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排序方式: 共有553条查询结果,搜索用时 31 毫秒
1.
为了使橡胶混炼设备能够适应新材料新工艺的快速发展,在现今不稳定的商业投资环境下,选择一种高度灵活性的传动系统,既能使设备保有先进性,又能很快得到投资回报,可谓为一种不可多得的投资理念,Haqqlunds公司生产的带液压电机传动系统,可使相切型密炼机的产品质量远远好于采用传统的固定速度,速比密炼机的产品质量,也可使啮合型密炼机充分利用所配置的传动功率,还可广泛用于开炼机,双螺杆压片机和压延机,业已证明,其工作可靠,维修便宜。 相似文献
2.
K. Fujii J. Fujimoto H. Hayashii R. Kajikawa Y. Masatani H. Ozaki A. Sugiyama R. Suzaki S. Suzuki T.Y. Tsukamoto T.F. Tsukamoto S. Uno S. Iwata 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,236(1):55-63
We constructed and tested a prototype gas sampling electromagnetic calorimeter of the Pb-proportional tube sandwich type. The calorimeter uses conductive plastic tubes and cathode pad readout with a tower structure which resulted in reasonable energy and spatial resolutions for electrons in the momentum range 0.5–4.0 GeV/c; /c). This paper describes the test and the performance studied under various conditions. 相似文献
3.
An advanced learning system for interactive simulation of patient cases (ISP) is described. The system was designed to meet specific pedagogical needs where student activation and problem orientation were two of the key issues. The system includes features such as video based illness history-taking function using free text input, highly interactive physiological examination procedures, extensive laboratory tests and detailed user feedback. The system was constructed mainly in Authorware Professional, starting more than 10 years ago, and it is now available in refined versions in different languages. Twelve pedagogical and three technical features were initially defined for the project. All of these aims were fulfilled. The ISP system has been successfully used in education, and in international collaboration, including three applicability field tests. The system is also a powerful research tool for studying for instance medical decision-making. 相似文献
4.
SL Kamholz RJ Brewer G Grijalva J Burack MJ Del Rio M Vaynblatt N Lawson S Squinto WL Fodor AJ Norin 《Canadian Metallurgical Quarterly》1997,21(9):951-955
The lack of sufficient suitable human donor lungs for the many patients requiring pulmonary transplantation as life-saving therapy for end-stage lung diseases has generated extensive interest in cross-species lung transplantation. Ethical concerns and those of animal rights advocates have prompted studies of nonprimate species as potential solid organ donors for humans. This paper provides an overview of some of the laboratory studies of cross-species pulmonary transplantation performed over the past 20 years and focuses, in particular, on more recent work (from our laboratory and others) in the area of porcine-to-primate pulmonary xenotransplantation. 相似文献
5.
Yoshiyuki Uno Akira Okada Kensuke Uemura Purwadi Raharjo Toshihiko Furukawa Kosaku Karato 《Precision Engineering》2005,29(4):171-455
A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds. 相似文献
6.
Susana Criado Norman A. García Maria I. Gutirrez Vicente Avila Sonia G. Bertolotti Rio Cuarto 《European Journal of Lipid Science and Technology》1996,98(5):172-175
The ability of mono-, di-, tri-and tetra-hydroxyflavones (7-and 3-hy-droxyflavones, 7, 8-dihydroxyflavone, baicalein and fisetin) to act as photoprotectors against singlet molecular oxygen [O2(Δg)]-initiated photooxidation of fats has been established by a kinetic study. The overall quenching rate constants for a series of five hydroxyflavones perfectly parallel their respective behaviour as inhibitors of the sensitized photooxidation of linoleic acid. The best antioxidative effect was exerted by 7-hydroxyflavone which does not chemically react with O2(1Δg). Nevertheless for the remaining flavonoids of the series, the physical deactivation of O2(1Δg) largely prevails over the chemical process. As for the cases of phenols and related hydroxy-aromatic derivatives, the ionization of the -OH group in the flavones, dramatically accelerates the rate of photooxidation. Under these conditions, the 7-hydroxyflavone also reacts effectively with O2(1Δg). Given that flavonoids are natural oil components, this medium effect should be taken into account during the oil-refining process, in order to avoid the flavonoid photodestruction. 相似文献
7.
An HIP compact of MA-processed powder having a nominal composition of Ti-48at.% Al was produced. The compact consisted of a large amount of TiAl(λ) and a small amount of Ti3Al (2), in a completely ultra-fine equiaxed grain structure. This two-phase compact showed typical superplastic deformation behaviour. A maximum elongation of 550% was obtained. A strain exponent, n = 2, and grain size exponent, p = 2, were determined from the results of a strain-rate-change test and a creep test at constant initial stress using samples having various grain sizes, respectively. The activation energy for creep, Qc at constant stress was calculated to be 350 kJ/mole. It is concluded that the superplastic deformation mechanism of the material under study is grain boundary sliding controlled by lattice diffusion in the TiAl phase. 相似文献
8.
XIII. Yeast sequencing reports. Cloning and sequencing of the NES24 gene of Saccharomyces cerevisiae
We have cloned NES24 using a temperature-sensitive nes24-1 mutant as a host and sequenced a 3162 bp XhoI-EcoRI DNA fragment containing the NES24 gene. Computer analysis revealed that this segment contains a 1806 bp open reading frame which is needed for complementation of the nes24-1 mutation. We found SUP8 in the region upstream of the NES24 gene, placing the NES24 gene on chromosome XIII. A protein homology search indicated that NES24 encodes a new protein. The disruption of the NES24 gene resulted in temperature-sensitive growth. The sequence has been deposited in DDBJ/EmBL/GenBank data bases under Accession Number D15052. 相似文献
9.
Imageability of places, cities and countries is strongly influenced by tourist and political portraits in the media. As human cognition relies on inferential perception and contrasting categories, marketing strategies exploit partial truths and conflicting city images to direct public perceptions. This article addresses the relationship between international perception, image building and urban design in the case of Brazil and the cities of Rio de Janeiro and Curitiba. Their contrasting images as exploited by the international media expose only partial truths. In fact, these images represent complementary development contradictions that co-exist in any major city today. 相似文献
10.
Genetic analysis of the role of cAMP in yeast 总被引:47,自引:0,他引:47