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31.
Y. Uzawa M. Takeda A. Kawakami Z. Wang 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(10):1749-1757
A novel broadband tuning circuit composed of two low-current-density half-wave NbN/MgO/NbN tunnel junctions connected by a half-wave NbN/MgO/NbN microstrip line has been successfully tested in a quasi-optical mixer at frequencies above 700 GHz. The circuit had a designed center frequency of 870 GHz, was integrated in a center-fed twin-slot antenna, and was fed via a quarter-wave impedance transformer. Heterodyne measurments showed double-side-band receiver noise temperatures equivalent to 6-9 quanta from 675 to 810 GHz for a mixer with a current density of 6.7 kA/cm2. The RF bandwidth was broader than that of a conventional mixer using a full-wave junction with the same current density. 相似文献
32.
Yoshinobu Lshii Takanori Nagasaki Naoki Igawa Hitoshi Watanabe Hideo Ohno 《Journal of the American Ceramic Society》1991,74(9):2324-2326
Temperature dependence of the Raman spectrum of lithium oxide single crystal has been measured over a temperature range of 80 to 1073 K. The frequency shift and the line width of the Raman spectrum in lithium oxide were about 531 and 4.5 cm-1 at 80 K, respectively. At 1073 K, the frequency shift and the line width attained the values of 464 and 112 cm-1 , respectively. The strong temperature dependence of the frequency shift and line width was compared with data from some crystals with a fluorite structure. 相似文献
33.
I Araki H Zakoji M Komuro Y Furuya M Fukasawa Y Takihana M Takeda 《Canadian Metallurgical Quarterly》2003,170(5):1901-1904
34.
Remi Kasai Hideaki Yaegashi Hiroshi Yokoyama Masahiko Yamanaka Hideo Sawada 《Journal of Materials Science》2007,42(24):10228-10238
Fluoroalkanoyl peroxides reacted with FULLERENES [fullerene (C60) and commercially available fullerenes (Nanom MixTR and Nanom BlackTR)] and radical polymerizable comonomers such as acrylic acid, N,N-dimethylacrylamide, N-(1,1-dimethyl-3-oxobutyl)acrylamide, and acryloylmorpholine to afford fluoroalkyl end-capped cooligomers having FULLERENES
in the main chain under very mild conditions. Fluoroalkyl end-capped Nanom Mix and Nanom Black cooligomers thus obtained were
found to exhibit a similar solubility to that of the corresponding fluoroalkyl end-capped cooligomers having fullerene in
the main chain. These fluorinated FULLERENES cooligomers were found to form the nanometer size-controlled self-assembled cooligomeric
aggregates in aqueous solutions. These fluoroalkyl end-capped FULLERENES cooligomers were more effective for solubilizing
fullerene, Nanom Mix and Nanom Black into water, compared to those of the corresponding fluoroalkyl end-capped homooligomers
having no FULLERENES in the main chain. Fluoroalkyl end-capped fullerene- and Nanom Mix-acrylic acid cooligomers were found
to exhibit fluorescence spectra related to fullerene and Nanom Mix in cooligomers, respectively, in aqueous solutions. Additionally,
these fluorinated fullerene- and Nanom Mix-acrylic acid cooligomers were able to increase chemiluminescence intensity related
to luminol, effectively, compared to the corresponding fluorinated acrylic
acid homooligomers. 相似文献
35.
To unlock the full potential of evolution in digital media, a Tierra-like system using network-type assembly-like language
has been constructed. In the system, like Avida, digital creatures, self-replicating programs, live in a discrete 2D torus
space and an interaction between creatures is restricted locally. Bearing a genetic network in mind, network structure is
introduced. In the previous works, it is shown that the possibility that the network-type model has more potential of evolution
than a linear-type model like Avida in a simple environment. In this paper, to study the potential of evolution more precisely,
we model the effects of environment other than creatures. As one of the simplest models of such environment, the cost of execution,
i.e. executing time, is introduced. The difficult environment to live in costs high to execute instructions, the easy environment
does low. In computer experiments, we have investigated the influence of change in environment by analyzing the process of
evolution and diversity of the system. Experimental results show that the network-type system keeps more stable diversity
than the linear-type system does, even when the environment changes drastically. This indicates the possibility that the network-type
system has more potential of evolution than the linear-type system has.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
36.
To present axes for evaluating the water resources, lake environment and water use in a lake and its watershed, a comparative study was done for four East Asian lakes; lake Kasumigaura (Japan), Lake Laguna (Philippines), Lake Songkhla (Thailand) and Lake Dianchi (China). Two axes were then determined from the relationship between: (1) water use and water supply rate, and (2) water use and water quality. To clarify the meanings ‘carrying capacity’ and ‘vulnerability’, the maximum population density in the lake basin and total nitrogen concentration in the lake water were calculated and discussed to decide the direction of environmentally sound management of the drainage basin. 相似文献
37.
