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Nand Lal Singh

Bio: Nand Lal Singh is an academic researcher from Banaras Hindu University. The author has contributed to research in topics: Ethanol fermentation & Freundlich equation. The author has an hindex of 4, co-authored 5 publications receiving 62 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the role of TiO2 as the photocatalyst for the degradation of organic pollutants was discussed, and the possible approaches to enhance degradation via the nanoparticle along with existing bottlenecks have been also discussed.
Abstract: Heavy industrialization, specifically in the developing countries, has generated several unwanted environmental pollution. A variety of toxic organic compounds is produced in chemical and petroleum industries, which have resulted in collectively hazardous effects on the environment that needs immediate attention for remediation. Degradation of these pollutants has been tried through the various mechanism, out of which photocatalytic degradation seems to be one of the most promising approaches to reduce environmental pollution specifically in waste water treatment. Photocatalytic degradation has potential for the effective decomposition of organic pollutants due to efficiency to convert light energy into chemical energy. Additionally, the photocatalytic oxidation process is an advanced technique as it offers high degradation and effective mineralization at moderate temperature and specific radiation wavelength. Among various known photocatalysts, TiO2 is regarded as the one of the potential photocatalysts because of its hydrophilic property, high reactivity, reduced toxicity, chemical stability and lower costs. Therefore, the present chapter focuses on the role of TiO2 as the photocatalyst for the degradation of organic pollutants. The general mechanism of degradation of organic pollutants along with properties of TiO2 as the photocatalyst, existing mechanism of degradation via TiO2 was explained. The possible approaches to enhance degradation via TiO2 nanoparticle along with existing bottlenecks have been also discussed.

26 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of gelation temperature and to time on anatase/rutile phase formation had been studied, where two different solvent were used for gelation.
Abstract: Nano TiO2 particles with different phase composition were synthesised using sol-gel method. Two different solvent were used for gelation. Effect of gelation temperature and to time on anatase/rutile phase formation had been studied. Particles crystallinity, crystal size, surface area, pore size had been calculated by x-ray diffraction, Raman spectroscopy, Brunauer-Emmett-Teller (BET) surface area) theory, and transmission electron microscopy analysis. How change in crystal size, surface area, pore size with respect to phase change also has been studied. Arsenate and arsenite removal by TiO2 particles of different phase compositions had been investigated by atomic absorption spectroscopy. Some parameters such as the contact time and the pH of the solution, which could affect the magnitude of adsorption, were examined. Sorption data have been interpreted in terms of the Freundlich and Langmuir equations. [Supplemental materials are available for this article. Go to the publisher's online edition of the Jour...

17 citations

Journal Article
TL;DR: Optimization of a suitable process for whole cell immobilization of Kluyveromyces thermtolerons in calcium alginate, coconut coir, bagasse, and jute stick for ethanol production in a packed bed bioreactor is presented.
Abstract: Optimization of a suitable process for whole cell immobilization of Kluyveromyces thermtolerons in calcium alginate, coconut coir, bagasse, and jute stick for ethanol production in a packed bed bioreactor is presented. Specific ethanol production of immobilized cells for jute stick was maximum. Cell to carrier ratio (9: 10) was optimum.

15 citations

Journal ArticleDOI
TL;DR: This study presents the utility of multivariate statistical techniques for evaluation of the proposed interactions and effective future monitoring of potential sites in the Indo-Gangetic plain of northern India.
Abstract: Multivariate statistical techniques were employed for monitoring of ground-surface water interactions in rivers. The river Varuna is situated in the Indo-Gangetic plain and is a small tributary of river Ganga. The study area was monitored at seven sampling sites for 3 years (2010–12), and eight physio-chemical parameters were taken into account for this study. The data obtained were analysed by multivariate statistical techniques so as to reveal the underlying implicit information regarding proposed interactions for the relevant area. The principal component analysis (PCA) and cluster analysis (CA), and the results of correlations were also studied for all parameters monitored at every site. Methods used in this study are essentially multivariate statistical in nature and facilitate the interpretation of data so as to extract meaningful information from the datasets. The PCA technique was able to compress the data from eight to three parameters and captured about 78.5 % of the total variance by performing varimax rotation over the principal components. The varifactors, as yielded from PCA, were treated by CA which grouped them convincingly into three groups having similar characteristics and source of contamination. Moreover, the loading of variables on significant PCs showed correlations between various ground water and surface water (GW-SW) parameters. The correlation coefficients calculated for various physiochemical parameters for ground and surface water established the correlations between them. Thus, this study presents the utility of multivariate statistical techniques for evaluation of the proposed interactions and effective future monitoring of potential sites.

