Papers by Mithilesh Yadav
Bioprocessing is a natural, safe, and effective way for food manufacturers to create products suc... more Bioprocessing is a natural, safe, and effective way for food manufacturers to create products such as cheese, yogurt, bread, wine, and beer. Bioprocessing uses living organisms and their components in the creation of new products. They used microbes and enzymes in bioprocessing technology provided best results under mild conditions such as neutral pH, normal atmospheric pressure, and temperatures close to room temperature. Therefore, bioprocessing can save a lot of energy in food industry—especially when they act as an alternative to heating products to high temperatures. Bioprocessing can also enhance taste and texture. Also, the microbes used in bioprocessing are biodegradable—reducing the carbon footprint of food production even further. The conventional food bioprocessing methods such as drying, fermentation, salting, and various forms of cooking, including roasting, frying, smoking, steaming, and oven baking developed the quality and flavor of the foods but they are unable to p...
Gellan Gum (GG) was modified with N-vinyl Formamide (NVF) through PDP/Ag + redox system initiated... more Gellan Gum (GG) was modified with N-vinyl Formamide (NVF) through PDP/Ag + redox system initiated graft copolymerization in a thermostatic water bath at 35°C under nitrogen atmosphere. The highest percentage of grafting (186%) and the lowest homopolymer content (22.2%) were achieved through a systematic optimization of the polymerization variables, including reaction time, temperature, and concentration of PDP, Ag + , NVF and the gum. Evidence of grafting was examined by comparing FTIR spectra. The optimally prepared graftcopolymer (GG-g-NVF) was also characterized thermally and morphologically. The GG-g-NVF product was saponified using sodium hydroxide aqueous solution to prepare a partially hydrolyzed graft copolymer based superabsorbent, H-GG-g-NVF. The effect of dewatering agent of H-GG-g-NVF on water absorbency has been studied. The percentage swelling of H-GG-g-NVF in various ionic salt (NaCl, CaCl2 and AlCl3) solutions were investigated. In addition, the percentage swelling c...
The synthesis of graft copolymer (partially carboxymethylated guar gum-g-N-vinyl-2-pyrrolidone) i... more The synthesis of graft copolymer (partially carboxymethylated guar gum-g-N-vinyl-2-pyrrolidone) is carried out in nitrogen atmosphere using potassium peroxymonosulphate and glycolic acid as redox system. The effect of reaction variables including the concentration of N-vinyl-2-pyrrolidone (8 × 10−2 −2 −3 −3 −3 −3 vailable online 28 October 2010
International Journal of Biochemistry, Biophysics & Molecular Biology
The present paper reports the modification of guar gum through the grafting of 2-acrylamidoglycol... more The present paper reports the modification of guar gum through the grafting of 2-acrylamidoglycolic acid by free radical polymerization using an efficient potassium peroxydiphosphate/thioacetamide redox system in nitrogen atmosphere. The reaction conditions for maximum grafting have been optimized by varying the reaction variables including the concentration of 2-acrylamidoglycolic acid (5.3×10-2 mol dm-3), potassium peroxydiphosphate (1.2×10-2 mol dm-3), thioacetamide (TA) (2×10-3 mol dm-3), sulphuric acid (4×10-3 mol dm-3), guar gum (1 g dm −3) along with time duration (150 min) and temperature (35°C). Water swelling capacity and flocculation and studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.
Toxin Reviews
This study focused on the synthesis of copper oxide (CuO) nanoparticles by chemical precipitation... more This study focused on the synthesis of copper oxide (CuO) nanoparticles by chemical precipitation method for the uptake of divalent nickel ions from aqueous media. The adsorption capacity was 15.4 ...
Nanomaterials
Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3... more Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3, respectively, were prepared using auto-combustion method. Binary nanohybrids, ZrO2@rGO and ZCO-2@rGO (rGO = reduced graphene oxide), and ternary nanohybrids, ZrO2@rGO@MoS2 and ZCO-2@rGO@MoS2, have been prepared with an anticipation of a fruitful synergic effect of rGO, MoS2, and cerium-doped zirconia on the tribo-activity. Tribo-activity of these additives in paraffin oil (PO) has been assessed by a four-ball lubricant tester at the optimized concentration, 0.125% w/v. The tribo-performance follows the order: ZCO-2@rGO@MoS2 > ZrO2@rGO@MoS2 > ZCO-2@rGO > ZrO2@rGO > MoS2 > ZrO2 > rGO > PO. The nanoparticles acting as spacers control restacking of the nanosheets provided structural augmentation while nanosheets, in turn, prevent agglomeration of the nanoparticles. Doped nanoparticles upgraded the activity by forming defects. Thus, the results acknowledge the synergic ...
