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排序方式: 共有1252条查询结果,搜索用时 15 毫秒
1.
Tatsuya Hanaoka Hisashi Ishitani Ryuji Matsuhashi Yoshikuni Yoshida 《Applied Energy》2002,72(3-4):705-721
The objective of this study is to evaluate the potential for recovering fluorocarbons as measures for the abatement of global warming. In this study, we focused on the three different kinds of fluorocarbons: CFCs, HCFCs and HFCs, and targeted refrigerant use because of the availability of relevant data. We first estimated future fluorocarbon emissions from the targeted appliances; we next compared those emissions in the units of CO2 equivalent to the level of CO2 emissions in 1990 from a quantitative point of view. As the result of this study, it was found that fluorocarbon emissions in 1999 and 2010 would be equal to approximately 7 and 3% of the level of CO2 emissions in 1990 respectively. Moreover, if we implement a 100% recovery rate in every recovery route, we can reduce a large amount of emissions which correspond to approximately 2–5% of the level of CO2 emissions in 1990, even if we take into account the energy-related CO2 emissions by the transportation and decomposition of fluorocarbons. 相似文献
2.
T Noda M Arakawa T Takaya T Nagano K Kagawa H Miwa S Hirakawa 《Canadian Metallurgical Quarterly》1993,14(7):876-884
To evaluate right atrial (RA) contractile performance in patients with myocardial infarction, we validated a cineangiographic method of RA volume measurement, and investigated RA volume change in 'normal' individuals and patients with a previous myocardial infarction. Sixteen silicone rubber RA casts made from human cadavers were filmed in the postero-anterior and left lateral projections. The cast volumes calculated following Simpson's rule were in good agreement with those measured by water replacement (r = 0.992, P < 0.01). At cardiac catheterization, biplane RA cineangiography was performed in 19 'normal' individuals (N group), in 14 patients with a previous antero-septal infarction (AMI group) and in seven patients with a previous inferior infarction (IMI group). The RA volume-time curve was constructed at 20-40 ms intervals for one cardiac cycle. RA volume at the beginning of the atrial contraction (RAVd), which was defined as the 'preload' of the RA, tended to be larger in both the AMI and IMI groups compared with 'normal' individuals. The RA ejection volume was significantly larger in both the AMI (18.4 +/- 2.1 ml.m-2, P < 0.01) and IMI groups (19.4 +/- 2.8, P < 0.01) than in the N group (14.5 +/- 1.9), even for a comparable level of RAVd (range from 26 to 36 ml.m-2) (18.6 +/- 2.1, P < 0.01, 18.2 +/- 2.0, P < 0.01, 14.7 +/- 1.9, respectively). These results suggest that RA contraction increases in patients with myocardial infarction by increasing both the 'preload' and 'contractility' of the RA. 相似文献
3.
Yuji Oie Tatsuya Suda Masayuki Murata Hideo Miyahara 《International Journal of Satellite Communications and Networking》1991,9(5):285-303
One of the most promising approaches for high speed networks for integrated service applications is fast packet switching, or ATM (asynchronous transfer mode). ATM can be characterized by very high speed transmission links and simple, hard-wired protocols within a network. To match the transmission speed of the network links, and to minimize the overhead due to the processing of network protocols, the switching of cells is done in hardware switching fabrics in ATM networks. A number of designs have been proposed for implementing ATM switches. Although many differences exist among the proposals, the vast majority of them are based on self-routeing multistage interconnection networks. This is because of the desirable features of multi-stage interconnection networks such as self-routeing capability and suitability for VLSI implementation. Existing ATM switch architectures can be classified into two major classes: blocking switches, where blockings of cells may occur within a switch when more than one cell contends for the same internal link, and non-blocking switches, where no internal blocking occurs. A large number of techniques have also been proposed to improve the performance of blocking and non-blocking switches. In this paper, we present an extensive survey of the existing proposals for ATM switch architectures, focusing on their performance issues. 相似文献
4.
