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11.
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   
12.
Propargite, recently introduced in India, is an effective acaricide on a large number of crops most of which are consumed by human beings directly or after processing. Therefore, it has become important to check the dissipation behavior of propargite in edible raw commodities, processed products and in the environment. In the present study, dissipation of residue of this acaricide in soil, apple fruit and tea (green tea leaves, manufactured tea, infusion and spent leaves) was studied. Analysis was carried out using high performance-liquid chromatography with UV detection system. The dissipation rate was found to vary with the nature of studied crop/sample. In soil, half-life ranged from 43 to 45 days, while in plant matrices (tea and apple) it ranged 1.66-2.61 days. The percent transfer of propargite residue from manufactured tea to infusion was 23.60-40.00; however, 35.71-53.20% of the residues remained stuck to the spent leaves.  相似文献   
13.
Earth air tunnel heat exchanger (EATHE) is a promising passive technique to provide thermal comfort condition in buildings. EATHE system uses undisturbed temperature of the ground for heating/cooling of air. Despite the several advantages, this technique has not become much popular owing to its high capital cost (mainly pipe cost and trench excavation cost) and large land area requirements. The primary objective of this study is to present a comprehensive review of different EATHE pipe layouts, pipe properties and positioning of the pipe with their advantages and limitations. It is observed that the ring pipe layout is the most cost-effective pipe-layout for small size EATHE system because it saves excavation cost by using a trench of the existing foundation of the building. However, Grid pipe-layout is an ideal layout for a large size EATHE system. Multi-layer pipe layouts should be used to reduce the land area requirement significantly. Moreover, EATHE system can be installed beneath the building (under building foot-print) to eliminate extra land area requirement for the installation of EATHE system. This review article shows that the Initial capital cost and land area requirement for the EATHE system can be substantially reduced by using appropriate pipe layout. It can be concluded that if EATHE system is installed with proper design strategies, it will be a clean and cost-effective method for building heating/cooling with significant power savings.  相似文献   
14.
This study investigates the safe carrying load limit in relation to gender of workers in the sugar industry. A total of 632 workers (male and female) were interviewed following a physiological and psycho-physiological methodology. All of these workers were in the age groups of 21–30, 31–40 and ≥41 years. In this study, for the physiological methodology, both field and laboratory data were collected, which included heart rate, heart rate variability, energy expenditure and maximum rate of oxygen consumption. Information regarding hemoglobin content, weight, age, lean body weight, etc., was recorded to know the physical health of the workers. In the psycho-physiological evaluation, load-carrying limits were determined by the psychophysical rating of the load by workers from the selected age groups. By considering the physiological stresses and psycho-physiological evaluation, the safe carrying load limit was determined in head and back mode for male and female workers as per their age groups.  相似文献   
15.
16.
Females of the moth Utetheisa ornatrix (Lepidoptera: Arctiidae) mate preferentially with males that excel in three quantitatively correlated attributes: body mass, systemic content of defensive pyrrolizidine alkaloid (derived from the larval diet), and glandular content of the courtship pheromone hydroxydanaidal (derived from the alkaloid). By so choosing, the females obtain direct phenotypic benefits (alkaloid and nutrient received with the spermatophore), and indirect genetic benefits (genes for large size, a heritable trait). We asked whether the female appraises the courting male on the basis of all three attributes, or whether, as had been postulated, she does so on the basis of the intensity of the pheromonal scent alone. We present data indicating that male possession of hydroxydanaidal is indeed the sole criterion of choice. Females fail to differentiate between males that differ in body mass or alkaloid content if the males lack hydroxydanaidal, but choose between males that are size-matched and alkaloid-free if one of the males has been experimentally endowed with hydroxydanaidal. We show moreover that females are able to differentiate between males that contain unequal quantities of hydroxydanaidal. Females abide by these criteria whether or not they themselves contain alkaloid. Their choice was also unaffected by whether they were confined singly with 2 males in small mating chambers, or were in groups of 10 with 20 males in large flight cages.  相似文献   
17.
