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991.
992.
We describe several electrochemical methods used to investigate the possibility of cold fusion phenomena in palladium and titanium tritide cathodes. We performed long-term (up to 77 days) electrolysis experiments with electrochemical cells of the University of Utah type at current densities as high as 1 A/cm2, while monitoring neutron and tritium levels. With some cells, we pulsed the current to determine if neutron bursts would result. In another cell, we used titanium tritide as the cathode to determine if D-T reactions yielding neutrons would occur. In no instance were levels of neutrons or tritium significantly above background except in the titanium tritide cell where isotopic exchange, occcurring between the electrode and the electrolyte, resulted in significant tritium levels. We also combined x-ray photoelectron spectroscopy (XPS) and electrochemical hydrogen permeation experiments to determine the effectiveness of various Pd surface treatment procedures on the resultant electrochemical hydrogen absorption efficiency. Electroanalytical and thermal desorption/gas analysis techniques indicated the maximum loading of H in Pd was to a ratio of HPd=0.8.  相似文献   
993.
994.
Programming and Computer Software - This paper is devoted to event detection as part of news stream analysis. An event is regarded as a group of news texts dedicated to one real-world fact or...  相似文献   
995.
Programming and Computer Software - In the biomedical domain, diagrammatical models have been extensively used to describe and understand the behaviour of biological organisms (biological agents)...  相似文献   
996.
Programming and Computer Software - In 2020 the outbreak of Covid-19 influenced lives of billions of people all around the globe and motivated governments of different countries to revisit the...  相似文献   
997.
The Journal of Supercomputing - In this paper, we propose a parallel source separation system designed to extract heart and lung sounds from single-channel mixtures. The proposed system is based on...  相似文献   
998.
1.  The use of the results of on-site investigations of an irregular wave load on slopes of structures makes it possible to increase the reliability of designing structures.
2.  A differentiated consideration of the wave load according to probability in storms represented by corresponding quasi-steady wave systems can substantially reduce the cost of construction and installation works on objects of various classes and technical purposes.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 24–27, December, 1989.  相似文献   
999.
Stress-sensitivity mapping for surface acoustic waves on quartz   总被引:1,自引:0,他引:1  
A model is presented, relating the velocity shifts of surface acoustic waves (SAW) to the six tensor components of quasistatic stresses. Stress sensitivity is then defined through six independent coefficients, whatever the origin of the stress (direct external forces, thermoelastic stresses) might be. These coefficients, depending on crystal anisotropy, are computed for different cut angles and propagation directions of quartz crystal, and represented as a contour-line mapping. The determination of SAW quartz cuts compensated for both planar isotropic stresses and first-order temperature effects make it possible to define a family of quartz cuts with potentially low stress and temperature sensitivities for oscillator applications.  相似文献   
1000.
It is shown that in natural sciences, interdependences between variables are determined regardless of the distributions of variable values, whereas in science studies, distributions should be used as a starting point. This difference is due the nature of measuring instruments: in natural sciences, measurements are performed with the use of devices, while science of science uses human devices adapting themselves to the measured objects. Practical inferences are drawn.  相似文献   
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