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1.
Kinetic equations for initial sintering were obtained by combining the conventional kinetic equation with an empirical expression for grain growth in the initial stage. The equations describe the isothermal shrinkage of ZnO in O2 at 80 torr and 800° to 950°C. The equation also successfully analyzed the sintering of powder compacts of Al2O3 studied by other workers.  相似文献   
2.
使用振动球磨机将三水铝石粉体进行干式微粉碎.粉碎实验条件为介质球/试样(质量比)=8.5.研究调查了不同粉碎时间处理粉碎试样的机械力化学效应(平均粒径、结晶无定形和加热特性).结果表明,长时间粉碎,达到粉碎平衡,平均粒径趋于极限值.粉碎过程中未脱水.由于粉碎,加热脱水温度、结晶相变温度降低.  相似文献   
3.
This paper presents a novel type of flux‐modulating synchronous machine (FMSM) in which permanent magnets (PMs) are embedded in the stator back‐iron. The rotor has neither windings nor PMs. A prototype machine with an outer‐rotor configuration was designed and manufactured to validate the operating principle of the FMSM. The characteristics in the motor mode of the prototype machine were also investigated with a vector control system. The results of the investigations show that, as in surface‐mounted PM motors, the torque of the FMSM is predominantly generated by the PM flux and can be controlled using the armature current.  相似文献   
4.
Cooked rice and commercial glutinous rice cakes were frozen by a capsule-packed freezing method we developed, then stored. Characteristics of samples frozen by this new method were compared with those of samples frozen in deep freezers (–20°C and –50°C), or chilled in an ordinary (5°C) or Cold Fog refrigerator (0°C). Texturometer measurements, glucoamylase digestion, and X-ray diffraction analysis of specimens thawed to room temperature indicated that the samples prepared by our new method were superior to those frozen in conventional freezers or chilled in refrigerators. Simulation experiments in a program freezer showed that rapid freezing and adequate tempering were characteristic of our capsule-packed method.  相似文献   
5.
Information filtering is an intelligent function that selects the relevant messages and items of use or interest to the user from a large amount of incoming information. This function has become very important for the rapid development of network technology. This article focuses on information filtering for the management of emergency situations. We believe that special purpose-built "information filtering systems" should be developed to cope with the problem of information overload in emergency management. In this article, we first investigated features of information in emergent situations and then proposed an information filtering system for emergency management. The proposed system is composed of two parts: causal analysis and information classification. A prototype system has been developed and its effectiveness was evaluated by experiments.  相似文献   
6.
Hydration of CaAl2O4 (CA) was studied by calorimetry, analysis of the liquid phase, measurement of the combined water, and electron microscopy. During the induction period, the solution remains almost unchanged and is equilibrated temporarily with both superficially intrusion-hydrated CA particles and Al(OH)3 gel formed by dissociation of Al(OH)4 ions, the solubility of the Al(OH)3 gel being 10–4.24 molkg–1 at 25°C, while the intrusion-hydrated layer on the CA particles grows following a nearly linear law to reach a critical thickness (∼3 nm at 10° to 20°C, or 12 nm at 30°C). At this point destruction of the layer occurs, nuclei of hydrous compounds are generated, and the induction period terminates. Subsequent reaction proceeds in accordance with the rate equation of Schiller based on the dissolution-crystallization mechanism.  相似文献   
7.
Nowadays, it is quite easy to read or write kanji, that is Chinese character, by. writingthem on the computer monitor tube and/or word processor on screen. On the other hand, their realmeanings or history as they have originated and developed can not always be understood by theJapanese people.Moreover, any kanji today is often used only as a symbol without other meaning, andmeaningless words otherwise than their pronunciations are prevalent;which trend trend should never besupported by the public in general.In this study, we propose a system of educational tools for presenting kanji characters to let thestudents understand meanings of them as they originated from their prototypes or hieroglyphicimages representing their original meanings. The key frame or interval figure method is one ofeffective methods in computer graphic (CG) to show the transition of one original figure (A) to itscurrent form (B). Using this method is considered very effective when kanji is usually written ordisplayed in straight lines and curves. However, sometimes and kanji is also written or drawn like apicture with a special pen or a Japanese fude () to make adequate a main auxiliary techniquecalled morphing introduced in this study. Several examples in point are demonstrated on the videotape at the conference.  相似文献   
8.
A grid‐connected inverter is indispensable for photovoltaic power generation and smart grid systems, and it must be designed for stable operation. The impedance method based on the Nyquist criterion is often utilized to analyze the stability of grid‐connected inverter systems. The impedance method is based on the eigenvalues of the product of the inverter output admittance and the line impedance matrices in the frequency domain. However, the frequency characteristics have so far been derived only for inverters with analog control systems. A new frequency analysis method for inverters with digital control systems is proposed in this paper. First, a stability analysis example for a three‐phase LCL‐type inverter controlled digitally is shown and the results are compared and validated with those by simulation using a Saber simulator. Finally, they are also compared and validated with experimental results digitally controlled by a DSP‐based system.  相似文献   
9.
Trypsin was purified from the pyloric ceca of spotted mackerel (Scomber australasicus) by gel filtration on Sephacryl S‐200 and Sephadex G‐50. The purification and yield were 20‐fold and 81%, respectively, as compared to those in the starting crude extract. Final enzyme preparation was nearly homogeneous in sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) and the molecular weight of the enzyme was estimated to be 24,000 Da by SDS–PAGE. The trypsin was stable at pH 5–11 for 30 min at 30C, and its maximal activity against Nα‐p‐tosyl‐L‐arginine methyl ester was pH 8.0. Trypsin was heat‐stable up to about 50C for 15 min at pH 8.0. Optimum temperature of the trypsin enzyme was 60C. The enzyme was stabilized by calcium ion. The purified trypsin was strongly inhibited by serine protease inhibitors such as N‐p‐tosyl‐L‐lysine chloromethyl ketone and soybean trypsin inhibitor, suggesting that it is a trypsin‐like serine protease. N‐Terminal amino acid sequence of spotted mackerel trypsin was IVGGYECTAHSQPHQVSLNS.  相似文献   
10.
Several characteristic equations in intermediate sintering dependent on a grain-growth mechanism were quantitatively estimated using the microstructural data of sintered compacts. The relations which were calculated with a computer based on many assumptions described well the changes of a pore-size distribution, of an average radius of grains, and of a specific surface area of an easily sinterable alumina during the sintering. The reasonableness of these assumptions is discussed.  相似文献   
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