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SnO2 is a theoretically excellent transformed anode material with high theoretical capacity for SIBs. However, SnO2 faces serious volume effect and high resistance, which greatly damages its electrochemical performance. Given that, the SnS−SnO2 heterostructures is constructed with special internal electric field, which is beneficial to promote the transfer ability of sodium ions. Besides, the graphene oxide (GO) modification is carried out to isolate the intrinsic materials from direct contact with electrolyte, and alleviate volume expansion of the anode, ultimately promote the electrochemical performance. Furthermore, the structure and the conductivity characteristics of SnS, SnO2, SnS−SnO2 and SnS−SnO2@ GO are simulated respectively by first principles and are compared with the correspondence experiment results to verify the accuracy of established models. Owing to the special p‐n junction in SnS−SnO2@GO heterostructures, the resistance of SnS−SnO2@GO can be reduced to 36.23 Ω, much lower than that of SnO2 (Rct=341.9 Ω). Notably, the combination of GO has effectively alleviated the volume expansion of SnS−SnO2@GO electrodes, and present excellent capacity higher than 384.7 mAh g−1 after 100 cycles. Thus, the efficient synthesis of SnS−SnO2@GO heterostructure electrodes with excellent performance for sodium storage is expected to provide valuable direction for SIBs anode materials. [ABSTRACT FROM AUTHOR]

The composition of fluoride‐containing mold fluxes changes when their melting point or viscosity are measured because the fluoride in the mold fluxes evaporates at high temperatures. Therefore, the measured melting points and viscosities are not those of the original fluxes, and thus, the results are not accurate. Therefore, evaluating the effects of evaporation is essential to accurately investigate the relevant properties. Herein, the chemical composition of the slag is determined using thermogravimetric analysis (TGA), roasting tests, and evaporation mechanism after the physical properties of the slag are measured using conventional methods. The measured melting point and viscosity are then matched with the modified slag composition instead of the original composition. This method is applied to different fluoride‐containing mold fluxes. The weight of the mold fluxes is reduced by more than 10% during the measurements, indicating that a large amount of the volatiles react and evaporate. The actual flux compositions corresponding to the observed melting point or viscosity of the mold fluxes are obtained through roasting test and TGA; therefore, one can easily match the measured mold flux properties to the flux composition. This study will help in determining other physical properties of slag and other melts containing volatiles. [ABSTRACT FROM AUTHOR]

In this study, crystallization behavior of an industrial mold flux was investigated using both single hot thermocouple technique (SHTT) and double hot thermocouple technique (DHTT). Continuous cooling transformation (CCT) and time-temperature transformation (TTT) diagrams were constructed using SHTT. The critical cooling rate in continuous cooling process was determined as 7 °C s−1 above which a glassy phase was formed. The TTT diagram showed two noses at approximately 1000 and 1075 °C. Phase identification carried out using X-ray diffraction (XRD) revealed that dicalcium silicate (Ca2SiO4) was the major phase at both 950 and 1100 °C, together with minor precipitates of Na2CaSi3O8 and Ca2MgSi2O7 whose concentrations were relatively higher at 950 °C. Cuspidine (Ca4Si2O7F2) was also identified by XRD at 950 °C. Crystallization kinetics was analyzed using Johnson-Mehl-Avrami-Kolmogorov equation. DHTT was used to simulate the temperature gradient between copper mold and strand in the continuous casting mold. Glassy phase was formed quickly near the cold side when it was quenched from 1500 to 800 °C. Crystals started to precipitate in the glassy region after 48 s. Then major part of the glassy region was gradually transformed to crystalline phase and the crystals subsequently grew to the liquid region. A steady three-layer state was reached after 360 s. [ABSTRACT FROM AUTHOR]

This paper investigated melting properties and viscosity of SiO2-CaO-Al2O3-B2O3 fluxes with a mass ratio of CaO/SiO2 from 0.83 to 1.5 and B2O3 content from 5 to 9 wt%. Melting properties of these fluxes were studied using the hot stage microscopy method; viscosity was measured using the rotating cylinder method. Break temperature was also determined from the viscosity change with temperature in flux cooling process. Equilibrium liquidus temperature was calculated using FactSage. Increase in CaO/SiO2 ratio was found to decrease hemispherical temperature and viscosity. The addition of B2O3 did not significantly affect hemispherical temperature but decreased the flux viscosity. Viscosity was analyzed in relation to the flux structure. The increase of the CaO/SiO2 ratio reduced the degree of flux polymerization, and B2O3 apparently acted as a weak network modifier under the low concentration of B2O3. The experimental viscosity was in a good agreement with calculated viscosity using the modified NPL model. [ABSTRACT FROM AUTHOR]

Development of fluoride-free mould flux is important for steel continuous casting. Properties of the mould flux depend on the flux crystallinity. This paper analyzes phase composition of fluxes containing B2O3, TiO2, Na2O, and MgO which can be feasible candidates to replace the fluorides. The phase equilibria of these fluoride-free boracic mould fluxes were calculated using the thermochemical software FACTSage. In the process of crystallization of the CaOSiO2Al2O3B2O3Na2O flux with high CaO/SiO2, combeite (Na2,Ca)Na2CaSi3O9, Ca11B2Si4O22, and nepheline NaAlSiO4 were formed, which can substitute cuspidine in the fluoride-containing fluxes. At high CaO/SiO2, adding MgO into CaOSiO2Al2O3B2O3Na2OTiO2 mould flux remarkably increased crystallization temperature by forming merwinite (Ca3MgSi2O8), decreasing the relative crystal phase contents of (Na2,Ca)Na2CaSi3O9 and Ca11B2Si4O22. The calculated data were in reasonable agreement with results of XRD and SEM/EDS analyses of selected boracic fluxes. [ABSTRACT FROM AUTHOR]

A multifunctional transition metal CdII coordination polymer based on an amide-inserted flexible multicarboxylate ligand, bis(3,5-dicarboxyphenyl)terephthalamide (H4L), [CdL] ·[+H2N(CH3)2] (DMF)(H2O)3 (MOF1) was synthesized by the solvothermal method. Its structure was determined by single-crystal X-ray diffraction analysis and it was characterized by elemental analysis, IR spectroscopy and thermogravimetric analysis. MOF1 shows selective sensitivity to detecting aniline pollutants in both aqueous media and as vapors due to its strong fluorescence emission and microporous structure. In addition, the visible-light-driven photocatalytic degradation of Rhodamine B (RhB) by MOF1 and polyaniline (PANI) composite material (named PANI/MOF1), which was prepared by loading PANI onto the surface of MOF1, was also studied. The results obtained illustrate that PANI/MOF1 exhibits improved photocatalytic activity over MOF1, which could be used to effectively treat wastewater containing organic dyes in the future. [ABSTRACT FROM AUTHOR]