Formation of gold nanoparticles in gold ruby glass: The influence of tin

A ¹¹⁹Sn Mössbauer study was carried out of tin(IV) complexes with 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N(4)-methyl (H2Bz4M) and N(4)-phenyl (H2Bz4Ph) derivatives: [Sn(2Bz4DH)Cl₃] (1), [Sn(2Bz4DH)PhCl₂] (2), [Sn(2Bz4M)Cl₃] (3), [H₂2Bz4M]₂[Ph₂SnCl₄] (4), [Sn(2Bz4Ph)PhCl₂] (5), [Sn(2Bz4Ph)Ph₂Cl] (6), in which H2Bz4R stands for the neutral ligand and 2Bz4R stands for the anionic thiosemicarbazone. In addition, ¹¹⁹Sn Mössbauer studies of the tin(IV) complexes [Sn(H4Bz4DH)₂Cl₄H₂O] (7), [Sn(H4BzPS)₂Cl₄H₂O] (8) with 4-benzoylpyridine thiosemicarbazone (H4Bz4DH) and the correspondent semicarbazone (H4BzPS) were performed. The isomer shifts decrease upon coordination due to the variation in the percentage of s character as tin changes from approximately sp³ hybridization in the tin salts to sp³d² in the octahedral or sp³d³ in the heptahedral complexes. The Mössbauer parameters of compound (4) showed the existence of two tin(IV) sites, which have been attributed to the presence of the cis and trans isomers.     

Varieties with small discriminant variety

Let be a smooth complex projective variety, let be an ample and spanned line bundle on , defining a morphism and let be its discriminant locus, the variety parameterizing the singular elements of . We present two bounds on the dimension of and its main component relying on the geometry of . Classification results for triplets reaching the bounds as well as significant examples are provided.

     

Compton散射对磁化等离子体光子晶体缺陷模密温特性的影响

应用多光子非线性Compton散射模型和有限时域差分法,对Compton散射对磁化等离子体光子晶体缺陷模密温特性的影响进行了理论分析和数值模拟。结果表明,与Compton散射前的情况相比,Compton散射使低温低频处光子禁带中存在缺陷模的明显度降低,缺陷模频率增大,缺陷模和透射率峰值减小;使高温高频处缺陷模和透射率峰值、缺陷模频率显著增大,禁带宽减小,缺陷模位置向高频方向移动。随着电子密度的增大,散射减小了禁带增大效应和缺陷模减小效应,增强了缺陷模频率增大效应;随着电子密度的降低,散射增强了禁带变窄效应、缺陷模峰值增大效应和缺陷模频率减小效应。利用Compton散射,可实现对缺陷模密温特性的有效控制。     

Ortho‐Trialkylstannyl Arylphosphanes by C–P and C–Sn Bond Formation in Arynes

A novel and efficient approach to ortho‐trialkylstannyl arylphosphanes by the reaction of arynes generated in situ with stannylated phosphanes (R₃Sn? PR₂) is described. Concurrent C? P and C? Sn bond formation occurs with high yields, and stannylated products are easily transformed into valuable ortho‐substituted arylphosphanes. The reaction features high efficiency, good regioselectivity, and excellent practicality.     

Synthesis of di-μ-oxo-tetra-(α-pentyloxy)tin(Ⅳ)phthalocynine

Axially substituted tin phthalocyanines, namely dichloride-tetra-(pentyloxy) tin (IV) phthalocyanine 3 and its dimmer di-cyanine 4 were synthesized. The catalytic effect of H2O-free CaCl2 in quinoline was used for condensation of dihydroxy tin phthalocyanine 3 to the cofacially array dimmer 4. Their structures were characterized by UV-vis, IR, elemental analysis, MS, as well as 1HNMR spectroscopy.     

Formation Enthalpy Calculation of Oxygen Vacancy Defect in Doped Lithium Niobate Crystals

The relationship between temperature and oxygen vacancy concentration is deduced in this paper. Based on the data of thermal weight-loss experiment, the formation enthalpies of congruent and several doped LN crystals have been calculated. It was found that the formation enthalpy of oxygen vacancies can be decreased evidently by doping valence-changeable ions. The experimental results were discussed and a new reduction process of the photorefractive LN crystal at a relatively low temperature was proposed, and the reduced crystals showed a good effect in practical use.     

Greater insight into the MTDSC technique involving fundamental sinusoidal heat flow equations

Summary Modulated temperature DSC was investigated, comparing data found experimentally to that derived from theory. Deviation from theory was found with regard to the amplitude of the modulated heat flow signal when large modulation amplitudes were employed in the experiment. These deviations were determined to be dependent on the absolute temperature and it was concluded that further investigation of the heat flow signal obtained during MTDSC experiments is required.     

Untersuchungen über Zinn(IV)-alkoxide. II. Isolierung und Charakterisierung der Verbindung Sn3O(OiBu)10 · 2i-BuOH. Das erste Beispiel für ein partielles Hydrolyseprodukt eines Zinn(IV)-alkoxids

Investigations into Tin(IV) Alkoxides. II. Isolation and Characterization of the Compound Sn₃O(OⁱBu)₁₀₁₀ · 2i-BuOH. The First Example of a Partially Hydrolized Tin(IV) Alkoxide The partial hydrolysis product Sn₃O(OⁱBu)₁₀ · 2i-BuOH was obtained by slow hydrolysis of the reaction product of tin tetrachloride with sodium isobutoxide. The compound forms colourless, moisture sensitive crystals, which easily release the coordinated solvent molecules in dry air. Its crystal and molecular structure has been determinated by single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P1 with a = 1363.5(7), b = 1462.7(10), c = 1637.7(7) pm, α = 95.40(5)°, β = 96.79(4)°, γ = 102.12(5)° and Z = 2. The crystal structure consists of discrete, trimeric molecules with octahedrally coordinated tin atoms which are connected to each other corresponding to the formulation Sn₃(μ₃-O)(μ₂-OⁱBu)₃(O¹Bu)₇ · (i-BuOH)₂ by three isobutoxide groups bridging two metal atoms and a single threefold bridging oxygen atom