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101.
The yrast spectra, intrinsic quadrupole moments and root mean square radii for each angular momentum state, calculated for 108–112Ru isotopes by carrying out Cranked-Hartree-Fock-Bogoliubov (CHFB) calculations. These calculations have been performed by employing pairing-plus-quadrupole-quadrupole effective interaction operating in a reasonably large valence space outside 76Sr core. The experimentally available spectra upto 10+ is reasonably well reproduced. Our results indicate that there is a possibility for observing backbending phenomenon in 108,110,112ru at spins 12 +, 20+ and 14+, respectively, which remains yet to be confirmed experimentally.  相似文献   
102.
Two new prenylated isoflavanones have been isolated from the roots of Glycyrrhiza glabra L. along with the known compounds cetoleic acid, β-sitosterol, stigmasterol, lanast-5,24-dien-3β-D-glucuronopyranoside, and glucuronic acid. The structures of the prenylated isoflavanones have been established as 8-isoprenyl-7,4′-dihydroxylicoisoflavanone (glabraisoflavanone A) and 7,3′-dihydroxy-8-isoprenyl-4′-cyclogeranioloxyisoflavanone (glabraisoflavanone B) on the basis of spectral data analyses and chemical reactions.  相似文献   
103.
Amino acids have been used as catalysts for the study of kinetic of enolisation of m-Methylacetophenone, in which iodination has been the chosen method. Several parameters like effect of ketone concentration, effect of dielectric constant, effect of catalysts etc. have been investigated for their effect on enolisation kinetics. The study is focused on β-alanine, dl-alanine, l-alanine and Glycine for their effects on the rate. The order of the rate constants obtained has been found to be in the order of increasing dipole moments of the amino acids i.e. l-alanine < Glycine < dl-alanine < β-alanine. With an increase in the temperature from 323 K to 338 K, an increase in the rate was from 1.3 to 2.12 mol?1 min?1. The ongoing reaction was found to be bimolecular in nature. The values of different thermodynamic parameters like Entropy (ΔS), Enthalpy (ΔH), Energy of activation (ΔEa) and Gibbs free energy (ΔF) were found to be 6.20 e.u., 24.74 cal mol?1, 25.20 k cal mol?1 and 24.54 cal mol?1 respectively.  相似文献   
104.
A constitutive model that highlights a special viscoelastic property of materials with cellular microstructures is developed. We model the microstructure as a regularly arranged system of the same elastic cells that are mutually interconnected by elastic linkages. The space between cells is filled by a fluid that may flow freely within this extracellular space. The macroscopic behavior of the whole structure is studied by means of continuum mechanics using a differential scheme with internal variables. Here, the internal variables are chosen as the distances that separate neighboring cells. The evolution equations are derived from the Clausius–Planck inequality, which considers the internal dissipation to be exclusively due to the extracellular fluid movement. Special attention is paid to incompressible materials in the context of uniaxial load. In this context, the importance of the fluid viscosity on material behavior is related to microstructural parameters like the cells’ dimensions and the relative stiffness between the cells and matrix elastic reinforcement.  相似文献   
105.
A set of C,N-chelated organotin(IV) ferrocenecarboxylates, [LCN(n-Bu)Sn(O2CFc)2] (1), [(LCN)2Sn(O2CFc)2] (2), [LCN(n-Bu)Sn(O2CCH2Fc)2] (3), [LCN(n-Bu)Sn(O2CCH2CH2Fc)2] (4), [LCN(n-Bu)Sn(O2CCHCHFc)2] (5), [LCN(n-Bu)Sn(O2CfcPPh2)2] (6), [(LCN)2Sn(O2CfcPPh2)2] (7), and [LCN(n-Bu)2Sn(O2CFc)] (8) (LCN = 2-(N,N-dimethylaminomethyl)phenyl, Fc = ferrocenyl and fc = ferrocene-1,1′-diyl) has been synthesized by metathesis of the respective organotin(IV) halides and carboxylate potassium salts and characterized by multinuclear NMR and IR spectroscopy. The spectral data indicated that the tin atoms in diorganotin(IV) dicarboxylates bearing one C,N-chelating ligand (1 and 3-6) are seven-coordinated with a distorted pentagonal bipyramidal environment around the tin constituted by the n-butyl group, the chelating LCN ligand and bidentate carboxylate. Compounds 2 and 7 possessing two chelating LCN ligands comprise octahedrally coordinated tin atoms and monodentate carboxylate donors, whereas compound 8 assumes a distorted trigonal bipyramidal geometry around tin with the carboxylate binding in unidentate fashion. The solid state structures determined for 1⋅C6D6 and 2 by single-crystal X-ray diffraction analysis are in agreement with spectroscopic data. Compounds 1, 3-5, and 8 were further studied by electrochemical methods. Whereas the oxidations of ferrocene units in bis(carboxylate) 2 and monocarboxylate 8 proceed in single steps, compound 1 undergoes two closely spaced one-electron redox waves due to two independently oxidized ferrocenyl groups. The spaced analogues of 2, compounds 3-5, again display only single waves corresponding to two-electron exchanged.  相似文献   
106.
