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1.
A capillary GC method employing an internal standard has been developed and successfully used for quantitative determination both of the raw materials used for the manufacture of m-phenoxybenzaldehyde and for the components of the reaction mixtures obtained at various stages of the development of the process. A complete analysis can be performed in a single temperature programmed run.  相似文献   
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Abstract— The weak and reversible binding of the antifungal drug, griseofulvin (GF), to calf thymus DNA has been demonstrated by difference spectroscopy and the quenching of the fluorescence of GF by DNA observed. The value of K n was determined to be 800 M -1by fluorescence quenching titration. Adenosine and guanosine also exhibit difference spectra with GF and quench GF fluorescence indicating that they may be the site of both binding and energy transfer. The in vitro photosensitization of DNA by griseofulvin is shown to occur. It is proposed that the clinically observed in vivo photosensitizing action of griseofulvin may result from binding followed by excitation energy transfer and that this may also be important in the antifungal activity of the drug.  相似文献   
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This paper investigates the rotating flow and heat transfer of a viscous fluid induced by a stretching surface. The nonlinear problem subject to a given skin friction at the boundary is solved. Analytic solution is obtained using homotopy analysis method. The velocity, temperature, and stretching velocity is calculated for different values of the rotation parameter (λ). The obtained results are compared with the well known results of rotating flow induced by a stretching surface by using four sets of boundary conditions. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Muhammad Sajid 《Ionics》2018,24(1):19-32
Bentonites are promising materials for electrochemical sensing because of their unique physicochemical properties. They have relatively high surface area, good adsorption and ion-exchange ability, highly tunable surface and interlayer composition, non-toxic nature, and excellent biocompatibility. Moreover, they are outstanding substrates for stable immobilization of different functional moieties. The primary focus of this review article is to highlight the applications of bentonite-modified electrodes for the analysis of organic and inorganic analytes in different matrices. A brief summary on the necessity of analysis of different compounds is provided. For the first time, features and applications of bentonite-modified electrodes are critically appraised. The key features of bentonite-modified electrodes that enhance their electrocatalytic activity toward detection of certain target analytes are highlighted. At the end, an account of current status of bentonite-modified electrodes along with future research directions is provided.  相似文献   
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Two new heteroleptic palladium(II) complexes have been synthesized by reacting equimolar quantities of palladium(II) chloride, sodium 4‐(2‐methoxyphenyl)piperazine‐1‐carbodithioate and diphenyl‐p‐tolylphosphine ( 1 ) or tri‐p‐tolylphosphine ( 2 ). Complexes 1 and 2 have been characterized using elemental analysis, Fourier transform infrared spectroscopy, multinuclear NMR (1H, 13C and 31P) spectroscopy and single‐crystal X‐ray analysis. The latter technique confirms a pseudo square‐planar geometry in which two adjacent positions are occupied by bidentate dithiocarbamate while chloro and substituted triphenylphosphine are present at the remaining two positions. The anticancer activity of both complexes against five different cancer cell lines (LU – human lung carcinoma, established at UIC, Department of Surgical Oncology; MCF7 – human breast adenocarcinoma, ATCC number HTB‐22?; MDA‐MB‐231 – human breast adenocarcinoma, ATCC number HTB‐26?; Hepa‐1c1c7 – mouse liver hepatoma, ATCC number CRL‐2026?; PC‐3 – human prostate adenocarcinoma, ATCC number CRL‐1435?) was determined by MTT assay, revealing 2 has higher activity than 1 . A drug–calf thymus DNA binding study with UV–visible spectroscopy reveals a higher DNA binding affinity of 2 (3.511 × 104 M?1) than 1 (4.213 × 103 M?1). Density functional theory studies confirm the relatively more stable nature of 2 than 1 . Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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The present paper contains the exact solutions for thin film flows of a micropolar fluid. Thin films are considered for three different geometries namely: (i) flow down an inclined plane, (ii) flow on a moving belt and (iii) flow down a vertical cylinder. The exact solution is obtained for the velocity and micro-rotation in first two cases for both weak and strong concentrations of the microelements. However, the exact expression for the micro-rotation is obtained for the third case and a numerical solution is presented for the velocity. The micro-rotation and velocity fields are sketched and discussed for different values of the material parameters. It is observed that the rotation of the microelements at the boundary increases the velocity when compared with the case when there is no rotation at the boundary.  相似文献   
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The high specific capacitance along with good cycling stability are crucial for practical applications of supercapacitors,which always demands high-performance and stable electrode materials.In this work,we report a series of ternary composites of CoO-ZnO with different fractions of reduced graphene oxide(rGO) synthesized by in-situ growth on nickel foam,named as CZG-1,2 and 3,respectively.This sort of binder-free electrodes presents excellent electrochemical properties as well as large capacitance due to their low electrical resistance and high oxygen vacancies.Particularly,the sample of CZG-2(CoO-ZnO/rGO 20 mg) in a nanoreticular structure shows the best electrochemical performance with a maximum specific capacitance of 1951.8 F/g(216.9 mAh/g) at a current intensity of 1 A/g.The CZG-2-based hybrid supercapacitor delivers a high energy density up to 45.9 Wh/kg at a high power density of 800 W/kg,and kept the capacitance retention of 90.1% over 5000 charge-discharge cycles.  相似文献   
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Research on Chemical Intermediates - We prepared unique BiVO4/reduce graphene oxide (BiVO4/rGO) nanocomposite with enhanced photocatalytic ability by hydrothermal method applying...  相似文献   
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