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71.
乳砷铅铜石的发现与研究 总被引:2,自引:0,他引:2
乳砷铅铜石发现于1984年,在广西德保和平桂等矿区的硫化物型矿床的氧化带铁帽中.对该矿物的物理、化学和X射线粉晶分析、红外光谱分析以及差热分析等方面进行了测试研究,其结果与国外已知数据基本一致.矿物呈淡黄绿或深绿色,细粒状或葡萄状,硬度H=4,比重D=5.35,透明,二轴晶负光性,2V大,Ng=1.9817,Nm=1.9703,NP=1.9584.化学成分为PbO 35.19,CuO 30.64,As_2O_5 30.09,FeO 0.28,ZnO 0.05,H_2O 4.10(%).相应的化学分子式为Cu_(2.96)Pb_(1.21)(AsO_4)_(2.01)(OH)_(2.31)·0.59H_2O.X射线粉晶数据与JCPDS26~1410卡基本一政,衍射强线为3.14(10),3.24(8),2.92(8),2.55(8),2.74(7),2.49(7),2.27(7),4.51(6),4.94(5),2.66(4),1.902(4),1.817(4).计算的晶胞参数为a=10.236(?).b=5.904(?),C=14.213(?),β=106.39°,z=4,单斜晶系;空间群为A2/a.红外吸收光谱波数为3440、1640、870、820、775、465和1100、590、557(cm~(-1));差热分析吸收峰为580、773、812、889、898(℃). 相似文献
72.
To mitigate the impact of natural or man-made hazards on the services of an infrastructure facility, it is important to quantitatively assess its available capacity. For example, in a post-disaster scenario, critical infrastructure is likely to experience (i) excessive demand for the service of an infrastructure and/or (ii) compromised capacity because of damage to the infrastructure and the failure of infrastructure interdependencies. As the demand grows and nears the capacity limit of an infrastructure facility, a shortage of services required for the community’s recovery will occur. The development of mitigation strategies and an assessment of their effectiveness require a systematic approach. In this paper, a functional stress–strain principle for infrastructure facilities is proposed to quantitatively assess their serviceability in post-disaster scenarios. Functional stress in infrastructure management represents a service-related demand on an infrastructure facility, while strain indicates its coping capacity. The dynamic nature of infrastructure services will be considered depending on the relationship between demand and available capacity. The allowable range of functional stress is then defined, considering plastic and elastic patterns of responses of a facility during recovery to explore strain capacity variations. The proposed principle facilitates a systematic understanding of how infrastructure facilities can adapt themselves to growing stress and the maximum level of stress they can handle. The application of the proposed functional stress–strain principle is demonstrated through case studies of two infrastructure facilities in a post-earthquake scenario: a medical facility and a power facility. 相似文献
73.
郑毅 《吉林大学学报(地球科学版)》1996,(1)
垃圾产生于社会的每一个角落,垃圾也反映了人类生活的各个方面。可是,直至最近,社会依然极少理会垃圾中真正蕴藏着些什么,以及垃圾能够告诉我们些什么。1973年美国图森市亚利桑那大学威廉·拉舍基博士(WilliamLRathje)及其同事们所建立并发展的垃级计划,标志着一门新科学──垃圾学的兴起,即垃圾的系统研究、垃圾产生、运移、利用和处置的机理以及相关的社会经济和环境问题。美国和其它少数国家的垃圾学研究所揭示的各种事实、定律和原理,正划时代地碰击着现代社会、社会心理学、市场和许多其它领域,大量的城市固体废物不仅意味着自然资源的巨大浪费,而且垃圾处理,无论焚化或者填埋,都对环境构成了严重污染的威胁,尤其是对地下水资源。垃圾的管理、再循环和处置费用是昂贵的,而且总是受到错综复杂的社会和法律冲突的挑战,纽约和美国东部其它人口稠密地区所面临的严峻形势就是最好的例证,解决现今进退维谷的垃圾问题,需要包括技术的、社会的、环境的、经济的、政治的、法律的和公共教育在内的多方面协作。中国正经历着令人振奋的经济发展时期。预计以现在的国民经济发展速度,以及因巨量人口而导致的社会消费的急剧增长,在未来10~20年内,很有可能导致严重的 相似文献
74.
This paper presents flume and field observations of a bank-confined braided river. Morphological features, including plan form configuration, channel width, and main channel migration, were examined by a series of experiments. Repeated measurements of channel morphology, provided a basis to estimate the relationship between noncumulative frequency of bars and bar area. Additional results from the Dajia River, located in Central Western Taiwan, were presented to provide a reference data set for comparing the laboratory and field data. The results indicate that the relationship between bar length and width can be predicted by a simple best-fit power function relating to self-similarity characteristics. The Hurst index by Walsh and Hicks (2002) provides acceptable predictions of the bar length and width observed in the experiments and confirmed by the field investigations. Eexperimental and field results both show that large river width yields a uniform distribution of bar areas with the similar discharge, leading to a large value of exponent (β) in the model. The river width is confirmed to be a critical parameter in the main channel shift. A small increase in channel width likely increased rapidly the shift cycle. 相似文献
75.
