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341.
PURPOSE: Renal sonography is an accepted primary imaging modality for evaluating the pediatric urinary tract. We report a new sonographic finding associated with vesicoureteral reflux (VUR). METHODS: Ten patients underwent sonographic evaluation of the kidneys and were noted to have intermittent renal collecting system dilatation that expanded and contracted during real-time scanning. These patients were further evaluated with voiding cystourethrography. RESULTS: All 10 patients were proven to have VUR on the side of the sonographic abnormality. Four patients had bilateral VUR for a total of 14 refluxing renal units. Of these 14 renal units, 1 was sonographically normal. Five of the 14 renal units had grade V VUR that required surgical reimplantation of the ureter. CONCLUSIONS: This new finding of intermittent renal collecting system dilatation may become an important predictor of VUR. The finding warrants further evaluation even when detected in patients not suspected of having VUR who are undergoing renal sonography for other reasons. 相似文献
342.
The influence of acidity, alkyl chain length of alcohols, synthesis temperature and time on the molecular sieve synthesis by adding alcohols to the system for the SBA-1 synthesis were studied. Upon increasing the concentration of alcohols (CmH2m+1OH) in the mixture of tetraethyl orthosilicate (TEOS), cetyltriethylammonium bromide (CTEABr), HCl and H2O, highly ordered P63/mmc and p6mm phases were formed when m = 2 and 3 ≤ m ≤ 6, respectively. The amount of HCl was an important factor for the phase-selection under acidic conditions. 相似文献
343.
T Nakatani H Anai K Araki Y Wakisaka Y Taenaka E Tatsumi H Akagi T Masuzawa Y Baba K Eya 《Canadian Metallurgical Quarterly》1994,40(3):M723-M727
Right ventricular (RV) function is a limiting factor in maintaining systemic circulation with circulatory assist. There is, however, no easy way to institute RV assist, such as the intraarterial axial flow pump (Hemopump) used for left heart assist. In this study, the feasibility and hemodynamic effect of intravenous use of an axial flow pump was examined. A pump system was developed with an outflow cannula and an impeller that were newly designed for intravenous insertion with a Hemopump driving system. The pump system characteristics using goat blood at a hematocrit of 26% indicated that maximum flow at a pressure differential against 40 mmHg is 3.2 l/min at a pump speed of 28,000 rpm. The pump was tested in adult goats by intravenous insertion through a 14 mm, low porosity graft anastomosed to the infrarenal inferior vena cava. The pump was advanced until the tip of the cannula was positioned at the main pulmonary artery, using balloon catheter guidance under fluoroscopy. RV assistance was evaluated by pressure tracing, and aortic flow (AF) measured by electromagnetic flowmeter under 1) induced pulmonary stenosis (PS), and 2) electrically induced ventricular fibrillation (VF) in combination with left heart assist. Under PS, right atrial pressure decreased from 11 to 2 mmHg and AF increased from 1.0 to 4.1 l/min after initiation of the pump. Under VF, AF and aortic pressure were 2.6 l/min and 78 mmHg, respectively, with left ventricular assist. After initiation of the pump, they increased to 4.0 l/min and 98 mmHg, respectively. In chronic experiments using three adults goats for up to 48 hr, levels of plasma hemoglobin and platelet counts were maintained within an acceptable range. There was no prominent damage to the hearts. These data suggest that an axial flow pump introduced by an intravenous approach without thoracotomy is feasible and provides sufficient right heart assist. 相似文献
344.
N. Sato T. Haruyama K. Kuroda M. Ohashi T. Shintomi D. Tatsumi C. Taylor T. Tomaru A. Yamamoto 《低温学》2003,43(7):425-429
We measured forces applied by an actuator with a YBa2Cu3O7 (YBCO) film at near 77 K for the Large-scale Cryogenic Gravitational-wave Telescope (LCGT) project. An actuator consisting of both a YBCO film of 1.6 μm thickness and 0.81 cm2 area and a solenoid coil exerted a force of up to 0.2 mN on a test mass. The presented actuator system can be used to displace the mirror of LCGT for fringe lock of the interferometer. 相似文献
345.
A LaGaO3-based electrochemical sensor in the amperometric mode was demonstrated as highly sensitive to NO in the temperature range 500-700°C. Sensor performance was found dependent on the Ni doping of LaGaO3. Using optimized electrode materials, highest sensitivity was achieved as high as 2409 µ A/decade (at 550°C) when Ni doping to electrolyte was 7 mol%. The selectivity of the sensor was found very high to NO with respect to the typical coexisting gases in the exhaust environment. The sensing principle was observed to follow the mixed potential behavior. 相似文献
346.
