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81.
K Nansai Y Kondo S Kagawa S Suh K Nakajima R Inaba S Tohno 《Environmental science & technology》2012,46(16):9146-9154
To build a life cycle assessment (LCA) database of Japanese products embracing their global supply chains in a manner requiring lower time and labor burdens, this study estimates the intensity of embodied global environmental burden for commodities produced in Japan. The intensity of embodied global environmental burden is a measure of the environmental burden generated globally by unit production of the commodity and can be used as life cycle inventory data in LCA. The calculation employs an input-output LCA method with a global link input-output model that defines a global system boundary grounded in a simplified multiregional input-output framework. As results, the intensities of embodied global environmental burden for 406 Japanese commodities are determined in terms of energy consumption, greenhouse-gas emissions (carbon dioxide, methane, nitrous oxide, perfluorocarbons, hydrofluorocarbons, sulfur hexafluoride, and their summation), and air-pollutant emissions (nitrogen oxide and sulfur oxide). The uncertainties in the intensities of embodied global environmental burden attributable to the simplified structure of the global link input-output model are quantified using Monte Carlo simulation. In addition, by analyzing the structure of the embodied global greenhouse-gas intensities we characterize Japanese commodities in the context of LCA embracing global supply chains. 相似文献
82.
Kagawa Y Mitani Y Yun HY Nakashima N Tamura N Tamura T 《Journal of Bioscience and Bioengineering》2012,113(5):596-603
The genus Rhodococcus exhibits a broad range of catalytic activity and is tolerant to various kinds of organic solvents. This property makes rhodococci suitable for use as a whole-cell catalyst. Various tools for genetic engineering have been developed to use Rhodococcus erythropolis as a host for bioconversion. In this study, we investigated the protein expression responses of R. erythropolis strains and found that isocitrate lyase production in R. erythropolis PR4 (ICL(Re)) was induced by methanol. By analyzing the regulation mechanisms of icl(Re) expression, the ~200-bp upstream region from the first nucleotide of the translation initiation codon of icl(Re) was shown to be sufficient for the methanol-inducible expression. Also, the ~100-bp upstream region exhibited strong constitutive promoter activity by an unknown mechanism(s). By investigating proteins that bound to the upstream region of icl(Re)in vitro, a RamB homologue of R. erythropolis PR4 (RamB(Re)) was identified. Moreover, 2 putative RamB(Re) binding sites were identified in the upstream region of icl(Re) through pull-down assays. A ramB(Re) knockout experiment suggested that RamB(Re) negatively controlled the expression of icl(Re) and that RamB(Re) regulation was dependent on the availability of a carbon source. On the basis of these findings, we were able to create novel methanol-inducible and strong constitutive expression vectors. 相似文献
83.
In this paper, the control design with distributed model of pipelines is proposed to make the cylinder side be free of pressure sensors. In this research, long connected pipelines are used. The pipeline is designed as a one dimensional distributed model. The model of pipelines is based on the discretization of four equations, as state equation of air, motion equation, continuity equation, and energy equation. The distributed model estimates the pressure losses and time delay through long connected pipelines in real time. To confirm the control method with distributed model of pipelines, a simulation model of the whole system is designed. Compared simulation and experimental results, it has been found that the model represents the real system well. In the experiments, the pressure values in the cylinder chambers estimated by the distributed model in real time played as control signals. Compared with the estimated and measured pressure values in the cylinder chambers, it is found that with this distributed model, the pressure values in the cylinder chambers is precisely estimated in real time using the measured values at the control ports of the servo valve. The experimental results demonstrate that the position accuracy is almost the same with that of using the measured pressure signals in the cylinder chambers. The cylinder side is free of pressure sensors with the proposed control method. 相似文献
84.
85.
