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This study examined the measurement conditions of the texture profile analysis (TPA) experiments that are typically used to measure the physical properties of sausage. As the measurement conditions (compression ratio and cross-head speed) were changed, the significant differences between the values of textural parameters (hardness, adhesiveness, springiness, cohesiveness, chewiness) of samples changed. Furthermore, among the measurement conditions, there was more variation in the significant difference between the value of samples due to a change in the compression ratio than due to a change in the cross-head speed. The highest variation in significant difference was observed between the values of cohesiveness of samples due to changes in measurement conditions, whereas the lowest variation in significant difference was observed between the values of springiness of samples due to change in measurement conditions. Therefore, it is desirable to provide a clear basis for setting specific measurement conditions for TPA test, since significant differences in the values of textural parameters of samples were caused by differences in cross-head speed or compression ratio, not by a difference in samples, when analyzing the cohesiveness of sausage, especially.

The effectiveness of the magnetic Barkhausen noise method (MBN), used for non-destructive testing of ferromagnetic materials, depends to a large extent on a number of factors determining the measurement conditions. The use of conditions allowing the highest possible level of discrimination between the various states of the materials state is of highest importance. Therefore, this paper presents an analysis of the impact of measurement conditions on Barkhausen noise signals observed for various states of the material conditions. Taking into consideration the stochastic nature of MBN and the complex characterization of its changes, the analysis was based on the time-frequency representation of the MBN signal. The paper presents selected distributions achieved using two transformation methods. In addi- tion, the extraction methods of features allowing the quantification of complex information were given. Finally, the discrimination ability for a number of parameters and features of MBN signals were deter- mined and the obtained results were discussed.

Natural gas is the main energy resource in our country. Its share in total primary energy supply today is about 30 %. According to the Energy Strategy of Ukraine for the period until 2035 it is planned to remain the share at the same level. The requirements of the normative-technical documents in force in determining the quality indicators of natural gases are analysed. Gas quality is the degree of compliance of natural gas indicators with the established requirements, which is determined by its composition and physical properties. Comparison was made with similar European and Russian standards. Some of these characteristics (such as carbon dioxide content, measurement range, combustion heat values, etc.) contradict each other. A methodology based on the theory of fuzzy logic and linguistic variable is proposed for complex assessment of natural gas quality. Factors characterizing the quantitative and qualitative parameters of the physical and chemical properties of the natural gas extracted, the quality of preparation (purification) of natural gas for transportation, and the technical conditions of operation of gas distribution networks of the settlement have been established. Their formalization and hierarchical classification have been completed. For the factors of influence on the quality of natural gas universal sets are selected in accordance with the requirements of the current normative and technical documents harmonized with the European legislation. The choice of the most important physicochemical properties of natural gas for its energy evaluation is substantiated. The proposed hierarchical classification of factors affecting the quality of natural gas allows us to construct the functions of the estimation of the classified factors using linguistic variables. Belonging functions of the influencing factors on quality of natural gas are the basis for modelling of the expert system for support of management decision-making in the process of assessment and forecasting the natural gas quality, Проаналізовані вимоги чинних в Україні нормативно-технічних документів щодо визначення показників якості природних газів. Виконано порівняння з аналогічними європейськими та російськими стандартами. Для комплексного оцінювання якості природного газу запропоновано методику, що базується на теорії нечіткої логіки та лінгвістичної змінної.Встановлено чинники, що характеризують кількісні та якісні параметри фізико-хімічних властивостей видобутого з родовища природного газу, якість підготовки (очищення) природного газу для транспортування та технічні умови експлуатації газорозподільних мереж населеного пункту. Виконано їхню формалізацію та ієрархічну класифікацію. Для факторів впливу на якість природного газу універсальні множини вибрано відповідно до вимог чинних нормативно-технічних документів, гармонізованих з європейським законодавством. Обґрунтовано вибір найбільш важливих фізико-хімічних властивостей природного газу для його енергетичної оцінки