Ronald R Navarro Rosvic C Navarro Catalino G Alfafara Rex B Demafelis Kenji Tatsumi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(10):1125-1130
Organic matter (chemical oxygen demand, COD) removal with decolorization in waste distillery slops and copper removal in a semiconductor industry wastewater were achieved in a single step mixing and precipitation/coagulation treatment system. The process utilized the complementary properties of the positively charged copper ions in semiconductor wastewater and net negative charge of melanoidin (organic chromophoric pollutant) in distillery slops to mutually neutralize each other. Copper ions served as coagulant for slops and melanoidin served as precipitant for copper. The volumetric ratio of the wastewater and pH were optimized to attain maximum removal of organic matter and copper. The optimum volumetric ratio for the evaluated semiconductor wastewater to distillery slops was found to be 2–3 with an equilibrium pH of around pH 6. At optimum conditions, average removals of COD and copper were 86% and 92%, respectively, in an actual and undiluted system. Decolorization efficiency using the diluted distillery slops was 89%. The process can be considered an effective pretreatment procedure for simultaneous gross removal of copper and color/COD, particularly in highly concentrated waste streams. Copyright © 2005 Society of Chemical Industry 相似文献
347.
Yoshino A. Kumagai K. Hamatake N. Tatsumi T. Onishi H. Kurosawa S. Okumura K. 《Electron Device Letters, IEEE》1996,17(3):106-108
We present experimental results concerning the propagation delay time of the 0.35 μm CMOS gate chains (inverter, 3NAND, and 3NOR) fabricated on low-dose SIMOX substrates with and without the N-well formed underneath the buried oxide layer in the PMOS region. Using such experimental data as the capacitance voltage characteristics of the buried oxide layer, and the enhanced PMOS transistor drivability due to the negative back bias effect, we clarify the most essential factor of the high-speed performance of the CMOS/SIMOX circuits fabricated on a low-dose SIMOX substrate 相似文献
348.
Reisuke Doi Keiji Uchikoshi Hikari Beppu 《Journal of Nuclear Science and Technology》2016,53(10):1554-1562
To determine the equilibrium constant for ferroselite (FeSe2(cr)) dissolution reaction, FeSe2(cr) solubility experiments were performed at 298 ± 1 K from both the over- and under-saturation directions with Fe–Se precipitates that were aged at 348 K. X-ray diffraction (XRD) analysis detected only FeSe2(cr) as the Se solid phase in the equilibrated precipitates. The Eh values of the equilibrated suspensions ranged from ?188.6 to ?4.9 mV vs. standard hydrogen electrode (SHE) and the pH values ranged from 6.00 to 8.76. Based on the available thermodynamic data, Se42? and Fe2+ are thermodynamically stable within this Eh–pH range. Agreement between the solubility data obtained from the over- and under-saturation directions lends credence to the attainment of equilibrium at 298 ± 1 K. The thermodynamic interpretations using the specific ion interaction theory (SIT) model showed that Eh values and the concentrations of Se and Fe are well represented by the 2FeSe2(cr) solubility reaction (2FeSe2(cr) ? 2Fe2+ + Se42? + 2e?) with log10K○ = ?17.09 ± 0.28. The obtained log10K○ value falls within the uncertainty limits of the log10K○ value calculated from the available thermodynamic data. 相似文献
349.
Masato Tabuchi Akio Yamamoto Tomohiro Endo Masahiro Tatsumi 《Journal of Nuclear Science and Technology》2016,53(11):1858-1869
A new technique to reduce discretization errors for ray tracing in the method of characteristics (MOC) is proposed focusing on depletion calculations of single and multi-assembly geometries. In order to efficiently carry out depletion calculations, a calculation scheme using the superhomogenization (SPH) method can be used. However, the discretization errors are caused by changes of neutron sources and total cross sections according to a depletion. This fact means that improvement of accuracy cannot be expected by the calculation scheme with the SPH method when changes of the above parameters are significant. In order to mitigate this problem, a new approach is developed. In the new approach, the discretization errors are reduced by minimizing a variance of a certain parameter which is composed of a ratio of neutron source to total cross section. The verification results suggest that accuracy is degraded by the SPH method as expected especially in a geometry where neutron sources and total cross sections are drastically changing through a depletion. On the other hand, the new approach gives more accurate results compared to the conventional MOC in all calculation cases. Consequently, improvement of calculation efficiency by the new approach is confirmed. 相似文献
350.
Tatsumi Ishihara Ken Tominaga Junji Hyodo Maki Matsuka 《International Journal of Hydrogen Energy》2012
Pr1.91Ni0.71Cu0.24Ga0.05O4 (PNCG) thin film with few 100 nm thickness was prepared on polycrystalline MgO substrate with pulsed laser deposition (PLD) method. The prepared film was dense and uniform, and formation of Pr2NiO4 phase was observed after a post annealing treatment. Electrical conductivity was significantly changed in the film and increase in conductivity was observed when the film thickness was 320 nm. However, the conductivity decreased with decreasing the film thickness less than 300 nm and Hall coefficient measurements suggested that the electronic hole concentration increased, however its mobility decreased in PNCG film because of the expanded lattice. Increased conductivity in the PNCG film with 320 nm could be explained by the increased amount of electronic hole and its high mobility. XPS measurement also showed that Pr and Ni were an oxidized state comparing with that in bulk and so excess oxygen may be introduced in the PNCG thin film by charge compensation. 相似文献