14 citations

01 May 2011
TL;DR: This paper presents inhibitory effect of ethanol on growth of cells and ethanol production, and confirms both reversible and irreversible inhibition of cells by ethanol.
Abstract: This paper presents inhibitory effect of ethanol on growth of cells and ethanol production. A linear fall was observed of survival (%) of Kluyveromyces Thermotolerans cells with time. Change in death rate constant of cells beyond certain range of ethanol concentration was due to shift in mechanism of cells inhibition. Pronounced inhibitory effect was observed at higher ethanol concentrations in broth. Decrease in optimum temperature for growth of cells was found with added ethanol concentration. This also confirms more inhibitory effect of product on microorganism at higher temperature. This study confirms both reversible and irreversible inhibition of cells by ethanol.

2 citations


Cited by
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Journal ArticleDOI
TL;DR: The results show that proper modification of the carrier with cellulase hydrolysis was suitable for cell immobilization and increased the immobilized cell concentration, and disrupted the sleek surface to become rough and porous, which enhanced ethanol production.
Abstract: The aim of the present study was to examine ethanol production from concentrated food waste hydrolysates using whole cells of S. cerevisiae immobilized on corn stalks. In order to improve cell immobilization efficiency, biological modification of the carrier was carried out by cellulase hydrolysis. The results show that proper modification of the carrier with cellulase hydrolysis was suitable for cell immobilization. The mechanism proposed, cellulase hydrolysis, not only increased the immobilized cell concentration, but also disrupted the sleek surface to become rough and porous, which enhanced ethanol production. In batch fermentation with an initial reducing sugar concentration of 202.64 ± 1.86 g/l, an optimal ethanol concentration of 87.91 ± 1.98 g/l was obtained using a modified corn stalk-immobilized cell system. The ethanol concentration produced by the immobilized cells was 6.9% higher than that produced by the free cells. Ethanol production in the 14th cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in an immobilized cell reactor, the maximum ethanol concentration of 84.85 g/l, and the highest ethanol yield of 0.43 g/g (of reducing sugar) were achieved at hydraulic retention time (HRT) of 3.10 h, whereas the maximum volumetric ethanol productivity of 43.54 g/l/h was observed at a HRT of 1.55 h.

49 citations

Journal ArticleDOI
TL;DR: In this paper, extra hardened beads (EHB) immobilized with Saccharomyces cerevisiae GSE1618 was employed for ethanol fermentation using rice straw enzymatic hydrolysate in a packed bed reactor (PBR).

