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1.
Zygmunt Bak 《Czechoslovak Journal of Physics》2002,52(1):A25-A28
We consider RKKY interaction in a quasi 2D system with nonparabolic dispersion. In our paper we calculate the RKKY range function assuming the in-layer confinement via effective dimensionality approach. We show, that indirect magnetic exchange in our system can be modelled by the effective spectral dimension which equals one. 相似文献
2.
3.
The paper concerns several diagnostic techniques, which have been used in pulsed-power plasma experiments, i.e. Plasma-Focus and Z-Pinch devices, and which can be adapted to studies of Magnetic Confinement Fusion (MCF) facilities, e.g. Stellarators and Tokamaks. The application of Nuclear Track Detectors (NTDs) for time-integrated ion measurements in MCF experiments is described and the use of such detectors for time-resolved ion measurements is discussed. The application of special ?erenkov-type detectors for time resolved measurements of fast runaway electrons is considered. Also discussed is the use of selected nuclear reactions for measurements of fusion products, e.g. fast neutrons. 相似文献
4.
Piotr Bogusaw Mucha Witold Sadowski 《Mathematical Methods in the Applied Sciences》2005,28(15):1867-1880
The paper analyses long time behaviour of solutions of the Navier–Stokes equations in a two‐dimensional pipe‐like domain. The system is studied with perfect slip boundary conditions with arbitrary inflow conditions at infinity. The main results show the existence of global in time solutions and of an attractor for the dynamical system generated by the model. The paper also establishes an upper bound for the Hausdorff dimension of the attractor. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
5.
Robert J. Budzyński Sławomir Klimek Paweł Sadowski 《Communications in Mathematical Physics》1989,120(3):481-499
Motivated by the operator formulation of conformal field theory on Riemann surfaces, we study the properties of the infinite dimensional group of local biholomorphic transformations (conformal reparametrizations) of 1 and develop elements of its representation theory. 相似文献
6.
7.
Joseph R. Lakowicz Ignacy Gryczynski Henryk Malak Zygmunt Gryczynski 《Photochemistry and photobiology》1996,64(4):632-635
Abstract— We report the observation of two-photon excitation of an organic fluorophore with two different wavelengths, a phenomenon we refer to as two-color two-photon (2C2P) excitation. Ultraviolet emission of p -Merphenyl at 340 nm was observed when the sample was illuminated with both 375 and 750 nm pulses from a picosecond dye laser. The emission of p -terphenyl was about 100-fold and more than 1000-fold less for illumination at only 375 or 750 nm, respectively. Observation of the 2C2P signal required temporal and spatial overlap of the 375 and 750 nm pulses. The amplitude of the signal depended on the polarization of each beam. 2C2P excitation can have applications in fluorescence microscopy and elsewhere when spatially localized excitation is desirable. 相似文献
8.
The overall stability constantsK
1 andK
2 of NdNO
3
2+
and Nd(NO3)
2
+
complexes were determined (K
1=1.77;K
2=1.28) using an extraction method with tri-n-butyl phosphate as the extractant. The ratio 1/2 of the stepwise stability constants is discussed. It was established that the Nd(NO3)
2
+
complex was an outer-sphere ion pair.
Die Assoziation von Nitrat-Ion mit Nd3+
Zusammenfassung Mittels einer Extraktionsmethode wurden die StabilitätskonstantenK 1 undK 2 von NdNO 3 2+ - und Nd(NO3)+-Komplexen bestimmt (K 1=1.77;K 2=1.28; Tri-n-butylphosphat als Extraktionsmittel). Das Verhältnis 1/2 der stufenweisen Stabilitätskonstanten wird diskutiert. Es stellte sich heraus, daß der Nd(NO3)+-Komplex als ein Outer-Shere-Ionenpaar vorliegt.相似文献
9.
Organophosphorus pesticides are commonly used in both agricultural and residential settings. The widespread use of these chemicals makes it almost impossible for humans to avoid exposure. In order to determine background human exposure, there is a need for fast, reliable, and sensitive analytical methods. We have developed a sensitive method to quantify specific biomarkers of the organophosphorus pesticides acephate, azinphos, chlorpyrifos, coumaphos, diazinon, isazofos, malathion, methamidophos, parathion and pirimiphos or their O,O-dimethyl analogues in human urine, as their selective metabolites or as the intact pesticide. Isotopically labeled internal standards were used for eight of the analytes. The use of labeled internal standards in combination with high-performance liquid chromatography electrospray ionization–tandem mass spectrometry provided a high degree of specificity. Repeated analysis of urine samples fortified with high and low concentrations of the analytes gave relative standard deviations (RSD) of less than 10% for the analytes with an isotopically labeled standard. Analytes without isotopically labeled standards had higher RSD. For all compounds except methamidophos and acephate, the recoveries were greater than 70%. The limits of quantification for most of the analytes were in the range of 0.1 to 1 ng/mL. We detected concentrations of most of these pesticides and/or their metabolites in urine samples from non-occupationally exposed persons using our method. Our frequencies of detection for the analytes measured ranged from 1% to 98%. 相似文献
10.