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Abstract: Using the grey relational analysis theory, this exploratory study was to find the principal factors of Quality of Service of Web Sevice and its contributions. The paper utilized a real Quality of Web Service data sets:QWS Dataset (1.0) to grey relational analysis. The results indicate: (1) the sequence of influencing factors of Web Service selection is Best Practices, Compliance, Availability, Successability, Reliability, Latency, Response Time, Throughput, Documentation; (2) nine factors can be classified into four kinds: the first important factors are Best Practices, Compliance, and Availability; the second important factors are Successability, Reliability; the third important kind factors are Latency, Response Time; the less important factors are Throughput, Documentation; (3) the percent contributions of four kinds factors to the QoS of Web Service is 36.68%, 22.96%, 20.6%, 19.77%. [Copyright &y& Elsevier]

Mesoporous Cu 2 O particles with different morphologies were synthesized via simple one-pot reactions. Effects of reducing agents, dispersant, template, and temperature on the structure of the prepared materials were investigated. Mesoporous flower-shaped Cu 2 O materials were obtained at 70 ℃ using glucose as a reductant . Different hollow microsphere shapes of Cu 2 O could be prepared at 40 ℃ using another type of reductant, ascorbic acid . The results indicated that the uniform morphology of synthesized Cu 2 O with mesopores presented a maximum specific surface area of 45.3 m 2 /g. Furthermore, the as-prepared Cu 2 O particles showed good photodegradation efficiencies of methyl orange in the range of 86.0–93.7%, depending on their morphologies. [ABSTRACT FROM AUTHOR]

Abstract: The separation of a hydrogen isotope mixture on porous materials was studied using equilibrium and breakthrough experiments. The adsorption equilibria of H2 and D2 on SBA-15 with mesopores and molecular sieves 5A, Y, and 10X with micropores were measured at 77 K using the volumetric method. The breakthrough experiments of a H2 and D2 mixture in each adsorbent bed were carried out at various conditions of flow rate and pressure. The equilibrium ratio of D2 to H2 on mesoporous molecular sieves was larger than the ratio on microporous molecular sieves (SBA-15 > 10X > Y > 5A), but the difference among the adsorbents decreased with increases in pressure. On the other hand, the order of breakthrough separation factor showed the opposite result (SBA-15 < 10X < Y < 5A). The breakthrough separation factors for zeolite 10X was approximately equal to the equilibrium ratio of D2 to H2 at the corresponding partial pressures, whereas zeolites 5A and Y showed higher breakthrough separation factors than their equilibrium ratios. In SBA-15, the separation factors from breakthrough results were even smaller than the corresponding equilibrium ratio. In the microporous adsorbent with a limited pore size (zeolite 5A in the study), the diffusion mechanism contributed to the separation of hydrogen isotope gases as one of key factors. [Copyright &y& Elsevier]

Abstract: The synthesis and characterization of thermoresponsive hydrogels on the basis of N-isoproplyarylamide (NIPAAm) and acrylamide (AAm) copolymers crosslinked with a novel biodegradable crosslinker (PEG-co-PLA) were carried out in this study. Swelling measurement results demonstrated that four gels of PNAM5, PNAM10, PNAM12 and PNAM15 are thermoresponsive. The equilibrium swelling ratio and degradation of the hydrogels strongly depend on hydrogels composition. The morphology of the hydrogels was observed by scanning electron microscopy (SEM), and their thermal property was characterized by differential scanning calorimetry (DSC). The results show that the proportion of AAm in the copolymer has notable effect on the low critical solution temperature (LCST) of the hydrogel. When the molar ratio of AAm to NIPAAm was increased from 1:10 to 3:10 the LCST of the copolymer increased from 39.7 to 64.2°C. The compression modulus of PNAM15 is of the highest among other hydrogels, because PNAM15 hydrogel has a more compact structure. [Copyright &y& Elsevier]

Abstract: A novel thermosensitive and hydrogel was designed and synthesized by graft copolymerization of N-isopropylacrylamide (NIPAAm) with biodegradable carboxymethylchitosan (CMCS). The influence of the content of CMCS grafted on the properties of the resulted hydrogels was examined. The morphology of the hydrogels was observed by scanning electron microscopy (SEM), their thermal property was characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and deswelling/swelling kinetics upon external temperature changes. In comparison with the conventional PNIPAAm hydrogels, the resulted hydrogels have improved thermosensitive properties, including enlarged water content at room temperature and faster deswelling/swelling rate upon heating. The strategy described here presents a potential alternative to the traditional synthesis techniques for thermosensitive hydrogels. [Copyright &y& Elsevier]