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101.
Lal Sohan Arora Sanjiv Kumar Vinod Rani Shikha Jagdeva Geetanjali 《Journal of Thermal Analysis and Calorimetry》2021,143(4):3267-3274
Journal of Thermal Analysis and Calorimetry - The different concentrations of chitosan were applied on cotton fabrics using glutaraldehyde as a cross-linking agent. The fabric samples were... 相似文献
102.
Saravanan M. Dhivakar S. Mohapatra M. Kutti Rani S. Vijayakumaran K. 《Journal of fluorescence》2022,32(4):1557-1563
The present work describes the synthesis and characterization of pyrene derivatives, N-(1-Pyrenoylmethyl) pyridinium bromide (PM-PB) and N-(1-Pyrenoylmethyl)-N,N,N-triethylammonium bromide (PM-TAB). The photophysical behavior of these molecules has been studied in various protic and aprotic solvents. Using steady state fluorescence intensity, fluorescence anisotropy and dynamic fluorescence lifetime studies, the sensitivity of these molecules towards the micellization process of bile salts has been monitored. These derivatives have been effectively used in estimating critical micellar concentration (CMC) of bile salt, sodium deoxycholate (NaDC).
相似文献103.
The γ- and conversion electron spectra following131Ba ε-decay are investigated, using HPGe detector and mini-orange electron spectrometer. Attention is particularly focussed
on identifying weak transitions associated with low energy high spin levels in131Cs level scheme earlier inferred in reaction studies but not yet observed in131Ba decay. Our experiment identifies 15 new gammas and 6 new conversion lines in this decay. Internal conversion coefficients
and multipolarities of several transitions are determined. Five new levels (3 with Iπ = 7/2+ and one each with Iπ 9/2+ and 11/2−) are introduced in the131Cs level scheme based on our observations taken together with the results from reaction studies. Spin-parity assignments to
a few other levels are also suggested 相似文献
104.
105.
Sol-Gel Synthesis of Nanocrystalline PZT Using a Novel System 总被引:2,自引:0,他引:2
Jacob K. Stanly Panicker N. Rani Selvam I. Packia Kumar V. 《Journal of Sol-Gel Science and Technology》2003,28(3):289-295
A simple system has been developed for the preparation of lead zirconate titanate, Pb(Zr
x
Ti1 – x
)O3 powders by sol-gel process. To achieve stable and homogeneous precursor solutions, chelating ligands such as acetic acid and acetylacetone have been used for the chemical modification of titanium and zirconium starting precursors. Phase-pure PZT powders were obtained, through a pyrochlore-free pathway, from the amorphous xerogel after heat treatment at 600°C. The formation of the crystalline phase, compositional homogeneity, sinterability, dielectric and piezoelectric characteristics of PZT are reported. 相似文献
106.
V. Srinivasa Rao M. Srinivasa Reddy K. Thomas S. S. Raju B. L. Rani B. Hari Babu 《Journal of solution chemistry》2018,47(3):430-448
The density (ρ), speed of sound (u) and refractive index (nD) of [Bmim][PF6], 2-pyrrolidone and their binary mixtures were measured over the whole composition range as a function of temperature between (303.15 and 323.15)?K at atmospheric pressure. Experimental values were used to calculate the excess molar volumes \( \left( {V_{m}^{\text{E}} } \right) \), excess partial molar volumes \( \left( {\overline{V}_{m}^{\text{E}} } \right) \), partial molar volumes at infinite dilution \( \left( {\overline{V}_{m}^{{{\text{E}},\infty }} } \right) \), excess values of isentropic compressibility \( \left( {\kappa_{S}^{\text{E}} } \right) \), free length \( \left( {L_{\text{f}}^{\text{E}} } \right) \) and speeds of sound \( \left( {u^{\text{E}} } \right) \) for the binary mixtures. The calculated properties are discussed in terms of molecular interactions between the components of the mixtures. The results reveal that interactions between unlike molecules take place, particularly through intermolecular hydrogen bond formation between the C2–H of [Bmim][PF6] and the carbonyl group of pyrrolidin-2-one. An excellent correlation between thermodynamic and IR spectroscopic measurements was observed. The observations were further supported by the Prigogine–Flory–Patterson (PFP) theory of excess molar volume. 相似文献
107.
Sundaravel Vivek Kumar Mani Anusha Rani Abdulrahman I. Almansour Raju Suresh Kumar S. Athimoolam Raju Ranjith Kumar 《Tetrahedron》2018,74(35):4569-4577
A facile syntheses of novel poly-substituted pyridine/benzo fused cyclododecane hybrid heterocycles have been achieved through one-pot multi-component tandem strategy employing cyclododecanone, aromatic aldehydes and malononitrile. 相似文献
108.
109.
110.
This article reports an attempt on the studies on resistance of oxidative stress by the prodrug, simvastatin (SV). Cetyltrimethylammonium dichromate has been used as a lipid compatible oxidant to study the oxidation kinetics of SV in organic media. The reaction undergoes via an ionic mechanism without any side product. The reaction is found to be acid catalyzed and sensitive to solvent polarity. The increase in the rate constant due to an increase in hydrophobicity (apolarity) of the solvent indicates the existence of a less polar transition state. Furthermore, the decrease in the rate constant due to an increase in [CTAB] suggests partitioning of the substrates and the oxidants into two different domains with different polar characteristics akin to a reversed micellar aggregates. Considering the above results and the thermodynamic parameters, a reaction mechanism has been proposed, wherein a complex formed at the interface of the two domains due to the reactant and the oxidant in a fast process decomposes to the products in a slow process in the nonpolar bulk. 相似文献