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Effect of expanded vermiculite (EVMt) and nano-zinc oxide on thermal-oxidative (pressurized aging vessel, in situ thermal aging) and ultraviolet (UV) aging was investigated. The results show that organic expanded vermiculite (OEVMt) modified bitumen forms an exfoliated nanostructure. The morphology of bitumen is significantly influenced by two nanomaterials according to atomic force microscopy. The influence of different nanomaterials on long-term aging resistance of bitumen depends on their structures and shielding function to UV radiation. Thermo-oxidative aging resistance of bitumen can be effectively improved with the introduction of OEVMt, while nano-zinc oxide has obvious improvements in UV aging resistance of bitumen. [ABSTRACT FROM AUTHOR]

The Rasch model can be used to transform ordinal data into interval data. Rasch has seldom been incorporated in data envelopment analysis (DEA) models. Therefore, this study attempts to apply the Rasch model in DEA to analyse the performance of seven districts including Taipei; Kaoshong; Taichung; Hwalian; Scenery; Taoyuan, Hsinchu, Miaoli; Others in Taiwan containing 56 international tourist hotels during 2009 using five criteria, including average occupancy rate, average room rate, average production value per employee in the accommodation department, average production value per employee in the catering department and operating income/expenses. Furthermore, this study also compared the results with and without the Rasch-bounded DEA model. As expected of the analytical results that applying the DEA model using the bounded formulas achieves better distinguishing power than applying the model without using the bounded formulas. Furthermore, the effectiveness value of each district of Taiwan (Taipei (1.000), Kaoshong (0.3661), Taichung (0.3494), Hwalian (0.2658), Scenery (0.6476), Tyoyuan, Hsinchu, Miaoli (0.5623), others (0.3127)) during 2009 is obtained. [ABSTRACT FROM AUTHOR]

Cs2.5H0.5PW12O40 supported on palygorskite (CsHPW/Pa) were synthesized and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy. CsHPW inside CsHPW/Pa was retained intact Keggin anion and highly and uniformly supported on the fiber of Pa, which performed stable catalytic activity for esterification of oleic acid with ethanol. Under optimum conditions, the following amounts were reached: 20%CsHPW/Pa catalyst, 80°C, 8 h, molar ratio (ethanol to oleic acid) 10:1, catalyst amount 8 wt% (in relation to the oleic acid mass), removal water agents amount 50 g/mol (basis on the oleic acid molar), and the conversion of oleic acid reached 73%. [ABSTRACT FROM PUBLISHER]

Esterification of oleic acid with methanol was investigated using tungstophosphoric acid (H3PW12O40) immobilized on the 3-aminopropyltriethoxysilane (H2N(CH2)3Si(OC2H5)3) functionalized palygorskite. Among different loading catalysts, 15% (w/w) H3PW12O40 immobilized onto functionalized palygorskite showed stable and substantially high activity with about 90% oleic acid conversion. Immobilized catalysts were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, and temperature programmed desorption of NH3 for their surface element compositions and chemical states, crystallization, and acid strength, respectively. Characterization results indicated that H3PW12O40 was chemically and uniformly dispersed on modified palygorskite. [ABSTRACT FROM PUBLISHER]

We investigated in total 80 wine samples of different types and seven grape juice and 23 beer samples purchased from markets in Central Europe in order to understand the arsenic (As) speciation and help assess the potential As toxicity via intake of alcoholic beverages. Generally, total As concentrations in most samples investigated were below the drinking water limit 10 µg l−1 published by the World Health Organization (WHO); ranging from 0.46 to 21.0 µg l−1 As in red and white wines and from 0.75 to 13.4 µg l−1 As in beers. In addition, concentrations of total As in rice wine and in rice beer were 0.63–6.07 and 3.69–8.23 µg l−1 As, respectively. The total As concentrations in ice wine ranged from 7.94 to 18.8 µg l−1 As, significantly higher than in white and red wine. Arsenite predominated as the As species in most of the wine samples, whereas arsenate was the dominant species in rice wine, beer and rice beer. Methyl As components were usually minor components in all wine and beer samples. Monomethylarsonic acid, dimethylarsinic acid and two additional unknown As species were frequently found in grape juice, late harvest and ice wine with higher sweetness. After air exposure, arsenite, arsenate, monomethylarsonic acid and dimethylarsinic acid were stable at 4°C for months, probably due to the acidic conditions of wine and beer samples. The presence of sulfite had little influence on As speciation in wine. Despite the predominance of more toxic arsenite and arsenate in wine and beer, the estimated weekly exposure to As (via consumption of beer, wine and rice wine) is low. The As intake per capita is 6.81 µg from beer, <1.93 µg from wine and 0.88 µg from rice wine, estimated using the median of total As concentration multiplied by the average consumption per capita of the corresponding beverage. [ABSTRACT FROM AUTHOR]

Heavy nitrogen doping of TiO2 thin films has been achieved by ion-beam-assisted deposition. The heavily doped films have a distorted anatase crystal structure and show an increase in visible-light absorption compared to films with only light nitrogen doping. The enhanced absorption is shown by a first-principles density-functional calculation to result from an electronic band-gap narrowing, in contrast to the appearance of isolated N 2p states above the valence-band maximum that occur with light nitrogen doping. [ABSTRACT FROM AUTHOR]

This paper describes the design, implementation and evaluation of Mykil, a new key management system for supporting secure group multicast. Mykil was developed on a combination of group-based hierarchy and key-based hierarchy systems for secure group key management. The advantages of Mykil include a fast and efficient rekeying operation for large group sizes, continuous availability of the key management service in a disconnected network environment, an ability to map group structure to the underlying network infrastructure, and support for user mobility and smaller, handheld devices. A prototype of Mykil has been implemented. The paper describes this implementation and reports on the performance measured. [ABSTRACT FROM AUTHOR]