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121.
LIU Yan-Ping CHEN Zhao-Yang BA Wei-Zhen FAN Yan-Wei DU Yan-Zhao PAN Shi-Lie GUO Qi 《中国物理C(英文版)》2008,32(5)
The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity.Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-acoess and hazardous.In addition.optical fiber dosimeters are immune to electrical and radio-frequency interference.In this paper,a novel remote optical fiber radiation dosimeter is described.The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL.The measuring range of the dosimeter is from 0.1 to 100 Gy.The equipment is relatively simple and small in size,and has low power consumption.This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions. 相似文献
122.
A continuous surface wetting transition, pinned to a solid-liquid-liquid-vapor tetra coexistence point, is studied by x-ray reflectivity in liquid Ga-Bi binary alloys. The short-range surface potential is determined from the measured temperature evolution of the wetting film. The thermal fluctuations are shown to be insufficient to induce a noticeable breakdown of mean-field behavior, expected in short-range-interacting systems due to their d(u) = 3 upper critical dimensionality. 相似文献
123.
We consider the impact of nonstandard interactions (NSI) of neutrinos on the determination of neutrino mixing parameters at a neutrino factory using nu(-)(e)-->nu(-)(mu) "golden channels" for the measurement of theta(13). We show how a small residual NSI leads to a drastic loss in sensitivity in theta(13), of up to 2 orders of magnitude. This can be somewhat overcome if two baselines are combined. 相似文献
124.
Generation of 740 mW of blue light by intracavity frequency doubling with a first-order quasi-phase-matched KTiOPO(4) crystal 总被引:13,自引:0,他引:13
We report on efficient intracavity frequency doubling of a cw diode-pumped Nd:YAG laser on the (4)F(3/2)?(4)I(9/2) laser transition at 946 nm. The nonlinear crystal used in the experiments was a first-order quasi-phase-matched flux-grown KTiOPO(4) crystal (period, 6.09mum ; thickness, 1 mm; length, 9 mm). The fluctuations in the generated second-harmonic wave were lower than 3% at output powers of as much as 500 mW. The overall optical-to-optical efficiency was 5.7%. A maximum output power of 740 mW of blue light was generated, which was stable for only 0.5 min. The decrease the output power at this power level was attributed to heating and thermal lensing in the periodically poled KTiOPO(4) crystal. The short-term behavior of the second-harmonic wave exhibited switching between a cw mode and chaotic intensity fluctuations. 相似文献
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W. W. Krühler G. Huber H. G. Danielmeyer V. Nekvasil 《Applied Physics A: Materials Science & Processing》1975,8(3):261-268
The pentaphosphate system Nd1?x Y x P5O14 covers four crystalline phases with five different site geometries for Nd. We determined the4F3/2,4I13/2,4I11/2,4I9/2 stark levels and identified the sites spectroscopically, including the case of the monoclinic layer structureC2/c which has two Nd sites. Crystal field calculations for the energy levels in the monoclinic phaseP2 1/c and the orthorhombic phasepnma with tetragonal and orthorhombic site symmetry approximations are reasonable but reveal their shortcomings. As a consequence, we consider it improper to try to calculate rare-earth optical transition probabilities with approximate crystal fields. Random distribution of Nd and Y causes inhomogeneous broadening (~6 Å) which peaks atx=0.5. Thermal equilibrium between the4F3/2 levels is reached within 2–5×10?13 sec. The three room temperature modifications could be lased cw. Pure NdP5O14 was found to be the best laser. 相似文献
128.
Summary Lonazolac and its p-hydroxylated metabolite M1 are determined in serum by high performance liquid chromatography using direct injection of comparatively large volumes with precolumn enrichment. No sample workup is required prior to analysis. Reproducibility, calibration plots, recoveries and detection limits are presented, together with various applications of the method. Data from direct injection of serum are also compared to results from a conventional extraction work-up.Presented at the 14th International Symposium on Chromagraphy London, September, 1982 相似文献
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