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61.
An experimental study has been made of the chaotic behavior in the transition to turbulence of flow through porous media consisting of a bank of tubes in a narrow gap. Judging from the examination of the correlation dimension and the maximum Lyapunov exponents, we can identify the chaotic behavior in porous media for Re > ~60. Rapid increase in the maximum Lyapunov exponents was observed for Re > ~300. Also, the spatial distribution of the Lyapunov exponents is discussed.  相似文献   
62.
This paper describes a simulation model for a spray flash desalination system which makes fresh water from sea water by using the temperature difference between warm surface sea water and cool deep sea water. The spray flash desalination system can be modeled by using the energy conservation law and the mass conservation law. Simulation results of the model are compared with the experimental results and show the accuracy of the proposed simulation model. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(4): 9–17, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20975  相似文献   
63.
As heat generation in satellites increases, ensuring that they are provided with sufficient radiator panel area is an important problem. Deployable radiators, with radiator panels that are deployed post‐launch in space to increase the satellite's effective radiator panel area of the satellite, are becoming an important thermal control technology. A reservoir embedded loop heat pipe (RELHP) is used in deployable radiators as a heat transport device. A deployable radiator of this type was mounted on the ETS‐VIII satellite, which was launched on December 18, 2006 and injected into a geostationary orbit. The satellite is still operating without any significant issues over two years later. This paper investigates the heat transport characteristics of an RELHP system used in a deployable radiator in a geostationary orbital environment. This system can be successfully started up in a micro gravity environment. We also found that the sub‐cooling region is shorter in a micro gravity environment than in a terrestrial gravity environment, because there is less heat leakage into the reservoir in a micro gravity environment. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20346  相似文献   
64.
Three peptides (5A, 5C and 6C), purified from potato protein hydrolysate fractions, possessed antioxidative activities. Isolation and purification were carried out using gel permeation chromatography and successive reverse-phase HPLC. These three peptide fractions were sequenced and identified as Phe-Gly-Glu-Arg, Phe-Asp-Arg-Arg and Phe-Gly-Glu-Arg-Arg, respectively. The fractions 5A, 5C and 6C inhibited linoleic acid oxidation by 55.3%, 58.5% and 61.7% using β-carotene decolorization assay system, while the inhibition ratio was 32.1%, 93.0% and 93.4% in the ferric thiocyanate assay system, respectively. The peptide fractions 5A, 5C and 6C also repressed lipid oxidation by 24.2%, 14.7% and 26.4% in the erythrocyte membrane ghost assay system, respectively. Oral administration of 100 mg/kg of body weight of the chemically synthesized peptides, 5A, 5C and 6C to rats (male Wistar) 30 min prior to ethanol injection reduced ethanol-induced gastric mucosal damage by 67.9%, 57.0% and 60.3%, respectively. Conclusively, these peptides have shown real potent antioxidative activities and could further be investigated for potential use as food additives.  相似文献   
65.
In this paper we propose an object-triggered human memory augmentation system named “Ubiquitous Memories” that enables a user to directly associate his/her experience data with physical objects by using a “touching” operation. A user conceptually encloses his/her experiences gathered through sense organs into physical objects by simply touching an object. The user can also disclose and re-experience for himself/herself the experiences accumulated in an object by the same operation. We implemented a prototype system composed basically of a radio frequency identification (RFID) device. Physical objects are also attached to RFID tags. We conducted two experiments. The first experiment confirms a succession of the “encoding specificity principle,” which is well known in the research field of psychology, to the Ubiquitous Memories system. The second experiment aims at a clarification of the system’s characteristics by comparing the system with other memory externalization strategies. The results show the Ubiquitous Memories system is effective for supporting memorization and recollection of contextual events.  相似文献   
66.
Terpendole E is first natural product found to inhibit mitotic kinesin Eg5, but its inhibitory mechanism remains to be revealed. Here, we report the effects of terpendole E and 11ketopaspaline (a new natural terpendole E analogue) on the Eg5–microtubule interaction and in several Eg5 mutants. 11‐Ketopaspaline is a shunt product from terpendole E, and it shows potent inhibitory activity against the microtubule‐stimulated ATPase activity of Eg5. Unlike other Eg5 inhibitors, such as S‐trityl‐L ‐cysteine (STLC) and GSK‐1, both terpendole E and 11‐ketopaspaline only partially inhibited Eg5–microtubule interaction. Furthermore, terpendole E and 11‐ketopaspaline inhibited several Eg5 mutants that are resistant to STLC (Eg5D130A, Eg5L214A) or GSK‐1 (Eg5I299F, Eg5A356T), but with the same extent of inhibition against wild‐type Eg5. Because Eg5D130A and Eg5L214A show cross‐resistance to most known Eg5 inhibitors, which bind the L5 loop, these results suggest that terpendole E and its analogues have a different binding site and/or inhibitory mechanism to those for L5 loop‐binding type Eg5 inhibitors.  相似文献   
67.
