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排序方式: 共有307条查询结果,搜索用时 46 毫秒
101.
The effect of thermal aging on microstructural changes was investigated in stainless steel weld-overlay cladding composed of 90% austenite and 10% δ-ferrite phases using atom probe tomography (APT). In as-received materials subjected to cooling process after post-welding heat treatments (PWHT), a slight fluctuation of the Cr concentration was already observed due to spinodal decomposition in the ferrite phase but not in the austenitic phase. Thermal aging at 400 °C for 10,000 h caused not only an increase in the amplitude of spinodal decomposition but also the precipitation of G phases with composition ratios of Ni:Si:Mn = 16:7:6 in the ferrite phase. The chemical compositions of M23C6 type carbides seemed to be formed at the austenite/ferrite interface were analyzed. The analyses of the magnitude of the spinodal decomposition and the hardness implied that the spinodal decomposition was the main cause of the hardening. 相似文献
102.
Zinc oxide that has the photocatalytic activity is used as a white pigment for cosmetics. A certain degree of sebum on the skin is decomposed by the ultraviolet radiation in sunlight. In this work, zinc phosphates were prepared from zinc nitrate and phosphoric acid at pH 5 and 7 with and without the addition of sodium lactate and ultrasonic treatment as a novel white pigment for use in cosmetics. The chemical composition, powder properties, photocatalytic activity, colour phase, moisture retention and smoothness of the zinc phosphates were studied. The obtained materials had a Zn/P ratio of about 1.5, which corresponds to zinc orthophosphate Zn3(PO4)2. Samples prepared with ultrasonic treatment indicated the high ratios of large particles in scanning electron microscopy images and particle‐size distributions. The photocatalytic activity of these zinc phosphate particles was too less to protect the sebum on the skin. The materials obtained and their thermal products at 100°C showed a high reflectance within the range of visible light. The slipping resistance and roughness of the powder were enough low for use in cosmetics. 相似文献
103.
MF Farah M One JC Novello MH Toyama J Perales H Moussatché GB Domont B Oliveira S Marangoni 《Canadian Metallurgical Quarterly》1996,34(9):1067-1071
The fractionation of Didelphis albiventris serum by DEAE-Sephadex A50 yields a fraction (DA2) which protects the opossum against Bothrops venom. One polypeptide (DA2-II) responsible for this protection was isolated from fraction DA2 by ion exchange chromatography and biochemically characterized. DA2-II is a 43,000 mol. wt glycoprotein with the following N-terminal sequence: LKAMDTTPPLKIKKEPVK. Pairwise comparison of the amino acid sequence with four anti-hemorrhagic factors isolated from other opossum species indicated that DA2-II possesses high similarity (60-80%) with these proteins. 相似文献
104.
The number of deep mycosis has been increasing because of increases in immunocompromised hosts and in fungal colonization associated with increasing use of broad-spectrum antibacterial antibiotics. Based on these phenomenon, a simple test method for an early diagnosis of deep mycosis is urgently desired. We therefore investigated the usefulness of assaying a fungal cell component, (1-->3)-beta-D-glucan (beta-glucan). The amount of beta-glucan was obtained from the difference between the amounts determined using Toxicolor and Endospecy, and the serum levels of more than 10 pg/ml were considered positive signs for beta-glucan. The following results were obtained: We found that beta-glucan was positive in 75% of the patients who had been definitely diagnosed to have mycosis, and in 58.3% of the patients strongly suspected of mycosis. The numbers of beta-glucan positive patients' in these 2 groups of patients were significantly different from that in those without mycosis (14.7%, P < 0.05). Thus a usefulness of beta-glucan measurement for the diagnosis of mycosis was demonstrated. However, beta-glucan was sometimes negative even in patients with fungemia at an early phase of the disease and turned positive several days later. Even in a patient with definite lung mycosis, who had a latent circumscribed lesion (afebrile and CRP-negative), beta-glucan was also negative. From these findings, one should be aware that the beta-glucan test produces false negatives even in patients with definite mycosis and that the test should be repeated during the course of the disease. 相似文献
105.
MH Toyama AM Soares CA Vieira JC Novello B Oliveira JR Giglio S Marangoni 《Canadian Metallurgical Quarterly》1998,17(7):713-718
OBJECTIVE: To investigate possible differences in cytomegalovirus (CMV) strain distribution between the eye and blood in AIDS patients with CMV retinitis. METHODS: CMV DNA sequences from aqueous humour and peripheral blood leukocytes (PBL), obtained from 13 AIDS patients with CMV retinitis, were compared. DNA was isolated and the CMV IE-1 sequence (part of the immediate early-1 gene) and the a-sequence (located in the a-region) were amplified by polymerase chain reaction (PCR). The PCR products of the a-sequence were analysed by Southern blotting for amplified fragment-length polymorphisms. The level of divergence between the a-sequences of aqueous humour- and PBL-derived CMV was studied in two patients by cloning these sequences followed by sequence analysis. RESULTS: CMV DNA could be detected in all aqueous humour samples and in 10 out of 13 paired blood samples. In the 10 patients, with CMV DNA detectable in both aqueous humour and PBL, seven cases showed differences between the amplified products of both compartments. Sequence analysis in two patients revealed that the aqueous humour and PBL of the same patient can harbour both identical, similar and highly divergent CMV a-sequences. CONCLUSION: These results indicate that despite the haematogenous spread of CMV, the eye, being a relatively shielded organ, may contain CMV strains different from those found in the blood. 相似文献
106.
