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陈文焕 《矿物岩石地球化学通报》1993,(2)
“生物矿物学”一词是1973年马克·康尼尔提出的,它研究各种生物作用参与下产生的、具有一定组份的固结生成物,如骨骼、牙齿、软体动物中的耳石和外骨骼、珍珠、尿结石、胆结石、唾液结石等。它的研究对象很多方面与传统矿物学不同,首先是在其结构中总有有机物质存在,这些有机物与矿物部份是完全有规律的。它们的构造主要有放射状、同心环状、柱层状、枝叉状、交错层状等, 相似文献
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100多年以来,各领域的学者一直在研究着环境中的氟化物与人类健康的关系。大多数学者认为,摄入少量的氟有助于预防龋齿、强健骨骼,而长期摄入大剂量的氟会给健康带来不利的影响,包括氟斑牙、氟骨症,骨折机率增加;生育能力下降;尿结石机率增加;甲状腺机能下降;儿童智力下降。长期接触氟灰尘和气体,膀胱癌和呼吸系统疾病患病率增高。另据报道,摄入氟化钠杀虫剂和护牙用品会患急性氟中毒,严重者甚至死亡。自然环境中氟化物的分布非常不均一,主要是氟元素的地球化学特征所致。氟元素最先选择岩浆和热液释放地带富集,这就可以解释为什么正长岩、花岗类岩、火成岩、碱性火山岩和热液沉积岩的氟化物浓度一般比较高的原因。氟化物还常存在于沉积地层,该层包括来自原生岩的含氟化物矿物、富集氟化物的粘土、或者磷灰石。溶解的氟化物浓度一般受萤石（CaF2）的溶解度控制,因此,氟化物浓度高常常与软、碱性和钙含量不足的水体有关。尽管人们对氟化物的形成和其对健康的影响已经有很高的认识,但是,仍有很多氟化物与环境健康问题存在于第三世界国家,这些国家的居民几乎不能选择自己的饮用水和食物。即便是在发达国家,如果忽略了饮用水源之外的水源,那么,居民摄入的氟化物的含量也超过了推荐的剂量。 相似文献
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全国重要矿产和区域成矿规律研究进展综述 总被引：4，自引：0，他引：4
王登红 徐志刚 盛继福 朱明玉 徐珏 袁忠信 白鸽 屈文俊 李华芹 陈郑辉 王成辉 黄凡 张长青 王永磊 应立娟 李厚民 高兰 孙涛 付勇 李建康 武广 唐菊兴 丰成友 赵正 张大权 《地质学报》2014,88(12):2176-2191
对重要矿产开展全国性的资源潜力评价,是国情调查的重要组成部分,而开展重要矿产和区域成矿规律的研究,又是矿产资源潜力评价的基础性工作.自2006～2013年的8年间,通过对400多个典型矿床的野外调查,开展了典型矿床和区域成矿规律的全面研究,编制了成矿规律研究的技术要求,组织了全国性的技术培训,指导了大区和省级项目成矿规律研究工作,完成了大区和省级项目典型矿床和成矿规律研究成果的验收、汇总和综合,编制了全国单矿种(组)成矿规律相关专题图件,建立了相应的数据库,提出了一系列新认识、新技术和新方法,包括同位素定年的方法和成矿规律编图方法,为矿产资源潜力评价奠定了扎实了理论基础,有效地指导了潜力评价和地质找矿工作,培养了人才,锻炼了队伍,取得了良好的经济效益,显著地提升了我国成矿学的研究水平. 相似文献
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通过辽西某厂泥石流灾害的实地调查,阐述了泥石流发生的条件,介绍了泥石流危害,分析了泥石流的现状并预测了发展趋势,提出了防治措施。 相似文献
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自2000年以来,在提高了区域重力调查技术要求,更新了区域化探方法技术后,极大地提高了东北地区基础地质工作程度,发现了众多重力异常,圈定和推断了隐伏岩体、盆地和断裂构造.特别是区域化探,获得的地球化学异常更加丰富,真实地反映了地质规律,提供了较多的成矿远景区和找矿靶区,发现了众多矿产地.首次开展的多目标区域地球化学调查,查明了松辽平原土壤元素区域地球化学分布特征,证实了松辽平原土壤环境质量是优良的.这些成果为东北地区的地质工作提供了丰富的地球物理和地球化学基础信息. 相似文献
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异常查证是加速矿产普查的进程,是发现新矿产地的一条捷径。新一轮国土资源大调查对异常查证提出了新的更高的要求。本文总结了物探、化探异常查证找矿效果,分析了目前异常查证中存在的主要问题,强调了异常查证的重要性和必要性,提出了强化异常查证思考要点及主要途径。 相似文献
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针对川东北地区通南巴构造带海相碳酸盐岩储层的双孔特征,基于嘉二段、飞三段取芯及测试资料,利用岩心刻度测井的方法,确定储层下限参数,建立适合川东北地区通南巴构造带及邻近地区海相碳酸盐岩储层参数计算模型与评价标准.结果表明:川东北地区通南巴构造带碳酸盐岩储层下限值标准为孔隙度1.6%,裂缝孔隙度0.05%,含气饱和度50%.该成果为川东北地区通南巴构造带海相碳酸盐岩气藏内部参数分布描述与最终形成气藏三维数据体提供了可靠的资料,在实际生产中取得了良好的应用效果,为油田进一步勘探、开发和增产措施提供可靠的依据. 相似文献
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Kyungik Gil Haeyeon Rho Daeik Kim Michael K. Stenstrom 《Environmental Earth Sciences》2012,65(3):929-936
The Modified Bio-P module was evaluated in terms of the kinetic rate expression and engineering parameters, comparing the
measured data of full-scale plant with simulated data. To simulate step-feed BNR (Biological Nutrient Removal), the ASM3 (Activated
Sludge Model 3) with the EAWAG Bio-P Module (The Swiss Federal Institute for Environmental Science and Technology) and the
ASM3+Modified Bio-P module were used. The RMSEs (root mean square error) of the T-N (total nitrogen) concentration of the
effluent levels of measured and simulated examples were 2.29 for ASM3+Bio-P and 1.28 for ASM3+Modified Bio-P. In the case
of T-P (total phosphorus), the RMSEs were 0.28 for ASM3+Bio-P and 0.25 for ASM3+Modified Bio-P. The annual removal rates for
T-N were 0.77 for the measured, 0.69 for the Bio-P, and 0.74 for the Modified Bio-P samples, while the annual removal rates
for T-P were 0.64 for the measured, 0.72 for the Bio-P, and 0.60 for the Modified Bio-P cases. With simulated data, the Modified
Bio-P model was a better fit for the field data compared to Bio-P. The Modified Bio-P module reproduced the step-feed process
more effectively than the Bio-P module. 相似文献
