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11.
Abstract— A method of preparation of positive O films with the tilt angle of the optic axis continuously controlled in the range 0–90° is proposed. It is based on the use of reactive mesogens and alignment materials that provide a wide range of pretilt angles. The method developed allows for further improvement in the viewing‐angle characteristics of LCDs with O compensation films.  相似文献   
12.
Abstract— The fabrication and demonstration of field‐sequential‐color (FSC) LCDs using modules of narrow‐gap twisted‐nematic (NTN) LCDs with and without doping of newly synthesized PγCyD‐ZrO2 nanoparticles is reported. Two types of FSC‐LCDs are demonstrated: one is a direct multiplexed NTN‐LCD and the other is TFT driven. The advantages of FSC‐LCDs include their high legibility even under direct sunlight, and the mechanism for the doping of nanoparticles in LCDs is discussed.  相似文献   
13.
151Eu-Mössbauer spectroscopic and powder X-ray diffraction (XRD) study has been performed for the EuyM1−yO2−x (M = Th and U) systems over the entire composition range of 0 ≤ y ≤ 1.0. The XRD results of the Eu-Th system showed that a very wide defect-fluorite (DF) type phase in which oxygen vacancies (VO) are disordered (x = y/2) is formed for 0 ≤ y < 0.5 and that two-phase regions sandwitching a narrow C-type (C) single phase around y ≈ 0.8 appear for 0.5 < y < 0.8 (DF + C) and 0.82 < y < 1.0 (C + B-type (monoclinic) Eu2O3). The Mössbauer results show that the isomer shifts (ISs) of Eu3+ in this system smoothly increase with Eu composition, y. The decrease of average coordination number (CN) of O2− around Eu3+ with increasing y (CN = 8 − 2y) (x = y/2) results in the decrease of the average EuO bond length, which is due to the decrease of repulsion force between O2− anions. This result confirms that the IS of Eu3+ correlates well with the average EuO bond length in oxide systems. For the Eu-U system, the lattice parameter, a0, of the system decreases almost linearly with y, in accordance with the calculated a0 versus y curve for the oxygen-stoichiometric (i.e. x = 0) fluorite-type dioxide (CN = 8). The ISs of Eu3+ in this composition range remain almost constant around 0.5 mm/s, which is comparable to those of pyrochlore oxides (Eu2Zr2O7 and Eu2Hf2O7 (y = 0.5)) with O2−-eight-fold coordinated Eu3+(CN = 8).  相似文献   
14.
Noncontact energy transfer systems are widely used in industrial material handling systems. This paper proposes a new noncontact energy transfer system using a tuned pickup coil and an immitance converter inductively coupled to a parallel transmission line excited by a high‐frequency constant‐current source. In a noncontact energy transfer system which supplies continuous energy to movers by electromagnetic induction, the efficiency is low owing to low excitation impedance because of the wide air gap of the magnetic core in the pickup coil. The excitation impedance can be increased by the resonance with a capacitor connected parallel to the pickup coil. The resonant pickup coil works as a high‐frequency constant‐current source for the load. We propose using an immittance converter to transform the high‐frequency constant‐current source into a high‐frequency constant‐voltage source. Then, the high‐frequency constant‐voltage source is rectified into a constant‐voltage dc source, and supplies power to an inverter for motor driving. In this paper, the configuration of this new noncontact energy transfer system and its characteristics are described. The experimental results and simulation waveforms are also described. © 2001 Scripta Technica, Electr Eng Jpn, 136(4): 58–64, 2001  相似文献   
15.
As a part of our studies on paralytic shellfish poison (PSP) accumulation kinetics in bivalves, short-necked clam Tapes japonia was experimentally contaminated with PSP by being fed with the toxic dinoflagellate Alexandrium tamarense for 2, 4, 6, 8 and 10 days, and the processes of PSP accumulation and bioconversion were investigated: the toxicity level was determined by mouse bioassay and toxin components were identified by high-performance liquid chromatography (HPLC). The strain of A. tamarense used in this study possessed a specific toxicity of 186.7 +/- 81 (mean +/- S.D., n = 5) x 10(-6) MU/cell. Total toxin concentration of this strain was 140.4 +/- 61 (mean S.D., n = 5) fmol/cell. The toxicity level of short-necked clams increased almost in parallel with the abundance of A. tamarense, reaching 1.8, 3.2, 3.8, 3.5 and 4.6 MU/g meat for 2, 4, 6, 8 and 10 days of feeding, respectively. The accumulation rates of PSP toxins, which are the ratio of the total amount of toxins accumulated in the bivalves to the estimated intake in each feeding experiment, were 7.5, 8.1, 5.7, 4.2 and 4.4% for 2, 4, 6, 8 and 10 days, respectively. At the end of each exposure period, many undigested algal cells were found in pseudofeces under microscopic observation. There was a remarkable difference in the relative proportions of the predominant toxin components between A. tamarense and short-necked clams. The most notable difference was the change in the relative amounts of C2 (carbamoyl-N-sulfo-11beta-hydroxysaxitoxin sulfate), GTX1 and GTX 4 during the first two days. In the toxic bivalves, the amount of C2, which is dominant in A. tamarense, decreased to below half a percent after being ingested. Subsequently, the amount of GTX1 in the shellfish meat reached 50.1 mol%, while that of GTX4 decreased to about half of that in A. tamarense. As for the configuration of 11-hydroxysulfate, PSP components in A. tamarense exist almost exclusively as beta-epimers (GTX3, GTX4, C2 and C4), accounting for 72.8 mol% of the total. This contrasts with the case of the short-necked clams, where the beta-epimers represented 25.8, 33.8, 30.8, 36.8 and 28.5 mol% of the total after 2, 4, 6, 8 and 10 days, respectively. PSP components seemed to be converted rapidly at an early stage of the feeding of A. tamarense.  相似文献   
16.
