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1.
Crystallography Reports - Fluoride crystals K2(Ta0.9I0.1)F7 (sp. gr. Р21/c) complementary to the K2TaF7 and K2NbF7 fluoride family have been obtained by hydrothermal synthesis. Their...  相似文献   
2.
Crystallography Reports - The determination of 3D particle shapes from the one-dimensional data on small-angle scattering from macromolecule solutions is ambiguous. In addition, due to the poor...  相似文献   
3.
Crystals of new indium iodate (K0.6Na0.4Ba)In[IO3]6 were prepared by the hydrothermal synthesis. The unit-cell parameters are a = 11.3984(3) Å, с = 11.3817(3) Å, sp. gr. R3?. The chemical formula of the compound was derived from the structure determination and refinement with anisotropic displacement parameters to R = 0.0284. In the structure the InO6 octahedra share vertices with six umbrella-like [IO3]–groups typical of iodates and form isolated 3?-symmetric charged \(\rm{In[IO_{3}]_6^{3-}}\) clusters. Large Ba, K, and Na cations occupy a common site on a threefold axis due to the isomorphous substitution and compensate the charge of the clusters. The new structure extends the family of the recently discovered alkali-metal and barium iodates containing Ti and Zr atoms in octahedral sites. The iodate K2Ge[IO3]6 containing Ge atoms in the centers of octahedra is the parent compound of this structural family.  相似文献   
4.
The visible-light-induced arylation of tertiary phosphines with aryl(mesityl)iodonium triflates to produce the quaternary phosphonium salts occurs under mild, metal, and catalyst-free conditions. Photo-excited EDA complexes between diaryliodonium salts and phosphines supposedly enable this transformation, which is difficult to achieve through the traditional ground-state reactions. Demonstrating high functional group tolerance, broad scope, and complete selectivity of the aryl group transfer, the method is particularly compatible with sterically congested phosphines, which are challenging under metal-based catalytic methods.  相似文献   
5.
Crystallography Reports - The structures of Rb-boroleucite Rb1.0(B0.333Si0.667)3O6 and boropollucite Cs0.87(B0.290Si0.710)3O6 were studied using single crystals, which were prepared under...  相似文献   
6.
Crystallography Reports - A new polymer-inorganic nanocomposite composed of fibrous Na–Mg triple chain hydrosilicate with a poly(amide-imide) matrix was developed. Its structure, morphology,...  相似文献   
7.
Tikhonov  A. M.  Asadchikov  V. E.  Volkov  Yu. O.  Roshchin  B. S.  Ermakov  Yu. A. 《JETP Letters》2021,114(10):620-624
JETP Letters - The spectral properties of the correlation function of the heights of interlayer boundaries in a lamellar 1,2‑distearoyl-sn-glycero-3-phosphocholine film deposited on the...  相似文献   
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Possibilities of the experimental measurement and theoretical modeling of a fluorescence spectrum of a solid-anode X-ray tube are studied. A setup for the direct measurement of spectra of X-ray tubes of different types is created, spectra of a commercial BKh15 Svetlana X-ray tube are measured in wide range of anode voltages and currents. Calculations of spectra using the Ebel algorithm (Horst Ebel, 2006) with the parameters recommended in the original work ensure the satisfactory quality of the reproduction of the measured spectra, but demonstrate some statistically noticeable deviations. The optimization of model parameters ensures the improvement of the quality of simulation.  相似文献   
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