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排序方式: 共有7126条查询结果,搜索用时 31 毫秒
1.
Akira Yamamoto Kentaro Teramura Saburo Hosokawa Tsunehiro Tanaka 《Science and Technology of Advanced Materials》2015,16(2)
The effect of SO2 gas was investigated on the activity of the photo-assisted selective catalytic reduction of nitrogen monoxide (NO) with ammonia (NH3) over a TiO2 photocatalyst in the presence of excess oxygen (photo-SCR). The introduction of SO2 (300 ppm) greatly decreased the activity of the photo-SCR at 373 K. The increment of the reaction temperature enhanced the resistance to SO2 gas, and at 553 K the conversion of NO was stable for at least 300 min of the reaction. X-ray diffraction, FTIR spectroscopy, thermogravimetry and differential thermal analysis, x-ray photoelectron spectroscopy (XPS), elemental analysis and N2 adsorption measurement revealed that the ammonium sulfate species were generated after the reaction. There was a strong negative correlation between the deposition amount of the ammonium sulfate species and the specific surface area. Based on the above relationship, we concluded that the deposition of the ammonium sulfate species decreased the specific surface area by plugging the pore structure of the catalyst, and the decrease of the specific surface area resulted in the deactivation of the catalyst. 相似文献
2.
Tatsuro Tanaka Yoshifumi Maeda Shinji Yamamoto Toru Iwao 《Electrical Engineering in Japan》2019,207(1):15-23
The arc welding has been used in various welding methods because it is inexpensive and high in strength after welding. However, it is a problem that accidents such as collapse of the bridge occur because of the welding defects. The welding of low cost and high productivity is required without the welding defects. The pulsed TIG welding is inexpensive and capable of high‐quality welding. The electromagnetic force contributing to penetration changes because the transient response of arc temperature and iron vapor generated from anode occurs. However, the analysis of pulsed TIG welding with metal vapor has been elucidated only metal vapor concentration near anode with transient phenomenon and heat flux. Thus, the theoretical elucidation of penetration depth with control factor has not been researched. In this paper, the contribution of metal vapor mass at the periphery part of pulsed arc to the electromagnetic force in the weld pool is elucidated. As a result, the iron vapor mass at periphery part decreased with increasing the frequency. The iron vapor was stagnated at axial center within one cycle. The electromagnetic force to the penetration depth direction in weld pool increased at axial center. Therefore, the metal vapor mass at periphery part plays an important role for the electromagnetic force increment at axial center. 相似文献
3.
Tomonari Tanaka Ayane Matsuura Yuji Aso Hitomi Ohara 《Journal of Applied Glycoscience》2020,67(4):119
Glycopolymers have attracted increased attention as functional polymeric materials, and simple methods for synthesizing glycopolymers remain needed. This paper reports the aqueous one-pot and chemoenzymatic synthesis of four types of glycopolymers via two reactions: the β-galactosidase-catalyzed glycomonomer synthesis using 4,6-dimetoxy triazinyl β-D-galactopyranoside and hydroxy group-containing (meth)acrylamide and (meth)acrylate derivatives as the activated glycosyl donor substrate and as the glycomonomer precursors, respectively, followed by radical copolymerization of the resulting glycomonomer and excess glycomonomer precursor without isolating the glycomonomers. The resulting glycopolymers bearing galactose moieties exhibited specific and strong interactions with the lectin peanut agglutinin as glycoclusters. 相似文献
4.
Graded evolution of anisotropic microstructure during sintering from crystal-oriented powder compact
Shoko Baba Alexandre Maître Nicolas Pradeilles Guy Antou Nobuo Saito Satoshi Tanaka 《International Journal of Applied Ceramic Technology》2020,17(2):677-684
Anisotropic sintering, including shrinkage and grain growth, was examined for c-axis-oriented (Sr,Ca)2NaNb5O15 (SCNN) ceramics, which were prepared by colloidal processing under a magnetic field. In the c-axis-oriented SCNN powder compact, shrinkage and grain growth along the c-axis were higher than those along the a-axis. The anisotropic microstructural development was clearly associated with anisotropic sintering shrinkage. X-ray diffraction, scanning electron microscopy, and energy back scattering diffraction showed that the grain growth of oriented particles by including random grains contribute to the development of the oriented microstructure. Finally, the highly crystal-oriented SCNN ceramics with a densified microstructure were obtained through anisotropic sintering. These results clearly showed the potential to develop a well-defined anisotropic microstructure during sintering by designing and controlling the particle packing structure in a powder compact. 相似文献
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7.
