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Objectives. This study described the 4-circle goniometer Syntex P1N and its possible applications in X-ray and neutron structure analysis of single crystals.Methods. The 4-circle goniometer Syntex P1N, due to its high-precision mechanical characteristics and individual components from domestic equipment (sets of DRON type X-ray diffractometers), formed the basis for developing an instrument complex for X-ray and neutron-structure studies.Results. The neutron diffractometer was upgraded based on the Syntex P1N goniometer. Therefore, the 10BF3-based end neutron counter, included in the diffractometer kit, was replaced by the 3He-based domestic side counter, SNM-16. Such a significant reduction in the linear dimensions of the detector allowed us to expand the range of measured angles of 2θ from 90° to 140° and increase the accuracy of the measured interplanar distances accordingly. The goniometer was adjusted relative to the primary neutron beam by placing it on a specially designed plate. Highly accurate measured parameters of the unit cell and the intensity of the reflexes were achieved by optimizing the installation geometry and the protection of the goniometer and detector. Based on the Syntex P1N goniometer, an instrument complex for X-ray diffraction studies has also been developed. Both the developed X-ray and the upgraded neutronography facilities were used to perform experiments to measure the unit cell parameters, the coordinates of atoms, and the parameters of their thermal vibrations on several crystals of domestic synthetic samples: diamond C, silicon Si, halite, or rock salt NaCl, and corundum α-Al2O3. An excellent correlation was achieved by comparing the data obtained with the corresponding chemical crystals’ parameters and reference samples recommended by the International Union of Crystallographers.Conclusions. This paper described a neutron installation and a Syntex P1N neutron diffractometer for the study of single crystals. Based on the latter, an instrument complex for X-ray diffraction studies has also been developed. Experiments on standard samples have shown a high level of accuracy in measuring the lattice parameters, the coordinates of atoms, and the parameters of their thermal vibrations on both the X-ray and neutron diffractometers.

In this paper, the application of zone smelting to remove the trace heavy metal lead from waste acrylonitrile-butadiene-styrene (wABS) plastics was investigated. ABS standard samples with uniform and stable lead content were prepared by the method of lead stearate coupling agent. The structure, thermal stability, morphology and lead content of the standard ABS samples before and after zone smelting were characterized by FTIR, DSC, SEM and ICP-AES. The results showed that the lead content in the front and middle sections of the ABS sample decreased obviously after zone smelting, while the lead content in the tail increased significantly, and the structure, thermal stability and morphology remained basically unchanged. [ABSTRACT FROM AUTHOR]

Measurements of the magnetic moment of a ship are necessary for monitoring safety from magnetic mines and from stealth, by the magnetic field. A modification of the method of measuring the magnetic moment of a ship by using a three-component differential magnetometer is examined. With the aid of computer modeling, a comparison was done of the errors of the method developed by the authors with those of known analogs, and its advantage in precision (by practically one order of magnitude) was established. It is shown that the proposed method can be applied also to magnetic models of ships and standard samples of magnetic materials in order to determine the components of hysteresis loops by magnetization. [ABSTRACT FROM AUTHOR]

BACKGROUND Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is a frequent instrument for the analysis of trace element content. When LA-ICP-MS is used to analyze the element content of minerals, the laser energy density will affect the denudation rate of the sample and thus affect the signal intensity during the analysis. OBJECTIVES To further clarify the impact of laser energy density changes on the quality of test data and the response of different natural minerals to laser energy density. METHODS The element content data of standard samples and nature minerals with different Mohs hardness under different laser energy densities were determined using LA-ICP-MS. Then authors analyzed the relative error (RE) between the test data and the reference values of the standard samples, average of the relative error of elements with RE within the limits of -20%-10% in the same standard sample, and the relative standard deviation of the standard samples and nature minerals test results to evaluate the effect of laser energy density on the test results. RESULTS The minimum laser energy density required to stabilize ablated quartz and fluorite was 4-5J/cm2, which was lower than the previously reported value (10J/cm2), whereas stable denudation of other minerals such as talc, apatite, and corundum require the minimum energy density of generally 1-2J/cm2. Under the different condition of laser energy density, the relative error of most trace elements in standard samples between analytical results and recommended values was less than 20% and the relative standard deviation was less than 10%. The relative standard deviation of most trace element test data was less than 20% for natural minerals with most element contents >1μg/g. Within a certain range, the greater the laser energy density, the smaller the average relative error of the data, and the better the overall quality. CONCLUSIONS Quartz and fluorite require higher laser energy density for stable ablation than other minerals. Within the appropriate range, laser energy density has little effect on the quality of the individual element data, but it affects the overall quality of the data.