I Kasuga D Miyamoto Y Ichinose W Chimangul K Minemura K Utsumi M Yonemaru H Serizawa Y Ebihara K Toyama 《Canadian Metallurgical Quarterly》1998,11(5):1185-1187
We describe a rare case of pulmonary blastoma complicated with systemic sclerosis. The serum alpha-fetoprotein level was elevated at presentation and the biopsied tumour stained positively against anti-alpha-fetoprotein antibody. The alpha-fetoprotein produced autonomously by tumour cells was of yolk-sac origin. Although the pathogenesis of pulmonary blastoma has not been clarified, we suggest that this pulmonary blastoma is a type of yolk-sac tumour. 相似文献
107.
I Kasuga M Yonemaru H Kiyokawa Y Ichinose K Toyama 《Canadian Metallurgical Quarterly》1996,1(4):277-281
Type IV collagen is one of the major components of the basement membrane (BM). 7S domain (7S collagen) of type IV collagen is an N-terminal peptide which is stable against protease and heat. We investigated serum concentration of 7S collagen in patients with idiopathic pulmonary fibrosis (IPF) and other pulmonary diseases. The aim of this study was to evaluate whether changes in the serum concentration of 7S collagen reflect the fibrotic process of IPF. We measured the concentration of serum 7S collagen with radioimmunoassay in patients with IPF, chronic pulmonary emphysema (CPE), sarcoidosis, infectious pulmonary diseases (IPD) and normal healthy controls. We also monitored 7S collagen during the clinical course in some patients with IPF and investigated the correlation between the serum 7S collagen, and lactate dehydrogenase (LDH) and erthrocyte sedimentation rate (ESR) in patients with IPF. Patients with IPF showed significantly higher serum concentration of 7S collagen than other pulmonary diseases and healthy controls. The serum concentration of 7S collagen significantly decreased in IPF patients who showed roentgenographic improvement after corticosteroid treatment. There was a correlation between the serum 7S collagen and LDH, and ESR. In conclusion, serum concentrations of 7S collagen increase in patients with IPF. The measurement of 7S collagen is useful for the evaluation of fibrotic change in the lung. 相似文献
108.
Kengo Matsune Hiroyuki Oda Toshihiko Toyama Hiroaki Okamoto Yuriy Kudriavysevand Ren Asomoza 《Solar Energy Materials & Solar Cells》2006,90(18-19):3108-3114
For improving the photovoltaic performance of CdS/CdTe thin film solar cells, the CdS window layer is one of the most crucial factors. Here we demonstrate the photovoltaic performances of the low-environmental-load CdS/CdTe solar cell employing the CdS layer doped with various metal organic (MO) compounds, i.e., (CH3)2SnCl2, (C6H5)3GeCl, (CH3CO2)3In, [(C2H5)2NCS2]2Zn. Due to the MO doping, the degree of (1 1 1) preferential orientation of CdTe on the CdS layer is improved remarkably, influencing the increases in Voc and F.F. Being almost independent of the kind of the MO compounds, the short circuit current increases due to increasing optical transmittance of the MO-doped CdS layers. As a result, utilizing MO-doped CdS, we have achieved the conversion efficiency of 15.1%. 相似文献
109.
110.
Kusakari Keiichirou Nakamura Masaki Toyama Yoshihito 《Journal of Automated Reasoning》2006,37(3):205-229
To simplify the task of proving termination and AC-termination of term rewriting systems, elimination transformations have
been vigorously studied since the 1990s. Dummy elimination, distribution elimination, general dummy elimination, and improved
general dummy elimination are examples of elimination transformations. In this paper we clarify the essence of elimination
transformations based on the notion of dependency pairs. We first present a theorem that gives a general and essential property
for elimination transformations, making them sound with AC-termination. Based on the theorem, we design an elimination transformation
called the argument filtering transformation. Next, we clarify the relation among various elimination transformations by comparing
them with a corresponding restricted argument filtering transformation. Finally, we compare the AC-dependency pair method
with the argument filtering transformation.
Parts of this work were done while K. Kusakari was completing his Ph.D. thesis, “Termination, AC-Termination and Dependence
Pairs of Term Rewriting Systems,” at Japan Advanced Institute of Science and Technology, School of Information Science (March,
2000). A preliminary version of parts of this article appeared in K. Kusakari, M. Nakamura, Y. Toyama, Argument filtering
transformation, Proc. of Int. Conf. on Principles and Practice of Declarative Programming, LNCS 1702 (Springer-Verlag, 1999)
pp.47–61. 相似文献