A citricultura, introduzida no Brasil na época da colonização e explorada comercialmente a partir dos anos 30 do século passado, é um setor de grande importância para o agronegócio brasileiro. Atualmente, o Brasil detém 50% da produção mundial de laranja e cerca de 85% de toda exportação mundial, representando uma captação de divisas de cerca de 2,5 bilhões de dólares por ano, devido principalmente à exportação do suco de laranja. Apesar do suco ser o principal produto de exportação da citricultura, vários subprodutos com valor comercial são obtidos durante seu processo de produção, tais como os óleos essenciais cítricos. Esses subprodutos localizam-se na casca da fruta e são obtidos durante o processo de extração do suco de laranja por prensagem a frio. Devido ao uso intensivo de pesticidas na citricultura e que muitas vezes se acumula na casca da fruta é comum à obtenção de óleos essenciais com resíduos de pesticidas, o que reduz seu preço de mercado internacional e limita sua inserção em mercados exigentes como o Europeu, Japonês e Americano, por exemplo. Este trabalho propõe o desenvolvimento de metodologias eletroanalíticas para a determinação de alguns pesticidas amplamente utilizados na citricultura brasileira e que têm sido encontrados nos óleos essenciais produzidos pelas indústrias de processamento. Inicialmente, foram realizados testes para avaliação da eletroatividade de três pesticidas (piridafention, cihexatina e bromopropilato) amplamente utilizados no Brasil, mas que são proibidos na maioria dos países importadores, sendo, portanto, de importância estratégica. Utilizando-se a técnica de voltametria cíclica verificou-se que o piridafention apresenta resposta sobre o eletrodo compósito de grafite-poliuretana (GPU), a cihexatina apresentou eletroatividade sobre o eletrodo de filme de bismuto e o bromopropilato não foi eletroativo nas superfícies eletródicas testadas. Varreduras realizadas com voltametria cíclica mostraram que o piridafention apresenta um pico de redução em -0,80 V (vs. EECS) sobre eletrodo compósito de GPU em meio ácido (tampão Britton-Robinson 0,1 mol L-1) com características de processo irreversível. Em seguida, desenvolveu-se uma metodologia eletroanalítica, utilizando a técnica de voltametria de onda quadrada (SWV), com a otimização do pH da solução (1,0) e demais parâmetros da SWV como a frequência (80 s-1), amplitude do pulso (50 mV) e incremento de varredura (ΔEi = 5 mV). Curvas analíticas foram obtidas no intervalo de 1,46 a 17,1 µmol L-1, apresentando boa linearidade, com coeficiente de determinação (r2) de 0,998. Os limites de detecção (LD) e de quantificação (LQ) obtidos foram de 0,27 µmol L-1 e 0,92 µmol L-1, respectivamente. A precisão da metodologia desenvolvida foi avaliada por meio da repetibilidade e a reprodutibilidade e a exatidão determinada pelo erro relativo. Os testes de recuperação realizados pelo método de adição de padrão forneceram valores de 98%. A metodologia eletroanalítica desenvolvida para determinação do piridafention foi aplicada em amostras de óleo essencial de laranja, contaminadas com três níveis de concentração 1,5, 2,9 e 5,9 µmol L-1. Foram avaliados quatro procedimentos de extração líquido-líquido, utilizando água Milli-Q como extrator: i) agitação manual da mistura (10 mL de óleo e 10 mL de água) por 4 minutos com repetição do procedimento por 3 vezes; ii) agitação magnética da mistura (5 mL de óleo e 50 mL de água) por 20 minutos em uma única etapa, à temperatura ambiente; iii) agitação magnética da mistura (5 mL de óleo e 50 mL de água) por 20 minutos em uma única etapa, à temperatura de 45°C; iv) agitação da mistura em mesa orbital com tempo de agitação variando de 5 até 180 minutos. Os melhores resultados foram obtidos com o procedimento utilizando a agitação por mesa orbital (iv), sendo recomendado, portanto, para extração do piridafention em amostras de óleo essencial de laranja. No caso da cihexatina, os testes realizados visando à determinação de uma metodologia eletroanalítica mostraram uma baixa reprodutibilidade do eletrodo filme de bismuto inviabilizando a sua aplicação na eletroanálise da cihexatina. Entretanto, devido à importância da cihexatina e do bromopropilato recomenda-se a realização de mais estudos eletroquímicos com o objetivo de se estabelecer novos métodos de análise. / The citrus production introduced in Brazil during the colonization period and commercially exploited since 1930, is very important for the Brazilian agribusiness. Currently, Brazil is responsible for 50% of the total world citrus production and for about 85% of the citrus world exportation trade, representing an income of about 2.5 billion dollars for the country yearly. The orange juice is the major product of the citrus industry, but other commercially valuable byproducts can be obtained during the manufacturing process, such as the citrus essential oils. These byproduct, located at the orange fruit exocarp, are extracted during the juice production process by cold pressing. Due to the use of pesticides in the citrus production, these agrochemicals can be occasionally presented in extracted essential oil products as unwished residues, which significantly reduce their values in the international market and restrict their insertion in exigent markets as the European, Japanese and North American, for instance. This study aim to develop electroanalytical methodologies for the determination of some pesticides widely employed in the Brazilian citrus production and that has been found in the essential oils produced by the processing industries. Preliminar tests were conducted to evaluate the electroactivity of three pesticides (pyridaphention, cyhexatin and