排序方式: 共有24条查询结果,搜索用时 15 毫秒
1.
Harish Venkatakrishnan Youming Tan Maszenan bin Abdul Maji Santosh Pathak Antonius Yudi Sendjaj Dongzhe Li Jerry Jian Lin Liu Yan Zhou Wun Jern Ng 《环境科学学报(英文版)》2014,26(4):875-884
A high strength chemical industry wastewater was assessed for its impact on anaerobic microbial com- munity dynamics and consequently mesophilic methane generation. Cumulative methane production was 251 mL/g total chemical oxygen demand removed at standard temperature and pressure at the end of 30 days experimental period with a highest recorded methane percentage of 80.6% of total biogas volume. Volatile fatty acids (VFAs) analysis revealed that acetic acid was the major intermediate VFAs produced with propionic acid accumulating over the experimental period. Quantitative analysis of microbial communities in the test and control groups with quantitative real time polymerase chain reaction highlighted that in the test group, Eubacteria (96.3%) was dominant in comparison with methanogens (3.7%). The latter were dominated by Methanomicrobiales and Methanobacteriales while in test groups increased over the experimental period, reaching a maximum on day 30. Denaturing gradient gel electrophoresis profile was performed, targeting the 16S rRNA gene of Eubacteria and Archaea, with the DNA samples extracted at 3 different time points from the test groups. A phylogenetic tree was constructed for the sequences using the neighborhood joining method. The analysis revealed that the presence of organisms resembling Syntrophomonadaceae could have contributed to increased production of acetic and propionic acid intermediates while decrease of organisms resembling Pelotomaculum sp. could have most likely contributed to accumulation of propionic acid. This study suggested that the degradation of organic components within the high strength industrial wastewater is closely linked with the activity of certain niche microbial communities within eubacteria and methanogens. 相似文献
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The kinetics of oxidation of methylhydrazine () and 1,1-dimethylhydrazine () by dissolved oxygen in water has been measured at various acidities as a function of catalyst (cupric ion) concentration. In dilute solutions the oxidation occurs through a cupric ion catalyzed process as well as by an uncatalyzed step. The extent of formation of nitrosodimethylamine () depends upon the initial concentration. In dilute solutions is not formed, but in more concentrated solutions, formation increases with increasing content, reaches a maximum at 60–80% (by volume) and then decreases. The yield appears to approximately parallel the viscosity of the medium, and it is speculated that the factors which control viscosity may also be responsible for governing formation. 相似文献
3.
Harish Kumar Jeswani Adisa Azapagic Philipp Schepelmann Michael Ritthoff 《Journal of Cleaner Production》2010,18(2):120-127
Life Cycle Assessment (LCA) has matured over the past decades and become part of the broader field of sustainability assessment. To strengthen LCA as a tool and eventually increase its usefulness for sustainability decision-making, it is argued that there is a need to expand the ISO LCA framework by integration and connection with other concepts and methods. This paper explores the potential options for deepening and broadening the LCA methodologies beyond the current ISO framework for improved sustainability analysis. By investigating several environmental, economic and social assessment methods, the paper suggests some options for incorporating (parts of) other methods or combining with other methods for broadening and deepening the LCA. 相似文献
4.
Shyam Lal Sethuraman Venkataramani Manish Naja Jagdish Chandra Kuniyal Tuhin Kumar Mandal Pradip Kumar Bhuyan Kandikonda Maharaj Kumari Sachchida Nand Tripathi Ujjaini Sarkar Trupti Das Yerramsetti Venkata Swamy Kotalo Rama Gopal Harish Gadhavi Modathi Kottungal Satheesh Kumar 《Environmental science and pollution research international》2017,24(26):20972-20981
Surface ozone is mainly produced by photochemical reactions involving various anthropogenic pollutants, whose emissions are increasing rapidly in India due to fast-growing anthropogenic activities. This study estimates the losses of wheat and rice crop yields using surface ozone observations from a group of 17 sites, for the first time, covering different parts of India. We used the mean ozone for 7 h during the day (M7) and accumulated ozone over a threshold of 40 ppbv (AOT40) metrics for the calculation of crop losses for the northern, eastern, western and southern regions of India. Our estimates show the highest annual loss of wheat (about 9 million ton) in the northern India, one of the most polluted regions in India, and that of rice (about 2.6 million ton) in the eastern region. The total all India annual loss of 4.0–14.2 million ton (4.2–15.0%) for wheat and 0.3–6.7 million ton (0.3–6.3%) for rice are estimated. The results show lower crop loss for rice than that of wheat mainly due to lower surface ozone levels during the cropping season after the Indian summer monsoon. These estimates based on a network of observation sites show lower losses than earlier estimates based on limited observations and much lower losses compared to global model estimates. However, these losses are slightly higher compared to a regional model estimate. Further, the results show large differences in the loss rates of both the two crops using the M7 and AOT40 metrics. This study also confirms that AOT40 cannot be fit with a linear relation over the Indian region and suggests for the need of new metrics that are based on factors suitable for this region. 相似文献
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The biological removal of phosphates was carried as a part of treatment strategy. Vetiveria zizanioides (L.) Nash belonging to the family Poaceae was used for biological removal of biostimulants. Vetiver reportedly has mycorrhizal
association; besides having potential for removal of PO4
−3 also showed allelopathic affect on the microorganisms present in the water. In fact after a period of 96 h old roots of this
plant have been found to have killing effects on the E. coli, Enterobacter spp. Pseudomonas spp. belonging to the family Enterobacteriaceae. The paper is opening a new face of study. 相似文献
6.
