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31.
Hwack Joo Lee Hyun Ryu Hyun Min Park Jong Hoo Paik Sahn Nahm Jae-Dong Byun 《Journal of the American Ceramic Society》1998,81(6):1685-1688
Microstructural studies on the interfacial boundaries of 1:1 and 1:2 ordered domains in (Ba0.9 La0.1 )(Mg0.37 Nb0.63 )O3 were conducted using high-resolution transmission electron microscopy and X-ray diffractometry. Both 1:2 and 1:1 ordered domains coexisted in a fully ordered single grain. Each ordered domain occupied its own region, and the interfaces were atomically sharp and coherent. The wavelength of the superlattice modulation was ∼0.47 nm in the 1:1 ordered domain and ∼0.71 nm in the 1:2 ordered domain. The transition from the 1:2 ordered region to the 1:1 ordered region was clearly shown at the interface. These observations well support the structural models that have been previously presented. 相似文献
32.
33.
Shi Hyoung Ryu Hae Sung Lee Chong Nam Chu 《International Journal of Machine Tools and Manufacture》2003,43(14):2177
In this research, an effective method for the form error prediction in side wall machining with a flat end mill is suggested. The form error is predicted directly from the tool deflection without surface generation by cutting edge locus with time simulation. The developed model can predict the surface form error accurately about 300 times faster than the previous method. Cutting forces and tool deflection are calculated considering tool geometry, tool setting error and machine tool stiffness. The characteristics and the difference of generated surface shape in up milling and down milling are discussed. The usefulness of the presented method is verified from a set of experiments under various cutting conditions generally used in die and mold manufacturing. This study contributes to real time surface shape estimation and cutting process planning for the improvement of form accuracy. 相似文献
34.
The interrelationship between defect chemistry, non-stoichiometry, grain boundary transport and chemical stability of proton conducting perovskites (doped alkaline earth cerates and zirconates) has been investigated. Non-stoichiometry, defined as the deviation of the A : M molar ratio in AMO3 from 1 : 1, dramatically impacts conductivity, sinterability and chemical stability with respect to reaction with CO2. In particular, alkaline earth deficiency encourages dopant incorporation onto the A-atom site, rather than the intended M-atom site, reducing the concentration of oxygen vacancies. Transport along grain boundaries is, in general, less favorable than transport through the bulk, and thus only in fine-grained materials does microstructure impact the overall electrical properties. The chemical stability of high conductivity cerates is enhanced by the introduction of Zr. The conductivity of BaCe0.9–x
Zr
x
M0.1O3 perovskites monotonically decreases with increasing x (increasing Zr content), with the impact of Zr substitution increasing in the order M = Yb Gd Nd. Furthermore, the magnitude of the conductivity follows the same sequence for a given zirconium content. This result is interpreted in terms of dopant ion incorporation onto the divalent ion site. 相似文献
35.
Tae-Il Suh Eui-Jin Kim Bum-Jik Lee Jon-Ha Ryu Sung-Eun Lee 《International Journal of Control, Automation and Systems》2010,8(2):454-461
This article describes the performance comparison of several tracking filters from the viewpoint of gun fire control. It is common that filter performance can be represented by the RMSE of the current state. However, for the design of a gun fire control system, the performance of the tracking filter in terms of prediction is more important since the current state proceeds with a designed dynamic model to a certain future which is used for the final gun order. It is shown that the predicted results amplify the current state RMSE and can be a good measure. 相似文献
36.
K.?H.?Lee H.?S.?Ryu K.?C.?RheeEmail author 《Journal of the American Oil Chemists' Society》2003,80(1):85-90
Solubility characteristics of commerical soy protein products (flours, concentrates, and isolates) were determined under various
conditions. From the solubility profiles at various pH values and NaCl concentrations, soy protein isolates can be divided
into three groups. One group had high solubility near the pl. Another group had low solubility near the pl, but high solubility
at pH 11. The third group had low solubility even at pH 11. Except for the hydrolyzed products, the protein solubilities of
the soy protein products at various salt concentrations were very low. Temperature did not significantly affect the protein
solubility, although a few products showed more than a 20% increase at temperatures >50°C. Soy protein concentrates and soy
protein isolates showed similar solubility profiles. The proteins in all commercial products (except flours) tested were denatured,
as evident from the solubility profiles in the presence of salt and the enthalpy values from DSC. 相似文献
37.
M Vashishtha T Phalen MT Marquardt JS Ryu AC Ng M Kielian 《Canadian Metallurgical Quarterly》1998,140(1):91-99
Hypergastrinaemia-associated changes of non-antral argyrophil cells in man are of increasing interest, because of the development of potent inhibitors of gastric acid secretion. Using an antibody against chromogranin A, we identified micronodular endocrine cell hyperplasia of the oxyntic mucosa in gastric biopsy specimens of patients with hypergastrinaemia of different backgrounds. Consecutive ultrathin sections were examined at the electron-microscopical level. Endocrine cell types within the (extraepithelial) micronodules closely resembled those in the adjacent mucosa. Micronodules were classified into two groups. The first group was composed of endocrine cells only and predominated in patients with drug-induced hypergastrinaemia and/or chronic gastritis, and in a gastrinoma/MEN I patient. The second group represented "neuroendocrine complexes", showing a close intermingling of non-myelinated nerve fibres with endocrine cells, and was found predominantly in pernicious anaemia. Micronodular argyrophil cell growth in man is therefore heterogeneous and depends on the background of the hypergastrinaemia. 相似文献
38.
Wireless Personal Communications - Narrowband Internet of Things (NB-IoT) is a Quasi-5G technology that will provide coverage for massive number of low-power consumption applications. Hence, the... 相似文献
39.
Although prior studies have stressed the importance of technology in service innovation, debates on the roles of technology continue to surface. This study aims to investigate the role of technology in service innovation based on a service innovation framework. After identifying four innovation orientations, we propose three competing models having different roles of technology (direct, indirect, and moderating). Using data from 193 service firms, we determine which model best explains the role of technology. Results show that technology plays multiple roles in service innovation. Our study helps managers effectively coordinate their technology infusion into service innovation to improve firm performance. 相似文献
40.
This study is to investigate the factors influencing the alcohol production byKluyveromyces fragilis using the juice of Jerusalem Artichoke tubers.
The cell growth rate and ethanol production rate were stimulated by aeration and by the addition of unsaturated fatty acids
and the cell mass production and the ethanol production were substantially improved.
It was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of alcohol tolerance of
yeast. 相似文献