Enhanced Property of Thin Cuprous Oxide Film Prepared through Green Synthetic Route

Thin cuprous oxide films have been prepared by chemical vapor deposition (pulsed spray evaporation-chemical vapor deposition) method without post-treatment. The synthesis ofcuprous oxide was produced by applying a water strategy effect. Then, the effect of water on the morphology, topology, structure, optical properties and surface composition of the obtained films has been comprehensively investigated. The results reveal that a pure phase of Cu₂O was obtained. The introduction of a small quantity of water in the liquid feedstock lowers the band gap energy from 2.16 eV to 2.04 eV. This finding was mainly related to the decrease of crystallite size due to the effect of water. The topology analyses, by using atomic force microscope, also revealed that surface roughness decreases with water addition, namely more uniform covered surface. Moreover, theoretical calculations based on density functional theory method were performed to understand the adsorption and reaction behaviors of water and ethanol on the Cu₂O thin film surface. Formation mechanism of the Cu₂O thin film was also suggested and discussed.     

Optical analysis of polymer powder materials for Selective Laser Sintering

This study increases the basic understanding of optical material properties of polymer powders used in selective laser sintering (SLS). Therefore, different polymer powder materials were analyzed regarding their optical material properties with an integration spheres measurement setup. By the measurements a direct connection between the absorption behavior of the solid material and the overall optical material characteristics of the same material in powdery form could be shown. The results were used to develop an advanced explanation model for the optical material properties of powders. At present, existing explanation models only consider the occurring of multiple reflections in the gaps between the particles to explain the overall optical material properties of powder materials. Thus, by also considering the absorption behavior of the single particles, the basic understanding of the beam-matter interaction and their effect on the optical material properties of powder materials can be expanded.     

High‐performance segmented polyurea by transesterification of diphenyl carbonates with aliphatic diamines

In an effort to develop a green process for the production of elastomeric polyurethane–urea (PUaE) through a nonisocyanate route, a highly practical method was found using diphenyl carbonate (DPC) instead of diisocyanate as the carbonylation agent. The transesterification of aliphatic diamines in a solvent such as tetramethylene sulfone (TMS) with DPC results in a new process obtaining new segmented PUaE with high molecular weights and excellent mechanical performance. The key to the present success lies in the timing and sequence of the diamine addition forming initial carbamate intermediates in situ and then in shifting the equilibrium toward polyurea product formation by phenol removal from the TMS solution so that high‐molecular‐weight polyurea could be formed favorably. The most optimized polyurea films made in this study has a η_inh of 0.64, with high‐performance characteristics showing tensile strength of greater than 30 MPa and elongation exceeding 400% with decomposition temperature (5%) of >280 °C. Well‐defined soft‐ and hard‐segment domains were observed for the products as determined by atomic force microscope. This new improved process to produce segmented polyurea thereby complies fully with the principles of green chemistry using readily available chemicals. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2781–2790     

Synthesis of 3-aminoindan-1-one derivatives from 2-acetylbenzaldehydes and secondary amines by Mannich annulation

An acid-promoted 2-component Mannich annulation reaction of readily available acetylbenzaldehydes and secondary amines has been reported. The approach provides a simple and efficient method under mild conditions to synthesize 3-aminoindan-1-one derivatives in moderate to good yields.     

An efficient Fe(III)-catalyzed 1,6-conjugate addition of para-quinone methides with fluorinated silyl enol ethers toward β,β-diaryl α-fluorinated ketones

Reported here is a highly efficient 1,6-conjugate addition of fluorinated silyl enol ethers to para-quinone methides, allowing facile access to a range of β,β-diaryl α-fluorinated ketones with good to high yields. Fe(OTf)₃ was identified as the optimal catalyst, with the loading of 3?mol%. Notably, this represent the first 1,6-conjugate addition with fluorinated silyl enol ethers. The synthetic potential of the resulting adducts is also demonstrated.     

