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High silica content SAPO-5(d) with an AFI topology has been synthesized by dry-gel conversion (DGC) method. Various techniques have been used to characterize the structures of molecular sieves. XRD patterns show high crystallinity and purity of the DGC samples. XRF analyses prove high silica content of SAPO-5(d). The SAPO-5(d) has small particle size of 0.5–1 μm with large BET surface area. Co-SAPO-5-0.6(d) exhibits a high activity for the epoxidation of alkenes with air to achieve 94.5 mol% conversion of styrene and 87.2% selectivity of epoxide. Recycling studies and control experiments show the recyclable stability of Co-SAPO-5-0.6(d) as a heterogeneous catalyst. As a comparison, SAPO-5(h) samples by hydrothermal synthesis (HTS) method have also been prepared and applied in the epoxidation reaction. However, the catalytic activity of Co-SAPO-5- x (d) (82.2–94.5 mol%) is higher than that of Co-SAPO-5- x (h) (72.9–85.5 mol%), which can be correlated with high silica content, high cobalt content, small particle size and large surface area. [ABSTRACT FROM AUTHOR]

Abstract: The Mn2+-exchanged zeolites Mn-Y, Mn-beta, Mn-A and Mn-ZSM-5 were prepared and used as heterogeneous catalysts for the liquid phase epoxidation of alkenes with aqueous hydrogen peroxide (30% H2O2) at 273–298K in the NaHCO3 buffer system. The structures of catalysts were characterized by powder X-ray diffraction (XRD), UV–vis, ICP, BET and IR techniques. Mn-beta and Mn-Y exhibited the best recyclable activity for the epoxidation of styrene to achieve styrene conversions higher than 96.0 and 98.5mol%, respectively. Mn-beta showed higher activity for cyclohexene and norbornene but lower activity for α-methylstyrene, cinnamyl chloride, indene, cyclooctene and α-pinene than Mn-Y, which could be correlated with the difference of their pore sizes. However, these catalysts did not show any activity for the epoxidation of 1-octene with H2O2, possibly due to low electron density of double bonds of linear terminal alkenes. [Copyright &y& Elsevier]

Abstract: An effective route was first developed to heterogenize active C5H5NiLX complex for the preparation of the solid catalyst ▪. The attachment of the nickel complex onto the polymer was carefully characterized by IR, solid diffuse reflectance UV–vis, 31P CP MASNMR spectra and ICP-OES elemental analysis, which proved that the present route was relatively simple and effective for the immobilization of active centers, and that the materials used was considerably cheap. Thus-prepared solid catalyst ▪ showed high activity, selectivity and an excellent recyclability for the hydrosilylation of alkenes with trichlorosilane at mild conditions, outstandingly overcoming the problem of homogeneous system. This is a key success to provide a new methodology for heterogenizing active homogeneous components. [Copyright &y& Elsevier]

A total of 255 corn samples collected in 2010 from three main corn production provinces of China (Liaoning, Shandong, and Henan) were analyzed for contamination with fumonisins (FB1 and FB2). The incidence of contamination was significantly higher in samples from Liaoning than in samples from the other two provinces. Approximately 80.0% of the samples from Liaoning were contaminated with fumonisins, with a mean total fumonisin concentration of 3,990 ng/g. In contrast, the mean total fumonisin concentrations were 845 and 665 ng/g in samples from Shandong and Henan, respectively. The probable daily intake of fumonisins (0.3 µg/kg of body weight) is within the provisional maximum tolerable daily intake of 2.0 µg/kg of body weight set by the Joint Food and Agriculture Organization and World Health Organization Expert Committee on Food Additives. [ABSTRACT FROM AUTHOR]

Abstract: ZSM-5, mordenite, cancrinite and Y zeolites were successfully crystallized by the dry-gel conversion (DGC) without any organic additive (or template), in which the crystal particles of ZSM-5, mordenite and Y zeolite were well controlled in the range of ultrafine size. With a molar ratio of SiO2/Al2O3 ≤40, the pure ZSM-5 zeolite was obtained at 170°C at the Na2O/SiO2 molar ratio <0.2, but the pure mordenite was formed at 150°C at the Na2O/SiO2 molar ratio >0.25. When the dry-gel with a composition of 5.0Na2O:Al2O3:5.0SiO2 was crystallized at 140°C for 24h, pure cancrinite phase was obtained. TEM images showed that thus-crystallized zeolites consisted of ultrafine particles ranging 35–150nm for ZSM-5, 50–200nm for mordenite and 120–200nm for zeolite Y, respectively. Different from ZSM-5, mordenite and cancrinite zeolites, the DGC synthesis of Y zeolite required more water in the dry-gel before crystallization. [Copyright &y& Elsevier]

Detection of malnutrition in dialysis patients is important since this is a predictor of morbidity and mortality. Lean body mass (LBM) reflects the somatic protein store and this was measured by creatinine kinetics, anthropometry, and biometric impedance in 210 incident Chinese patients on continuous ambulatory peritoneal dialysis. The study was started in the third month of dialysis and the patients were followed for an average of 29 months. We devised three models of survival by combining the three different LBM measures with several nutritional markers and recognized outcome predictors. Follow-up was censored for transplantation or transfer to hemodialysis with an end point of death while on peritoneal dialysis. Statistical correlations were observed among the LBM values determined by all the three methods and these correlated significantly with both left and right hand grip strength but not with nutritional markers. LBM by creatinine kinetics, mean arterial pressure, and the calcium–phosphorus product were significant, independent predictors of death in one survival model. Anthropometry and bioelectric impedance were not significant predictors of death in the other two models. Our study suggests that LBM measured by creatinine kinetics, anthropometry, and bioelectrical impedance correlates well with the somatic protein store but not with the general nutritional status.Kidney International (2008) 73, 334–340; doi:10.1038/sj.ki.5002644; published online 21 November 2007 [ABSTRACT FROM AUTHOR]

We studied the relationship between locations of retained austenite (RA) and the deformation behaviors of quenching and partitioning treated steels. By using a variety of quantitative characterization techniques and comparing ferrite and martensite dual-phase counterparts, we confirmed that the stability of RA within different matrix phases is largely dependent on the plastic incompatibility between ferrite and martensite phases. If there exists significant difference in strength between ferrite and martensite, the transformation of RA is discontinuous. The RA inside ferrite and martensite transforms under low and high strain, respectively. As a result, deformation behaviors of the matrix phases, especially the ferrite phase at low strain, can be substantially affected by the change of RA. Our analysis offers insight into the interactions among different phases, the stability of RA, and the strain hardening behavior of multi-phase steels. [ABSTRACT FROM AUTHOR]