Effects of Steaming and SiO2 Surface Passivation on SSZ-13 Zeolites in the Ethylene to Propylene Reaction.

SSZ-13 zeolite was modified by two kinds of post-treatment methods such as steaming and SiO2 surface passivation (silylation) for ETP catalyst with high activity. The former steaming treatment was conducted in the range of 400-700 °C, whereas the latter surfaces passivation was applied to a chemical liquid deposition (CLD) technique that uses various silylation agents such as tetramethylorthosilicate (TMOS), tetraethylorthosilicate (TEOS), and tetrabuthylorthosilicate (TBOS). Catalysts were characterized by powder-XRD, ICP, Ar-phsisorption, solid-state 27Al MAS NMR, and NH3-TPD, and their activities were tested in fixed bed reaction system. Regarding the effects of steaming temperature, the results show that a relatively higher selectivity is observed in SSZ-13 catalysts treated at proper steaming temperatures such as 450 and 500 °C compared to parent and other steam treated catalysts. For optimum surface passivation treatments for ETP reactions, one-step surface passivation using TEOS agents among various passivation agents led to enhanced propylene selectivity to 80% when compared with parent and other silylated SSZ-13 catalysts. However, a sequential passivation treatment with a TEOS agent was not highly affected by the reaction activity.

Effects of Zeolite Supports on the Production of Fuel-Range Hydrocarbons in the Hydrotreatment of Various Vegetable Oils with Platinum-Based Catalysts.

The effects of catalyst supports on catalyst performance in the hydrotreatment of vegetable oils (to produce fuel-range hydrocarbons such as gasoline, jet fuel, and diesel) were investigated, using three types of zeolites (ZSM-5, HY, and zeolite-beta (BEA)) that differ in their silica/alumina ratios. Structural characterization of the catalysts was performed using ICP, XRD, BET, TEM, and NH3-TPD. Catalytic tests were carried out in a fixed-bed reaction system at 400 °C and 50 bar. In the hydrotreatment of soybean oil, higher conversions into liquid hydrocarbons and fuel-range hydrocarbons were found when supports with lower Si/Al2 ratios were used. Specifically, Pt/BEA (Si/Al2 = 25) produced the highest conversion into liquid products (72%) and the highest selectivity for hydrocarbons in the jet fuel (46%) and diesel (51%) fuels. A Pt loading amount of 3 wt% in this catalyst gave the best catalytic performance because of the optimal balance between acidic and metallic sites. Finally, the kinds of vegetable oils in the hydrotreatment performance over Pt/BEA (Si/Al2 = 25) affected the order; waste-cooking oil > jatropha oil > soybean oil.

Selective Production of p-Xylene from Dimethylfuran and Ethylene Over Tungstated Zirconia Catalysts.

p-Xylene (PX) is an important large-volume commodity chemical in the petrochemical industry. Therefore, research on producing PX from bio-mass-derived resources is a considerable interest in relation to future alternative technologies. Recently, a new potential route for the direct and selective production of bio-based PX was reported, referred to as the Diels-Alder cycloaddition of biomassderived 2,5-dimethylfuran (DMF) and ethylene followed by the dehydration of an intermediate. Here, we prepared tungstated zirconia (WOx-ZrO2) materials at different calcination temperatures and times as solid acid catalysts for PX production. From structural analyses and measurements of the surface acidity, the WOx-ZrO2 was found to be composed of mesopores with high surface acidity within the optimum calcination temperature and time range. This WOx-ZrO2 catalyst exhibited high catalytic activity upon the cycloaddition of DMF with ethylene as compared to commercial beta zeolite and previously reported silica-alumina catalysts.

Effect of Silica Content on Production of p-Xylene from Dimethylfuran/Ethylene Over Mesoporous SiO2­Al2O3 Catalysts.

