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1.
J Mol Model ; 27(8): 223, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244854

RESUMO

The unreported brucinium benzilate (BBA) crystal and Hirshfeld surface analysis indicated the influence of intramolecular hydrogen bonding network on the crystal structure. Protonation occurs at the tertiary nitrogen as it is the most basic site. The protonated N-H+ proton was observed at 7.08 ppm and the benzilate carbon COO- at 178.41 ppm. Molecular electrostatic potential (MEP) studies showed the electron-rich and electron-deficient sites in the molecule for understanding BBA interaction with an enzyme. Frontier molecular orbital (FMO) studies indicated that BBA molecule is thermodynamically stable and the HOMO-LUMO energy gap was found to be 4.454 eV. The highest interaction has the energy (322.86 kcal/mol) between tertiary ammonium N(LP) and H+. Inhibition tests showed that brucinium benzilate inhibits Bacillus cereus and Salmonella typhimurium bacteria. ADMET properties indicated that BBA has drug characteristics in binding plasma protein.

2.
J Nanosci Nanotechnol ; 18(5): 3455-3465, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442852

RESUMO

The nanocrystalline strontium cobalt molybdate composites of Sr1-xCoxMoO4 (x = 0, 0.3, 0.5, 0.7, 1) were prepared by mixing various mole ratios (SrM-1, SrCM-2, SrCM-3, SrCM-4 and CoM-5) and investigated for their humidity sensing properties. The composites were characterized by thermal analysis (TG/DTA), X-ray powder diffraction (XRD), Fourier Transform-Infrared spectroscopy (FT-IR), Fourier Transform Raman (FT-Raman) spectroscopy, Scanning Electron Microscopy (SEM/EDAX), Transmission Electron Microscopy (TEM) and UV-Visible absorption spectroscopy. The composites were subjected to dc electrical conductivity based humidity sensing studies at room temperature. The resistance measurements as a function of relative humidity (RH) in the range of 5-98% were carried out and the sensitivity factor (Sf) were calculated. The SrM-1 is found to possess with the highest Sf of 33014 ± 660 and CoM-5 is found to possess a low Sf of 868 ± 43. The SrCM-2, SrCM-3 and SrCM-4 possessed the sensitivity factors (Sf) of 915 ± 45, 3713 ± 185 and 3390 ± 102 respectively.

3.
Artigo em Inglês | MEDLINE | ID: mdl-24878440

RESUMO

Piperazine-1,4-diium bis 2,4,6-trinitrophenolate is one of the useful organic materials with nonlinear optical (NLO) and pharmaceutical applications. The material was grown by slow evaporation solution growth method at room temperature. The crystal system and lattice parameters were identified by single crystal XRD analysis. The grown material crystallizes in monoclinic system with P21/n space group. The main functional groups NH2, NO2, CN, CC, and phenolic 'O' atom were identified using FTIR analysis. The protons and carbons of grown crystal with various chemical environments were studied by 1H and 13C NMR spectroscopy to confirm the molecular structure. The optical properties of the crystal were studied by UV-vis-NIR spectroscopy and the transmission 100% range starts from 532 nm onwards. The optical band gap was measured as 2.63 eV from the plot of (αhν)2 versus hν. The thermal stability was detected at 304.1°C using TG-DTA analysis. The dielectric studies of the sample were carried out at different temperatures in the frequency range from 50 Hz to 5 MHz to establish the dielectric nature of the crystal. Photoconductivity measurements were carried out on the grown crystal. The Second Harmonic Generation (SHG) of the crystal was tested to confirm the nonlinear optical property.


