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101.
Numerical prediction of fraction of eutectic phase in Sn−Ag−Cu soldring using the phase-field method
Machiko Ode Minoru Ueshima Taichi Abe Hideyuki Murakami Hidehiro Onodera 《Journal of Electronic Materials》2006,35(11):1969-1974
A combination of macroscale solidification simulation and phase-field calculation is employed to predict the volume fraction
of the eutectic phase in Sn-4.0 mass% Ag-XCu solder alloys (X=0.5–1.1 mass%). The solidification simulation incorporates the
cooling rate in the phase-field simulation. We assume the residual liquid solidifies as eutectic phase when the driving force
for the nucleation of Cu6Sn5 amounts to a critical value, which is determined based on the experimental data. Though the calculation results depend on
the experimental data, the obtained fractions are about 40% for 0.5 mass% Cu and more than 90% for 1.1 mass% Cu alloy, which
shows good agreement with the experimental data. 相似文献
102.
A new process for electrolytic production of a perfluorinated compound, (CF3)3N, using lanthanum nickel oxide-coated Ni sheet anode in the (CH3)4NF·4.0HF melt at room temperature, was developed. Thin films of the lanthanum nickel oxides were prepared on Ni sheets by sol-gel coating method using polyvinlylpyrrolidone(PVP). The main components of the thin films were La2O3, LaNiO3, and La2NiO4 at 500, 750 and 1000 °C, respectively. The anode performance in the (CH3)4NF·4.0HF melt depends greatly on the main component of the thin film, and the LaNiO3-coated Ni sheet anode gives the best anode performance. The potential of LaNiO3-coated Ni sheet anode remains constant at 5.9 V during electrolysis at 20 mA·cm−2 in the (CH3)4NF·4.0HF melt for 100 h. This is because LaNiO3 and NiF3, and/or Ni2F5, the latter of which was formed during electrolysis, in the film give a high electronic conductivity to the surface film during electrolysis. The maximum mole fraction of (CF3)3N (21.4%) was obtained at 20 mA·cm−2 in (CH3)4NF·4.0HF melt using the LaNiO3-coated Ni sheet. 相似文献
103.
M Saito A Yamaguchi T Goi T Tsuchiyama G Nakagawara T Urano H Shiku K Furukawa 《Canadian Metallurgical Quarterly》1999,56(2):134-141
The strains BALB/cHeA (BALB/c) and STS/A (STS) differ in production of IL-4 and IL-10, two Th2 cytokines, after stimulation of spleen cells with Concanavalin A, STS being a low and BALB/c a high producer. We analyzed the genetic basis of this strain difference using the recombinant congenic (RC) strains of the BALB/c-c-STS/Dem (CcS/Dem) series. This series comprises 20 homozygous strains. Each CcS/Dem strain contains a different, random set of approximately 12. 5% genes of the "donor" strain STS and approximately 87.5% of the "background" strain BALB/c. We selected for further analysis the RC strain production intermediate between BALB/c and STS. In (CcS-20xBALB/c)F2 hybrids we found that different loci control expression of IL-4 and IL-10. Cypr1 (cytokine production 1) on chromosome 16 near D16Mit15 controls IL-4 production, whereas the production of IL-10 is influenced by loci Cypr2 near D1Mit14 and D1Mit227 on chromosome 1 and Cypr3 marked by D5Mit20 on chromosome 5. In addition, the relationship between the level of these two cytokines depends on the genotype of the F2 hybrids at a locus cora1 (correlation 1) on chromosome 5. This differential genetic regulation may be relevant for the understanding of biological effects of T-helper cells in mice of different genotypes. 相似文献
104.
Mobile catabolic genes in bacteria 总被引:6,自引:0,他引:6
The recent findings of various mobile catabolic genes have provided some insight into the evolution of microbial degradation systems for xenobiotic compounds. The catabolic genes undergo marked genetic rearrangements due to their presence on transposons or association with mobile genetic elements. Bacterial catabolic transposons fall into three defined structural classes. Class I elements include catabolic genes flanked by two copies of insertion sequences. Class II elements carry short terminal inverted repeats and transpose by the replicative mode in which transposase and resolvase are involved. Conjugative catabolic transposons represent the third class of mobile genetic elements. They carry all the genes required for excision, conjugal transfer to a new host, and integration. This review focuses on the structures, functions and roles of the recently characterized catabolic transposons in bacteria. Also described are the mobile catabolic elements that share structural similarity with the pathogenicity and symbiosis islands. 相似文献
105.