Nanomaterials, Apr 8, 2020
Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3... more Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3, respectively, were prepared using auto-combustion method. Binary nanohybrids, ZrO 2 @rGO and ZCO-2@rGO (rGO = reduced graphene oxide), and ternary nanohybrids, ZrO 2 @rGO@MoS 2 and ZCO-2@rGO@MoS 2, have been prepared with an anticipation of a fruitful synergic effect of rGO, MoS 2 , and cerium-doped zirconia on the tribo-activity. Tribo-activity of these additives in paraffin oil (PO) has been assessed by a four-ball lubricant tester at the optimized concentration, 0.125% w/v. The tribo-performance follows the order: ZCO-2@rGO@MoS 2 > ZrO 2 @rGO@MoS 2 > ZCO-2@rGO > ZrO 2 @rGO > MoS 2 > ZrO 2 > rGO > PO. The nanoparticles acting as spacers control restacking of the nanosheets provided structural augmentation while nanosheets, in turn, prevent agglomeration of the nanoparticles. Doped nanoparticles upgraded the activity by forming defects. Thus, the results acknowledge the synergic effect of cerium-doped zirconia and lamellar nanosheets of rGO and MoS 2. There is noncovalent interaction among all the individuals. Analysis of the morphological features of wear-track carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in PO and its formulations with various additives is consistent with the above sequence. The energy dispersive X-ray (EDX) spectrum of ZCO-2@rGO@MoS 2 indicates the existence of zirconium, cerium, molybdenum, and sulfur on the wear-track, confirming, thereby, the active role played by these elements during tribofilm formation. The X-ray photoelectron spectroscopy (XPS) studies of worn surface reveal that the tribofilm is made up of rGO, zirconia, ceria, and MoS 2 along with Fe 2 O 3 , MoO 3 , and SO 4 2− as the outcome of the tribo-chemical reaction.
International Journal of Biochemistry, Biophysics & Molecular Biology, 2017
The present paper reports the modification of guar gum through the grafting of 2-acrylamidoglycol... more The present paper reports the modification of guar gum through the grafting of 2-acrylamidoglycolic acid by free radical polymerization using an efficient potassium peroxydiphosphate/thioacetamide redox system in nitrogen atmosphere. The reaction conditions for maximum grafting have been optimized by varying the reaction variables including the concentration of 2-acrylamidoglycolic acid (5.3×10-2 mol dm-3), potassium peroxydiphosphate (1.2×10-2 mol dm-3), thioacetamide (TA) (2×10-3 mol dm-3), sulphuric acid (4×10-3 mol dm-3), guar gum (1 g dm −3) along with time duration (150 min) and temperature (35°C). Water swelling capacity and flocculation and studies of synthesized graft copolymer have been performed with respect to the parent polymer. The graft copolymer has been characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.
Polymers
In this study, green composite films based on cellulose nanocrystal/chitosan (CNC/CS) were fabric... more In this study, green composite films based on cellulose nanocrystal/chitosan (CNC/CS) were fabricated by solution casting. FTIR, XRD, SEM, and TEM characterizations were conducted to determine the structure and morphology of the prepared films. The addition of only 4 wt.% CNC in the CS film improved the tensile strength and Young’s modulus by up to 39% and 78%, respectively. Depending on CNC content, the moisture absorption decreased by 34.1–24.2% and the water solubility decreased by 35.7–26.5% for the composite films compared with neat CS film. The water vapor permeation decreased from 3.83 × 10−11 to 2.41 × 10−11 gm−1 s−1Pa−1 in the CS-based films loaded with (0–8 wt.%) CNC. The water and UV barrier properties of the composite films showed better performance than those of neat CS film. Results suggested that CNC/CS nanocomposite films can be used as a sustainable packaging material in the food industry.
Polymers
Polyamide 6 (PA6)/poly(vinylidene fluoride) (PVDF) blend-based nanocomposites were successfully p... more Polyamide 6 (PA6)/poly(vinylidene fluoride) (PVDF) blend-based nanocomposites were successfully prepared using a twin screw extruder. Carbon nanotube (CNT) and organo-montmorillonite (30B) were used individually and simultaneously as reinforcing nanofillers for the immiscible PA6/PVDF blend. Scanning electron micrographs showed that adding 30B reduced the dispersed domain size of PVDF in the blend, and CNT played a vital role in the formation of a quasi-co-continuous PA6-PVDF morphology. Transmission electron microscopy observation revealed that both fillers were mainly located in the PA6 matrix phase. X-ray diffraction patterns showed that the presence of 30B facilitated the formation of γ-form PA6 crystals in the composites. Differential scanning calorimetry results indicated that the crystallization temperature of PA6 increased after adding CNT into the blend. The inclusion of 30B retarded PA6 nucleation (γ-form crystals growth) upon crystallization. The Young’s and flexural modu...
