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1.
Agarwal R Jayaraman G Anand S Marimuthu P 《Environmental monitoring and assessment》2006,114(1-3):489-504
The study focuses on assessing the status of respiratory morbidity in Delhi over a four years period from 2000–2003. An attempt was made to investigate the role of important pollutants (SO2, NO2, SPM and RSPM) and various meteorological factors (temperature minimum & maximum, relative humidity at 0830 and 1730 hrs. and wind speed) in being responsible for respiratory admissions on account of COPD, asthma and emphysema. The study showed that winter months had greater exposure risk as pollutants often get trapped in the lower layers of atmosphere resulting in high concentrations. Statistical analysis revealed that two pollutants have significant positive correlation with the number of COPD cases viz., SPM (r = 0.474; p < 0.01) and RSPM (r = 0.353; p < 0.05), while a meteorological factor temperature (minimum) has a significant negative correlation (r = −0.318; p < 0.05) with COPD. Stepwise multiple regression analysis was performed for COPD as dependent variable and R2 value of 0.33 was obtained indicating that SPM and RH(1730) were able to explain 33 percent variability in COPD. The partial correlation of SPM and RH(1730) on COPD was higher than any other combination and therefore they can be regarded as important contributing variables on COPD. 相似文献
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Jebakumar SR Kannan N Subramanian BR Jayaraman J 《Environmental pollution (Barking, Essex : 1987)》1989,61(3):227-234
Thirty-day-old seedlings of rice plants (IR-20 variety) from the nursery were transplanted into experimental plots and after 52 days were sprayed with phosphamidon (Dimecron 85% EC) at two dose-rates (0.38 kg a.i. ha(-1) and 0.76 kg a.i. ha(-1)). Residues of phosphamidon in the plant, soil and water were analysed by GLC, at various time intervals, and were found to decrease steadily up to 15 days. A second application of the pesticide was made on day 113 and grains harvested on day 138. The residue level in the plants was 0.12 microg g(-1) and in the grains 0.04 microg g(-1) with the high dose. This is slightly below the EPA prescribed tolerance level of 0.05 microg g(-1). The residues in both soil and water were very low, 24 h after spraying. 相似文献
4.
Govindasamy?BalaEmail author Ranjith?Gopalakrishnan Mathangi?Jayaraman Ramakrishna?Nemani N.?H.?Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):143-160
There is huge knowledge gap in our understanding of many terrestrial carbon cycle processes. In this paper, we investigate
the bounds on terrestrial carbon uptake over India that arises solely due to CO
2
-fertilization. For this purpose, we use a terrestrial carbon cycle model and consider two extreme scenarios: unlimited CO2-fertilization is allowed for the terrestrial vegetation with CO2 concentration level at 735 ppm in one case, and CO2-fertilization is capped at year 1975 levels for another simulation. Our simulations show that, under equilibrium conditions,
modeled carbon stocks in natural potential vegetation increase by 17 Gt-C with unlimited fertilization for CO2 levels and climate change corresponding to the end of 21st century but they decline by 5.5 Gt-C if fertilization is limited
at 1975 levels of CO2 concentration. The carbon stock changes are dominated by forests. The area covered by natural potential forests increases
by about 36% in the unlimited fertilization case but decreases by 15% in the fertilization-capped case. Thus, the assumption
regarding CO2-fertilization has the potential to alter the sign of terrestrial carbon uptake over India. Our model simulations also imply
that the maximum potential terrestrial sequestration over India, under equilibrium conditions and best case scenario of unlimited
CO2-fertilization, is only 18% of the 21st century SRES A2 scenarios emissions from India. The limited uptake potential of the
natural potential vegetation suggests that reduction of CO2 emissions and afforestation programs should be top priorities. 相似文献
5.
Mathivanan Krishnamurthy Chandirika Jayaraman Uthaya Vinothkanna Annadurai Govindarajan R. K. Meng Delong Yin Huaqun 《Journal of Polymers and the Environment》2021,29(6):1742-1751
Journal of Polymers and the Environment - In this study, the production and physicochemical characterization of exopolysaccharide (EPS) produced by Lysinibacillus fusiformis KMNTT-10 were... 相似文献
6.
