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Lithium metatitanate (β-Li 2 TiO 3 ) pebbles were fabricated via the modified indirect wet chemistry method. Effect of varied additives, as polyvinyl alcohol, glycerol, and agar on the properties evolution was investigated. The highest density is obtained by adding 2 wt% (weight percent) polyvinyl alcohol, 3 wt% glycerol, and 3 wt% agar, respectively. β-Li 2 TiO 3 pebbles with relative sintered density of 92.4%T.D. (Theoretical Density), the ratio of the intensity of diffraction peak (002) to that of (−133) of about 2.93, about 1.58 mm in diameter, a better sphericity of 1.02, the particle size of 5–6 μm, and the well-developed surface layered structure are successfully fabricated with 3 wt% glycerol. Glycerol is beneficial to improving the properties by other fabrication method as well.

Mitomycin C (MMC) potently suppresses tumour growth. However, its use is limited by its severe toxicity to the kidney and bone marrow. The purpose of this study is to investigate whether the chemoprevention agent curcumin can reduce MMC-associated side-effects and improve MMC efficacy in a breast cancer xenograft model. We first determined the effectiveness of combined MMC and curcumin to inhibit in vitro cell growth and to regress in vivo tumour outgrowth. We then investigated the mechanisms associated with MMC/curcumin-induced cell death by examining the effect of MMC/curcumin treatment on apoptosis, the activation of caspase-3, 8 and 9 and the expression of bcl-2 and bax. We also evaluated the ability of curcumin to alleviate MMC-associated side-effects by comparing the levels of creatinine/blood urea nitrogen (Cr/BUN) and glutamic oxalacetic transaminase/glutamic pyruvic transaminase (GPT/GOT) in serum between animals receiving MMC alone and MMC/curcumin. Curcumin significantly sensitised MCF-7 and MDA-MB-231 cells to MMC-induced cell death and improved MMC's ability to regress MCF-7 xenograft. MMC and curcumin together synergistically enhanced apoptosis in MCF-7 cells and the apoptosis most likely resulted from both the activation of caspases and modulation of bcl-2/bax expression. Most importantly, the inclusion of curcumin in MMC treatment decreased MMC-caused severe side-effects evidenced by significant improvement in the kidney function. Enhancing the tumoricidal effect of MMC, curcumin greatly reduces MMC-associated severe side-effects. Therefore, the combination treatment of MMC and curcumin may be of significant therapeutic benefit in treating breast cancer.

The effects of crystallization on the corrosion resistance of a Cu52.5Ti30Zr11.5Ni6 bulk amorphous alloy in 1 mol/L HCl, and 6 mol/L NaOH solutions were studied. The amorphous alloy was identified by differential thermal analysis(DSC) and by X-ray diffraction(XRD). The partially and fully crystallized alloys were prepared by controlling the annealing temperatures at 738 and 873 K for 1 and 12 min, respectively, and the corrosion resistances of those annealed alloys were compared with that of the amorphous alloy by immersion test and potentiodynamic measurements in 1 mol/L HCl and 6 mol/L NaOH solutions. The results show that the partially crystallized alloy exhibits high corrosion resistance, whereas full crystallization results in deteriorated corrosion resistance compared with that of the as-cast amorphous alloy.

The diffusion bonding of γ-TiAl alloy to Ti-6Al-4V alloy at different temperatures ranging from 1 073 to 1 173 K under an applied stress of 100 MPa for 2 h was studied. The observation of the microstructure reveals that sound joints between the γ-TiAl alloy and the Ti-alloy without any pores or cracks can be achieved through diffusion bonding at temperatures over 1 073 K under the applied stress of 100 MPa for 2 h. The bond is composed of two zones, and its width increases with the increase of bonding temperature. The EDS chemical composition profiles indicate that there is a diffusion flux of Al atoms from γ-TiAl alloy towards the Ti alloy and of Ti atoms in the opposite direction. The three point-bending of the joints bonded under different conditions was tested and the fracture mode was analyzed by SEM observation.

Pure Bi 2 SiO 5 powders were synthesized by molten salt method in NaCl–Na 2 SO 4 flux using Bi 2 O 3 and SiO 2 as raw materials. The results showed that the pure metastable state compound Bi 2 SiO 5 was obtained in NaCl–Na 2 SO 4 flux at 625 °C for 1 h, which was lower than that (generally 750 °C) of conventional solid state reaction. X-ray diffraction revealed that in the case of NaCl–Na 2 SO 4 molten salt, with increasing synthesis temperature (600 °C to 625 °C), stable state Bi 12 SiO 20 transformed into metastable state Bi 2 SiO 5 and with synthesis temperature increasing from 625 °C to 700 °C, metastable state Bi 2 SiO 5 transformed into stable state Bi 4 Si 3 O 12 gradually. Therefore, calcination temperature played a crucial role in the formation of Bi 2 SiO 5 powder. The field-emission scanning electron microscopy images disclosed that the Bi 2 SiO 5 samples showed nest like morphology, which was soft aggregation of Bi 2 SiO 5 nanosheets. Moreover, it also indicated that the mechanism of the process of molten salt synthesis was “dissolution–precipitation mechanism”.

Pure Bi 2 SiO 5 crystals were firstly prepared by a novel method of melt-cooling process with Bi 2 O 3 and SiO 2 as starting materials. In this study, the preparation and properties of the samples were characterized by thermo gravimetric (TG), differential scanning calorimeter (DSC), field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The results showed several endothermic valleys at 579.6 °C, 744.3 °C, 829.3 °C and 879.2 °C during heating process; and a distinct exothermic peak at 805.3 °C during the melt cooling process. XRD and SEM images revealed highly-ordered lamellar pure Bi 2 SiO 5 crystals with coarse grains can be achieved by 2 h heating at 805.3 °C.

A new copper (II) complex [Cu(dtne)] · (ClO4)2 · CH3CH2OH, where dtne is 1,2-bis(1,4,7-triaza-1-cyclononyl)ethane, was prepared and characterized by X-ray crystallography. The result shows that in the complex the copper (II) adopts an octahedral coordination geometry. The cyclic voltammetry of the complex recorded in aqueous solution indicates a reversible one-electron redox reaction. The activity of dismutation of superoxide ( O 2 - ) of the complex in the riboflavin–methionine–nitro blue tetrazolium assay has been researched.

Self-tuning regulators have been successfully applied to two installations in a chemical plant. A self-tuning regulator for liquid level in the acetic acid evaporator went into formal use in April 1979; a self-tuning regulator for temperature in the central part of a vinyl acetate synthesis reactor went into operation in July 1979. Both regulators show marked improvement over PI-regulators