Assuntos
Nitrocompostos/química , Dinâmica não Linear , Fenômenos Ópticos , Piperazinas/química , Piperazinas/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalização , Cristalografia por Raios X , Análise Diferencial Térmica , Condutividade Elétrica , Conformação Molecular , Piperazina , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho , Temperatura
4.
J Nanosci Nanotechnol ; 11(9): 8190-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22097553

RESUMO

We have studied various metallorganic and organometallic compounds by simultaneous nonisothermal thermogravimetric and differential thermogravimetric analyses to confirm their volatility and thermal stability. The equilibrium vapor pressures of the metallorganic and organometallic compounds were determined by horizontal dual arm single furnace thermoanalyzer as transpiration apparatus. Antoine coefficients were calculated from the temperature dependence equilibrium vapor pressure data. The model-fitting solid-state kinetic analyses of Al(acac)3, (acac = acetylacetonato), Cr(CO)6, Fe(Cp)2, (Cp-cyclopentadienyl), Ga(acac)3, Mn(tmhd)3, and Y(tmhd)3 (tmhd = 2,2,6,6,-tetramethyl-3,5-heptanedionato) revealed that the processes follow diffusion controlled, contracting area and zero order model sublimation or evaporation kinetics. The activation energy for the sublimation/evaporation processes were calculated by model-free kinetic methods. Thin films of nickel and lanthanum-strontium-manganite (LSM) are grown on silicon substrate at 573 K using selected metallorganic complexes of Ni[(acac)2en], La(tmhd)3, Sr(tmhd)2 and Mn(tmhd)3 as precursors by plasma assisted liquid injection chemical vapor deposition (PA-LICVD). The deposited films were characterized by scanning electron microscopy and energy dispersive X-ray analysis for their composition and morphology.

5.
Talanta ; 75(1): 27-31, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18371842

RESUMO

Hydrazine is determined spectrophotometrically by forming the derivative 2,4-dinitrophenylhydrazine from 2,4-dinitrochlorobenzene. The formed dinitro derivative undergoes condensation reaction to form the hydrazone with p-dimethylaminobenzaldehyde (p-DAB). The resulting yellow colored product is stable in acidic medium and has a maximum absorption at 458 nm. The colour system obeys Beer's law in the range 0-7 microg of hydrazine in an overall volume of 25 mL. The molar absorptivity is calculated to be 8.1 x 10(4) L mol(-1)cm(-1) with a correlation coefficient of 0.998. The relative standard deviation is 1.7% (n=10) at 6 microg of hydrazine. Interferences due to foreign ions have been studied and the method has been applied for the determination of hydrazine in boiler feed water.

6.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): o206, 2008 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21581660

RESUMO

The title compound, C(13)H(17)NO(2), has an intra-molecular N-H⋯O hydrogen bond, forming a planar six-membered ring with a mean deviation of 0.015 (5) Šfrom the plane. This plane makes a dihedral angle of 7.19 (8)° with the adjacent phenyl ring. Through an inter-molecular O-H⋯O hydrogen bond, the mol-ecules with their 2(1) screw and b-translation equivalents form a helical chain running parallel to the b axis.

7.
J Hazard Mater ; 153(1-2): 767-74, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17976903

RESUMO

Strontium added NiAl(2)O(4) composites prepared by sol-gel technique was utilized for the detection of methanol vapors. X-ray diffraction, scanning electron microscopy (SEM), FT-IR spectroscopy and nitrogen adsorption/desorption isotherm at 77K was employed respectively to identify the structural phases, surface morphology, vibrational stretching frequencies and BET surface area of the composites. The composites were prepared with the molar ratios of Ni:Sr as (1.0:0.0, 0.8:0.2, 0.6:0.4, 0.4:0.6, 0.2:0.8, 0.0:1.0) keeping the aluminum molar ratio as constant for all the compositions and were labeled as NiSA1, NiSA2, NiSA3, NiSA4, NiSA5 and NiSA6, respectively. The samples sintered at 900 degrees C for 5 h were subjected to dc resistance measurements in the temperature range of 30-250 degrees C to study the methanol vapor detection characteristics. The results revealed that the sensitivity in detecting methanol vapor increased with increase in temperature up to 175 degrees C for the composites NiSA1 and NiSA6 while for the other composites up to 150 degrees C and thereafter decreased. The sensitivity increased with increase in methanol concentration from 100 to 5000 ppm at 150 degrees C. Among the different composites NiSA5 showed the best sensitivity to methanol detection at an operating temperature of 150 degrees C.


Assuntos
Poluentes Atmosféricos/análise , Compostos de Alumínio/química , Metanol/análise , Níquel/química , Estrôncio/química , Condutividade Elétrica , Microscopia Eletrônica de Varredura , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
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