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41.
A nondestructive inspection method for screening explosive materials that are hidden in passenger vehicles, trucks, and cargo containers with radiation shielding was presented. The method was examined experimentally using linearly polarized two-colored photon beam. A sample object was irradiated with the photon beam, followed by an emission of gamma-rays in nuclear resonance fluorescence. The gamma-rays from oxygen and nitrogen emitted through nuclear resonance fluorescence were measured using high-purity germanium detectors. We were able to evaluate the element concentration ratio.  相似文献   
42.
Synchrotron X-ray microtomography has been used for the three-dimensional characterization of microstructure in the cell walls of aluminum foams. A combination of high-resolution phase contrast imaging technique and several application techniques has enabled the quantitative image analyses of microstructures as well as the assessment of their effects on deformation behaviors. The application techniques include local area tomography, microstructural gauging and in-situ observation using a specially designed material test rig. It has been clarified that ductile buckling of a cell wall occurs regardless of any of the microstructural factors in the case of a pure aluminum foam, while rather brittle fracture of a cell wall is induced by the existence of coarse micropores and their distribution independently of the intermetallic particles and the grain boundary in the case of aluminum foams alloyed with Zn and Mg. It has also been confirmed that coarse TiH2 particles, which are a residual foaming agent added to alloy melts, remain intact during the deformation. When cooling rate during foaming is high, however, lower energy absorption might be attributable to the significant amount of residual TiH2 particle and its inhomogeneous distribution. These tendencies are also confirmed by three-dimensional strain mapping by tracking internal microstructural features.  相似文献   
43.
Kinetics of attached heterotrophic microbial growth was investigated experimentally using a continuous stirred tank reactor (121) for stream self-purification studies. Glucose was fed as the only source of carbon to the reactor in low concentration (4.5 27. mg-glucose l−1).Substrate consumption rate was dependent not on substrate concentration but on substrate loading. Oxygen consumption rate had a linear relationship with substrate consumption rate. The respiration rate of attached microbial population was 9 mgO2g−1 cell per hour.At steady state, attached growth rate was independent of substrate consumption rate because the attached growth was presumably suppressed by the limitation on attached surface area. Growth yield for substrate decreased with increasing substrate loading.  相似文献   
44.
Asai  Sumiko 《Scientometrics》2020,124(1):663-677
Scientometrics - Many academic societies and universities entrust the publication of their open access journals to large publishers, and this collaboration strengthens the presence of these...  相似文献   
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BACKGROUND/AIMS: The omentum is the site where peritoneal metastases occur most frequently. It has not been shown whether complete resection of the omenta during gastrectomy improves the survival of gastric cancer patients with macroscopic peritoneal metastases. METHODOLOGY: We retrospectively analyzed 126 patients who underwent gastrectomies for gastric cancer with peritoneal metastases but without hematogenous metastases. The 126 patients were stratified according to their grade of peritoneal metastases into three groups: the P1 patients (patients with peritoneal metastases in the adjacent peritoneum but not in the distant peritoneum); the P2 patients (patients with a few peritoneal metastases in the distant peritoneum); and the P3 patients (patients with many metastases in the distant peritoneum). In each group, the survival and clinicopathological characteristics were compared between patients treated by complete resection of the greater omentum and the lesser omentum plus extensive lymphadenectomy during gastrectomy, versus patients treated by incomplete resection of the omenta and non-extensive lymphadenectomy during gastrectomy. RESULTS: Complete omentectomy and extensive lymphadenectomy during gastrectomy improved survival significantly only in the P1 patients. Other clinicopathological characteristics did not differ between them. CONCLUSION: Complete omentectomy and extensive lymphadenectomy is recommended in patients with peritoneal metastases in the adjacent peritoneum but not in the distant peritoneum.  相似文献   
48.
Combined sewer overflows (CSOs) have been recognised as one of the serious sources of pollution to the water environment during rain events, although field surveys to investigate the effect of their magnitude and duration on receiving waters have been very limited. The fates of enteric viruses (norovirus G1, G2, enteroviruses) and coliforms were determined in the wastewater treatment plant on a fine day and on a rainy day. Not all microorganisms were reduced in the primary treatment, but were reduced in the secondary treatment. Occurrences of enteric viruses and levels of coliforms were surveyed in the receiving coastal area after a CSO event, with the profiles of the enteric viruses in the coastal seawater being almost at the same positive ratio for 4 d after the CSO event.  相似文献   
49.
Tuberculosis of the breast is a rare modern disease or a forgotten diagnosis. During the last 15 years (1982-1996), 28 cases of mammary tuberculosis were reported in Japan. The initial diagnosis of almost all were carcinoma. Physical sign, mammography and USG are not so usefull for the diagnosis. It is important for the early and certain diagnosis to detect acid-fast bacilli on smear or culture and to perform pathological examination on biopsied specimen.  相似文献   
50.
The seasonal profiles of microorganisms in raw sewage, secondary-treated sewage, and final effluent at a wastewater treatment plant in Tokyo, Japan, were quantitatively determined each month for one year, from July 2003 to June 2004. Human noroviruses, which were determined by real-time PCR, in raw sewage varied from 0.17-260 copies/mL for genotype 1 and from 2.4-1900 copies/mL for genotype 2, showing much higher values in winter, the epidemic season. The concentration of total coliforms, Escherichia coli, or F-specific phages in raw sewage was almost constant throughout the year. Human noroviruses of genotype 2 were removed most effectively (3.69 log10 on average) at the wastewater treatment plant, followed by E. coli (3.37 log10), total coliforms (3.05 loglo), F-specific phages (2.81 log10), and human noroviruses of genotype 1 (2.27 log10). The removal ratio of human noroviruses was almost constant, independent of the initial concentration of the viruses in raw sewage, which led to the increasing concentration of human noroviruses in final effluent in winter. None of the tested bacteria was judged to be a reliable indicator of human noroviruses in final effluent.  相似文献   
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