34 citations

Journal ArticleDOI
TL;DR: In this article, the authors used Pulsed Laser Ablation in Liquid (PLAL) followed by microwave irradiation to synthesize vertically aligned MoS2 nanosheets, RBIHM and HBTiO2 nanoparticles.
Abstract: In this research, Black TiO2 (BTiO2), which consisted of Rutile Based Inorganic Hollow Microspheres (RBIHM) and hydrogenated anatase TiO2 nanoparticles, decorated with MoS2 nanosheets (HBTiO2/RBIHM-MoS2 photocatalyst) was synthesized using Pulsed Laser Ablation in Liquid (PLAL) followed by microwave irradiation. Formation of vertically aligned MoS2 nanosheets, RBIHM and HBTiO2 nanoparticles were confirmed by different characterization techniques. The spectroscopic analysis revealed phase transitions in HBTiO2/RBIHM nano and microstructures along with the formation of different crystal disorders such as amorphous layers, oxygen vacancies, trivalent titanium ions and formation of molybdenum oxide (MoO3-x) in MoS2. In addition, MoS2 films in HBTiO2/RBIHM-MoS2 nanocomposite showed both Mo5+ and Mo6+ oxidation state, which was inferred that these films have a p-type conductive behavior. Furthermore, the interconnected layers of MoS2 nanosheets led to the formation of a porous like 3D nanostructure in HBTiO2/RBIHM-MoS2, which could significantly improve its photocatalytic performance. Arsenite photooxidation efficiencies of 70.3% and 96.6% and arsenate adsorption capacities of 1600 and 5200 μg g−1 were obtained for HBTiO2/RBIHM and HBTiO2/RBIHM-MoS2, respectively. The synergetic effects originated from making RBIHM-HBTiO2, RBIHM-MoS2 and MoS2–HBTiO2 heterojunctions along with the surface and morphology modification in MoS2 NSs and HBTiO2/RBIHM can explain the nanocomposite superior photocatalytic performance. The present work can trigger a broad interest in the cost-effective nanoarchitecture of visible light driven heterostructured photocatalysts.

34 citations

Journal ArticleDOI
TL;DR: Results show that Fe3O4–TiO2 NPs are promising adsorbents with an advantage of magnetic separation.
Abstract: A magnetically separable nanomaterial Fe3O4–TiO2 was synthesized and characterized which was subsequently used for the removal of arsenic (V) from aqueous solutions. The surface morphology, magnetic properties, crystalline structure, thermal stability and Brunauer–Emmet–Teller surface area of the synthesized Fe3O4–TiO2 nanoparticles (NPs) are characterized by scanning electron microscope and high-resolution transmission electron microscope, vibrating sample magnetometry, X-ray diffractometer, thermogravimetric analysis and multi point function surface area analyzer. The saturation magnetization of Fe3O4–TiO2 NPs was determined to be 50.97 emu/g, which makes them superparamagnetic. The surface area of Fe3O4–TiO2 NPs was as much as 94.9 m2/g. The main factors affecting adsorption efficiency, such as solution pH, reaction time, initial As(V) concentration and adsorbent concentration are investigated. When the adsorption isotherms were analyzed by the Langmuir, Freundlich and Dubinin-Radushkevich mode...

32 citations

Journal ArticleDOI
TL;DR: In this paper, a continuous ethanol fermentation of concentrated food waste hydrolysates has been studied in an immobilized cell reactor with beads of calcium-alginate containing immobilized Saccharomyces cerevisiae H058 at temperature 30 °C and pH 5.0.
Abstract: BACKGROUND: Continuous ethanol fermentation of concentrated food waste hydrolysates has been studied. The process was carried out in an immobilized cell reactor with beads of calcium-alginate containing immobilized Saccharomyces cerevisiae H058 at temperature 30 °C and pH 5.0. RESULTS: The total residual sugar decreased with increase of hydraulic retention time (HRT) under various reducing sugar concentrations. Ethanol production by immobilized cells increased with increase in HRT, regardless of the substrate concentrations employed. The highest ethanol concentration of 89.28 g L−1 was achieved at an HRT of 5.87 h and reducing sugar concentration of 200 g L−1. At an HRT of 1.47 h, the maximum volumetric ethanol productivity of 49.88 g L−1 h−1 and the highest ethanol yield of 0.48 g g−1 were achieved at reducing sugar concentration of 160 and 200 g L−1, respectively. The difference between the fresh and the 30-day Ca–alginate immobilized cell was also shown by scanning electronic micrographs of beads taken from their outer and inner surfaces. CONCLUSIONS: Continuous ethanol production from concentrated food waste hydrolysates using immobilized yeast cells is promising in view of the high ethanol productivity obtained at relatively high conversion and excellent reactor stability. Copyright © 2011 Society of Chemical Industry

32 citations