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21.
This study examines cointegration and Granger causality among global oil prices, precious metal (Gold, Platinum and Silver) prices and Indian Rupee–US Dollar exchange rate using daily data spanning from 2nd January 2009 to 30th December 2011. ARDL bounds tests indicate that the series are cointegrated. Toda–Yamamoto version of Granger causality has been employed to establish the causation amongst the variables. The study also examines generalized error variance decomposition of variables due to various shocks in the system. Such information provides insight into the transmission links between the global oil market and the Indian precious metals and foreign exchange market. These have the potential for significant impact in further research, portfolio management and central bank policy design.  相似文献   
22.
National Health and Nutrition Examination Survey (NHANES) uses two tobacco use surveillance questionnaires. One is administered during an at-home interview (HI) and the other, during an examination session at a mobile examination center (MEC). NHANES data for the years 1999–2012 were used to evaluate the consistency of responses to tobacco surveillance questions in HI and MEC interview. In addition, accuracy of self-reported smoking status was evaluated. Of those who reported to be daily cigarette smokers during HI, 18.7% reported to be either some-day smokers or nonsmokers during MEC interview. Of those who reported to be some-day cigarette smokers during HI, 22.1% reported to be daily smokers and 17.5% reported to be nonsmokers. Also, 4.1% of those who reported to be nonsmokers during HI reported to be either daily or some-day smokers during MEC interview. Using serum cotinine measurements taken during MEC interview, 27.1% were found to be smokers and 72.9% were found to be nonsmokers. In general, a moderate to high agreement, as measured by the κ statistic, was found between the self-reported responses to tobacco use questions during the home and MEC interviews as well as between smoking statuses based on self-reported and serum cotinine measurements.  相似文献   
23.
Hussainsagar Lake in the heart of Hyderabad City (India) receives toxic substances through five streams draining from a catchment area of 245 km2. Of particular interest are heavy metals received from urban runoff as well as municipal sewage and industrial effluents. Heavy metals entering the lake get adsorbed onto the suspended sediments, which eventually settle down in the bottom of the lake. In this study, fractionation of metal ions has been studied on the bed sediments of Hussainsagar Lake in order to determine the ecotoxic potential of metal ions. Comparison of sediments with average shale values indicated anthropogenic enrichment with copper, nickel, lead, cadmium, and zinc. The risk assessment code as applied to the present study reveals that 10–17% of manganese, 10–18% of nickel, 14–24% of chromium, 10–19% of lead, 21–30% of cadmium, and 18–28% of zinc exist in exchangeable fraction and, therefore, comes under medium risk category and may enter into food chain. The association of these metals with the exchangeable fraction may cause deleterious effects to aquatic life. The present database will help in formulating guidelines for carrying out dredging operations under restoration programs in the Hussainsagar Lake.  相似文献   
24.
The paper describes the effect of marble dust on plants in and around Vishwakarma Industrial Area (VKIA) Jaipur, Rajasthan (India). Trees species growing in and around VKIA area were selected and various morphological characteristics were studied such as leaf area dry weight ratio (LADWR), Dust retaining capacity (DRC) and Chlorophyll content. In the study the effects of marble dust on selected tree species was observed. LADWR was recorded maximunm 217.90 cm2 g(-1) dry wt. in Polyalthia longifolia in VKIA and minimum 98.74 cm2 g(-1) dry wt. in Ficus religiosa in Nindar whereas The DRC was observed maximum 178.51 mg cm(-2) in Azadirachta indica in VKIA as well as minimum recorded 66.41 mg cm(-2) in Thevetie pervvianain in Vidyadher Nagar. However the Total Chlorophyll Content was also determined and it was found maximum in Bougainvillea i.e. 2.949 mg g(-1) (fresh wt.) in VKIA whereas minimum for Nindar i.e. 0.784 mg g(-1) (fresh wt.) in Ficus religiosa.  相似文献   
25.
Biogas technology, besides supplying energy and manure, provides an excellent opportunity for mitigation of greenhouse gas (GHG) emission and reducing global warming through substituting firewood for cooking, kerosene for lighting and cooking and chemical fertilizers. A study was undertaken to calculate (1) global warming mitigation potential (GMP) and thereby earning carbon credit of a family size biogas plant in India, (2) GMP of the existing and target biogas plants in the country and (3) atmospheric pollution reduction by a family size biogas plant. The GMP of a family size biogas plant was 9.7 t CO(2) equiv. year( - 1) and with the current price of US $10 t( - 1) CO(2) equiv., carbon credit of US $97 year( - 1) could be earned from such reduction in greenhouse gas emission under the clean development mechanism (CDM). A family size biogas plant substitutes 316 L of kerosene, 5,535 kg firewood and 4,400 kg cattle dung cake as fuels which will reduce emissions of NOx, SO(2), CO and volatile organic compounds to the atmosphere by 16.4, 11.3, 987.0 and 69.7 kg year( - 1), respectively. Presently 3.83 million biogas plants are operating in the country, which can mitigate global warming by 37 Mt CO(2) equiv. year( - 1). Government of India has a target of installing 12.34 million biogas plants by 2010. This target has a GMP of 120 Mt CO(2) equiv. year( - 1) and US $1,197 million as carbon credit under the CDM. However, if all the collectible cattle dung (225 Mt) produced in the country is used, 51.2 million family size biogas plants can be supported which will have a GMP of 496 Mt of CO(2) equiv. year( - 1) and can earn US $4,968 million as carbon credit. The reduction in global warming should encourage policy makers to promote biogas technology to combat climate change and integration of carbon revenues will help the farmers to develop biogas as a profitable activity.  相似文献   
26.
