Modifications of mechanical, thermal, and electrical characteristics of epoxy through dispersion of multi-walled carbon nanotubes in supercritical carbon dioxide

M.G.H. Zaidi,S.K. Joshi,M. Kumar,D. Sharma,A. Kumar,S. Alam,P.L. Sah 한국탄소학회 2013 Carbon Letters Vol.14 No.4

A supercritical carbon dioxide (SCC) process of dispersion of multi-walled carbon nano-tubes (MWCNTs) into epoxy resin has been developed to achieve MWCNT/epoxy com-posites (CECs) with improved mechanical, thermal, and electrical properties. The synthesis of CECs has been executed at a MWCNT (phr) concentration ranging from 0.1 to 0.3 into epoxy resin (0.1 mol) at 1800 psi, 90°C, and 1500 rpm over 1 h followed by curing of the MWCNT/epoxy formulations with triethylene tetramine (15 phr). The effect of SCC treat-ment on the qualitative dispersion of MWCNTs at various concentrations into the epoxy has been investigated through spectra analyses and microscopy. The developed SCC assisted process provides a good dispersion of MWCNTs into the epoxy up to a MWCNT concentra-tion of 0.2. The effects of SCC assisted dispersion at various concentrations of MWCNTs on modificationof mechanical, thermal, dynamic mechanical thermal, and tribological proper-ties and the electrical conductivity of CECs have been investigated.

Comparative electrochemical study of sulphonated polysulphone binded graphene oxide supercapacitor in two electrolytes

Harish Mudila,M.G.H. Zaidi,Sweta Rana,S. Alam 한국탄소학회 2016 Carbon Letters Vol.18 No.-

Sulphonated polysulphone (SPS) has been synthesized and subsequently applied as binder for graphene oxide (GO)-based electrodes for development of electrochemical supercapacitors. Electrochemical performance of the electrode was investigated using cyclic voltammetry in 1M Na2SO4 and 1M KOH solution. The fabricated supercapacitors gave a specific capacitance of 161.6 and 216.8 F/g with 215.4 W/kg and 450 W/kg of power density, in 1M Na2SO4 and 1M KOH solutions, respectively. This suggests that KOH is a better electrolyte than Na2SO4 for studying the electrochemical behavior of electroactive material, and also suggests SPS is a good binder for fabrication of a GO based electrode.

In vivo Acute Cytotoxicity Study of Poly(2-amino ethyl methacrylateco- methylene bis-acrylamide) Magnetic Composite Synthesized in Supercritical CO2

Gunjan Bisht,M. G. H. Zaidi,Biplab KC 한국고분자학회 2018 Macromolecular Research Vol.26 No.7

With magnetic ferrite nanoparticles (FNPs) gaining interest in biotechnological fields and methacrylates being used as synthetic polymer for therapeutics loading and conjugation, we attempt to make novel magnetic composite by supercritical CO2 assisted entrapment of FNPs into in situ synthesized polymeric mesh of 2-amino ethyl methacrylate (AEMA) cross linked with methylene bis-acrylamide (MBA) at90±1 oC and pressure of 1200 psivia 2,2-azobisisobutyronitrile (AIBN) initiated radical polymerization. Particle thus obtained was characterized by using proton nuclear magnetic resonance (1H NMR), X-ray diffraction (XRD), thermal gravimetric-derivative thermogravimetric-differential thermal analysis (TG-DTGDTA), atomic force microscopy (AFM), and vibrating sample magnetometer (VSM). 1H NMR of Copolymer (without FNPs embedded) demonstrated distinct peaks verifying AEMA moieties flanked by MBA moieties with free amino group. Though the particle showed less saturation magnetization than that of as synthesized FNPs, it still maintained similar magnetic profile. AFM results showed average grain size of polymeric magnetic composites (PMCs) to be 80 nm with less agglomeration. TGA results verify the thermal stability of the compound upto 200 oC. In vivo acute cytotoxicity was profiled by administrating four different concentrations of FNPs, Copolymer and PMCs (FNPs embedded) into Sprague Dawley albino rat intraperitonally for 14 days and measuring various hematological, biochemical and serum enzymatic parameters along with histological examinations. Overall, PMCs showed no significance change in these parameters compared to normal saline administered control which signifies biocompatible nature of the composite. Hence, clean synthesis of FNPs embedded biocompatible amino functional magnetic composite has been achieved which holds potential in number of applications like drug loading, enzyme immobilizations, targeted therapy, etc.

