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1.
This paper presents a method to compensate voltage sags with minimum energy injection for a series‐connected voltage restorer using a micro‐SMES. A circuit for extracting the fundamental symmetrical components from sag voltages and a minimum energy injection algorithm is described. Simulations of voltage sag compensation have been carried out using PSCAD/EMTDC for various faults. The simulation results confirm the validity of the proposed method and show the possibility of reducing the size of energy storage devices. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(3): 70–80, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10047  相似文献   
2.
Gas absorption accompanied by an instantaneous irreversible chemical reaction into laminar falling films of power-law liquids was studied theoretically. The convective-diffusion equations for a solute gas and a liquid-phase reactant were solved numerically and the numerical solution for the reaction factor was obtained as a function of the Graetz number, the concentration ratio, the diffusivity ratio and the power-law index of the liquid.  相似文献   
3.
Liquid viscosity and density of six binary mixtures of HFC-134a with glycols [ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (400), and polypropylene glycol (2000)] have been measured in the temperature range from 273 to 333 K. The viscosity was measured by a rolling-ball viscometer calibrated with standard liquids of viscosities and densities (JS5, JS10, JS20, and JS50). The density was measured with a glass pycnometer. The uncertainties of the measurements were estimated to be less than 3.4 % for viscosity and 0.04 % for density, respectively. An equation is given to represent the obtained viscosity values as a function of weight fraction and temperature.  相似文献   
4.
Measurements of saturated liquid viscosities and densities were performed on environmentally acceptable hydrochlorofluorocarbons (HCFCs), CH3CCl2F (HCFC-141b), CH3CClF2 (HCFC-142b; only for viscosity), CF3CF2CHCl2 (HCFC-225ca), and CClF2CF2CHClF (HCFC-225cb), using a capillary viscometer and a glass pycnometer in the temperature range from 273 to 353 K. The uncertainty in the measurement of viscosity is estimated to be 5% based on the comparison of the present data with those in the literature for HCFC-141b. An equation is given to represent our saturated liquid viscosity data as a function of temperature.  相似文献   
5.
To demonstrate three-dimensional architecture of regenerating axons growing through basal lamina tubes in cryoinjured nerve graft, backscattered electron (BSE) imaging in a scanning electron microscope (SEM) was used to visualize immunostained axons. Regenerating axons immunostained with an antibody against the 200 kD neurofilament protein (RT97) were clearly visualized in BSE images as bright components pursuing an irregular, often spiral course within the basal lamina tubes, and commonly branching within the tubes. The morphology of these structures corresponded closely to that of putative regenerating axons in SEM preparations following application of the potassium hydroxide-collagenase digestion method. The present approach, however, is a considerable improvement on the latter, providing three-dimensional information together with the identification of regenerating axons.  相似文献   
6.
UV-Vis spectroscopy was used to directly determine the concentration of Eu(Ⅱ) during electroreduction of Eu(Ⅲ) in hydrochloric acid medium. Electroreduction was carried out in a flow type electrolyzer with glassy carbon cathode at the constant potential of -800 mV vs. Ag/AgCl. The effects of oxygen and concentration of hydrochloric acid on the system were investigated. For 0.01 mol·L-1 hydrochloric acid, calibration curves for Eu(Ⅱ) absorption bands at 248 and 320 nm were constructed. Molar absorption coefficients were estimated to be 2016 and 648 L·mol-1·cm-1, respectively. The absorbance strongly decreased with decrease in pH of the solution, whereas concentration of chloride had only a negligible effect.  相似文献   
7.
This case report describes a case of carcinomatous peritonitis which showed a good response to the combination therapy of 5-FU, leucovorin and cisplatin. A 55-year-old man was admitted with complaints of meteorism due to ascites fluid. Ascitic examination showed a high concentration of CEA and CA19-9, and adenocarcinoma cells. Laboratory and radiological examination did not reveal the origin of the carcinoma, and laparotomy suggested an appendiceal origin. The combination chemotherapy with 5-FU, leucovorin and cisplatin was conducted for a total of 11 courses for 2 years with good QOL until his death. This therapy was suggested to be useful for inoperable carcinomatous peritonitis.  相似文献   
8.
In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g-1 for urea, 18 mg·g-1 for creatinine, and 20 mg·g-1 for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process.  相似文献   
9.
Summary The impact strength of polypropylene was improved by adding propylene-vinylsilane copolymer (PVS) in the presence of tris(triphenylphosphine)rhodium chloride(TPR). The impact strength of polyethylene at low temperature was also improved by adding TPR and PVS which is brittle at low temperature. These phenomena were not observed when polymers were mixed without TPR.  相似文献   
10.
Conductive papers were developed for preventing or reducing electromagnetic interference (EMI), and their shielding efficiency was evaluated. This type of conductive paper consists of wood pulp, synthetic pulp and metallized polyester fibers (0.5–2.0 mm long and 14 m in diameter) whose surfaces are coated with nickel alone (Ni-PET) or copper and nickel double layers (Ni-Cu-PET) by electroless plating. In this report, the effect of the characteristics of these metallized fibers, such as their conductivity, geometry and the concentration of fibers in paper, which lead to high efficiency for shielding effectiveness is discussed. For instance, one of the conductive papers (80 g/m2) which was prepared by mixing 40% Ni-Cu-PET and 60% synthetic polyethylene pulp showed over 40 dB shielding effectiveness between 10 MHz and 1 GHz.  相似文献   
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