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51.
In recent years, angular and linear phenoxazines and their derivatives and polymers have attracted much attention due to their great pharmacological and industrial utility. So it becomes imperative to review the work done in this area more frequently. Therefore, various synthetic routes for phenoxazines are reviewed here comprehensively.  相似文献   
52.
The entropy of fusion of linear vinyl polymers [polypropylene, polystyrene, and poly(vinyl chloride)] having asymmetric carbon atoms was calculated on the basis of the rotational isomeric state model. The results are found to be in good agreement with the experimental entropies of fusion per bond for these polymers.  相似文献   
53.
In this paper we present a comparative study of inelastic interactions of C12-Em and p-Em at 4·5 GeV/c per nucleon. The multiplicity distributions and their correlations have been studied. The results show a strong correlation of n s onn h in the case of C12-Em but not in the case of p-Em. It is also shown that the n s increases with the increase of the projectile mass. The angular distribution of the target fragments in C12-Em shows a massive forward collimation. Comparison is also made in the pseudorapidity distribution of both C12-Em and p-Em, the result shows many interesting features.  相似文献   
54.
A simple and straightforward approach was developed to construct 5H‐benzo[b]carbazole derivatives by iron catalysis in a cascade sequence. The notable features of this work include an atom‐economical cascade sequence, unprecedented 1,4‐sulfonyl migration, tolerance of a variety of functional groups, good yields, and an economical catalytic system.  相似文献   
55.
Porous aerogels of CdS that exhibit quantum confined optical properties have been prepared by supercritical drying of wet CdS gels prepared by oxidative stripping of nanoparticle capping groups. The water-to-surfactant ratio (W) employed in the preparation of the nanoparticles is found to have a large impact on the surface areas of resultant aerogels, with W=5 samples producing mesoporous samples with the highest surface areas and cumulative pore volumes. In contrast, the concentration of the CdS sol employed in the gelation has only a small effect on the porosity characteristics, but a large impact on the apparent crystallite and chromophore sizes in as-prepared aerogels. Higher concentrations of the sol result in larger crystallite sizes and lower degrees of quantum confinement, as evidenced by a red shift in the absorbance spectra.  相似文献   
56.
The synthesis and cation binding properties of chiral crown ethers derived from 7-deoxycholic acid along with their application in asymmetric Michael reaction are described.  相似文献   
57.
In this work, DFT calculations for the designed eutectic mixtures (EMs) using oxoazolidine 2,4-dione (OZD) and zinc chloride (ZnCl2) are done. The interaction between the hydrogen bond donor and hydrogen bond acceptor at atomic level to get EMs are studied using DFT calculations. At room temperature, the stability of these various systems have been investigated using thermodynamic values or parameters such as enthalpy, free energy and others. DFT calculations is used to investigate the possibility of forming the systems (EMs). Further, the impact of varying the temperature on each system was also investigated (323K, 348K). Various other thermodynamic parameters are studied like dipole moment, hardness, chemical potential of the systems (individual molecules and EMs) at different temperatures. The results of the calculations showed that O1Z4 and O4Z1 have maximum dipole moment having values 8.1291, 9.8801 respectively, indicating maximum polarizability. Change in free energy for O1Z4 is least and was found to be ?37.2496 kcal/ mol. Further on changing the temperature, the parameters do not show much variation. Additionally, we have analyzed structure activity relationship (SAR) method to understand the physico-chemical properties of designed EMs and predict their regression and correlation to optimized energy. From the calculated values of pOE model, the value of r2 is 0.9995 confirms the validity of the equation obtained. The results of this study suggest a link between the structures that have been utilized to describe the intermolecular interaction between the hydrogen bond donor and acceptor, as well as the stability of the EMs.  相似文献   
58.
59.
The free energy of a quark-gluon plasma fireball in the hadronic medium is calculated in the Ramanathan et al statistical model after incorporating the effect of curvature. The result with the inclusion of curvature is found to produce significant improvements in all the parameters we calculated with respect to the earlier results. The surface tension with this curvature effect is found to be 0.17T c3, which is two times the earlier value of surface tension which is 0.078T c3, and this new result is nearly close to the lattice value 0.24T c3. As far as transition is concerned, a thermodynamic variable like entropy shows weakly first-order phase transition and it shows continuity in the behaviour of specific heat.  相似文献   
60.
Nickel-doped anatase TiO2 nanoparticles have been prepared by sol-gel method. The X-ray powder diffraction study reveals that all the prepared samples have pure anatase phase tetragonal system. The average crystallite size of the prepared sample is 14 nm, when found through transmission electron microscope. A strong frequency dependence of both dielectric constant (?′) and dielectric loss (tan δ) were observed for various dopant levels at room temperature in the frequency range of 42 Hz to 5 MHz. At low frequency, the piling up of mobile charge carriers at the grain boundary produces interfacial polarization giving rise to high dielectric constant. The asymmetric shape of frequency dependence of the dielectric loss for the primary relaxation process is observed for each concentration. From the ac conductivity studies, the reduction in conductivity may arise due to the decreasing particle with the increase in Ni-dopant level.  相似文献   
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