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131.
The transverse polarization distribution of quarks h1(x) is computed in a confinement model, the chiral chromodielectric model. The flavor structure of h1, its Q2 evolution and Soffer's inequality are studied. The Drell-Yan double transverse asymmetry ATT is evaluated and found to be one order of magnitude smaller than some previous estimates which equated it to the double longitudinal asymmetry.  相似文献   
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133.
Summary We outline here the logical flow of papers that attack the problem of estimating the wave conditions in front of and at the Venetian littoral. We start from the determination of the wind fields, followed by that of the wave fields. The wave data are then transferred to the coast. We end by analysing the wave conditions inside the main inlet to the Venice lagoon. This paper gives a brief account of the logical flow of arguments from paper to paper, indicating the main results and outlining the robust structure of the overall research. We end with a discussion on the accuracy of the results, and with an indication of the possible lines for further research. Deceased in November 1995  相似文献   
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136.
Consider a graph GG with a minimal edge cut FF and let G1G1, G2G2 be the two (augmented) components of G−FGF. A long-open question asks under which conditions the crossing number of GG is (greater than or) equal to the sum of the crossing numbers of G1G1 and G2G2—which would allow us to consider those graphs separately. It is known that crossing number is additive for |F|∈{0,1,2}|F|{0,1,2} and that there exist graphs violating this property with |F|≥4|F|4. In this paper, we show that crossing number is additive for |F|=3|F|=3, thus closing the final gap in the question.  相似文献   
137.
We discuss two models in which a softening of the equation of state takes place due to the appearance of new degrees of freedom. The first is a hadronic model in which the softening is due to chiral symmetry restoration. In the second model the softening is associated with the formation of clusters of quarks in the mixed phase. We show that in the first case the bulk modulus is mainly dependent on the density, while in the mixed-phase model the bulk modulus strongly depends on the temperature and it is not vanishing due to the presence of two conserved charges, the baryon and the isospin one.  相似文献   
138.
In this Letter we report the first experimental observation of the double emittance minimum effect in the beam dynamics of high-brightness electron beam generation by photoinjectors; this effect, as predicted by the theory, is crucial in achieving minimum emittance in photoinjectors aiming at producing electron beams for short wavelength single-pass free electron lasers. The experiment described in this Letter was performed at the SPARC photoinjector site, during the first stage of commissioning of the SPARC project. The experiment was made possible by a newly conceived device, called an emittance meter, which allows a detailed and unprecedented study of the emittance compensation process as the beam propagates along the beam pipe.  相似文献   
139.
We demonstrate excitation and detection of nuclear magnetization in a nuclear quadrupole resonance (NQR) experiment with a parallel plate capacitor, where the sample is located between the two capacitor plates and not in a coil as usually. While the sensitivity of this capacitor-based detection is found lower compared to an optimal coil-based detection of the same amount of sample, it becomes comparable in the case of very thin samples and even advantageous in the proximity of conducting bodies. This capacitor-based setup may find its application in acquisition of NQR signals from the surface layers on conducting bodies or in a portable tightly integrated nuclear magnetic resonance sensor.  相似文献   
140.
We tackle the issue of the inviscid limit of the incompressible Navier–Stokes equations when the Navier slip-with-friction conditions are prescribed on impermeable boundaries. We justify an asymptotic expansion which involves a weak amplitude boundary layer, with the same thickness as in Prandtl’s theory and a linear behavior. This analysis holds for general regular domains, in both dimensions two and three.  相似文献   
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