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To alleviate agglomeration and refine the particle size, a novel sol-gel-flux method (SGFM) was applied to synthesise ZrO2 (1Y6Ce–ZrO2) nanoparticles (NPs) stabilised by 1 mol% Y2O3 and 6 mol% CeO2. Both the NaCl and NaCl + KCl flux systems were investigated. The effects of calcination temperature and holding time on the phase composition and morphology of the NPs were studied, and the sintering performances of the 1Y6Ce–ZrO2 NPs prepared in the two flux systems were compared. The results showed that the optimum temperature for the preparation of 1Y6Ce–ZrO2 NPs by SGFM could be reduced from 800 to 700 °C if the NaCl system was replaced by the NaCl + KCl system. The lower calcination temperature resulted in well-dispersed tetragonal 1Y6Ce–ZrO2 NPs with an average grain size of 14.5 nm and quasi-spherical morphology. 1Y6Ce–ZrO2 NPs prepared in the NaCl + KCl system exhibited better sintering performance than 1Y6Ce–ZrO2 NPs prepared in the NaCl system. The 1Y6Ce–ZrO2 ceramics obtained by sintering the former showed higher stability at high temperatures, smaller grain sizes, and narrower grain size distributions, which are conducive to improving the mechanical properties of 1Y6Ce–ZrO2 ceramics. Fully tetragonal 1Y6Ce-TZP ceramic with an average grain size of 0.68 μm and a relative density of 98.49% were obtained by pressureless sintering of the former at 1400 °C for 2 h.

A novel dense diffusion barrier material (YxSr1−xTi0.9In0.1O3−δ (x = 0.03, 0.05, 0.07)) was prepared by using a sol-gel method. The crystal structure, microstructures, electrical conductivity and ionic conductivity of barrier material were characterized. The results show that the samples exhibit the formation of cubic perovskite structure phase. The increase of Y-doping amount on A-site improved electrical conductivity and sinterability of materials. A limiting current oxygen sensor based on Y0.07Sr0.97Ti0.9In0.1O3−δ as a dense diffusion barrier shows excellent sensing performance. The linear relationship between limiting current logIL and 1000/T can described logIL = 4.6038 − 3.8475·1000/T. At 750 °C, 0.25% ≤ x(O2) ≤ 5.0%, the linear relationship between limiting current (IL) and oxygen amount (x(O2)) can described as IL = 7.0476 + 3.8751 x(O2).

h -BN-SiC ceramic composites with different SiC contents were fabricated by spark plasma sintering. The results indicate that the addition of hard SiC particles has a remarkable effect on the densification, microstructure, mechanical properties and thermal shock resistance of the composites. Compared with pure h -BN ceramic, the relative density and mechanical properties of h -BN-SiC ceramic composites were improved obviously. The optimal properties of h -BN-SiC ceramic composites were obtained at SiC content of 25%, and the relative density, flexural strength and fracture toughness reached 97.8%, 289.2 MPa and 3.45 MPa m 1/2 , respectively. Moreover, the relationship of fracture toughness and fracture mode was discussed. The thermal shock test results showed that the h -BN-SiC ceramic composite with the SiC content of 25% exhibited excellent thermal shock resistance, presenting critical temperature difference up to 900 °C. The high temperature oxidation of h -BN and SiC on material surface led to the formation of borosilicate glass phase, which could heal the surface microcracks and then improve the thermal shock resistance.

We reported, for the first time, the fracture toughness of aluminum nitride ceramics at cryogenic temperatures. The fracture toughness increased from 3.98±0.19 to 4.59±0.28 MPa m 1/2 with the decreasing temperature from 293 to 77 K. Increasing fraction of transgranular fracture (from 7.3% at 293 K to 14.5% at 77 K) was proposed as a governing mechanism for toughness improvement at cryogenic temperatures based on the experimental observations. The effect of residual stresses on crack propagation was theoretically analyzed, considering energy release rates of intergranular and transgranular fractures. The variation of crack paths would contribute to the change of fracture modes and fracture toughness at cryogenic temperatures.

Three-dimensional quantitative structure activity relationship (3D-QSAR) studies were performed on Frusectose-1, 6-bisphosphatase (FBPase) inhibitors, based on molecular docking obtained by using GOLD and comparative molecular field analysis (CoMFA). Three random splits into training and test sets had been performed and the high leave-one-out (LOO) cross-validated correlation coefficients q(2) of 0.781, 0.725 and 0.801, respectively, revealed that the models are useful tools for the prediction of test sets as well as newly designed structures against FBPase activity. The superimposed CoMFA models on the receptor site of FBPase are guiding the design of potential inhibitory structures directed against FBPase activity. (C) 2011 Elsevier Masson SAS. All rights reserved.

