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The physico-chemical and bacteriological parameters of the water in Taladanda canal and associated water-borne diseases,from which the dwellers have suffered,were studied,by using statistical method. Overuse and the addition of the wastes with sources from urbane industrial sectors,as well as the decrease in water level have caused the canal water quality declined drastically and subsequently led to extensive eutrophication and bacterial contamination. According to the water sample analytical results,the water is lightly acidic with the pH value of 4.5~6.7. The measured indexes,such as total dissolved solid (TDS),electrical conductivity (EC),total suspended solid (TSS),Mn,Zn,Al,Fe,Cu,Cr,and Hg etc,mostly have very high concentrations which are higher than permissible limit,indicating that the canal water is completely unsuitable for human consumption. Furthermore,the biological analysis shows that the total coliform (TC) is in the range of 45.9~30.2 in per 100 mL water in April,30.5~25.3/100 mL in July and 52.9~35.4/100 mL in December,respectively. Similarly,fecal coliform (FC) ranges from 12.8 to 10.1,10.5~7.5 and 13.1~6.4 per 100 mL water in the months of April,July and December respectively. As a result,people who use the water have suffered from different water-borne diseases. On the basis of disease data derived from hospital observations in a period of three years,there had been 4 284 people affected by different water-borne diseases from 2016 to 2018.  相似文献   
2.
The contamination of aquifers by fluoride and arsenic is a major cause of concern in several parts of India. A study has thus been conducted to evaluate the extent and severity of fluoride contamination and also its seasonal variability. Two blocks (Purulia-1 and Purulia-2) were considered for this purpose. Twenty groundwater samples (in each season) were collected from tube wells during the pre-monsoon and post-monsoon seasons. In addition to fluoride, groundwater samples were also analyzed for major cations, anions, and other trace elements. The concentration of fluoride shows significant seasonal variation and ranges between 0.94–2.52 and 0.25–1.43 mg/l during the pre-monsoon and post-monsoon seasons, respectively. In pre-monsoon season, more than 40% of the water samples show fluoride concentrations higher than the WHO limit. However, during the post-monsoon season, none of the groundwater sample shows fluoride concentrations higher than the WHO limit. Lesser concentration during the post-monsoon season is attributed to the dilution effect by the percolating rainwater, which has also been reflected in the form of a decrease in concentrations of other elements. The petrographic studies of the rock samples collected from the study area show that the rocks are mainly composed of plagioclase, orthoclase, and quartz with abundant biotite. The weathering and dissolution of biotite plays an important role in controlling the fluoride concentrations in the groundwater of the study area.  相似文献   
3.
The purpose of this study is to analyze and characterize recent landslide events in the Larji–Kullu Tectonic Window (LKTW), and to establish a relationship between the tectonic and lithologic characters of the terrain and the landslides activity. Using multispectral satellite image analysis with selected field investigation, a landslide occurrence database has been generated for the period between 1984 and 2015. To decipher the accelerated occurrences of landslides in the region, an integrated study is undertaken in the Kullu (also known as Kulu) valley of Beas River basin within the LKTW complex, to analyze the litho-structural and terrain slope interactions using morpho-tectonic parameters such as Topographic/Bedding Plane Interaction Angle (TOBIA) index, terrain surface roughness index and lithological competency analysis. A prominent clustering of landslides is observed in the north of Sainj River, contained within the tectonic window. Major sites of landslides are found to be located in the intensely fractured Manikaran Quartzite occurring within the core of the LKTW. The landslides are mostly associated with southern and southwestern-facing slopes and activations are pronounced in the ‘Orthoclinal’ slope class with gradient of 37°–48°. Thematic maps, e.g., geological, structural, geomorphological, slope and slope-aspect maps are generated and considered together to understand the morpho-tectonic scenario of the tectonic window. Observations from the above-stated thematic maps along with the occurrences of moderate magnitude earthquake epicenters helped to infer neotectonic movements along the Sainj River fault. Tectonic upliftment of the northern bank of the Sainj River along with increased precipitation through decades has resulted in recurrent landslides within the LKTW.  相似文献   
4.
