نتایج جستجو برای: solvent effect quantum mechanic dielectric constant thermodynamic values
تعداد نتایج: 2575720 فیلتر نتایج به سال:
The density, viscosity, static dielectric constant and microwave dielectric loss of aqueous solutions of triglycine and tetraglycine have been studied at various temperatures from 0 to 60 °C. A very similar electrostrictive effect is observed for triglycine and tetraglycine solutions, indicating a different conformational behaviour of the two peptides in solution. The density b-coefficients dec...
در این تحقیق حلالها به دو دسته قطبی و غیرقطبی دسته بندی می شوند حلالهای سیکلوهگزان و تتراکلریدکربن غیرقطبی و حلالهای کلروفرم، استون و دی متیل سولفوکسید قطبی هستند. محاسبات نشان می دهند با کاهش ضریب دی الکتریک حلال تغییر انرژی آزاد گیبس فرایند تبدیل کنفورمر استوایی به محوری سیکلوهگزاتیون کاهش می یابد به عبارتی تمایل به محوری شدن با کاهش ضریب دی الکتریک افزایش می یابد. در واقع کنفورمر محوری ممان ...
Present work describes the formation of α-Fe2O3@SiO2 core shell structure by systematic layer by layer deposition of silica shell on core iron oxide nanoparticles prepared via various solvents. Sol-gel method has been used to synthesize magnetic core and the dielectric shell. The average crystallite size of iron oxide nanoparticles was calculated ∼20 nm by X-ray diffraction pattern. Morphologic...
We present a microfield approach for studying the dependence of the orientational polarization of the water in aqueous electrolyte solutions upon the salt concentration and temperature. The model takes into account the orientation of the solvent dipoles due to the electric field created by ions, and the effect of thermal fluctuations. The model predicts a dielectric functional dependence of the...
Solid coconut waste was produced after coconut milk extraction process and may still contain up to 24 wt.% oil content. In this work, extraction of oil from coconut waste using batch and soxhlet extractor was studied. Effect of particle size diameter, type of solvent and solvent to solid ratio on the kinetic and thermodynamic parameters; entropy, enthalpy and free energy of extraction were inve...
Electrostatic interactions play an important role in numerous self-assembly phenomena, including colloidal aggregation. Although colloids typically have a dielectric constant that differs from the surrounding solvent, the effective interactions that arise from inhomogeneous polarization charge distributions are generally neglected in theoretical and computational studies. We introduce an effici...
Dielectric relaxation measurements on Methanol – Dimethylaminoethanol solvent mixtures have been carried out across the entire concentration range using Time Domain Reflectometry technique at 15, 25, 35 and 45C over the frequency range from 10 MHz to 20 GHz. The mixtures exhibit a principle dispersion of the Davidson-Cole relaxation type at microwave frequencies. The Bilinear calibration method...
Microwave-assisted liquefaction has shown potential for rapid thermal processing of lignocellulosic biomass. The efficiency of microwave heating depends largely on the dielectric properties of the materials being heated. The objective of this study was to investigate the dynamic interactions between microwave energy and the reaction system during the liquefaction of a woody biomass sample. The ...
In response to charge separation or transfer, polar liquids respond in a simple linear fashion. A similar linear response for proteins might be expected from the central limit theorem and is postulated in widely used theories of protein electrostatics, including the Marcus electron transfer theory and dielectric continuum theories. Although these theories are supported by a variety of experimen...
Dielectric constants have been determined for dimethylsiloxane chains (CH3)3Si[OSi(CHJ210Si(CH3)3 in the thermodynamically good solvent cyclohexane and in the undiluted state, for degrees of polymerization x + 1 ranging from lQ2 to 1/nm 2 (where <,...2> is the mean-...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید