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51.
We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films.  相似文献   
52.
Rod-shaped BaTiO3 powder particles have been prepared from rod-shaped TiO2 ·nH2O and BaCO3 in molten chloride. The morphology of BaTiO3 particles was studied referring to the effects of the chemical species of the starting titanium compound, amount of chloride, particle size of the titanium compound and reaction conditions, and the preparation condition of rod-shaped BaTiO3 has been determined: i.e., large TiO2 ·nH2O particles were heated at 700°C in molten salt with an equal amount of BaTiO3. This condition was effective in suppressing the formation of BaTiO3 by a solution-precipitation process as well as the deformation of either TiO2 ·nH2O or BaTiO3, which are responsible for the formation of equiaxed BaTiO3 particles. The obtained rod-shaped BaTiO3 particles had a cubic symmetry. Electron diffraction analysis showed that the following topotactic relation is retained; 0 1 0potassium tetratitanate 0 1 0hydrated titania 1 0 0anatase 1 0 0barium titanate  相似文献   
53.
Chemokines secreted from stromal cells have important roles for interactions with carcinoma cells and regulating tumor progression. C-C motif chemokine ligand (CCL) 5 is expressed in various types of stromal cells and associated with tumor progression, interacting with C-C chemokine receptor (CCR) 1, 3 and 5 expressed in tumor cells. However, the expression on CCL5 and its receptors have so far not been well-examined in human breast carcinoma tissues. We therefore immunolocalized CCL5, as well as CCR1, 3 and 5, in 111 human breast carcinoma tissues and correlated them with clinicopathological characteristics. Stromal CCL5 immunoreactivity was significantly correlated with the aggressive phenotype of breast carcinomas. Importantly, this tendency was observed especially in the CCR3-positive group. Furthermore, the risk of recurrence was significantly higher in the patients with breast carcinomas positive for CCL5 and CCR3 but negative for CCR1 and CCR5, as compared with other patients. In summary, the CCL5-CCR3 axis might contribute to a worse prognosis in breast cancer patients, and these findings will contribute to a better understanding of the significance of the CCL5/CCRs axis in breast carcinoma microenvironment.  相似文献   
54.
New biomarkers are needed to further stratify the risk of malignancy in intraductal papillary mucinous neoplasm (IPMN). Although microRNAs (miRNAs) are expected to be stable biomarkers, they can vary owing to a lack of definite internal controls. To identify universal biomarkers for invasive IPMN, we performed miRNA sequencing using tumor-normal paired samples. A total of 19 resected tissues and 13 pancreatic juice samples from 32 IPMN patients were analyzed for miRNA expression by next-generation sequencing with a two-step normalization of miRNA sequence data. The miRNAs involved in IPMN associated with invasive carcinoma were identified from this tissue analysis and further verified with the pancreatic juice samples. From the tumor-normal paired tissue analysis of the expression levels of 2792 miRNAs, 20 upregulated and 17 downregulated miRNAs were identified. In IPMN associated with invasive carcinoma (INV), miR-10a-5p and miR-221-3p were upregulated and miR-148a-3p was downregulated when compared with noninvasive IPMN. When these findings were further validated with pancreatic juice samples, miR-10a-5p was found to be elevated in INV (p = 0.002). Therefore, three differentially expressed miRNAs were identified in tissues with INV, and the expression of miR-10a-5p was also elevated in pancreatic juice samples with INV. MiR-10a-5p is a promising additional biomarker for invasive IPMN.  相似文献   
55.
The effect of particle agglomeration on sintering has been studied by slipcasting suspensions with pH values ranging from 2 to 11. The rate of densification has been found to depend on the degree of agglomeration. Complete dispersion of alumina primary particles has not been attained through adjustment of pH of suspensions, and agglomerates also remained in the best-dispersed suspension. Elimination of the agglomerates by sedimentation lowered the densification temperature of slip-cast compacts. The grain size-density curve is a function of temperature. High-density and small-grained sintered bodies were obtained by low-temperature long-time firing.  相似文献   
56.
A study has been made of ‘combined’ joints consisting of mechanical fastening and adhesive bonding between rigid adherends. The mechanical characteristics of such ‘hybrid’ butt and lap shear joints have been derived by theoretical analysis. Results from experimental tests in combined joints giver reasonable agreement with the theoretical equations relating joint load to deformation.  相似文献   
57.
Bondability and interfacial reaction between dielectric and insulator layers have been examined to obtain a basic understanding of bonding mechanisms. Lead-containing complex perovskite was used as a dielectric material. Two kinds of glass-ceramics were used as insulator material; lead borosilicate glass containing Al2O3 (insulator A) and the same containing Al2O3 and MgO (insulator B). Dielectric and insulator layers did not bond when insulator A was used. When insulator B was used, however, strong bonding was achieved between the two layers by firing the powder compacts at temperatures between 800° and 1000°C. Addition of MgO to lead borosilicate glass increased the thermal expansion coefficient to that of the dielectric and enhanced the formation of reaction layers, resulting in good bonding. Two reaction layers were identified. The main reaction products were enstatite and bredigite for one layer contacting the dielectric, and enstatite and a compound with the same diffraction pattern as that of faujasite for the other layers contacting insulator B.  相似文献   
58.
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses.  相似文献   
59.
Blending a crosslinked high‐density polyethylene (xHDPE) enhances melt strength and strain hardening behavior in elongational viscosity of high‐density polyethylene (HDPE) to a great degree. Gel fraction of xHDPE has a stronger effect on the strain hardening than sol fraction, although sol fraction also enhances the strain hardening to some degree. Further, the xHDPE crosslinked by peroxide in a compression mold exhibits more pronounced effect than xHDPE by radiation, which is attributed to the difference in the amount of the gel fraction. The xHDPE, which enhances the strain hardening, has sparse crosslink points in the network. Moreover, it was found from linear viscoelastic measurements, such as oscillatory modulus and relaxation modulus, that the xHDPE is characterized as a critical gel, which was also supported by the result of tensile testing. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 73–78, 2002  相似文献   
60.
A previous study has shown that the adhesion between the film and substrate of film‐insert injection‐molded poly(propylene) (PP) film/PP substrate was evident with the increases in barrel temperature and injection holding pressure. In this second part of the research work, the crystallinity at the interfacial region (i.e., region between the film and the injected substrate) was extensively studied using FTIR imaging, polarized light microscopy, and DSC in an attempt to determine the level of influence that crystallinity has on the interface and bulk mechanical properties. Consequently, a more thorough and clearer picture of the influence of the inserted film on the interfacial crystallinity and subsequently the substrate mechanical properties, such as peel strength and impact strength, has been revealed. The initial proposition that crystallinity could enhance film–substrate interfacial bonding has been confirmed, judging from the higher peel strength with increasing crystallinity at the interfacial region. Nevertheless, the change in crystallinity was not only confined to the interfacial region. With the film acting as heat‐transfer inhibitor between the injected resin and the mold wall, the total crystal structure of the substrate was substantially altered, which subsequently affected the bulk mechanical properties. The lower impact strength of film‐insert injection‐molded samples compared to that of samples without film inserts provided evidence of how the film could impart inferior properties to the substrate. The difference in cooling rate between the substrate and film might also cause other defects such as warpage and/or residual stress build‐up within the product. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 294–301, 2005  相似文献   
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