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排序方式: 共有1496条查询结果,搜索用时 15 毫秒
81.
Koichiro Koyama Masao Morishita Tomohiro Harada Nobuyuki Maekawa 《Metallurgical and Materials Transactions B》2003,34(5):653-659
The standard Gibbs energies of formation of Fe2Mo3O12, Fe2Mo3O8, FeMoO4, and Fe2MoO4 of the Fe-Mo-O ternary system and the μ phase of the Fe-Mo binary system have been determined by measuring electromotive forces of galvanic cells having an Y2O3-stabilized ZrO2 solid electrolyte. The results are as follows: $$\begin{gathered} \Delta _f G^\circ (FeMoO_4 )/kJ \cdot mol^{ - 1} = - 1053.5 + 0.2983(T/K) \pm 0.4 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_8 )/kJ \cdot mol^{ - 1} = - 2347 + 0.6814(T/K) \pm 1 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_{12} )/kJ \cdot mol^{ - 1} = - 2993 + 0.9105(T/K) \pm 2 \hfill \\ Temperature range: 1040 to 1145 K \hfill \\ \Delta _f G^\circ (Fe_{0.58} Mo_{0.42} )/kJ \cdot mol^{ - 1} = - 18.7 + 0.0117(T/K) \pm 0.1 \hfill \\ Temperature range: 1162 to 1223 K \hfill \\ \Delta _f G^\circ (Fe_2 MoO_4 )/kJ \cdot mol^{ - 1} = - 1174 + 0.342(T/K) \pm 1 \hfill \\ Temperature range: 1243 to 1466 K \hfill \\ \end{gathered} $$ where the standard pressure is 1 bar (100 kPa). 相似文献
82.
Profile structure of magnetic flux lines in type-II superconductor from a rectangular electron hologram 总被引:1,自引:0,他引:1
Harada K Beleggia M Endo J Kasai H Togawa Y Matsuda T Tonomura A 《Journal of electron microscopy》2003,52(4):369-373
Profile magnetic configuration of a quantized flux line and flux-line lattice penetrating a type-II superconductor thin foil, niobium, was observed by electron holography and Lorentz microscopy using a 300 kV field-emission electron microscope. Each single flux line was distributed periodically as lattice structure in the mixed state just below its critical temperature of 8.5 K, while at low temperature of 5 K the flux lines were weakly bound as bundles. In order to observe the flux-line distribution over a wide area, discrete Fourier transform reconstruction in the holography was extended for a rectangular area without loss of information and data precision. 相似文献
83.
Tsubota T Taki S Nakayama K Mason JI Kominami S Harada N Kita I 《Reproduction (Cambridge, England)》2001,121(4):587-594
The Japanese black bear, Ursus thibetanus japonicus, is a seasonal breeder and shows delayed implantation for several months during pregnancy. The objective of this study was to clarify the steroidogenic capability of the corpus luteum and placenta during pregnancy, including both delayed implantation and fetal development, by immunolocalization of steroidogenic enzymes in these organs of the Japanese black bear. Ovaries and placentae from 15 wild Japanese black bears, which had been killed legally by hunters and were thought to be pregnant, were used in an immunocytochemical study to localize the cholesterol side chain cleavage cytochrome P450 (P450scc), 3beta-hydroxysteroid dehydrogenase (3betaHSD), 17alpha-hydroxylase cytochrome P450 (P450c17) and aromatase cytochrome P450 (P450arom) by the avidin-biotin-peroxidase complex method using polyclonal antisera raised in mammals against P450scc, 3betaHSD, P450c17 and P450arom. P450scc and 3betaHSD were localized in all luteal cells throughout pregnancy. P450c17 was present in a few luteal cells, especially in the outer area of the corpus luteum throughout pregnancy, but the number of positively immunostained cells decreased during the post-implantation period. Cells positively immunostained for P450c17 were significantly smaller than negatively immunostained cells (P < 0.01). P450arom was present sporadically in a few luteal cells throughout pregnancy, but the number of positively immunostained cells decreased during the post-implantation period. The size of cells positively immunostained for P450arom was not significantly different from that of negatively immunostained cells. The whole placenta was negatively immunostained for P450scc, 3betaHSD and P450c17, but P450arom was present in the syncytiotrophoblasts and endothelial cells of maternal blood vessels. These results indicate that, in the Japanese black bear, corpora lutea are a source of progesterone which may play an important role in the maintenance of delayed implantation and fetal development during pregnancy. Corpora lutea have a minimum capability to synthesize androgen in small luteal cells and oestrogen in normal-sized luteal cells during pregnancy, and placentae have the ability to synthesize oestrogen during late pregnancy. 相似文献
84.
Laboratory accumulation and excretion experiments of 4-nonylphenols (NP) and 4-tert-octylphenol (OP) were performed for killifish (Oryzias latipes). The bioconcentration factors (BCF, wet weight) in the whole fish were mean +/- SD of 167 +/- 23 (n = 4) for NP and 261 +/- 62 (n = 4) for OP. The biological half-lives in the whole fish were 9.9 h for NP and 7.7 h for OP. Parallel to the laboratory experiments, field survey on the chemicals contamination for water and ayu fish (Plecoglossus altivelis) from rivers flowing into Lake Biwa was performed. The contamination was not so high in agreement with the laboratory experimental data and the field BCF values (wet weight) in the ayu fish were 21 +/- 15 (n = 8) for NP and 297 +/- 194 (n = 3) for OP. 相似文献
85.
