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Srivastva A.N.,Meerut College | Singh N.P.,Meerut College | Shriwastaw C.K.,Meerut College
Research on Chemical Intermediates | Year: 2017

Reaction between hydrazine derivative ligands (HrzE) or (HrzB) and chromium salt in 1:2 (metal:ligand) molar ratio yielded monometallic trivalent coordination compounds with general formula [Cr(HrzE)2X2]X and [Cr(HrzB)2X2]X, where (HrzE) = hydrazine carboxylic acid ethyl ester, (HrzB) = hydrazine carboxylic acid tert-butyl ester, and X = Cl−, Br− or F−. Elemental analysis, conductivity measurements, magnetic moment measurements, and various spectroscopic techniques, viz. infrared, ultraviolet–visible, and electrospray ionization mass spectrometry, were applied to illustrate the structure and composition of the coordination compounds. Analytic and conductivity results were consistent with 1:1 electrolytic behavior and the proposed formulas of the coordination compounds. Electronic absorption data and magnetic moment parameters indicated octahedral geometry surrounding the metal ion in the coordination compounds. The in vitro antimicrobial behavior of the ligands and coordination compounds was screened using four bacterial strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Salmonella typhi) and two fungal strains (Candida parapsilosis and Saccharomyces cerevisiae). The results indicated improved activity of the coordination compounds compared with the free ligands against the studied bacteria and fungi. © 2017 Springer Science+Business Media Dordrecht

The effect of total solar eclipse on atmospheric conductivities has been studied. Continuous measurements of both types of positive and negative electrical conductivities and some meteorological parameters in conjunction with the total solar eclipse of 22 July, 2009 were made from 21 to 23 July, 2009 at Roorkee (29°52′ N, 77°53′ E, 275 m above sea level). Roorkee observed 90% maximum obscurity of eclipse since it was close to the path of totality. The event started from 05:28 AM IST and ended at 07:42 AM IST with the total eclipse at 06:30 AM IST Considerable increase of both positive and negative conductivities were recorded during the eclipse with respect to those made on any other day. Increase in relative humidity and decrease in temperature were also observed during the period of eclipse. © 2010 IACS.

Malik P.,National Institute of Technology Jalandhar | Raina K.K.,Thapar University | Bubnov A.,ASCR Institute of Physics Prague | Chaudhary A.,National Institute of Technology Jalandhar | Singh R.,Meerut College
Thin Solid Films | Year: 2010

Electro-optic and dielectric studies have been carried out on two ferroelectric liquid crystalline materials: namely, the commercial mixture possessing low spontaneous polarization and pure material with high spontaneous polarization on cells with planar alignment. The calculated values of spontaneous polarization, response time and rotational viscosity were found ∼ 240 nC/cm2, 20 nC/cm2, 1600 μs, 500 μs, 230 kg/ms and 19 kg/ms for high and low polarization ferroelectric liquid crystalline materials, respectively. For the ferroelectric liquid crystal with high polarization, the effect of temperature, frequency and bias field on the dielectric properties have been studied and the obtained results were compared to those obtained on the ferroelectric liquid crystalline mixture with low spontaneous polarization. © 2010 Elsevier B.V. All rights reserved.

Mononuclear metal complexes of the type [ML1]Cl2 (where, M = = Cu(II), Co(II) or Ni(II) and L1 = ligand) were synthesized by the reaction of a new N4 coordinating ligand, N,N'-{(1,2-dimethylethanediylidene)bis[nitrilo( 2,1-ethanediyl)]}bis[benzamide] derived from the Schiff base of diacetyl with ethylenediamine and benzoic acid, and the corresponding hydrated metal chloride salts. The metal complexes were characterized by elemental analysis, melting point determination, molar conductance and magnetic moment measurements, IR, UV-Vis, 1H- and 13C-NMR, and ESR spectroscopy. The ligand and all the metal complexes were stable in the solid state at room temperature. From the analytical and spectroscopic investigations, the stoichiometry of the complexes was found to be 1:1 (metal:ligand). Based on the electronic spectra and magnetic moment data, the metal complexes had a square planar geometry. The molar conductance values show the 1:2 electrolytic nature of the metal complexes. A cyclic voltammetric study of the Cu(II) metal complex has also performed, which showed one electron quasi-reversible reduction around -0.92 to -1.10 V. In vitro biological activities of the ligand and metal complexes was checked against two bacteria Bacillus subtilis and Escherichia coli and two fungi Aspirgillus niger and A. flavus which showed the antibacterial and antifungal properties of the ligand and its metal complexes. 2012 Copyright (CC) SCS.