bromopropylate) widely applied in Brazil, but not regulated for use in most of the importing countries. Using the cyclic voltammetry technique, these experiments showed that pyridaphenthion presented a good electrochemical response on the graphite-polyurethane composite electrode (GPU), cyhexatin showed electroactivity on thin bismuth film electrode and bromopropylate was not electroactive on the tested electodes. Studies conducted using cyclic voltammetry showed that pyridaphenthion presents a reduction peak in -0.8 V (vs. ESCE) on GPU in acidic medium (Britton - Robinson buffer 0.1 mol L- 1(BR)) with features of an irreversible process. The electroanalytical methodology for pyridaphenthion analysis was developed using square wave voltammetry (SWV) with optimization of pH (1.0) and the SWV scanning parameters, as pulse frequency (80 s-1), amplitude (50 mV), and increment (ΔEi = 5 mV). An analytical curve was obtained for concentrations ranging from 1.46 a 17.1 µmol L-1, showing good linearity expressed in the determination coefficient (r2) of 0.998. The detection limit (LOD) and quantification limit (LOQ) obtained were 0.27 µmol L-1 and 0.92 µmol L-1, respectively. The precision was evaluated by means its repeatability and reproductibility, while accuracy was assessed by means relative error. Recovery experiments conducted using the standard addition method provided a concentration recovering level of 98%. The electroanalytical methodology developed for pyridaphenthion was applied in citrus essential oil samples spiked with three concentration levels 1.5, 2.9 and 5.9 µmol L-1. Four liquid-liquid extraction procedures were evaluated using only Milli-Q purified water as extracting agent: i) manual stirring of the mixture (10 mL of essential oil and 10 mL of water) during 4 minutes, repeating the procedure three times; ii) magnetic stirring of the mixture (5 mL of essential oil and 50 mL of water) during 20 minutes, in a single step, at room temperature; iii) magnetic stirring of the mixture (5 mL of essential oil and 50 mL of water) during 20 minutes, in a single step, at 45o C; iv) orbital shaking of the mixture (5 mL of essential oil and 50 mL of water) for different period of times varying from 5 to 180 minutes. The best results were obtained with the procedure using the orbital shaking table (iv), which is, therefore, recommended for extraction of pyridaphention residues in citrus essential oils samples. For the cyhexatin, studies carried out aiming to determine an electroanalytical methodology, showed low reproducibility of the bismuth film, preventing its application in the electroanalysis of cyhexatin. However, due to the importance of these pesticides in citrus essential oils production it is recommended additional studies regarding the electrochemistry and electroanalysis of these chemicals.

This thesis is a numerical study of fields within ion traps having segmented electrodes1. The focus is on two cylindrical ion trap structures, two Orbit rap structures and one planar structure which mimics the field of the Orbit rap. In all these geometries, the segments which comprise the electrodes are easily Machin able rings and plates. By applying suitable potential to the different segments, the fields within these geometries are made to mimic the fields in the respective ideal structures. This thesis is divided into 6 chapters. Chapter 1 presents introduction and background information relevant to this work. A brief description of the Quadrupole Ion Trap (QIT) and the Orbit rap is given. The role of numerical simulations in the design of an ion trap geometry is briefly outlined. The motivation of this thesis is presented. The chapter ends by describing the scope of the thesis. Chapter 2 presents a general description of computational methods used throughout this work. The Boundary Element Methods (BEM) is first described. Both 2D and 3D BEM are used in this work. The software for 3D BEM is newly developed and hence 3D BEM is described in more detail. A verification of 3D BEM is presented with a few examples. The Runge-Kutta method used to compute the trajectory of ion is presented. A brief overview of the Nelder-Mead method of function minimization is given. The computational techniques specifically used to obtain the results in Chapter 3, 4 and 5 are presented in the respective chapters. Chapter 3 presents segmented electrode geometries of the Cylindrical Ion Trap (CIT). In these geometries, the electrodes of the CIT are split into number of mini-electrodes and different voltages are applied to these segmented electrodes to achieve the desired field. Two geometries of the segmented electrode CIT will be investigated. In the first, we retain the flat end cap electrodes of the CIT but split the ring electrode into five mini-rings. In the second configuration, we split the ring electrode of the CIT into three mini-rings and 1The term ‘segmented electrode’ used in this thesis has the same connotation as the term ‘split-electrode’ used in Sonalikar and Mohanty (2013). also divide the end caps into two mini-discs. By applying different potentials to the mini-rings and mini-discs of these geometries we will show that the field within the trap can be optimized to desired values. Two different types of fields will be targeted. In the first, potentials are adjusted to obtain a linear electric field and, in the second, a controlled higher order even multipole field are obtained by adjusting the potential. It will be shown that the different potentials to the segmented electrodes can be derived from a single RF generator by connecting appropriate capacitor terminations to segmented electrodes. The field within the trap can be