Static analysis of stiffened shells has been carried out using an eight-noded isoparametric element for the shell and a three-noded curved beam element for the stiffener. A same displacement function is used for the shell and the stiffener elements. A modified technique has been followed to analyse the shell, which is an improvement over the degenerated shell concept. The stiffness matrix of the curved beam element is generated irrespective of its position and orientation within the shell element. The stiffness matrix of the stiffener is then transferred to all the nodes of the shell element. Numerical examples of stiffened shells with concentric and eccentric stiffeners have been analysed and the results presented together with those available in published literature.  相似文献   
5.
A study has been conducted in the heavily populated coastal areas of the Puri district (Odisha, India) with the aim to: (1) identify the factors that influence the major ion composition and concentrations of trace elements in groundwater; (2) determine the spatial distribution of the water-quality parameters and how they vary on a seasonal basis. To do this, groundwater samples were collected from 60 shallow tube wells located along the Puri coast during the pre-monsoon and post-monsoon seasons. Based on their TDS content, 52% of the collected groundwater samples were identified as being brackish-to-saline and unsuitable for drinking purposes in both the pre- and post-monsoon seasons. Significant concentrations of trace elements including Ba, Br, F, Fe, Mn, and Sr were detected in most of the samples. Iron concentrations were found to be higher than the WHO drinking water guideline value (0.3 mg/l) in 92% of the samples irrespective of seasons. Elevated Mn concentrations were observed in 37% and 40% of samples during the pre-monsoon and post-monsoon seasons, respectively. In addition, fluoride concentrations in excess of the WHO limit (1.5 mg/l) were found in 15% of samples during the pre-monsoon and 23% of samples during the post-monsoon season. The concentrations of major and trace elements show wide spatial and minor temporal variations. Large spatial and limited temporal variations in Cl and Na concentrations along with considerable Br and Sr concentrations in groundwater suggest that saltwater intrusion is the dominant process controlling groundwater quality in the study area, although other processes including ion exchange, the precipitation and dissolution of minerals, microbial activity, and the weathering of aquifer material also play roles to some extent in determining the spatial and seasonal distribution of the major and trace elements in coastal groundwater. Grouping of various water-quality parameters related to these processes by principal component analysis and their linking to one cluster in the hierarchical cluster analysis further supports the view that these processes control the groundwater chemistry in the coastal aquifer.  相似文献   
6.
Water depth estimation using optical remote sensing offers a reliable and efficient means of mapping coastal zones. Here, we aim to find a suitable model for fast and practical bathymetry of an estuary using Indian Remote Sensing Satellite (IRS) Linear Imaging Self Scanning Sensor (LISS-3) images. The study examines three different models; (1) least square regression model, (2) spectral band-ratio method and (3) multi-tidal bathymetry model. The findings are supported with in situ observed depth values and statistical estimates. Although the least square regression model has provided best results with root mean square error (RMSE) of 0.4 m, it requires a large number of observed data points for absolute depth estimation. Spectral band-ratio and multi-tidal model provides results with RMSEs 2.1 and 0.9 m, respectively. The present investigation demonstrates that multi-date imagery exploitation at disparate tide levels is the best estimation technique for recursive shallow water bathymetry where in situ observation is not possible.  相似文献   
7.
This paper presents the structural response of a fast and relatively small, composite materials catamaran to slamming loads. Finite element method is used to provide valuable information in order to optimise the design of the catamaran. The analysis is carried out using ANSYS 6.0 finite element software.The response of the structure to quasi-static slamming loads according to Det Norske Veritas High Speed and Light Craft crest landing and hollow landing rules [DNV, 1999] has been implemented and studied. An optimisation study for the structural response is carried out by changing the ply orientation in the vessel and suitable recommendations are made.  相似文献   
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