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71.
K Uozumi N Ohno K Nakahara T Makino A Utsunomiya S Hanada T Arima 《Canadian Metallurgical Quarterly》1997,77(2):204-210
Differences in the responses of an elderly biracial group of cognitively normal subjects to a 15-item short version of the Boston Naming Test developed for the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) were examined. The subjects consisted of 103 Whites and 136 African Americans who were 70 years of age and older and living in a five-county urban and rural area of North Carolina. They were drawn from the Duke University site of the Established Populations for Epidemiologic Studies of the Elderly (EPESE). All were cognitively normal. With gender, years of education, and age controlled, White subjects performed significantly better than did African American subjects. The items in this test were selected to represent words with a high, medium, and low frequency of occurrence in English. They did not, however, show the expected gradation for either racial group. Medium and low frequency items were of comparable difficulty for the two races. Hierarchical ordering of difficulty would be improved with minor rearrangement of items. 相似文献
72.
Nakahara K. Tsuchiya T. Kitatani T. Shinoda K. Kikawa T. Hamano F. Fujisaki S. Taniguchi T. Nomoto E. Sawada M. Yuasa T. 《Lightwave Technology, Journal of》2004,22(1):159-165
Direct modulation at 12.5 Gb/s of 1.3-/spl mu/m InGaAlAs distributed feedback (DFB) ridge waveguide (RWG) lasers with low-resistance notch-free gratings running up to 115/spl deg/C is experimentally demonstrated. It was achieved by the combination of the high differential gain of an InGaAlAs MQW active layer, high characteristic temperature of RWG structure, and low-resistance notch-free grating. Moreover, successful transmission of 10-Gb/s modulated signals over 30-km standard single-mode fiber was achieved with the laser running at up to 115/spl deg/C. These results confirm the suitability of this type of laser for use as the cost-effective light source in 12.5-Gb/s and 10-Gb/s datacom applications. 相似文献
73.
Encapsulation of lead-free Sn/Zn/Bi solder alloy particles by coating with wax powder for improving oxidation resistance 总被引:2,自引:0,他引:2
Tomohiro Iwasaki Jeong Hwan Kim Shohei Mizuhashi Munetake Satoh 《Journal of Electronic Materials》2005,34(5):647-654
An encapsulation treatment of lead-free Sn/Zn/Bi solder powder was investigated for improving the oxidation resistance. Sn-8mass%Zn-3mass%Bi
alloy particles were coated with a wax (12-hydroxystearic acid) powder by means of a dry mechanical treatment method using
a ball mill. In order to determine the optimum operating conditions of the ball mill in the wax-coating treatments, the compressive
energy required for deforming a single Sn/Zn/Bi alloy particle was measured with an unconfined compression tester and the
mechanical energy applied to the alloy particles in the ball mill was estimated using the results of the compression test.
The optimum operating conditions were determined based on both the applied energy and the flowability of solder pastes, and
the wax-coated alloy particles maintaining the spherical shape were obtained under the conditions. The wettability test and
the solder balling test for the solder pastes containing the wax-coated alloy particles stored at room temperature in air
were carried out to evaluate the oxidation resistance performance. The wax-coated alloy particles had an excellent wettability
compared with the original alloy particles, and the oxidation resistance of the Sn/Zn/Bi solder powder was improved by the
encapsulation treatment. 相似文献
74.
75.
Mitsuyoshi Ishikawa Shohei Yamamura Yuzuru Takamura Koji Sode Eiichi Tamiya Masamitsu Tomiyama 《International Journal of Hydrogen Energy》2006
The development of a compact high-density microbial reactor for hydrogen production is described with possible implications to use as a portable bio-fuel cell system. To construct the compact bioreactor, mainly, the cell density and immobilization methods were optimized in this paper. The encapsulation of hydrogen producing bacterium, Escherichia coli strain MC13-4, in alginate gel beads provided approximately three-fold increase in hydrogen production in comparison with the free cell suspension. The immobilized cells (cell density; O.D. 100) and 500 mM glucose solution were packed into a 20 mL glass bottle that was connected to the fuel cell. This system has generated electricity of over 20 mW for 20 min. 相似文献
76.
