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11.
G. Ruder 《Isotopes in environmental and health studies》2013,49(1-2):14-16
Seit nahezu 10 Jahren warden vom VEB Robotron Meβelektronik “Otto Schön” Dresden kontinuierliche Füllstandsmeβeinrichtungen hergestellt. Sie arbeiten nach dem Prinzip der Strahlenstreuung im Füllgut. Quelle und Strahlungsdetektor befinden sich — durch einen Absorber getrennt — in einer gemeinsamen Sonde. Die Sonde wird durch einen Motorantrieb dem jeweiligen Füllstand nachgeführt. Diese Messung wird bei Behälterhöhen bis maximal 40 m eingesetzt. In den Behälter ist der Einbau eines Schutzrohres für die Sonde erforderlich. Da strahlungsquelle und Detektor in einer gemeinsamen Sonde untergebracht sind, wird keine groβe Quellenaktivität benötigt. Die beschriebene neue Entwicklung ersetzt ab 2. Halbjahr 1982 den mit einigen Nachteilen behafteten Vorläufer dieser Füllstandsmeβanlage. Durch die vorgenommenen Verbesserungen warden der Inbetriebnahme- und der Wartungsaufwand verringert und die Zuverlässigkeit erhöbt. 相似文献
12.
《Current Applied Physics》2015,15(3):302-306
We propose a method for simultaneously measuring the front and back surface profiles of transparent optical components. The proposed method combines dual wavelength transmission deflectometry with liquids to record distorted phases at different wavelengths, and then numerically reconstructs the three-dimensional phase information to image the front and back surfaces of the lens. We propose a theoretical model to determine the surface information, and the imaging of achromatic lenses is experimentally demonstrated. Unlike conventional transmission deflectometry, our proposed method supports direct observation of the front and back surface profiles of the optical elements. Compared with other techniques such as interferometry, the proposed setup is simpler to align, has lower cost, and does not require coherent illumination. The proposed method can be applied to normal transmission deflectometry for determining the three-dimensional surface profiles of optical components. 相似文献
13.
J. E. Komosiński 《Isotopes in environmental and health studies》2013,49(5):199-201
Studies on the workability of precise seeders by means of labelling methods has been possible due to the solution of the following problems: labelling of seeds, radiation collimation of labelled seeds being sown, elaboration of measuring and registering systems as well as processing systems of a measuring signal. The developed method allows for precise, quick and fully objective evaluation of the studied seeders to be done under natural conditions. 相似文献
14.
Tobias Fieback Frieder DreisbachMarcus Petermann Roland SpanEckard Weidner 《Fluid Phase Equilibria》2011,301(2):217-224
A novel measuring method is presented here that allows sorption and solvation measurements near to different process conditions. Especially for the sorption kinetics it is important that the measuring conditions are similar to later applications. Particularly for high pressure sorption measurements this claim could not be fulfilled for most technical applications.The advantage of the measuring methods presented here is that solid bed samples in high pressure gravimetry can be measured under flow-through conditions in both directions and, for the first time in high pressure gravimetry, liquid samples can be measured under flow-through conditions. Especially for ionic liquids, of which a large variety of new substances with unknown sorption potentials have been synthesised in the last few years, this results in much shorter measuring times.The first measurements presented here show that the new system allows for measuring times around 26 times shorter for an ionic liquid. 相似文献
15.
Determinations of soil moisture witli the aid of neutron moisture meters require calibrations under real conditions. Some efficient methods for calibrating such moisture gauges are described and working examples are presented. 相似文献
16.
We carry out a systematic study of the different contributions to the deviations of the elliptic flows from the quark number scaling in high energy heavy ion collision in a quark combination model.The effects that we considered are:the resonance decay,the flavor dependence of the quark elliptic flow and the combination of quarks/antiquarks with slightly different transverse momenta.Our results show that the deviations observed in experiments can be well reproduced within the combination framework if all the three effects are considered. We make a detailed analysis of the different contributions using a Monte-Carlo program and suggest measuring the quark number scaling in intermediate pT range more precisely. 相似文献
17.
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
18.
本文提出了一种用线阵CCD非接触实时测量塑料导线直径的仪器,它有如下特点:(1)采用了对被测目标所发出的烟雾不敏感的光学系统,提高了测量精度;(2)采用工作于脉冲方式的大功率近红外LED做照明光源,其寿命比采用白炽灯作为光源大为增长,同时缩小了体积并有利于抑制可见光的干扰;(3)对电信号采用了两级滤波、直流恢复、自适应阈值二值化等处理技术;(4)采用定标的方法来消除目标位置移动的影响,提高了测量精度,降低了加工装配精度要求。现场使用证明,它能长期可靠地工作,总的测量误差小于±0.02mm。 相似文献
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