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101.
The integrability conditions of the electromagnetic field equations in a continuum with defects and their wave solutions are found. The following dislocation effects on the electromagnetic wave propagation in a continuous medium are investigated: the change in the direction of the electromagnetic wave propagation in a continuous medium; the rotation of the polarization plane of electromagnetic field wave in a continuous medium; the excitation of longitudinal components of the electromagnetic wave in a continuous medium and the change in the electromagnetic wave intensity related to this phenomenon. The energy balance equation for the electromagnetic field in a continuum with a stationary distribution of dislocation is found and it is shown that an electromagnetic wave excites exciton modes localized at dislocations in the solid. 相似文献
102.
P. Edén G. Gustafson V. Khoze 《The European Physical Journal C - Particles and Fields》1999,11(2):345-350
A thorough verification of the distinct differences in the properties of quark and gluon jets is considered as one of the
most instructive tests of the basic ideas of QCD. In the real life experiments such a comparison appears to be quite a delicate
task and various subtle issues require further theoretical efforts. In this paper we discuss in detail the possibility to
extract the theoretically adequate information from the particle multiplicity patterns in three-jet events in annihilation.
Received: 8 June 1999 / Published online: 14 October 1999 相似文献
103.
Ed Kolodka Wen‐Jun Wang Shiping Zhu Archie E. Hamielec 《Macromolecular rapid communications》2002,23(8):470-473
Several novel poly(propylene)‐graft‐poly(ethylene‐co‐propylene) copolymers with isotactic poly(propylene) (PP) backbones and ethylene/propylene rubber (EPR) branches were synthesized. The thermomechanical properties of these samples were investigated using a dynamic mechanical analyzer. There appeared to be a critical EPR molecular weight above which a two‐phase system developed with EPR domains dispersed in a PP matrix. This domain formation gave an enhanced loss modulus compared to a commercial high impact PP product below 40°C. 相似文献
104.
J. Lüttke F. Moerck E. Ritsert Ed. Hirschsohn Sestini Campani E. Erdmann R. Stock O. Strobel M. C. Schuyten und J. Bougault 《Fresenius' Journal of Analytical Chemistry》1901,40(10):682-689
Ohne Zusammenfassung 相似文献
105.
Raphael Ed. Liesegang 《Colloid and polymer science》1941,97(1):96-99
Zusammenfassung Erh?hung der W?rmeempfindlichkeit der Sulfit-Novokain-L?sungen. PhotographischeWiedergabe der Lloyd-Schichtungen, welche darin
auftreten, wenn sie bei Vorhandensein eines Konzentrationsgef?lles erw?rmt werden.
Deren Bildung wird eingeleitet durch eine stufenweise Aufw?rtsbewegung von L?sung, die durch die randliche Erw?rmung ein etwas
geringeres spezifisches Gewicht erlangt hat. Dafür senkt sich die entsprechende Menge von kühlerer L?sung in der Mitte des
Rohrs nach unten und schiebt sich als klare Schicht unter die trübe. Es mu? jedoch zugegeben werden, da? damit der Mechanismus
der Schichtenbildung noch nicht in allen Einzelheiten gekl?rt ist.
Die notwendige Annahme der Konvektionen beim Zustandekommen der Lloyd-B?nderung schlie?t nicht aus, da? ihre Bedeutung nach
der Ausbildung stark zurücktritt. Verfestigung der Flüssigkeit durch Gelbildung kann gewisse Lloyd-B?nderungen dauernd erhalten. 相似文献
106.
107.
Ding S Dudley E Chen L Plummer S Tang J Newton RP Brenton AG 《Rapid communications in mass spectrometry : RCM》2006,20(24):3619-3624
Ginkgo biloba is one of the most popular herbal nutritional supplements, with terpene lactones and flavonoids being the two major active components. An on-line purification high-performance liquid chromatography/mass spectrometry (HPLC/MS) method was successfully developed for the quantitative determination of flavonoids and terpene lactones excreted in human urine after ingesting the herbal supplement. Satisfactory separation was obtained using a C18 capillary column made in-house with sample clean-up and pre-concentration achieved using a C18 pre-column with column switching. High selectivity and limits of detection of 1-18 ng/mL were achieved using a selected ion monitoring (SIM) scan in negative ion mode; the on-line solid-phase extraction (SPE) recovery of the active components in Ginkgo biloba determined in this study was greater than 75%. 相似文献
108.
Yu J Trieu BC Modlin EA Singh UN Kavaya MJ Chen S Bai Y Petzar PJ Petros M 《Optics letters》2006,31(4):462-464
Q-switched output of 1.1 J/pulse at a 2.053 microm wavelength has been achieved in a diode-pumped Ho: Tm: LuLF laser with a side-pumped rod configuration in a master-oscillator-power-amplifier (MOPA) architecture. This is the first time to our knowledge that a 2 microm laser has broken the joule per pulse barrier for Q-switched operation. The total system efficiency reaches 5% and 6.2% for single- and double-pulse operation, respectively. The system produces an excellent 1.4 times transform-limited beam quality. 相似文献
109.
In this study, a non-Fourier heat conduction problem formulated using the Cattaneo–Vernotte (C–V) model with non-homogeneous boundary conditions is solved with the superposition principle in conjunction with solution structure theorems. It is well known that the aforementioned analytical method is not suitable for such a class of thermal problems. However, by performing a functional transformation, the original non-homogeneous partial differential equation governing the physical problem can be cast into a new form such that it consists of a homogeneous part and an additional auxiliary function. As a result, the modified homogeneous governing equation can then be solved with solution structure theorems for temperatures inside a finite planar medium. The methodology provides a convenient, accurate, and efficient solution to the C–V heat conduction equation with non-homogeneous boundary conditions. 相似文献
110.
Ed Walsh Yuri Muzychka Patrick Walsh Vanessa Egan Jeff Punch 《International Journal of Multiphase Flow》2009
A segmented two phase slug/bubble flow occurs where a liquid and a gas are pumped into the same tube over a range of Reynolds numbers. This segmented two phase flow regime is accompanied by an increase in pressure drop relative to the single phase flow where only one fluid is flowing in a capillary. This work experimentally and theoretically examines the pressure drop encountered by the slug/bubble flow with varying slug lengths in mini channels. In the experimental work the dimensionless parameters of Reynolds number and Capillary number span over three orders of magnitude, and dimensionless slug length ranges over two orders of magnitude to represent flows typical of mini- and micro-scale systems. It is found, in agreement with previous work, that these dimensionless groups provide the correct scaling to represent the pressure drop in two phase slug/bubble flow, although the additional pressure drop caused by the interface regions was found to be ∼40% less than previously reported. 相似文献