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The graphene oxide was prepared via one step under low-temperature with natural flake graphite as raw material. Factors affecting oxidation degree and layer spacing of graphene oxide were discussed in the process of low-temperature oxidation, such as the dosage of oxidant and oxidation time in system. The results indicate that high C-O bond and low defect structure (ID:IG=0.63) graphene oxide with the carbon and oxygen atom ratio of 1.98 can be prepared in the condition of the potassium permanganate with natural flake graphite mass ratio of 1:3, oxidation temperature of 0℃, oxidation time of 48h.This way avoids the increase of graphene oxide defects in the process of Hummers preparation due to the formation of CO2, which leads to the hexagon fracture and the absence of carbon atoms. After microwave reduction, the reduced graphene oxide with low defect is obtained, which the distance between defects(LD)is 12nm,the defect density(nD) is 2.21×1011cm-2 and the ratio of ID:IG is only 0.85 (ΓG=32.1cm-1).

Microwave and conventional heating were employed to synthesize micro-sized hematite powder from hydrous ferrous sulfate, a by-product in the process of titanium pigment manufacture. The TG/DTG analysis was used to study thermal behavior of the industrial ferrous sulfate. Therefore the temperature which was significant to product was defined. The calcination experiments were carried out to assess the effect of calcination temperature covering three different temperatures (650°C, 750°C and 850°C, respectively). X-ray powder diffraction (XRD) was used to characterize the structure of the product, while the scanning electron microscopy (SEM) was utilized to characterize the morphology of the product. Microwave calcination process resulted in a mixture of hematite and minor magnetite while a considerable amount of magnesium sulfate was detected with the conventional calcination process. The transformation from periclase to magnesium was discussed during the calcinations as well. The conventional heating resulted in porous product while the microwave heating resulted in smaller particle size.

The movement behavior of titanomagnerite ore material particles in rotary kiln was simulated by EDEM discrete element simulation software. The results show that the probability accumulation of particles will occur in the process falling down, and ricing again, forming discrete plies along the axis direction of the rotary kiln. The reaction area can be divided into nine fluctuation periods with an average period length of 0. 666 m. According to the calculation of enthalpy of endothermic reduction reaction, the fluctuation range of energy in a single cycle accounts for 29. 79% of the average value of enthalpy of reaction, and the average fluctuation energy in a single cycle of reaction time (500 s) is deduced as E=25.58 MJ, which is easy to cause energy instability. The direct reduction iron production can be carried out by attaching fine pulverized coal on the ore material particles, and using external coal pellets to reduce energy fluctuation by buffering local overheating. [ABSTRACT FROM AUTHOR]

LiNi1/3Co1/3Mn1/3O2 is a good solid solution system for LiNi1/3Co1/3Mn1/3O2. And it is compatible with the advantages of the three materials and makes up for the shortcomings of the above materials as the cathode materials. It is a popular cathode material for lithium batteries. The structural characteristics and electrochemical reaction characteristics of the cathode material are introduced. The research progress of layered LiNi1/3Co1/3Mn1/3O2 as cathode material for lithium ion batteries in recent years is reviewed and the the preparation methods of LiNi1/3Co1/3Mn1/3O2 is emphasized. The advantages and disadvantages of the preparation methods such as solid phase method, coprecipitation method and sol gel, as well as the effects of doping and surface-modification investigation on the electrochemical performance are summarized and compared. [ABSTRACT FROM AUTHOR]

Single-crystal diborate KSbOB2O5 has been prepared under a high temperature molten-salt method and its structure has been determined by single crystal X-ray diffraction analysis. The diffraction pattern shows strong main reflections and weak satellite reflections, clearly indicating a modulated structure. Using the four-dimensional superspace formalism for aperiodic structures, its reflections could be indexed as orthorhombic superspace group Pmn21(0β0)s00 with the modulation vector q = 5/12b*, and then the structure solution and refinement reached a final commensurately modulated model that was refined extremely well and did not show any unusual features. On the other hand, the powder sample of KSbOB2O5 was synthesized by the high-temperature solid-state reaction method, and the powder X-ray diffraction pattern fits very well with the simulated from the single-crystal data. In addition, photoluminescence properties of diborate KSbOB2O5 activated by 4.5 mol% Dy3+ have been studied, indicating an extraordinary phenomenon that the red emission at around 635 nm (4F9/2→6H11/2) is much stronger than the yellow emission at around 581 nm (4F9/2→6H13/2). [ABSTRACT FROM AUTHOR]

Abstract: This paper reports detailed investigation on the influence of microwave irradiation on the cobalt oxalate (Co(C2O4)·2H2O):cobalt oxide (Co3O4) systems in different mass ratio. The analyses of the spectra attenuation and relative frequency shift showed that Co(C2O4)·2H2O had weak capability to absorb microwave irradiation, while Co3O4 had good capability to absorb microwave irradiation. The ability to absorb microwave irradiation was also assessed based on the temperature raise of the system exposed to microwave irradiation. The capability to absorb microwave irradiation of Co(C2O4)·2H2O increased with an increase of ratio Co3O4 in system. [Copyright &y& Elsevier]

Single-crystal diborate KSbOB2O5 has been prepared under a high temperature molten-salt method and its structure has been determined by single crystal X-ray diffraction analysis. The diffraction pattern shows strong main reflections and weak satellite reflections, clearly indicating a modulated structure. Using the four-dimensional superspace formalism for aperiodic structures, its reflections could be indexed as orthorhombic superspace group Pmn21(0β0)s00 with the modulation vector q = 5/12b*, and then the structure solution and refinement reached a final commensurately modulated model that was refined extremely well and did not show any unusual features. On the other hand, the powder sample of KSbOB2O5 was synthesized by the high-temperature solid-state reaction method, and the powder X-ray diffraction pattern fits very well with the simulated from the single-crystal data. In addition, photoluminescence properties of diborate KSbOB2O5 activated by 4.5 mol% Dy3+ have been studied, indicating an extraordinary phenomenon that the red emission at around 635 nm (4F9/2→6H11/2) is much stronger than the yellow emission at around 581 nm (4F9/2→6H13/2). [ABSTRACT FROM AUTHOR]