INTRODUCTI0NUnsteadyphenomenaappearedinacentrifugalcompressorsystematlowflowratearecharacterizedbysurgeandrotatingstall.Thesurgeisknowntocauseoscillationswithlargeamplitudeofthefiowrateandthepressurerisethrough0utacompressorsys-tem.Ontheotherhand,ther0tatingstallcauseslocalflowoscillationsandappearsinsomepartsofacompressor,suchastheinducer,theimpellerandthediffuser-Sincetheydeterioratethecompressorperfor-manceands0metimesleadtothesystembreakd0wn,itisimportanttoknowthephysicalmechanismsofth…  相似文献   
68.
Engineering liver tissue constructs with sufficient cell mass for transplantation implies culturing large numbers of hepatocytes in a reduced volume; however, providing sufficient oxygen to dense cell cultures is still not feasible using only conventional culture medium. Liposome-encapsulated hemoglobin (LEH), an oxygen-carrying blood substitute originally designed for short-term perfusion, may be a good candidate as an oxygen carrier to cultured liver cells. In this study, we investigated the feasibility of maintaining long term hepatocyte cultures using LEH. Primary fetal and adult rat liver cells were directly exposed to LEH for 6 to 14 days in static culture or in a perfused flat plate bioreactor. The functions and viability of adult rat hepatocytes exposed to LEH were not adversely affected in static monolayer culture and were even improved in the bioreactor. However, some cytotoxicity of LEH was observed with fetal rat liver cells after 4 days of culture. LEH, though a suitable oxygen carrier for long-term culture of mature hepatocytes, is not suitable in its present form for perfusing fetal hepatocyte cultures in direct contact with the liposomes; either the LEH will have to be made less toxic or a more sophisticated bioreactor that prevents the direct contact between hepatocytes and perfusates will have to be designed if fetal cells are to be used for liver tissue engineering.  相似文献   
69.
Unno Y 《Applied optics》2011,50(3):271-281
Theoretical modeling of a slit-scan-type aerial image measurement sensor used for optical lithography is presented. Slit transmission properties are fully represented by the slit transfer function in terms of incident and scattering angles of light, which is then incorporated into the scheme of a partially coherent imaging formula to obtain an expression for image profiles measured by slit scanning. As an exemplary case, we analyze the influence of a 100 nm width slit used in an ArF lithography system. To understand the mechanism of image profile changes by slit transmission, we focus on frequency transfer characteristics of sinusoidal patterns.  相似文献   
70.
Room-temperature tensile property and fracture mode of B2-type polycrystalline CoTi intermetallic compound was studied as functions of microstructure and environment. Using a hot-rolled CoTi sheet, various microstructures were prepared by different heat treatments and pre-straining. Tensile elongation as well as ultimate tensile strength (UTS) of specimens deformed in vacuum (i.e. intrinsic tensile elongation and strength) depended on microstructure. The hot-rolled and recovered specimens showed higher elongation and tensile strength than the fully-annealed and aged specimens. Also, the pre-strained specimen showed the improved elongation and UTS in comparison with the fully-annealed specimen. On the other hand, tensile elongation and UTS of the specimens deformed in air were lower than those of the specimens deformed in vacuum, irrespective of microstructure. The extent of embrittlement was lower in the hot-rolled, recovered and pre-strained specimens than in the fully-annealed and aged specimens. SEM observation for the hot-rolled and recovered specimens showed that the quasi-cleavage fracture mode was dominant irrespective of testing environment. However, the fully-annealed, aged and pre-strained specimens consisting of recrystallized grains exhibited quasi-cleavage fracture mode mixed with intergranular fracture mode. The results showed that not only the intrinsic room-temperature tensile properties but also the environmental embrittlement of CoTi intermetallic compound depended upon lattice defects (such as dislocations and vacancies) in addition to grain size and morphology.  相似文献   
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