Effects of uncertainty of excitation condition on error of method of fundamental parameters in X-ray fluorescence analysis

The errors of the method of fundamental parameters in X-ray analysis due to deviation of device characteristics (anode voltage, angles of incidence of the primary radiation and the take-off the fluorescence, thickness of anodic coatings of X-ray tubes of the shot type, and purity of the exciting spectrum) from those used in the calculation of the nominal values are considered. It is shown that the contribution of these errors can reach 0.5–1 rel. % for the uncertainties in units of the fundamental parameters that are typical of X-ray equipment and for a significant difference in the composition of the analyzed and standard samples (particularly when “pure metals” and a nonlinear calibration functions are used as reference samples), which is especially important for high-precision determination of the main components.     

Experimental-numerical investigation of the dynamic stability of flexural-torsional vibrations of compressor blades under conditions of attached and separated flow. Part 1. Procedure and equipment for the determination of nonstationary aerodynamic characteristics

We present the results of investigations of the aerodynamic stability of flexural-torsional vibrations of compressor blades under conditions of attached and separated flow with regard for the cross and mutual aerodynamic links of the blades in a broad range of variations of the phase shift, the ratio of the amplitudes of translational and angular components of their displacements, and the angle of attack. A procedure and equipment used for the experimental determination of the nonstationary aerodynamic characteristics of the blades are described on the basis of the model of flat-plate airfoil cascades. __________ Translated from Problemy Prochnosti, No. 2, pp. 129–142, March–April, 2007.     

Equipment for the Spectral Characterization of High-Temperature Particles

The spectral radiant characteristics of plume particles of a solid rocket engine are important in the design of the engine specific impulse, ablative material, and plume flame hiding. These parameters are measured from tests of the engine. Some equipment has been established to realize particle heating, uniform particle distribution, and measurements based on an FTIR spectral instrument. The equipment is based on SiC heating and is divided into a warm-up chamber and a measurement chamber to improve the particle temperature stability. A special design of uniform particle distribution combined with an acoustic levitation device is used to determine the particle falling speed. The spectral characteristics and the transmission rate of the particles have been measured by using the system including a standard blackbody, an assembled optical system, and an FTIR spectrometer. The measurements of particle concentration and temperature are given in detail. The instrument specifications are as follows: temperature range – 60–1500 °C; spectral range – 0.60–25 μm; and particle dimension range – 10–500 μm. Paper presented at the Seventh International Workshop on Subsecond Thermophysics, October 6–8, 2004, Orléans, France.     

Corrosion and stress-corrosion resistance of deposited metals in hydrogen-sulfide solutions

We study the corrosion, electrochemical, and corrosion–mechanical properties of deposited KKh30N6VSR cobalt-based, NKh15SR3 nickel-based, and Kh16N8S5 iron-based alloys in a standard NACE hydrogen-sulfide solution. It is shown that the deposited Kh16N8S5 iron-based alloy is unsuitable for these conditions due to its low corrosion resistance and susceptibility to hydrogen-induced cracking. The cobalt- and nickel-based alloys are suitable for the surfacing of the components of shutoff fittings of the oil-and-gas extraction equipment. However, as far as the “operating characteristics–cost” ratio is concerned, the nickel-based alloy outweighs the cobalt- based alloy.     

Modeling of solar-radiation transfer in the spherical system of atmosphere-earth’s surface

The study gives a characteristic of the developed model of solar-radiation transfer in the spherical system atmosphere-earth’s surface. Account is taken of the vertical profiles of the aerosol and gas components of the atmosphere, the anisotropy of the reflection of the earth’s mantle, the properties of the relief of the earth’s surface, the characteristics of the wind wave, and the optical properties of the aqueous medium. The problem of radiation transfer is considered in the approximation of the small-angle modification of the method of spherical harmonics. The polar and azimuthal distributions of the components of the Stokes vector are obtained. The integral radiation characteristics and the temperature and rate of heating of the medium at various levels are determined within the framework of a general calculation scheme.     

Use of electro-rheological fluids in a damping device

This paper presents results of experimental studies of an electro-rheological shock absorber based on a controlled hydrosuspension designed to damp a wheeled tractor driver’s cab accommodating not only the operator but also complex electronic equipment by regulating the rheological characteristics of the working fluid by means of an external electric field. The characteristics and dependences of the operating conditions of the electro-rheological shock absorber are presented. The dissipative processes have been estimated. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 78, No. 5, pp. 101–108, September–October, 2005.     

A method of determining the instrumental component of the error of high-precision equipment for measuring complex reflection coefficient

A method of constructing an adequate model of the instrumental component of the uneliminated systematic error of high-precision equipment for measuring complex reflection coefficient is considered, which enables the contradiction between the effort involved in realizing the model employed and the error in estimating the metrological characteristics of the equipment to be resolved. __________ Translated from Izmeritel’naya Tekhnika, No. 10, pp. 64–67, October, 2006.     

Instrument-shielding in measurements of characteristics of electromagnetic compatibility

A refined expression is obtained for the shielding efficiency required for detectors used in “free-field” measurements of characteristics of the minority emissions of transmitting radio-communications equipment. Translated from Izmeritel'naya Tekhnika, No. 4, pp. 53–55, April, 1997.     

