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991.
Junha Kim Jinhwan Jung Kwanghee Nam 《Industrial Electronics, IEEE Transactions on》2004,51(2):312-320
An integrated starter/alternator (ISA) is normally designed to have high pole structure (10-14 poles) for high starting torque. However, its back electromotive force (EMF) at the peak revolutions per minute should be less than its battery voltage for the power flow control. For example, the back-EMF of a 12-pole ISA should be 42 V at 6000 r/min. These types of conflicting requirements lead to a nonclassical motor design that has extremely large field-weakening range (8:1/spl sim/10:1). In this paper, we are considering the use of an induction machine instead of a permanent synchronous machine. As an idea for solving the voltage limit problem, two inverters are utilized with an objective of sharing the required voltage. The secondary inverter only takes care of the reactive voltage component that grows very fast in high-speed operation. Therefore, an extra voltage source is not required for the secondary inverter. Only a capacitor bank suffices for the secondary inverter. 相似文献
992.
The solutions of the Navier-Stokes equation for a Newtonian flow through a 4/1 contraction tube were obtained numerically
using the Galerkin finite element method with the nine-node Lagrangian element which was believed to be one of the most accurate
tools for mixed-type interpolating formulations. It was proved from this study that the vortex occurrence in the entrance
corner region were confirmed but its size was gradually decreased with the increase of Reynolds numbers, and that the velocity
profiles and pressure distributions along the applied mesh layers were in agreement with the experimental and the previously
reported numerical results. 相似文献
993.
It was reported that a nanocrystal ZnO had a thermal stabilizing effect for branched low‐density polyethylene (BLDPE). In this study, the thermal stabilizing effect of the nanocrystal ZnO was studied in more detail in comparison to a conventional, micron‐size ZnO using several polymers and a common antioxidant. The experimental results in this investigation suggest that the nanocrystal ZnO particles have different surface properties from micron‐size particles because of their extremely small size, and the particular surface properties are responsible for the thermal stabilizing effect. Polym. Eng. Sci. 44:1702–1706, 2004. © 2004 Society of Plastics Engineers. 相似文献
994.
Jung‐Bae Jun Min‐Su Seo Seong‐Heun Cho Jin‐Gyu Park Jee‐Hyun Ryu Kyung‐Do Suh 《应用聚合物科学杂志》2006,100(5):3801-3808
In the electroless plating process, to omit a sensitizing process with SnCl2, we utilized amino‐functional groups on polymer particles. At first, highly monodisperse functional polymer particles could be prepared by a two‐step seeded polymerization of styrene, divinylbenzene, and glycidyl methacrylate. Then, surface epoxy‐functional groups were converted to amino‐functional groups by treating the particles with a diamine. By using these surface amino functionalities, we tried to prepare uniformly metal‐coated monodisperse polymer particles by electroless plating method. The constituents of an electroless nickel solution bath are nickel salt, a reducing agent, suitable complexing agents, and stabilizers. And the metal thickness was simply controlled by changing the loading amount of substrate polymer particles. Morphological observation of nickel‐plated polymer particles was conducted by using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The structural composition of plated nickel was also investigated. Most of all, the function and the efficiency of the amino‐functional group of polymer particles as a polymeric ligand for metal binding was elucidated. From all observations, it was evident that in the electroless metal plating process without any sensitization step, the deposition of metal clusters on substrate particles is largely dependent upon the particle surface functionality. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3801–3808, 2006 相似文献
995.
996.
JD McPherson MC Krane CB Wagner-McPherson CH Kos HS Tenenhouse 《Canadian Metallurgical Quarterly》1997,41(5):632-634
The precise chromosomal localization of the type II renal-specific Na+-phosphate (Pi) cotransporter (NPT2) gene (gene symbol SLC17A2) is necessary for the identification of closely linked polymorphic markers to determine whether NPT2 is a candidate gene for inherited disorders of renal Pi reabsorption. Recent studies by two different groups localized NPT2 to human chromosome 5q35 and 5q13, respectively. To resolve this discrepancy, we used three independent methods. The results using a human chromosome 5/rodent somatic cell hybrid deletion panel, fluorescence in situ hybridization with a PAC clone containing the NPT2 locus, and analysis of a chromosome 5-specific radiation hybrid panel were all consistent with the 5q35 assignment of the NPT2 gene. The radiation hybrid results placed NPT2 between polymorphic microsatellite markers D5S498 and D5S469. These findings will allow the initiation of linkage analysis to determine if NPT2 has a causative role in Mendelian disorders of renal Pi wasting. 相似文献
997.
Monosialoganglioside (GM1) immunofluorescence in rat spinal roots studied with a monoclonal antibody
M Molander CH Berthold H Persson K Andersson P Fredman 《Canadian Metallurgical Quarterly》1997,26(2):101-111
The rate of reaction of monochlorobimane with glutathione (GSH) was measured in native human mammary MCF-7 adenocarcinoma cells (MCF-7wt) and sublines displaying resistance to 4-hydroperoxycyclophosphamide (MCF-7hc) and adriamycin (MCF-7adr) prior to examination by epifluorescence and confocal microscopy. After a 60-min incubation period at 37 degrees C, essentially all GSH was conjugated in the MCF-7wt and MCF-7adr cell lines whereas only 80% of the GSH was conjugated in the MCF-7hc line. All three lines displayed significant export of the conjugate from the cell during this period, with the MCF-7adr line displaying the most rapid efflux with 85% of the conjugate exported within 60 min. Epifluorescence microscopy detected an approximately 20% increase in integrated fluorescence intensity in the nuclear region in all three lines. Confocal microscopy however, indicated that most of the cells examined showed a homogeneous fluorescence distribution. The cells grown in monolayers were found to be thicker in the nuclear region suggesting that the observed increase in fluorescence intensity in the nuclear region in the images from epifluorescence microscopy was probably derived from fluorescence from an out-of-focus plane. Cells depleted of GSH with buthionine sulfoximine followed by treatment with mBCl showed significant fluorescence intensity resulting from nonspecific binding of this probe. These studies illustrate the need for measuring the rate of GSH conjugate export and for determining probe specificity, and emphasizes the need for using confocal techniques for the quantitative evaluation of the distribution of intracellular fluorescence. 相似文献
998.
999.
Chin‐Hang Shu Ko‐Jung Lin Bor‐Jiun Wen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(9):998-1002
The effects of culture pH on the production, molecular weight distribution and the bioactivity of polysaccharides produced by Agaricus blazei were evaluated by four pH‐controlled batch cultures. As the culture pH of each batch was controlled from 4.0 to 7.0, the maximum polysaccharide concentration increased from 561 to 1252 mg dm?3, but the average molecular weight of the polysaccharides decreased monotonically from 1080 kDa to 600 kDa, the relative amount of β‐glucan from 56% to 33%, and the TNF‐α release by macrophage cells from 1440 to 760 pg per 5 × 104 cells. Polysaccharides with higher molecular weights, β‐glucan contents and bioactivities were obtained in the submerged cultures of Agaricus blazei at lower culture pH but with lower yields. Copyright © 2004 Society of Chemical Industry 相似文献
1000.