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21.
The soil mass is subjected to temperature variation due to several human activities (viz. tanks storing heated fluids, buried cables and pipelines, air-conditioning ducts, disposal of nuclear and thermal power plant wastes etc.), which result in heat-induced migration of the moisture in it. Though several studies have been conducted in the past to investigate the mechanism of heat migration through the soil mass, a methodology for ‘real-time measurement of the variations in temperature, flux and moving moisture front, in tandem, with respect to space' has rarely been attempted. In this context, extensive laboratory investigations were conducted to measure real-time flux and temperature variations in the sandy soils, and the validation of results has been done by employing an equivalent electrical circuit programme, LTspice. Subsequently, a mathematical model PHITMDS (i.e. Prediction of Heat-Induced Temperature and Moisture Distribution in Soil) has been developed and its utility and efficacy, for predicting the depth-wise temperature and heat-induced moisture migration, due to evaporation, in terms of position of moving moisture front in the sandy soil has been critically discussed and demonstrated. 相似文献
22.
Rene PUTISKA Marian MARSCHALKO Isik YILMAZ Dominik NIEMIEC CHENG Xianfeng Ivan DOSTAL Jan KUBAC 《《地质学报》英文版》2021,95(5):1763-1770
This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaská near Banská Bystrica in Slovakia. The aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic material. Its maximum thickness is 3 m. Another specificific condition of the study area is its location in the built-up area, due to which the applicability of geophysical methods was limited. The article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill, which complicates the identification of cave spaces. The recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined. 相似文献
23.
基于国产高分辨率卫星影像和基础性地理国情监测数据,利用GIS技术分析了2013~2017年大渡口滨江老工业区搬迁改造实施的效果。结果表明,绿地面积呈增加趋势,增加量为1.28km^2,主要为天然草地;城市建设用地不断增加,用地性质日趋合理,其中工业用地、物流仓储用地和公共服务设施用地不断减少。空气质量总体较好,呈明显的季节性变化趋势。2017年空气质量优良天数为283d,说明搬迁改造工作成效显著。 相似文献
24.
试样经碱熔,盐酸提取的钛,在以盐酸、硫酸、磷酸组成的强酸性溶液体系中,利用铝片的强还原性,还原四价钛为三价钛。再用三价铁氧化三价钛为四价钛,过量的三价铁离子与硫氢酸根离子生成血红色络合物,根据此原理测定高含量钛。实验证明,溶液在此强酸性体系中,隔绝空气和控制时间的条件下,其含量范围在0.13%~100%内,测定结果准确度高。 相似文献
25.
Bacteria and bovine faecal matter were introduced into cultures of pathogenic free‐living amoebae, with chlorine or chlorine dioxide. The bacteria and faeces were to simulate natural conditions for a more exacting test of disinfectant demand when compared to axenic conditions. Both chlorine and chlorine dioxide were effective disinfectants under all conditions tested. Axenically and monoxenically cultured amoebae were used, the latter exerted a greater disinfectant demand. 相似文献
26.
27.
MARINE SOURCE ROCKS AND THEIR DEPOSITIONAL CONDITIONS OF MESOZOIC—CENOZOIC IN THE GAMBA—TINGRE BASIN,SOUTH TIBET:ORGANIC GEOCHEMICAL STUDY1 FuJiamo ,ShengGuoying ,XuJiayou,et.al.ApplicationofbiologicalmarkersintheassessmentofpaleoenvironmentsofChinesenon marinesediments[J] .OrganicGeochemistry ,1990 ,16 :76 9~ 779.
2 JenkynsHC .Cretaceousanoxicevents:fromcontinentstooceans[J] .JournaloftheGeologicalSociety ,1980 ,137:171~188.
… 相似文献
28.
A. Suryachandra Rao Y. Sadhuram V. V. Gopala Krishna 《Journal of Earth System Science》1995,104(4):607-611
We estimate, from the moisture budget the bulk aerodynamic coefficient for latent heat flux (C
e) during the monsoon season over the central Arabian Sea. The average value ofC
eunder active monsoon conditions was found to be 2.25 × 10−3 which is nearly 60% higher than those previously used. 相似文献
29.
综合物探探测煤矿水文地质条件 总被引:4,自引:0,他引:4
矿井突水是困扰煤矿安全生产的难题之一,查清采煤工作面的水文地质条件是有效防治水害,保证安全生产的前提。肥城矿务局生产实践证明了以直流电法、瑞利波法、瞬变电磁法等为主要手段的综合物探技术在探查采煤工作面和掘进迎头前方地质构造、含水层富水性及隐伏导水构造方面是一种简便、快捷、有效的手段。 相似文献
30.