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101.
Humidity Sensor Characteristics of Woodceramics 总被引:9,自引:0,他引:9
Kiyokazu Kasai Kiyotaka Shibata Koji Saito Toshihiro Okabe 《Journal of Porous Materials》1997,4(4):277-280
The humidity sensor characteristics of Woodceramics were investigated. The Woodceramics used in this experiment were prepared at 650–900°C. The size of specimens selected was 1 × 1 × 10 mm . One was used as-cut and the other was polished. Above 700°C, the resistance of the specimen was below 50 and the decrease of resistance with increasing relative humidity was small. The specimen prepared at 650°C had a resistance of about 1 k. The resistance of as-cut specimens decreased with increase in relative humidity, but that of the polished specimen did not change significantly. The difference between as-cut and polished samples was explained by the differences in surface micro-structure. 相似文献
102.
Laser-Sintered Barium Titanate 总被引:1,自引:0,他引:1
Toshihiro Kasai Yoshiharu Ozaki Hideki Noda Kenji Kawasaki Kei Tanemoto 《Journal of the American Ceramic Society》1989,72(9):1716-1718
Laser sintering of alkoxy-derived ultrafine BaTiO3 powders was investigated. The temperature increases of the sample with laser irradiation were measured with a thermocouple. It was found that laser irradiation could generate enough heat to sinter ceramics. A slurry was prepared by mixing an alkoxy-derived BaTiO3 powder, binder additives, solvent, and plasticizer. The slurry was tape cast and dried to give a green sheet. The green sheet was laser sintered and was then characterized by SEM, XRD, and density measurements. The effect of burnout before laser irradiation and the characteristic microstructure of laser-sintered BaTiO3 are described. 相似文献
103.
We examined the influence of polyaniline (PAn)'s unit sequence and doping with low molecular weight dopants or polymer dopants on permeation property. It was found that CO2 permeability was increased by the formation of a quinonediimine unit in PAn with the oxidation. CO2 sorption amount of PAn was decreased by oxidation. The increase of CO2 permeability with oxidation, therefore, resulted from the increase of diffusivity, which was attributable to morphological variation by the increase of a quinonediimine unit. The permselectivity of PAn films was found to be remarkably improved by doping. In particular, the selectivity value of the PAn film doped with polyvinyl sulphonic acid as a polymer dopant went up to over 2,000. This remarkable increase of selectivity was found to result in the increase of selectivity, depending on diffusivity. It was also found that the permselectivity of the PAn film doped by polymer dopants was surpassed, as compared with that doped by low molecular dopants. © 1995 John Wiley & Sons, Inc. 相似文献
104.
Toshio Kimura Toru Takahashi Toshihiko Tani Yasuyoshi Saito 《Journal of the American Ceramic Society》2004,87(8):1424-1429
Bi0.5 Na0.5 TiO3 (BNT) and 0.94Bi0.5 Na0.5 TiO3 ·0.06BaTiO3 (BNT–BT) bulk ceramics with extensive 〈100〉 texture were prepared by the reactive-templated grain growth method, using platelike Bi4 Ti3 O12 (BIT) particles as templates for BNT. Calcined compacts were composed of matrix grains with random orientation and 〈100〉-oriented grains transformed from aligned BIT particles, and the texture developed by the growth of oriented grains during sintering. Ceramics with extensive texture were obtained by using the starting mixture containing the maximum concentration of platelike BIT to form the maximum volume fraction of oriented grains. 相似文献
105.
106.
The wax esters of sperm whale head oil have been characterized by gas-liquid chromatography on an APOLAR 10C column according
to their carbon number and number of double bonds. The novel technique permits the direct quantitative analysis of saturated
and unsaturated wax esters. 相似文献
107.
Keizo Uematsu Jin-Young Kim Masayori Miyashita Nozomu Uchida Katsuichi Saito 《Journal of the American Ceramic Society》1990,73(8):2555-2557
The internal structure of spray-dried alumina granules was characterized by optical microscopy by immersing them in a liquid having a refractive index close to that of alumina. This method provides a unique technique for the detailed analysis of the internal structure of spray-dried granules. 相似文献
108.
高速气流冲击式粉体表面改性装置——HYBRIDIZATION系统及应用 总被引:4,自引:0,他引:4
利用高速气流冲击法进行粉体/粉体系表面改性技术,是迄今为止各种粉体材料开发中最为引人注目的技术之一。HYBRIDIZATION(下称HYB)系统是利用高速气流冲击法对微粉体进行干式/机械化处理,是使材料复合化的最实用的装置,可对各类有机物、无机物、金属等进行广泛组合,通用性很强,适用于许多行业领域。从本文所述的系统构成、型式,有关的典型球形化处理的运转特性,利用复合化高温粉体测定被处理粉体表面温度,利用颜料改变色调等的处理特点及该系统的适用性等(一部分是从已发表的学术论文及专利上摘录的),可以说明HYB系统的概况。 相似文献
109.
PTCR characteristics in porous semiconducting barium titanate ceramics with Curie points from 60° to 360°C were investigated. The magnitude of the PTCR effect in these cerumics decreases self-onsistently with increasing Curie point within this temperature range. A PTCR efSect of more than 4 orders of magnitude was ahserved, for a Ba0.44 Pb0.6 TiO3 ceramic with a Curie point of 360°C . 相似文献
110.
To model the molten globule structure of -lactalbumin, moleculardynamics (MD) simulations were carried out for the protein inexplicit water at high temperature. In these simulations, long-rangeCoulomb interactions were evaluated explicitly with an originalmethod (particleparticle and particlecell: PPPC)to avoid artifacts caused by the cut-off. The MD simulationswere started from two initial conditions to verify that similarresults would be obtained. From the last 150 ps trajectoriesof the two MD simulations, two partially unfolded average structureswere obtained. These structures had the following common structuralfeatures which are characteristic of the molten globule state.The radii of gyration for these conformations were 7.4 and 9.6%larger than that of the native state. These values were almostthe same as the experimental value (9.6%) observed recentlyby small-angle X-ray scattering (Kataoka,M., Kuwajima,K., Tokunaga,F.and Goto,Y., 1997, Protein Sci., 6, 422430). Furthermore,aromatic residues of clusters I and II in these structures werefar apart from each other except for Try103Trp104. Thisresult is in good agreement with NMR experimental results forthe acid-denatured molten globule state (Alexandrescu et al.,1992, 1993); that is, NOE signals between the aromatic residueswere not observed, except for that of Try103Trp104 inthe molten globule state. Other structural features of thesemodels for the molten globule state are discussed with referenceto native state structures. 相似文献