Singh G.,Insect Resistance Group | Sachdev B.,Insect Resistance Group | Sharma N.,Meerut College | Seth R.,University of Delhi | Bhatnagar R.K.,Insect Resistance Group
Applied and Environmental Microbiology | Year: 2010

Vegetative insecticidal protein (Vip3A) is synthesized as an extracellular insecticidal toxin by certain strains of Bacillus thuringiensis. Vip3A is active against several lepidopteran pests of crops. Polyphagous pest, Spodoptera frugiperda, and its cell line Sf21 are sensitive for lyses to Vip3A. Screening of cDNA library prepared from Sf21 cells through yeast two-hybrid system with Vip3A as bait identified ribosomal protein S2 as a toxicity-mediating interacting partner protein. The Vip3A-ribosomal-S2 protein interaction was validated by in vitro pulldown assays and by RNA interference-induced knockdown experiments. Knockdown of expression of S2 protein in Sf21 cells resulted in reduced toxicity of the Vip3A protein. These observations were further extended to adult fifth-instar larvae of Spodoptera litura. Knockdown of S2 expression by injecting corresponding double-stranded RNA resulted in reduced mortality of larvae to Vip3A toxin. Intracellular visualization of S2 protein and Vip3A through confocal microscopy revealed their interaction and localization in cytoplasm and surface of Sf21 cells. Copyright © 2010, American Society for Microbiology.

Devi S.,Meerut College | Srivastva M.,Meerut College
Indian Journal of Physics | Year: 2010

The solgel process has been successfully used to prepare silver/silica nanocomposites. After drying in air at 50°C for 30 mm, samples were heat treated in air, at 100, 200, 400 and 500°C for the formation of silver nanoparticles. Evolution of silver nano-particles in the amorphous Si0 2 matrix as a function of annealing temperature has been studied. Characterizations were made by X-ray diffraction, ultraviolet-visible, and infrared spectroscopy. Mechanisms of silver clusters formation in the densified silica matrix with respect to thermal treatment are discussed. © 2010 IACS.

Prakash D.,Meerut College | Saxena R.S.,Meerut College
Journal of Applied Pharmaceutical Science | Year: 2013

There is a dearth of information regarding to prevalence and antimicrobial susceptibility pattern of E. coli, a most common cause of nosocomial infections, in community and hospital acquired urinary tract infections. Theantibiotic resistant pattern against E. coli varies when isolated from different sources. This study was carried out with an objective to isolate E. coli from male and female patients infected with hospital and community acquired UTI. The isolates were subjected to five different antibiotic categories comprising 18 antibiotics. On the basis of antibiotic resistance profiling MAR index was calculated. Prevalence of UTI was found 69.17% which was high in hospital (56.63%) than community settings (43.37%). Females were found more susceptible to UTI than males in both settings. Prevalence of E. coli was found 61.45% among all isolates. Carbepenems showed highest sensitivity against E. coli isolated from UTI patients. The highest MAR indices were 0.8 (3.57%) and 0.7 (8.69%) of E. coli isolated in hospital and communitysettings. The present study suggests that females are highly susceptible toUTI in both community and hospital settings as well as the occurrence of E.coli were also found high in female patients. E. coli showed resistance against commonly prescribed antibiotics. © 2013 Devanand Prakash and R.S. Saxena.

N-substituted pyridine hydrazide (pyridine-2-carbonyl chloride and 4-chloro-benzoic acid hydrazide) undergoes hydrazide formation of the iminic carbon nitrogen double bond through its reaction with cobalt(II), nickel(II), and copper(II) metal salts in ethanol which are reported and characterized based on elemental analyses, IR, solid reflectance, magnetic moment, molar conductance, and thermal analysis (TG). From the elemental analyses data, 1: 2 metal complexes are formed having the general formulae [MCl 2(HL) 2] · yH 2O (where M = Co(II), Ni(II), and Cu(II), y = 13). The important infrared (IR) spectral bands corresponding to the active groups in the ligand and the solid complexes under investigation were studied. IR spectra show that ligand is coordinated to the metal ions in a neutral bidentate manner with ON donor sites. The solid complexes have been synthesized and studied by thermogravimetric analysis. All the metal chelates are found to be nonelectrolytes. From the magnetic and solid reflectance spectra, the complexes (cobalt(II), nickel(II), and copper(II)) have octahedral and square planner geometry, respectively. The antibacterial and antifungal activity's data show that the metal complexes have a promising biological activity comparable with the parent ligand against bacterial and fungal species. © 2012 Jagvir Singh and Prashant Singh.

A series of binuclear transition metal complexes of the type [M 2(L)2X4)]·nH2O (where, M = Cu(II), Ni(II), Co(II) or Zn(II), X= Cl-/ CH3COO- and L = ligand) of a Schiff base ligand derived from 1-amino-5-methyl-2,6-pyrimidine- dione and 2,3-butanedione have been synthesized and characterized by elemental analysis, molar conductance measurements, magnetic moment measurements, IR, UV-visible, 1H NMR, EPR and mass spectral studies. Electronic spectral data and magnetic moment values indicate octahedral geometry for all the metal complexes. In vitro antimicrobial activity of ligand and its metal complexes were also studied against bacteria (Bacillus subtilis and Escherichia coli) and fungi (Aspergillus niger and Aspergillus flavus) which show antimicrobial activity of ligand and binuclear metal complexes.

Newly hatched W.L.H. chicks were infected with Ascaridia galli eggs low dose (500 eggs) and subsequently treated with cadmium acetate (5mg/Kg body wt.). After 30 days of post infection and treatment spleen showed various pathological changes. With low dose of infection the capsular was ruptured at various places and white pulp showed inflammatory edema, presence of secondary nodules, separation of inner capsular wall with inflammatory and non inflammatory edema. Sinus venosus showed lymphoid hyperplasia.

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