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101.
对60AGeV^16O诱发乳胶核反应靶核碎片多重数分布及其关联进行了实验研究,并与FRITOF1.7加级联机制模型和DIUNUC2.0模型计算结果进行了比较/。 相似文献
102.
T. Tsuruta 《Radiation measurements》2001,34(1-6):167-170
Diallyl phthalate (DAP) resin plates were irradiated with fission fragments, and then etched in a conventional aqueous solution of KOH or a PEW solution containing ethanol, water and KOH. Etched tracks were observed and counted by using an optical microscope. The PEW solution made the fission tracks etch-pits clearer in an incomparably shorter etching time. The large and round etch-pits developed on a smooth surface were convenient for optical automatic counting. These etching characteristics of DAP in a PEW solution are suitable for quantitative analysis of fissionable materials and neutron dosimetry. 相似文献
103.
N. Yasuda K. Uchikawa K. Amemiya N. Watanabe H. Takahashi M. Nakazawa M. Yamamoto K. Ogura 《Radiation measurements》2001,34(1-6):45-49
As a frame work of the study for the latent track size measurement using atomic force microscope, we have measured the minute etch pits and the extremely small amount of bulk etch of CR-39 at the beginning of chemical etching, and obtained its growth curves in nanometer dimensions. The pieces of CR-39 were exposed to 6 MeV/nC and Fe ions with normal incidence angle and were etched in 70°C 7 N NaOH solution for 0.5,1,2,3,5 min. The diameters of latent track were estimated to be 17 nm for Fe ions and 8 nm for C ions, respectively. These values are comparable to the experimental data on the average ‘track core diameters’ that have been obtained by various experimental techniques. 相似文献
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108.
Fission-track registration characteristics of Lexan solid state nuclear track detectors have been used to measure the fast neutron induced fission cross section of232Th. The fast neutrons (?14.2MeV) were produced with the help of an AN-400 model Van-de-Graaff accelerator at Banaras Hindu University laboratory using3H(2H,n)4He reaction and were used to irradiate the fissile target deposited on the plastic detector. The track densityT, registered on the plastic detector is related to the fission cross sectionσ f, through the relationT=knσ føt wheren is the number of fissile atoms per cm2 in the deposit, ø is the neutron flux,k is fission track registration efficiency andt is the time of irradiation. The fission cross sectionσ f of232Th, relative to the well measured fission cross section of238U, was found to be 0.36±0.04 barn. 相似文献
109.
The effect of heat treatment on the latent tracks in cellulose nitrate plastic track detectors has been studied. The bulk
etch rate increases with annealing temperature while the track diameters of different ions in cellulose nitrate decrease with
increase in annealing time and temperature. Experimental results show that for heavier ions higher temperatures are needed
for their complete erasure. The track length and track etch rate are decreased by the application of heat. Experiments reveal
that annealing reduces track density. The vertical tracks are more stable than the oblique tracks and require higher temperature
for their complete erasure. 相似文献
110.
O. S. Maslakova 《Algebra and Logic》2003,42(4):237-265
It is proved that the fixed point group of an arbitrary automorphism of a free group of finite rank has an algorithmically computable basis. 相似文献