Santhanakrishnan Harish Mani Navaneethan Jayaram Archana Suruttaiyaudiyar Ponnusamy Chellamuthu Muthamizhchelvan Shimomura Masaru 《Environmental science and pollution research international》2021,28(15):18768-18777
Environmental Science and Pollution Research - Herein we synthesized a novel structure of mesoporous TiO2 decorated on 1D ZnO nanorods for environmental remediation. The effect of mesoporous TiO2... 相似文献
7.
Enrichment and fractionation of heavy metals in bed sediments of River Narmada, India 总被引:2,自引:0,他引:2
A metal fractionation study on bed sediments of River Narmada in Central India has been carried out to examine the enrichment
and partitioning of different metal species between five geochemical phases (exchangeable fraction, carbonate fraction, Fe/Mn
oxide fraction, organic fraction and residual fraction). The river receives toxic substances through a large number of tributaries
and drains flowing in the catchment of the river. The toxic substances of particular interest are heavy metals derived from
urban runoff as well as municipal sewage and industrial effluents. Heavy metals entering the river get adsorbed onto the suspended
sediments, which in due course of time settle down in the bottom of the river. In this study fractionation of metal ions has
been carried out with the objective to determine the eco-toxic potential of metal ions. Although, in most cases (except iron)
the average trace/heavy metal concentrations in sediments were higher than the standard shale values, the risk assessment
code as applied to the present study reveals that only about 1–3% of manganese, <1% of copper, 16–19% of nickel, 4–20% of
chromium, 1–4% of lead, 8–13% of cadmium and 1–3% of zinc exist in exchangeable fraction and therefore falls under low to
medium risk category. According to the Geo-accumulation Index (GAI), cadmium shows high accumulation in the river sediments,
rest of other metals are under unpolluted to moderately polluted class. 相似文献
8.
Regina E. Ducret-Stich Ming-Yi Tsai Devraj Thimmaiah Nino Künzli Philip K. Hopke Harish C. Phuleria 《Environmental science and pollution research international》2013,20(9):6496-6508
Although trans-Alpine highway traffic exhaust is one of the major sources of air pollution along the highway valleys of the Alpine regions, little is known about its contribution to residential exposure and impact on respiratory health. In this paper, source-specific contributions to particulate matter with an aerodynamic diameter?<?10 μm (PM10) and their spatio-temporal distribution were determined for later use in a pediatric asthma panel study in an Alpine village. PM10 sources were identified by positive matrix factorization using chemical trace elements, elemental, and organic carbon from daily PM10 filters collected between November 2007 and June 2009 at seven locations within the village. Of the nine sources identified, four were directly road traffic-related: traffic exhaust, road dust, tire and brake wear, and road salt contributing 16 %, 8 %, 1 %, and 2 % to annual PM10 concentrations, respectively. They showed a clear dependence with distance to highway. Additional contributions were identified from secondary particles (27 %), biomass burning (18 %), railway (11 %), and mineral dust including a local construction site (13 %). Comparing these source contributions with known source-specific biomarkers (e.g., levoglucosan, nitro-polycyclic aromatic hydrocarbons) showed high agreement with biomass burning, moderate with secondary particles (in winter), and lowest agreement with traffic exhaust. 相似文献
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