A statistical methodology formulated for defining background or baseline levels of constituents of concern in groundwater is presented. The methodology was developed for the case where prior delineation of unimpacted areas is not possible because of site history and a large set of groundwater monitoring measurements exists. Consideration was given to spatial and temporal trends, outliers, and final segregation of wells into impacted or unimpacted categories to develop probability distributions and summary statistics for each constituent evaluated. The formulated approaches were applied to groundwater monitoring data for the U.S. Department of Energy Savannah River Site facility, and results for four representative constituents (aluminum, arsenic, mercury, and tritium) are discussed.  相似文献   
18.
Purpose. In lower-middle-income countries, most of the work is performed manually using non-ergonomic hand tools which results in work-related health problems. Using hand tools designed in line with ergonomic principles may play an important role in reducing work-related health concerns significantly. Methods. Scientific databases (PubMed, EBSCOhost) and e-publishers were searched for articles from 1985 to 2015 using the following keywords: ‘hand tool’, ‘ergonomics’, ‘usability’ and ‘design’. After applying selection criteria to 614 articles, 58 articles related to the physical design of hand tools were selected. Results. Seventeen articles were related to hand tool improvement in the manufacturing sector. Musculoskeletal disorders were found to be the most frequently occurring work-related health problems. Most of the articles focused on product and qualitative variables for improvement in hand tools, while few articles considered human and task variables. Conclusions. Literature shows that hand tool improvement studies have been given less importance in low-income and lower-middle-income countries. However, some work of significance is reported in the agriculture sectors of these countries. Hence, it is concluded that ergonomic intervention in hand tools is much needed for those industries which employ traditional methods of working.  相似文献   
19.
The water sources in developing countries are usually contaminated with the members of enterobacteriaceae leading to gastrointestinal infections. There has been an increasing consumption of antibiotics during last decade in India. The development of multiple antibiotic resistance and heavy metal tolerance among waterborne bacteria has been coexisting traits. Keeping above features in view, 51 waterborne isolates of Escherichia coli O157:H7 have been characterized in the present study. The disk diffusion test for antibiotic sensitivity assay revealed that all the isolates were resistant to at least one or more antibiotics. Cephalosporins were least effective, while fluoroquinolones and aminoglycosides were most effective antibiotics. The isolates shared resistance pattern similarities regardless of their sources. The isolates were subjected to test maximum tolerance concentration of heavy metals such as arsenic, lead, chromium and mercury. About 98% isolates tolerated arsenic at 250 μg ml?1 or various above concentrations. Mercury >25 μg ml?1 was not tolerated by more than 90% isolates. In dug well, a commonly used water source in rural India, the isolates exhibited multiple antibiotic resistance index of 0.68 indicating it as high risk contaminating source. PCR–RFLP of 16S rDNA distinguished isolates into four groups with the smallest group represented by 3 isolates. Three isolates belonged to different sources but shared all the features of biochemical, serological, multiple antibiotic resistance and heavy metal tolerance test. 16S rDNA sequence analysis showed that the three selected isolates were closely related to each other. Based on the microbial and molecular findings, the study recommends to follow social cognitive theory to alter the behavior of the local communities for sustainable use of water resources.  相似文献   
20.
In this work, we examined water-quality assessment in relation to fish assemblage of Gomti River, a large tributary of the Ganges River basin in northern India. Principal component analysis was performed for 18 environmental variables which produced three axes that cumulatively explained 60.23% of the environmental variation in sites. Fifteen variables (fine substrate fine gravel, coarse gravel, cobble, sand substrate water flow, conductivity, TDS, total hardness, temperature, dissolved oxygen, pH, and overhanging vegetation) had high loadings on at least one of the principal component axes interpreted. The canonical correspondence analysis was used to establish the relationship between important fish species and environmental variables. Species were distributed within four groups with respect to the significant habitat characteristics. The Pearson correlation coefficient was calculated between the water-quality parameters. We concluded that the level of species richness is mostly dependent on abiotic factors like temperature, dissolved oxygen, TDS, conductivity, depth, pH, and water current in the Gomti River, of the Ganges basin.  相似文献   
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