NM Forones M Tanaka D Machado JB Falc?o M Giovanoni 《Canadian Metallurgical Quarterly》1997,34(1):3-6
Female SJL mice are more susceptible than male mice to experimental autoimmune encephalomyelitis (EAE) induced by myelin basic protein (MBP)-specific T lymphocytes. In the present study, we examined mechanisms involved in this gender-related difference in disease susceptibility. MBP-specific T lymphocytes derived from spleens of males during the effector phase of adoptive EAE produced significantly higher levels of IL-10, an anti-inflammatory cytokine in EAE. A protective effect of testosterone was then shown. Females implanted with dihydrotestosterone pellets demonstrated a significantly less severe course of EAE as compared with females implanted with placebo pellets. Finally, MBP-specific T lymphocytes derived from dihydrotestosterone-implanted females produced significantly higher levels of IL-10 than those from placebo. Together these data indicate that testosterone exerts a protective effect in EAE that is mediated at least in part by enhanced production of IL-10 by autoantigen-specific T lymphocytes. 相似文献
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9.
T Kimura H Yoshizu N Hatori M Shimizu D Segawa S Tanaka 《Canadian Metallurgical Quarterly》1997,45(4):607-610
A 60-year-old woman who complained of palpitation was diagnosed as ventricular tachycardia on electrocardiography and admitted to our hospital. The ultrasonic cardiography showed cardiac tumor in right ventricle and right atrium. Due to the obstruction of the right ventricle inflow by the tumor, we immediately performed resection of cardiac tumor and repair of right ventricle wall under cardiopulmonary bypass. The tumor was diagnosed as malignant lymphoma by pathological examination for surgical specimen of tumor. After operation her general condition was good, but residual cardiac lymphoma developed large size. We performed radiation therapy for cardiac lymphoma. Therefore the lymphoma was reduced to minimum size. Six months after operation metastatic malignant lymphoma appeared at whole body. So we performed chemotherapy for reduction of systemic malignant lymphoma. At first the chemotherapy was very effective. But metastasis spread rapidly and effectiveness of chemotherapy reduced. Thirteen months after operation she died for respiratory distress, probably due to metastatic brain tumor. 相似文献
10.
O Tanaka 《Canadian Metallurgical Quarterly》1997,59(4):155-165
BACKGROUND: Arrhythmias are frequent pathology in patients with chronic hemodialysis. We evaluated whether a relatively new technique, signal averaging, could be useful in predicting the development of complex arrhythmias in these patients. METHODS: Thirty-three patients, 18 male and 15 female, subjected to thrice weekly chronic hemodialytic treatment with various dialysis techniques, were studied. Exclusion criteria were the presence of antiarrhythmic and inotropic treatment. The following examinations were carried out in all patients: a Holter dynamic electrocardiography for a duration of 24 hours, begun on the day of dialysis, high resolution ECG pre- and post-dialysis to find out if there were any ventricular late potential (VLP). Four hundred beats were examined in order to obtain a background noise of less than 0.7 microV and a better definition of the signal. The following parameters were considered significant for the presence of VLP: a) filtered QRS duration > 120 msec; b) the root mean square of the signal expressed in the terminal portion of QRS (RMS) < 25 microV) high frequency low amplitude signals duration (HFLA) > 40 msec. A positive value in two of these parameters was considered indicative of the presence of VLP. In addition various pre and post-dialysis indices of dialytic efficiency and a mono and two-dimensional echocardiogram with pulsed and color Doppler were carried out. Of the 33 patients studied, ten were excluded because they presented too high a background noise at the high resolution ECG. Of the remaining 23 patients, 13 (56%) presented VLP and nine of these (69%) presented complex arrhythmias. Of the ten patients without VLP, 5 (50%) presented complex arrhythmias. The incidence of arrhythmias was highest during the last two hours of dialysis and in the two hours following it. The patients were then divided into two groups (A and B) according to the ejection fraction (EF) found at the echocardiogram. Group A was composed of 17 patients of whom 8 (47%) presented complex arrhythmias; group B (EF < 45%) was composed of the remaining six patients, who all presented complex arrhythmias. In group A nine patients (53%) out of 17 had LVP, in group B four out of six (66%) had it. All the patients except one presented an increase in the thickness of the ventricular wall and alterations of Doppler transmitral filling rate. Left ventricular hypertrophy was diagnosed in 22 out of the 23 patients. Four patients also had chronic ischaemic heart disease; of these three had LVP. There was no correlation between the presence of LVP and the hemodialytic indices and between the latter and complex arrhythmias. CONCLUSIONS: Our study showed that arrhythmias are more frequent in patients with LVP before dialysis than in those without. The difference was statistically significant (p < 0.006); the incidence of arrhythmias was higher in patients with FE < 45% (p < 0.001). The majority of patients (95%) had left ventricular hypertrophy; only four (17%) had ischaemic heart disease too. It is highly probable that the presence of LVP in our patients can be attributed to hypertension and subsequent left ventricular hypertrophy. As patients with LVP at the end of dialysis had a greater incidence of arrhythmias than those without LVP, we suggest that this method could be useful as a first screening in dialysed patients. 相似文献