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991.
Paul Chekhonin Jan Engelmann Carl‐Georg Oertel Bernhard Holzapfel Werner Skrotzki 《Crystal Research and Technology》2014,49(6):435-439
In the present study the relative angular resolution of an electron backscatter diffraction system based on Hough transform analysis has been determined with a silicon single crystal wafer. The resolution is found to be better than 0.1° and can be easily improved by repetition of measurements. A test measurement on a BaFe2As2 thin film, where disorientations of 0.1° and less are present, was performed using the cross correlation electron backscatter diffraction technique. The same measurement is evaluated with the Hough transform technique. Comparing both techniques give evidence of a relative resolution of better than 0.1°. However, in specimen areas with strain inhomogeneities a deviation along one rotation axis can be observed. 相似文献
992.
Pablo A. Denis 《Molecular physics》2014,112(8):1167-1173
By means of coupled cluster theory and correlation consistent basis sets we investigated the thermochemistry of dimethyl sulphide (DMS), dimethyl disulphide (DMDS) and four closely related sulphur-containing molecules: CH3SS, CH3S, CH3SH and CH3CH2SH. For the four closed-shell molecules studied, their enthalpies of formation (EOFs) were derived using bomb calorimetry. We found that the deviation of the EOF with respect to experiment was 0.96, 0.65, 1.24 and 1.29 kcal/mol, for CH3SH, CH3CH2SH, DMS and DMDS, respectively, when ΔHf,0 = 65.6 kcal/mol was utilised (JANAF value). However, if the recently proposed ΔHf,0 = 66.2 kcal/mol was used to estimate EOF, the errors dropped to 0.36, 0.05, 0.64 and 0.09 kcal/mol, respectively. In contrast, for the CH3SS radical, a better agreement with experiment was obtained if the 65.6 kcal/mol value was used. To compare with experiment avoiding the problem of the ΔHf,0 (S), we determined the CH3–S and CH3–SS bond dissociation energies (BDEs) in CH3S and CH3SS. At the coupled cluster with singles doubles and perturbative triples correction level of theory, these values are 48.0 and 71.4 kcal/mol, respectively. The latter BDEs are 1.5 and 1.2 kcal/mol larger than the experimental values. The agreement can be considered to be acceptable if we take into consideration that these two radicals present important challenges when determining their EOFs. It is our hope that this work stimulates new studies which help elucidate the problem of the EOF of atomic sulphur. 相似文献
993.
Detailed finite element implementation is presented for a recently developed technique (He et al., 2012) to characterize nonlinear shear stress–strain response and interlaminar shear strength based on short-beam shear test of unidirectional polymeric composites. The material characterization couples iterative three-dimensional finite element modeling for stress calculation with digital image correlation for strain evaluation. Extensive numerical experiments were conducted to examine the dependence of the measured shear behavior on specimen and test configurations. The numerical results demonstrate that consistent results can be achieved for specimens with various span-to-thickness ratios, supporting the accurate material properties for the carbon/epoxy composite under study. 相似文献
994.
James M. Wallace 《力学快报》2014,4(2):022003
This paper reviews some of the principal uses, over almost seven decades, of correlations, in both Eulerian and Lagrangian frames of reference, of properties of turbulent flows at variable spatial locations and variable time instants. Commonly called space—time correlations, they have been fundamental to theories and models of turbulence as well as for the analyses of experimental and direct numerical simulation turbulence data. 相似文献
995.
Mohsen Doust Mohammadi Renjith Bhaskaran Hewa Y. Abdullah Hassan H. Abdallah George Biskos Somnath Bhowmick 《International journal of quantum chemistry》2024,124(1):e27288
We have investigated the potential energy curves (PECs) of the LiN heteronuclear diatomic molecule, including its ionic species LiN+ and LiN−, using explicitly correlated multi-reference configuration interaction (MRCI-F12) calculations in conjunction with the correlation consistent quintuple-𝜁 basis set. The effect of core–valence correlation, scalar relativistic effects, and the size of the basis sets has been investigated. A comprehensive set of spectroscopic constants determined based on the above-mentioned calculations are also reported for the lowest electronic states and all systems, including dissociation energies, harmonic and anharmonic vibrational frequencies, and rotational constants. Additional parameters, such as the dipole moments, equilibrium spin-orbit constants, excitation energies, and rovibrational energy levels, are also documented. We found that the three triplet states of LiN, namely, X 3∑−, A 3Π, and 2 3∑−, exhibit substantial potential wells in the PEC diagrams, while the quintet states are repulsive in nature. The ground state of the anion also shows a deep potential well in the vicinity of its equilibrium geometry. In contrast, the ground and excited states of the cation are very loosely bound. Charge transfer properties of each of these states are also analyzed to obtain an in-depth understanding of the interatomic interactions. We found that the core–valence correlation has a substantial effect on the calculated spectroscopic constants. 相似文献
996.
In this article,series of novel bi-SO3H-functionalized ILs were synthesized using simple,efficient and economic procedure. Hammett method had been used to determine the acidity order of these ionic liquids,and the acidities of bi-SO3H-functionalized ILs were stronger than that of traditional single-SO3H-functionalized ILs.Their catalytic activities in the synthesis of N-(3-phenyl)-3- oxo-l-(phenylpropyl)acetamide were investigated and they were consistent with their acidities. 相似文献
997.
998.
Péter Majlender 《Applied Mathematics Letters》2012,25(4):672-675
In 2005, Carlsson, Fullér and Majlender introduced a measure of possibilistic correlation of fuzzy numbers A and B by their joint possibility distributionC as an average degree of interaction between the γ-level sets of A and B as compared to their individual dispersions. They proved that this possibilistic correlation coefficient can never exceed 1 in absolute value, if all γ-level sets of the joint possibility distribution C are convex.In this communication, we shall formulate a special class of joint possibility distributions with non-convex γ-level sets, for which the correlation coefficient can take values outside the interval [−1,1]. In particular, this result will show that the assumption about the convexity of the level sets of C is essential for the possibilistic correlation to be bounded by the interval [−1,1]. 相似文献
999.
1000.