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81.
The perturbation of the generator of a Borel right process by a signed measure is investigated, using probabilistic and analytic
potential theoretical methods. We establish a Feynman-Kac formula associated with measures charging no polar set and belonging
to an extended Kato class. A main tool of this approach is the validity of a Khas’minskii Lemma for Stieltjes exponentials
of positive left continuous additive functionals.
相似文献
82.
83.
Sanja Damjanovic 《Progress in Particle and Nuclear Physics》2009,62(2):486-491
Clear signs of excess dileptons above the known sources have been found at the SPS for a long time. However, a real clarification of these observations was only recently achieved by NA60, measuring dimuons with unprecedented precision in 158A GeV In-In collisions. The excess mass spectrum in the region is consistent with a dominant contribution from π+π−→ρ→μ+μ− annihilation. The associated ρ spectral function shows a strong broadening, but essentially no shift in mass. In the region , the excess is found to be prompt, not due to enhanced charm production. The inverse slope parameter associated with the transverse momentum spectra rises with mass up to the ρ, followed by a sudden decline above. While the initial rise, coupled to a hierarchy in hadron freeze-out, points to radial flow of a hadronic decay source, the decline above signals a transition to a low-flow source, presumably of partonic origin. The mass spectra show a steep rise towards low masses characteristic of Planck-like radiation. The polarization of the excess referred to the Collins Soper frame is found to be isotropic. All observations are consistent with a global interpretation of the excess as thermal radiation. We conclude with a short discussion of a possible link to direct photons. 相似文献
84.
A. A. Nikiforov E. A. Maslov N. K. Skripnikova O. G. Volokitin 《Thermophysics and Aeromechanics》2009,16(1):149-153
Herein the fundamentally new unit for production of silicate refractory melts with the use of high-concentrated heat fluxes
is considered. Mathematical model describing temperature fields in skull layer in the process of the plasma flow interaction
with the particles of refractory silicate material has been developed. Typical numerical results of temperature distribution
in various sections of the skull layer are presented. Numerical and experimental data have been compared, and their fair agreement
is obtained.
The work was financially supported by RF President (Grant No. MK 1110.2008.8). 相似文献
85.
86.
87.
应用多光子非线性Compton散射模型和有限时域差分法,对Compton散射对磁化等离子体光子晶体缺陷模密温特性的影响进行了理论分析和数值模拟。结果表明,与Compton散射前的情况相比,Compton散射使低温低频处光子禁带中存在缺陷模的明显度降低,缺陷模频率增大,缺陷模和透射率峰值减小;使高温高频处缺陷模和透射率峰值、缺陷模频率显著增大,禁带宽减小,缺陷模位置向高频方向移动。随着电子密度的增大,散射减小了禁带增大效应和缺陷模减小效应,增强了缺陷模频率增大效应;随着电子密度的降低,散射增强了禁带变窄效应、缺陷模峰值增大效应和缺陷模频率减小效应。利用Compton散射,可实现对缺陷模密温特性的有效控制。 相似文献
88.
The results of spectroscopic investigation of plane plasma discharge and sputtering processes in the triode system are presented. The forced electric discharge with currents of 1–4 A at an argon pressure of 1 mTorr was studied using the emission spectroscopy method. The spectra of plasma discharge were observed in the 200–1100 nm wavelength range. Two metal targets, gold and silver, were used for sputtering. It was found that a part of sputtered particles is ionized in plasma. The emission spectra of the ionized gold and silver species were observed as a function of target voltage while sputtering. It was shown that the number of ionized metal species depends on the energy of argon ions. 相似文献
89.
给出了寂静放电产生的非平衡态氧等离子体特性的实验研究结果,并对空气中及氧气中合成臭氧的特性进行了研究,得到了在纯氧放电时臭氧质量浓度C= 18.9m g ·L- 1、臭氧产率Q=1800m g ·h- 1、臭氧单能产率η= 70g ·(kW ·h)- 1 的实验结果,同时对影响C、Q的因素也进行了研究。最后,就臭氧对造纸黑液的脱色、降粘及脱木素的作用进行了实验探讨 相似文献
90.
A new method of online concentration capillary electrochromatography using a lauryl methacrylate-based monolithic column was developed for determination of three β(2)-agonists including salbutamol, procaterol, and formoterol. The separation parameters including acetonitrile concentration, running buffer pH, and concentration were evaluated. To improve the sensitivity, an online concentration method with combination of the chromatographic zone-sharpening effect and field-enhanced sample-stacking effect has been developed in which the concentration parameters including injection voltage, injection time, as well as sample matrix were systematically studied. Under the optimized conditions, baseline separation of three β(2)-agonists was achieved within 4 min. When compared to the conventional sample injection, this online concentration technique increased their corresponding sensitivities up to 45-, 36-, and 320-fold, respectively. Furthermore, good repeatability was obtained with relative standard deviations (RSDs) for migration times within 0.84% and those for peak areas less than 6.35% (n = 5) in the experiment. The proposed method was successfully applied to the determination of above-mentioned β(2)-agonists in urine sample. The recoveries of spiked urine samples were between 82.4% and 109.1% with RSDs less than 9.97%. 相似文献