Modern Instrumentation and Practical Application of Flame Atomic Emission Spectrometry

Received: 31.01.24. Revised: 24.02.24. Accepted: 24.02.24. Available online: 04.03.24.Despite the advent of atomic absorption spectrometry and inductively coupled plasma, FAES as an analytical tool continues to be efficiently used for the determination of alkali and alkaline earth metals: the method is characterized by simplicity and speed of implementation, and its implementation requires simple and inexpensive equipment. The fields of application of the FAES method are very diverse: these are environmental control, food industry, agriculture, geology, medicine, pharmacology, nuclear and bioenergy, metallurgy and the chemical industry.The modern instrumentation for flame atomic emission spectrometry (FAES) is overviewed: the main technical (composition of the fuel gas used, dispersing element, number of analytical channels, reference channel, detecting element, sampling method) and analytical (determined elements, range of determined concentrations, limits and the accuracy of their determination, the duration of a single measurement, the equired amount of the analyzed sample) characteristics of flame photometers for industrial and clinical use as well as spectrophotometers currently made by various manufacturers such as Sherwood Scientific Ltd., BWB Technologies UK Ltd., Labtron Equipment Ltd., Labnics Equipment Ltd. and JENWAY Ltd (UK); A.KRÜSS Optronic (Germany); Cole Parmer Instrument Company and Labfon Equipment Inc. (USA); Inesa Analytical Instrument Co., Ltd (China); OJSC Zagorsk Optical and Mechanical Plant, Unico-SIS LLC and VMK-Optoelectronics LLC (Russia); Manti Lab Solutions, Labtronics, Systonic, Globe Instruments, Electronics India, Lasany (India). The main areas of application of FAES are presented – bioenergy, agriculture (analysis of plants, soil extracts and fertilizers), mineral raw materials (geology), clinical medicine and pharmaceuticals, food industry, environmental control (analysis of drinking, technical and waste water), nuclear energy, metallurgy and chemical industry, as well as some features and problems associated with the preparation of samples for analysis by the FAES method. The review includes references to works on the practical application of FAES, published mainly from 1998 to 2023

СОВРЕМЕННЫЕ АВТОМАТИЧЕСКИЕ CHNS/O/X-АНАЛИЗАТОРЫ ОРГАНИЧЕСКИХ СОЕДИНЕНИЙ

A review of the modern market for the automatic element analyzers widely used to control carbon, hydrogen, nitrogen, sulfur, oxygen and halogens, all of which are the main elements making up the organic compounds content and determining their properties, is presented. The operation principles and device variants of the main blocks of CHNS/O/X analyzers are considered including the sample introduction unit, the reactor unit, the combustion products separation unit and the detection unit. The latest developments of element analyzer manufacturers directed to optimize the individual stages of elemental analysis namely the application of double furnace technology, the incineration in tubes with a high temperature resistant ceramic coating, the application of a flame sensor for monitoring the combustion process, the injection of oxygen under pressure to ensure the efficient combustion of the most complex matrices, the use of separation systems such as already-established classical version of the gas chromatography or the temperature-programming desorption methods as well as the other detection systems are reviewed. The data on the most important technical and analytical characteristics of the analyzers such as Analytik Jena (Germany), Elementar Analysensysteme GmbH (Germany), Thermo Fisher Scientific (USA), PerkinElmer (USA), LECO (USA), EuroVector (Italy), CE Instruments (Italy ), Exeter Analytical (UK) are presented along with the data on the number of injected samples, the number and the design of the reactors, the carrier gases used, the methods of the separation and detection of combustion products, the types and the masses of the samples, the elements and ranges of the determined concentrations, and the duration of the analyses.Keywords: elemental analysis, analyzer, encapsulation, combustion, reactor, detector, calibration(Russian) DOI: http://dx.doi.org/10.15826/analitika.2018.22.1.001E.A. Zauer Volgograd State Technical University,Lenin Avenue, 28, Volgograd, 400005, Russian FederationДан обзор современного рынка автоматических элементных анализаторов, широко применяемых для контроля содержания углерода, водорода, азота, серы, кислорода и галогенов – основных элементов, входящих в состав органических соединений и определяющих их свойства. Рассмотрены принцип действия и варианты устройства основных блоков CHNS/O/Х-анализаторов: блока ввода образцов, реакторного блока, блока разделения продуктов сжигания и блока детектирования. Отмечены последние разработки фирм-производителей элементных анализаторов, направленные на оптимизацию отдельных стадий элементного анализа: применение технологии сдвоенной печи, сжигание в трубках с устойчивым к высоким температурам керамическим покрытием, применение датчика пламени для контроля за процессом сжигания, инжекция кислорода под давлением для обеспечения эффективного сжигания самых сложных матриц, применение систем разделения с использованием уже ставшего классическим варианта газовой хроматографии или метода температурно-программируемой десорбции, применение различных систем детектирования. Представлены данные о наиболее важных технических и аналитических характеристиках анализаторов таких фирм, как Analytik Jena (Германия), Elementar Analysensysteme GmbH (Германия), Thermo Fisher Scientific (США), PerkinElmer (США), LECO (США), EuroVector (Италия), CE Instruments (Италия), Exeter Analytical (Великобритания): число вводимых проб, число и конструкция реактора, используемый газ-носитель, способ разделения и детектирования продуктов сгорания, тип и масса образца, определяемые элементы и диапазоны их концентраций, длительность анализа.Ключевые слова: элементный анализ, анализатор, капсулирование, сжигание, реактор, детектор, калибровкаDOI: http://dx.doi.org/10.15826/analitika.2018.22.1.00