Before commencing any nanotoxicological study, it is imperative to know the state of the nanoparticles to be used and in particular their size and size distribution in the appropriate test media is particularly important. Particles satisfying standards can be commercially purchased; however, these invariably cannot be used directly and need to be dispersed into the relevant biological media. Often such changes in the environment or ionic strength, or a change in the particle concentration, results in some aggregation or a shift in the particle size distribution. Such unexpected aggregation, dissolution or plating out, if unaccounted for, can have a significant effect on the available nanoparticle dose and on interpretation of any results obtained thereafter. Here, we demonstrate the application of characterisation instrumentation that sizes nanoparticles based on their Brownian motion in suspension. Unlike classical light-scattering techniques, the nanoparticle tracking and analysis (NTA) technique allows nanoparticles to be sized in suspension on a particle-by-particle basis allowing higher resolution and therefore better understanding of aggregation than ensemble methods (such as dynamic light scattering (DLS) and differential centrifugation sedimentation (DCS)). Results will be presented from gold (standard) nanoparticles in biologically relevant media that emphasise the importance of characterisation of the nanoparticle dispersion. It will be shown how the NTA technique can be extended to multi-parameter analysis, allowing for characterization of particle size and light scattering intensity on an individual basis. This multi-parameter measurement capability allows sub-populations of nanoparticles with varying characteristics to be resolved in a complex mixture. Changes in one or more of such properties can be followed both in real time and in situ.  相似文献   
107.
Results of detailed structural, dielectric, magnetic and magnetoelectric studies of (x)PbZr0.52Ti0.48O3-(1−x)Mn0.3Co0.6Zn0.4Fe1.7O4 composites where x=65, 70, 75 and 80 are shown in this work. Manganese substituted cobalt ferrites are known to exhibit large strain derivative (dx/dH) and on the other hand substitution of Zn in pure cobalt ferrite is known to enhance its permeability μ and permittivity ε. The choice of ferrite as Mn, Zn simultaneously substituted cobalt ferrite (MCZFO) is made keeping in view that for good magnetoelectric (ME) voltage coefficient the magnetostrictive constituent phase of the composite should have large strain derivative (dx/dH) along with large permittivity and permeability. It is shown here that although the dielectric transition temperature changes significantly with change in the mole ratio of the two component phases, magnetic transition temperature (much less compared to the bulk cobalt ferrite) is relatively non-responsive to the changing molar ratio of the two component phases. In the vicinity of the magnetic transition temperature we observed an anomaly in tan δ vs. T plots, which indicates a possible magnetoelectric coupling in the samples. Magnetoelectric voltage coefficient (αE) has been measured using static magnetoelectric method. Highest magnetoelectric voltage coefficient (αE=0.312 mV/cmOe) is obtained for sample 80:20 at HDC=1000 Oe.  相似文献   
108.
We have studied the electronic structure, magnetic and transport properties of some Co based full Heusler alloys, namely Co2TiZ (Z=Si, Ge and Sn), in the frame work of first-principle calculations. The calculations show that Co2TiZ (X=Si, Ge and Sn) are to be half-metallic compounds with a magnetic moment of 2 μB, well consistent with the Slater-Pauling rule. The electronic structure results reveal that Co2TiZ has the high density of states at the Fermi energy in the majority-spin state and show 100% spin polarization. Our results also suggest that both the electronic and magnetic properties in these compounds are intrinsically related to the appearance of the minority-spin gap. The origin of energy gap in the minority-spin states is discussed in terms of the electron splitting of Z (Z=Si, Ge and Sn) and 3d Co atoms and also the d-d hybridization between the Co and Ti atoms. The transport properties of these materials are discussed on the basis of Seebeck coefficients, electrical conductivity coefficients and thermal conductivity coefficients.  相似文献   
109.
Oral cancer is a major cause of mortality in South Asian men owing to rampant tobacco abuse. Cancers are also reported in non‐tobacco habitués, especially women, attributed to chronic irritations from irregular/sharp teeth, improper fillings, and poorly fit dentures. Conventional screening approaches are shown to be effective for high‐risk groups (tobacco/alcohol habitués). Raman spectroscopy (RS) is being extensively explored as an alternate/adjunct tool for diagnosis and management of oral cancers. In a previous Raman study on sequential oral carcinogenesis using hamster buccal pouch model, misclassifications between spectra from control and carcinogen [7,12‐dimethylbenz(a)anthracene (DMBA)]‐treated tissues were observed. Histopathology of some control tissues suggested pathological changes, attributable to repeated forceps‐induced irritations/trauma during animal handling. To explore these changes, in the present study, we recorded spectra from three different types of controls – vehicle control (n = 45), vehicle contralateral (n = 45), and DMBA contralateral (n = 70) – exposed to varying degree of forceps handling, along with DMBA‐treated pouches (n = 70) using a 14‐week carcinogenesis protocol. Spectra certified on the basis of histopathology and abnormal cell proliferation (cyclin D1 expression) were used to build models that were evaluated by independent test spectra from an exclusive set of DMBA‐treated and control animals. Many DMBA‐contralateral, vehicle‐control, and vehicle‐contralateral spectra were identified as higher pathologies, which subsequently corroborated with histopathology/cyclin D1 expression. Repeated forceps‐mediated injuries/irritations, during painting and animal handling, may elicit inflammatory responses, leading to neoplasm. The findings of the study suggest that RS could identify micro‐changes. Further, RS‐based in vivo imaging can serve as a promising label‐free tool for screening even in the non‐habitué population where conventional screening is shown to be not effective. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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