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1.
Porous alumina with a highly textured microstructure was fabricated by pulse electric current sintering (PECS) using alumina platelets. Highly oriented porous alumina with a porosity of 3%–50% was obtained by a pressure-controlled method of PECS. The properties of the highly textured porous alumina were measured in two directions. The nitrogen gas permeance and thermal conductivity at room temperature were higher in the direction along the platelet length due to the higher continuity of pores and the connectivity of alumina platelets, respectively. The anisotropy of the thermal conductivity at room temperature was investigated and explained by the effect of grain size of platelets as well as morphology and orientation of pores. The bending strength was higher with the loading direction along the platelet thickness. The thermal shock strength was clearly different in the two directions. The difference in the thermal shock strength was investigated by the measurement of properties and thermal stress analysis.  相似文献   
2.
A 640-Gb/s high-speed ATM switching system that is based on the technologies of advanced MCM-C, 0.25-μm CMOS, and optical wavelength-division-multiplexing (WDM) interconnection is fabricated for future broadband backbone networks. A 40-layer, 160×114 mm ceramic MCM forms the basic ATM switch module with 80-Gb/s throughput. It consists of 8 advanced 0.25-μm CMOS LSIs and 32 I/O bipolar LSIs. The MCM has a 7-layer high-speed signal line structure having 50-Ω strip lines, high-speed signal lines, and 33 power supply layers formed using 50-μm thick ceramic layers to achieve high capacity. A uniquely structured closed-loop-type liquid cooling system for the MCM is used to cope with its high power dissipation of 230 W. A three-stage ATM switch is made using the optical WDM interconnection between high-performance MCMs. For WDM interconnection, newly developed compact 10-Gb/s, 8-WDM optical transmitter and receiver modules are used. These modules are each only 80×120×20 mm and dissipate 9.65 W and 22.5 W, respectively. They have a special chassis for cooling, which contains high-performance heat-conductive plates and micro-fans. An optical WDM router based on an arrayed waveguide router is used for mesh interconnection of boards. The optical WDM interconnect has 640-Gb/s throughput and simple interconnection  相似文献   
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The presence of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) activities was determined in milk and serum of cows with naturally occurring coliform mastitis (CFM). TNF-alpha was detected in the sera from 26 of 32 cows with CFM. TNF-alpha levels were higher in the sera than in the milk. IL-6 was high in the sera of surviving CFM animals, but was low in animals that died and in healthy controls. Furthermore, the mean level of IL-6 was 20-fold higher in the milk than in the sera of mastitic cows. The level of IL-6 in the serum was correlated to that in the milk in individual animals. The presence of IL-6 and TNF-alpha in the sera appears to relate to severe clinical condition of CFM, in the milk whereas they may play a role in generating inflammation of the mammary gland.  相似文献   
5.
When zinc oxide and graphite were placed into an alumina crucible, with a square hole (∼3 mm ×∼3 mm) near the top, and the crucible was covered by an alumina lid and heated at >1050°C, a hollow polycrystal composed of needlelike, ribbon(comb)-like, dendritic, and bulk zinc oxide crystals grew from the hole toward the outside of the crucible. The diameter and length of the polycrystal grown at 1050°C after 1 h were ∼2.2 mm and ∼20 cm, respectively. The diameter increased, while the length decreased, with increasing temperature. Most of the needlelike zinc oxide crystals in the hollow polycrystal were elongated along the c -axis.  相似文献   
6.
