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No. 1

Kawate E.:

Comparison of Reflection Methods for Determining Optical Constants with STAR GEM

Abstract:  A new optical accessory was developed which can measure both the absolute reflectance and transmittance as the incident angle is continuously varied in the wide range from 0.5⁰ to 89.5⁰. Incident angle dependences of reflectance were measured for S- and P-polarizations of an aluminum mirror. Optical constants and their accuracy were determined.

Keywords: Optical constants, absolute reflectance, accuracy

Ondracek F., Salavcova L., Mika M., Spirkova J., Ctyroky J.:

Characterization of Erbium Doped Glass Optical Waveguides by a Fine Tunable Semiconductor Laser

Abstract:  In this paper we describe some methods for characterization of the new active optical channel waveguides (suitable for waveguide lasers and amplifiers at 1550 nm) by means of a fine-tunable semiconductor laser. The channel waveguides were fabricated by ion-exchange technique  K+ <->  Na+  and  Ag+ < -> Na+  in the newly designed Er-doped silicate glass substrate. The effect of the used technology on the basic parameters of the waveguide, i.e. optical field distribution, spectral dependencies of absorption and optical losses, was investigated. In the conclusion, the results obtained are discussed mainly from the point of view of differences in the waveguides’ fabrication technology, and new trend in the fabrication is suggested.

Keywords: Erbium doped glass, channel waveguides, optical losses, absorption

Hain M., Bartl J., Jacko V.:

The Use of Infrared Radiation in Measurement and Non-destructive Testing

Abstract:  Infrared radiation is used in a passive or active way in several types of measuring and testing methods. Advantage of these methods is contactless measurement, usually very fast and without any destructive influence on tested/measured objects. In the contribution several infrared methods and their applications are described, among them infrared thermometry for contactless temperature measurement, infrared thermography for temperature fields measurement and visualisation and at last near infrared reflectography for non-destructive testing of works of art.

Keywords:  Measurement, testing, contactless, temperature, near infrared, reflectography

Rabiega J.:

Practical Realisation of 0 ^oC Temperature Standard

Abstract:  The main purpose of the paper there was to build, check and test behaviour of 0 ^oC temperature standard. The stand has to be simple, cheap and easy to build. Described bellow stand provides accuracy of ± 0,01 ^oC and works impeccable in our chair since several years.

Keywords:   Temperature standard, realisation, testing

No. 2

Van Driessche I., Schoofs B., Penneman G., Bruneel E., Hoste S.:

Review of the Application of High Temperature Superconductors in Coated Conductor Development and the Measurement of their Properties

Abstract:  Since the 1960s, Nb-Ti, exhibiting a superconducting transition temperature Tc of 9K, and Nb₃Sn, with a Tc of 18K has been the materials of choice for superconducting applications. The prospects for the future changed dramatically with the discovery of ceramic high temperature superconductors exhibiting Tc values well above the boiling temperature of liquid nitrogen (77K). These materials are now widely considered for large power applications, electronics and magnets including a.o. power transmission cables, motors, generators, fault current limiters, transformers, NMR and MRI. The fabrication of useful conductors out of these layered cuprates encountered some problems in areas such as chemical and structural purity, stability, oxygen stoichiometry and weak links. However, a first generation of silver sheathed composites based on Bi₂-_xPb_xSr₂Ca₂Cu₃O₁₀ has already been commercialised. It is now a widespread view that superconducting wires with high performance under strong magnetic fields and at elevated temperatures above liquid nitrogen, will need to be realised using the (RE)Ba₂Cu₃O_y materials. Because of the weak link nature of these materials, a second generation of biaxially aligned coated conductors was developed. As a consequence, many deposition techniques have been studied to grow thin films of the superconducting (RE)Ba₂Cu₃O_y and adequate buffer layers on suitably prepared textured substrates. In this paper, the critical parameters in the deposition of thin films using vacuum and non-vacuum techniques will be reviewed. Finally, this review will address the measurement of the obtained properties of these coated conductors. The most important practical characteristic of a superconductor is its critical current density. Spectroscopic methods such as I.R. play an important role in the development of adequate precursors for chemical solution deposition of thin films. Finally, micro structural analysis using XRD, SEM and TEM is important to reveal the relation of these features on the transport properties of the films.

