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31.
In order to determine the activities of phosphorus and iron in liquid {Cu‐Fe‐P} alloys, the two coexisting phases of liquid {Cu‐Fe‐P} alloys + <Cu‐Fe‐P> solid solutions were brought into equilibrium with a mixture of Al2O3 + AlPO4 + FexAl2O4 at temperatures of 1416K and 1526K. The oxygen partial pressures were measured with the aid of a solid‐oxide galvanic cell of the type: (+)Mo / Mo + MoO2/ ZrO2(MgO) / {Cu‐Fe‐P} + <Cu‐Fe‐P> + <Al2O3> + <AlPO4> + <FeAl2O4> / Fe(‐) The equilibrium reactions underlying the experiments can be expressed by 2[P]cu + (5/2) (O2) + <Al2O3> = 2 <AlPO4> and x[Fe]Cu + (1/2) (O2) + <Al2O3> = <FexAl2O4> The Henrian activity coefficient referred to 1 wt pct solution in pure liquid copper could be well expressed by the formula log fP° = (4.46±0.40) ‐ (8.67±0.59)/(T/K). The iron activities referred to pure solid iron could be formulated as log aFe =‐ (0.37 ± 0.12) + (500 ±200) /(T/K). 相似文献
32.
S.K. Sharma H. Zushi I. Takagi Y. Hisano T. Shikama S. Morita T. Tanabe N. Yoshida M. Sakamoto Y. Higashizono K. Hanada M. Hasegawa K. Nakamura H. Idei K.N. Sato S. Kawasaki H. Nakashima A. Higashijima Y. Takase 《Journal of Nuclear Materials》2012,420(1-3):83-93
In order to investigate the overall atomic hydrogen background and the dynamic characteristics of wall pumping/fuelling phenomenon, a permeation probe system has been developed and applied in the spherical tokamak QUEST. Reliability of measurements, within ±3% accuracy and a positive correlation with the hydrogen line emission over three orders of magnitude have been demonstrated for more than 3000 various plasma discharges. By comparison of the experimental permeation (flux) curves with the numerically simulated curves, the net incident atomic hydrogen flux is evaluated in the range of 1 × 1019 H m?2 s?1 to 4 × 1020 H m?2 s?1. The atomic flux has been investigated as a function of various plasma operation parameters like RF power, gas pressure and magnetic configuration. Using the static particle balance and permeation measurements, the progress in wall conditioning has been investigated. An inverse correlation between the atomic hydrogen flux and improvement in wall pumping has been observed over the two campaigns. 相似文献
33.
Toshio Hasegawa Takashi Fujita Yasutsugu Tsukumo Takashi Fujihara Daisuke Jing Atsushi Takahashi Kenta Nakajima 《食品科学与工程:英文版(2...》2014,(1):10-20
Although many aroma components have been identified in green tea leaves, the aroma compounds contributing to green tea's characteristic odor have not yet been reported. The authors recently reported that aroma components with a matcha-like odor are present in both green tea and black tea prepared from the Sayamakaori tea cuttivar. This matcha-like odor is similar to the odor of commercial available matcha (high-quality powdered green tea), and is a specific odor feature of green tea leaves. At present, the green-tea odor is thought to arise from the combination of a large number of constituents. Recent reports indicate that a complex interaction between olfactory receptors and odorants is important for the evaluation of the odors. Taking into consideration these findings, the authors investigated the aroma profile of green tea, focusing on the characteristic molecular structures of the constituents that give matcha-like odor. Using a combination of organic synthesis and gas chromatography-mass spectrometry plus gas chromatography-olfactometry, the authors identified aroma components with matcha-like odors in five other tea cultivars. This investigation also revealed that several compounds with a formyl group were important constituents of the aroma of green tea leaves, although the odor of each constituent was not individually similar to the tea's overall aroma. The authors found for the first time a group of key components that have the matcha-like odor. 相似文献
34.
