The present state and current problems of ensuring uniformity of measurements of the parameters of electromagnetic pulses

Information on how to construct and improve the State Special Standard of the units of pulsed electric and magnetic field strengths are presented. The need and possibility of extending the time range of the standard in order to ensure uniformity of measurements of the parameters of very short pulses of electromagnetic fields having a pulse length of down to 10^-10 sec are considered.Translated from Izmeritelnaya Tekhnika, No. 10, pp. 33–35, October, 2004.     

Some metrological problems of analytical measurements

Methods for certifying verification facilities and the metrological characteristics of analytical instruments are considered. Translated from Izmeritel’naya Tekhnika, No. 1, pp. 62–67, January, 2009.     

The structural-energy state of metal nanopowders and the problems of certifying them

The basic characteristics of metal nanopowders, namely, the shape, particle sizes, the metal component content, the chemical activity parameters, the electrochemical characteristics, and the thermodynamic state of the nanoparticles and nanopowders, are considered. Experimental results are presented on the use of standard methods of analysis and the features of their use when determining the above characteristics. It is shown that, for certifying nanopowders as metastable systems, a whole range of methods of analysis is required.     

The present state and future prospects of the development of measurements of electrical quantities

The present state of measurements of electrical quantities is reviewed based on the papers read at the élektroizmereniya-2007 conference. __________ Translated from Izmeritel’naya Tekhnika, No. 11, pp. 35–39, November, 2007.     

Ultrasonic and laser measurements in structural contact problems

This paper deals with two experimental techniques recently set up by the authors which enable the study of contact problems between elastic bodies. The more widely used experimental techniques for determining the response of elastic bodies in unilateral contact include moiré fringes, holography and photoelasticity. The experimental techniques proposed here utilize either the ultrasonic pulse transit time method or the laser beam intensity method. Both techniques are applied to measure the relative displacements and the contact area of beam and plate models in unilateral contact with an elastic half-space model. The experimental results, compared with those obtained by numerical analysis, show the efficiency and validity of the measurement techniques proposed.

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Resume Cet article traite de deux techniques expérimentales récemment mises au point par les auteurs, qui permettent d’étudier les problèmes de contact entre corps élastiques. Les techniques expérimentales les plus largement utilisées pour déterminer la réponse des corps élastiques dans le contact unilatéral sont la méthode du moiré, l’holographie et la photoélasticité. On propose ici deux méthodes expérimentales: l’une par la mesure du temps de réflexion ultrasonique, l’autre par la mesure de l’intensité d’un rayon laser. On applique les deux techniques à la mesure des déplacements relatifs et de la surface de contact entre des modèles de poutre et de plaque en contact unilatéral avec un modèle de semi-espace élastique. Les résultats experimentaux, quand on les compare avec ceux obtenus par analyse numérique, montrent l’efficacité et la validité des techniques de mesure proposées.

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The state of strain in single GaN nanocolumns as derived from micro-photoluminescence measurements

In the present paper, studies on the state of strain in single and ensembles of nanocolumns investigated by photoluminescence spectroscopy will be presented. The GaN nanocolumns were either grown in a bottom-up approach or prepared in a top-down approach by etching compact GaN layers grown on Si(111) and sapphire (0001) substrates. Experimental evidence for strain relaxation of the nanocolumns was found. The difference and development of the strain value for different nanocolumns could be verified by spatially resolved micro-photoluminescence on single nanocolumns separated from their substrate. A common D0X spectral position at 3.473 eV was found for all separated single GaN nanocolumns independent of the substrate or processing technique used, as expected for a relaxed system.     

Present state and future prospects of metrological support for dielectric measurements

The paper discusses the established system of metrological support of dielectric measurements in Russia and in several industrial countries with a developed market economy, the principal characteristics of similar Russian and foreign standard facilities for dielectric measurements and the approach to metrological support of such measurements in national metrological institutes of Russia, Great Britain, Germany, and the USA.Translated from Izmeritel'naya Tekhnika, No. 12, pp. 34–40, December, 1994.