Keywords:  Superconductors, transition temperature, critical parameters

De Buysser K., Herman G. G., Bruneel E., Hoste S., Van Driessche I.:

Determination of the Number of Unpaired Electrons in Metal-complexes. A Comparison Between the Evans’Method and Susceptometer Results

Abstract:  1,4,8,11-tetraazacyclotetradecane (cyclam) is widely known as an ideal ligand for chelating heavy metal ions such as Ni²⁺ and Cu²⁺ in aqueous media. In this work the consequences of chelation on the preference for high spin or low spin configuration were investigated for Fe³⁺, Ni²⁺, Cu²⁺ and Cr³⁺. Two methods were used to determine the number of unpaired electrons in the solid and dissolved complex. First the change of magnetic susceptibility of the crystalline powder as a function of temperature was measured. In the second case Evans NMR-based method was used to obtain information about the number of unpaired electrons in the dissolved complexes. In some cases, such as Fe³⁺ and Ni²⁺, a discrepancy between the two methods was noticed. This behaviour is discussed in terms of the preference of the large high spin Ni²⁺-ion to switch to the smaller low spin Ni²⁺-ion in the aqueous environment, which better fits the cavity of the ligand in the square planar geometry. The results are influenced by the geometry of the complex, the aggregation state and the dimensions of the ions.

Keywords:  NMR method, 1,4,8,11 – tetraazacyclotetradecane, high spin, low spin

Nieciag H., Chuchro Z.:

The Analytical Solution of the Problems in Pipes Measurements with IOS Coordinate Measuring Machines

Abstract:  The paper presents the analytical solution of determination of coordinate reference system for pipes system measurements. The transformation matrix is a composition of the consecutive calculated submatrices, basing on the chosen three points from frame of pipes.

Keywords:  Pipes, measurements, transformation, matrices

Chugunov Yu V., Fiala V.:

Measurement of Wave Electric Field in Space Plasmas: the Antenna Effective Length at Resonance

Abstract:  We show that the effective length of a dipole antenna grows by more than an order of magnitude close to the plasma resonance in a streaming solar wind. This finding is to be used in interpretation of wave electric field measurements in space plasmas.

Keywords:  Double sphere dipole, effective length, resonance conditions

No. 3

Tapajna M., Harmatha L., Husekova K., Frohlich K.:

Measurement of Generation Parameters on Ru/HfO₂/Si MOS Capacitor

Abstract:  We report extended analysis for measurement of generation lifetime and surface generation velocity, s_g, on advanced gate stack with high-κ dielectric using leakage current characteristics in inversion condition. Proposed technique was examined on Ru/HfO₂/Si MOS capacitor annealed in forming gas (90% N₂ + 10% H₂) at temperatures 430 and 510 °C. It was found that s_g decreases with FGA temperature increasing, however, density of interface traps, D_it, unexpectedly increases after second FGA. The results are discussed together with capacitance vs. gate voltage measurement.

Keywords:  Capacitor, MOS, inverse conditions, measurement of lifetime

Sebok M., Simko M., Chupac M.:

Infrared Measurement of Temperature and Spectral Filters Application

Abstract:  We are engaged in temperature and heat measuring problems as well as infrared radiation in our contribution. It is inevitable to be familiar with these problems at the contemporary usage of thermovision system.

Keywords:   Temperature measurement, spectral filters, thermovision

Jayanthy T., Sankaranarayanan P. E .:

Measurement of Dry Rubber Content in Latex Using Microwave Technique

Abstract:  This paper deals with an experimental study on the dielectric properties of natural rubber as a function of dry rubber content. The cost of rubber is directly dependant on the dry rubber content and therefore the study gains its importance. It shows that the dielectric properties of Hevea latex are mainly due to the orientation of loosely bound water molecules .The experiment was done at room temperature using a dielectric liquid cell used to hold the sample of natural rubber under study. The study comes to the inference that there is an inversely proportional relationship between the dry rubber content and its dielectric constant.  i.e. as the moisture content increases, the dielectric constant also increases.

Keywords:  Dielectric constant, latex, dry rubber

Odon A.:

Voltage Response of Pyroelectric PVDF Detector to Pulse Source of Optical Radiation

Abstract:  Voltage response of a designed and constructed pyroelectric PVDF detector to pulse radiation was experimentally investigated. The detector performance has been tested and its time parameters, response linearity as a function of energy and width of optical pulses, frequency response and temperature characteristics were determined.

