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91.
Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) is an infectious disease associated with the respiratory system caused by the SARS-CoV-2 virus. The aim of this...  相似文献   
92.
Overtones of fruit wastes accumulate daily in the city of Chennai, India and there is an urgent need to develop, assess and use ecofriendly methods to dispose them. Presently an attempt has been made to study solid state biomethanation of fruit wastes using a laboratory scale anaerobic digester Fruit wastes containing 3%, 4% and 5% solids were used for experimentation. Daily and cumulative production of biogas produced during the study was recorded. Increase in nitrogen, phosphorus and potassium content in the feed was observed during the digestion. During the study the biogas generation increased with increase in total solids. While the gas generation was 0.006 m3/day/m3 of the reactor volume when the solid content was 3% the corresponding values for 4% and 5% solids were 0.27and 0.35 m3 respectively Varying TS 3% to 4% has no effect on fermentation stability and pH remained between 6.8 and 7.4, but an inhibition of methanogenic bacteria was observed for TS 5%. The overall performance of the reactor was depressed by changing feed concentration from 3% to 5%. Experiments with 4% initial solid contend was ideal for solid-state biomethanation.  相似文献   
93.
An underwater LNG release test was conducted to understand the phenomena that occur when LNG is released underwater and to determine the characteristic of the vapor emanating from the water surface. Another objective of the test was to determine if an LNG liquid pool formed on the water surface, spread and evaporated in a manner similar to that from an on-the-surface release of LNG.A pit of dimensions 10.06 m × 6.4 m and 1.22 m depth filled with water to 1.14 m depth was used. A vertically upward shooting LNG jet was released from a pipe of 2.54 cm diameter at a depth of 0.71 m below the water surface. LNG was released over 5.5-min duration, with a flow rate of 0.675 ± 0.223 L/s. The wind speed varied between 2 m/s and 4 m/s during the test.Data were collected as a function of time at a number of locations. These data included LNG flow rate, meteorological conditions, temperatures at a number of locations within the water column, and vapor temperatures and concentrations in air at different downwind locations and heights. Concentration measurements were made with instruments on poles located at 3.05 m, 6.1 m and 9.14 m from the downwind edge of the pit and at heights 0.46 m, 1.22 m, and 2.13 m. The phenomena occurring underwater were recorded with an underwater video camera. Water surface and in-air phenomena including the dispersion of the vapor emanating from the water surface were captured on three land-based video cameras.The lowest temperature recorded for the vapor emanating from the water surface was −1 °C indicating that the vapor emitted into air was buoyant. In general the maximum concentration observed at each instrument pole was progressively at higher and higher elevations as one traveled downwind, indicating that the vapor cloud was rising. These findings from the instrument recorded data were supported by the visual record showing the “white” cloud rising, more or less vertically, in air. No LNG pool was observed on the surface of water. Discussions are provided on the test findings and comparison with predictions from a previously published theoretical model.  相似文献   
94.
Civil coercion has its limitations, government regulation is only as effective as enforcement and investors base their estimates of firm value on information available from the firms themselves and from other sources. While voluntary disclosure is construed as being selective or incomplete, negative non-financial news such as details of fines imposed for environmental violation is reflected in lower stock prices for a short duration. This paper evaluates the persistence of goodwill capital for a sample of Indian companies from select industries, graded by their environmental performance. We conclude that investor concern differs across industries and that the correlation of environmental performance with firm valuation is, at best, weak and short-lived. Periodic scrutiny and announcement of industry environmental performance by appropriately equipped independent agencies could help coordinate and sustain stake-holder pressure on industry.  相似文献   
95.
Water table fluctuation (??h) can be used to rapidly assess changes in groundwater storage. But ??h gives acceptable results only if the point of observation is ideally located in the catchment of interest and gives average ??h of the area, a condition which is rarely met. However, if large numbers of observation wells are located within a basin (a catchment) the average ??h can be computed and used. But, a better way is to use points obtained by shallowest water level and deepest water levels to construct a wedge of water table fluctuation across the area of interest; the mean height of this wedge can be assumed to be the mean ??h in the area. And when there is only one observation well, the fact that water table is a subdued replica of the topography, is made use to construct the wedge of water table fluctuation. The results from some randomly selected observations in typical semi-arid, hard rock environment in Andhra Pradesh show that through this approach mean ??h can be effectively used to get change in groundwater storage in area. The mean recharge obtained in this study is in the order of 75 and mean draft is 58?mm/a, while mean recharge and draft obtained by conventional technique are 66 and 54?mm/a, respectively. The most likely specific yield around the middle reaches of a catchment ranges between 0.012 and 0.041 which is within the range given by Groundwater Estimation Committee of India for hard rocks.  相似文献   
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Tropical wood is attracting global attention in the light of dwindling sources of industrial raw material supplies, increasing concern for conservation and growing requirements for huge investments. This study examines the changing character of the world hardwood trade, and the factors that will affect future supply, demand and price. It also considers the likely implications of recent large-scale attempts to grow tropical species for pulp, developments in microtechnology and biotechnology on wood, and the proposed international commodity agreement for tropical timber. The study emphasizes the need for huge investments on a global scale in afforestation and research to fully realize the potential of the tropical biomass.  相似文献   
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The capital allowance structure for mining projects in developing countries affects the supply price of investment by determining the payback period, reinvestment and the timing of government receipts. Using the capital allowance structures of Sierra Leone, Tanzania, Zambia, Botswana, Papua New Guinea and Malaysia, the article develops a financial model and examines the effect of capital allowances on foreign investor and host government cash flows under various cost-price conditions. The study stresses the importance to governments of making accelerated depreciation a flexible tool to trade off against other elements in the fiscal package. From the government viewpoint, faster write-offs of capital are preferable to a tax holiday. The article places particular emphasis on evaluating the relationship between capital allowances, income tax and a rent resource tax.  相似文献   
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