In this study, the flexural strength of aluminum nitride (AlN) ceramics at cryogenic temperatures was reported for the first time. The flexural strength increased from 364.6±29.2 MPa to 415.3±21.7 MPa with temperature decreasing from 293 to 77 K. The strengthening mechanism was explored based on the Griffith equation for a brittle solid and was rationalized by the analysis of lattice constants of AlN and the Vickers indentation length at ambient and cryogenic temperatures. The increase of elastic modulus and fracture surface energy could contribute to the strengthening of AlN ceramics at cryogenic temperatures. The above results showed that AlN ceramics could be a promising candidate for cryogenic engineering.

Fibrotic processes in tissues are characterised by an excessive accumulation of collagen containing increased levels of pyridinoline cross-links, which has been taken as an important criterion to diagnose the fibrosis. Hypocrellin B (HB) is a natural photosensitizer with excellent photodynamic activity but very low dark-toxicity. In the current work, main purpose was to clarify if photodynamic action of HB could be applied to regulating the level of pyridinoline cross-link in collagen. To use gelatin as a model collagen, it was observed that the pyridinoline cross-link formation was effectively degraded by HB photodynamic action in the gelatin, suggesting the level of pyridinoline cross-link formation in collagen may be photodynamically regulated to a normal level. Furthermore, mechanism of the photodynamic action of HB was studied.

The oxidation of 2,3,6-trimethylphenol with Fenton’s reagent has been investigated under mild conditions in aqueous phase. 2,3,5-Trimethylbenzoquinone was obtained with a selectivity of nearly 99.9% at 100% conversion of 2,3,6-trimethylphenol at 45 ◦ C for 3 h. The different parameters like: the performance of different catalysts, the effect of catalyst concentration, reaction time, and reaction temperature has been investigated. Moreover, our new catalytic system was found also to be active in the oxidation of o-methylphenols to the corresponding benzoquinones by 5% H2O2 under mild conditions. In order to further study this reaction system, the possible mechanism was proposed. An important advantage of this catalytic system, apart from the organic solvent-free conditions, is that it is nontoxic, inexpensive and water-soluble.

A highly efficient oxidation of cyclohexane to cyclohexanone is accomplished over phenanthroline–CuCl2 catalyst in relatively mild conditions. This study realized nearly 100% selectivity for cyclohexanone at 24.4% conversion of cyclohexane. The reaction has been studied by various parameters like performance of copper(II) salts, effect of solvents, influence of bases, the ratio of o-phenanthroline: CuCl2, and reaction time. In order to further study this reaction system, the possible mechanism was proposed.

In this work, we have developed a simple and efficient approach to the degradation of organic dyes using ethylenediamine-CuCl(2) complex as the catalyst under basic conditions. Rhodamine B has been used as model compound and all experiments were carried out at normal atmospheric pressure and temperature (25+/-1 degrees C) under open-wide system. The different pH values from 7.0 to 14.0 and the catalyst recycling were investigated. The results indicated that ethylenediamine-CuCl(2) was an effective catalyst in the degradation of Rhodamine B at pH 7.0-12.0. It would provide a useful insight into the development of new routes in organic wastewater treatment.

Hypocrellin B, a photosensitizer isolated from Hypocrella Bambuase sacc in Yunnan province, has significant anti-tumor and anti-virus character. In this article, hypocrellin B, which was grafted on activated carbon, was used as photocatalysts to catalytic oxidize 2,3,5-trimethylphenol to 2,3,5-trimethylhydrobenzoquinone because of its high photons efficiency. This study realized nearly 100% selectivity for 2,3,5-trimethylhydrobenzoquinone under visible light irradiation (>400nm) at aerobic atmosphere. The photocatalytic oxidation process has been studied by different parameters like the pretreatment of activated carbon, synthetic mehtod of grafted hypocrellin, and photo-assisted oxidation catalysis of 2,3,5-trimethylphenol to 2,3,5-trimethylhdrobenzoquinone. Compared to the conventional methods, this process could be more eco-friendly.

In the current work, Hypocrellin A (HA) is one of the nature photosensitizer was recognized by researchers, and it used as a probe to research the molecular recognition and interaction with protein, the work suggested the HA can as the medicine to treat some disease. This paper study the spectrum character of photoreaction of Hypocrellin A and cysteine in different pH value, the spectrum show an isosbestic point at 495nm, and the absorption peak at 478nm was red-shifted to about 500nm. The result suggested the HA can react with cysteine in this condition, and farther illuminated the cysteine residue may is one of the target of the interaction of HA or HB with protein.

The title reaction afforded 2,3,5-trimethylbenzoquinone with a high selectivity (nearly 100%) at a 7.3% conversion of 2,3,5-trimethylphenol under irradiation with visible light (> 400 nm) in an aerobic atmosphere.