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Assessment of Annual Effective Dose from the Indoor Radon in Bathinda District of Punjab in India Full text
2019
Amit Arora, Rohit Mehra, Rajeev Kumar Garg and Anand K. Tyagi
Carrying out of indoor radon studies have been done in the 50 dwellings of Bathinda district (Punjab), India using LR-115 type II cellulose nitrate films in the bare mode. The films were exposed into four consecutive trimesters, i.e. from March 2010 to February 2011. The work has been undertaken for health risk assessment. The calibration constant of 1 track cm-2day-1 equal to 50 Bqm-3 (Becquerel/m3) was used. In the present study average radon values vary from 83.15 (BTD-7) to 124.35 (BTD-8) Bqm-3 in different villages, which are higher than the word average value of 40 Bqm-3. The inhabitants of the area of study receive average annual radiation dose varying from 1.41 (BTD-7) - 2.12 (BTD-8) mSv (millisievert). The effective dose is found to be less than lower limit of the recommended action level (3-10 mSv). The value of radon for the first floor portion of the same dwelling is lower in comparison to the ground floor. The values in the cemented floors are lower than in the dwellings with the un-cemented floors. The indoor radon values are more in very poorly ventilated dwellings in comparison to the very well-ventilated dwellings.
Show more [+] Less [-]Review of the Sedimentological and Geochemical Approaches for Environmental Assessment of River Sadong, Samarahan-Asajaya District Sarawak, Malaysia Full text
2019
Omolayo Ajoke Omorinoye, Zaini Bin Assim, Ismail Bin Jusoh, Naseer Inuwa Durumin Iya and Isaac John Umaru
This paper presents an overview of the implication of geomorphology and sedimentology on the chemical characteristics of sediments of River Sadong, Malaysia. There is limited published work on the effect of topography, climate, soil and geology on the sediments lying in the River Sadong. Studies have been undertaken around Kota Samarahan and Asajaya areas whereby some heavy metal constituents and their environmental effects were determined. The study entails the description of the depositional processes alongside with physical and geochemical changes, without neglecting natural and anthropogenic effects.
Show more [+] Less [-]Study on the Influence of Land Use Patterns on the Comprehensive Harnessing Effects of Soil and Water Erosion Full text
2019
Zhaoya Chen, Lijun Ma, Fengyu Guo, Xiangling Ma and Yu Chu
Comprehensive harnessing of soil and water erosion can change the regional surface environment, improve ecological conditions, and promote regional social and economic development, which can also achieve good ecological, social, and economic benefits for the purpose of preventing and controlling soil erosion. Scientific evaluation of soil erosion comprehensive harnessing benefits is presented, and analysis of influencing factors is adopted, which is an important basis for further understanding of work effectiveness and optimization of governance measures. The research selects Taihang Mountain Area of Hebei Province as the research area. This paper evaluates the comprehensive treatment benefits of 16 typical small watersheds by multi-level fuzzy evaluation method, and uses the exponential, linear, logarithmic, power function and polynomial as the model. The correlation between land use type area and comprehensive treatment benefit was studied, and the corresponding improvement of management efficiency has been proposed in order to provide a reference for optimizing the comprehensive management mode of small watersheds in Taihang Mountain area and improving the efficiency of comprehensive management.
Show more [+] Less [-]Impact of Land Use Change on Hydrological Response of Krueng Aceh Watershed in Aceh Province, Indonesia Full text
2019
Bos Ariadi Muis
Population growth and improvement in the people’s economy have caused the need for space to grow and have changed land use in the Krueng Aceh watershed. This study on the effect of changes in land use on the Krueng Aceh watershed hydrological response as a step to anticipate water shortage in the future using the geographical information analysis and the river regime coefficient (RRC) method approach. The results of this study revealed that the functional shifts from primary forests to production forests and from brushland to ricefield and settlements increased the RRC value from 14.59 to 56.74 in the last 20 years. The hydrological response showed that 18% of the water had the potential to not infiltrate and become runoff. The effect is a reduction in groundwater supply, flooding in the rainy season, drought in the dry season, and clean water scarcity in the future. The management of the future must be based on one river, one planning, and one management system principle.
