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91.
Toshio Tanaka Shigeki Suzuki Yoshitsugu Nekomoto Mamoru Tanaka 《Nuclear Engineering and Design》1994,147(3)
This paper deals with a diagnostic and monitoring system for assessing the integrity of pipe branches, during the operation of the nuclear power plant. This system have been developed under the concept of “easy to use without any sophisticated analysis” and “portable”. The accuracy of the diagnosis is based on the model optimization subsystem, which automatically modifies the numerical vibration model so as to fit its natural frequency to the actual natural frequency. The information obtained by this system may be reflected to a maintenance program of the plant to assure more reliable operation of the plant. 相似文献
92.
Jiwang Yan Takuya Kaneko Kazunori Uchida Nobuhito Yoshihara Tsunemoto Kuriyagawa 《The International Journal of Advanced Manufacturing Technology》2010,50(9-12):991-1002
A two-step electrodischarge machining method was proposed for fabricating microgrooves with varied cross-sections on hard materials. Firstly, tungsten tool electrodes were shaped by wire electrodischarge grinding, and then the resulting tool electrodes were used to electrodischarge machine microgrooves on stainless steel. Preliminary experimental results showed that, in the first step, a sharp tool electrode with surface roughness of 0.3 µmRa could be achieved, and the surface roughness of the resulting groove was 0.16 µmRa in the second step. Voltage strongly affects the machining speed. A high voltage (>70 V) was preferable for improving the material removal rate. However, significant tool wear took place when using a high condenser capacitance at high voltages. To suppress tool wear, a high voltage and a small capacitance should be used. As test pieces, microgrooves having rectangular, triangular, circular and semi-closed cross-sections were fabricated. 相似文献
93.
Video Scene Annotation Based on Web Social Activities 总被引:1,自引:0,他引:1
This article describes a mechanism to acquire the semantics of video content from the activities of Web communities that use a bulletin-board system and weblog tools to discuss video scenes. 相似文献
94.
We varied the promoter strength of xylose reductase (XR) gene and the copy number of xylulokinase (XK) gene to determine how XR and XK activities affect the xylose-fermenting abilities of recombinant Saccharomyces cerevisiae expressing xylitol dehydrogenase (XDH). The most enhanced ethanol yield and lowered xylitol yield occurred in strain I-PGK/AUR, which has high activity of both XR and XDH and moderate XK activity. 相似文献
95.
Acremonium cellulolyticus is a fungus that produces cellulase and has been exploited by enzyme industry. To promote cellulase production by A. cellulolyticus strain C-1, we evaluated the effects of the saccharides: Solka Floc (cellulose), soluble soybean polysaccharide (SSPS), pullulan, lactose, trehalose, sophorose, cellobiose, galactose, sorbose, lactobionic acid, and mixtures as carbon sources for cellulase production. Solka Floc with SSPS enhanced cellulase production. Lactose as the sole carbon source induced cellulase synthesis in this fungus, and the synergistic effects between lactose and Solka Floc was observed. Various enzyme activities and the protein composition of crude enzyme produced by cultures with or without addition of lactose were analyzed. The results showed that lactose addition greatly improves the production of various proteins with cellulase activity by A. cellulolyticus. To our knowledge, this is the first report on production of cellulases by lactose in the A. cellulolyticus. 相似文献
96.
Kazushi Shibutani Jun Nakai Ketkanok Aphichartsuphapkhajorn Yoshihito Kayaki Shigeki Kuwata Yoshihiko Arao Masatoshi Kubouchi 《应用聚合物科学杂志》2021,138(17):50311
The effect of oxygen and additional oxygen providers on furfuryl alcohol polymerization was investigated through chemical analyses and mechanical evaluation. NMR, UV–vis, Fourier transform infrared, and gas chromatography–mass spectrometry (GC–MS) results suggested that atmospheric oxygen and the further addition of an oxygen source functioned as an activator for the entire network polymerization. Interestingly, the construction of a conjugated structure on the furan linear chain, which is key to three-dimensional cross-linking, also appears to be accelerated in the presence of oxygen. Furthermore, the introduction of oxygen providers into the curing system successfully enhanced the mechanical properties of the cured furan resin. 相似文献
97.
