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991.
992.
An example of an opto-pneumatic detector's (OPD) frequency transfer function is presented for the development of an opto-pneumatic interface. The theoretical model is tested through experiments in the laboratory on a real OPD prototype. In this way many of the model's parameters are studied and evaluated, such as the dimensions of the gas chamber, the thickness of the absorbent body, and the load of the OPD. The results obtained are good and show the utility of the studies described here. 相似文献
993.
We have investigated the deformation of a rectangular plate half-embedded in an elastic base and subjected to a mechanical load. Using the apparatus of generalized functions, the problem is reduced to a system of singular integral equations which is solved by the boundary element method. We present the results in the form of isolines of the components of the displacement vector.Translated from Problemy Prochnosti, No. 3, pp. 72–77, March, 1996. 相似文献
994.
V. I. Smirnov 《Measurement Techniques》1996,39(6):636-644
A four-beam two-component laser Doppler anemometer (LDA) with a two-dimensional Raman-Nath ultrasonic cell and a spectral-type
integral adaptive signal processor has been developed for measuring the components of the mean flow velocity, turbulence energy,
and turbulent shear in a gas stratification wind tunnel. The operation of the system and the data reduction are controlled
by running custom-made software on an IBM PC with a CAMAC interface.
Translated from Izmeritel'naya Tekhnika, No. 6, pp. 40–46, June, 1996. 相似文献
995.
M. Balata L. Cadonati M. Laubenstein G. Heusser M. G. Giammarchi R. Scardaoni V. Torri G. Cecchet A. de Bari A. Perotti 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,370(2-3):605-608
The Borexino experiment, for the study of solar neutrino physics, requires radiopurity at the level of 5 × 10−16 g/g 238U equivalent (or 6 × 10−9 Bq/kg) on a detector mass of many tons of scintillator. Feasibility studies are performed in a counting test facility now operating at LNGS, which consists of 4 t of liquid scintillator viewed by 100 photomultipliers and shielded by 100 t of water. The accomplishment of this goal requires the shielding liquid, water, to be at the 10−13 g/g contamination level (1.2 × 10−6 Bq/kg) or better. This paper describes the water purification system; it consists of a combination of several purification processes to remove particulate, radioactive ions, dissolved gases and other impurities. Residual contaminations are measured by analytical or direct-counting techniques. For radon measurement, particularly challenging at this low activity levels, a low background counting method has been developed. 相似文献
996.
Variable-ratio and computational methods are described for improving the accuracy of autotransformer and transformer ac bridges
that take into account and eliminate the additive and multiplicative components of the systematic error due to connecting
leads and jumpers of the measuring circuit.
Translated from Izmeritel'naya Tekhnika, No. 6, pp. 61–63, June, 1996. 相似文献
997.
998.
High-T
c
Bi(Pb)-Sr-Ca-Cu-O thin films have been made on single-crystal MgO substrates using high-pressure dc sputtering technique. X-ray studies confirm the crystallinity and highly oriented structure withc-axis perpendicular to the substrate. By optimizing the annealing schedule the formation of the high-T
c
phase is stabilized. The best film exhibited superconducting transition temperature with zero-resistance temperature,T
c(0), as high as 101 K. Temperature dependence ofJ
c
indicates the presence of Josephson-type weak links. 相似文献
999.
1000.