排序方式: 共有45条查询结果,搜索用时 359 毫秒
41.
S. Sivakumar Y. C. Song I. S. Park S. H. Cho C. Y. Lee Boo Gil Kim 《Environmental monitoring and assessment》2010,165(1-4):449-460
Heavy metal accumulation (Cu, Zn, Ni, and Pb) in common marine macroalga, Acrosorium uncinatum under nutrient (phosphate and nitrate) enriched (experiment 1) and starved (experiment 2) conditions over a short exposure period (12 h) were examined in this study. Control was maintained in seawater contained nutrient solution without addition of metals and in seawater alone for experiment 1 and 2, respectively. Among the four metals studied, the accumulation of Zn, Ni, and Pb was considerably lower than Cu. The accumulation factor for all metals varies greatly in different nutrient concentrations, but it increases as the exposure of metal concentration decreases in both the experiments. The results of the present findings established that this macroalga is an accumulator of metals Cu, Zn, Ni, and Pb and have the potential to accumulate these metals even in a short time exposure period (12 h). Even though metal accumulation by A. uncinatum largely depends on the available concentration in the medium, nutrients like phosphate and nitrate can affect the accumulation significantly. 相似文献
42.
Bhumireddy Jayachandra Mallineni Sreekanth Kumar Nuvvula Sivakumar 《Environmental science and pollution research international》2021,28(2):1275-1277
Environmental Science and Pollution Research - The pandemic outbreak of coronavirus disease (COVID-19) created a significant impact on the oral healthcare profession, and dentists are reported to... 相似文献
43.
Ayodele Joseph Adesin Kanike Raghavendra Kumar Venkataraman Sivakumar Derek Griffith 《环境科学学报(英文版)》2014,26(12):2459-2474
The present study uses the data collected from Cimel Sunphotometer of Aerosol Robotic Network(AERONET) for the period from January to December, 2012 over an urban site,Pretoria(PTR; 25.75°S, 28.28°E, 1449 m above sea level), South Africa. We found that monthly mean aerosol optical depth(AOD, τa) exhibits two maxima that occurred in summer(February) and winter(August) having values of 0.36 ± 0.19 and 0.25 ± 0.14,respectively, high-to-moderate values in spring and thereafter, decreases from autumn with a minima in early winter(June) 0.12 ± 0.07. The Angstrom exponents(α440–870) likewise,have its peak in summer(January) 1.70 ± 0.21 and lowest in early winter(June) 1.38 ± 0.26,while the columnar water vapor(CWV) followed AOD pattern with high values(summer) at the beginning of the year(February, 2.10 ± 0.37 cm) and low values(winter) in the middle of the year(July, 0.66 ± 0.21 cm). The volume size distribution(VSD) in the fine-mode is higher in the summer and spring seasons, whereas in the coarse mode the VSD is higher in the winter and lower in the summer due to the hygroscopic growth of aerosol particles.The single scattering albedo(SSA) ranged from 0.85 to 0.96 at 440 nm over PTR for the entire study period. The averaged aerosol radiative forcing(ARF) computed using SBDART model at the top of the atmosphere(TOA) was- 8.78 ± 3.1 W/m2, while at the surface it was- 25.69 ± 8.1 W/m2 leading to an atmospheric forcing of + 16.91 ± 6.8 W/m2, indicating significant heating of the atmosphere with a mean of 0.47 K/day. 相似文献
44.
Krishnasamy Lakshmi Krishna Kadirvelu Subpiramaniyam Sivakumar 《Environmental science and pollution research international》2022,29(36):54282-54291
Environmental Science and Pollution Research - Polyacrylonitrile (PAN)-based-modified zinc oxide (ZnO) nanofibers were synthesized by using electrospinning and hydrothermal techniques. The... 相似文献
45.
Jayakumar Venkatachalam Govindaradjane Soupramaniane Rajamohan Natarajan Rajasimman Manivasagan 《Environmental science and pollution research international》2022,29(28):41909-41922
Environmental Science and Pollution Research - In this research work, the biosorption potential of brown algae, Sargassum polycystum, was investigated for the removal of toxic metals, cadmium (Cd)... 相似文献