Atopic dermatitis (AD) is a chronic pruritic skin disease with a complex pathogenesis underlying its heterogeneous clinical phenotypes and endotypes. The skin manifestation of AD reflects the cytokine milieu of a type-2-dominant immunity axis induced by genetic predisposition, innate immunity dysregulation, epidermal barrier defects, and allergic inflammation. However, the detailed pathomechanism of eczematous dermatitis, which is the principal characteristic of AD, remains unclear. This review examines previous studies demonstrating research progress in this area and considers the immunological pathomechanism of “spongiotic dermatitis”, which is the histopathological hallmark of eczematous dermatitis. Studies in this field have revealed the importance of IgE-mediated delayed-type hypersensitivity, the Fas/Fas-ligand system, and cell-mediated cytotoxicity in inducing the apoptosis of keratinocytes in spongiotic dermatitis. Recent studies have demonstrated that, together with infiltrating CD4 T cells, IgE-expressing dendritic cells (i.e., inflammatory dendritic epidermal cells and Langerhans cells) that capture specific allergens (i.e., house dust mites) are present in the spongiotic epidermis of lichenified eczema in patients with IgE-allergic AD. These findings suggest that IgE-mediated delayed-type hypersensitivity plays a pivotal role in the pathogenesis of spongiotic dermatitis in the skin lesions of AD. 相似文献
35.
Zijing Wang Fen Wang Angga Hermawan Yusuke Asakura Takuya Hasegawa Hiromu Kumagai Hideki Kato Masato Kakihana Jianfeng Zhu Shu Yin 《材料科学技术学报》2021,73(14):128-138
Acetone,as widely used reagents in industry and laboratories,are extremely harmful to the human.So the detection of acetone gas concentrations and leaks in special environments at room temperature is essential.Herein,the nanocomposite combining SnO-SnO2 (p-n junction) and Ti3C2Tx MXene was successfully synthesized by a one-step hydrothermal method.Because of the existence of a small amount of oxygen during the hydrothermal conditions,part of the p-type SnO was oxidized to n-type SnO2,forming in-situ p-n junctions on the surface of SnO.The hamburger-like SnO-SnO2/Ti3C2Tx sensor exhibited improved acetone gas sensing response of 12.1 (Rg/Ra) at room temperature,which were nearly 11 and 4 times higher than those of pristine Ti3C2Tx and pristine SnO-SnO2,respectively.Moreover,it expressed a short recovery time (9 s) and outstanding reproducibility.Because of the different work functions,the Schottky barrier was formed between the SnO and the Ti3C2Tx nanosheets,acting as a hole accumulation layer (HALs) between Ti3C2Tx and tin oxides.Herein,the sensing mechanism based on the formation of hetero-junctions and high conductivity of the metallic phase of Ti3C2Tx MXene in SnO-SnO2/Ti3C2Tx sensors was discussed in detail. 相似文献
36.
Mitsuhiro Shikida Yosuke Niimi Tatsuya Hasegawa Tomoaki Sugino Satoshi Hamaoka Kenji Fukuzawa 《Microsystem Technologies》2015,21(3):661-668
Mechanical strengthening of a Si cantilever by applying KOH wet etching was investigated. Two kinds of Si cantilever specimens having the different crystallographic orientations of the sidewall surfaces, i.e., Si{100} and Si{110}, were fabricated from the same SOI wafer by a Bosch process. The typical height and pitch of the scalloping formed on the sidewall were 248 and 917 nm, respectively. A 50 % KOH (40 °C) chemical wet etching was applied to increase the fracture stress of the Si cantilever. The fracture stress in the both of Si{100} and Si{110} cantilevers increased with the advance of the etching. The obtained maximum fracture stress in Si{100} and Si{110} were 4.2 and 3.7 GPa, respectively. Sidewall surface of the cantilever was analyzed to investigate the mechanical strengthening of Si cantilever by wet etching. The etched surface crystalline was analyzed by the transmission electron microscope (TEM), and confirmed that the thickness of the affected flow layer was less than 10 nm from the obtained TEM image. Then the change of the surface roughness by the KOH etching was analyzed by the atomic force microscope. The surface was smoothened with the advance of the KOH etching. The roughness value of Ra in Si{100} and Si{110} decreased to 12.1 and 37.7 nm, respectively. 相似文献
37.
