Six series of styrene derivatives XCH═CHArY (total of 65) containing the styrene parent molecular skeleton were synthesized (here, Y is OMe, Me, H, F, Cl, CF3, CN, and NO2, and X is 2‐furyl, 3‐furyl, 2′‐methyl‐2‐furyl, 2‐thienyl, 3‐thienyl, and 2′‐methyl‐2‐theniyl). Their ultraviolet absorption spectra were measured in anhydrous ethanol, and their wavelength of absorption maximum λmax was recorded. For the wavenumber νmax (cm?1, νmax = 1/λmax) of the obtained λmax, a quantitative correlation analysis was performed, and 6 excited‐state substituent constants of groups X were obtained by means of curve‐fitting method. Taking the νmax values of total 90 compounds of styrene derivatives as a data set (including 25 compounds from reference and 65 compounds of this work), a quantitative correlation analysis was performed, and the reliability of the obtained was verified. In addition, 12 samples of disubstituted Schiff bases (XCH═NArY) involving the above groups X were synthesized, and their νmax values were recorded. Using these 12 νmax together with the 14 νmax values of Schiff bases taken from reference (total of 26 compounds), it was further verified that the values are reliable by means of quantitative correlation method. 相似文献
We prepared and investigated grain boundary Josephson junctions based on SrTiO3 bicrystal substrates. During the deposition of YBa2Cu3O7–δ (YBCO) gold nanocrystals forming from an intermediate gold layer can modify the crystalline structure and thus the properties of the YBCO grain boundaries. The variation of the film thickness of the Au seed layer changes the growth conditions of the YBCO film and the Au nanocrystals. The values of the characteristic ICRN product do not change whereas the values of the critical current IC decrease.
LSS based computed electronic stopping power values have been compared with the corresponding measured values in polymers for heavy ions with Z = 5–29, in the reduced ion velocity region, vred ≤ 1. Except for limited vred 0.6–0.85, the formulation generally shows significantly large deviations with the measured values. The ζ factor, which was approximated to be Z11/6, involved in LSS theory has been suitably modified in the light of the available experimental stopping power data. The calculated stopping power values after incorporating modified ζ in LSS formula have been found to be in close agreement with measured values in various polymers in the reduced ion velocity range 0.35 ≤ vred ≤ 1.0. 相似文献
The minimal Standard Model exhibits a nontrivial chiral U(2) symmetry if the VEV and the hypercharge splitting Δ = (y-y)/2 of right-handed leptons (quarks) in a family vanish and Q = T0 + Y independently in each helicity sector. As a generalization, we start with SU(2)L × SU(2)R × U(1)(B-L) and introduce Δ as a continuous parameter which is a measure of explicit symmetry breakdown. Values 0 ? Δ ? 1/2 take the neutral generator of the isospin ½ representation to the singlet representation, i.e. ‘deformes’ the LR representation into the minimal Standard one. The corresponding classical O(3)-breaking term is a magnetic field perpendicular to the x3-axis. A simple mapping on the fundamental Drinfeld-Jimbo q-deformed SU(2) representation is given. 相似文献
Quantitative optical spectroscopy measurements of the emission spectra of the N(B2∑u,)ν′→X2∑gν″ transition (first negative system) in an Ar-N2 microwave discharge at atmospheric pressure have allowed determination of the rate coefficient of the production of N molecules in the B2 ∑u, state with vibrational level ν′ = 0. The N(B2∑u, ν′) molecules are produced by the reaction in a surface-wave-induced microwave discharge (2450 MHz) sustained in an open-ended dielectric tube. The rate coefficient K (T) has been obtained for ν′ν″ = 0 for different gas temperatures by varying the incident microwave power. The K00(T) values are between 7.10?10 and 4.10?10 cm3 s?1 for the temperature range 2500 to 3450K. 相似文献
The matrix elements for the hyperfine structure of the configuration lll in SL-Kopplung are expressed as linear combinations of the electron coupling constants αli(10), αli(01), αli(12). 相似文献
Recent results of the characterisation of the structure, morphology and orientation of fine-scale, strengthening precipitate phases in selected magnesium alloys using transmission electron microscopy and microdiffraction are reviewed. The strengthening precipitate phases in Mg–Y–Nd alloys, aged to maximum hardness at 250°C, have been found to include two metastable precipitate phases β′ and β1, and the equilibrium precipitate β. The β′ phase has a globular form, a base-centred orthorhombic structure (potential point group of mmm), and an orientation relationship such that (100)β′//(1
10)α, [001]β′//[0001]α. The β1 phase has an f.c.c. structure (space group
and an orientation relationship that may be described by
(100)β1//[0001]α, and forms as plates parallel to
The β phase has an f.c.c. structure (space group
) and also forms as plates on
with an orientation relationship with the matrix phase that is identical to that observed for β1 phase. Precipitates in Mg–Al alloys, aged isothermally at 200°C, invariably have the b.c.c. structure of the equilibrium precipitate phase β (Mg17Al12). Three orientation relationships have been observed between β and the matrix phase. Most precipitates have an irrational orientation relationship that approximates to the Burger's relationship, (001)β//(0001)α,
and a faceted lath morphology with habit plane parallel to (0001)α. A minor fraction of precipitates posses an orientation relationship that is of the form
Full-size image
and have a prismatic rod morphology. The long axes of these rods are parallel to [0001]α, and their faceted surfaces are parallel to
A few precipitates are observed to have an orientation relationship such that
Full-size image
and a rod shape, with their long axes apparently inclined with respect to [0001]α. 相似文献
The radial profiles of KT-1 tokamak (major radius of 27 cm, minor radius of 4.25 cm, two poloidal stainless-steel limiters) edge plasma parameters are measured using single and triple electric probes. The particle transport parameters are calculated from the measured edge plasma parameters, and the results are analyzed by the simple fluid approximations. The cross-field particle diffusion coefficient (D) in the boundary plasma of the KT-1 is calculated from the density scrape-off length (λn) measured by using a triple probe. The particle density and electron temperature fall exponentially in the radial direction with the e-folding length of λn=0.13 cm and λe=0.41 cm, respectively. From the scrape-off layer (SOL) model, the experimental values of scrape-off length (λn) is used to calculate the cross-field diffusion coefficient (D=1.2×103cm2/s), roughly corresponding to one third of the typical Bohm value. A simple SOL model with the contribution of recombination is introduced to evaluate the Bohm diffusion in the KT-1 tokamak edge plasma. Cross-field heat conductivity calculated from these deduced values is 5.2D in the SOL of KT-1 edge plasma. These results provide the finally certain information for edge particle transport in the KT-1 boundary plasmas. 相似文献