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1.
A rare case of left atrial dissection after mitral valve replacement is reported. Low output syndrome developed in the immediate postoperative period. Cardiac catheterization showed marked elevation of the pulmonary wedge pressure, and left ventriculography revealed massive paraprosthetic leakage with left atrial dissection. At the reoperation, the dissecting cavity was successfully closed from inside the left atrium under cardiopulmonary bypass. We consider this complication another variation of an atrioventricular discontinuity after mitral valve replacement.  相似文献   
2.
Both calling behavior and titer of (Z)-9-hexadecenal (Z9-16: Al), the major sex pheromone component ofHelicoverpa assulta, in pheromone glands showed distinct diel periodicity, and these two were synchronous. Calling was most actively performed and the pheromone titer reached a maximum from 2 to 6 h after lights-off. During photophase, no calling was shown and only a relatively small amount of Z9-16:A1 was detected. However, there was a time lag of a few days between peak calling activity and maximum pheromone titer. The pheromone titer was maximal from age 1 day to age 5 days and thereafter decreased while calling was most actively performed after age 3 days. Titers of three minor components, hexadecenal, (Z)-11-hexadecenal, and (Z)-9-hexadecenyl acetate, showed similar daily fluctuation patterns to that of Z9-16:Al, but relative to the titer of Z9-16:Al, the titer of the two aldehyde components remained relatively constant whereas that ofZ9-16:Ac increased in the late scotophase.  相似文献   
3.
We have prepared a large number of crystals of cuprous oxide (Cu2O) by various procedures. Photoluminescence spectra of these crystals were studied to examine the concentration of defects, especially copper vacancy VCu to seek favourable conditions for growing Cu2O crystal. High-quality single crystals of Cu2O were prepared by the floating-zone melting method in air. Several synthetic crystals (specimens FA, FZ and GZ) and also a natural crystal were studied by X-ray analysis, inductively coupled plasma spectroscopy analysis, optical absorption, photoluminescence, photoconductivity and cyclotron resonance absorption, photoluminescence, photoconductivity and cyclotron resonance absorption to characterize their optical and electrical qualities. The best values of mobility and scattering time of photocarriers at T = 4.2 K are estimated to be h1.8 × 105 cm2 V–1 s–1 and h60 ps for positive holes, and 1.3 × 105 cm2 V–1 s–1 and 70 ps for electrons in Cu2O. Further, we report preliminary experimental results on transport property of crystals also of cupric oxide (CuO) purified by the floating-zone melting method.  相似文献   
4.
A new 4T2C pixel circuit formed on a silicon substrate is proposed to realize a high‐resolution 7.8‐μm pixel pitch AMOLED microdisplay. In order to achieve high luminance uniformity, the pixel circuit compensates its Vth variation of the MOSFET for the driving transistor internally by using self‐discharging method. Also presented are 0.5‐in Quad‐VGA and 1.25‐in wide Quad‐XGA microdisplays with the proposed pixel circuit.  相似文献   
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In this paper we consider a deductive question-answering system for relational databases as a logic database system, and propose a knowledge assimilation method suitable for such a system. The concept of knowledge assimilation for deductive logic is constructed in an implementable form based on the notion of amalgamating object language and metalanguage. This concept calls for checks to be conducted on four subconcepts, provability, contradiction, redundancy, independency, and their corresponding internal database updates. We have implemented this logic database knowledge assimilation program in PROLOG, a logic programming language, and have found PROLOG suitable for knowledge assimilation implementation.  相似文献   
7.
T. Sadahiro  S. Yamaya  K. Shibuki  N. Ujiie 《Wear》1978,48(2):291-299
Ti(N, C, O), which has been chosen as a coating material for cutting tool inserts, was prepared on cemented carbides and high speed steels by chemical vapour deposition via a gas mixture of TiCl4, H2, N2, CH4 and CO2 under reduced pressure. This coating layer is characterized by fine grain size and freedom from porosity. The coated tool inserts show excellent cutting performance.  相似文献   
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9.
High tensile strength fibers of poly[(R)‐3‐hydroxybutyrate‐co‐(R)‐3‐hydroxyhexanoate] [P(3HB‐co‐3HH)], a type of microbial polyesters, were processed by one‐step and two‐step cold‐drawn method with intermediate annealing. Thermal degradation behaviors were characterized by differential scanning calorimeter and gel permeation chromatography measurements. Thermal analyses were revealed that molecular weights decreased drastically within melting time at a few minute. One‐step cold‐drawn fiber with drawing ratio of 10 showed tensile strength of 281 MPa, while tensile strength of as‐spun fiber was 78 MPa. When two‐step drawing was applied for P(3HB‐co‐3HH) fibers, the tensile strength was led to 420 MPa. Furthermore, the optimization of intermediate annealing condition leads to enhance the tensile strength at 552 MPa of P(3HB‐co‐3HH) fiber. Wide‐angel X‐ray diffraction measurements of these fibers suggest that the fibers with high tensile strength include much amount of the planer‐zigzag conformation (β‐form) as molecular conformation together with 21 helix conformation (α‐form). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41258.  相似文献   
10.
In many industries, there are applications that require the joining of stainless steel and copper components; therefore, the welding of dissimilar stainless steel/copper joints is a common process. For this investigation, the optimal brazing conditions and suitable filler metals for laser brazing of stainless steel/copper lap joints were studied. Tensile shear force increases with increases in the laser spot diameter or in the laser irradiation angle, which is associated with increased bonding width; however, as bonding width approaches 2 mm, tensile shear force reaches a saturated value due to fracturing at the HAZ of the Cu base plate. In order to obtain joints with high tensile shear strength, laser brazing was optimized by using Cu–Si-based filler metal under the following conditions: laser power, 4 kW; spot diameter, 3 mm; laser irradiation angle, 80°; irradiation position shift, 0.6 mm; brazing speed, 0.30 m/min; and filler metal feed speed, 0.30 min. Concerning filler metals, it was found that the Ni–Cu type showed relatively large tensile shear force even at high welding speeds in comparison with those of the Cu–Si, Cu, Cu–Ni, Ni–Cu and Ni types, respectively.  相似文献   
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