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101.
This report describes a method of determining irradiation effectiveness of different neutron spectra in causing radiation effects to fuel cladding and reactor structural materials. It involves the definition of a semi-empirical damage function or cross section using measured data from specimens irradiated in thermal and fast test reactor spectra. The damage function is applied to design problems involving irradiation effects to reactor structural and fuel cladding materials to predict the fluence which would produce a specific change in material properties. 相似文献
102.
103.
Supachai Ngamsinlapasathian Sorapong Pavasupree Yoshikazu Suzuki Susumu Yoshikawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3187-3192
Nanocrystalline mesoporous titania was obtained by surfactant-assisted templating method using tetraisopropyl orthotitanate modified with acethylacetone and laurylamine hydrochloride as template. This material was applied for the electrode of dye-sensitized solar cell. The mesoporous TiO2 (MP-TiO2) cells exhibited higher short-circuit photocurrent density and solar energy conversion efficiency compared to P25 (a typical commercial titania powder) cells. The incident photon to current conversion efficiency spectrum of MP-TiO2 can be improved by using the cell made with 5% P25 additive. Double-layer titania cells were fabricated to further improve cell performance by increasing the film thickness and light scattering. The solar conversion efficiency up to 8.06% was obtained by using the double-layer titania cell sintered at 450 °C for 2 h. 相似文献
104.
Tomita N. Ohtsuka N. Miyamoto J. Imamiya K. Iyama Y. Mori S. Ohsima Y. Arai N. Kaneko Y. Sakagami E. Yoshikawa K. Tanaka S. 《Solid-State Circuits, IEEE Journal of》1991,26(11):1593-1599
To meet the increasing demand for higher-density and faster EPROMs, a 16-Mb CMOS EPROM has been developed based on 0.6-μm N-well CMOS technology. In scaled EPROMs, it is important to guarantee device reliability under high-voltage operation during programming. By employing internal programming-voltage reduction and new stress relaxation circuits, it is possible to keep an external programming voltage V pp of 12.5 V. The device achieves a 62-ns access time with a 12-mA operating current. A sense-line equalization and data-out latching scheme, made possible by address transition detection (ATD), and a bit-line bias circuit with two types of depletion load led to the fast access time with high noise immunity. This 16-Mb EPROM has pin compatibility with a standard 16-Mb mask-programmable ROM (MROM) and is operative in either word-wide or byte-wide READ mode. Cell size and chip size are 2.2 μm×1.75 μm and 7.18 mm×17.39 mm, respectively 相似文献
105.
To succeed in the graphics controllers market, it is important to take advantage of embedded DRAMs, which provide low power consumption, low electromagnetic interference (EMI), smaller board space, and frame memory flexibility (capacity, access speed, and bandwidth). These capabilities benefit portable PC applications in which board space and power consumption are serious considerations. The MSM7680 accelerator is ideally suited for a compact multimedia system because of its smaller, embedded DRAM capacity. The MSM7680 provides high performance and/or a one-chip solution for many graphics display systems. It also integrates the frame buffer with graphics controller functions such as a 2D drawing engine, MPEG-1 decoder, digital/analog converter for RGB analog output, and a clock generator phase-locked loop. The MSM7680 multimedia accelerator uses a 256-bit data bus with embedded 1.25-Mbyte DRAM to increase the rate of data transfers and decrease power consumption 相似文献
106.
107.
K Hosokawa S Yoshitatsu M Kakibuchi S Nishimoto M Higashiyama K Yoshikawa 《Canadian Metallurgical Quarterly》1998,102(2):448-449
We report a case of identical twins with recessive dystrophic epidermolysis bullosa, who developed squamous cell carcinoma in the hand at the latter half of their third decade. To our knowledge, this is the first case of manifestation of squamous cell carcinoma in identical twins and may contribute to the understanding of oncogenesis in such patients. 相似文献
108.
M Sunaga M Yoshikawa M Ebara F Kondo M Kashiwada T Takemori H Saisho 《Canadian Metallurgical Quarterly》1998,13(9):878-884
OBJECTIVE: Studying gender differences in fat mass and distribution in a homogeneous group of children. DESIGN: Cross-sectional study. SUBJECTS: 610 children aged 5-7 y in Kiel, Germany. METHODS: Anthropometric measures, bioelectrical impedance analysis (BIA). RESULTS: Although boys had increased body weights (P<0.05), body mass indexes (BMI's) (P<0.001) and waist/hip ratios (WHRs) (P<0.001), the %fat mass as assessed by BIA (P<0.05) was increased in girls. Although the increased BMI in boys was independent of the percentile used, gender differences (that is, lower values for boys than for girls at the same age) in WHR, the sum of four skinfolds and %fat were seen up to the 90th percentile. By contrast, above the 90th percentile there were no differences in skinfold thickness and %fat between boys and girls. Studying 42 BMI-matched pairs (boys and girls) also showed that the %fat estimated by BIA (P<0.001) was increased in girls. Plotting the average of %fat as obtained from skinfold- and BAI-measurements against the difference between data obtained by the use of the two methods shows that BIA %fat overestimates skinfold %fat at low or normal percent fat mass (that is, up to 20%) in both genders. By contrast, at increased fat mass, BIA %fat seems to underestimate skinfold %fat in both genders. CONCLUSIONS: Gender differences in fat mass and fat distribution are obvious in children aged 5-7 y. These differences are independent of gender differences in body weight. However, the nutritional state has an influence and gender differences cannot be detected in overweight and obese children. Our data also suggest that a children-specific formula used to calculate %fat from skinfold measurements is inappropriate. 相似文献
109.
110.
For the hydrogenation of Japanese Taiheiyo coal, a new catalyst, Saechol, formed on the surfaces of blades made from molybdenum-containing alloys such as SUS316, SCM3 and SKH9 showed significant activity. The activity survived in the flame but was lost easily by washing in 6N hydrochloric acid. The activity was easily regenerated. Several procedures for generation of activity are reported. 相似文献