排序方式: 共有13条查询结果,搜索用时 359 毫秒
1.
Kevin A. Morin John A. Cherry Nand K. Dav Tjoe P. Lim Al J. Vivyurka 《Journal of contaminant hydrology》1988,2(4)
In this second paper of a series on groundwater seepage from uranium tailings, the general geochemical behavior of radionuclides is described and then applied to data from the field site, Seepage Area A of the Nordic Main impoundment near Elliot Lake, Ontario. The delineation of radionuclide behavior requires (1) the calculation of total element concentration by the summation of concentrations of each element's isotopes (the isotopic concentrations are calculated from the isotopes' radioactivities), (2) the evaluation of solid-liquid interactions using total element concentrations, and (3), for particular isotopes, the evaluation of the extent to which parental geochemical behavior causes a deviation in the isotope's behavior from that of its total element. A computerized speciation program, WATRAD, is used to evaluate aqueous complexation and mineral saturation indices of radium, actinium, thorium, and uranium. Data from Seepage Area A on isotopes of these four elements plus 210Pb show that the geochemical behavior of radionuclides can be best defined on an individual isotopic basis rather than on an elemental basis. 相似文献
2.
Thuan Van Tran Duyen Thi Cam Nguyen Hanh T.N. Le Dai-Viet N. Vo Sonil Nand Trinh Duy Nguyen 《环境科学学报(英文版)》2020,32(7):137-150
Aquatic contamination of diclofenac (DCF), an emergent non-steroidal anti-inflammatory drug (NSAIDs), can result in adverse effects to many ecosystems through biomagnification. Hence, introducing effective remediation techniques to sequester the pharmaceutical wastes is highly fundamental to prevent their accumulation in the environment. Generally, adsorption has been presented as a green and efficient approach. Herein, we report the characterization and application of the novel magnetic nanocomposite ([email protected]2O4) derived from cobalt-based ferrite (CoFe2O4) and graphene oxide (GO) for DCF adsorption. For the optimization procedure, the response surface methodology (RSM) was adopted to investigate the impacts of DCF concentration (1.6–18.4 mg/L), DCF dosage (0.08–0.92 g/L), and solution pH (2.6–9.4) to find the optimum conditions for DCF removal, at 10.5 mg/L, 0.74 g/L, and pH 4, respectively. For the adsorption experiments, the kinetic, isotherm, thermodynamic, and intraparticle diffusion models were systematically studied. Moreover, we have elucidated the role of functional groups on the surface of [email protected]2O4 in enhancing the adsorption of DCF drug. With good removal efficiency (up to 86.1%), high maximum adsorption capacity (32.4 mg/g), [email protected]2O4 can be a potential candidate to eliminate DCF drug from water. 相似文献
3.
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
5.
Afzal Shadma Sharma Deepa Singh Nand K. 《Environmental science and pollution research international》2021,28(30):40275-40287
Environmental Science and Pollution Research - Recently the applications of engineered nanoparticles in the agricultural sector is increased as nano-pesticides, nano-fertilizers, nanocarrier for... 相似文献
6.
van Hullebusch Eric D. Singh Nand K Mal Joyabrata 《Environmental science and pollution research international》2021,28(30):40217-40219
Environmental Science and Pollution Research - 相似文献
7.
D. Swaroopa?RaniEmail author Sharmila?Thirumale Krishna?Nand 《Journal of Material Cycles and Waste Management》2003,5(2):125-129
Consortia were developed for the treatment of corncobs for use as a feedstock in a biogas fermentor. The treatment of corncobs with xylanolytic consortia enhanced the production of methane and biogas. All five consortia developed produced the maximum biogas and methane at a 6% loading rate and 20 days hydraulic retention time (HRT). The maximum biogas yield of 0.59m3/kg volatile solids (VS) with a methane content of 62% was produced with the KK-10 consortium. This was apparently due to a maximum hemicellulose degradation of 88%. 相似文献
8.
Bhavin Mehta Chandra Venkataraman Mani Bhushan Sachchida Nand Tripathi 《Atmospheric environment (Oxford, England : 1994)》2009,43(6):1288-1295
Positive matrix factorization (PMF) was used to identify factors affecting fog formation in Kanpur during the ISRO-GBP land campaign-II (LC-II) in December 2004. PMF predicted factors were validated by contrasting the emission strength of sources in the foggy and clear periods, using a combination of potential source contribution function (PSCF) analysis and quantitative emission inventory information. A time series aerosol chemical data set of 29 days and 12 species was decomposed to identify 4-factors: Secondary species, Biomass burning, Dust and Sea salt. PMF predicted particle mass with a satisfactory goodness-of-fit (slope of 0.83 ± 0.17 and R2 of 0.8), and strong species within 11–12% relative standard deviation. Mean contributions of anthropogenic factors were significantly higher during the foggy period for secondary species (2.9 ± 0.3) and biomass burning (1.2 ± 0.09) compared to the clear period. Local sources contributing to aerosols that mediated fog events at Kanpur, based on emissions in a 200 km × 200 km area around Kanpur city were thermal power plants and transportation (SO2) and biofuel combustion (BC and OM). Regional scale sources influencing emissions during the foggy period, in probable source regions identified by PSCF included thermal power plants, transportation, brick kilns and biofuel combustion. While biofuel combustion and transportation are distributed area sources, individual point sources include coal-fired thermal power plants located in Aligarh, Delhi, Ghaziabad, Jhansi, Kanpur, Rae Bareli and Rupnagar and brick kilns located in Allahabad, Agra, Farrukhabad, Ghaziabad, Kanpur, Ludhiana, Lucknow and Rae Bareli. Additionally, in the foggy period, large areas of probable source regions lay outside India, implying the significance of aerosol incursion from outside India. 相似文献
9.
Khandelwal Kapil Nanda Sonil Boahene Philip Dalai Ajay K. 《Environmental Chemistry Letters》2023,21(5):2619-2638
Environmental Chemistry Letters - The rising issues of global warming due to the rapid use of fossil fuels are calling for sustainable energies such as dihydrogen, thereafter named... 相似文献
10.
Sarker Tumpa R. Nanda Sonil Meda Venkatesh Dalai Ajay K. 《Environmental Chemistry Letters》2023,21(1):231-264
Environmental Chemistry Letters - The demand for bioenergy is increasing due to the diminishing popularity of fossil fuels and rising greenhouse gas emissions. However, according to recent reports,... 相似文献