Monochromatic radiation source for calibration of the relative spectral sensitivity of earth observation instruments

The design of the major components and parts of a wide-aperture monochromatic radiation source for calibration of earth observation instruments, and its technical and metrological characteristics, are discussed. The uncertainty budget for reproducing the relative spectral distribution of the source at wavelengths of 0.3–2.5 μm is calculated.     

Laser methods and facilities for monitoring the geometric dimensions of components

Comparative characteristics are provided for laser methods of measuring geometric dimensions of components. The main problems are considered that arise with measurement by the triangulation method. An instrument is described that makes it possible to measure the parameters of railway wagon spring suspenders. __________ Translated from Izmeritel’naya Tekhnika, No. 2. pp. 32–35, February, 2008.     

A fatigue-test apparatus for hollow shafts subject to combined torsion,bending, and axial forces

A system is described for fatigue tests on large-scale and heavily loaded components of shaft type subject to joint loading by torsional and bending moments together with axial forces. The performance of the test equipment is described and the mechanical characteristics are given. Translated from Problemy Prochnosti, No. 9, pp. 92–94, September, 1993.     

Equivalent electrical method of determining the amplitude-frequency characteristics of eddy-current vibratory displacement sensors

An equivalent method and equipment for determining the amplitude-frequency characteristics of eddy-current vibratory displacement sensors are considered. Translated from Izmeritel'naya Tekhnika, No. 6, pp. 43–45, June, 2000.     

Experimental equipment for evaluation of the strength characteristics of ceramics materials

We describe the design and operating characteristics of a complex of experimental equipment developed at the Special Design and Technological Office of the Institute of Problems of Strength of the National Academy of Sciences of Ukraine for determination of the characteristics of strength, elasticity, and crack resistance of ceramics and other brittle nonmetallic materials and investigation of fracture processes in these materials within the temperature range of 20–1450°C. The equipment developed enables one to decrease the measurement errors significantly and increase both the efficiency of the tests and the amount of accumulated data. Institute of Problems of Strength, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Problemy Prochnosti, No. 5, pp. 117–126, September–October, 1999.     

Ensuring uniformity of measurements in microwave radiometry

Standard instruments for measuring brightness temperature, developed at the All-Russia Research Institute of Physicotechnical and Radio Measurements during the last 10–15 years, are considered. It is shown that, using these instruments and equipment of the highest accuracy for measuring the parameters of highly directional antennas in the microwave band, one can produce State Standards with metrological characteristics which satisfy modern requirements. Translated from Izmeritel’naya Tekhnika, No. 1, pp. 51–56, January, 2009.     

Universal digital measuring system

A universal measuring instrument is proposed for investigating the quasi-dc and dynamic current-voltage characteristics of two-terminal networks and the transient amplitude-frequency and phase-frequency characteristics of various types of electronic equipment. Signals can be measured in the voltage range 10 mV to 100 V and the current range 1 mA to 1 A. Signals are generated with voltage amplitudes in the range 10 mV to 10 V and current amplitudes in the range 1 mA to 2 A. The sampling frequency range of input and output signals is 1 kHz to 20 MHz in steps of 1 kHz. The errors in measuring instantaneous values of voltage and current are respectively 2.5% and 3% in the frequency range 0–5 MHz. Translated from Izmeritel'naya Tekhnika, No. 6, pp. 52–54, June, 1998.     

Automatic laser vibration gauge

This paper describes a non-contact laser device for measuring the parameters of vibrations; its technical characteristics and domain of application are discussed. The accuracy achieved in measurements is 0.01 μm for linear displacement, and 0.0001 μm for the amplitude of spectral components of vibrations in the audio-frequency range. Translated from Izmeritel'naya Tekhnika, No. 2, pp. 13–15, February, 1996.     

Analysis of measurement information on steady-state vibrations

Nowadays practically all forms of machine, including aircraft, are saturated with all kinds of electronic equipment. The equipment performs not only a service function but is the “brain” which is responsible for the efficiency of the machine. The present article is devoted, to analyzing information concerning steady-state vibrations. Translated from Izmeritel'naya Tekhnika, No. 8, pp. 22–23, August, 2000.     

Status and prospects of metrological support for laser medicine and laser medical technology

This article examines trends and prospective developments in the metrological support of laser medicine and the design of laser-based medical instruments. The main characteristics of the measurement procedures being developed to calibrate, test, and certify laser medical equipment are presented. Translated from Izmeritel'naya Tekhnika, No. 9, pp. 41–46, September, 1998.     

Multi-scale EFG model for Simulating Concrete Material

In this paper, a new multi-scale numerical model is presented using meshless element free Galerkin (EFG) method to simulate the multi-scale constitutive relation of concrete. The scale separation is based on the decomposition of the mesh free shape function into α and β scales, similar decomposition is also adopted for the constitutive equations. And the constitutive relations in different scales for concrete are established. The multi-scale EFG model is utilized for discretization of components of concrete block, which are aggregate, cement and transition region. The strengths of these components are adopted according to Weibull distribution. Consequently, the multi-scale EFG model is applied to describe the evolutionary processes of damage, the propagation of cracks and the characteristics of hysteresis of concrete. The plain static analysis of concrete block is performed by using this model and the calculated result is discussed.