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521.
The nature of the high work‐hardening rate of nitrogen bearing steels was examined focusing on the stacking fault energy (SFE). The dislocation configuration and the width of dissociated dislocations were evaluated in various kinds of austenitic stainless steels with and without nitrogen, using the weak beam method. Nitrogen addition resulted in changing the dislocation configuration from tangled to planar. Nitrogen was, however, found to increase the SFE rather than decrease as reported previously and the SFE can be formulated as a function of chemical composition, SFE(mJ/m2) = 5.53 ‐ 0.16 (wt%Cr) + 1.40 (wt%Ni) + 17.10 (wt%%N). These results indicate that dislocation planarization by nitrogen addition is inadequately explained in terms of SFE. 相似文献
522.
H Yanagawa Y Nakamura T Ojima M Yashiro S Tanihara I Oki 《Canadian Metallurgical Quarterly》1999,18(1):64-66
Cholangiocarcinoma is the second most common primary tumor of the liver after hepatocellular carcinoma and accounts for 5 to 25% of primary hepatic malignancies. Patients with intrahepatic or peripheral cholangiocarcinoma (ICC) most often present at an advanced stage leading to a poor prognosis. A review of the literature has produced only 10 patients who have survived over five years. We review the case of a young woman with a large cholangiocarcinoma, who has been disease free for eight years. The patient was treated with a right hepatic lobectomy, and received 4 cycles of 5-fluorouracil and levamisole postoperatively. Known factors associated with longer survival in patients with ICC include lack of evidence of local invasion (i.e. capsular, lymphatic, or vascular), negative margins, mucoblia, and well differentiation of the tumor, as well as the absence of lymph node metastases. Our patient had negative margins and lymph nodes, and showed no local invasion. However, no mucobilia was noted, and the tumor was only moderately differentiated. Young age has never been associated with increased survival. ICC remains a relatively uncommon tumor with an insidious onset and late presentation contributing to poor survival. Surgical resection remains the only therapeutic option. Since few patients are potentially resectable at the time of presentation, efforts at early diagnosis and options for adjuvant therapy are imperative. 相似文献
523.
The paper is introducing an economic method (interindustry relations analysis) into studies of autopoietic systems and shows its application to scientometrics, which can also be regarded as the analysis of autopoietic systems. The merit of the application is discussed, and the outline of the proof of a related theorem is suggested in the appendix. 相似文献
524.
Effect of network-chain density (ν) on the strain-induced crystallization of peroxide-crosslinked natural rubber was studied by fast time-resolved synchrotron wide-angle X-ray diffraction. It was observed that the elongation ratio at the onset of strain-induced crystallization (αc) became smaller with the increase of ν. The difference of the entropy between the undeformed and deformed states at each αc was nearly equal in spite of the variation of ν. The calculated melting temperature at αc of the samples was also almost the same regardless of their ν. These observations mean that the strain-induced crystallization occurred when the deformation brought about a definite entropic state for peroxide-crosslinked natural rubber. They agreed with the prediction by Flory and were consistent with the classical theory of rubber elasticity. 相似文献
525.
Self-assembled fluorinated oligomeric aggregates formed by fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomers, N,N-dimethylacrylamide oligomers, and acrylic acid oligomers in methanol could recognize selectively fluoresceins as guest molecules
to form a new class of fluorinated aggregates/fluoresceins nanocomposites. These fluorinated fluoresceins nanocomposites were
found to exhibit an extraordinarily enhanced light absorption (λmax: ca. 440 nm) compared to that (λmaxs: 452 and 480 nm) of the parent fluorescein in the absence of fluorinated aggregates. On the other hand, fluoroalkyl end-capped
2-carboxyethyl acrylate oligomers, which possess no aggregate characteristic in methanol solutions, could not afford such
an enhanced light absorption peak under similar conditions. Not only fluorescein but also fluorescein derivatives such fluoresceinamine,
carboxyfluorescein, and fluorescein isothiocyanate afforded similar enhanced narrow absorption peaks under similar conditions.
