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The crystal structure of 1-[3-(3,4-dimethoxyphenyl)-2-propenoyl]pyrrolidine (C15H19NO3) (I) has been determined by X-ray analysis. It crystallizes orthorhombic space group Pbca with a = 24.295(3), b = 15.086(3), c = 7.552(3)A, V = 2768(1)A3, Z = 8, Dcalc = 1.254 g/cm3, mu = (Mo K(alpha)) = 0.87 cm(-1). The title compound has analgesic activity of cycloaliphatic amine part. The molecule is deviated from planar configuration.  相似文献   
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The refractive index (n) and thermal coefficient of the refractive index (dn/dt) are measured at four wavelengths for the diethylamine and triethylamine. The measurements are carried out using the Bellingham+Stanley model 60/ED high-accuracy Abbe refractometer. The optical permittivity (ε) and its variation with temperature are calculated. Applying the Cauchy equation, the following refractive properties are obtained: the optical dispersion dn/dλ, the dielectric dispersion dε/dλ, the variation of -dn/dT, dε/dT, as a function of wavelength (λ), and Cauchy's constants against temperature. Additionally, molar refractivity versus temperature and wavelength are determined.  相似文献   
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Research on Chemical Intermediates - A lipase-immobilized dense sodium alginate membrane was prepared and used for the esterification of ethyl alcohol and lactic acid in a pervaporation reactor...  相似文献   
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The aim of this study depends on understanding the effect of target‐to‐substrate distance (DTS) on ZnO thin films deposited by r.f. magnetron sputtering on to glass substrates at room temperature conditions. The DTS was changed from 35 mm to 65 mm with steps of 5 mm at 165 W and 0.2 Pa. The deposition rate of the films were ranged from 76 Ǻ / min to 146 Ǻ / min, while 10‐3 Ω.cm was obtained as the resistivity value with the help of four point probe technique. The structural investigations were carried out by using both the x‐ray diffraction (XRD) and high resolution transmission electron microscopy. According to XRD observations, the films were (002) oriented. Surface behaviour of the ZnO films was examined with atomic force microscopy and scanning electron microscopy. The root mean square (RMS) values were varied from 4.6 nm to 22.8 nm. Also, optical properties were obtained from UV–visible spectrophotometer and the transmittances as around 80 %. At 45 mm DTS value, the minimum resistivity measured as 9 × 10− 4 Ω.cm with 76 Ǻ / min deposition rate. The RMS was obtained as 4.9 nm and transmission was measured as 85.30 %, while band gap was 3.45 eV.  相似文献   
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Sorption process by surface plasmon resonance (SPR) was studied by exposing polymeric film made from anthracene labeled poly(methyl methacrylate) (An-PMMA) chains to various concentrations of saturated chloroform vapor. It was observed that the reflectivity changes were fast and reversible. The changes in reflectivity implied the swelling behavior of polymeric film during adsorbtion and can be explained by capturing of chloroform molecules. When clean air is introduced into gas cell similar behavior is observed but this time in the opposite direction as a result of desorption. Fick's law for diffusion was used to quantify real time SPR data for the swelling and desorption processes. It was observed that diffusion coefficients (D(s)) for swelling obeyed the t(1/2) law and found to be correlated with the amount of chloroform content in the cell. Diffusion coefficients (D(d)) during desorption were also measured and found to be increased as the saturated chloroform vapor content is increased in the cell.  相似文献   
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A new, rapid, selective, cheap and simple RP-LC method has been developed and validated for the simultaneous determination of clobetasol propionate and calcipotriol mixtures in bulk drugs (raw materials) and in a novel-fixed dose emulgel formulation. Separation was carried out using a NovaPak C18 column with methanol:water (74:26 v/v) as mobile phase for isocratic elution at a flow rate of 1.0 mL min?1. The column temperature was set at 25 °C. Calibration curves were established ranging between 0.5 and 20 μg mL?1 and 0.5 and 10 μg mL?1 for clobetasol propionate and calcipotriol, respectively. Limit of detection and limit of quantification values of the method was found as 0.16 and 0.48 μg mL?1 for clobetasol propionate and 0.10 and 0.30 μg mL?1 for calcipotriol, respectively. The method was validated in accordance with ICH guidelines and obtained results proved that the proposed method was precise, accurate, selective and sensitive for the simultaneous analysis of clobetasol propionate and calcipotriol. The proposed method can be easily applied for the simultaneous determination of clobetasol propionate and calcipotriol in prepared emulgel formulations. The obtained validation results showed that the RP-LC method is suitable for routine quantification of clobetasol propionate and calcipotriol in emulgel formulations with high precision and accuracy.  相似文献   
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