Balasubramaniam B Sudalaiyadum Perumal A Jayaraman J Mani J Ramanujam P 《Waste management (New York, N.Y.)》2012,32(8):1539-1547
The petroleum fuel is nearing the line of extinction. Recent research and technology have provided promising outcomes to rely on biodiesel as the alternative and conventional source of fuel. The use of renewable source - vegetable oil constitutes the main stream of research. In this preliminary study, Waste Cooking Oil (WCO) was used as the substrate for biodiesel production. Lipase enzyme producing fungi Rhizopus oryzae 262 and commercially available pure lipase enzyme were used for comparative study in the production of Fatty Acid Alkyl Esters (FAAE). The whole cell (RO 262) and pure lipase enzyme (PE) were immobilized using calcium alginate beads. Calcium alginate was prepared by optimizing with different molar ratios of calcium chloride and different per cent sodium alginate. Entrapment immobilization was done for whole cell biocatalyst (WCB). PE was also immobilized by entrapment for the transesterification reaction. Seven different solvents - methanol, ethanol, n-propanol, n-butanol, iso-propanol, iso-butanol and iso-amyl alcohol were used as the acyl acceptors. The reaction parameters like temperature (30°C), molar ratio (1:3 - oil:solvent), reaction time (24 h), and amount of enzyme (10% mass ratio to oil) were also optimized for methanol alone. The same parameters were adopted for the other acyl acceptors too. Among the different acyl acceptors - methanol, whose reaction parameters were optimized showed maximum conversion of triglycerides to FAAE-94% with PE and 84% with WCB. On the whole, PE showed better catalytic converting ability with all the acyl acceptor compared to WCB. Gas chromatography analysis (GC) was done to determine the fatty acid composition of WCO (sunflower oil) and FAAE production with different acyl acceptors. 相似文献
7.
Rajiv K. Chaturvedi Ranjith Gopalakrishnan Mathangi Jayaraman Govindasamy Bala N. V. Joshi Raman Sukumar N. H. Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):119-142
We make an assessment of the impact of projected climate change on forest ecosystems in India. This assessment is based on
climate projections of the Regional Climate Model of the Hadley Centre (HadRM3) and the dynamic global vegetation model IBIS
for A2 and B2 scenarios. According to the model projections, 39% of forest grids are likely to undergo vegetation type change
under the A2 scenario and 34% under the B2 scenario by the end of this century. However, in many forest dominant states such
as Chattisgarh, Karnataka and Andhra Pradesh up to 73%, 67% and 62% of forested grids are projected to undergo change. Net
Primary Productivity (NPP) is projected to increase by 68.8% and 51.2% under the A2 and B2 scenarios, respectively, and soil
organic carbon (SOC) by 37.5% for A2 and 30.2% for B2 scenario. Based on the dynamic global vegetation modeling, we present
a forest vulnerability index for India which is based on the observed datasets of forest density, forest biodiversity as well
as model predicted vegetation type shift estimates for forested grids. The vulnerability index suggests that upper Himalayas,
northern and central parts of Western Ghats and parts of central India are most vulnerable to projected impacts of climate
change, while Northeastern forests are more resilient. Thus our study points to the need for developing and implementing adaptation
strategies to reduce vulnerability of forests to projected climate change. 相似文献
8.
Perumal Muthumari Karunakaran Nilavuckkarasi R. Balraj Ambedkar Jayaraman Dhanalakshmi Krishnan Jagannathan Prakash Aalan Britto John Arumugam Jeevakumar Muthukumar Venkadeshwara Prabhu 《Environmental science and pollution research international》2021,28(45):63532-63543
Environmental Science and Pollution Research - The anthropogenic carbon dioxide (CO2) denseness in the earth’s atmosphere is increasing day-to-day by combusting fossil fuels for power... 相似文献
9.
The packaging industry offers a wide range of pouching products to their clients in the food and beverage industries, healthcare industries and households as well. It is observed that pouching products are widely used and seemingly making them indispensable. Such practices are commonly found in Malaysia especially to parcel hot or cold food. The use of pouches raises two concerns namely solid waste disposal and food safety. The present study found more than 62% of the consumers purchase hot edible items in plastic bags daily or weekly because of its cost effectiveness and storage convenience. Consumers apparently are unperturbed by public campaigns against the use of plastic bags and neither do government regulations have any influence to reduce the use of plastic bags to parcel hot edible items. On the other hand, consumers are optimistic that the environmental and health hazards from the use of plastic bags to store hot edible items would only see a positive impact in the future. 相似文献
10.
Theerthagiri Jayaraman Karuppasamy K. Park Juhyeon Rahamathulla Nihila Kumari M. L. Aruna Souza Marciélli K. R. Cardoso Eduardo S. F. Murthy Arun Prasad Maia Gilberto Kim Hyun-Seok Choi Myong Yong 《Environmental Chemistry Letters》2023,21(3):1555-1583
Environmental Chemistry Letters - The decrease in fossil fuel usage and the projected 28% increase in the global energy demand by 2040 are calling for advanced methods to convert modern biomass... 相似文献