Starting with a previously isolated cDNA for human thyrotropin receptor (TSHR), we established a transformed myeloma cell line, SP56, which expresses human TSHR on its cell surface. Binding analysis showed that SP56 bears 1.1 x 10(5) TSHR per cell with a Kd of 2.2 x 10(-10) M. Using the purified cellular membrane, we established a TSH binding inhibition immunoglobulin (TBII) assay for autoantibodies against TSHR. We compared it with the TBII assay utilizing porcine thyroid membranes expressing porcine TSHR, which has been widely used for TBII assay, by using 96 serum samples from patients with autoimmune thyroid disease and normal individuals. Our TBII assay was more sensitive than the one using porcine TSHR: of 38 sera of patients which were judged negative for autoantibodies to TSHR (TBII value below 10%) by the latter assay, 28 were positive (above 20%) in our assay. By using a perfusion culture system, we obtained as many as 3 x 10(10) SP56 cells, from which 3,450 mg protein of the membrane could be purified; this is sufficient for 15,000 assays. The results indicate that the membrane of the myeloma cell line SP56 is more suitable for use in the TBII assay than the porcine thyroid membrane, in terms of sensitivity to autoantibodies against TSHR in human sera.  相似文献   
7.
The texture of fibrous calcium hydroxyapatite (Ca10-(PO4)6(OH)2, CaHAP) particles that were prepared by the decomposition of calcium–ethylenediaminetetraacetic acid (calcium–EDTA) chelates at 100°C under various pH conditions (pH values of 5–10) was investigated by various means. Well-crystallized fibrous CaHAPs were produced at pH .6. The stoichiometry of the CaHAPs with a chemical formula of Ca10− x (HPO4) x (PO4)6− x (OH)2− x (H2O) x was improved by increasing the decomposition pH. All the CaHAPs had unit-cell dimensions of a = 0.9436 ± 0.0003 nm and c = 0.6881 ± 0.0006 nm, exhibiting an enlarged a value. The finding of mesoporosity of CaHAPs by nitrogen gas (N2) adsorption measurement indicated that the CaHAPs were produced by an agglomeration of primary particles. Furthermore, the nonstoichiometric CaHAPs that formed at pH 6 developed ultramicropores, which were accessible to water (H2O) molecules but not to N2 molecules, by the elimination of H2O molecules that were adsorbed in interstices of primary particles in less-orderly crystallized CaHAPs and/or by dehydration of HPO42− groups. These findings by gas adsorption techniques could give evidence for the agglomeration mechanism to attain a polycrystalline CaHAP, although they exhibited good crystallinity with large size.  相似文献   
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Composite bodies in the system Al–Zr–C, with about 95% relative density, were obtained by heating the compact body of powder mixture consisting of Al and ZrC (5 : 1 mol %) in Ar at 1100–1500°C for various lengths of time. Components of the material heated at more than 1200°C were Al, Al3Zr, ZrC and AlZrC2. The Al3Zr exhibited plate-like aggregation, and its size increased with increasing temperature. In the material heated at 1500°C for 1 h, the largest plate-like Al3Zr aggregation was 2000 m long and 133 m thick. Then the AlZrC2 was present as well-proportioned hexagonal platelet particles with a 8–9 m diameter and a 1–2 m thickness in the interior of the plate-like Al3Zr aggregation and Al matrix phase. The average three-point bending strength of the bodies was 140–190 MPa, and the maximum strength was 203 MPa in the body heated at 1300°C for 1 h. The body heated at 1500°C for 1 h showed high oxidation resistivity to air up to 1000°C.  相似文献   
10.
Cognitive dissonance and effects of self-affirmation on dissonance arousal were examined cross-culturally. In Studies 1 and 2, European Canadians justified their choices more when they made them for themselves, whereas Asian Canadians (Study 1) or Japanese (Study 2) justified their choices more when they made them for a friend. In Study 3, an interdependent self-affirmation reduced dissonance for Asian Canadians but not for European Canadians. In Study 4, when Asian Canadians made choices for a friend, an independent self-affirmation reduced dissonance for bicultural Asian Canadians but not for monocultural Asian Canadians. These studies demonstrate that both Easterners and Westerners can experience dissonance, but culture shapes the situations in which dissonance is aroused and reduced. Implications of these cultural differences for theories of cognitive dissonance and self-affirmation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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