The Politics of Feminism: the Impact of Media Discourse on Reality

Рассмотрен феминистский медиадискурс как новый, устойчивый тренд в русскоязычных СМИ. Выявлено его влияние на российскую действительность.The article considers the feminist media discourse as a new, stable trend in the Russian-language media. Its influence on the Russian reality is revealed

Modern Automatic CHNS/O/X Organic Compound Analyzers

A review of the modern market for the automatic element analyzers widely used to control carbon, hydrogen, nitrogen, sulfur, oxygen and halogens, all of which are the main elements making up the organic compounds content and determining their properties, is presented. The operation principles and device variants of the main blocks of CHNS/O/X analyzers are considered including the sample introduction unit, the reactor unit, the combustion products separation unit and the detection unit. The latest developments of element analyzer manufacturers directed to optimize the individual stages of elemental analysis namely the application of double furnace technology, the incineration in tubes with a high temperature resistant ceramic coating, the application of a flame sensor for monitoring the combustion process, the injection of oxygen under pressure to ensure the efficient combustion of the most complex matrices, the use of separation systems such as already-established classical version of the gas chromatography or the temperature-programming desorption methods as well as the other detection systems are reviewed. The data on the most important technical and analytical characteristics of the analyzers such as Analytik Jena (Germany), Elementar Analysensysteme GmbH (Germany), Thermo Fisher Scientific (USA), PerkinElmer (USA), LECO (USA), EuroVector (Italy), CE Instruments (Italy ), Exeter Analytical (UK) are presented along with the data on the number of injected samples, the number and the design of the reactors, the carrier gases used, the methods of the separation and detection of combustion products, the types and the masses of the samples, the elements and ranges of the determined concentrations, and the duration of the analyses.Дан обзор современного рынка автоматических элементных анализаторов, широко применяемых для контроля содержания углерода, водорода, азота, серы, кислорода и галогенов – основных элементов, входящих в состав органических соединений и определяющих их свойства. Рассмотрены принцип действия и варианты устройства основных блоков CHNS/O/Х-анализаторов: блока ввода образцов, реакторного блока, блока разделения продуктов сжигания и блока детектирования. Отмечены последние разработки фирм-производителей элементных анализаторов, направленные на оптимизацию отдельных стадий элементного анализа: применение технологии сдвоенной печи, сжигание в трубках с устойчивым к высоким температурам керамическим покрытием, применение датчика пламени для контроля за процессом сжигания, инжекция кислорода под давлением для обеспечения эффективного сжигания самых сложных матриц, применение систем разделения с использованием уже ставшего классическим варианта газовой хроматографии или метода температурно-программируемой десорбции, применение различных систем детектирования. Представлены данные о наиболее важных технических и аналитических характеристиках анализаторов таких фирм, как Analytik Jena (Германия), Elementar Analysensysteme GmbH (Германия), Thermo Fisher Scientific (США), PerkinElmer (США), LECO (США), EuroVector (Италия), CE Instruments (Италия), Exeter Analytical (Великобритания): число вводимых проб, число и конструкция реактора, используемый газ-носитель, способ разделения и детектирования продуктов сгорания, тип и масса образца, определяемые элементы и диапазоны их концентраций, длительность анализа