Wada M Kawabata H Yoshizumi A Kataoka M Nakamori S Yasohara Y Kizaki N Hasegawa J Shimizu S 《Journal of Bioscience and Bioengineering》1999,87(2):144-148
Multiple ethyl 4-chloro-3-oxobutanoate (COBE)-reducing enzymes were isolated from a cell-free extract of Candida magnoliae. A NADPH-dependent COBE-reducing enzyme, distinct from the carbonyl reductase and aldehyde reductase previously reported, was purified to homogeneity using five steps, including polyethylene glycol treatment. The relative molecular mass of the enzyme was estimated to be 86,000 on high performance gel-permeation chromatography and 29,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme catalyzed the reduction of COBE to the corresponding (S)-alcohol with a 51% enantiomeric excess. The substrate specificity of the enzyme was different from those of the other COBE-reducing enzymes of the same strain. The partial amino acid sequences of the enzyme showed that it belongs to the short chain alcohol dehydrogenase/reductase (SDR) family. This is the first report of multiple COBE-reducing enzymes with various stereoselectivities occurring in the same strain but belonging to different (super)families. 相似文献
38.
We propose an axiomatization of fixpoint operators in typed call-by-value programming languages, and give its justifications in two ways. First, it is shown to be sound and complete for the notion of uniform T-fixpoint operators of Simpson and Plotkin. Second, the axioms precisely account for Filinski's fixpoint operator derived from an iterator (infinite loop constructor) in the presence of first-class continuations, provided that we define the uniformity principle on such an iterator via a notion of effect-freeness (centrality). We then explain how these two results are related in terms of the underlying categorical structures. 相似文献
39.
We studied the improvement of heat resistance and mechanical properties of phenolic resin modified with polymers prepared from p-hydroxyphenylmaleimide (HPMI). Homopolymers of HPMI and copolymers of HPMI with some vinyl monomers were synthesized and Mn Tg and thermal decomposition temperature of them were measured by GPC, DSC, and TG, respectively. The miscibility of homopolymer with novolac was examined by DSC. It was found that the homopolymer had good heat resistance and good miscibility with novolac. Molding compounds were prepared by hot roll-kneading the mixtures of novolac, the homopolymer, hexamethylenetetramine, and glass fiber. It was found that molded test pieces had good heat resistance. 相似文献
40.
l-Tryptophan caused growth inhibition of roots and hypocotyls (or coleoptiles) of cockscomb (Amaranthus caudatus L.), lettuce (Lactuca sativa L.), cress (Lepidium sativum L.), timothy (Phleum pratense L.), rice (Oryza sativa L.), wheat (Triticum aestivum L.), and oat (Avena sativa L.), increasing the dose ofl-tryptophan increased the inhibition. The concentrations for 50% inhibition of the root growth were 0.14, 0.15, 0.21, 0.79, 0.95, 1.7, and 2.4 mM for cockscomb, cress, lettuce, timothy, rice, wheat, and oat, respectively; the concentrations for 40% inhibition of the hypocotyl (or coleoptile) growth were 0.28, 0.33, 0.43, 2.7, 4.5, 7.2, and 15 mM for cockscomb, cress, lettuce, timothy, rice, wheat and oat, respectively. The levels ofl-tryptophan in oat seedlings and in its root exudates were 29.3 mg/kg fresh wt and 0.25 mM under light conditions, and 21.1 mg/kg fresh wt and 0.18 mM under dark conditions, respectively. The presence ofl-tryptophan in the root exudates coupled with its effect on growth suggested thatl-tryptophan may play an important role in the growth inhibition of other plants in nature. 相似文献