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41.
42.
V. Hebert C. His J. Guille S. Vilminot T. L. Wen 《Journal of Materials Science》1991,26(19):5184-5188
8 mol% Y2O3-stabilized ZrO2 has been prepared by four routes which involve yttrium and zirconium metal organic compounds as starting materials. The thermal decomposition of the precursors has been investigated by means of thermal analysis, X-ray diffraction and SEM technique with regard to their chemical homogeneity and phase composition. The possible reactions during precursor preparations are discussed. 相似文献
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This paper describes the metadata and metadata management algorithms necessary to handle the concurrent execution of multiple tasks from a single workflow, in a collaborative service oriented architecture environment. Metadata requirements are imposed by the distributed workflow that calculates thermoelastic properties of materials at high pressures and temperatures. The scientific relevance of this workflow is also discussed. We explain the basic metaphor, the receipt, underlying the metadata management. We show the actual java representation of the receipt, and explain how it is converted to XML in order to be transferred between servers, and stored in a database. We also discuss how the collaborative aspect of user activity on running workflows could potentially lead to race conditions, how this affects requirements on metadata, and how these race conditions are precluded. Finally we describe an additional metadata structure, complementary to the receipts, that contains general information about the workflow. 相似文献
45.
Rodrigo S. da Silveira Andréa M. de Oliveira Sibele B. C. Pergher Victor Teixeira da Silva Ione M. Baibich 《Catalysis Letters》2009,129(3-4):259-265
Palladium and/or molybdenum catalysts supported on mordenite were prepared and characterized by XRD, UV–vis, DRS, textural properties analysis, TPR, TPD and chemical analysis. The Mo-catalyst rapidly deactivated after the first minutes reaction. The Pd-catalysts were active in the NO decomposition reactions. The incorporation of Mo in the Pd-catalysts improved their catalytic properties. 相似文献
46.
Fernanda de Carvalho Panzeri Pires‐de‐Souza Renata Espíndola Silveira Gabriel Abuna Michelle Alexandra Chinelatti Carla Cecilia Alandia‐Román Mario Alexandre Coelho Sinhoreti 《Microscopy research and technique》2015,78(12):1062-1068
The purpose of this study was to analyze, by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM), the morphology of sealant/enamel interface after surface treatment with Biosilicate. Before pits and fissures sealing, the occlusal surfaces of 10 sound human molars were sectioned perpendicularly at the fissures in order to obtain three slices for each tooth. Slices were randomly assigned into three groups (n = 10) according to sealing protocol: Group 1‐ Acid etching + Biosilicate + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 2‐ Acid etching + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 3‐ No sealing. All slices were subjected to thermal cycling (5,000 cycles; 5–55°C; dwell time: 30s). Half of the slices from each group (n = 5) were analyzed by CLSM and the other half by SEM. Groups 1 and 2 were also submitted to EDS analysis and their data were evaluated by Two‐Way ANOVA e Tukey's test (α=5%). EDS data analysis showed higher amounts of silicon (Si) ions than calcium (Ca) ions in Group 1 (P < 0.05); Group 2 presented higher amounts (P < 0.05) of Ca ions than Si ions. It may be concluded that the use of Biosilicate for surface treatment did not affect the morphology of glass ionomer‐based sealant/enamel interfaces. Microsc. Res. Tech. 78:1062–1068, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
47.
A molecular absorption method is proposed for the determination of phosphorus in biodiesel. The samples are mineralized using an ashing procedure at 550 °C followed by dissolution of the residue. The analytical procedure is based on the formation of a blue molybdenum complex. 1-amino-2-naphthol-4-sulfonic acid is used as reducing agent. The method was applied to biodiesel samples prepared from soy, canola and sunflower oils and from bovine fat. The limit of detection is 0.57 mg P kg−1 and the limit of quantification is 1.7 mg P kg−1. The observed mean relative standard deviation is about 5%. The simplicity of the procedure added to its precision, accuracy and low cost suggest that it is an excellent option for the determination of phosphorus in biodiesel. 相似文献
48.
Dr. Ana Maria ds Silveira 《Drying Technology》2013,31(9):1024-1025
49.
The performance of an adsorption icemaker prototype operating in a double-stage mass recovery cycle was experimentally investigated under the generation temperature of 75°C. The prototype was heated in the regeneration phase by an electric heater, and an analytical model was employed to assess the daily number of cycles and the ice production, if evacuated tube solar collectors were used to supply the regeneration heat. It was found that the parasitic heat consumed by the metallic part of the reactor greatly reduced the coefficient of performance (COP) and ice production per unit area of solar collector. A reduction of the parasitic heat by 60% would increase the COP in 54%, and the daily ice production per unit area of solar collector in 50 to 54%, depending on the insolation. The performance of the studied prototype was inferior to the performance of some prototypes presented in the literature, which were directly heated by solar energy and used methanol as refrigerant, but this type of prototype could be an alternative to avoid subatmospheric working pressures and to provide ice on rainy and low insolation days, if waste heat or another heat source is available. 相似文献
50.
Giana da Silveira Lima Fabrício Aulo Ogliari Manuela Gonçalves Souza e Silva Eliseu Aldrighi Münchow Cesar Liberato Petzhold Evandro Piva 《应用聚合物科学杂志》2013,127(5):4160-4167
This study evaluated the effectiveness of benzodioxole derivatives as coinitiators of radical polymerization in a model‐dental adhesive resin. To compose the adhesive resin, a monomer mixture based on 50 wt % of Bis‐GMA, 25 wt % of TEGDMA, and 25 wt % of HEMA was used. Camphorquinone (CQ) 1 mol % was used as a photoinitiator to initiate polymerization. 1,3‐Benzodioxole (BDO) and piperonyl alcohol (PA) were used as coinitiators at 0.25, 0.5, 1, 2, 4, 8, and 16 mol % level. In addition, tertiary amine, ethyl 4‐dimethylamino benzoate (EDAB) was used as coinitiator in the control group. Some physical, chemical, and mechanical properties of the polymer formed in the experimental adhesives were evaluated using the kinetics of polymerization, sorption and solubility, flexural strength, and elastic modulus tests. The results indicated that BDO and PA were effective coinitiators in the photoinitiator system based on CQ. Comparisons between the benzodioxoles derivative coinitiators and EDAB showed similar performance in the kinetics of polymerization and flexural strength. For water sorption and solubility evaluation, BDO and PA demonstrated significantly more sorption of water and less solubility than the EDAB control group. The findings suggest that BDO and PA were feasible alternatives to conventional amine as coinitiator. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献