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Vanerkar AP Kulkarni NP Zade PD Kamavisdar AS 《Environmental monitoring and assessment》2008,143(1-3):239-245
As mining operations get mechanized, the rate of profit generation increases and so do the rate of occupational hazards. This study deals with one such hazard - occupational vibration. The present study was carried out to determine the whole body vibration (WBV) exposure of the heavy earth moving machinery (HEMM) operators in two types of metalliferous mines in India, when they were engaged in the mining activity. Cross-comparison was done of the vibration dose value (VDV) for HEMM operators as well as each type of mine. The VDV for the shovel operator in bauxite mine was observed to be 13.53 +/- 5.63 m/s(7/4) with 25% of the readings higher than the prescribed limit whereas in iron ore mine VDV for dumper operator was 10.81 +/- 3.44 m/s(7/4) with 14.62% readings on the higher side. Cross-comparison of the VDV values for bauxite and iron ore mines revealed that it was 9.57 +/- 4.93 and 8.21 +/- 5.12 m/s(7/4) with 21.28 and 14.95% of the readings on the higher side respectively. The Student's t test level was found to be insignificant for both type of mines, indicating that the WBV exposure is not dependent on the type of mine but is dependent on the working condition and type of HEMM in operation. 相似文献
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Chetan M. Zade Umesh D. Pete Smita S. Patil Jitendra D. Bhosale Chakradhar D. Hadole Meghraj S. Kadam 《Journal of environmental science and health. Part. B》2013,48(2):136-143
Insect-growth regulators (IGRs) have been receiving foremost attention as potential means of selective insect control. Benzoyl phenyl urea (BPU) is a well-known IGR having chitin synthesis inhibitor activity. Mimics of BPU have been synthesized by suitable derivatization of a naturally occurring monoterpenoid, thymol (2-isopropyl-5-methyl phenol) to form a = series of substituted benzoyl thymyl thioureas (BTTUs) [IVa-f] and benzoyl thymyl ureas (BTUs) [Va-f]. The synthesized compounds have been characterized by 1H and 13C NMR, LC-MS and elemental analysis. These derivatives have been screened for their effect on total haemocyte count of Dysdercus koenigii. It has been observed that the introduction of substituted benzoyl thiourea and urea linkage into a thymol ring via an amino group results in higher activity than the parent compound thymol and a comparable pattern of results with the standard insect-growth regulators, Penfluron. Urea [Va-f] compounds exhibited greater effect on Total Haemocyte Count (THC) than thiourea [IVa-f]. Fluoro substitution enhanced the effect on THC more than chloro substituted compounds, while ortho-substitution resulted in a better effect than para-substitution. The results described in this paper are promising and provide new array of synthetic chemicals that may be utilized as insect growth regulators. 相似文献
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Nagpur City located in semiarid area of central India is a fast-growing industrial centre. In recent years, rapid development
has created an increased demand for drinking water, which is increasingly being fulfilled by groundwater abstraction. The
present study was undertaken to assess major ion chemistry of shallow groundwater to understand geochemical evolution of groundwater
and water quality for promoting sustainable development and effective management of groundwater resources. A total of 47 water
samples were collected from shallow aquifer of selected parts of the city and the water chemistry of various ions viz. Ca2 + , Mg2 + , Na + , K + , CO3 2-_{3}^{\ \, 2-}, HCO3 -_{3}^{\ \, -}, Cl − , SO4 2-_{4}^{\ \,2-} and NO3 -_{3}^{\ \,-} are carried out. The chemical relationships in Piper diagram identify Ca–HCO3–Cl and mixed Ca–Na–HCO3–Cl as most prevalent water types. Alkaline earth exceeds alkalis and weak acids exceed strong acids. Ionic ratios and Gibb’s
diagram suggest that silicate rock weathering and anthropogenic activities are the main processes that determine the ionic
composition in the study area. The nitrate appeared as a major problem of safe drinking water in this region. We recorded
highest nitrate concentration, i.e., 411 mg/l in one of the dug well. A comparison of groundwater quality in relation to drinking
water quality standards revealed that about half of the shallow aquifer samples are not suitable for drinking. 相似文献
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Zade CM Pete UD Patil SS Bhosale JD Hadole CD Kadam MS Bendre RS 《Journal of environmental science and health. Part. B》2012,47(2):136-143
Insect-growth regulators (IGRs) have been receiving foremost attention as potential means of selective insect control. Benzoyl phenyl urea (BPU) is a well-known IGR having chitin synthesis inhibitor activity. Mimics of BPU have been synthesized by suitable derivatization of a naturally occurring monoterpenoid, thymol (2-isopropyl-5-methyl phenol) to form a = series of substituted benzoyl thymyl thioureas (BTTUs) [IVa-f] and benzoyl thymyl ureas (BTUs) [Va-f]. The synthesized compounds have been characterized by (1)H and (13)C NMR, LC-MS and elemental analysis. These derivatives have been screened for their effect on total haemocyte count of Dysdercus koenigii. It has been observed that the introduction of substituted benzoyl thiourea and urea linkage into a thymol ring via an amino group results in higher activity than the parent compound thymol and a comparable pattern of results with the standard insect-growth regulators, Penfluron. Urea [Va-f] compounds exhibited greater effect on Total Haemocyte Count (THC) than thiourea [IVa-f]. Fluoro substitution enhanced the effect on THC more than chloro substituted compounds, while ortho-substitution resulted in a better effect than para-substitution. The results described in this paper are promising and provide new array of synthetic chemicals that may be utilized as insect growth regulators. 相似文献
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