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101.
The room temperature-stabilized γ-phase ion conducting Bi2Co0.1V0.9O5.35 thin film was deposited by spray pyrolysis on stainless steel substrate. The intra-grain and grain interior charge transfer
was confirmed in these films with impedance spectroscopic measurements done from 1 Hz to 10 MHz in the temperature range 550 K
to 741 K. Impedance data further revealed non-Debye kind of relaxation dispersion in the film. The relaxation frequency ranges
from 10 to 100 Hz, which predicts long range jumping of the oxygen ions with chemical diffusivity. The Arrhenius plots for
relaxation frequency and grain boundary conductivity were found to have same activation energy revealing grain boundary dominant
conduction. The effect of polycrystallinity on relaxation dispersion is investigated for the first time on Bi2Co0.1V0.9O5.35 thin films using impedance formalism. 相似文献
102.
R. S. Bhosale S. R. Sarda R. P. Giram D. S. Raut S. P. Parwe S. S. Ardhapure R. P. Pawar 《Journal of the Iranian Chemical Society》2009,6(3):519-522
A smooth conversion of substituted 1-(2-hydroxy phenyl)-3-phenyl-1,3-propane diones to flavones has been done using n-butyl-3-methyl-imidazolium tetrafluoroborate ionic liquid. 相似文献
103.
Chandrakant D. Pawar Sadhana L. Chavan Umakant D. Pawar Dattatraya N. Pansare Santosh V. Deshmukh Devanand B. Shinde 《中国化学会会志》2019,66(3):257-264
A series of novel thiazol‐2‐yl substituted‐1‐sulfonamide derivatives were synthesized from anilines. This involved the coupling of sulfonyl chlorides with thiazol amine to obtain the final compounds 7a – 7j and 8a – 8j . All synthesized compounds were screened for anticancer activity against MCF‐7, HeLa, A‐549, and Du‐145 cancer cell lines by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay. Preliminary bioassay suggests that most of the compounds show anti‐proliferation to different degrees, with doxorubicin used as positive control. The synthesized compounds show IC50 values in the range 2.74–8.17 μM in the different cell lines. The compounds 7d , 7e , 8a , 8d , and 8e were active compared to doxorubicin. The compounds having butyl and pantyl chains were more active than their lower and higher carbon chains and also their ring counterparts. 相似文献
104.
We have investigated the pressure-induced phase transition of InX (X = P, As, Sb) from Zinc-Blende (ZB) to NaCl structure by using realistic interaction potential model involving the effect of temperature. This model consists of Coulomb interaction, three-body interaction and short-range overlap repulsive interaction upto the second nearest neighbor involving temperature. Phase-transition pressure is associated with a sudden collapse in volume, showing the incidence of first-order phase transition. The phase-transition pressure is associated with volume collapses, and the elastic constants obtained from the present model indicate good agreement with the available experimental and theoretical data. 相似文献
105.
Manish Shinde Amol Pawar Soumen Karmakar Tanay Seth Varsha Raut Sunit Rane Sudha Bhoraskar Dinesh Amalnerkar 《Journal of nanoparticle research》2009,11(8):2043-2047
Uncapped silver nanoparticles were synthesized by DC arc thermal plasma technique. The synthesized nanoparticles were structurally
cubic and showed wide particle size variation (between 20–150 nm). Thick film paste formulated from such uncapped silver nanoparticles
was screen-printed on alumina substrates and the resultant ‘green’ films were fired at different firing temperatures. The
films fired at 600 °C revealed better microstructure properties and also yielded the lowest value of sheet resistance in comparison
to those corresponding to conventional peak firing temperature of 850 °C. Our findings directly support the role of silver
nanoparticles in substantially depressing the operative peak firing temperature involved in traditional conductor thick films
technology. 相似文献
106.
Thin films of lead telluride (PbTe) of thicknesses ranging from 1000 Å to 2500 Å have been prepared by co‐evaporation (three temperature) technique, onto precleaned amorphous glass substrates at various temperatures. The deposited samples were annealed and annealed samples were used for characterization. Resistivity of these samples was measured by four‐probe technique as a function of thickness and temperature. Activation energy for charge transport have been evaluated and found in the range of 0.09 to 0.106 eV. Thermoelectric power has been measured and found to be positive indicating that the samples are p‐type semiconducting material. Mobility variation with temperature has been estimated (evaluated) and correlated with scattering mechanism in the entire range of temperature studied. The X‐ray diffraction analysis confirmed that films are polycrystalline having cubic structure cell and lattice parameters are reported. 相似文献
107.
108.
Stability‐indicating HPLC assay for lysine–proline–valine (KPV) in aqueous solutions and skin homogenates
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Kasturi R. Pawar Vanisree Mulabagal Forrest Smith Chandra S. Kolli Vijaya K. Rangari R. Jayachandra Babu 《Biomedical chromatography : BMC》2015,29(5):716-721
A simple, sensitive and stability‐indicating high‐performance liquid chromatographic (HPLC) assay method was developed and validated for a bioactive peptide, lysine–proline–valine (KPV) in aqueous solutions and skin homogenates. Chromatographic separation was achieved on a reversed phase Phenomenex C18 column (4.6 × 250 mm, packed with 5 µm silica particles) with a gradient mobile phase consisting of 0.1% trifluoroacetic acid (TFA) in water (A) and 0.1% TFA in acetonitrile (B). The proposed HPLC method was validated with respect to accuracy, precision, linearity, repeatability, limit of detection (LOD) and limit of quantitation (LOQ). The calibration curve was linear with a correlation coefficient (r) of 0.9999. Relative standard deviation values of accuracy and precision experiments were <2. The LOD and LOQ of KPV were 0.01 and 0.25 µg/mL, respectively. Under stress conditions (acid, alkali and hydrogen peroxide) KPV yielded lys–pro–diketopiperazine as major degradation product, which was identified by flow injection MS analysis. The developed HPLC method was found to be efficient in separating the active peptide from its degradation products generated under various stress conditions. Also, the validated method was able to separate KPV from other peaks arising from endogenous components of the skin homogenate. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
109.
A variety of ortho-hydroxy substituted aromatic carbonyl compounds were regioselectively iodinated with iodine and iodic acid in excellent yields. 相似文献
110.
V. B. Sagar M. S. Oak S. M. Pawar C. K. Sivaramakrishnan S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1990,139(1):121-126
A method for the recovery and purification of233U from phosphate containing analytical waste is developed. Extraction studies with DBDECMP (Di-butyl, N, N-diethylcarbamoyl-methyl phosphonate) in xylene were carried out to explore the feasibility of separation and purification of233U from such wastes. Based on the data obtained, optimum conditions for the recovery of233U are suggested. 相似文献