Jiangxi University of Science and Technology

About: Jiangxi University of Science and Technology is a education organization based out in Ganzhou, China. It is known for research contribution in the topics: Microstructure & Alloy. The organization has 6958 authors who have published 5576 publications receiving 50650 citations.

Oxidative oxy-cyclization of 2-alkynylbenzamide enabled by TBAB/Oxone: switchable synthesis of isocoumarin-1-imines and isobenzofuran-1-imine.

Abstract: A TBAB-catalyzed oxidative 6-endo-dig oxy-cyclization of 2-alkynylbenzamide is described herein for the synthesis of isocoumarin-1-imines. The transformation proceeds regioselectively and provides the final products with high efficiency and a broad reaction scope. Interestingly, an array of isobenzofuran-1-imines is also achieved under standard conditions when N-phenyl 2-trimethylsilylethynylbenzamides are used as substrates. Mechanism studies show that 3-bromomethenisobenzofuran-1-imine is a pivotal intermediate, which goes through C–O bond migration and debromination to offer the final isocoumarin-1-imines.

Accurate Density Calculation for Molten Slags in SiO2–Al2O3–CaO–MgO Systems

Abstract: Density is one of the fundamental physical-chemistry properties for molten slags. It plays crucial roles in a lot of unit processes of pyrometallurgy, including metal-slag separation, slag foaming, heat transfer, etc. Due to the technical difficulties and high cost of density measurement at high temperatures, it is worthwhile to develop an accurate model for density calculation. The density is proportional to reciprocal volume, hence most of the density models are based on different ways to represent the molar volume. In the early stage of density modeling, Bottinga and Weill1) proposed an additive model based on the idea of constant partial molar volume of each component. The model was further revised by taking into the consideration of composition dependence of partial molar volume,2) and found much higher accuracy. After that Mills and Keen3) also proposed a model in which partial molar volume of Al2O3 and SiO2 are polynomial functions of composition. Since then many density models have been developed. A brief summary of these models was presented in Table 1. It can be found that in all density modelings, a common key issue is the description of composition dependences of partial molar volume. Generally, it can be described by the concept of excess molar volume,4–10) geometric model,11–13) optical basicity14,15) or thermodynamic models.16–21) An ideal density model for molten slags should cover Accurate Density Calculation for Molten Slags in SiO2–Al2O3– CaO–MgO Systems

Reversible phase transition and switchable dielectric behaviors triggered by rotation and order-disorder motions of crowns

Abstract: Solid-to solid-state reversible phase transitions are widely used in switchable dielectrics, ferroelectrics, piezoelectrics, and pyroelectric and non-linear optical materials. Herein we report a new crown ether clathrate, [Habf-(18-crown-6)1.5]+ [PF6]- (Habf = p-ammonium benzene formamide) which shows an interesting reversible phase transition near room temperature (263 K). X-ray single crystal diffraction analysis shows that the synergetic rotation motion between the 18-crown-6 crown ethers and the order-disorder motions of both hexafluorophosphate guest anions and 18-crown-6 crown ether host molecules lead to the phase transition. This reversible phase transition is confirmed by an evident thermal anomaly behavior around 263 K. The apparent step-like dielectric change around the phase transition indicates that it has potential application in dielectric switches.