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281.
Environmental Science and Pollution Research - Coronavirus refers to a group of widespread viruses. The name refers to the specific morphology of these viruses because their spikes look like a...  相似文献   
282.

Water scarcity necessitates a cost-effective and productive solution. This study focused to enhance the productivity of single slope solar still by incorporating the better weight of palm flower powder (micro-sized) in the basin and micro phase change material heat storage bed under the basin. In this aspect, the different quantity of palm powder weights such as 10, 30, 50, 70, 100, 120 and 150 g in the basin was experimentally examined. The absorber basin containing 50 g of palm powder has better productivity of 37.25%, whereas for 10, 30, 70, 100, 120 and 150 g, they were 11.85, 24.78, 36.8, 33.05, 10.25 and ? 20.22% respectively. The influence of palm powder with different weight% impregnated in the paraffin wax was analysed. The maximum thermal conductivity of 0.33 W/m K was obtained in the sample containing palm flower powder of 20 wt%. The experimental investigation was carried out with 50 g of micro-sized palm powder in the basin and thermal storage bed under the basin containing 20 wt% of micro phase change material (PCMPFP-SS) and conventional solar still (CSS). The overall distillate output of PCMPFP-SS was 4670 and 4250 mL/m2 on day 1 and day 2 respectively. On the other hand, the overall distillate output for CSS was 3030 and 2800 mL/m2 on day 1 and day 2. From the economic analysis, it was found that the cost per litre (CPL) of PCMPFP-SS and CSS was $ 0.025 and $ 0.032 respectively. Moreover, the payback period of PCMPFP-SS was lowered from 5.1 to 4.1 months compared to CSS.

  相似文献   
283.
Environmental Science and Pollution Research - Neurodegeneration is the loss of neuronal capacity and structure over time which causes neurodegenerative disorders like Alzheimer, amyotrophic...  相似文献   
284.
The removal of solubilized vat dye effluent using photo detoxification method was studied at various pH ranges. Experiments were carried out with synthetic effluent using total dye concentrations of 50, 100, 200, 300, and 350 mg/L. In sunlight photo oxidation, the original soluble vat dye is precipitated and can be filtered and reused by the textile industries. The effect of the different concentrations (1,000, 2,000, 3,000 mg/L) of total dissolved solids on the removal of vat dye was also carried out in the photo detoxification process. The efficiency of the dye removal was found to be 99 %.  相似文献   
285.
Fluoride concentration of groundwater reserves occurs in many places in the world. A critical area for such contamination in India is alluvial soil of the plain region, consisting of five blocks (Jhajjar, Bahadurgarh, Beri, Matanhail, and Sahalawas) of the Jhajjar District adjacent to the National Capital Territory of India, New Delhi. The purpose of this study was to assess the association between water fluoride levels and prevalence of dental fluorosis among school children of the Jhajjar District of Haryana, India. The fluoride content in underground drinking water sources was found to vary in villages. Hence, the villages were categorized as high-fluoride villages (1.52–4.0 mg F/l) and low/normal-fluoride villages (0.30–1.0 mg F/l). The source of dental fluorosis data was school-going children (7–15 years) showing different stages and types of fluorosis who were permanent resident of these villages. The fraction of dental fluorosis-affected children varied from 30% to 94.85% in the high-fluoride villages and from 8.80% to 28.20% in the low/normal-fluoride villages. The results of the present study revealed that there existed a significant positive correlation between fluoride concentration in drinking water and dental fluorosis in high-fluoride villages (r = 0.508; p < 0.001) and insignificant correlation in low-fluoride villages.  相似文献   
286.
The actinomycete strain LA-29 isolated from the gut contents of the fish, Mugil cephalus of the Vellar estuary showed excellent L-asparaginase activity The enzyme was purified 18-fold and the final recovery of protein was 1.9%, which exhibited an activity of 13.57 IU/mg protein. The partially purified L-asparaginase inhibited the growth of leukemia cells in male wistar rats. Average survival period of the rats was more in an optimum enzyme dose of 100 units and the survival period was less when the dosages were increased and at the same time the enzyme became less effective when the dosages were decreased. Higher survival of 17.2 days was recorded when 100 units of the enzyme was given in three intermittent doses (50/25/25 units) at the interval of 24 hr. Analysis of cell components of the strain LA-29 has revealed the wall type-I which is the characteristic of the genus Streptomyces. Further the morphological, physiological and biochemical features along with the micromorphological results obtained for the strain LA-29 were compared with that of the Streptomyces species found in Bergey's Manual of Determinative Bacteriology and the strain LA-29 has been tentatively identified as Streptomyces canus.  相似文献   
287.
A simple, sensitive, convenient and low cost spectrofluorometric technique for determination of quinalphos is described. Quinalphos is decomposed with sodium ethoxide. Resultant sodium diethyl thiophosphate (Na-DETP) is extracted with a cationic fluorescein as ion pair complex into 1-chloro-2-nitrobenzene. The fluorescence of the ion pair, fluorescein-DETP is measured at 530 nm after excitation at 490 nm. This technique is applicable for the determination of quinalphos in water, food grains and vegetable samples up to ng level with Amberlite XAD-4.  相似文献   
288.
Road ambient air pollution status along Dhanbad – Jharia road isstudied and presented in this article. The selection of this areais made considering the importance of the road in Dhanbad district and the nature of activities taking place along the road, which reflect that the portion of road upto Dhansar can be considered as having commercial areas on both sides and that from Dhansar to Jharia as having industrial areas on both sides.For the assessment of the ambient air quality along the road monitoring is done at the following five locations: Indian Schoolof Mines (ISM), main gate; Bankmore; Dhansar police check post; Dhansar opencast project agent office and a residential house beside the Rajapur opencast project. The location of ISM, maingate is specially chosen as this represents a commercial shoppingcomplexes and the situation can be compared with that at Bankmore. Monitoring of ambient air quality is done following thestandard procedure prescribed in IS: 5182. In addition the concentration of lead, zinc, copper, iron, manganese, cadmium metals in SPM is also monitored. The ambient air quality is monitored in the months of September and November 1999, respectively, to represent monsoon and winter seasons. The SPM concentration observed at all the five locations in the winterseason is more than the permissible limits for commercial andindustrial areas. However, in the monsoon season, the SPM concentration is higher than the permissible limit at the twocommercial locations, i.e., ISM gate and Bankmore, while it isless than the prescribed limit for industrial areas at the remaining three locations. At the ISM gate and Bankmore the SPM generation is mainly by vehicular traffic while at other three locations it was in addition due to mining and other activities.  相似文献   
289.
Bhattacharya A  Sarkar SK 《Ambio》2003,32(1):70-75
India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.  相似文献   
290.
Environmental Science and Pollution Research - The 2019 outbreak of corona virus disease began from Wuhan (China), transforming into a leading pandemic, posing an immense threat to the global...  相似文献   
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