Iemura Y Yamada T Takahashi T Furukawa K Hara S 《Journal of Bioscience and Bioengineering》1999,88(3):276-280
In the supernatant of sokujo-moto, a high level of acid carboxypeptidase (ACP) activity and a large amount of peptides were observed, however, the amount of free amino acids liberated was small. In order to determine why these peptides were not hydrolyzed to any significant degree by the ACP, the properties of the peptides in sokujo-moto were investigated in this study. Peptides were fractionated from sokujo-moto by ion exchange column chromatography. ACP purified from rice-koji (rice overgrown with Aspergillus oryzae) was allowed to react with the peptides, and it was found that they were not hydrolyzed to any significant degree by the enzyme. Gel filtration chromatography was performed to ascertain the molecular size distribution of the peptides in sokujo-moto, and it was revealed that they were of low molecular sizes; molecular size: mainly in the range of 200-400, and chain length: 2-3. ACP purified from rice-koji was also allowed to react with various synthetic peptides, and it was found that ACP of rice-koji could not rapidly hydrolyze low-molecular-size peptides, such as dipeptides or tripeptides. Acid protease (AP) purified from rice-koji released peptides of molecular sizes mainly in the range of 300-600 or above from rice protein under acidic conditions (pH 3.6; the pH of sokujomoto). When AP and ACP were allowed to act at the same time on rice protein, mainly low-molecular-size peptides (molecular sizes mainly in the range of 200-400) were produced. From these results, it was estimated that AP released peptides with molecular sizes mainly in the range of 300-600 or above from rice protein and ACP degraded the relatively higher molecular size peptides among them to lower molecular size peptides; consequently only low-molecular-size peptides with molecular sizes mainly in the range of 200-400 were released in the supernatant of sokujo-moto. 相似文献
106.
T. Furukawa K. Noda T. Fujimoto T.H. Uesugi S. Shibuya M. Torikoshi 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2006,560(2):191-196
In order to define the optical parameters of a slowly extracted beam at the entrance of the extraction channel and to realize optical matching with the beam line, the outgoing separatrix was measured at HIMAC. Modifying the lattice parameters of the ring model according to the measurement result, the simulation result makes it possible to predict the optical parameters at the extraction channel. As a result, it was experimentally verified that optical matching of the slowly extracted beam with the transport line was realized. The measured beam size and dispersion functions were in good agreement with the calculation result at each monitor in the transport line. Particle tracking also predicts the beam profile at each profile monitor in the beam line. Further, a quasi-parallel beam was demonstrated by changing the beam optics in the beam line. 相似文献
107.
M Kameyama K Murata T Tsugawa T Yasuda H Nakano H Ohigashi M Hiratsuka Y Sasaki T Kabuto O Ishikawa H Furukawa S Imaoka 《Canadian Metallurgical Quarterly》1998,25(9):1385-1387
The aim of this study was to determine whether chemo-endocrine therapy after the resection of liver metastasis from colorectal cancer would prevent recurrence in the remnant liver and prolong survival. Eleven colorectal cancer patients underwent hepatic resection for liver metastasis. Subsequently, they were administered Proglumide gastrin antagonist 1,200 mg/day + 5'-DFUR 800 mg/day for 2 years. In seven of them, MMC 6-10 mg and ADM 20 mg were infused intra-arterially every two weeks alternately for one year. In four of them, 5-FU 250 mg/day was infused for seven days continuously intra-arterially every two weeks for one year. Recurrence in the remnant liver occurred in four of 11 patients. All of these patients underwent repeated hepatectomy. The mean disease-free survival in the remnant liver was 37 months and the five-year survival rate was 91%. These results indicate that intra-arterial chemotherapy with gastrin receptor antagonist might be effective for adjuvant therapy in patients with resectable liver metastasis from colorectal cancer. 相似文献
108.
109.
K Ohgi K Satoh S Tanaka T Higami T Furukawa H Akiyama S Kimura K Uehara K Murata M Higashi 《Canadian Metallurgical Quarterly》1998,56(11):2854-2858
Artifacts of MR cholangiopancreatography (MRCP) include fluid-filled gastrointestinal tracts, respiratory motion artifacts, spasm of Oddi's sphincter, vascular compression of bile ducts, overlapping of various anatomical structures and bright signal of surrounding fatty tissue. In this article, various technical considerations to eliminate these artifacts were described for the better imaging analysis of MRCP. The use of high-concentration ferric ammonium citrate (Ferriseltz) is recommended to reduce bright signal of fluid-filled gastrointestinal tracts. In case of long breathhold sequences, O2-inhalation study is useful to eliminate respiratory motion artifacts. Careful attention should be paid to the spasm of Oddi's sphincter and the vascular compression of bile ducts to avoid erroneous interpretation of MRCP findings. 相似文献
110.
H Furukawa T Kosuge K Shimada J Yamamoto Y Kanai K Mukai R Iwata K Ushio 《Canadian Metallurgical Quarterly》1998,133(7):735-739
We report the case of a 16-year-old girl who experienced sudden cardiac arrest from ventricular fibrillation, complicating an arrhythmogenic right ventricular dysplasia, a rare heart muscle disorder, occurring typically in young adults, characterized by a fibrofatty replacement of the right ventricular myocardium. Symptomatic ventricular arrhythmias are frequent, and sudden death has been reported. In our case, diagnosis of arrhythmogenic dysplasia was based on the association of one major criterion and two minor criteria as suggested by the relevant task force. In contrast with most other reports, the chest ECG did not display the typical features. An automatic transvenous pectoral cardioverter-defibrillator was implanted. The authors emphasise that juvenile forms are more exposed to ventricular fibrillation and sudden cardiac death, and consequently require the early detection of the disease. Family cases have been described and the occurrence in one individual must lead to investigations in the relatives. 相似文献