СОВРЕМЕННЫЕ АНАЛИЗАТОРЫ ДЛЯ ОПРЕДЕЛЕНИЯ АЗОТА МЕТОДОМ КЬЕЛЬДАЛЯ

Current review covers all main stages of the quantitative determination of nitrogen by the Kjeldahl method: preparation and acid mineralization of samples, distillation, and various chemical and instrumental options for determining the ammonia released after the treatment of mineralization products with alkali. The review also describes the latest technical solutions used to improve and automate certain stages of analysis such as the usage of block and IR digesters that significantly increases the efficiency of sample mineralization and reduces its duration; the usage of automatic lifts for the mineralized samples, which reduces the work of the operator with the heavy and hot chemical samples as much as possible; the usage of autosampler, which provides the automatic transfer of mineralized samples to the distiller; the automation of distillation and titration processes; the use of software for processing the analysis results. The following technical characteristics of the basic components of automatic analyzers for the nitrogen determination by the Kjeldahl method are systematized: digesters, distillers, and titrators produced by such well-known companies as Buchi (Switzerland), C. Gerhardt, Behr Labor-Technik GmbH and FoodALYT GmbH (Germany), Foss Tecator (Denmark, Sweden), VELP Scientifica (Italy), J.P.Selecta (Spain), Hanon Instruments (China), OOO VPK Sibagropribor and OOO Vilitek (Russia). The data on the characteristics of the analyzers is also provided and includes the number and volume of test tubes (flasks), the time of mineralization, distillation and analysis, mass (volume) of the sample, and the lower limit of nitrogen detection.Keywords: Kjeldahl method, acid mineralization, distillation and quantitative determination of ammonia, automatic nitrogen analyzerDOI: http://dx.doi.org/10.15826/analitika.2019.23.2.002(Russian)E.A. Zauer, A.B. ErshovVolgograd State Technical University, pr. Lenina, 28, Volgograd, 400005,Russian FederationВ предлагаемом обзоре рассмотрены основные стадии определения азота методом Кьельдаля: подготовка и кислотная минерализация проб, отгонка и различные варианты (химические и инструментальные) определения аммиака, выделившегося после обработки продуктов минерализации щелочью. Приведены новые технические решения последних лет по совершенствованию и автоматизации отдельных стадий анализа: применение блочных и ИК-дигесторов, существенно повысивших эффективность минерализации образцов и снизивших ее длительность; использование автоматических подъемников минерализованных проб, максимально сокративших работу оператора с тяжелыми пробами и горячими химическими веществами; автосемплеров, обеспечивающих автоматическую передачу минерализованных проб в дистиллятор; автоматизация процессов дистилляции и титрования; использование программного обеспечения для обработки результатов анализа. Систематизированы технические характеристики основных узлов автоматических анализаторов для определения азота методом Кьельдаля – дигесторов, дистилляторов и титраторов, выпускаемых такими известными фирмами, как Buchi (Швейцария), C. Gerhardt, Behr Labor-Technik GmbH и FoodALYT GmbH (Германия), Foss Tecator (Дания, Швеция), VELP Scientifica (Италия), J.P.Selecta (Испания), Hanon Instruments (Китай), ООО ВПК Сибагроприбор и ООО «Вилитек» (Россия). Также приведены данные об основных аналитических характеристиках анализаторов: числе и объеме пробирок (колб), времени минерализации, дистилляции и анализа; массе (объеме) пробы, нижнем пределе обнаружения азота.Ключевые слова: метод Кьельдаля, кислотная минерализация, отгонка и определение аммиака, автоматический анализатор азотаDOI: http://dx.doi.org/10.15826/analitika.2019.23.2.00

Nonlinear left-handed metamaterials

We analyze nonlinear properties of microstructured materials with negative refraction, the so-called left-handed metamaterials. We demonstrate that the hysteresis-type dependence of the magnetic permeability on the field intensity allows changing the material properties from left- to right-handed and back. Using the finite-difference time-domain simulations, we study wave transmission through the slab of nonlinear left-handed material, and predict existence of temporal solitons in such materials. We demonstrate also that nonlinear left-handed metamaterials can support both TE- and TM-polarized self-trapped localized beams, spatial electromagnetic solitons. Such solitons appear as single- and multi-hump beams, being either symmetric or antisymmetric, and they can exist due to the hysteresis-type magnetic nonlinearity and the effective domains of negative magnetic permeability.Comment: 7 pages, 8 figure

Porosity estimation of Phyllostachys edulis (Moso bamboo) by computed tomography and backscattered electron imaging

This study aims to investigate and quantify the porosity in the cross section of Phyllostachys edulis (Moso bamboo) culm wall. The porosity results are expected to be utilised in numerical study of heat and moisture transfer. Computed tomography (CT) and backscattered electron (BSE) imaging methods are utilised in this study because these two methods allow measurements of the anisotropic features of bamboo specimens. The results of these two methods can be represented as the function of the real dimension rather than the pore size distribution of the specimen. The specimens are obtained from eight different locations along the Moso bamboo culms. Both internodes and nodes specimens are measured in this study. The average porosity, standard deviation (SD) and coefficient of variation (COV) are calculated for BSE and CT results. Pearson product-moment correlation coefficient (PPMCC) is also calculated in this study to analyse the correlation between the BSE results and CT results. Typical porosity results from 400 sampling points and 10 portions average porosity are analysed in this study. The CT scanning results show similar trend with BSE results. The correlation relationship between BSE and CT results approaches moderate correlation level to strong correlation level. The average porosity of internode specimens is from 43.9 to 58.8 % by BSE measurement and from 44.9 to 63.4 % by CT measurement. The average porosity of node specimens is from 37.4 to 56.6 % by BSE measurement and from 32.1 to 62.2 % by CT measurement