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41.
42.
Experimental Techniques - This paper suggests a new optical system for measuring shock wave characteristic that is installed in a shock tube. This shock tube has an innovative pneumatic rapid...  相似文献   
43.
A facile and convenient protocol was developed for the synthesis of symmetrical and unsymmetrical 3,3-di(indolyl)indolin-2-ones in low reaction times (22–35 min) and high yields (85–95%) using KSF as an efficient recyclable heterogeneous catalyst.  相似文献   
44.
Several N‐acyl‐2‐benzoylaziridines were previously prepared conveniently and used in the preparation of 5‐benzoyl‐2,4‐diaryl oxazolines in the presence of NaI. In this work, synthesis of some trans‐4‐benzoyl‐2,5‐diaryl oxazolines by a regio‐controlled and stereo‐controlled reaction in the presence of Iron (III) nitrate at room temperature is reported. A plausible mechanism has been proposed for ring expansion of N‐acylaziridines to oxazolines.  相似文献   
45.
Ring expansion of keto-aziridines to the corresponding 2-aminothiazoles (54–67 %) using ammonium thiocyanate in the presence of RuCl3 under refluxing acetonitrile is described. A plausible mechanism for the synthesis of substituted 2-aminothiazoles has been proposed.  相似文献   
46.
Computational methods based on the solution of the lattice-Boltzmann equation have been demonstrated to be effective for modeling a variety of fluid flow systems including direct simulation of particles suspended in fluid. Applications to suspended particles, however, have been limited to cases where the gap width between solid particles is much larger than the size of the lattice unit. The present extension of the method removes this limitation and improves the accuracy of the results even when two solid surfaces are near contact. With this extension, the forces on two moving solid particles, suspended in a fluid and almost in contact with each other, are calculated. Results are compared with classical lubrication theory. The accuracy and robustness of this computational method are demonstrated with several test problems.  相似文献   
47.
Cadmium telluride crystals grown by the Travelling Heater Method (THM) technique have been implanted with hydrogen using protons from 2 keV to 3 MeV.Electrical measurements indicate drastic changes in the concentration of defects, especially in the 0.15–0.20 and 0.45–0.60 eV bands. However, the modification induced by hydrogen depends on the starting material, implantation and annealing conditions.Furthermore, resistivity and carrier lifetime are also strongly affected by this treatment.  相似文献   
48.
Equations of state based on the statistical associating fluid theory for potentials of variable range (SAFT-VR) and the perturbed chain statistical associating fluid theory (PC-SAFT) have been used to model the PVT behavior of ionic liquids and the solubility of H2S in six imidazolium-based ionic liquids. The studied systems included [bmim][PF6], [hmim][PF6], [bmim][BF4], [hmim][BF4], [bmim][NTF2] and [hmim][NTF2] at various temperatures and pressures.For pure components, parameters of the models have been obtained by fitting the models to experimental data on liquid densities; the average relative deviation between the calculated and experimental densities for ionic liquids is less than 2.42% in the PC-SAFT model and 5.44% in the SAFT-VR approach, the latter which incorporates the square-well potential for short-range interactions. In both models an additional term has been added to account for dipole-dipole interactions between solute molecules resulting from the permanent charges on the chain molecules of the solvents. The model parameters have also been correlated as functions of the molecular weight of the solvents. For binary mixtures of ionic liquids and H2S, the association interactions between H2S molecules and between the ionic liquids and H2S molecules have also been taken into account in both approaches, using binary interaction coefficients. The results show an average deviation of less than 5% in the calculation of the mole fraction of H2S in the ionic liquids. The effect of inclusion of the polar term has been studied for binary systems in both models.  相似文献   
49.
The self-assembly of a custom-synthesized pentavalent cationic lipid (MVL5) and glycerol monooleate (GMO) with small interfering RNA (siRNA) results in the formation of a double-gyroid bicontinuous inverted cubic phase with colocalized lipid/siRNA domains as shown by synchrotron X-ray scattering and fluorescence microscopy. The high charge density (due to MVL5) and positive Gaussian modulus of the GMO-containing membranes confer optimal electrostatic and elastic properties for endosomal escape, enabling efficient siRNA delivery and effective, specific gene silencing.  相似文献   
50.
One of the main tasks in exploitation of ore-body is to select a suitable mining method. In mining method selection (MMS) problems, a decision procedure has to choose the best exploitation method that satisfies the evaluation criteria. It is generally hard to find a mining method that meets all the criteria simultaneously, therefore a good compromise solution is preferred as the final selection. Furthermore, the MMS problem is an inherently uncertain activity. To deal with the uncertainty, this paper presents an hybrid decision support system based on the fuzzy multi attribute decision making, named the fuzzy mining method selection with interrelation criteria (FMMSIC). FMMSIC models the relative weights of criteria by combining the fuzzy analytic network process and fuzzy entropy, and discusses using these hybrid techniques to determine the overall weights. Subsequently, the technique for order preference by similarity to an ideal solution method was modified by various normalization norms according to the MMS problem condition. Finally, to illustrate how the FMMSIC is used for the MMS problems, an empirical study of a real case is conducted. It shows by means of an application that the FMMSIC is well suited as a decision support system for the MMS.  相似文献   
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