Implications of SPION and NBT Nanoparticles upon In Vitro and In Situ Biodegradation of LDPE Film

( Kapri Anil ),( M. G. H. Zaidi ),( Reeta Goel ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.6

Implications of Fullerene-60 upon in-vitro LDPE Biodegradation

( Sah Aditil ),( Anil Kapri ),( M. G H. Zaidi ),( Harshita Negi ),( Reeta Goel ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.5

Biodegradation of e-plastic waste by using indigenous bacteria

( Prasenjit Debbarma ),( Reeta Goel ),( M. G. H. Zaidi ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-

The industrial revolution followed by technological development successively paved the way to a new era in human civilization. In no case, this revolution will decline, thus, making anthropogenic environmental pollution a major global issue. In the present scenario, e-waste accumulation and management is seriously a daunting task that needs to be tackled efficiently. Traditional methods because of their disadvantages have fuelled the use of biological tools to recover the precious metals present in e-waste and to promote the studies of bioleaching and biodegradation processes. Nevertheless, biodegradation studies of and using raw e-plastic waste is scanty in literatures. Therefore, indigenous soil bacteria are explored through enrichment culture approach followed by screening, identification, construction of bacterial consortia and their application for in situ degradation of e-plastic waste. In this study, potential bacteria namely Achromobacter insolitus strain PE2 (MF943156), Acinetobacter nosocomialis strain PE5 (MF943157), Pseudomonas lalkuanensis Novel strain PE8 (MF943158/CP043311), Pseudomonas aeruginosa strain PE10 (MF943159) and Stenotrophomonas pavanii strain PE15 (MF943160) are identified as e-plastic degraders. Their 16S rDNA sequences have been deposited in NCBI GenBank database for their easy accessibility to scientific community. Pseudomonas lalkuanensis sp. nov. strain PE8 (CP043311) was significantly found to be novel culture and its complete genome sequencing has been done and published. Moreover, two new novel bacterial consortia have been developed viz. C-1 and C-2 for biodegradation of e-waste. Nonetheless, one technology/patent which relates to a direct and standardized protocol for e-waste biodegradation in presence of bacterial consortium have recently published by Indian patent office (201811049946) which can be explored further for sustainable management of e-waste. Conclusively, the findings from this research work could be explored for large scale biodegradation of synthetic polymeric e-waste subsequently. Therefore, this study provides degradation and/or fermentation platform for biological recycling of e-waste under in situ conditions. Further, it will enrich the e-plastic degrading bacteria database and this will provide the directive for development of e-plastic degrading bacterial consortia for sustainable strategies.

Electrochemical oxidation-reduction and determination of urea at enzyme free PPY-GO electrode

Harish Mudila,Parteek Prasher,Sweta Rana,Beena Khati,M.G.H. Zaidi 한국탄소학회 2018 Carbon Letters Vol.26 No.-

This manuscript explains the effective determination of urea by redox cyclic voltammetric analysis, for which a modified polypyrrole-graphene oxide (PPY-GO, GO 20% w/w of PPY) nanocomposite electrode was developed. Cyclic voltammetry measurements revealed an effective electron transfer in 0.1 M KOH electrolytic solution in the potential window range of 0 to 0.6 V. This PPY-GO modified electrode exhibited a moderate electrocatalytic effect towards urea oxidation, thereby allowing its determination in an electrolytic solution. The linear dependence of the current vs. urea concentration was reached using square-wave voltammetry in the concentration range of urea between 0.5 to 3.0 μM with a relatively low limit of detection of 0.27 μM. The scanning electron microscopy was used to characterize the morphologies and properties of the nanocomposite layer, along with Fourier transform infrared spectroscopy. The results indicated that the nanocomposite film modified electrode exhibited a synergistic effect, including high conductivity, a fast electron-transfer rate, and an inherent catalytic ability.