J Nishigami T Ohshima T Takayasu T Kondo Z Lin T Nagano 《Canadian Metallurgical Quarterly》1993,47(5):372-379
Using the TOXI-LAB drug detection system, emergency toxicological screening was performed in autopsy cases and emergency cares. In 280 autopsy cases (male 182 cases 65%, female 98 cases 35%), drug positive cases were 28 cases of male (15%) and 24 cases of female (24%). The age groups which showed higher rate of drug positive cases were 10s-40s in male (approximately 20%) and 20s in female (67%). In the 238 cases of emergency care (male 129 cases 54%, female 104 cases 44%, unknown 5 cases 2%), drugs were positive in 29 cases of male (22%) and 32 cases of female (30%). The age groups which showed relatively higher rate of drug positive cases were 40s in male (64%), 20s (71%) and 30s (89%) in female. Forty-four different kinds of drugs were detected in TOXI-LAB positive cases, in which the psychotropic drugs and the sedative-hypnotic drugs amounted to approximately 70%. Methamphetamine and amphetamine, which were the main abused drugs showing a socially important problem, were detected in total 15 cases. TOXI-LAB was based on thin-layer chromatography (TLC); however, from the extraction to development, coloration and detection have been accelerated (about 50 min) and simplified. In order to perform the forensic toxicological practice in Japan, it becomes more useful that TOXI-LAB is used in autopsy cases and emergency cares, if the drugs, which have caused poisoning cares in Japan, are added to TOXI-LAB. The present study describes the advantage and problem of TOXI-LAB drug detection system through demonstrating the practical cases of autopsy cases and emergency cares. 相似文献
5.
N Nakanishi C Nishioka A Yamada K Kimoto S Uzura Y Aoki H Yoneda K Nagano K Tatara 《Canadian Metallurgical Quarterly》1997,44(11):845-856
To estimate the risk factors for intellectual dysfunction and examine its prognosis in a community-residing (non-institutionalized) elderly population, a randomly selected sample of 1,473 elderly people aged 65 years and over living in S city, Osaka Prefecture, was studied in October 1992, and data were obtained from 1,383, a response rate of 93.9%. A cohort of 1,383 was followed for 42 months and follow-up was completed for 1,300 (94.0%). The main results were as follows: 1) The prevalence of intellectual dysfunction did not differ significantly between sexes, and there was an increasing prevalence of intellectual dysfunction with age in both sexes. The prevalence of severe intellectual dysfunction was found to increase highly at age 85 and over. 2) By univariate analysis, odds ratios for age older than 75 years, low Activities of Daily Living (ADL), urinary and fecal incontinence, and no participation in social activities were significantly higher than 1 in any level of mild, moderate, and severe intellectual dysfunction. In the multivariate analysis using logistic regression, age older than 75 years and urinary and fecal incontinence showed significant higher odds ratios than 1 for severe intellectual dysfunction, and low ADL and treatment for hypertension also showed significant higher odds ratios than 1 for moderate intellectual dysfunction. 3) From analysis using the Kaplan-Meier method, the cumulative survival rates decreased with a decline in intellectual functioning in both age groups of 65-74 and 75 years and older. 4) Application of the Cox proportional hazards model resulted in adjusted hazard ratio for severe intellectual dysfunction of 1.79 (95% confidence interval, 1.02-3.12), controlling for other factors such as sex, age, general health status, incontinence and social activities. 相似文献
6.
Color‐vision deficiency is a relatively common genetic condition, which often leads to the obstruction of necessary information in colored images. It is important to minimize such inconvenient effects in communication using colored images from a universal design perspective. The universal design principle stipulates that all environments and products should be usable by all people, regardless of age, physical attributes, and ability. This article proposes a method to detect color combinations in a given image that would confuse color dichromats, and suggests a way in which to modify them to make the image easily distinguishable for both normal and dichromatic observers. Confusing color combinations were detected based on a color‐difference calculation using simulations of how the color would appear to dichromats. The confusing colors were then modified based on the minimization of an evaluation function, which was defined as the sum of the degree of confusion and the degree of color change from the original image. Several colored images obtained by the proposed method were compared with the originals by red–green dichromatic observers who judged them to be clearer, thereby confirming that the proposed method was effective for color rendering for universal design. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 203–211, 2008 相似文献
7.
