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71.
The activities of FexO in CaO + CaF2 + SiO2 + FexO quaternary slags were measured by means of solid-oxide galvanic cell. The FexO activities in the slags are influenced by CaF2 as well as SiO2. At constant FexO mole fractions, e.g., , at low SiO2 mole fractions i.e., , the substitution of CaF2 for CaO has an effect of raising the FexO activity. At higher SiO2 mole fractions, e.g., , however, such an effect becomes insignificant.  相似文献   
72.
The change of the conductivity in the rare earth perovskite oxide took place after the chemisorption of flammable gases. The sensitivity for methanol was highest. From the conductivity change of these perovskite oxides after the injection of methanol, the energy needed to promote an electron from a conducting to a nonconducting state, E=E c-E t, could be derived from the equation=A 0 exp (–E/kT). LnCoO3 had the smallest E and H (metal-O), which is the binding energy of oxygen coordinating to the metal ions, but exhibited the highest activity for gas sensing. The gas sensing mechanism was also considered.  相似文献   
73.
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   
74.
Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is causally related to fibrotic diseases, including idiopathic pulmonary fibrosis. The identification of Compounds that interfere with the HSP47-collagen interaction is essential for the development of relevant therapeutics. Herein, we prepared human HSP47 as a soluble fusion protein expressed in E. coli and established an assay system for HSP47 inhibitor screening. We screened a natural and synthetic Compound library established at Nagasaki University. Among 1023 Compounds, 13 exhibited inhibitory activity against human HSP47, of which three inhibited its function in a dose-dependent manner. Epigallocatechin-3-O-gallate, one of these three Compounds, is a typical polyphenol Compound derived from tea leaves. Structurally related Compounds were synthesized and examined for their activity, revealing a hydroxyl group at A-ring position 5 as important for its activity. The present findings provide valuable insight for the development of natural product-derived therapeutics for fibrotic diseases, including idiopathic pulmonary fibrosis.  相似文献   
75.
Using low-rank coals, the modifying activities of some petroleum, coal tar and aromatic hydrocarbon additives have been examined to find procedures for their utilization in the preparation of blast furnace coke. Petroleum pitch, especially after hydrogenation, exhibited excellent modifying activity even with non-fusible coals. In contrast, the activity of coal tar was very limited with such coals. The napththenic component, revealed by n.m.r. of the additives, appears to be important in the co-carbonization by inducing fusibility and anisotropic development in such coals. Co-carbonization to recover the dehydrogenated additives was attempted. However, there was no development of the anisotropy in the resultant coke by dissolution of the coal particles although the coal particles were firmly fixed in the matrix. Acid-refluxing treatment of non-fusible coals was found to enhance their modification susceptibility, indicating that some of the acid-soluble mineral matter is important in the thermal depolymerization or fusion process of the coal.  相似文献   
76.
The ironmaking blast furnace is regarded as one of the biggest and most complex industrial reactors, because it includes various materials like gas, lump granular materials, liquids and powders and more than 30 major reactions and phase changes in a single reaction vessel. The mathematical simulator of this process developed in this study used the multi-fluid treatment as its framework, since the motions of these materials were governed by different flow mechanisms. The rates of the interactions among the phases and the chemical reactions were evaluated based on kinetic theories. The model successfully reproduced the fields of velocity, temperature and reaction in the furnace and its validity was confirmed. The simulator was also applied to a novel operation, namely the top gas recycling combined with the carbon-composite iron-ore charging and the waste plastics injection, and the advantages in furnace efficiency and environmental load were quantitatively indicated.  相似文献   
77.
Thermal decomposition of aluminum isopropoxide in toluene at 315°C resulted in χ-alumina that had high thermal stability, whereas the reaction at lower temperatures resulted in formation of an amorphous product. The χ-alumina thus obtained directly transformed to α-alumina at ∼1150°C, bypassing the other transition alumina phases, whereas the amorphous product transformed to γ-alumina and then to θ-alumina before final transformation to α-alumina. When the χ-alumina, solvothermally synthesized at 315°C, was recovered by the removal of the solvent at the reaction temperature, thermal stability of the product was improved further. This procedure is convenient because it avoids bothersome work-up processes that yield large-surface-area and large-pore-volume alumina.  相似文献   
78.
Melting temperature of a film biaxially stretched in one step in air at 152 or 140°C increases with increase of vA, whereas heat of fusion and density decrease with increase of vA, where vA is the degree of stretching in area. The rapid decrease in density occurs for vA > 10. Extrapolation of the plot of the density versus vA?1/2 gives a value of 0.870 g/cm3 at infinite vA, which has been reported as the amorphous density of isotactic polypropylene by Farrow. This is so because the fine structure of the film becomes more and more amorphous with further stretching and reaches completely amorphous state at infinite vA. The temperature of stretching has a strong effect on the thermal behavior of a film; a low stretching temperature (140°C) brings about lower melting temperature, heat of fusion, and density. Crystallinity after melt press has not so large an effect on the melting behavior as the stretching temperature. Melting temperature and the shape of the thermogram also depend on the heating rate. There is an appropriate heating rate depending on vA which gives the minimum melting temperature. With stretched samples, a small side peak or a shoulder appears at a relatively low temperature in the thermogram when a high heating rate is used.  相似文献   
79.
Miscibility between acrylic copolymers and tackifier resins are investigated in terms of phase diagrams, and the probe tack of the blends are measured as a function of both temperature and rate of separation in order to obtain the master curves. It is found that the probe tack of the pressure sensitive adhesives are closely related to the miscibility between the components. The master curves of the miscible blends shift along the X(rate)-axis according to the change of Tg of the bulk materials with a gradual variation of the peak heights. However, those of the immiscible blends will not shift along the X(rate)-axis, but the magnitude will decrease with increase of a dispersed phase.  相似文献   
80.
An isotactic polypropylene hollow microfiber was continuously produced by using a carbon dioxide (CO2) laser‐thinning method. To prepare the hollow microfiber continuously, the apparatus used for the thinning of the solid fiber was improved so that the laser can circularly irradiate to the hollow fiber. Original hollow fiber with an outside diameter (OD) of 450 μm and an internal diameter (ID) of 250 μm was spun by using a melt spinning machine with a specially designed spinneret to produce the hollow fiber. An as‐spun hollow fiber was laser‐heated under various conditions, and the OD and the ID decreased with increasing the winding speed. For example, when the hollow microfiber obtained by irradiating the CO2 laser to the original hollow fiber supplied at 0.30 m min?1 was wound up at 800 m min?1, the obtained hollow microfiber had an OD of 6.3 μm and an ID of 2.2 μm. The draw ratio calculated from the supplying and the winding speeds was 2667‐fold. The hollow microfibers obtained under various conditions had the hollowness in the range of 20–30%. The wide‐angle X‐ray diffraction patterns of the hollow microfibers showed the existence of the highly oriented crystallites. Further, the OD and ID decreased, and the hollowness increased by drawing hollow microfiber obtained with the laser‐thinning. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2600–2607, 2006  相似文献   
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