The anodic oxidation of neodymium was investigated by the galvanostatic technique in Na2-HPO4 - ethylene glycol solution. According to the combination of measurments of ac capacity and of specular reflectivity, we obtained a refractive index for the oxide films as a function of wavelength and the value of apparent dielectric constant of the films for which sesquioxide Nd2O3 was assumed to have been produced. It was found that the film thickness could be determined from the wavelength of both maximum and minimum specular reflectivities due to interference, and that a linear relationship existed between the film thickness and the formation voltage. The slope of this linear line was 10.0Å V?1 or a mean field of 1.00 × 107 V cm?1 at 1 mA cm?2. The apparent current efficiency estimated from the thickness of the film vs passed charge plots scarcely depended on latter and its value was about 0.52, assuming that the film composition was Nd2O3.  相似文献   
17.
In the present study,a computational fluid dynamics work was performed to investigate the occurrence of the shock wave by condensation in supersonic moist air jet.The unsteady,compressible axisymmetric Navier-Stokes equation is solved by TVD(Total Variation Diminishing) scheme in this study.The numerical simulations have been performed for low pressure ratio and various humidities.The results show the occurrence of the shock wave in supersonic moist air jet for a low pressure ratio when Mach disk does not occur,depending on humidity of the air.  相似文献   
18.
When the underexpanded supersonic jet impinges on the obstacle, it is well known that the self-induced flow oscillation occurs. This oscillation depends on the pressure ratio in the flowfield, the position of an obstacle and is related with the noise problems of aeronautical and other industrial engineering. The characteristic and the mechanism of self-induced flow oscillation, have to be clarified to control various noise problems. But, it seems that the characteristics of the oscillated flowfield and the mechanism of an oscillation have to be more cleared to control the oscillation. This paper aims to clarify the effect of the pressure ratio and the obstacle position and the mechanism of self-induced flow oscillation by numerical analysis and experiment, when the underexpanded supersonic jet impinges on the cylindrical body. From the result of this study, it is clear that occurrence of the self-induced flow oscillation depends on the pressure balance in the flowfield.  相似文献   
19.
Recently, there has been remarkable increase in the survival rate in cases of biliary atresia (BA). However, long-term survivors are as yet a small population. Of the total of 152 patients undergoing surgery for BA during the period from 1969 to 1995 in our institution, 39 of them were operated on more than 20 years ago with follow up for all but one of these, who can no longer be accounted for. Six are still alive, 1 male, and 5 females, two cases being of type I BA, and the other 4 of type III and 1 is unaccounted for. The prognosis of these individuals was clinically evaluated. At the present time, none of them is receiving hospital care, but 3 have experienced sequelae. Two patients required partial splenic embolization (PSE), endoscopic infusion sclerotherapy (EIS), and/or gastroesophageal decongestion and splenectomy (Hassab's operation) (Hassab 1967) for hypersplenism and/or portal hypertension. The other has needed hospital care for recurrent cholangitis. Laboratory investigations revealed a serum total bilirubin (TB) of less than 1.0 mg/100 ml in 3 of the 5 patients for which samples could be obtained, between 1.0 and 2.0 mg/100 ml in 1, and in excess of this in the remaining case. The 1-alanine 2 oxoglutarate aminotransferase (ALT) level was within the normal range in only 1, and was mildly to moderately elevated in 4. The white blood cell count (WBC) was less than 3,000/microliter and the platelet count was less than 10 x 10(4)/microliter in 1, and within the normal ranges in the other 4 patients. The results thus indicate that occult and progressive liver damage may occur in long-term survivors of BA.  相似文献   
20.
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