰矿物具有重要的意义。 相似文献
999.
本文通过对福州市多种遥感卫星图片(包括美国专题制图卫星的TM三波段假彩色合成图片,时相为一九八八年四月十八日;美国地球资源卫星CCCT计算机处理,采用比例拉伸、矩阵变换、对数直方化、北东向增强、北西向增强等方法处理的不同图片),对福州市所处的地理位置、地形地貌特征、地震地质构造背景、水文地质条件,工程地质特征进行解释,结合野外地震地质调查,评判潜在的地震地质灾害。 相似文献
1000.
本文以同源岩浆演化序列的观点,探讨了炯隆寺-阿吉森多岩体的成因。研究结果表明,该岩体为印支晚期形成的同熔型花岗闪长岩-二长花岗岩,属于岛弧深成侵入的岩浆岩。 相似文献