Polymer
Abstract Carbon nanotube (CNT) was incorporated into the miscible poly(lactic acid)/poly(ethylene... more Abstract Carbon nanotube (CNT) was incorporated into the miscible poly(lactic acid)/poly(ethylene oxide) (PLA/PEO) blend to successfully fabricate biodegradable nanocomposites. Scanning electron microscope images revealed the well dispersion of as-received CNT within the blend through the melt-mixing process. Thermogravimetric analysis showed that the CNT significantly improved the thermal stability of the blend (up to 68 °C increase at 3-phr CNT addition compared to the blend at 10 wt% loss) in air. Differential scanning calorimetry data showed the nucleation effect of CNT on the crystallization of individual PLA and PEO; the presence of CNT increased the melting temperature of PLA crystals. Measurement of rheological behavior confirmed the formation of CNT (pseudo-)network structure in the composites. The impact strength of the composite with 3-phr CNT loading was three times higher than that of the blend. The electrical resistivity of the blend reduced by up to nine orders of magnitude at 3-phr CNT loading. The electrical and rheological percolation thresholds were both achieved at 1-phr CNT loading for the nanocomposites.
Nanomaterials
Eco-friendly cellulose nanocrystal/silver/alginate (CNC/Ag/Alg) bionanocomposite films were succe... more Eco-friendly cellulose nanocrystal/silver/alginate (CNC/Ag/Alg) bionanocomposite films were successfully prepared by blending of CNC with Ag/Alg solution. The CNC was fabricated from cellulose microcrystal (CMC) by acid hydrolysis method. The Ag nanoparticles (AgNPs) were generated by using Alg as a reducing agent through hydrothermal process. AgNPs-included composite films showed characteristic plasmonic effect of the AgNPs with the maximum absorption at 491 nm and they also showed high ultraviolet (UV) barrier properties. The CNC/Ag/Alg composite films were analyzed by using scanning electron microscopy, transmission electron microscopy, optical microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction technique. Depending on the type of nanofillers, tensile strength of the composite films increased by 39–57% and water vapor permeation decreased by 17–36% compared with those of the neat Alg films. The Ag/Alg and CNC/Ag/Alg films showed brown color as detected from...
Nanomaterials
In this study, a graphene nanoplatelet (GNP) was used as a reinforcing filler to prepare poly(vin... more In this study, a graphene nanoplatelet (GNP) was used as a reinforcing filler to prepare poly(vinylidene fluoride) (PVDF)/high density polyethylene (HDPE) blend-based nanocomposites through a melt mixing method. Scanning electron microscopy confirmed that the GNP was mainly distributed within the PVDF matrix phase. X-ray diffraction analysis showed that PVDF and HDPE retained their crystal structure in the blend and composites. Thermogravimetric analysis showed that the addition of GNP enhanced the thermal stability of the blend, which was more evident in a nitrogen environment than in an air environment. Differential scanning calorimetry results showed that GNP facilitated the nucleation of PVDF and HDPE in the composites upon crystallization. The activation energy for non-isothermal crystallization of PVDF increased with increasing GNP loading in the composites. The Avrami n values ranged from 1.9–3.8 for isothermal crystallization of PVDF in different samples. The Young’s and fle...
Carbohydrate Polymers
In this work, κ-carrageenan bionanocomposite films were prepared by solution casting of a mixture... more In this work, κ-carrageenan bionanocomposite films were prepared by solution casting of a mixture of κ-carrageenan, glycerol, and various amounts of cellulose nanocrystals (CNCs, 0-9 wt.%). The structure and morphology of the bionanocomposite films were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. Compared with κ-carrageenan films, the κ-carrageenan bionanocomposite films showed better mechanical and barrier properties (water and UV) and thermal stability. The water contact angle increased from 23.30° to 71.80° and the water vapor permeation decreased from 8.93 gm-1 s-1 Pa-1 to 4.69 × 10-11 gm-1 s-1 Pa-1 in the κ-carrageenan films loaded with 9-7 wt.% CNCs, respectively. The tensile strength and elongation at break of the films increased from 38.33 ± 3.79 MPa to 52.73 ± 0.70 MPa and from 21.50 ± 3.72% to 28.27 ± 2.39%, respectively, after CNC loading increased from 0 wt.% to 7.0 wt.%. These results indicated that the κ-carrageenan nanocomposite films have potential applications in food packaging.
Composites Part B: Engineering
Abstract Present article reports a facile synthesis of high-performance cross-linked antimicrobia... more Abstract Present article reports a facile synthesis of high-performance cross-linked antimicrobial oleo-polyurethane nanocomposites (PUCs) using graphite (Gr), graphene oxide (GO) and reduced graphene oxide (RGO) via in-situ polymerization. The synergistic effect of oleo-precursor and in-situ polymerization facilitated the formation of covalent/noncovalent interactions between GO/RGO and matrix that maximized their reinforcing property and inhibited their leaching. These interactions developed the self-engineered network with random distributions of GO/RGO within the matrix, which enhanced the tensile strength, degree of crosslinking while reducing the water uptake of PUCs. The antimicrobial studies confirmed the permanent biocidal effect of GO and RGO PUCs against both classes of bacteria via contact-killing.
Carbohydrate Polymers, 2010
Carbohydrate Polymers, Mar 6, 2010
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Papers by Mithilesh Yadav