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This paper reports on a new cross-equipment study on the charging phenomena of solid insulators, evaluating the influence of charging on high-voltage equipment such as gas insulated switchgear (GIS), oil-immersed transformers, gas-insulated transformers and high-voltage vacuum-insulated equipment. New parameters of normalized charge density and surface resistance are introduced to consistently explain all the characteristics of the surface charge density on solid insulators and the decay time constant of the accumulated charges between the equipment. The results show that the surface charge density and the decay constant decrease as the surface resistance of the insulators is lowered. Combinations of insulating media of solid insulators and fluids (gas or liquids) are discussed for GIS and oil-immersed transformers in terms of the relation between the relative permittivity and the volume resistivity. The decay time constant of the accumulated charges is generally dominated by the insulating media of a fluid like oil which has lower volume resistivity than solid insulators in cases like transformers. However, the time constant is determined by the resistivity of the solid insulator rather than the fluid (gas) for GIS. Furthermore, it is suggested that low resistivity coatings on solid insulators are effective in suppressing the charge accumulation on the insulators. These new cross-equipment studies on the charging phenomena are an effective approach to reliable insulation design especially when downsizing high-voltage equipment. Index Terms--Cross-equipment study, charge accumulation, solid insulators, GIS, oil-immersed transformers, gas-insulated transformers, high-voltage vacuum-insulated equipment, charge density, surface resistance, decay time constant.

Superconducting calorimeters have been developed using transition edge sensors for use in industrial x-ray microanalysis.

The effect of Al doping on crystalline and optical properties of semipolar (1-101)GaN was investigated. The samples were grown on a patterned (001)Si substrate by selective metal-organic vapor phase epitaxy. The x-ray analyses showed that the strain in the (1-101)GaN layer is reduced substantially by the Al doping. Moreover, the cathode-luminescence (CL) intensity of the band edge emission band was enhanced and the linewidth became narrow. The CL images showed the reduction of dislocation density. These results show that the small amount of Al atoms in GaN improves the crystalline and optical properties. The results are attributed to the dislocation pinning and solution hardening effect due to Al atoms. [ABSTRACT FROM AUTHOR]

A 73-year-old man with aortic regurgitation was examined by 123I-alpha-methyl-p-iodophenylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) in 1995. Myocardial accumulation was not evident on either the early or the delayed image obtained 15 minutes and 3 hours, respectively, after injecting 123I-BMIPP. Flow cytometric analysis of CD36 expression in monocytes and platelets identified a type I CD36 deficiency. The patient was hospitalized for severe heart failure in 1999. Upon admission, the cardiothoracic ratio on chest X-rays was 73%, and the left ventricular end-diastolic diameter on echocardiograms was enlarged to 77 mm. On the second day, we performed 123I-BMIPP myocardial SPECT. Myocardial accumulation was evident in the delayed, but not in the early image. We repeated 123I-BMIPP myocardial SPECT on the 10th day after admission. Myocardial accumulation was evident on both early and delayed images. 99mTc-tetrofosmin myocardial SPECT was immediately performed after 123I-BMIPP myocardial SPECT to distinguish myocardial from pooling images in the left ventricle, but, because the images from both 99Tc-tetrofosmin and 123I-BMIPP myocardial SPECT were idential, we considered that the 123I-BMIPP myocardial SPECT images reflected the actual myocardial condition. The CD36 molecule transports long-chain fatty acid (LCFA) on the myocardial membrane, but 123I-BMIPP scintigraphy does not show any myocardial accumulation in patients with type I CD36 deficiency, indicating that myocardial LCFA uptake occurs through CD36 on the human myocardial membrane. Even though our patient had type I CD36 deficiency, BMIPP was uptaken by the myocardium during heart failure, suggesting a variant pathway on the human myocardial membrane for LCFA uptake. [ABSTRACT FROM AUTHOR]

A 55-yr-old man underwent surgery. Soon after the procedure was finished, the patient complained of chest pain, and the electrocardiogram showed increase in the ST-segment in some leads. Emergency angiography showed normal coronary arteries, but there was asynergy in the left ventricle, and delayed filling of contrast medium was observed in the LCA. An intracoronary infusion of isosorbide dinitrate did not improve the delayed filling of contrast medium or ST segment increase in the electrocardiogram. Soon after nicorandil was injected into the LCA, the patient's symptoms, electrocardiogram, and delayed filling of contrast medium dramatically improved. On the second day, initial imaging by 123I-BMIPP myocardial SPECT showed a moderate increase in tracer uptake in the apico-anteroseptal region and a moderate decrease in tracer uptake in the lateral region, in which the first left ventriculography showed akinesis, and delayed imaging revealed a moderate increase in tracer uptake in the apical region and a high washout of 123I-BMIPP in the anteroseptal and lateral regions. On the sixth day, initial imaging by 123I-BMIPP myocardial SPECT showed a moderate decrease in tracer uptake in the apical and lateral regions and a mild decrease in tracer uptake in the anteroseptal region, and delayed imaging revealed a moderate increase in tracer uptake in the apical region and a high washout of 123I-BMIPP in the anteroseptal and lateral regions. By the 30th day, 123I-BMIPP myocardial SPECT had normalized. We consider that these dynamic changes in 123I-BMIPP myocardial SPECT imaging may reflect metabolic changes in fatty acids in the ischemic state, the size of the triacylglycerol pool, and the degree of turnover in the triacylglycerol pool. [ABSTRACT FROM AUTHOR]