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31.
The acoustic environment in urban areas has gained prominence in recent times due to rapid industrial and commercial development in metropolitan cities. Various attempts have been made to predict and model the trends in urban ambient noise levels using different statistical and dynamic models. The present study makes an attempt to examine the role of meteorological parameters affecting the ambient noise levels in Delhi. The results show significant improvement in overall noise scenario of Delhi since the introduction of compressed natural gas vehicles in public transport of Delhi. The noise level is significantly reduced by high vegetation cover as well as by low relative humidity over Delhi. The regression models developed for the present study clearly show the significant contribution of meteorological parameters in governing the ambient noise levels in Delhi.  相似文献   
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This study shows that glass powder of 200–300 mesh size range can be used as an absorbent for thin layer chromatography without adding any binder provided its uniformity is improved by a suitable thermal treatment. For this purpose TLC plates of the said mesh size range glass powder are heated thermally in a muffle furnace at a temperature of 650 °C for a period of 3 h.  相似文献   
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In recent years, increasing awareness of the environmental impact of heavy metals has prompted a demand for monitoring and decontaminating industrial wastes prior to discharging into natural water bodies. This paper describes the preparation and electrochemical application of carbon paste electrode modified with nanocellulosic fibers for the determination of cadmium and lead in water samples using anodic stripping voltammetry. First, cadmium and lead were adsorbed on the carbon paste electrode surface at open circuit potential, followed by anodic stripping voltammetric scan from -1 to 0 V. Different factors affecting sensitivity and precision of the electrode, including accumulating solvent, pH of the accumulating solvent, accumulation time, supporting electrolyte, and scan rate were investigated. The proposed method was also applied to the determination of Cd (II) and Pb (II) in the presence of other interfering metal ions and cetyl trimethyl ammonium bromide, sodium dodecyl sulfate, and Triton X-100 as a representative of cationic, anionic, and neutral surfactants. Linear calibration curves were obtained in the concentration ranges of 150–650 μg?L?1 and 80–300 μg?L?1, respectively, for cadmium and lead at an accumulated time of 10 min with limits of detection 88 and 33 μg?L?1. Optimized working conditions are defined as acetate buffer of pH?5 as accumulating solvent, hydrochloric acid as supporting electrolyte, and scan rate 50 mV/s. This technique does not use mercury and therefore has a positive environmental benefit. The method is reasonably sensitive and selective and has been successfully applied to the determination of trace amounts of Cd (II) and Pb (II) in water samples.  相似文献   
35.
In India, cane molasses–based distilleries are major production centers of ethanol. These industries release a dark brown colored effluent known as spent wash, which even after anaerobic treatment retains the color. The commonly used practices of treatment fail to remove the color and COD. A novel fungal consortium was developed for the treatment of this recalcitrant wastewater. The consortium was run on a bioreactor with undiluted distillery effluent for 40 days. In the first 14 days, 61.5% color and 65.4% COD removal was achieved. Further, the fungi were able to use wheat straw as carbon source as evidenced by scanning electron microscopy (SEM) while treating the distillery wastewater. It is expected that such a treatment step will lead to development of a treatment technology for distillery wastewater without the need for diluting it.  相似文献   
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ABSTRACT: The parameters of the extreme value type 1 distribution were estimated for 55 annual flood data sets by seven methods. These are the methods of (1) moments, (2) probability weighted moments, (3) mixed moments, (4) maximum likelihood estimation, (5) incomplete means, (6) principle of maximum entropy, and (7) least squares. The method of maximum likelihood estimation was found to be the best and the method of incomplete means the worst. The differences between the methods of principle of maximum entropy, probability weighted moments, moments, and least squares were only minor. The difference between these methods and the method of maximum likelihood was not pronounced.  相似文献   
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Mesozoic deposits of the former Gondwanaland are depauperate in early mammals, in general, and multituberculate mammals, in particular. Until now, the oldest multituberculate mammals known from the Gondwanan continents come from the Early Cretaceous of Morocco, NW Africa. Here, we report the presence of a new multituberculate mammal, Indobaatar zofiae gen. et sp. nov., from the Lower/Middle Jurassic Kota Formation, Pranhita-Godavari valley in peninsular India. This is the first record of a multituberculate from the Mesozoic rocks of India and possibly predates the oldest known multituberculates from Gondwanan continents. The new specimen, representing an upper premolar (P4), compares well with the upper premolar morphology of Eobaatariinae multituberculates known from the Early Cretaceous of Mongolia, China, England, and Spain. Together with the recent findings of cimolodontan multituberculates from the Early Cretaceous of Australia and Late Cretaceous of South America, the new discovery indicates a wide temporal and spatial distribution for multituberculate mammals in the former Gondwanaland.  相似文献   
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Environmental Science and Pollution Research - The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak began in late 2019 in Wuhan, China, and have since spread globally. Deep...  相似文献   
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The study investigated the origin, quality, composition, and trophic state of sedimentary organic matter (SOM) in core samples collected from three zones (Munambam, Vypin, Chettuva) of Central Kerala, India. The SOM exhibited enhanced levels for carbohydrate (CHO) followed by protein (PRT) and lipid (LPD); and phytopigment in the sediment followed the trend: Pheophytin (Pheo) > Carotenoid (carotend) > Chlorophyll-a (Chl-a) > Chlorophyll-b (Chl-b) > Chlorophyll-c (Chl-c). The low PRT: CHO ratio indicated a large amount of nonliving or aged organic matter in the sedimentary environment. Whereas the low Chl-a: Pheo ratio interprets the abundance of dead plant materials in the sediments. Correlation matrix showed strong association between organic matter and clay fraction of sediment. Furthermore, the strong interrelationships between biochemical components and chloropigments in all the zones suggested that SOM is strictly connected to phytodetritus deposition. Vypin zone near Vallarpadam Container Terminal revealed the presence of high biopolymeric carbon content. Besides, the PRT: CHO > 1 reflected the eutrophic condition at the same site but the low PRT: CHO ratio in the remaining stations displays the oligotrophic nature.  相似文献   
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