Mesoporous SiO2­Al2O3 (SA) catalysts with different SiO2 contents were prepared, for the selective production of p-xylene from dimethylfuran/ethylene through the combination of cycloaddition and dehydrative aromatization reactions, by a co-precipitation method. For comparison, commercial SiO2­Al2O3 and ZSM-5 zeolites (Si/Al2 = 30, Si/Al2 = 80) were also employed as catalysts in the same reaction. The pore size of the catalysts played an important role in determining the catalytic performance in the production of p-xylene. Among the catalysts tested, the order of the yield and production rate of p-xylene was as follows: mesoporous SA > commercial SiO2­Al2O3 > commercial ZSM-5. In the mesoporous SA catalysts in particular, p-xylene yields showed a volcano-shaped trend with respect to the catalyst's SiO2 content. The SA-60 catalyst, with SiO2 = 52.3, showed the highest yield (75%) and production rate (57.7 mmol/g-cat · h) because of a catalyst structure with moderate pore size, which prevented side reactions.

Pilot study of effective methods for measuring and stretching for pectoral muscle tightness in breast cancer patients.

[Purpose] To evaluate differences in pectoral muscle tightness according to arm abduction angle and to determine the best arm abduction angle for stretching of pectoral muscle tightness in breast cancer patients. [Subjects and Methods] Horizontal abduction differences of shoulders were measured bilaterally by arm abduction to 45°, 90°, and 135° to determine the best arm abduction angle for measuring pectoral muscle tightness. Thirty-two patients were divided into three pectoral muscle stretching groups (A: 45°, B: 90°, and C: 135°). We measured the shoulder range of motion, scores of the Disabilities of the Arm, Shoulder, and Hand, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire and the Breast Module, and pain levels (using a visual analog scale) before and after therapy. [Results] The differences in degree of horizontal abduction between shoulders were significantly larger for arm abduction to 90° and 135° than that to 45°. Groups B and C showed greater improvements in horizontal abduction limitations than group A. [Conclusion] Horizontal abduction differences between shoulders are prominent when arms are abducted to 90° and 135°. The appropriate arm abduction angle for measuring horizontal abduction and effective stretching of pectoral muscle tightness may be >90°.

5,5'-substituted indirubin-3'-oxime derivatives as potent cyclin-dependent kinase inhibitors with anticancer activity.

To enhance the ability of indirubin derivatives to inhibit CDK2/cyclin E, a target of anticancer agents, we designed and synthesized a new series of indirubin-3'-oxime derivatives with combined substitutions at the 5 and 5' positions. A molecular docking study predicted the binding of derivatives with OH or halogen substitutions at the 5' position to the ATP binding site of CDK2, revealing the critical interactions that may explain the improved CDK2 inhibitory activity of these derivatives. Among the synthesized derivatives, the 5-nitro-5'-hydroxy analogue 3a and the 5-nitro-5'-fluoro analogue 5a displayed potent inhibitory activity against CDK2, with IC(50) values of 1.9 and 1.7 nM, respectively. These derivatives also showed antiproliferative activity against several human cancer cell lines, with IC(50) values of 0.2-3.3 microM. A representative analogue, 3a, showed greater than 500-fold selectivity for CDK relative to selected kinase panel and potent in vivo anticancer activity.

Mesoporous silica-pillared H(+)-kenyaite with highly ordered gallery structure.

Mesoporous silica-pillared H(+)-kenyaite (SPK) derivatives with highly ordered gallery structure and thermal resistance were prepared by the hydrolysis of TEOS (tetraethylorthosilicate) in interlayer space, using DDA (dodecylamine) as catalyst and template. DDA-TEOS/H(+)-kenyaite intercalation compounds were obtained by the dispersion of H(+)-kenyaite in DDA-TEOS solution. DDA-TEOS/H(+)-kenyaites were hydrolyzed rapidly in pure water, forming siloxane pillared H(+)-kenyaites. Calcination of siloxane pillared H(+)-kenyaites for 5 h at 600 degrees C in air resulted in mesoporous SPK derivatives. These exhibited refractions corresponding to a basal spacing of 5.0-5.5 nm, a uniform pore size of 2.5-3.0 nm and large surface areas between 707 and 877 m2/g. TEM images confirmed that SPK had uniform interlayer spaces of 2.0-3.0 nm in agreement with the gallery height and pore size data. The structure and physical properties of SPK remained stable after heating for 5 h at 800 degrees C in air. This is attributed to the stable structure of kenyaite composed of 4-fold SiO4 tetrahedral sheets, and the formation of firm silica pillars.