Variations in elemental abundances in carbonate archives offer a wealth of information that can be used as a proxy for the palaeoenvironment and diagenetic history. The state-of-the-art portable handheld X-ray Fluorescence (pXRF) and laboratory micro X-ray Fluorescence (μXRF) instruments provide a relatively inexpensive, fast and non-destructive way of acquiring these trace element composition data. However, there are well-known issues and limitations regarding the method of spectrum acquisition and the conversion of XRF spectra into quantitative elemental mass fractions. This study offers a guideline for the appropriate use of these XRF techniques for the study of carbonates. Using certified calcium carbonate and dolomite standards, accuracy and reproducibility of a pXRF (Bruker AXS Tracer IV) and a μXRF (Bruker M4 Tornado) device are tested under various measurement conditions. The experimental set-up allowed for the variation of several parameters, including the measurement area, integration time, quantification method and measurement strategy. The effects on the accuracy and reproducibility of the quantified elemental abundance results are examined to assess the optimal performance conditions for both devices for the determination of trace element abundances in natural carbonates. The limits of detection and quantification are evaluated for both instruments for a range of trace elements commonly used as palaeoenvironmental proxies (e.g. Sr, Mn and Fe). The quality of the XRF spectra is evaluated using spectral processing software. As a result, two new methods for the determination of optimized parameter combinations are proposed for a range of commonly used elements. The Time of Stable Reproducibility (TSR) is based on optimizing the measurement reproducibility by examining the change of the relative standard deviation per time unit and proposing an integration time threshold for reproducible measurements. The Time of Stable Accuracy (TSA) is based on optimizing the measurement accuracy by studying changes in accuracy as a function of increasing integration time and defining an integration time threshold for accurate measurements. An overview table including minimum integration times by which a reliable measurement is achieved is provided for all analyzed elements and experimental set-ups for this study. However, the methodological approach that is developed here is applicable to other (carbonate) materials as well. A comparison between the two X-ray fluorescence instruments allows the evaluation of their respective advantages and disadvantages. Finally, we recommend optimal measurement strategies and techniques for specific research questions.

Heat transfer coefficients are often used to describe the thermal behavior of radiant systems in buildings and how they transfer heat between their cooled/heated surfaces and the room. In addition to current standards, several studies have been conducted to determine such heat transfer coefficients by means of experiments and simulations. Inconsistency is evident in the values and expressions derived for this purpose. The present study investigated possible sources of discrepancy in an extensive literature review of articles, standards and guidelines that focus on the heat transfer coefficients of cooled/heated surfaces. Measurement data provided by different authors were analyzed to compare both the amount of heat transfer and the estimated heat transfer coefficients. These estimated values and expressions were used to predict the measured data reported in other articles, to examine their accuracy. Larger deviations and prediction errors were found in the total and convective heat transfer values than in radiant heat transfer, which had a range of errors within ±20% throughout the literature. The major sources of error were shown to be the calculation procedure for each heat transfer mechanism, the choice of reference temperature and its measurement height and position, and room dimensions. It is suggested that heat transfer coefficients should be chosen by matching the calculation/measurement conditions in which they were obtained to the purpose and conditions in which they will be applied.

The present review details the methods used for the measurement of cells and their exudates using atomic force microscopy (AFM) and outlines the general conclusions drawn by the mechanical characterization of biological materials through this method. AFM is a material characterization technique that can be operated in liquid conditions, allowing its use for the investigation of the mechanical properties of biological materials in their native environments. AFM has been used for the mechanical investigation of proteins, nucleic acids, biofilms, secretions, membrane bilayers, tissues and bacterial or eukaryotic cells; however, comparison between studies is difficult due to variances between tip sizes and morphologies, sample fixation and immobilization strategies, conditions of measurement and the mechanical parameters used for the quantification of biomaterial response. Although standard protocols for the AFM investigation of biological materials are limited and minor differences in measurement conditions may create large discrepancies, the method is nonetheless highly effective for comparatively evaluating the mechanical integrity of biomaterials and can be used for the real-time acquisition of elasticity data following the introduction of a chemical or mechanical stimulus. While it is currently of limited diagnostic value, the technique is also useful for basic research in cancer biology and the characterization of disease progression and wound healing processes.