Xue Song Wang Jun Jun Ren Hai Jie Lu Lei Zhu Fei Liu Qian Qian Zhang Juan Xie 《洁净——土壤、空气、水》2010,38(12):1131-1136
Magnetite nanoparticles were applied to remove Ni(II) from aqueous solutions as a function of pH, contact time, supporting electrolyte concentration, and analytical initial Ni(II) concentration. The highly crystalline nature of the magnetite structure with diameter of around 10 nm was characterized with transmission electron microscopy (TEM) and X‐ray diffractometry (XRD). The surface area was determined to be 115.3 m2/g. Surface chemical properties of magnetite at 25°C in aqueous suspensions were investigated. The point of zero charge (pHzpc) was found to be 7.33 and the intrinsic acidity constants (${\rm p}K_{{\rm a}1}^{{\rm s}} $ and ${\rm p}K_{{\rm a}2}^{{\rm s}} $ ) were found to be 9.3 and 5.9, respectively. The surface functional groups were investigated with Fourier transform‐infrared spectroscopy (FTIR) as well. Batch experiments were carried out to determine the adsorption kinetics and mechanism of Ni(II) by these magnetite nanoparticles. The adsorption process was found to be pH dependent. In NaCl solutions, Ni(II) adsorption increased with increasing ionic strength while in NaClO4 solutions, Ni(II) adsorption exhibited little dependence on the ionic strength of the solution. The adsorption process better followed the pseudo‐second order equation and Freundlich isotherm. 相似文献
76.
The No. 6 Coal-bed from the Heidaigou Mine, Jungar Coalfield, Inner Mongolia is a super-large Ga deposit. The dominant carrier of Ga is boehmite in coal. The study of coal facies may provide genetic enrichment information of Ga and its carrier (boehmite) in the Ga deposit. On the basis of study on coal petrology and mineralogy, it was found that the No. 6 Coal-bed from the Heidaigou Mine of Jungar was enriched in inertinites and the microlitho-types were dominated by clarodurite. The maceral morphological features and association indicate that the coal-bed was formed in a dry sedimentary environment or in a periodic dry sedimentary environment caused by the alternating variations of groundwater level. The optimum conditions for the enrichment of Ga and its particular carrier (boehmite) were dominated by four transitional conditions: (1) the upper delta plain which was the transitional zone between alluvial and lower delta plains, (2) the transitional zone between the dry and wet forest swamps, being slightly apt to the dry one, (3) the transitional tree density between the thick and loose ones, and (4) the low moor that was the transitional zone between two high moors during peat accumulation. 相似文献
77.
He Yi Wang Fei Mu Xingmin Guo Lanqin Gao Peng Zhao Guangju 《Theoretical and Applied Climatology》2017,129(1-2):645-654
Theoretical and Applied Climatology - We analyze the variability of sediment discharge and runoff in the Hekou–Longmen segment in the middle reaches of the Yellow River, China. Our analysis... 相似文献
78.
气候变化情景下澜沧江流域极端洪水事件研究 总被引:1,自引:0,他引:1
以澜沧江流域为研究对象,基于ISIMIP2b协议中提供的GFDL-ESM2M、HadGEM2-ES、IPSL-CM5A-LR、MIROC5这4种全球气候模式,通过4种模式的输出数据耦合VIC模型,分析4种模式在历史时期(1961—2005年)对洪峰洪量极值(年最大洪峰流量、3 d最大洪量)、极端洪水的模拟能力,比较RCR2.6和RCP6.0两种情景下未来时期(2021—2050年)年均径流量较基准期(1971—2000年)的变化情况,并结合P-III型分布曲线预估了澜沧江流域在两种情景下未来时期极端洪水的强度变化情况。结果表明:VIC模型在该流域能够较好地模拟极端洪水;HadGEM2-ES和MIROC5两种气候模式的输出数据在澜沧江流域有较好的径流模拟适用性;在RCP2.6情景下,澜沧江流域未来时期年均径流量没有明显变化,可能会有略微的增加,而在RCP6.0情景下,未来时期年均径流量有较大可能增加;澜沧江流域未来时期极端洪水较基准期,在RCP2.6情景下无明显变化,而在RCP6.0情景下,洪峰、洪量增加的可能性较大,极端洪水频率和强度也较大可能增加。 相似文献
79.
Kun LI Chaohui CHEN Hongrang HE Ru YANG Yi LI Yongqiang JIANG 《Journal of Meteorological Research》2021,35(3):490-504
Local breeding of growing modes(LBGM) is a method used to generate initial condition perturbation(ICP) for convection-permitting ensemble forecasts. Equal weights(EWs) are usually presumed in LBGM during the localization of ICP, without considering different contributions of the grid points within the local radius. To address this problem, Gaussian weights(GWs) are proposed in this study, which can accommodate the varied influences of the grids inside the local radius on the central grid through a Gaussian function. Specifically, two convection-permitting ensemble forecast experiments based on LBGM with GWs and EWs are compared and analyzed respectively for two squall line cases. The results showed that the use of the GWs intensified the local characteristics of the ICP and made the distribution of the ICP fields more flow-dependent. Kinetic energy spectrum of the ICP indicated that there could be more large-scale information in the ICP by using the GWs. In addition, mesoscale information also improved slightly. For forecast of nonprecipitation variables, GWs improved the relationship between the root-mean-square error and the spread and contributed to the forecasting accuracy of wind, temperature, geopotential height, and humidity. For the precipitation forecast, GWs simulated the precipitation structure successfully and provided better probability forecasting during the evolution of the two squall line processes than the EWs. 相似文献
80.
应用Windows操作系统的网络技术和自行开发的报警软件,解决了牡丹江地震台连续波形数据断记问题。本文详细介绍了解决方案和报警软件的安装及使用方法。 相似文献