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81.
Dutta P Prakash A Bhattacharyya DR Khan SA Gogoi PR Sharma CK Mahanta J 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(5):695-699
Entomological surveys were conducted for three consecutive years in core and buffer zone of the Dibru-Saikhowa biosphere reserve in pre monsoon, monsoon and post-monsoon seasons. A total of 52 species of mosquitoes under eleven genera have been detected. The genus Anopheles (18 species) was the predominant followed by Culex, Aedes, Mansonia, Armigeres, Mimomyia, Ochlerostatus, Malaya, Toxorhynchites, Ficalbia and Aedeomyia. The buffer zone of the forest reserve where human habitations are there exhibited the presence of maximum number of species (49 species under 10 genera) in comparison to core zone (42 species under 10 genera). In buffer zone, maximum numbers of species (38) were recorded in monsoon season followed by post- monsoon (35 species) and Pre-monsoon season (34 species). Whereas in core zone, maximum number of species were collected in post monsoon season followed by pre monsoon season and monsoon season. In Core and buffer zone, the maximum species were recorded from the ground pool habitat and slow flowing stream respectively. Among the disease vectors, the potential Japanese encephalitis vectors incriminated in India were very much prevalent. This study provides the list of available mosquito species recorded for the first time in the Dibru-Saikhowa biosphere reserve. 相似文献
82.
Ahmad Tasneem Nazar Sonaina Ahmad Kafeel Khan Zafar Iqbal Bashir Humayun Ashfaq Asma Munir Mudasra Munir Zunaira Hussain Khadim Alkahtani Jawaher Elshikh Mohamed Soliman Nadeem Muhammad Malik Ifra Saleem 《Environmental science and pollution research international》2021,28(23):29110-29116
Environmental Science and Pollution Research - The instant endeavor was undertaken to monitor copper (Cu) contents in water, soil, forage, and cow’s blood impacted by heavy automobiles in... 相似文献
83.
84.
Mimi H. Hassim Markku Hurme Paul R. Amyotte Faisal I. Khan 《Journal of Loss Prevention in the Process Industries》2012,25(5):820-829
Fugitive emissions are among the major concerns of industrial process releases. The emissions cause problem to various aspects including the environment, health, and economic. Early evaluation of process hazards is beneficial because process can be made inherently benign at lower cost. This paper discusses two important aspects of fugitive emissions assessment during process design – the quantification and the prevention strategies.For the quantification part, three methods are presented for fugitive emissions estimation during the process design. They are tailored to data available in simple process flow diagram (PFD), detailed PFD, and piping & instrumentation diagram (PID). Such methods are needed as early emissions estimation allows production routes and process designs with lower emissions to be selected. The fugitive emissions estimation and methods to abatement are demonstrated on a benzene process case study. Valves are found to be the major emission source with 50% of fugitive emissions of process area in a base case of petrochemical process, in which no fugitive emission reductions are yet made. Pumps without mechanical seals come second with 30% and flanges with 8% of emissions. Inherently safer design keywords can be applied to prevent fugitive emissions in the process plants. Substitution is the most applicable keyword in fugitive emission reduction of existing plants.The emission rate calculations together with estimation of health risk give a sound background for the decision making on elimination of emissions at source through equipment and piping changes. The case study presented reveals that by substituting emission prone components by inherently low-leaking ones, the plant emissions can be reduced over 90% in practice. This is created mainly by replacing rising stem valves with ball valves, installing double mechanical pump seals or hermetic pumps and making changes in sampling and relief systems. Ideally by also changing flanges to welded connections, which is not viable for various reasons, the emissions could be reduced nearly to zero. 相似文献
85.
86.
A. A. Khan 《Journal of Loss Prevention in the Process Industries》1990,3(4):406-408
An assignment to carry out a hazard study and risk analysis of a gas processing complex has been described briefly, wherein well known procedures have been used to identify and investigate potential hazards. A method of avoiding unintentional overfilling of LPG storage tanks has been recommended, which utilizes the existing level control instruments. 相似文献
87.
88.
Laboratory studies were conducted to determine the adsorption/desorption equilibrium of carbofuran between four divergently textured soils and distilled water and an aqueous solution of 0.01?mol?L?1 β-cyclodextrin using a batch equilibrium technique. The determined adsorption isotherms for silt loam soils were of L-shaped, for sandy loam soil S-shaped, in agreement with a Freundlich isotherm. In the presence of β-cyclodextrin, the adsorption of carbofuran to the four soils was lower than with distilled water. Positive hysteresis was observed in all soils with distilled water, negative hysteresis when using a solution of β-cyclodextrin as desorbent. The results indicate the potential use of β-cyclodextrin for remediation of pesticide-contaminated soils. 相似文献
89.
Nutrient-impregnated charcoal: an environmentally friendly
slow-release fertilizer 总被引:20,自引:0,他引:20
Modabber Ahmed Khan Ki-Wook Kim Wang Mingzhi Bu-Kug Lim Weon-Hee Lee Jong-Yoon Lee 《The Environmentalist》2008,28(3):231-235
The widespread contamination of surface and ground water quality from the heavy use of fertilizer in modern agriculture is
the current concern. Therefore, this study was carried out to develop a slow-release fertilizer using charcoal. The morphology
of the charcoal impregnated fertilizer was investigated by scanning electron microscopy (SEM). This study also evaluated the
release patterns of N, P, and K from impregnated charcoal using a simulated soil solution and distilled water as leaching
solutions. The patterns of N, P, and K releases were examined in both static and continuous-flow conditions for 360 h. Releases
of N, P, and K from impregnated charcoal were found to be slow and steady. However, the release trends of N, P, and K were
higher in soil solution than distilled water under both the above conditions. Dissolution occurred when N, P, and K were released
in the above leached solutions. As a result, the fertilizer impregnated charcoal could be developed as slow-release type fertilizer
to minimize the contamination. 相似文献
90.
This research article demonstrates biodiesel synthesis through the methanolysis of the oily contents (4.02 ± 0.27% w/w on dried basis) of Dictyota dichotoma collected from the coast of Hawksbay, Pakistan. The metal oxides (CaO, MgO, ZnO, and TiO2) used as nanocatalysts were refluxed (5% K2SO4), calcinated (850 °C) and characterized by Atomic Force Microscopy (AFM) which produced 93.2% w/w FAME (biodiesel) at relatively mild condition (5% catalyst, 65 °C, 3 h, 18:1 molar ratio) using CaO. Whereas, MgO, ZnO, and TiO2 produced 92.4%, 72.5%, and 31.8% w/w FAME, respectively at elevated condition (225 °C). Thus, CaO was considered to be the best catalyst among the others. This tri-phase reaction require continuous fast mixing and the yield depends on the reaction parameters like catalyst amount, temperature, reaction time and molar ratio (methanol: oil). The reusability of these heterogeneous catalysts simplified the purification step, reduced the waste generation and make the final product technically and economically viable. 相似文献