Keywords:   Pyroelectric detector, PVDF sensor, pyroelectric polymer

No. 4

Ondraskova A., Sevcik S., Rosenberg L., Kostecky P., Turna L., Kohut I.:

The Detection of Magnetic Field Component of Schumann Eigenmodes Using Search Coil Sensors at Modra Observatory

Abstract:  At Modra observatory, more than three years of the regular monitoring of electric field component of Schumann eigenmodes have been performed. Attempts to detect their magnetic field component have been made by means of big search coils. In this article, we describe the experimental equipment and principal results obtained.

Keywords:   Magnetic field, search coils, Schumann resonances, spectral analysis

Jankauskas Z., Kvedaras V., Zaveckas V.:

Measurement of the Bandwidth of Helicon Maser

Abstract:  Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid - state plasmas of metals and semiconductors when a strong magnetic field is applied. In Helicon Maser (HM) the helicons are exited by RFs much higher than the helicon generation frequency. The higher frequency e/m field may be called a pumping field. In analogy with the usual maser (or laser) the magnetized semiconductor sample plays the role of active material and the connecting cable – the role of high quality external resonator. The bandwidth of HM is much narrower than in case of isolated sample (the same situation as in case of laser). The new method of HM bandwidth measurement is considered. InSb and Ge were used for active materials. The constant magnetic field varied within the interval 0 – 23 Tesla.

Keywords:  Helicon maser, magnetoplasmic waves, microwave resonator

Gros P., Kurekova E.:

Advanced Experiments Design for the Three-Torch Plasma Cutter Testing

Abstract:  Nowadays exist many applications of CNC plasma cutting machines. They are focuses namely for preparation of products for following technological procedures (welding in most cases). A brand new advanced Triple Torch Plasma Rotating Unit has been developed in cooperation of the Faculty of Mechanical Eng., STU in Bratislava and Microstep-Group. The phase of technological tests requires determination of the repeated positioning accuracy of the developed unit. Therefore number of experiments must be performed. The presented paper introduces modified experiments design with significantly decreased number of measurements.

Keywords:  Experiments design, plasma bevel cutting, triple torch unit, positioning accuracy

Mikulczyński T.:

Pressure measurement in disintegrated medium

Abstract:  Application of a piezoelectric sensor for pressure measurement in disintegrated medium is presented. It was evidenced that the sensor must be equipped with a liquid adaptor to enable non-directional pressure measurement in disintegrated medium. Results of dynamic examination of the developed sensor are presented. It was found that the developed liquid adaptor is an inertialess element. Results of pressure measurements in dynamic densened moulding sand using the developed sensor are also presented.

Keywords: disintegrated medium, unit pressure, piezoelectric sensor, liquid adaptor, measurement

No. 5

Grman J., Ravas R., Syrova L.:

Contribution to Localization Algorithm in the Defectoscopy of Steam Generator Tubes by Eddy-currents

Abstract:  Fast localization of defects and structure elements in the defectoscopy of steam generator tubes is the field where application of wavelet transformation is very perspective. Primary task is to find positions of potential indications within signal and secondary task is to calculate optimal boundaries of indications with respect to their future use in process of classification. Paper presents modification to already presented localization algorithm based on method of wavelet transformation.

Keywords:  Localization, wavelets, eddy-currents, steam generator

Bielik R., Hallon J.:

Program System for Controlling EMC Measurements and Collecting Measured Data

Abstract:  The aim of this submission is to introduce a wide program system assigned to control EMC measurement. This device was developed on the Department of Measurement and can be divided into three modules. First component realizes defined supply voltage fails. The core of listed module is the programmable generator. The next component presents remote client for collecting, math processing and measured data evaluation from various EMC measurements. It works thought a serial interface and offers an option to simultaneous watch the three different channels for data collecting and one for parameters sending. A client for collecting, displaying and evaluation of received data constitutes the last component. The intention of this client is a measurement of higher harmonic frequencies. Additional optional functions of this module are the application of norm defined filtering and comparing measured data with norm defined limit values.

Keywords:  EMC, harmonic analysis, measurement software, GPIB

Kopcansky P., Koneracka M., Timko M., Potocova I., Jurikova A., Tomasovicova N.:

The Hydrodynamic Size of Magnetic Carrier Systems Determined by Means of Forced Rayleigh Scattering Experiment

Abstract:  A new method for the determination of size distribution of magnetic carrier systems and for the proof of successful immobilization of biomolecules to magnetic particles was developed. The method is based on Forced Rayleigh Scattering (FRS) experiment, in which a diffraction concentration grating is created in a thin sample of colloidal fluid due to the periodic spatial temperature modulation.