Histons: New Quasi-particles and Time-Resolved Fluorescence Shift of Polar Disordered Media

With statistical thermodynamics methods, it is shown that the evolution of a polar luminescence probe + polar disordered medium system after pulse excitation is described by an equation for damped vibrations. From this it follows that in the solvation shell of the excited solute probe, not only synchronous librations but also cooperative jump reorientations of solvent molecules take place, and their damping motion is caused by localized dielectric friction. This collective molecular dynamics is examined as the motion of a quasi-particle called a histon. The histon moment of inertia and mass are determined. The concept of l- and j-histons are also introduced. In terms of this model the full correlation functions for nonequilibrium solvent dynamics are derived. The behavior of steady-state and time-resolved spectra is examined and it is found that the limiting short-wavelength position of the steady-state spectrum at a low temperature and that for time-dependent fluorescence at t 0 are not identical. The histon model has been used for interpretation of the emission band collapse that is observed in long-time evolution experiments. Some other problems of spectral broadening are also discussed. As predicted, sharp expansion of the fluorescence band takes place on an ultrafast time scale due to dephasing of l-histons.     

The detection of cobalt by the microcosmic salt bead

I. The fact, that the blue violet colour of the microcosimic salt bead of cobalt is changed into blue by addition of Na₂CO₃ K₂CO₃, K₂CO₃ NA₂HPO₄ or NA₃PO₄is explained by the formation of pyrophosphate in the melt. II. K₂Na₂P₂O₇ if melted together with CoCl₂ forms blue porcelaneous masses, completely soluble in water.     

Supramolecular assemblies based on some new methyl-substituted cucurbit[5]urils through hydrogen bonding

Three supramolecular assemblies based on three new partial methyl-substituted cucurbit[5]urils, which are tetramethylcucurbit[5]uril (α,γ-TMeQ[5]), hexamethyl cucurbit[5]uril (α,β,δ-HMeQ[5]), Nonamethylcucurbit[5]uril (NMeQ[5]), were synthesized and structurally characterized by single-crystal X-ray diffractions. For the comparison with these new Q[5]s, crystal structure of an assembly constructing with normal Q[5] and K₂PtCl₆ was also reported. They are (α,γ-TMeQ[5])·15(H₂O) (1), (α,β,δ-HMeQ[5])·2Cl⁻·2(H₃O)⁺·7(H₂O) (2), (NMeQ[5])·14(H₂O) (3), (4). In the corresponding crystal structures, the molecular encapsulates included a water molecule and lidded water molecules at both of the portals were observed. Moreover, these molecular encapsulates are connected through hydrogen bonding and formed supramolecular chains or joined in pair.     

Synthesis of substituted 1,1′-diaminoferrocenes from cyclo-2-pentene imines

Condensation of anilines and primary aliphatic amines with 3,4-diphenylcyclo-2-pentenone leads to the corresponding diphenylcyclopentene imines in good yields of 72-90%. Deprotonation of these aminocyclopentadiene tautomers and reaction with FeCl₂ leads to the synthesis of the respective 1,1′-diamino-3,3′,4,4′-tetraphenylferrocenes. Yields increase from 33% to 65% with a decrease in the steric bulk of the amine substituent. The observation that a successful conversion requires two equivalents of base is conceived on the basis of the discussed reaction mechanism. The molecular structure of 1,1′-dianilino-3,3′,4,4′-tetraphenylferrocene (3a), which was determined by single crystal X-ray analysis reveals a trans coordination of the two amine moieties with respect to the central Cp-Fe-Cp axis of the ferrocenyl backbone.     

卤化物固态电解质研究进展

全固态电池因其高能量密度和高安全性而成为具有发展前景的下一代储能技术。开发具有高室温离子电导率、优异化学/电化学稳定性、良好正/负极兼容性的固态电解质是实现全固态电池实用化的关键。卤化物固态电解质因其优异的电化学窗口、高正极稳定性、可接受的室温锂离子电导率等优势,受到了广泛的关注。本文通过对近年来卤化物电解质的相关研究进行总结,综述了该类电解质的组成、结构、离子传导路径及制备方法,并分析了金属卤化物电解质的电导率、稳定性特点,归纳了近年来该电解质在全固态电池中具有代表性的应用,并基于以上总结和分析,指出了卤化物固态电解质的研究难点及发展方向。