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511.
By the method of electrolytical etching track etching rates Vt and corresponding transversal track etching rates Vtrans of single heavy ion tracks in thin Makrofol KG foils have been measured at ion energies from 10–480 MeV/u. Makrofol KG foils of 8 μm thickness were irradiated perpendicular to the surface with 79Au and 54Xe ions at specific energies with energy loss values of REL=(10–90) *103 MeVcm2/g at GSI Darmstadt, Germany, and Lawrence Berkeley Lab., Cal., USA. Using the electrolytical etching method by measuring the resistance of the foil during the etching process (etching conditions: 6n NaOH, room temperature and controlled 50° C) the breakthrough time and track etching rates Vt, Vtrans and Vm (bulk etching rate) were analysed. Response curves (Vt/Vm)-1 as a function of Restricted Energy Loss (REL), the maximum extension of the ion induced damage perpendicular to the ion path and the dimension of the ion track core depending on the deposited energy can be estimated. 相似文献
512.
J. P. Y. Ho C. W. Y. Yip V. S. Y. Koo D. Nikezic K. N. Yu 《Radiation measurements》2002,35(6):571-573
Equations for calculating track parameters have been proposed, which invariably involve the track etch rate Vt and the bulk etch rate Vb. The present study measured Vb for the LR115 solid-state nuclear track detector using atomic force microscopy (AFM). The detectors were partially masked using rubber cement and then etched in 2.5 N NaOH solution at 60°C for time periods ranging from 5 to 40 min. The rubber cement was then peeled off and cross-sectional images of the LR115 detectors were obtained by AFM. Vb has been found to have different values below and beyond the etching time of about 13.5 min, with the values of 0.0555 and 0.0875 μm min−1, respectively. The increase in Vb with the etching time can be explained by a diffusion-etch model, in which the additional damage of the detector material is due to those etchant ions diffused into the detector over time. Now that Vb has been determined, this can be combined with the track etch rate Vt to calculate track parameters. 相似文献
513.
P. J. Meoli G. H. Olivera G. Saint-Martin O. A. Bernaola P. D. Fainstein R. D. Rivarola 《Radiation measurements》1997,28(1-6):25-26
The track radius calculation reported by Tombrello was applied to experimental data of tracks from several ions and energies in Makrofol E. Qualitative analysis of ion tracks in this material is discussed. These data were also compared with values calculated using the Continuum Distorted Wave-Eikonal Initial State approximation 相似文献
514.
515.
I. E. Qureshi S. Manzoor M. I. Shahzad M. A. Farooq H. A. Khan M. S. Zafar 《Radiation measurements》1995,25(1-4):247-250
The dielectric track detectors are very efficient in registering the main fragments of a heavy ion reaction in the presence of lightly ionizing products and γ-radiations because of their threshold nature of registration and wide-angle acceptance. The binary events, revealed after chemical etching of these detectors, appear as the events having two correlated prongs in the body of the detector. The measurements of the geometrical parameters of these prongs provide the necessary data for subsequent kinematical analysis. We have made a thorough analysis of the two-pronged events in order to understand the physical mechanism of their production, using the track data from the reactions, 相似文献
516.
517.
W. Birkholz P. Yu. Apel M. Danziger F. H u ler M. Hempel A. I. Kuklin S. G. Stetsenko H. Baumbach 《Radiation measurements》1995,25(1-4):57-62
In the past five years were carried out SANS (Small-Angle Neutron Scattering measurements in the JINR to investigate latent and short etched tracks in SSNTD. The results demonstrate the suitability of the method to study not etched and short etched tracks to analyse the etching process, e.g. for nuclear track filter production. The results are in good agreement with other methods as conductivity measurements. 相似文献
518.
A high sensitive (10−4 ppm) fission track detection technique for determination of uranium in liquids was developed. The technique was applied for the measurement of uranium concentration in extraction phosphoric acid and phosphorus fertilizer, viz., ammophous. 相似文献
519.
N. L. Grigorov M. A. Kondratyeva M. I. Panasyuk Ch. A. Tretyakova S. P. Tretyakova D. A. Zhuravlev 《Radiation measurements》1995,25(1-4):331-332
A few exposures of CN-85 detectors on Earth-orbiting satellites in the period 1993–1994 show evidence for the reappearance of the radiation belt from geomagnetically trapped anomalous cosmic ray ions. 相似文献
520.
利用滑块带动金属杆切割亥姆霍兹线圈中心区域匀强磁场的磁感应线,可以产生感应电动势.通过实验可以验证感应电动势大小与金属杆运动速度、长度以及磁感应强度之间的关系,也可以验证感应电动势大小和磁通量变化率成正比. 相似文献