This review addresses the history of the creation of standard samples (SS) around the world and in Russia, along with studies of the current condition of the state system for standardization of medicinal products (MP) based on the use of SS. Standardization in the area of drugs is directed to guaranteeing the quality of the items standardized, which includes products (raw materials, other materials, ready MP, etc.), services, and processes. The continuing development of manufacturing technologies and the discovery of novel MP increases the need for standard samples, as drug quality control involves the use of complex, highly effective, specific, and precise physicochemical and biological analysis methods. [ABSTRACT FROM AUTHOR]

BACKGROUND: Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is a frequent instrument for the analysis of trace element content. When LA-ICP-MS is used to analyze the element content of minerals, the laser energy density will affect the denudation rate of the sample and thus affect the signal intensity during the analysis. OBJECTIVES:To further clarify the impact of laser energy density changes on the quality of test data and the response of different natural minerals to laser energy density. METHODS:The element content data of standard samples and nature minerals with different Mohs hardness under different laser energy densities were determined using LA-ICP-MS. Then authors analyzed the relative error (RE) between the test data and the reference values of the standard samples, average of the relative error of elements with RE within the limits of -20%-10% in the same standard sample, and the relative standard deviation of the standard samples and nature minerals test results to evaluate the effect of laser energy density on the test results. RESULTS:The minimum laser energy density required to stabilize ablated quartz and fluorite was 5J/cm2, which was lower than the previously reported value (10J/cm2), whereas stable denudation of other minerals such as talc, apatite, and corundum require the minimum energy density of generally 1-2J/cm2. Under the different condition of laser energy density, the relative error of most trace elements in standard samples between analytical results and recommended values was less than 20% and the relative standard deviation was less than 10%. The relative standard deviation of most trace element test data was less than 20% for natural minerals with most element contents >1μg/g. Within a certain range, the greater the laser energy density, the smaller the average relative error of the data, and the better the overall quality. CONCLUSIONS: Quartz and fluorite require higher laser energy density for stable ablation than other minerals. Within the appropriate range, laser energy density has little effect on the quality of the individual element data, but it affects the overall quality of the data. [ABSTRACT FROM AUTHOR]

Exhaled breath analysis for early disease detection may provide a convenient method for painless and non-invasive diagnosis. In this work, a novel, compact and easy-to-use breath analyzer platform with a modular sensing chamber and direct breath sampling unit is presented. The developed analyzer system comprises a compact, low volume, temperature-controlled sensing chamber in three modules that can host any type of resistive gas sensor arrays. Furthermore, in this study three modular breath analyzers are explicitly tested for reproducibility in a real-life breath analysis experiment with several calibration transfer (CT) techniques using transfer samples from the experiment. The experiment consists of classifying breath samples from 15 subjects before and after eating a specific meal using three instruments. We investigate the possibility to transfer calibration models across instruments using transfer samples from the experiment under study, since representative samples of human breath at some conditions are difficult to simulate in a laboratory. For example, exhaled breath from subjects suffering from a disease for which the biomarkers are mostly unknown. Results show that many transfer samples of all the classes under study (in our case meal/no meal) are needed, although some CT methods present reasonably good results with only one class.

Researches by methods of analytical microscopy and the x-ray analysis have allowed to develop a set of standard samples of composition and structure of the strengthening nanostructured and nanolayer coatings for control of the strengthening nanostructured and nanolayer coatings based on nitrides of the metals used to protect critical parts of the compressor of the gas turbine engine from dust erosion, corrosion and oxidation.

Summary of the research results obtained during the development of the technology of metrological certification and production of standard samples necessary for calibration of the means of diagnostics of aircraft GTE products of wear oils.

Currently, standard samples with high hydrogen concentrations that meet the requirements of hydrogen extraction in an inert atmosphere are not currently available on the market. This article describes the preparation of Ti-H standard samples and the calibration of RHEN602, a hydrogen analyzer, using LECO (LECO, Saint Joseph, MI, USA). Samples of technically pure titanium alloy were chosen as the material for sample production. The creation procedure includes five main steps: sample preparation (polishing to an average roughness of 0.04 μm using sandpaper), annealing, hydrogenation, maintenance in an inert gas atmosphere, and characterization of the samples. The absolute hydrogen concentration in the samples was determined by two methods: volumetric and mass change after the introduction of hydrogen. Furthermore, in-situ X-ray diffraction, temperature programmed desorption (TPD) analysis, and thermogravimetric analysis were used during measurements to investigate the phase transitions in the samples. As a result of this work, a series of calibration samples were prepared in a concentration range up to 4 wt % hydrogen, optimal parameters for measuring high concentrations of hydrogen. The calibration line was obtained and the calibration error was 10%. [ABSTRACT FROM AUTHOR]

