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101.
The Thermodynamic Properties of Silicon Oxynitride 总被引:1,自引:0,他引:1
A critical assessment of thermal and equilibrium data for silicon oxynitride (Si2 N2 O) is presented. Selected values for the heat of formation of Si2 N2 O from the elements and the absolute entropy of Si2 N2 O at 298.15 K are ΔH0 f,298 =−947.7 ± 5.4 kJ/mol and S0 298 = 45.35 ± 0.4 J/mol·K, respectively. A table of thermodynamic functions for Si2 N2 Ofrom 298 to 2500 K, which has been calculated from the analysis of the literature data, is also presented. 相似文献
102.
The provision of a downcomer to classical turbulent bed Contactor (TBC) increases the gas treating capacity of the equipment. When the downcomer is provided, it is expected that all the liquid passes through the downcomer only without any liquid flow through the distributor. In the present study, the operational regime for the flow of liquid only through the downcomer is experimentally evaluated for various geometric parameters and particle characteristics. It is observed that the preferred operational regime without dumping and weeping increases with an increase in Archimedes number and downcomer diameter, and decreases with an increase in static bed height and downcomer weir height. Correlations are proposed to satisfactorily predict experimentally observed operational regime. 相似文献
103.
Carsten Dachsbacher Jaroslav Křivánek Miloš Hašan Adam Arbree Bruce Walter Jan Novák 《Computer Graphics Forum》2014,33(1):88-104
Recent years have seen increasing attention and significant progress in many‐light rendering, a class of methods for efficient computation of global illumination. The many‐light formulation offers a unified mathematical framework for the problem reducing the full lighting transport simulation to the calculation of the direct illumination from many virtual light sources. These methods are unrivaled in their scalability: they are able to produce plausible images in a fraction of a second but also converge to the full solution over time. In this state‐of‐the‐art report, we give an easy‐to‐follow, introductory tutorial of the many‐light theory; provide a comprehensive, unified survey of the topic with a comparison of the main algorithms; discuss limitations regarding materials and light transport phenomena and present a vision to motivate and guide future research. We will cover both the fundamental concepts as well as improvements, extensions and applications of many‐light rendering. 相似文献
104.
Roland Schmidt Ulrich Hammon Stefan Gottfried M. Bruce Welch Helmut G. Alt 《应用聚合物科学杂志》2003,88(2):476-482
The synthesis of iron(II) complexes with various tridentate di(imino)pyridine ligands and their potential as ethene oligomerization catalysts are described. The ligands are characterized by 1H‐ and 13C‐NMR spectroscopy and the complexes only by mass spectrometry due to their paramagnetism. After activation either with methylalumoxane (MAO) or with a heterogeneous cocatalyst consisting of partially hydrolyzed trimethylaluminum and silica gel, the prepared complexes proved to be good catalysts for the oligomerization of ethene. 1‐Octene, 1‐hexene, and 1‐decene were the major products, formed in very high isomeric purity (99.9 %). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 476–482, 2003 相似文献
105.
The degradation kinetics of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate), a member of the Nodax family of polymers, were investigated using transient constant shear rate and dynamic time sweep rheological tests. The rate of chain scission at several times and temperatures was correlated with viscosity data and verified using molecular weight determination of the degraded samples. The experimental results show that the molecular weight and the viscosity of Nodax decrease with time over the range of temperatures that were studied (155–175°C). The degradation kinetics, which exhibited first‐order behavior, were determined as a function of the flow history and thermal history. An apparent activation energy of 189 ± 5 kJ/mol for thermal degradation was found by modeling variations in the rate with temperature using an Arrhenius law model. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 66–74, 2005 相似文献
106.
S. SIMARD M. DROGOWSKA H. ME´NARD L. BROSSARD 《Journal of Applied Electrochemistry》1997,27(3):317-324
The electrochemical behaviour of 1024 mild steel electrodes is investigated in the presence of 0.05–0.5 M sodium bicarbonate in aqueous solution at pH 8.9 and 25°C. Voltammograms are obtained with a rotating gold ring-mild steel electrode and the effect of the NaHCO3 concentration, the potential limits and the rotation speed of the disc electrode is considered. The voltammograms display an oxidation peak current at low potentials, a passivity region and a transpassive region at high potentials for the potential sweep in the anodic direction. The oxidation current in the passivity region is practically independent of the applied potential and the NaHCO3 concentration. The rate-determining step of the oxidation reaction in both the oxidation peak current region and the transpassive region is determined. 相似文献
107.
Garrett BC Dixon DA Camaioni DM Chipman DM Johnson MA Jonah CD Kimmel GA Miller JH Rescigno TN Rossky PJ Xantheas SS Colson SD Laufer AH Ray D Barbara PF Bartels DM Becker KH Bowen KH Bradforth SE Carmichael I Coe JV Corrales LR Cowin JP Dupuis M Eisenthal KB Franz JA Gutowski MS Jordan KD Kay BD Laverne JA Lymar SV Madey TE McCurdy CW Meisel D Mukamel S Nilsson AR Orlando TM Petrik NG Pimblott SM Rustad JR Schenter GK Singer SJ Tokmakoff A Wang LS Wettig C Zwier TS 《Chemical reviews》2005,105(1):355-390
108.
109.
Bong-Kyu Chang Yong Lu Hongyun Yang Bruce J. Tatarchuk 《Journal of Materials Engineering and Performance》2006,15(4):439-441
In this study, a microfibrous carrier consisting of 3 vol.% of 8 μm (diameter) glass fibers is used to entrap 45 vol.% of
150 to 250 μm (diameter) SiO2 support particulates. ZnO is then nanodispersed onto the support by impregnation at the loading of 17 wt.%. At equivalent
bed volumes, ZnO/SiO2-entrapped materials provide twofold longer breakthrough times for H2S (with a 67% reduction in sorbent loading) compared with packed beds of 1 to 2 mm commercial extrudates. Five-log reductions
in H2S concentration with up to 75% ZnO utilization at breakthrough are achieved. H2S concentrations from 60 to 2000 parts per million in volume (ppmv) can be reduced to as little as 0.6 ppmv at 400°C in 30%
H2O at a face velocity of 1.7 cm/s for layers as thin as 1.0 mm. At 500 to 600°C, ZnO/SiO2-entrapped materials provide much higher regenerability in air than do 1 to 2 mm commercial extrudates. The use of glass fibers
permits greater than 50 regeneration cycles.
This paper was presented at the ASM Materials Solutions Conference & Show held October 18–21, 2004 in Columbus, OH. 相似文献
110.
We present the design, fabrication, and performance of the multi-specimen heated platform for linear in situ heating during the Temperature-Programmed XPS (TPXPS). The platform is versatile, compatible with high vacuum (HV) and bakeout. The heater platform is tested under in situ linear heating of typical high surface area sorbent∕catalyst support--nanoporous TiO(2). The platform allows the TPXPS of multiple samples located on specimen disk that can be transferred in and out of the TPXPS chamber. Electric characteristics, temperature and pressure curves are provided. Heating power supply, PID temperature controller, data-logging hardware and software are described. 相似文献