H. Kakiuchi H. Ohmi M. Harada H. Watanabe K. Yasutake 《Science and Technology of Advanced Materials》2007,8(3):137-141
The formation of silicon dioxide (SiO2) layers at low temperatures (150-400 °C) by atmospheric pressure plasma oxidation of Si(0 0 1) wafers have been studied using a gas mixture containing He and O2. A 150 MHz very high frequency (VHF) power supply was used to generate high-density atomic oxygen in the atmospheric pressure plasma. Oxidation rate, structure, and thickness and refractive index profiles of the oxidized layers were investigated by ellipsometry and infrared absorption spectroscopy. Atomic force microscopy was also employed to observe atomic-scale morphologies of the layer surface and wafer Si surface, after chemical removal of the oxidized layers. It was found that stoichiometric SiO2 layers were obtained at higher oxidation rates than conventional dry O2 thermal oxidation and radical oxidation processes, even at a very low substrate temperature of 150 °C. Although thickness variations were observed in the plasma region, the refractive index was independent of both substrate temperature and VHF power. In addition, the SiO2 surface and SiO2/Si interface roughnesses were comparable to those obtained in conventional dry oxidation at high temperatures. 相似文献
86.
Monodispersed ellipsoidal hematite particles were synthesized and coated with silicone using a silane-coupling agent, phenyltriethoxysilane.
The thickness of the silicone shell was controlled by the concentration of phenyltriethoxysilane and the presence of n-hexadecyltrimethylammonium chloride, which was thought to modify the surface properties of the hematite particles to be organophilic.
The hematite/silicone core-shell particles were strongly hydrophobic and had a good dispersibility and stability in toluene.
Hollow ellipsoidal silicone particles were obtained by the dissolution of hematite with hydrochloric acid from the core-shell
particles. 相似文献
87.
Yasuyuki Kono Takehide Yano Tetsuro Chino Kaoru Suzuki Hiroshi Kanazawa 《Applied Artificial Intelligence》2013,27(4-5):487-518
Two requirements should be met in order to develop a practical multimodal interface system , i . e ., ( 1 ) integration of delayed arrival of data and ( 2 ) elimination of ambiguity in recognition results of each modality . This paper presents an efficient and generic methodology for interpretation of multimodal input to satisfy these requirements . The proposed methodology can integrate delayed - arrival data satisfactorily and efficiently interpret multimodal input that contains ambiguity . In the input interpretation the multimodal interpretation process is regarded as hypothetical reasoning , and the control mechanismof interpretation is formalized by applying the assumption - based truth maintenance system ( ATMS ). The proposed method is applied to an interface agent system that accepts multimodal input consisting of voice and direct indication gesture on a touch display . The systemcommunicates to the user through a human - like interface agent's three - dimensional motion image with facial expressions , gestures , and a synthesized voice . 相似文献
88.
Hidenobu Mizuki Yudai Ito Saba Samatya Hisashi Harada Hidetaka Kawakita 《溶剂提取与离子交换》2013,31(1):146-156
Abstract A novel adsorbent Zr(IV)-immobilized resin was prepared to remove fluoride ions from tap water and industrial wastewater. In order to enhance both the kinetics and efficiency, large pathways were formed in the resin for fluoride ion adsorption and the Zr(IV)-phosphate complexes were immobilized on the polymer surface by surface-template polymerization. The Zr(IV)-immobilized resin had a fluoride adsorption capacity of 0.30 mmol/g. The morphology of the Zr(IV)-immobilized resin was evaluated by measuring the specific surface area, pore volume, and pore size distribution. The resin possessed large amounts of large macropores with diameters around 300 nm. The molecular structure at the fluoride adsorption sites was investigated by measuring the amounts of phosphorus, zirconium, and fluoride ion in the resin, and developing a model complex using computational chemistry. On the polymer surface, a fluoride ion/Zr(IV)/dioleyl phosphoric acid complex with an ideal F:Zr:P mole ratio of 3:1:3 could be formed. 相似文献
89.
Mitsukazu Ochi Daisuke Nii Yasufumi Suzuki Miyuki Harada 《Journal of Materials Science》2010,45(10):2655-2661
Epoxy/zirconia hybrid materials were synthesized from a bisphenol-A type epoxy resin, zirconium-tetra-n-propoxide and acetic acid via in situ polymerization. Acetic acid was used to control the hydrolysis and condensation reaction
of the zirconium-tetra-n-propoxide. As a result, the zirconia produced by the in situ polymerization was uniformly dispersed into the epoxy matrix
on a nano scale or less, and the hybrid materials exhibited an excellent optical transparency. With the increasing zirconia
contents, the storage modulus in the rubbery region increased and the peak area of tanδ in the glass transition temperature
region decreased. These results indicate that their heat resistance of the hybrid materials could be improved by hybridization
with zirconia. Furthermore, the refractive indices of the hybrid materials were significantly improved with the increasing
zirconia contents. 相似文献
90.
This article describes a three-dimensional shape recognition method that employs an ultrasonic distance sensor mounted on a manipulator, and its application to a manipulator control system. The principle of the method is to reconstruct an object surface numerically using both distance and orientation informations of an object. The method makes it possible to control the manipulator, to set the sensor in any position and orientation employing freedom of the manipulator, and to measure the object. The method is available for manipulator control because it can precisely assess the distance from the manipulator to the object, as well as reconstruct the object shape. Experimental results show that the newly developed method make object shape recognition easy and inexpensive. Application experiment proved that the method is effective for manipulator work due to its provision of distance information. 相似文献