Anodization is a useful technique for forming protective films on magnesium alloys and improves its corrosion resistance. Based on the alkaline electrolyte solution with primary oxysalt developed previously, the optimum secondary oxysalt was selected by comparing the anti-corrosion property of anodic film. The structure, component and surface morphology of anodic film and cross-section were analyzed using energy dispersion spectrometer (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The corrosion process was detected by electrochemical impedance spectroscopy (EIS). The results showed that secondary oxysalt addition resulted in different anodizing processes, sparking or non-sparking. Sodium silicate was the most favorable additive of electrolyte, in which anodic film with the strongest corrosion resistance was obtained. The effects of process parameters, such as silicate concentration, applied current density and temperature, were also investigated. High temperature did not improve anti-property of anodic film, while applying high current density resulted in more porous surface of film. 相似文献
86.
87.
88.
Keiji Hashimoto Yasuyuki Matsumura Masazumi Fukuchi Yoshiya Kera 《Catalysis Letters》1993,19(4):375-381
Heteropolyacid is introduced in an intercalation compound of zinc aluminum carbonate hydroxide by an anion-exchanging technique. The acid is probably present as H2.1PW9.2O4.2–
33.3 and is shown to be highly dispersed. The compound catalyzes dehydration ofn-butanol with noticeably higher activity and selectivity to 1-butene than free Keggin type 12-heteropolyacid. 相似文献
89.
The effect of the matrix–fibre interface bonding and debonding condition on the crack growth behaviour in a fibre-reinforced ceramic matrix composite was studied using a model glass fibre-reinforced PMMA matrix composite. The crack growth process from a centre notch is monitored using a compression splitting test. From direct observation three characteristic stages can be identified in the crack growth process of the composite, namely elastic constraint (stage I), matrix crack bowing (stage II) and crack bridging (stage III). Partial interface debonding occurs at the end of stage I and cylindrical interface debonding occurs at the end of stage II. The crack growth rate is accelerated just after the onset of interface partial debonding and this indicates that a debonded interface reduces the crack growth resistance. The partial interface debonding which occurs before fibre breaking plays an important role on the crack growth mechanism. 相似文献
90.
T Inoue T Inoue T Teshima S Murayama T Nose E Tanaka H Yamazaki M Koizumi K Kagawa S Ozeki H Ikeda 《Canadian Metallurgical Quarterly》1996,172(6):301-305
BACKGROUND/AIM: Late local recurrence after radiotherapy for tongue and early glottic carcinoma is rarely discussed. In the head and neck cancer, approximately 90% of local recurrence occurred within 2 years after radiotherapy. However, we found that late local recurrence after radiotherapy for glottic cancer was not rare. Our aim was to evaluate the late local recurrence after radiotherapy for early glottic and tongue cancer. PATIENTS AND METHODS: From 1967 through 1982, 633 patients with tongue carcinoma and 330 patients with early (T1T2N0) glottic carcinomas were treated at the Department of Radiology, Osaka University Hospital. Of these 821 patients, 329 patients with tongue carcinoma and 221 patients with early glottic carcinoma survived at 5 years after radiotherapy without local recurrence. For tongue carcinoma, patients were divided by T category. For early glottic carcinoma, patients were divided by the tumor response at 40 Gy. RESULTS: Late local recurrence occurred in 23 of 329 patients (7%) with tongue carcinoma, and in 9 of 221 (4%) with early glottic carcinoma. For tongue carcinoma, late recurrence occurred in 19 of 249 patients (8%) in stage I and II, and 4 of 80 patients (5%) in stage III and IV. For glottic carcinoma, late recurrence occurred in 8 of 137 patients (6%) with tumor clearance at 40 Gy and 1 of 63 patients (2%) with tumor persistence at 40 Gy. The incidence of double cancer was also evaluated. Of 329 5-year survivors with tongue carcinoma, 39 patients (12%) had another malignancy, and 26 patients of 221 5-year survivors with early glottic carcinoma (12%) had also another malignancy. Of 39 double primaries of tongue carcinoma, 10 patients (26%) had head and neck malignancies, and none of 26 double primaries of early glottic carcinoma. CONCLUSION: Late local recurrence was not rare in tongue and early glottic cancer. Poor prognostic group showed lower incidence of late recurrence than good prognostic group. This result suggests that secondary tumor at the same site of primary tumor is late local recurrence. 相似文献