A technique is presented for realistic rendering in polygon-based computer-generated holograms (CGHs). In this technique, the spatial spectrum of the reflected light is modified to imitate specular reflection. The spectral envelopes of the reflected light are fitted to a spectral shape based on the Phong reflection model used in computer graphics. The technique features fast computation of the field of objects, composed of many specular polygons, and is applicable to creating high-definition CGHs with several billions of pixels. An actual high-definition CGH is created using the proposed technique and is demonstrated for verification of the optical reconstruction of specular surfaces. 相似文献
77.
Warat Kongkitkul Shohei Kawabe Fumio Tatsuoka Daiki Hirakawa 《Soils and Foundations》2011,51(1):11-30
A simple but automated pneumatic loading system that can control the stress and strain rates for one-dimensional (1D) compression of clay was developed. The rate-dependency of stress-strain behaviour due to the viscous property of clay was investigated by 1D compression tests on standard-size specimens by various loading methods: 1) Standard Consolidation Tests (SCTs), stepwise increasing the axial stress two times every one day; 2) ordinary Constant-Rate-of-Strain (CRS) tests at different strain rates; 3) special CRS tests including unloading and reloading cycles with different stress amplitudes at strain rates of which the absolute value was either kept constant throughout respective tests or changed at the start of reloading; and 4) special CRS tests including a number of sustained loading (SL) during otherwise primary loading or unloading or reloading at constant strain rate. Sufficiently low strain rates were employed to ensure essentially fully drained condition. The followings were found. Despite that the newly developed pneumatic loading system is rather simple, 1D compression tests following such various loading histories as above can be performed on four types of clay rather accurately. The stress-strain behaviour of clay is significantly rate-dependent, exhibiting significant creep strains at SL stages. The creep strain rate is significantly different whether SL starts during otherwise primary loading or unloading or reloading, controlled by the magnitude and sign of the initial strain rate at the start of SL. The whole observed trends of rate-dependent stress-strain behaviour can be qualitatively explained by the non-linear three-component elasto-viscoplastic model extended to cyclic loading conditions. 相似文献
78.
Antibacterial activity of extracts from some edible plants commonly consumed in Asia 总被引:10,自引:0,他引:10
Extracts of edible plants (26 species) from China, Japan, Thailand and Yemen were screened for their antibacterial activity against Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella infantis. Buffered methanol (80% methanol and 20% PBS) and acetone extracted inhibitory substances against tested bacteria from 16 plants, as revealed by the disc assay. The minimum inhibitory concentrations (MICs) of extracts determined by the agar dilution method ranged from 165 to 2640 mg l−1. The most sensitive microorganism to extracts from Azadirachta indica, Cinnamomum cassia, Rumex nervosus, Ruta graveolens, Thymus serpyllum and Zingiber officinale was B. cereus, with MIC of 165 to 660 mg l−1. E. coli and S. infantis were only inhibited by Cinnamomum cassia extracts at the highest MIC (2640 mg l−1). L. monocytogenes (Tottori) was more resistant than the ATCC 7644 strain to extracts from Ruta chalepensis, Artemisia absinthium and Cissus spp. EDTA (0.85 mM) reduced the MICs of Cinnamomum cassia and Cissus rotundifolia by at least 50% when tested against E. coli, S. infantis, S. aureus and L. monocytogenes. 相似文献
79.
S Matsubara S Akashi K Naitoh Y Nakahara S Hayashi 《Canadian Metallurgical Quarterly》1998,36(10):886-890
A 42-year-old man was admitted because of fever, productive cough, and progressive dyspnea. Chest x-ray films and computed tomographic scans disclosed dense consolidation in the left and right lung fields. No pathogenic agent was found despite extensive bacteriological examinations. Based on serological findings, the patient was given a diagnosis of acute pneumonia caused by Legionella micdadei. It has been reported that Legionnaire's disease is easily complicated by fatal systemic illnesses such as disseminated intravascular coagulation (DIC) and multiple organ failure. In fact, the patient suffered from severe hypotension and DIC on admission. Treatments against systemic complications were started together with intravenous administration of antibiotics including erythromycin. Continuous intravenous cathecolamin, however, failed to alleviate the patient's shock. We therefore applied endotoxin eliminating therapy using a polymyxin-B-column (PMX) and continuous hemofiltration (CHF). The patient recovered from critical shock immediately after the start of PMX, which together with CHF, alleviated his systemic complications. Although the factors responsible for fatal systemic complications in Legionnare's disease are not well-documented, our findings suggested that some substances removable by PMX and CHF play an important role in pathogenesis. 相似文献
80.