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21.
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。  相似文献   
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A stochastic damage accumulation model for crack initiation in high-cycle fatigue is proposed. It is assumed that the fatigue damage is accumulated in the form of dislocations under the repeated stress and that the slip band crack is initiated when the strain energy due to a local pile-up of dislocations exceeds a critical value. The size of an initiating crack is the cell size, derived from a probabilistic argument and its depth is determined in relation to the stored dislocation energy. Our theoretical results are compared with the experimental data from a low-carbon steel S20C in order to examine the consistency of our model.  相似文献   
24.
Decomposition of gaseous toluene and oxidation of CO on thermally excited titanium dioxide (TiO2)/silica (SiO2) composite material were investigated using a simple flow system. TiO2/SiO2 composite bead was superior to TiO2 (anatase) or TiO2/alumina in the thermally excited activation for toluene decomposition. The composite effect of TiO2/SiO2, bead was recognized in our study. ESR studies showed the existence of Ti3+ in the material. This means that oxygen vacancy would be generated by thermally excitation of TiO2 in the composite material.  相似文献   
25.
Summary The presence of Cr(CO)6 in nBuLi-initiated anionic polymerization of methyl methacrylates (MMA) was found to effectively enhance stereoselectivity of the polymerization in toluene at 0°C. nBuLi/Cr(CO)6 afforded an isotactic PMMA with 86 % of mm triad, and the polymers obtained with nBuLi/Cr(CO)6/tBuOK were rich in heterotactic structures (mr = ca. 54%). In both cases, the selectivity was improved in ca. 10% compared to those of the polymerization conducted under the similar conditions without Cr(CO)6. Received: 20 January 2003/Revised version: 21 April 2003/Accepted: 21 April 2003 Correspondence to Eiji Ihara  相似文献   
26.
Conceptual study of the process of hydrogen production by direct dissociation of water using high temperature solar energy is described. Calculated result of equilibrium composition of water vapour, hydrogen and oxygen suggests that temperatures above 3000 K are required for the dissociation of water. Considerations are made on a solar furnace for supplying such high temperature energy. Basic ideas on the method for separating hydrogen and oxygen from high temperature water vapour are suggested. Analysis of overall efficiency and target cost shows that the process will be justified for practical use if an effective separation method can be developed.  相似文献   
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Amyloid beta-protein (Abeta) is the major component of senile plaques that emerge in the cortex during aging and appear most abundantly in Alzheimer's disease. In the course of our immunocytochemical study on a large number of autopsy cases, we noticed, in many aged nondemented cases, the presence of unique diffuse plaques in the cortex distinct from ordinary diffuse plaques by immunocytochemistry. The former were amorphous, very faintly Abeta-immunoreactive plaques resembling diffuse plaques, but they stained for Abeta40 and were associated with small cells containing Abeta-positive granules. A panel of amino- and carboxyl-terminal-specific Abeta antibodies showed that such Abeta40-positive diffuse plaques and cell-associated granules were composed exclusively of amino-terminally deleted Abeta terminating at Abeta40, -42, and -43. Double immunostaining also showed that those Abeta-immunoreactive granules are located in astrocytes and not in microglia or neurons. Immunoelectron microscopy revealed that nonfibrillar Abeta immunoreactivity was located within lipofuscin-like granules in somewhat swollen astrocytes. These findings raise the possibility that astrocytes take up Abeta and attempt to degrade it in lysosomes in the aged brain.  相似文献   
29.
tau in paired helical filaments (PHF-tau) and fetal tau share several phosphorylated epitopes, as revealed by several phosphorylation-dependent PHF monoclonals. We have asked whether there is any difference between the two molecules in tubulin assembly-promoting activity and found that PHF-tau is almost assembly incompetent, whereas fetal tau is low in this activity but still assembly competent. This indicates that despite substantial similarities in immunoreactivities, PHF-tau and fetal tau are quite distinct from each other in function.  相似文献   
30.
A new approach for the synthesis of double-alkylated L-glutamide-derived stationary phases to use in RP-HPLC is described. TEM observation of lipid distearylglutamide (DSG) showed the formation of fibrous aggregates in methanol or in chloroform through intermolecular hydrogen bonding among the amide moieties while dibutylglutamide (DBG) cannot aggregate in aqueous or organic media due to its lower order of short alkyl chain. DSG and DBG were covalently bonded to silica via amino-propyl linkages. Lipid membrane analogues (e.g., DSG) attached to the silica surface have been found in noncrystalline and solid states and can form supramolecular assemblies with specific properties based on their highly ordered structures in aqueous and organic media. 13C CP/MAS NMR and suspension (in methanol)-state 1H NMR, elemental analysis, and DSC measurements were used to characterize Sil-DSG and were compared with the three other octadecyl phases, i.e., monomeric C18, polymeric C18, and silica grafted poly(octadecyl acrylate) Sil-ODA25. The chromatographic behavior of the new RP material was investigated using detailed retention studies of planar and nonplanar polyaromatic hydrocarbons (PAHs) and nonpolar aromatic positional isomers. Aspects of shape selectivity were also evaluated with Standard Reference Materials 869a, Column Selectivity Test Mixture for Liquid Chromatography. Detailed chromatographic study revealed that Sil-DSG showed extremely enhanced molecular shape selectivity compared with the other phases investigated. The higher molecular shape selectivity obtained by Sil-DSG can be explained by a carbonyl pi (present in lipid-grafted stationary phases)-benzene pi (present in guest PAHs) interaction mechanism, and these interactions are more effective for ordered carbonyl groups.  相似文献   
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