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171.
The complex permittivity spectra for tert-butyl alcohol (TB) with 2-propanol (2P) were determined over the frequency range of 10 MHz to 20 GHz using the time domain reflectometry (TDR) in the temperature range 25 °C to 55 °C for 11 different concentrations of the system. The static dielectric constant (ε0) and relaxation time (τ) have been determined these spectra using the Debye model. Excess properties and Kirkwood correlation factor of the mixtures have been determined. The excess permittivity is found to be positive in the tert-butyl alcohol rich region and negative in the 2-propanol rich region. However, the excess inverse relaxation time has different trend. The static dielectric constants for the mixtures have also been fitted with the modified Bruggeman model by assuming an additional parameter in the model. It appears that structure of the TB–2P dimer in the TB rich region favors parallel dipole orientation, whereas in the 2P rich region, it favors antiparallel orientation. 相似文献
172.
Kantak JB Bagade AV Mahajan SA Pawar SP Shouche YS Prabhune AA 《Applied biochemistry and biotechnology》2011,164(7):969-978
A lipolytic mesophilic fungus which produces lipase extracellularly was isolated from soil. Based on ITS1-5.8S–ITS4 region
sequences of ribosomal RNA, it was concluded that the isolate JK-1 belongs to genus Rhizopus and clades with Rhizopus oryzae. The present paper reports the screening, isolation, identification, and optimization of fermentation conditions for the
production of lipase (EC 3.1.1.3). Culture conditions were optimized, and the highest lipase production was observed in basal
medium with corn steep liquor as nitrogen source and glucose as carbon source. Maximum lipase production was observed at 72 h,
which is about 870 U/ml. Optimization of fermentation conditions resulted in 16-fold enhancement in enzyme production. 相似文献
173.
174.
S.M. Pawar 《Journal of Physics and Chemistry of Solids》2006,67(11):2386-2391
CdSe thin films have been electrodeposited potentiostatically onto stainless-steel and fluorine-doped tin oxide-coated glass substrates from an aqueous acidic bath using cadmium acetate ((CH3COO)2Cd·2H2O) as a Cd ion source. Preparative parameters such as deposition potential, solution concentration, bath temperature, pH of the electrolytic bath and deposition time have been optimized by using photoelectrochemical (PEC) technique to obtain well adherent and uniform thin films. The electrodeposits were dark brown in colour. The films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical absorption techniques. XRD studies reveal that films are polycrystalline, with hexagonal crystal structure. SEM shows that the films are compact, with spherical grains. Optical absorption studies reveal that the material exhibits a direct optical transition having band gap energy ∼1.72 eV. PEC study shows that the films are photoactive. 相似文献
175.
Synthesis of pharmaceutically important 1,5-disubstituted-4-haloimidazoles starting from α-aminonitriles is described. Some 1D and 2D NMR spectral features of these imidazoles are discussed. 相似文献
176.
Arun K. Sarkar Sushama M. Pawar Khushi L. Matta 《Journal of carbohydrate chemistry》2013,32(2):269-278
ABSTRACT Synthesis of three tetrasaccharides, namely, 0-α-L-fucopyranosyl-(1→3)-0-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-(1→3)-0-(β-D-galactopyranosyl)-(1→4)-β-D-glucopyranose (7), 0-α-L-fucopyranosyl-(1→4)-0-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-(1→3)-0-(β-D-galactopyranosyl)-(1→4)-D-glucopyranose (9), and 0-α-L-fucopyransoyl-(1→3)-0-(2-acetamido-2-deoxy-β-D-glucopyransoyl)-(1→6)-0-(β-D-galactopyranosyl)-(1→4)-D-glucopyranose (15) has been described. Their structures have been established by 13C NMR spectroscopy. 相似文献
177.
In the present investigation, a green aqua-mediated protocol for the synthesis of novel 2-arylidene indanone derivatives from 1,2,6,7-tetrahydro-8H-indeno[5,4-b]furan-8-one was unveiled. The application of water in organic reactions as a solvent is one of the incredible tools of green chemistry as reactions can be carried out under benign conditions minimizing environmental hazard and chemical waste. A library of novel 2-arylidene indanone derivatives are synthesized in good to excellent yield by utilizing the green potential of water as a solvent. The structures of all novel 2-arylidene indanone derivatives reported herein are confirmed using Fourier-transform infrared spectroscopy (FTIR), 1H NMR, 13C NMR, 19F NMR, distortionless enhancement by polarization transfer (DEPT), and High Resolution Mass Spectrometry (HRMS) techniques. 相似文献
178.
Hydrotropes are regaining importance in the currently blossoming field of self-organizing molecular systems. Their hydrophile-lipophile balance being on the higher side, their water solubility is significantly more than that of traditional surfactants, and, yet, they provide a sequestered niche or microenvironment for the solubilizate. Hydrotropes start aggregating at a certain concentration known as minimum hydrotrope concentration (MHC). The MHC values fall in the molar range because of which hydrotropes applications are reducing. In this article, the effect of various additives such as alcohols, electrolytes, surfactants, amines, and organic compounds on the behavior of sodium salicylate (NaSal) was investigated using viscosity measurement. 相似文献
179.
The Ag/Tl2Ba2Ca2Cu3O10/CdSe heterostructure was fabricated at room temperature by soft electrochemical processing technique for the first time. The formation of the heterostructure with non-diffusive interfaces was confirmed by X-ray diffraction. The crystallite sizes determined for Tl-2223 and CdSe films were 33 nm and 25 nm, respectively. The Tl2Ba2Ca2Cu3O10 film electrodeposited onto Ag-substrate has shown the superconducting transition temperature Tc at 116.5 K and Jc = 2.1 × 103 A/cm2. These values were found to improve after the deposition of CdSe onto Ag/Tl-2223 films. The effect of red He-Ne laser irradiation on the superconducting properties of heterostructure are studied and discussed at length in this paper. 相似文献
180.
Highly transparent and conductive Boron doped zinc oxide (ZnO:B) thin films were deposited using chemical spray pyrolysis (CSP) technique on glass substrate. The effect of variation of boron doping concentration in reducing solution on film properties was investigated. Low angle X-ray analysis showed that the films were polycrystalline fitting well with a hexagonal wurtzite structure and have preferred orientation in [002] direction. The films with resistivity 2.54×10−3 Ω-cm and optical transmittance >90% were obtained at optimized boron doping concentration. The optical band gap of ZnO:B films was found ∼3.27 eV from the optical transmittance spectra for the as-deposited films. Due to their excellent optical and electrical properties, ZnO:B films are promising contender for their potential use as transparent window layer and electrodes in solar cells. 相似文献