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Horace P. Yuen 《Physics letters. A》1982,91(3):101-104
The importance of generalized quantum measurements in quantum optics and precision measurements is indicated. These measurements are formally realizable within conventional quantum mechanics and can often be interpreted as approximate simultaneous measurements of noncommuting observables. An uncertainty relation more stringent than the usual one is derived for these measurements. 相似文献
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We demonstrate theoretically and experimentally that secure communication using intermediate-energy (mesoscopic) coherent states is possible. Our scheme is different from previous quantum cryptographic schemes in that a short secret key is explicitly used and in which quantum noise hides both the bit and the key. This encryption scheme allows optical amplification. New avenues are open to secure communications at high speeds in fiber-optic or free-space channels. 相似文献
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George George Horace Jervis und E. W. Lucas 《Fresenius' Journal of Analytical Chemistry》1901,40(12):791
Ohne Zusammenfassung 相似文献
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A unique capillary die was designed which made possible the measurement of extrusion pressure at various locations along the capillary length. Entrance pressure drops, exit pressures, and other rheological characteristics were determined for the flow of poly(ethylene terephthalate) through this extrusion apparatus. The effect of die entrance angle, extrusion temperature, throughput rate and polymer molecular weight were considered. Two samples differing in molecular weight exhibited power-law behavior at shear rates below 1000s?1. The entrance pressure drops and exit pressures were observed to increase with increasing molecular weight; furthermore, at a specific temperature, both-increased with increasing shear rate. The values for entrance pressure drop obtained using Bagley analysis were consistently higher than those obtained from direct measurements. 相似文献
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Horace Grover 《Experimental Mechanics》1972,12(5):250-256
It is impossible to find, for a specific design concern, fatigue information that is entirely adequate for an exact quantitative evaluation. Some of the approaches available for approximate design estimates are described to illustrate the problems that may occur and the considerations important in using available fatigue information in design. 相似文献
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A unique retainer/transparent quartz die assembly was designed and fabricated to fit on a melt extruder. It permitted visualization of polymer flow behavior during melt spinning. Tracer particles were mixed with polymer chips prior to extrusion. A laser beam was directed through a lens system and used to illuminate the tracer particles in the melt only in a thin, vertical cross section of the transparent quartz die. Streak photography was used to determine the cross-sectional velocity distribution of the melt as it passed through the die. 相似文献
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Horace R. Byers S. Krishnama Chary 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1963,14(5):428-433
Zusammenfassung In die Theorie der homogenen Keimbildung wird für die Oberflächenspannung kleiner Tröpfchen eine vonTolman vorgeschlagene Korrektur eingeführt, die kleinere kritische Keimradien ergibt. Diese Verkleinerung ist zwar abhängig von Temperatur und Übersättigung, jedoch praktisch konstant oberhalb vierfacher Übersättigung. Die hier berechneten Werte kritischer Keimradien, der Molekülzahlen pro kritischen Keim, der Anzahl kritischer Keime sowie der Keimbildungsrate mit und ohne Korrektur sind in den Tabellen 1 und 2 dargestellt; Keimzahl und Keimbildungsrate sind zudem in Figur 1 für die Temperatur 283,2° K graphisch dargestellt. Um Vergleiche mit den Ergebnissen von Wolkenkammer-Versuchen anstellen zu können, wird der «Schwellenwert der Kondensation» neu definiert unter Einschluss des Korrekturterms; die so erhaltenen Werte sind in Tabelle 3 aufgeführt. Die Übereinstimmung mit dem Experiment ist besser als im Fall, in dem lediglich die Oberflächenspannung der ebenen Oberfläche in Rechnung gesetzt wird.
This research was supported by Grant G-22292 (Cloud Physics Research) from the National Science Foundation. 相似文献
This research was supported by Grant G-22292 (Cloud Physics Research) from the National Science Foundation. 相似文献
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Merritt?C.?Helvenston Vladimir?N.?NesterovEmail author Horace?J.?Jenkins 《Journal of chemical crystallography》2005,35(2):113-118
Synthesis and X-ray structural investigations have been carried out for the two title compounds C14H10N2O (3a) and C22H26N2O (3b). Compound 3a crystallizes in the monoclinic space group P21/c, with a = 3.843(1) Å, b = 24.618(5) Å, c = 11.318(2) Å, = 92.61(3), V = 1069.7(4) Å,3 and Z = 4. Compound 3b crystallizes in the triclinic space group P-1, with a = 9.004(2) Å, b = 9.447(2) Å, c = 11.713(2) Å, = 76.70(3), = 83.12(3), = 82.16(3), V = 956.5(3) Å,3 and Z = 2. Both stilbazole derivatives have Z-geometry about the ethylene bridge which links the heterocyclic and aromatic rings. The molecular skeleton of 3a is slightly non-planar: the dihedral angles between the acrylonitrile linkage and the pyridine ring, and between this linkage and the p-hydroxyphenyl ring are 7.2(2) and 4.1(2), respectively. The molecular skeleton of 3b is less planar: the values of similar dihedral angles are 17.0(2) and 20.8(2), respectively. In the crystal of 3a, the molecules are packed in stacks along the a axis with head-to-head orientation. Intermolecular hydrogen bonds O=H s N and C=H s N link molecules into sheets parallel to (100) plane. In the crystals of 3b, the molecules have a head-to-tail orientation and intermolecular hydrogen bonds O=H s N link the molecules into infinite chains along [01-1] direction. 相似文献