Show more [+] Less [-]A Feasible and Green Approach for Developing Hydro gen Energy Full text
2019
Wenting Zhang, Yifeng Liu and Yingmei Xu
Hydrogen is recognized as the green energy with the greatest potential for future development, but currently, China’s hydrogen production is highly dependent on raw fossil materials, which conflicts with the original intention of developing hydrogen energy. As the abandoned hydropower problem in Southwestern China is serious. The current strategy can be focused using surplus hydropower to produce hydrogen in a green way. In this study, the technical cost and advantage of hydrogen produced using surplus hydropower using the levelized cost of energy model was analyzed. The results show that cheap surplus hydropower will considerably reduce the cost of hydrogen produced using electrolyzing water, and the cost is comparable to that of coal gasification hydrogen production. The hydropower to be abandoned by Southwestern China annually can drive the hydrogen production with 1.2 million tons per year, providing a technically and economically feasible approach to developing hydrogen energy.
Show more [+] Less [-]Evaluation of Organophosphorus Pesticide Residue in Cotton of Tijara Tehsil, Alwar, Rajasthan Full text
2019
Sucheta Yadav and Subroto Dutta
Cotton is one of the most important fibres and cash crop of India, which plays a dominant role in the country’s industrial and agricultural economy. About 60% of all commercialized agrochemicals, are insanely applied on cotton fields so that cotton has become one of the most polluted and chemical-intensive agricultural crops in the world. The present study was undertaken to determine the concentration of different organophosphorus pesticides residue in cotton samples collected from agriculture fields of Tijara tehsil, Alwar. A total of 150 samples were randomly collected from the cotton farm. Concentrations of all pesticides in the cotton samples were determined by GC/MS and LC-MS. About 38% of the total analysed samples were contaminated with different residues, among which 10.66% were having the concentration of pesticide residue above the MRL. The study revealed that cotton is highly contaminated with Monocrotophos (22%) followed by Acephate (10%), Chlorpyrifos (7.33%) and Profenofos (5.33%). The possible reasons for high levels of pesticides in cotton are the massive use of pesticides and farmers were not having sufficient scientific knowledge about the chemical nature of pesticides that have been used or the effects of pesticides on the environment and the effects of pesticides exposure on public health, when using them indiscriminately. The presence of pesticides in cotton samples is a serious threat to humans because they further show pesticide residues in cotton products. Therefore, it is recommended to continuously monitor the use of this pesticide in the study areas.
Show more [+] Less [-]Calculation of Water Volume for Sediment Transport in the Sediment-laden River of the Main Stream of Liaohe River, Northern China Full text
2019
Xin Yu, Haoming Fan, Liquan Liu and Jing Chen
The water volume for sediment transport affects the distribution of sediments in rivers and offers important guidance for river dredging, management and remediation. In this paper, with daily water and sediment data of major hydrological stations of main stream of Liaohe River from 1988 to 2010, we calculated the average water volume and unit water volume for sediment transport of the year with the methods of sediment discharge, sediment concentration and erosion and silting ratio correction that are based on net water volume method. We analyzed the relations between change process of water volume for sediment transport and its impact factors to identify the critical water volume for sediment transport for non-scouring and non-silting situation. The results showed that (1) according to the calculation with the hydrological data from the major hydrological stations in Tongjiangkou, Tieling, Mahushan, Ping’anpu and Liujianfang, the average water volume and the unit water volume for sediment transport during the flood season of the year were 13.88×108m3 and 1136.62m3/t respectively; (2) According to the theoretical calculation, the water demand model for hydraulic sediment dredging in the major reaches of the main stream of Liaohe River was determined and there was linear function relationship between the sediment discharge and the water demand. When the channel kept the sediment from silting, the water demand at Tieling was ≥18.73×108m3, ≥5.49×108m3 at Mahushan, ≥2.90×108m3 at Ping’anpu and ≥10.97×108m3 at Liaozhong. In a word, net water volume method can accurately calculate the amount of sediment transport in sediment-laden rivers with a prospect of broad application.
