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51.
Removal efficiency of fluoride by novel Mg-Cr-Cl layered double hydroxide by batch process from water 总被引:1,自引:0,他引:1
Sandip Mandal Swagatika Tripathy Tapswani Padhi Manoj Kumar Sahu Raj Kishore Patel 《环境科学学报(英文版)》2013,25(5):993-1000
The fluoride ion removal from aqueous solution using synthesized Mg-Cr-Cl layered double hydroxide has been reported.Mg-Cr-Cl was characterized by X-ray powder diffraction,Fourier-transform infrared,thermo-gravimetric analysis,differential thermal analysis,and scanning electron microscope.Adsorption experiments were carried out in batch mode as a function of adsorption dosages,contact time,pH,and initial fluoride concentration to get optimum adsorption capacity.The adsorption kinetic study showed that the adsorption process followed first order kinetics.The fluoride removal was 88.5% and 77.4% at pH 7 with an adsorbent dose of 0.6 g/100 mL solution and initial fluoride concentration of 10 mg/L and 100 mg/L,respectively.The equilibrium was established at 40 min.Adsorption experiment data were fitted well with Langmuir isotherm with R 2 = 0.9924.Thermodynamic constants were also measured and concluded that the adsorption process was spontaneous and endothermic in nature.The removal percentage decreased slowly with increasing pH.This process is suitable for industrial effluents.The regeneration of the material is not possible. 相似文献
52.
Mayank Varun Rohan D��Souza Devendra Kumar Manoj S. Paul 《Environmental monitoring and assessment》2011,178(1-4):373-381
Toxicity of lead in soil is well documented and established. Phytoremediation has gained attention as a cheap, easily applicable, and eco-friendly clean-up technology. Chemical methods are used to assess exact levels and type of pollutants but heavy metal content in soil can also be evaluated indirectly by estimation of phytotoxicity levels using bioassays. Plant bioassays through fast germinating cereals can indicate not only the level of pollution and its effects on growth and survival but also the progress of phytoremediation process. The performance of barley Hordeum vulgare L. seedlings as bioassay for assessment of changes in the levels of lead (Pb) at three concentrations, i.e., 300 (T1), 600 (T2), and 1,200 ppm (T3) in the soil was evaluated while testing the efficiency of Crinum asiaticum L. as a phytoremedial tool. At the first assessment, i.e., 30 DAT (days after treatment) shoot and root lengths of seedlings decreased with increasing concentrations of Pb. As the study progressed, a decrease in levels of Pb was accompanied by better germinability and growth of barley. At 120 DAT seedling growth in all the treatments were comparable to control. In T1, T2, and T3 soils, 74.5%, 83.7%, and 91.2% reduction in lead content was observed at 120 DAT. Highly significant correlations between decreasing pollutant (Pb) content in the soil, seed germination, and seedling growth of barley H. vulgare were found. The differences in root and shoot length as well as overall growth pattern are indicative of the suitability of barley as a bio-monitoring tool. 相似文献
53.
Baby Ruby Nixon Peter Daniel Kumar Nallapaneni Manoj Subathra M. S. P. Ananthi Nallamuthu 《Environmental science and pollution research international》2022,29(1):371-404
Environmental Science and Pollution Research - Dye-sensitized solar cells (DSSC) constructed using natural dyes possess irreplaceable advantages in energy applications. The main reasons are its... 相似文献
54.
Nanoceuticals are pharmaceuticals or natural supplements, also known as nutraceuticals, designed using nanotechnologies. Benefits of nanoceuticals as therapeutics include better aqueous solubility and permeability, and reduced side effects. Nanoceuticals are designed using a wide variety of formulations such as nanoemulsions, micelles, nanoparticles, nanocapsules, nanocochleates and nanocrystals. The article is a snapshot of the impact of nanotechnology on nutrition and food; it discusses regulations and risks. 相似文献
55.
P. Manoj Kumar K. Mylsamy Karthick Alagar K. Sudhakar 《International Journal of Green Energy》2020,17(13):872-883
ABSTRACT This work explores the opportunities to address the setback in thermal energy storage of solar-based water heaters by uniting it with a suitable hybrid-nano composite phase change material (HNCPCM) in a static mode of operation. The experiments were conducted on a natural circulation all-glass evacuated solar water heating system (AGSWH). The investigation was steered in five cases such that the first case without any phase change material (PCM), the second with pure paraffin as PCM, and remaining three cases with three different mass percentage of HNCPCMs (0.5%, 1.0%, and 2.0% mass fraction of hybrid nanoparticles within PCM) in real-time solar exposure. The system was analyzed based on the first and second law of thermodynamics to assess the performance in all the five cases. Erstwhile, the hybrid nanoparticles were prepared by blending equal mass of SiO2 and CeO2 nanoparticles and characterized to gauge its thermal storage properties. The achieved results substantiated that the thermal conductivity had boosted with the accumulation of hybrid nanoparticles within the paraffin matrix, and maximum enhancement of 65.56% was attained with 2.0% mass fraction. The first law and second law investigations revealed that the incorporation of hybrid-nano composites improved the energy and exergy content of the system, distinctly. Among the experimented cases, HNCPCM with 1.0 mass% of hybrid nanoparticles remarkably yielded a better result of 19.4% and 1.28% improvement in energy and exergy efficiencies, respectively. Besides, it evidenced the necessity of choosing the right quantity of nanoparticles for achieving better overall results. 相似文献
56.
Kumar Atul Singh Sunil Pramanik Malay Chaudhary Shairy Maurya Ashwani Kumar Kumar Manoj 《Environment, Development and Sustainability》2022,24(3):3723-3761
Environment, Development and Sustainability - Watersheds in the subtropical Himalayan basins are highly prone to land degradation due to deforestation, landslides, intensive agriculture, population... 相似文献
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58.
Semi-parametric Bayesian density estimation using ranked set sample in the presence of ranking error
In this paper, we propose a Bayesian method to estimate the underlying density function of a study variable Y using a ranked set sample in which an auxiliary variable X is used to rank the sampling units. The amount of association between X and Y is not known, resulting in an unknown degree of ranking error. We assume that (X, Y) follows a Morgenstern family of distributions. The study variable Y is assumed to have a parametric distribution, with the distribution of the parameters having a Dirichlet process prior. A Markov chain Monte Carlo procedure is developed to obtain a Bayesian estimator of the desired density function as well as of the ranking error. A simulation study is used to evaluate the performance of the proposed method. An example from forestry is used to illustrate a real-life application of the proposed methodology. 相似文献
59.
Neupane Ramesh K C Anup Aryal Manoj Rijal Kedar 《Environment, Development and Sustainability》2021,23(11):15897-15920
Environment, Development and Sustainability - This study was conducted with an aim to assess the status of ecotourism in terms of tourism demand, tourist characteristics, and strength,... 相似文献
60.
Varun M D'Souza R Pratas J Paul MS 《Environmental science and pollution research international》2012,19(1):269-281