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971.
N. Mithil Kumar K. Varaprasad K. Madhusudana Rao A. Suresh Babu M. Srinivasulu S. Venkata Naidu 《Journal of Polymers and the Environment》2012,20(1):17-22
Poly (l-aspartic acid-citric acid) green copolymers were developed using thermal polymerization of aspartic acid (ASP) and citric
acid (CA) followed by direct bulk melt condensation technique. Antibacterial properties of copolymer of aspartic acid based
were investigated as a function of citric acid content. This study is focused on the microorganism inhibition performance
of aspartic acid based copolymers. Results showed that inhibition properties increase with increasing citric acid content.
Characterization of obtained copolymers was carried out with the help of infrared absorption spectra (FTIR), x-ray diffraction
(XRD), differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA). The antibacterial activity of copolymers
against bacteria like E-coli, Bacillus and pseudomonas was investigated. The copolymers showed excellent antimicrobial activities
against three types of microorganisms. Overall studies indicated that the above copolymers possess a broad wound dressing
activity against above three types of bacteria and may be useful as antibacterial agents. 相似文献
972.
Bioavailability and risk assessment of trace metals in sediments of a high-altitude eutrophic lake,Ooty, Tamil Nadu,India 总被引:1,自引:0,他引:1
Parthasarathy Purushothaman Asok Manju Ranjan Rajesh Kumar Swain Sujit Kumar 《Environmental science and pollution research international》2021,28(15):18616-18631
Environmental Science and Pollution Research - Ooty lake, in the southern part of India, has raised huge concern about the role of metals in a lake due to increasing anthropogenic activities.... 相似文献
973.
It is widely acknowledged that Small Island Developing States (SIDS) are particularly vulnerable to climate change and will continue to require external support to adapt to current and future impacts. The international development community plays an important role in supporting SIDS adapt to climatic changes, and calls for increased international commitment have been made. However, how the vulnerability of SIDS to climate change is being conceptualised and, subsequently, how adaptation programmes are conceived and designed by the international development community are yet to be critically explored. Using Timor-Leste as a case study, this study examines the conceptual trends underpinning 32 donor-led adaptation programmes implemented from 2010 to the present date. Results show that donor-led adaptation programmes continue to conceptualise climate change vulnerability as a biophysical issue rather than a consequence of the dynamic interactions between political, institutional, economic and social structures. Adaptation policy responses therefore have limited ability to target more nuanced and broader-scale structures affecting SIDS and may be falling short in their efforts to reduce the vulnerability of SIDS. We argue that it is critical that the international development community re-conceptualise its approach to vulnerability reduction in SIDS. We conclude by highlighting how the Paris Agreement, with its expanding understanding of vulnerability, can act as a useful instrument to promote such changes. 相似文献
974.
Yadav Deepak Kumar Chawla Kanhaiya Jain I. P. Lal Chhagan 《Environmental science and pollution research international》2021,28(4):3866-3871
Environmental Science and Pollution Research - Reversible hydrogen storage in MgH2 under specified conditions is a possible way for the positive reception of hydrogen economy, in which the... 相似文献
975.
Das Vikas Kumar Hansda Sunil Debnath Koustuv Chaudhuri Susanta 《Environment, Development and Sustainability》2021,23(10):15290-15313
Environment, Development and Sustainability - Sundarban area of the lower Gangetic plain experiences embankment failure almost every year due to the formation of toe undercuts. Waves generated due... 相似文献
976.
P. R. Thawale S. Satheesh Babu R. R. Wakode Sanjeev Kumar Singh Sunil Kumar A. A. Juwarkar 《Environmental monitoring and assessment》2011,177(1-4):527-535
The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution. 相似文献
977.