Naphthofluorescein was also encapsulated into these fluorinated oligomeric aggregate cores to afford fluorinated aggregates/naphthofluorescein
composites, and these fluorinated naphthofluorescein composites afforded an extremely enhanced narrow absorption peak around
520 nm. 相似文献
526.
527.
Summary We successfully synthesized optically active polymer 4 by using chiral bisphosphine, (S,S)-1,2-bis(boranato(t-butyl)methylphosphino)ethane (S,S)-1, as a key building block. The structure of the polymer was characterized by 1H, 13C, and 31P NMR spectra. According to the CD spectra, the p-phenylene-ethynylene unit in the polymer main chain exhibited Cotton signals around the area of π-π* transition band. 相似文献
528.
Yuko Fujiwara Kotaro Hama Nobuyuki Shimozawa Kazuaki Yokoyama 《International journal of molecular sciences》2021,22(16)
Adrenoleukodystrophy (X-ALD) is an X-linked genetic disorder caused by mutation of the ATP-binding cassette subfamily D member 1 gene, which encodes the peroxisomal membrane protein, adrenoleukodystrophy protein (ALDP). ALDP is associated with the transport of very-long-chain fatty acids (VLCFAs; carbon chain length ≥ 24) into peroxisomes. Defective ALDP leads to the accumulation of saturated VLCFAs in plasma and tissues, which results in damage to myelin and the adrenal glands. Here, we profiled the glycosphingolipid (GSL) species in fibroblasts from X-ALD patients. Quantitative analysis was performed using liquid chromatography–electrospray ionization–tandem mass spectrometry with a chiral column in multiple reaction monitoring (MRM) mode. MRM transitions were designed to scan for precursor ions of long-chain bases to detect GSLs, neutral loss of hexose to detect hexosylceramide (HexCer), and precursor ions of phosphorylcholine to detect sphingomyelin (SM). Our results reveal that levels of C25 and C26-containing HexCer, Hex2Cer, NeuAc-Hex2Cer, NeuAc-HexNAc-Hex2Cer, Hex3Cer, HexNAc-Hex3Cer, and SM were elevated in fibroblasts from X-ALD patients. In conclusion, we precisely quantified SM and various GSLs in fibroblasts from X-ALD patients and determined structural information of the elevated VLCFA-containing GSLs. 相似文献
529.
Yoshito Suda Tomoaki Yoshikawa Yuko Okuda Mei Tsunemoto Yuri Matsuda Satoshi Tanaka Kazunori Ikeda Hitoshi Miyasaka Kazuo Harada Takeshi Bamba Kazumasa Hirata 《Journal of Bioscience and Bioengineering》2009,108(5):365-368
Comparative analysis was performed with a CFo ATP synthase subunit II homologue (CFo-II) derived from marine or fresh-water algae. The marine algae-derived CFo-II-transformed Escherichia coli grew and accumulated ATP more vigorously in NaCl or Cadmium containing medium, suggesting that this gene was useful for the development of stress-tolerant plant. 相似文献
530.
Y Toshima M Ojima H Yamada H Mori M Tonomura Y Hioki E Koya 《International journal of food microbiology》2001,68(1-2):83-91
People wash their hands only for a short time outside the home and when preparing meals at home. This may not be sufficient for those who prepare meals because of possible secondary contamination from food. Although washing with a placebo soap for a short period (lathering 3 s and rinsing 8 s) cleansed from hands about 95% of the total coliforms transferred from ground meat, an antibacterial soap further reduced the coliform count significantly (p < 0.01). To effectively avoid secondary contamination, it is recommended that people should more frequently wash their hands, using an antibacterial soap on the areas that have been in contact with raw meat, poultry, seafood, eggs, vegetables and other foods. 相似文献