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81.
A needle penetrometry was performed loading steady force in a range from 1×10−3 to 2 N to pelletized coal upon heating via a cylindrical needle. From the observed effects of shear rate on apparent viscosity of softening coal pellet, defined as the shear-rate to shear-stress ratio, it was found that the pellet behaved as a Newtonian fluid for shear rates lower than a critical one while as a pseudo-plastic fluid for higher shear rates. The penetrometry was also carried out varying the force with time. The variable force loading enabled to maintain the shear rate well below the critical one, and thereby to measure the apparent viscosity of coal pellets as Newtonian fluids over a temperature range from 600 to 800 K. Upon heating at 10 K min−1, the apparent viscosity of Goonyella coal pellet decreased from about 1010 Pa s at 640 K down to a minimum of about 104 Pa s at 755 K, and increased up to 109 Pa s at 800 K. In a course of heating as above, the viscosity of Blind Canyon coal pellet decreased above 600 K, underwent a minimum of about 106 Pa s at 715 K, and increased up to 1010 Pa s at 770 K. Decreasing the heating rate from 10 to 3 K min−1 caused the minimum viscosities of the pellets to increase by 1-2 orders of magnitude. 相似文献
82.
T. Tabata R. Ito Y. Itikawa N. Itoh K. Morita 《Atomic Data and Nuclear Data Tables》1983,28(3):493-530
Experimental data on the number-backscattering coefficient RN, the energy-backscattering coefficient RE, and the mean fractional energy rE of backscattered particles are tabulated for H, D, and He ions normally incident on elemental solids. References through 1981 are covered. The dependence of RN and RE on incident energy is shown graphically for energies from about 10 eV to 100 keV by plotting the experimental data and the empirical formulas of Tabata et al. Graphs are provided for 36 elemental targets of atomic numbers from 6 to 92. 相似文献
83.
84.
85.
Masahiro Tabata Yoshikazu Nishida Tatsuya Kodama Keisuke Mimori Takashi Yoshida Yutaka Tamaura 《Journal of Materials Science》1993,28(4):971-974
An oxygen-deficient Mn(II) ferrite (Mn0.97Fe2.02O3.92) was synthesized and its reactivity to reduce CO2 gas into carbon was studied at 300°C. The oxygen-deficient Mn(II) ferrite was obtained by flowing H2 gas through Mn(II) ferrite with a nearly stoichiometric composition of Mn0.97Fe2.02O4.00 at 300° C. The lattice constant of the oxygen-deficient Mn(II) ferrite (0.8505nm) is larger than that of the Mn(II) ferrite with a nearly stoichiometric composition (0.8498nm). The chemical composition of the Mn(II) ferrite changed from Mn0.97Fe2.02O4.00 to Mn0.97Fe2.02O3.92 during the H2 reduction process, indicating that the oxygen is deficient in the spinel structure of the Mn(II) ferrite. This was confirmed by Mössbauer spectroscopy and X-ray diffractometry. The efficiency of CO2 decomposition into carbon at 300°C with the oxygen-deficient Mn(II) ferrite was much lower by about 105 than that of oxygen-deficient magnetite. This is considered to be due to the difference in electron conductivity between Mn(II) ferrite and magnetite, which determines the reductivity for CO2 into carbon by donation of an electron at the adsorption site. 相似文献
86.
The rates of desorption of carbon dioxide from supersaturated water solutions into pure carbon dioxide or nitrogen gas stream were measured at 15,25, and 35°C in a baffled agitated vessel with a flat gas-liquid interface operated in a continuous manner. The volumetric liquid-phase mass transfer coefficients for the bubbles generated in the agitated liquid and the enhancement factors of the volumetric liquid-phase mass transfer coefficient for the free liquid surface due to the bubbling were calculated from the measured desorption rates and correlated as functions of the relative supersaturation of the solution and the liquid-phase Reynolds number. 相似文献
87.
88.
Haruo Yoshimura Yoshihisa Endo Shigeru Hashimoto 《Journal of the American Oil Chemists' Society》1991,68(8):623-628
Terminal olefins can be converted into the corresponding sulfonates by sulfonation with SO3 followed by hydrolysis, the products are used as detergent ingredients. Although internal olefins were also expected to be
good feed stocks, it was difficult to convert them into the corresponding sulfonates with as good of a yield as that of terminal
olefins under the same synthesis conditions.
Our studies have been carried out in order to clarify the reason for poorer conversion of the internal olefins. It was found
by a nuclear magnetic resonance spectroscopic study that the major components of the sulfonated intermediate of internal olefins
wereβ-sultones, the amounts of which were usually very small in sulfonated terminal olefins. A portion of theseβ-sultones was desulfonated, depending on temperature, to the original olefins and the corresponding sulfate salts during alkaline
hydrolysis. The prevention of desulfonation of theβ-sultones in the hydrolysis process was one of the most important aspects for the production of internal olefin sulfonates.
Finally, by keeping the hydrolysis temperature below 35°C, the conversion of internal olefins into sulfonates was achieved
with the same yield as that of conventional terminal olefins. 相似文献
89.
Generally, plastics and plastic films are low in moisture absorption and high in electric insulation. They are inherently easy to be charged with static and can cause a variety of static troubles. We developed a functional packaging material to solve these static problems, by using potassium ionomer. We reported good antistatic performance (e.g. short static decay time, and excellent ash test) of potassium ionomer films in a previous paper. However, a mechanism underlying the antistatic property of potassium ionomer has not yet been fully elucidated. In this study, we measured the space charge distributions of potassium ionomer using the pulsed electro‐acoustic method. As a result of the space charge measurements, we found characteristic charge distribution of potassium ionomer film. On the basis of the existence of this characteristic charge distribution, we speculate that the space electric charge distribution of a potassium ionomer film under a direct current electric field shows apparent electric charge movement. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
90.
Shigeki Shibayama Takeo Kakuta Nobuyoshi Miyazaki Haruo Yokota Kunio Murakami 《New Generation Computing》1984,2(2):131-155
This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation. 相似文献