STATEMENT OF PROBLEM: Improved dental stone has been widely used for producing dies for the fabrication of restorations with the lost-wax technique. Improved dental stone is used for several reasons, but it is selected most often because of its reasonable cost, ease of use, and ability to produce consistent results. PURPOSE: This study evaluated the ability of an epoxy resin die material and a type IV dental stone to dimensionally reproduce a custom-fabricated metal die. MATERIAL AND METHODS: Dies were fabricated and measurements were made from three reference lines. Measurements were repeated three times for the master die and for the specimen dies. A mean measurement and percent relative change for each dimension was calculated. RESULTS: A significant difference in the relative change for die height was found between the groups studied (p < 0.003). CONCLUSIONS: This epoxy die system will provide a degree of dimensional accuracy comparable to gypsum when used with addition silicone impression material. 相似文献
8.
Harumi Yokokawa Tatsuya Kawada Masayuki Dokiya 《Journal of the American Ceramic Society》1989,72(1):152-153
It has been found that the enthalpy of formation of perovskite compounds, Δf H° (ABO3 , B = transition metais), from binary oxides can be well characterized in terms the tolerance factor, t≡(rA + ro )√2 (rB + ro ), where rA and rB are the radii of A-site ions with 12-coordination and B-site ions with 6-coordination, respectively, and Δf H°=−168 + 270(1 − t) kJ·mol−1 for AI BV O3 , Δf H°=−125 + 1000(1 − t) kJ·mol−1 for AII BIV O3 , and Δf H°=− 90 + 720(1 − t) kJ·mol−1 for AIII BIII O3 . Although the thermodynamic data of K2 NiF4 compounds are not extensive, a similar regularity can be found when use is made of the radii of A-site ions with 9-coordination for the K2 NiF4 compounds. These correlations will be quite useful in predicting. 相似文献
9.
High oleic acid oil suppresses lung tumorigenesis in mice through the modulation of extracellular signal-regulated kinase cascade 总被引:2,自引:0,他引:2
Yamaki T Yano T Satoh H Endo T Matsuyama C Kumagai H Miyahara M Sakurai H Pokorny J Shin SJ Hagiwara K 《Lipids》2002,37(8):783-788
This study was undertaken to estimate the effect of dietary high oleic acid oil (OA) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone
(NNK)-induced lung tumorigenesis in mice. Diet containing 10% oil was fed to mice through experimental periods. On day 30
after NNK injection (100 mg/kg body weight, i.p.), the treatment increased the level of prostaglandin E2 (PGE2) as well as proliferating cell nuclear antigen, a marker of cell proliferation in a high linoleic acid oil (LA)-fed group
but not in an OA-fed group. The NNK treatment also induced the activation of an extracellular signal-regulated kinase (Erk)
cascade (Erk, Mek and Raf-1) in an LA-fed group. On the other hand, OA feeding abolished the NNK-induced activation of the
Erk cascade. In conjugation with these events, OA feeding reduced lung tumor incidence and tumor multiplicity (percentage
of mice with tumors) in mice compared with LA feeding at the 20th experimental week. These results suggest that OA suppresses
lung tumorigenesis and that this suppression is correlated with the inhibition of PGE2 production and inactivation of the Erk cascade. 相似文献
10.
Masaru Takahashi Noriyuki Inoue Tatsuya Takeguchi Shinji Iwamoto Masashi Inoue Tsunenori Watanabe 《Journal of the American Ceramic Society》2006,89(7):2158-2166
The reaction of mixtures of aluminum isopropoxide and gallium acetylacetonate in 1,4-butanediol or 1,5-pentanediol at high temperatures (glycothermal reaction) directly gave the γ-Ga2 O3 –Al2 O3 solid solutions, which had high catalytic activities for selective reduction of NO using methane as the reducing agent. However, the reaction with a higher Al/(Ga+Al) charged ratio yielded the glycol derivative of boehmite as a by-product and the catalytic activity of the solid solution decreased. Therefore, synthesis of the solid solution using various glycols was examined and it was found that solid solutions with high Al contents without contamination of the glycol derivative of boehmite were obtained by using 1,6-hexanediol as a reaction medium. The solid solution exhibited a higher NO conversion than that synthesized in other glycols. 相似文献