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Two lignite samples, Beulah No. 3 and Big Brown No. 1, were liquefied at 420 °C using H2 and synthesis gas to determine the optimum beneficial amount of H2S in the batch autoclave reactor. Under the conditions employed, 50–100 psi partial pressure of H2S, nominally 4–10 wt% of daf lignite, was optimum for both samples. Synthesis gas outperformed H2 with and without H2S for the liquefaction of the two coals. 相似文献
105.
Solidification after extrusion of coaxial cables has been experimentally simulated. Solidification tests were performed with two HDPE grades and under several pressures; the extrusion velocity was varied in a suitable range so as to detect the critical velocity for void formation. A qualitative analysis of the void formation mechanism is carried out, and the predicted trends favorably compare with the critical velocity data. 相似文献
106.
G. BEN ABDERRAZIK F. MILLOT G. MOULIN A. M. HUNTZ 《Journal of the American Ceramic Society》1985,68(6):302-306
To determine the transport properties of oxide scales growing on an alloy, a laboratory apparatus was developed which allows plotting of characteristic V = f (i) curves and oxidation with an applied electric field. The apparatus and formalism used are described; it appears that such experimental procedures allow determination of the mean ionic transport number, ti; the conductivity values σ, σi , and σ,e ; and the effective charge, Z*, of the moving species in the oxide scale (A12 O3 in the present case). 相似文献
107.
Stress in Leached Phase-Separated Glass 总被引:2,自引:0,他引:2
When a phase-separated glass is leached, stresses develop because of release of thermal stresses, creation of surface area, ion exchange, and hydration. Analyses are presented for the thermal stresses, including the portion that develops on cooling from the heat-treatment temperature to the setting temperature of the less viscous phase. During leaching, the interfacial energy of the residual phase increases, so that phase tends to contract. A more important effect is the contraction caused by removal of alkali and B2 O3 from the residual phase during leaching. The extent of removal of B2 O2 decreases with heat-treatment time, tH , because the scale of the microstructure increases as t1/3 H . The change in residual B2 O2 content with tH is shown to be consistent with diffusion-controlled ion exchange. The dependence of stress on tH in partially leached glasses, measured by Drexhage and Gupta, results principally from the change in extent of ion exchange; the reduction in surface area with increasing tH also has a significant effect on the stresses. 相似文献
108.
A. J. Hugo D. M. Jakelski G. Stanitsas G. R. Sullivan R. R. Hudgins P. L. Silveston 《加拿大化工杂志》1986,64(2):349-351
In the approach to a cycle-invariant state in the forced feed concentration cycling of the CO oxidation over a NiO catalyst, a very long transient has been observed lasting 80 ks or more. This transient appears to be associated only with CO pretreatment of the catalyst and is not a general phenomenon. The slow convergence to the cycle-invariant state reported in certain modelling calculations in the literature appears to have a different cause. 相似文献
109.
The comfort diagrams and the so-called PMV-PPD values are already used today directly and indirectly in a wide field in technical practice, even at a standard level. This theory is known also in Hungary, and the PMV-PPD values have been used by us for the solution of a design problem. The task was to elaborate a calculation method, an index number suitable for the determination of the thermal confort effect in the case of occasional underheating of residential and communal buildings in winter.The results of this work are presented in this paper. 相似文献
110.
O Baeder-Bederski M Dürr M Borneff-Lipp P Kuschk R Netter G Daeschlein P Mosig R A Müller 《Water science and technology》2005,51(9):205-212
Different types of constructed wetlands in a pilot-plant system were fed with identical municipal waste water to compare the sanitisation process in two-stage systems. With combinations of a vertical and a horizontal flow filter an E. coli reduction of 5 log10 with an E. coli influent concentration of 10(7) MPN/100 ml was achieved. Using different filter materials in each stage the total performance of the two-stage system was independent from the sequence of these materials. However, using coarser filter material in the first stage makes the filter less prone to clogging and is thus the preferential option with regard to operational reliability. 相似文献