T Ishidate S Yoshihara Y Kawasaki BC Roy K Toyoshima T Akiyama 《Canadian Metallurgical Quarterly》1997,409(2):237-241
Landmarks in the development of treatment of retinal detachment include the recognition of the significance of retinal breaks that resulted in the distinction between rhegmatogenous retinal detachment (RRD) and exudative retinal detachment, the development of indirect ophthalmoscopy and scleral depression that allow better visualization of the peripheral area of the retina and better identification of retinal breaks, the recognition of the need to seal all retinal breaks, and the realization that vitreous traction is the major underlying cause of retinal tears and RRD. Scleral buckling procedures combine retinopexy to provide a scar around retinal breaks to seal them and scleral indentation to neutralize vitreous traction; they provided the first effective treatment of RRD. As surgeons gained experience with scleral buckling, they became aware that some RRDs, particularly those with fixed folds and/or a funnel configuration, often could not be repaired using this approach. It was thought that excessive vitreous traction was at fault, and the condition was called "massive vitreous retraction." 相似文献
98.
We investigate the stability limits of linear stochastic human controller model. In our previous study, we had proposed a model by which the probability distributions of human visuomotor tracking data can be accurately reproduced. In this study, we conduct a stochastic analysis on our model by deriving a system of moment differential equations with respect to random state variables of this model. We evaluate the stability limits of our model by detecting zero-eigenvalue conditions of the Jacobian matrix of the moment differential equations. The resulting stability limits make it possible to characterize the human parameter values that were experimentally identified from the human participants in our previous study; this shows that during the visuomotor tracking experiments, the human participants generated huge fluctuations far from the stability limits while applying almost neutrally stable proportional gain. 相似文献
99.
Oishi M Nagatsugi F Sasaki S Nagasaki Y Kataoka K 《Chembiochem : a European journal of chemical biology》2005,6(4):718-725
A novel pH-sensitive and targetable antisense ODN delivery system based on multimolecular assembly into polyion complex (PIC) micelles of poly(L-lysine) (PLL) and a lactosylated poly(ethylene glycol)-antisense ODN conjugate (Lac-PEG-ODN) containing an acid-labile linkage (beta-propionate) between the PEG and ODN segments has been developed. The PIC micelles thus prepared had clustered lactose moieties on their peripheries and achieved a significant antisense effect against luciferase gene expression in HuH-7 cells (hepatoma cells), far more efficiently than that produced by the nonmicelle systems (ODN and Lac-PEG-ODN) alone, as well as by the lactose-free PIC micelle. In line with this pronounced antisense effect, the lactosylated PIC micelles showed better uptake than the lactose-free PIC micelles into HuH-7 cells; this suggested the involvement of an asialoglycoprotein (ASGP) receptor-mediated endocytosis process. Furthermore, a significant decrease in the antisense effect (27 % inhibition) was observed for a lactosylated PIC micelle without an acid-labile linkage (thiomaleimide linkage); this suggested the release of the active (free) antisense ODN molecules into the cellular interior in response to the pH decrease in the endosomal compartment is a key process in the antisense effect. Use of branched poly(ethylenimine) (B-PEI) instead of the PLL for PIC micellization led to a substantial decrease in the antisense effect, probably due to the buffer effect of the B-PEI in the endosome compartment, preventing the cleavage of the acid-labile linkage in the conjugate. The approach reported here is expected to be useful for the construction of smart intracellular delivery systems for antisense ODNs with therapeutic value. 相似文献
100.
The leaching behavior of heat-treated waste ash was studied to verify the possibility of the thermal treatment of waste incineration ash in existing incinerators and boiler combustion chambers. The influence of temperature, oxygen concentration and treatment time on the leaching behaviors of harmful heavy metals, especially lead (Pb) and chromium(VI) (Cr (VI)) were studied to clarify effective treatment conditions to suppress leaching. By examining the leaching behavior of Pb and Cr from ash heat-treated under various conditions, it was found that leaching can be suppressed by heat-treating the ash under conventional combustion conditions of around 900-1000 °C at 5-10% oxygen concentration. The leaching behaviors of Pb and Cr (VI) from real ash with different particle sizes and from model samples were also investigated in detail to find an effective method to suppress Pb leaching. It was found that the formation and growth of gehlenite (SiO2·2CaO·Al2O3) in the ashes led to the decrease in the amount of Pb leaching. Therefore it was considered that the addition of an inorganic matrix with a high silica content that can promote gehlenite growth in the ash, for example, coal ash or waste glass is effective to suppress of Pb leaching. 相似文献