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A micromechanics analysis is performed for the determination of the five independent elastic moduli of unidirectional fiber composites. By considering viscoelastic phases and by using the correspondence principle and the inversion of the Laplace transform, the five time-dependent functions which characterize the effective behavior of viscoelastic composites are established. The predicted time-dependent behavior is applied for the analysis of viscoelastic laminated plates. The resulting viscoelastic effects are shown, and comparison between the results obtained within the classical laminated plate theory and the first-order shear deformation theory is discussed. 相似文献
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Jacob Hooker David Hinks Gerardo Montero Christopher Conlee 《Coloration Technology》2002,118(6):273-276
The synthesis of azo dyes via a conventional aqueous-based diazotisation and coupling reaction requires the use of relatively high concentrations of mineral acids, which leads to high electrolyte concentrations in wastewater. Reported in this paper is an environmentally benign one-pot method for the synthesis of a nonionic azo dye, N,N -diethyl- N -{4-[( E )-(4-nitrophenyl)diazenyl]phenyl}amine, in supercritical carbon dioxide without using a mineral acid. The product yield increased significantly with temperature, with 91% theoretical yield afforded at 80 °C. The pressure of the system had little influence on product yield. 相似文献
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Gibbs energies of formation of CoF2 and MnF2 have been measured in the temperature range from 700 to 1100 K using Al2O3-dispersed CaF2 solid electrolyte and Ni+NiF2 as the reference electrode. The dispersed solid electrolyte has higher conductivity than pure CaF2 thus permitting accurate measurements at lower temperatures. However, to prevent reaction between Al2O3 in the solid electrolyte and NiF2 (or CoF2) at the electrode, the dispersed solid electrolyte was coated with pure CaF2, thus creating a composite structure. The free energies of formation of CoF2 and MnF2 are (± 1700) J mol−1; {fx37-1} The third law analysis gives the enthalpy of formation of solid CoF2 as ΔH° (298·15 K) = −672·69 (± 0·1) kJ mol−1, which compares with a value of −671·5 (± 4) kJ mol−1 given in Janaf tables. For solid MnF2, ΔH°(298·15 K) = − 854·97 (± 0·13) kJ mol−1, which is significantly different from a value of −803·3 kJ mol−1 given in the compilation by Barinet al. 相似文献
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P Rougier B Paillot A LaPlanche F Morvan JF Seitz C Rekacewicz P Laplaige J Jacob S Grandjouan JM Tigaud MC Fabri M Luboinski M Ducreux 《Canadian Metallurgical Quarterly》1997,33(11):1789-1793
The aim of this Phase III, balanced randomised trial was to compare continuous intravenous infusion (CVI) of 5-FU with bolus (B) administration for metastatic colorectal cancer (CRC). One hundred and fifty-five non-pretreated patients were randomised to receive CVI 5-FU at a dose of 750 mg/m2/day (d), 7 d every 21 d (n = 77), or bolus 5-FU 500 mg/m2/d x 5 d every 28 d (n = 78). Incremental dose escalation at 50 mg per step was recommended in the absence of toxicity. All the patients had measurable metastatic disease (M), particularly, liver and a good performance status (WHO grade 0-1). Dose intensity was significantly higher in CVI than in the bolus group: 1369 mg/m2/week versus 558 mg/m2/week (P = 0.0001). Grade II-IV stomatitis was more frequent in the CVI group (31% versus 9%; P < 0.0001) as was hand and foot syndrome (14% versus 3%; P < 0.001). Diarrhoea (22% versus 12%) and grade III granulocytopenia (2% versus 6%) were comparable. Responses were more frequent in the CVI (26%) than in the bolus group (13%) (P < 0.04); progression-free survival was higher for the CVI group (P = 0.04), but there was no statistical difference in overall survival (median: 10 months (m) compared to 9 m), and 1 year survival (SD) 42% (6%) versus 40% (6%). In the multivariate analysis, survival was better for patients with a good PS, well-differentiated adenocarcinomas and a primary tumour without serosal extension. In conclusion, with a higher dose intensity, CVI 5-FU improved tumour control, but not overall survival. 相似文献
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F F?ndrich AM Waaga J Schr?der E Schweizer A Schmid S Jacob HH Wacker P Schroeder 《Canadian Metallurgical Quarterly》1995,27(2):1553-1554