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The influence of salts in the pore water in freezing soils is examined from the experimental viewpoint, using the differential scanning calorimetry technique for generation of multiple endotherms of the frozen test samples. The experimental values obtained for montmorillonite, kaolinite and grundite, are evaluated in terms of unfrozen water contents for the respective soils at various subfreezing temperatures for various concentrations of NaCl. Comparison of experimental values with theoretical predictions using a combined salt exclusion and diffuse double-layer model shows excellent quantitative agreement for the montmorillonite soil samples, but only qualitative agreement for the kaolinite and grundite soils. The reasons for this lie in the theoretical model requirement for interlamellar migration of water in soil freezing for suitable application of the diffuse double-layer part of the model. 相似文献
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This paper sets forth the theoretical background and basic numerical expressions for the incorporation of elastic-plastic constitutive equations for ductile rock into a finite element computer code. The derivation of an expression for the total strain rate is performed both for a total stress formulation and for a formulation that employs the concept of effective stress for inelastic behaviour. Specific expressions for the incremental strain rate are presented for the case of a porous material having a quadratic initial yield surface and observing the associated flow rule with a special hardening law for subsequent plastic deformation. A final section of the paper summarizes the expressions required to insert the quadratic yield surface model into a finite element code. 相似文献
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Landslides are one of the most damaging and threatening hazards associated with seismically induced slope movements. Estimations of support conditions for slope displacements are important for taking preventive measures to avoid landslide events in future. California's Division of Mines and Geology (DMG) procedure is utilised in the present paper for estimating the slope failure mechanism under seismic conditions. In this study, the DMG procedure has been explained and has also been incorporated in a Geographic Information System (GIS) using Arc-GIS software from Environmental Systems Research Institute. Further, it is utilised for establishing a seismically induced slope displacement map for the Skien municipality area of Telemark County in Norway. The motivation for selecting this site was the availability of geotechnical parameters for the site. Three different displacement maps have been produced for earthquake scenarios of magnitude 5, 6 and 7, respectively. The maximum displacement of 133 cm is estimated for earthquake scenario of magnitude 7. It is noticed that the sensitive areas for slope failure remain the same under different earthquake scenarios. A displacement tool based on the DMG procedure has been created in the Arc-tool box in Arc-GIS software. This tool minimises the efforts for inserting formulas for making raster displacement maps. By using the displacement tool one can generate final products like displacement maps automatically at high accuracy and in quick time. The prepared slope displacement maps of study area are used for landslide susceptibility zonation (LSZ) map preparation. The LSZ maps are useful for landslide hazard assessment and further can be utilised by planners, civil engineers and local administrators for town planning and policy-making. 相似文献
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《International Geology Review》2012,54(4):425-432
A review of the various geophysical methods used in prospecting for various mineral deposits, and recommendations for the improvement of known methods and the need for more precision. Methods of prospecting for various metals are discussed as well as means for raising their effective ness in exploration for ore deposits. The need for close cooperation between qualified members of geophysical departments and members of exploration organizations and the geophysical engineer is stressed.- -C. E. Sears, Jr. 相似文献
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X射线荧光光谱法测定土壤样品中碳氮硫氯等31种组分 总被引：3，自引：3，他引：3
利用新型的ZSX Primus Ⅱ型X射线荧光光谱仪采用粉末压片法直接测定土壤样品中的C、N、S、Cl等31种元素。各元素分析晶体为N采用RX45，C采用RX61，Na、Mg采用RX25，C1、S、P采用Ge，Si、Al采用PET，其余元素均采用LiF200。结果表明，方法的检出限、精密度和准确度对绝大多数元素而言，均可满足多目标地球化学调查样品分析的质量要求： 相似文献