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931.
932.
933.
934.
Oleg I. Belous Anatoliy I. Fisun Anatoliy A. Kirilenko Viktor K. Korneenkov Vladimir S. Miroshnichenko 《International Journal of Infrared and Millimeter Waves》1997,18(2):445-461
Theoretical and experimental results of an investigation into a new resonant system have been obtained. This system is named
the sphere-corner-echelette open resonator (SCEOR) due to the employment of a mirror that was formed by two echelettes at
the angles of 45° to the resonator axis. It turns ont that this resonator is excited on the specific modes not unique to others
oscillating systems.
There are presented the results of the experimental research of the orotron oscillator with the SCEOR. The spectrum of this
device contains only the fundamental modes such as theT E M
006,T E M
007,T E M
008. The efficiency of the orotron is improved, when all other factors are the same the orotron with a much used sphere-cylindrical
open resonator. 相似文献
935.
Mark W. Beach Nelson G. Rondan Bruce B. Gerhart Bill G. Stobby Vladimir M. Shvartsberg 《Polymer Degradation and Stability》2008,93(9):1664-1673
Experimental methods as well as thermodynamic modeling techniques were utilized to explore potential gas and condensed-phase contributions of various flame retardant (FR) additives with polystyrene polymer. FR additives investigated include hexabromocyclododecane (HBCD), triphenyl phosphine oxide (TPPO), triphenyl phosphate (TPP), triphenyl phosphine sulfide (TPPS), and sulfur. Flame studies of fundamental FR activity were also employed using molecular beam mass spectrometry analysis of FR active species directly in a flame system. The flame studies show direct evidence for active bromine (HBr, Br) species for HBCD and active phosphorous species (HPO2, PO, PO2 HPO3) species for TPPO and TPP which provide high potential for gas-phase activity for these FR additives. Various experimental measurements were also done to assess the degradation species and the degree of degradation of polystyrene by the FR additives. These studies support enhanced degradation of the base polystyrene polymer by the FR additive as a major pathway for condensed FR activity for HBCD and sulfur FR additives. Phosphorous based structures appear to show little enhancement of polystyrene degradation. 相似文献
936.
Vladimir L. Kalashnikov 《Central European Journal of Physics》2008,6(1):80-83
The spherically symmetric vacuum metric in the relativistic theory of gravity is analyzed numerically. It is found that there
is no deviation of the numerical solution from that of general relativity except in the near-horizon range. The solution obtained
has the well-established analytical asymptotics for both the near-and far-horizon limits. It satisfies the causality principle
and does not impose a lower limit on the graviton mass.
相似文献
937.
938.
This study investigated the vapor-phase sorption of hydrocarbons (HC) of various chemical nature (n-hexane, iso-octane, benzene, toluene and p-xylene) on zeolite-clay material (ZCM) of Tatarsky-Shatrashansky deposit (Tatarstan, Russia). For comparison, we also studied HC sorption on natural high-grade zeolite (Z) of St. Cloud Mine (New Mexico, USA), two local bentonite clays and synthetic zeolite-molecular sieve Ms5A. As a result, sorption capacity of ZCM towards aliphatic and aromatic HC was significantly higher than the sorption capacity of Z but lower than that of clays. In addition, the data showed that HC sorption on ZCM occurs as surface adsorption. The comparison with Ms5A and erionite ZAPS, a natural Mexican zeolite, revealed that both ZCM and Z do not interact as microporous selective sorbents with linear alkanes. The main differences in HC sorption on ZCM and Z were ZCM higher sorption capacity towards both aliphatic and aromatic HC, as well as its lower sorption sensitivity to the type of HC. We found that the reason for these differences is the presence of large amount of clay minerals in ZCM. To summarize, ZCM can be considered as a suitable adsorbent for protection and remediation of HC-contaminated soils. 相似文献
939.
940.
We investigate the distribution of some global measures of deviation between the empirical distribution function and its least
concave majorant. In the case that the underlying distribution has a strictly decreasing density, we prove asymptotic normality
for several L
k
-type distances. In the case of a uniform distribution, we also establish their limit distribution together with that of the
supremum distance. It turns out that in the uniform case, the measures of deviation are of greater order and their limit distributions
are different. 相似文献