The deficiencies of existing standard iron and nickel samples for calibration by means of X-ray diffraction are noted. These standards cannot be used in calibration by magnetic noise recording. A new calibration method based on X-ray diffraction is proposed, using plane samples of the material employed in the manufacture of the actual structures. Theoretical analysis provides the basis for the development of null standards in which a plane sample is deformed by pure flexure or in a cantilever-beam configuration. [ABSTRACT FROM AUTHOR]

Currently, standard samples with high hydrogen concentrations that meet the requirements of hydrogen extraction in an inert atmosphere are not currently available on the market. This article describes the preparation of Ti-H standard samples and the calibration of RHEN602, a hydrogen analyzer, using LECO (LECO, Saint Joseph, MI, USA). Samples of technically pure titanium alloy were chosen as the material for sample production. The creation procedure includes five main steps: sample preparation (polishing to an average roughness of 0.04 μm using sandpaper), annealing, hydrogenation, maintenance in an inert gas atmosphere, and characterization of the samples. The absolute hydrogen concentration in the samples was determined by two methods: volumetric and mass change after the introduction of hydrogen. Furthermore, in-situ X-ray diffraction, temperature programmed desorption (TPD) analysis, and thermogravimetric analysis were used during measurements to investigate the phase transitions in the samples. As a result of this work, a series of calibration samples were prepared in a concentration range up to 4 wt % hydrogen, optimal parameters for measuring high concentrations of hydrogen. The calibration line was obtained and the calibration error was 10%.

Currently, standard samples of hydrogen-metal systems meeting the requirements of glow discharge optical emission spectrometers (GD-OES) are not available on the market. This article describes the preparation of Zr-Nb-H standard samples and the calibration of GD-OES with the usage of these samples. Samples of Zr-2.5Nb were chosen as the material for sample production. The creation procedure includes five main steps: sample preparation (polishing to an average roughness, Ra, of 0.04 m using sandpaper), annealing, hydrogenation, maintenance in an inert gas atmosphere, and characterization of the samples. The absolute hydrogen concentration in the samples was determined volumetrically and calculated from the weight change. The distribution of hydrogen was studied using GD-OES Profiler 2 by Jobin Yvon Emission Horiba Group. As a result of this work, calibration curves of Zr, H, Nb, O, and other elements were obtained. The calibration errors were in the range of 1–5%.

Work at the laboratory for optical-spectral instrumentation at VNIIOFI during 2009-2014 is discussed. The capabilities of dynamic light scattering and atomic-absorption spectroscopy for determining the geometric parameters and concentration of nanoparticles in liquid media have been extended. New means and methods for measurements in biological fluids (blood and plasma) have been developed. A new approach to the creation of standard samples based on nanoparticles has been proposed in order to support the uniformity of fl uorometric measurements. [ABSTRACT FROM AUTHOR]

We consider the architecture of expert systems in software-hardware measuring complexes for oncological (cancer) diagnosis with the use of procedures of image recognition and on the basis of one of the most important methods of oncomorphology - the histological method. We develop a knowledge model and a model (theoretical foundations) for carrying out expert measurements. The adequacy of the models is confirmed by the high efficiency of introduction of the complexes developed into clinical practice. [ABSTRACT FROM AUTHOR]

Abstract: Total reflection X-ray fluorescence (TXRF) and grazing emission X-ray fluorescence (GEXRF) are surface sensitive techniques and can be used for detailed surface studies of different materials, including ultra-low concentration contamination or the lateral and depth distributions of elements. The calibration procedure typically used involves placing a micro-droplet of the standard solution onto a silicon wafer (or quartz backing). After evaporation of the solvent, the residual amount of elements is used as a reference standard. Knowledge of the distribution of residue material on the substrate surface is crucial for precise quantification. In the present work the investigation of the lateral distribution of elements in the multielemental calibrating samples, containing the 23 most commonly studied elements, by using the synchrotron radiation based micro X-ray fluorescence is presented. The goal of this project was the study of a uniformity of the elemental distributions and determination of the residual elements morphology depending on the temperature of the drying process. The X-ray images were compared with optical and SEM images. Paper presents in details the experimental setup, sample preparation procedures, measurements and results. In the analysis of the X-ray images of the sample dried in high temperature the censoring approach was applied improving the quality of statistical analysis. The information on the elements distribution in the calibrating samples can be useful for developing more accurate calibration procedures applied in quantitative analysis of surface sensitive TXRF and GEXRF techniques. [Copyright &y& Elsevier]