A number of low cost waste sorbent have been used for removal of heavy metals, however, few studies have been carried out on the sorption process on riverbed sediments in their natural state of occurrence. Stream sediments adsorb certain solutes from streams, thereby significantly changing the solute composition, but little is known about quantitatively describing sorption phenomena and rates of these processes. In the present investigation, sorption of lead ions on river bed sediments of river Hindon, a tributary of river Yamuna, India has been studied to demonstrate the role of bed sediments in controlling metal pollution. The effect of various operating variables, viz., initial concentration, solution pH, sediment dose, contact time and particle size has been studied. The sorption of lead ions increased with respect to pH and sorbent dose and decreased with sorbent particle size. Two important geochemical phases, iron and manganese oxide, also play important role in the sorption process. The sorption data were analysed using Langmuir and Freundlich isotherm models to determine the mechanistic parameters related to the sorption process. Further, although lead ions have more affinity for the fine fraction of the sediment, but the overall contribution of coarser fraction to sorption is more as compared to clay and silt fraction. The kinetic data suggest that the sorption of lead on bed sediments is an endothermic process, which is spontaneous at low temperature. The uptake of lead is controlled by both bulk and intraparticle diffusion mechanism.  相似文献   
27.
A case study of landfill liquids addition using small diameter (5 cm) vertical wells is reported. More than 25,000 m3 of leachate was added via 134 vertical wells installed 3 m, 12 m, and 18 m deep over five years in a landfill in Florida, US. Liquids addition performance (flow rate per unit screen length per unit liquid head) ranged from 5.6 × 10?8 to 3.6 × 10?6 m3 s?1 per m screen length per m liquid head. The estimated radial hydraulic conductivity ranged from 3.5 × 10?6 to 4.2 × 10?4 m s?1. The extent of lateral moisture movement ranged from 8 to 10 m based on the responses of moisture sensors installed around vertical well clusters, and surface seeps were found to limit the achievable liquids addition rates, despite the use of concrete collars under a pressurized liquids addition scenario. The average moisture content before (51 samples) and after (272 samples) the recirculation experiments were 23% (wet weight basis) and 45% (wet weight basis), respectively, and biochemical methane potential measurements of excavated waste indicated significant (p < 0.025) decomposition.  相似文献   
28.
The drinking, borewell and sewage water in the Sanmugasikamani Nadar (S.N) street, Naivatti Nadar (N.N) street and Thiruthangal area of Sivakasi has been studied. The various constituents monitored include the physicochemical characters like pH, total solids, total dissolved solids, total suspended solids; chemical parameters like total alkalinity acidity free CO2, dissolved oxygen, total hardness, calcium, magnesium, chloride, salinity and bacterial parameters like standard plate count (SPC), total coliform count (TCC), faecal coliform count (FCC), faecal streptococcal count (FSC). Most of the physicochemical characters of drinking and borewell water were within the ISI permissible level. However in water samples from all the sites, bacterial count exceeded the recommended permissible level of WHO. Introduction of sewage into the drinking and borewell water was the main reason for the bacterial contamination. The boiling of water is therefore advisable before consumption. The physicochemical and bacterial characters of the sewage water were unworthy. The sewage water recycling was necessary to minimize the water born diseases.  相似文献   
29.
30.
Microbial polyhydroxyalkonate such as homopolyester of poly(3-hydroxybutyrate) (PHB) was produced from cheese whey by Bacillus megaterium NCIM 5472. Due to their numerous potential industrial applications, the focus was given to competently enhance the amount of PHB produced. The amount of PHB produced from whole cheese whey, and ultrafiltered cheese whey was first compared, and after observing a rise in PHB production by using ultrafiltered cheese whey, cheese whey permeate was chosen for further analysis. The presence of PHB was then confirmed by GCMS. Since the main aim of the study was to increase the amount of PHB produced through batch fermentation, various process parameters like time, pH, C/N ratio, etc. were optimized. After optimization, it was found that B. megaterium NCIM 5472 was capable of accumulating 75.5% of PHB of its dry weight and a PHB yield of 8.29 g/L. The chemical structure of the polymer was further analyzed by using FTIR and NMR spectroscopy methods. Also, the physical and thermal properties were studied by using Differential scanning calorimetry and Thermogravimetric analysis. It was found that the polymer produced had excellent thermal stability, thus allowing the possibility to exploit its properties for industrial purposes such as adhesives, packaging materials, etc.  相似文献   
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