Show more [+] Less [-]Metal Concentration of Water of Amaravathi and Thirumoorthy Reservoirs in Tamil Nadu, India Full text
2019
N. Natarajan, V. Vivekk Velusamy, S. Nishar Ahamed, M. Imayaprakash and S. Dineshkumar
Reservoirs are the major source of water supply in many localities for meeting the water demand of the people, and hence it is important to monitor the metal concentration of the water stored in such reservoirs for the benefit of the people in terms of drinking water and irrigation. The main objective of this study is to monitor the metal concentrations of Arsenic (As), Boron (B), Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Nickel (Ni), Lead (Pb), Selenium (Se), and Zinc (Zn) in the water of the Amaravathi and Thirumoorthy reservoirs located in the Tiruppur district of the state of Tamil Nadu, India. Results indicate that the water collected from the Thirumoorthy reservoir is free from metal contamination while that from the Amaravathi reservoir has a marginal contamination of Fe concentration. Thus, the water stored in these reservoirs is suitable for drinking and irrigation purpose.
Show more [+] Less [-]Purification, Molecular Cloning and Expression of Three Key Saponin Hydrolases from Trichoderma reesei, Trichoderma viride and Aspergillus fumigatus Full text
2019
Jiamin Huang, Yangyang Wang, Linshan Fang, JiaojunJin, Suhui Ye, Wenjing Dun and Yuling Zhu
Microbial transformation is an environment-friendly approach to produce diosgenin from natural plant tubers. However, improving the bioconversion efficiency of this process remains a challenge. Saponin hydrolase plays a major role during the transformation. a-rhamnase, b-glycosidase and C3 b-glycosidase have been identified as three key enzymes in the stepwise conversion of saponins to diosgenin. The three enzymes have not been molecularly characterized. Here, a-rhamnase, b-glycosidase and C3 b-glycosidase were purified from Trichoderma reesei, Trichoderma viride and Aspergillus fumigatus, respectively. SDS-polyacrylamide gel electrophoresis showed that the molecular masses of the three enzymes were approximately 60, 36 and 56 kDa, respectively. a-rhamnase could efficiently hydrolyse the terminal rhamnoside on the C3 site in saponins. b-glycosidase could cleave the terminal b-glycoside at the C3 position, while C3 b-glycosidase demonstrated significant affinity to the b-glycoside at the C3 position. The amino acid sequences of the three saponin hydrolases were determined. Reverse transcription-PCR was used to clone the three plasmids with lengths of approximately 1035, 1416 and 1752 bp from the strains and expressed in Escherichia coli. The recombinant saponin hydrolases from the recombinant strains also demonstrated the hydrolysing of rhamnoside and glycosides of saponins similar to those of the wild-type hydrolases from T. reesei, T. viride, and A. fumigatus. The findings could facilitate the construction of recombinant cells by gene fusion to produce diosgenin from plant tubers.
Show more [+] Less [-]Biofuel from Bryophyta as an Alternative Fuel for Future Full text
2019
Sandeep Sirohi, Chitra Yadav and Debjyoti Banerjee
Today’s growing demand for energy has emphasized the need for the search for renewable resources. This demand can be met with by using alternative resources such as biofuel, rather than just depending on non-renewable resources. Therefore, the present study has been undertaken to extract lipid from a species of Bryophyta, i.e. Marchantia polymorpha. 0.044 g of lipid was extracted from 8 g of the bryophyte. Bligh and Dyer method was used for the extraction of lipid. It is a multi-step process in which methanol, chloroform, and NaCl play an important role in the extraction of bioproduct in the form of oily bodies. This small step taken towards energy utilization and conservation will open the new vista to mitigate the problem of energy crisis.
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