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The effect of ZnO on phase composition, microstructure, thermal and dielectric properties of AlN ceramics was studied. The X-ray diffraction indicated that ZnAl2O4 and ZnO phases were detected in samples. With 0.5 wt% ZnO added, the thermal conductivity of AlN sample increased to 193.7 W/m·K. Whereas, the thermal conductivity dropped sharply due to excess ZnO. Moreover, the addition of ZnO increased the permittivity and altered the relaxation mechanism of AlN ceramics. The fitting data and activation energy from impedance spectroscopy revealed the variation of defect mechanisms in samples. The addition of 0.5 wt% ZnO reduced the concentration of aluminum vacancy in AlN grains to improve thermal conductivity. Nevertheless, excess ZnO dissolved into the AlN lattice and created additional defects, causing the decrease in thermal conductivity and electrical resistivity for AlN ceramics. Overall, suitable addition of ZnO can effectively increase the thermal conductivity and alter the dielectric properties of AlN ceramics. [ABSTRACT FROM AUTHOR]

An energy-saving complex distillation column, can separate ethyl acetate and isopropanol from pharmaceutical waste water. This allows reducing energy consumption and improve economically efficiency, was proposed by this article. According to the requirements of industrial carbon emission reduction, carbon tax and carbon emission rate, were added to the calculation of total annual cost (TAC). Based on Aspen Plus simulation, carbon emission reduction as a comprehensive optimization objective to optimize the process. The optimization results show that process is more energy-saving than traditional processes, the reboiler duty and TAC are respective reduced by 44.96% and 52.93%, and the carbon emission reduction is calculated accurately. This study provides the design and theoretical basis for the industrialization of similar organic matter separation process. [ABSTRACT FROM AUTHOR]

45wt%Ba0.55Sr0.45TiO3-55wt%MgO composites prepared by heterogeneous precipitation method and sol-gel method were synthesized. Coating layer was obviously observed in the calcined BST/MgO particles prepared by heterogeneous precipitation method and sol-gel method, but it disappeared in the composites after sintering because of the grain growth of MgO. Compared to the sample prepared by conventional solid-state reaction method, higher tunability and higher dielectric constant while lower dielectric loss was achieved in the BST/MgO composites prepared by heterogeneous precipitation method and sol-gel method. This result was attributed to the difference of Mg element content in BST grain. This study shows that using the heterogeneous precipitation and sol-gel method effectively improved the properties of the BST/MgO composites. [ABSTRACT FROM PUBLISHER]

The effect of raw material on properties of Ba0.55Sr0.45TiO3/MgO composites was studied. The Ba0.55Sr0.45TiO3was prepared by BaCO3, SrCO3, TiO2and BaTiO3, SrTiO3. The MgO was prepared by heavy magnesium oxide, light magnesium oxide and basic magnesium carbonate, respectively. The crystalline phases of all ceramics were the same. Whereas, the grain size, lattice parameters, microwave dielectric properties and tunability of the samples were different. Overall, the Ba0.55Sr0.45TiO3/MgO composites, in which BST were prepared from BaCO3, SrCO3and TiO2, and MgO was prepared by heavy magnesium oxide, exhibited excellent properties ofϵr= 141.55,Q × f= 905 GHz and nr= 7.16% (E = 3 kV/mm). [ABSTRACT FROM PUBLISHER]

This paper presents an adaptive mesh refinement (AMR) algorithm to solve the non-isothermal multiphase flows in heterogeneous porous media comprising different rock types. To address the discontinuity coming from different rock types, we found that the ratios of relative permeability and oil-gas capillary pressure are continuous; hence they are chosen as the judging values for the regridding purpose. Moreover, because of the tensorial permeability and the complex topology of the AMR grid, a coupling flux solution based on the multipoint flux approximation was carefully designed. Numerical examples revealed the accuracy and efficiency of the proposed AMR algorithm. [ABSTRACT FROM PUBLISHER]

The Donryu rat strain is a commonly used model for endometrial cancer disease study. We sequenced this rat strain mitochondrial genome for the first time (GenBank Accession No. KM114605). Its mitogenome was 16,307 bp and coding 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes. A total of 96 SNPs were examined when compared to reference BN sequence. [ABSTRACT FROM PUBLISHER]