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61.
Hirano K. Okamura J. Taira T. Sano K. Toyoda A. Ikeda M. 《Semiconductor Manufacturing, IEEE Transactions on》2001,14(3):202-206
Developers used in photolithography contain toxic tetramethylammoniumhydroxide (TMAH) and this creates a problem of how to properly treat developer wastewater. We have developed a TMAH wastewater treatment technique that consists of a combination of two novel decomposition processes: pyrolyzing TMAH to TMA and decomposing TMA to N 2, H2O, and CO2 by means of a selective oxidation catalyst for nitrogenous compounds. We have tested a system using this technique in long-term treatment of the actual wastewater and have found it to be sufficiently practical. The running cost of a treatment system using our technique would be about one-ninth that of disposing of the wastewater as industrial waste but about 2.3 times that of biological treatment. Compared with biological treatment, however, our system is tolerant to many treatment conditions and operation management is much easier. Furthermore, it occupies only about one-sixth the area of a biological treatment system 相似文献
62.
HW Yoon MC Kim PG Shin JS Kim CY Kim SY Lee I Hwang JD Bahk JC Hong C Han MJ Cho 《Canadian Metallurgical Quarterly》1997,255(4):359-371
Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses. 相似文献
63.
Both theory and studies on models predict that cracks extend stably form flaws in brittle materials subjected to compression. Once cracks have originated and extended, the tensile strength transverse to the cracks should be reduced. Tests on siliconized carbide verify this prediction; however, tests on hot-pressed silicon nitride refute it. Possible morphologies of the inherent flaws are speculated. 相似文献
64.
TR Kim Y Goto N Hirota K Kuwata H Denton SY Wu L Sawyer CA Batt 《Canadian Metallurgical Quarterly》1997,10(11):1339-1345
Bovine beta-lactoglobulin (BLG) variant A has been expressed in the methylotropic yeast Pichia pastoris by fusion of the cDNA to the sequence coding for the alpha-mating factor prepro-leader peptide from Saccharomyces cerevisiae. P. pastoris Mut+ transformants were obtained by single cross-over integration of the BLG-containing vector into the AOX1 locus. In a fed-batch fermenter, a cell density of approximately 300 mg/ml was achieved by controlled glycerol feeding for a total of 24 h. After 72 h of methanol induction, the secreted BLG reached levels of > 1 g/l. The secreted protein could be purified to homogeneity by ion-exchange chromatography. Amino-terminal sequencing of the secreted BLG revealed that the Glu-Ala spacer repeats inserted between the mature protein and the alpha-factor prepro-leader were still present. The purified protein was characterized by a number of methods, including CD spectroscopy, guanidine-HCl unfolding, crystallization and two-dimensional 1H-NMR spectroscopy. By all of these measures, the physical characteristics of recombinant BLG were indistinguishable from those of the native purified bovine BLG, making it useful as a model for protein folding and other biophysical studies. 相似文献
65.
66.
K Tanaka H Toyohira R Murata H Shibuya S Shimokawa N Hamada A Taira 《Canadian Metallurgical Quarterly》1997,48(9):833-838
This report describes a patient with Budd-Chiari syndrome who was operated on successfully by means of shunt formation with polytetrafluoroethylene graft between the inferior vena cava (IVC) and right atrium. The patient is a sixty-two-year-old woman suffering from persistent edema of the lower limbs for four years. The examination disclosed complete obstruction of the IVC at the level of the diaphragm with a patent right inferior hepatic vein. Following the operation, edema of the limbs disappeared, hypersplenism improved, and the serum ammonium concentration decreased to the normal range. In conclusion, a retrohepatic cavoatrial shunt is feasible and useful in treating a patient with the Budd-Chiari syndrome who has patent major hepatic veins. 相似文献
67.
68.
Fukuchi Y. Sakamoto T. Taira K. Kikuchi K. Kunimatsu D. Suzuki A. Ito H. 《Photonics Technology Letters, IEEE》2002,14(9):1267-1269
In all-optical gate switches that employ the cascaded second-order nonlinear effect in quasi-phase-matched (QPM) LiNbO/sub 3/ devices, walkoff between the fundamental and second harmonic pulses is very large. The authors experimentally show that crosstalk of the switch induced by such walkoff limits the switching speed, but that the switching speed can significantly be enhanced by walkoff compensation. Using a 20-mm-long QPM LiNbO/sub 3/ waveguide device, the authors switch one of twin pulses separated by 6.25 ps without crosstalk, showing the possibility of switching a 160-Gb/s signal. 相似文献
69.
Various four-base codons have been shown to work for the introduction of non-natural amino acids into proteins in an Escherichia coli cell-free translation system. Here, a four-base codon-mediated non-natural mutagenesis was applied to a eukaryotic rabbit reticulocyte cell-free translation system. Mutated streptavidin mRNAs containing four-base codons were prepared and added to a rabbit reticulocyte lysate in the presence of tRNAs that were aminoacylated with a non-natural amino acid and had the corresponding four-base anticodons. A Western blot analysis of translation products indicated that the four-base codons CGGU, CGCU, CCCU, CUCU, CUAU, and GGGU were efficiently decoded by the aminoacyl-tRNAs having the corresponding four-base anticodons. In contrast, the four-base codons AGGU, AGAU, CGAU, UUGU, UCGU, and ACGU were not decoded. The stop codon-derived four-base codons UAGU, UAAU, and UGAU were found to be inefficient, whereas the amber codon UAG and opal codon UGA were efficient for the incorporation of non-natural amino acids. The application of the expanded genetic code in a eukaryotic cell-free system opens the possibility of a four-base codon-mediated incorporation of non-natural amino acids into proteins in living eukaryotic cells. 相似文献
70.
JK Han HJ Jang BI Choi SH Kim TK Kim HJ Won YI Kim SY Cho 《Canadian Metallurgical Quarterly》1999,34(2):99-108
RATIONALE AND OBJECTIVES: The authors sought to correlate the radiologic findings of hepatobiliary fascioliasis with pathologic features. METHODS: Serial ultrasound, computed tomography (CT), and magnetic resonance findings in seven rabbits with experimentally induced fascioliasis were obtained every other week. Direct cholangiogram was also obtained after the rabbits were killed. Radiology-pathology correlation was done in specimens. RESULTS: In the parenchymal phase (an acute phase of parenchymal invasion of a larva), CT showed subcapsular clustered areas of low attenuation. Magnetic resonance appearance was similar in shape but better than CT in characterizing the hemorrhagic nature of the lesion. Ultrasound findings were nonspecific in this phase. In the ductal phase (a stationary phase after residing in the bile duct), CT showed dilatation of central ducts with symmetric periportal hypoattenuation (periportal tracking). Magnetic resonance could not depict mild ductal dilatation. Ultrasound was most valuable in demonstrating the moving worm within the dilated duct. Pathologically, the hepatic parenchymal lesions consisted of a cluster of eosinophilic granulomas with hemorrhagic change (migratory tract of the flukes). Ductal changes were observed predominantly in the central bile ducts. Periportal lymphangiectasia was also noted. CONCLUSIONS: Computed tomography or magnetic resonance can demonstrate the characteristic evolutionary pattern of fascioliasis that reflects the unique life cycle of Fasciola hepatica. The role of ultrasound, although limited in the parenchymal phase, was most useful in the ductal phase in that it demonstrated the moving worms themselves. 相似文献