A 32-year-old male was diagnosed as having miliary tuberculosis in May 1990. In spite of antituberculosis chemotherapy, he developed tuberculous meningitis and intracranial tuberculoma in September 1990. Miliary shadows on chest X-ray disappeared in December 1990. However, he developed left atelectasis, and bronchofiberscopy revealed soft tumor in the left main bronchus in January 1991. He suddenly vomited large amounts of blood and expired in February 1991. At autopsy, tuberculous lymphadenitis and cavitation were noted in the mediastinum, through which the left main bronchus, esophagus and descending aorta communicated. The patient died of massive bleeding which resulted from the rupture of tuberculous aortitis into the esophagus. This is a very rare case of tuberculous aortic aneurysm rupturing into both the bronchus and esophagus. 相似文献
38.
T Shirasaka K Nakano T Takechi H Satake J Uchida A Fujioka H Saito H Okabe K Oyama S Takeda N Unemi M Fukushima 《Canadian Metallurgical Quarterly》1996,56(11):2602-2606
The purpose of this study was to establish a nude rat orthotopic (organ-specific) human colorectal cancer model as an in vivo secondary screen for general evaluation of new anticancer agents against colorectal cancer and to evaluate practically the antitumor activity of 1 M tegafur-0.4 M 5-chloro-2,4-dihydroxypyridine-1 M potassium oxonate (S-1), a new p.o. fluoropyrimidine, in comparison to 1 M tegafur-4 M uracil [(UFT) effective on colorectal tumor in clinical]. After implantation of KM12C, a human colorectal cancer cell line, into the subserosal layer of the colon as a single-cell suspension, extensive local tumor growth and invasion to both the mucosal and the serosal sides were observed in all rats. Metastatic foci were also formed in both lymph nodes and lungs following local tumor growth in all of them. Using this method, an equitoxic dose of S-1 (15 mg/kg/day) and UFT (30 mg/kg/day) was administered p.o. for 14 consecutive days from 7 days after tumor cell implantation. S-1 showed a higher tumor growth inhibition than UFT did [S-1, 57% (significantly different from the tumor weight of the untreated group at P < 0.05) and UFT, 18% (P > 0.05)]. When both drugs were administered to nude rats bearing KM12C injected into the cecal wall for 28 consecutive days at equitoxic doses, the mean survival in the S-1 group was 16 days longer than that in the untreated group (P < 0.01) but that in the UFT group was only 8 days longer (P > 0.05). After the administration of an equitoxic dose of both drugs, S-1 gave the higher levels than UFT in various pharmacokinetic parameters as follows: area under the curve 0-24 h of 5-fluorouracil in plasma (3.5-fold), area under the curve 0-24 h of 5-fluorouracil incorporated into RNA in the tumor (1.3-fold), and thymidylate synthase inhibition rate (percentage) in the tumor (about 20%). Collectively, these findings suggested that this orthotopic human colorectal tumor model in nude rats is useful to evaluate the clinical therapeutic efficacy of drugs or therapies for colorectal cancer, and that S-1 had a higher therapeutic effect on human colorectal tumor than UFT did. 相似文献
39.
Air-pollutant transport within an urban setting is conditioned by local urban geometry, urban-modified meteorological variables, a wide variety of source characteristics and local topography. Extreme complexity and local specificity of the resulting dispersion process requires the use of physical modeling rather than numerical or analytical methods to predict concentration distributions. Serving as an analog computer the boundary-layer wind tunnel provides reliable concentration data which can be applied directly to design and/or decision making.A brief review is made of similarity criteria for simulating physical modeling of the atmospheric boundary-layer and source characteristics in a boundary-layer wind tunnel. Applications to several problems related to stack, vent and automobile emissions are described. Rudimentary portions of a data bank are presented which, with additional data acquisition, can provide a practical method for prediction of automobile exhaust concentrations that will result from proposed freeways or alternative traffic routings. 相似文献
40.
Okamura H. Atsumo T. Takeda K. Takada M. Imai K. Kinoshita Y. Yamazaki T. 《Solid-State Circuits, IEEE Journal of》1996,31(1):84-90
A BiCMOS logic circuit with very small input capacitance has been developed, which operates at low supply voltages. A High-beta BiCMOS (Hβ-BiCMOS) gate circuit which fully utilizes the bipolar transistor features achieves 10 times the speed of a CMOS gate circuit with the same input capacitance and operating at 3.3 V supply voltage. In order to lower the minimum supply voltage of Hβ-BiCMOS, a BiCMOS circuit configuration using a charge pump to pull up the output high level of the BiCMOS gate circuit is proposed. By introducing a BiCMOS charge pump, Hβ-BiCMOS achieves very high speed operation at sub-2.0 V supply voltage. It has also been demonstrated that only a very small number of charge pump circuits are required to drive a large number of Hβ-BiCMOS gate circuits 相似文献