11 European laboratories worked together to study the influence of a lot of parameters of the measurement of light vehicle emission factors on vehicle bench, in order to improve the accuracy, reliability and representativeness of emission factors: driving patterns (driving cycles, gear choice behaviour, driver and cycle following), vehicle related parameters (technical characteristics of the vehicle, emission stability, emission degradation, fuel properties, vehicle cooling and preconditioning), vehicle sampling (method, sample size), and laboratory related parameters (ambient temperature and humidity, dynamometer setting, dilution ratio, heated line sampling temperature, PM filter preconditioning, response time, dilution air). The results are based on literature synthesis, on about 2700 specific tests with 183 vehicles and on the reprocessing of more than 900 tests. These tests concern the regulated atmospheric pollutants and pre-Euro to Euro 4 vehicles. We did not find any influence of 7 parameters, and find only a qualitative influence for 7 other parameters. 6 parameters have a clear and quantifiable influence and 5 among them allow us to design correction factors to normalise emission measurements: gearshift strategy, vehicle mileage, ambient temperature and humidity, dilution ratio. The sixth influencing parameter is the driving cycle, sometimes more significant than the fuel or the emission standard. Finally the European driving behaviour can be reduced to 15 reference test patterns. The results allow us to design recommendations or guidelines for the emission factor measurement method. A set of 3 real-world driving cycles, the so-called Artemis cycles, is designed to be representative of the European driving behaviour. 3 emission models are designed, accurate at best for any driving behaviour: one based on the instantaneous speed (after an emission signal inverse modelling), one according to the distribution of the instantaneous speed and acceleration, and a third according to seven dynamic related parameters.

Ten European laboratories worked together to study the influence of a lot of parameters of the measurement of light vehicle emission factors on vehicle bench, in order to improve the accuracy, reliability and representativeness of emission factors: driving patterns (driving cycles, gear choice behaviour, driver and cycle following), vehicle related parameters (technical characteristics of the vehicle, emission stability, emission degradation, fuel properties, vehicle cooling and preconditioning), vehicle sampling (method, sample size), and laboratory related parameters (ambient temperature and humidity, dynamometer setting, dilution ratio, heated line sampling temperature, PM filter preconditioning, response time, dilution air). The results are based on literature synthesis, on about 2700 specific tests with 183 vehicles and on the reprocessing of more than 900 tests. These tests concern the regulated atmospheric pollutants and pre-Euro to Euro 4 vehicles. We did not find any influence of 7 parameters, and find only a qualitative influence for 7 other parameters. 6 parameters have a clear and quantifiable influence and 5 among them allow us to design correction factors to normalise emission measurements: gearshift strategy, vehicle mileage, ambient temperature and humidity, dilution ratio. The sixth influencing parameter is the driving cycle, sometimes more significant than the fuel or the emission standard. The results allow us to design recommendations or guidelines for the emission factor measurement method.

International audience; Phase transformations of [001], [110], and [111] oriented Pb(Zn 1/3Nb2/3)O3-6%PbTiO3 (PZN-6%PT) single crystals have been investigated by means of dielectric permittivity and loss, x-ray diffraction and depolarization current as function of temperature (from 250 to 500 K). The unpoled samples undergo R-T-C phase transition sequence during zero field heating (ZFH), where R, T, and C are rhombohedral, tetragonal, and cubic phases, respectively. Under electric field (0.5 kV/cm), an intermediate orthorhombic (O) phase is induced between the T and R phases in the field cooling (FC) process. This phase reappears during subsequent zero field heating of the poled sample (zero field heating after field cooling ZFHaFC). The existence range of this O phase depends on both the crystal orientation and the measurement conditions (FC or ZFHaFC). Finally, for the [001] direction, it was found that the piezoelectric activity of the intermediate phase is the highest. © 2013 AIP Publishing LLC.