The creation of multicomponent reference samples of mass fractions of moisture and protein in grain and grain products, certified values of which are traceable to state standards, is considered. The metrological characteristics of the samples are found at the level of typical world analogs. [ABSTRACT FROM AUTHOR]

This is an analysis of the state of and prospects for metrological support in the area of measuring the surface density of coatings based on the state primary special standard GET 168-2010. The basic characteristics of the standard and its components are discussed. The verification procedure based on this standard and regulated by the standards document GOST R 8.612-2005 is described. The role of standard samples of coating surface density and their place in the testing, verification, and calibration of devices for measuring the thickness of coatings and comparisons with the standard is pointed out in order to confirm its measurement and calibration capabilities. [ABSTRACT FROM AUTHOR]

Results from the development of State Primary Standard GET 176-2010 based on the method of coulometric titration are presented. The physical principles of the method, composition, metrological characteristics, and results of international comparisons of the new standard are considered. [ABSTRACT FROM AUTHOR]

n algorithm of certification of plutonium dioxide by the coulometric method is described. The results of measuring the mass fraction of Pu in PuO, obtained in certifying and confirming measurements in the course of the development of the state standard sample, are given. The mean mass fraction of Pu in the standard sample material and the uncertainty of the certified value are determined. Based on the results obtained and metrological expertise of the documentation in accordance with GOST (State Standard) 8.315-97, the type of plutonium dioxide composition, SS Pl-tot, is approved, included into the state register, and accepted for use in the Russian Federation. [ABSTRACT FROM AUTHOR]

A sample of garnet-biotite plagiogneiss, GBPg-1 is currently being developed as a certified reference material at the Vinogradov Institute of Geochemistry. It was used as the sample that was distributed round 7 of International Proficiency Testing Program (GeoPT7) and was analyzed by 76 geoanalytical laboratories around the world. Twenty Russian laboratories involved in the interlaboratory experiment also analyzed GBPg-1. The resultant analytical data obtained from these two experiments has allowed GBPg-1 to be certified as a state standard sample for 50 elements. It also enabled a comparison of the quality of data developed by the Russian and international geoanalytical laboratories, to optimize the outcome of this interlaboratory experiment. [Copyright &y& Elsevier]

Exhaled breath analysis for early disease detection may provide a convenient method for painless and non-invasive diagnosis. In this work, a novel, compact and easy-to-use breath analyzer platform with a modular sensing chamber and direct breath sampling unit is presented. The developed analyzer system comprises a compact, low volume, temperature-controlled sensing chamber in three modules that can host any type of resistive gas sensor arrays. Furthermore, in this study three modular breath analyzers are explicitly tested for reproducibility in a real-life breath analysis experiment with several calibration transfer (CT) techniques using transfer samples from the experiment. The experiment consists of classifying breath samples from 15 subjects before and after eating a specific meal using three instruments. We investigate the possibility to transfer calibration models across instruments using transfer samples from the experiment under study, since representative samples of human breath at some conditions are difficult to simulate in a laboratory. For example, exhaled breath from subjects suffering from a disease for which the biomarkers are mostly unknown. Results show that many transfer samples of all the classes under study (in our case meal/no meal) are needed, although some CT methods present reasonably good results with only one class. [ABSTRACT FROM AUTHOR]

The paper covers the main principles of setting up and the function of the Russian system of metrological assurance of analytical measurements for the production of light alloys and superalloys. [ABSTRACT FROM AUTHOR]

The current state of production, certification and use of standard samples of aluminium- and titanium-based alloys with specified contents of gas impurities is described. A list of the certified standard samples with a specified gas impurity content which are available in Russia is presented. [ABSTRACT FROM AUTHOR]

Currently, standard samples of hydrogen-metal systems meeting the requirements of glow discharge optical emission spectrometers (GD-OES) are not available on the market. This article describes the preparation of Zr-Nb-H standard samples and the calibration of GD-OES with the usage of these samples. Samples of Zr-2.5Nb were chosen as the material for sample production. The creation procedure includes five main steps: sample preparation (polishing to an average roughness, Ra, of 0.04 m using sandpaper), annealing, hydrogenation, maintenance in an inert gas atmosphere, and characterization of the samples. The absolute hydrogen concentration in the samples was determined volumetrically and calculated from the weight change. The distribution of hydrogen was studied using GD-OES Profiler 2 by Jobin Yvon Emission Horiba Group. As a result of this work, calibration curves of Zr, H, Nb, O, and other elements were obtained. The calibration errors were in the range of 1–5%. [ABSTRACT FROM AUTHOR]