Sekaran G Ramani K Ganesh Kumar A Ravindran B John Kennedy L Gnanamani A 《Journal of environmental management》2007,84(2):123-133
Domestic wastewater contains a considerable amount of pathogenic organisms besides non-biodegradable organics. The conventional technologies followed for the treatment of domestic wastewater are less efficient in removing pathogenic organisms despite substantial removal of dissolved organics. The focal theme of the present investigation was to use a chemo-autotrophic activated carbon oxidation (CAACO) system, an immobilized cell reactor using chemoautotrophs (Bacillus sp.) for the treatment of domestic wastewater. The oxidation of organics and Escherichia coli in wastewater is controlled by the parameters space time, O(2)/COD, bed height and cod loading. The scheme comprised of anaerobic treatment, sand filtration and CAACO treatment removed BOD. COD, Total organic carbon (TOC), dissolved protein, total Kjeldhal nitrogen (TKN) and bacterial count (most probable number (MPN)) by 81%, 92%, 84%, 94%, 93% and 99.9997%, respectively. The low concentration of E. coli in the CAACO-treated wastewater was completely eliminated through UV irradiation in 3 min at 254 nm. 相似文献
978.
Water quality and phytoplankton characteristics in the Palk Bay, southeast coast of India 总被引:1,自引:0,他引:1
Sridhar R Thangaradjou T Kumar SS Kannan L 《Journal of environmental biology / Academy of Environmental Biology, India》2006,27(3):561-566
The present study was carried out to determine the water quality in terms of physicochemical characteristics and plankton distribution in the coastal waters of Kattumavadi, Palk Bay for a period of one year from April 2002 to March 2003. Air and surface water temperatures varied from 28 degrees C to 32.50 degrees C and from 27.5 to 32.0 degrees C while light extinction coefficient (LEC) varied between 0.95 and 1.85. Salinity ranged from 26.0 to 34.5 per thousand and the pH ranged between 7.95 and 8.35. Variation in dissolved oxygen content was from 4.15 to 7.18 ml(-1), and the particulate organic carbon (POC) content varied between 0.49 and 2.28 mgCl(-1). Concentrations of nutrients viz. nitrate (2.15 to 8.28 microM), nitrite (0.12 to 0.62 microM), inorganic phosphate (1.28 to 2.15 microM) and reactive silicate (5.15 to 12.52 microM) also varied independently. Chlorophyll a content ranged from 0.28 to 1.48 mg m(-3) and the primary productivity, from 4.19 to 16.08 mgCm(-3) hr(-1). The present study recorded a total of 43 species of planktonic diatoms and two species of blue-green algae. Population density of phytoplankton varied from 18,000 to 34,000 cells l(-1). Percentage composition, of the diatoms showed minimum values during the monsoon season and the maximum values during the premonsoon season. 相似文献
979.
Breast milk is the natural and optimal food for the infants. In addition to meeting the nutritional needs, breast milk provides numerous immunological, developmental, psychological, ecological and practical advantages. The levels of the DDT and HCH residues in human milk collected from remote rural part of Agra were analysed. Beta and gamma isomers of HCH accounts for the major residue of total HCH excreted in breast milk. Delta-HCH was not detected in the samples. 95% of the samples were found to be contaminated with DDT and its metabolites. DDD was found in 88% of the samples analyzed. The total concentration of DDT and HCH were found lower than the previous studies carried out in India. The study shows the decreasing levels of these organochlorine pesticides from the environment. Total concentration of total DDT is higher than total HCH. 相似文献
980.
Silt composed predominately of quartz occurs abundantly in the sedimentary material found in deposits worldwide. Its origin is still the subject of many debates, but one acknowledged source is due to glacial grinding. To examine this problem and test the apparent contradictory evidence in the literature, a series of experiments were performed. In these experiments, the Bromhead ring shear apparatus was used as it can simulate glacial grinding due to its uninterrupted shearing action; hence, it provides an effective reproduction of glacial grinding. Experiments conducted on unweathered sand-sized vein quartz produced little silt, while use of sand from a sedimentary deposit, Leighton Buzzard sand, produced plentiful silt. Experimental results suggest that there is an internal mineralogical control on the formation of quartz silt particles. It is argued that the processes involved in the formation of quartz introduce defects (Moss defects) into the low-quartz crystal structure, demonstrated by the presence of peaks in the particle size curve around 20 μm. This indicates that there is a lithological control for the silt yielded under weathering, and this could explain why a pronounced mode at around 20–60 μm is commonly observed in silts, such as loess. 相似文献