Keywords:   Forced Rayleigh Scattering, magnetic fluid, thermo diffusion, size distribution

86-93

Hesse O., Pankratyev S.:

Usage of Magnetic Field Sensors for Low Frequency Eddy Current Testing

Abstract:  In the past there were several attempts to use highly sophisticated magnetic field sensors like SQUID and Fluxgate sensors for sensitive low frequency eddy current (EC) testing to detect deep buried defects in metal parts. Although very good results could be achieved such testing systems can hardly be used in real industrial applications because of the complexity and costs of such systems and their insufficient robustness.

Keywords:  Current testing, GMR sensors, AMR sensors, inductive coils

No. 6

94-97

Smalins E., Gross U., Jansons J., Ubelis A.:

Atomic Spectra from RF Electrodeless Discharge Sources for UV and VUV Spectrometry and Analytical Measurements

Abstract:  Electrodeless discharge lamps (EDLs) have been demonstrated to be an intense source of halogen atomic emissions in the ultraviolet (UV) and far UV (VUV) spectral region. Previously developed iodine resonance spectra source has been demonstrated as an intensive source of Iodine resonance lines. Iodine EDL has been successfully adopted in flash photolysis experiment. Quantitative measurements of concentration kinetics of iodine atomic species in an I₂+O₃ system are possible. There are evidences that bromine sources could be used in similar way. A newly designed and developed bromine resonance source with high quality quartz window giving 163.36nm resonance line proves that bromine EDLs can be used in analytical spectroscopy. Further improvements in technology are necessary to increase the intensity of obtained 163.36 nm resonance line and to retrieve other resonance lines like 157.65 nm and 153.19 nm.

Key words:  Atomic Spectra, Electrodeless discharge lamps (EDL), Flash photolysis (FP)

98-103

V. Boháč, Ľ. Kubičár, V.Vretenár

Methodology of the testing of model for contact pulse transient method and influence of the disturbance effects on evaluating thermophysical parameters of the PMMA

Abstract: The transient methods for the testing of thermophysical properties of materials are suitable for the material characterization, regarding the stability of the structure or structure changes invoked by treatment after production within technology process. Contact pulse transient technique is sensitive enough to be able to record the change in material structure during any kind of material treatment that influences overall material property.

The reliability of any method in practice depends on fact how much does fit the model with experimental conditions. A detailed study has to be performed to find experimental circumstances when disturbing effects influence experimental data.

In this paper we discuss the methodology of mathematical tests of physical model for pulse transient method. Additional tests were found for the case of real experiment when disturbance effects like heat loss from the specimen surface and non-ideality of the heat source influence the ideal model.

Keywords: pulse transient method, thermal diffusivity, thermal conductivity, specific heat, model testing

104 - 114

S. Yadav, V.K. Gupta, O. Prakash, A. K. Bandyopadhyay

Evaluation of Associated Uncertainties in Calibration of Direct Pressure Indicating Electromechanical Devices

Abstract:  A wide range of direct pressure measuring electromechanical transducers is now commercially available in the market. In such electromechanical type direct indicating devices, the applied pressure is directly measured by a sensing element with a suitable mechanism into an analog / digital electrical signal in terms of voltage, current or frequency. The generation of such signals is based upon some electromechanical effects viz. inductive, capacitive, resistive, piezoelectric, piezoresistive, reluctive, resonative and optoelectric etc.  A wide range of such pressure measuring instruments is now commercially available in the market. The high-pressure technology and new applications demand that the best instrumentation should ensure the lowest measurement uncertainty, particularly in the fluid media. The calculation of the calibration results and associated uncertainties is a complex matter involving many influencing quantities. The present paper describes a novel method for evaluating uncertainty in pressure measurement using electromechanical type direct pressure indicating devices through statistical analysis of errors. The method of evaluation of associated uncertainties is in line with ISO and EA Guidelines on the evaluation and expression of uncertainty in measurement. The results thus obtained are compared with the results obtained by using standard technique described in EA guidelines. Both the methods are quite comparable.

Keywords: electromechanical transducers, pressure measurement, uncertainties