modified by changing the value of the external capacitors. Chapter 4 presents segmented electrode geometries which are possible alternatives for the Orbitrap. Two segmented-electrode structures, ORB1 and ORB2, to mimic the electric field of the Orbitrap, will be investigated. In the ORB1, the inner spindle-like electrode and the outer barrel-like electrode of the Orbitrap are replaced by rings and discs of fixed radii, respectively. In this structure two segmented end cap electrodes are added. In this geometry, different potentials are applied to the different electrodes keeping top-bottom symmetry intact. In the second geometry, ORB2, the inner and outer electrodes of the Orbitrap are replaced by an approximate step structure which follows the profile of the Orbitrap electrodes. For the purpose of comparing the performance of ORB1 and ORB2 with that of the Orbitrap, the following studies will be undertaken: (1) variation of electric potential, (2) computation of ion trajectories, (3) measurement of image currents. These studies will be carried out using both 2D and 3D Boundary Element Method (BEM), the 3D BEM is developed specifically for this study. It will be seen in these investigations that ORB1 and ORB2 have performance similar to that of the Orbitrap, with the performance of the ORB1 being seen to be marginally superior to that of the ORB2. It will be shown that with proper optimization, geometries containing far fewer electrodes can be used as mass analysers. A novel technique of optimization of the electric field is proposed with the objective of minimizing the dependence of axial frequency of ion motion on the initial position of an ion. The results on the optimization of 9 and 15 segmented-electrode trap having the same design as ORB1 show that it can provide accurate mass analysis. Chapter 5 presents a segmented electrode planar geometry named as PORB used to mimic the electric field of the Orbit rap. This geometry has two planes, each plane consisting of 30 concentric ring electrodes. Although the geometry of PORB does not have conventional inner and outer electrodes of the Orbit rap, it will be shown that by selecting appropriate geometry parameters and suitable potentials for the ring electrodes, this geometry can trap the ions into an orbital motion similar to that in the Orbit rap. The performance of the planar geometry is studied by comparing the variation of potential, ion trajectories and image current in this geometry with that in the Orbit rap. The optimization of applied potentials is performed to correct the errors in the electric field so that the variation of axial frequency of ions with their initial position is minimized. Chapter 6 presents the summary and a few concluding remarks

Émanant d’une collaboration entre le laboratoire CNRS du GREMI et le CEA le Ripault, l’objectif de cette thèse est de réaliser une étude exhaustive sur les conditions d’élaboration des électrodes de pile à combustible PEMFC par procédés plasma, dont l’enjeu est d’améliorer l’activité électro-catalytique du catalyseur employé qu’est le platine (Pt). A même quantité, la répartition du platine sur son support se révèle être un critère déterminant sur les performances délivrées par les PEMFCs. De cette observation, plusieurs axes de recherche ont été proposés et chacun d’entre eux a permis d’obtenir de nouveaux résultats. Le régime de pulvérisation magnétron à haute puissance pulsée (HiPIMS) est étudié dans le cas de dépôt de matériaux nobles pures (Pt, Au, Pd) et alliés (Pt5Pd95 et Pt50Pd50) et a permis de révéler une vapeur métallique ionisée conséquente lors du dépôt (10 % à 90 % selon l’élément). Les résultats obtenus sur le régime HiPIMS ont permis la modification de la distribution d’une faible quantité fixée de Pt (20 μg.cm−2) déposée sur la profondeur des couches de diffusion des gaz (GDL), améliorant incidemment les performances des PEMFCs (+80 % à 0.65 V, la tension à puissance nominale). Ce résultat est complété par ceux obtenus sur l’élaboration de catalyseur alliés, notamment sur la disposition du matériel catalytique au niveau de la structure des agrégats (+93 % à 0.65 V pour Pt5Pd95 en dépôts successifs). Une autre étude a permis d’étudier la modification de répartition du Pt en contact avec la membrane électrolyte. La surface de membrane échangeuses de proton est alors initialement structurée. Ces structurations de surface des membranes montrent une amélioration globale des performances PEMFCs pour les architectures CCB (Catalyst Coated Backing) et CCM (Catalyst Coated Membrane) d’un facteur 1.3 jusqu’à 12, respectivement. / From a collaboration between the CNRS laboratory of the CEA and GREMI Ripault, the objective of this thesis is to conduct a complete study on the conditions for producing electrodes of PEM fuel cell by plasma processes in order to improve the electro-catalytic activity of the catalyst (Pt). The platinum atoms on its support appears to be a one of the most important factor determining the performance delivered by the PEMFCs. From this observation, several lines of research have been proposed and each of them has yielded new results. The High Power Impulse Magnetron Sputtering (HiPIMS) process is studied in case of depositions of noble materials (Pt, Au, Pd) and alloy (Pt5Pd95 and Pt50Pd50) and revealed an ionized metal vapor consequent upon deposition (10 % to 90 % depending of the element). The results obtained on the HIPIMS process have allowed a change in the distribution of a small fixed amount of Pt (20 μg.cm−2) deposited on the depth of the gas diffusion layer (GDL), incidentally improving the performance of PEMFCs (+80% at 0.65 V, the voltage at rated power). This result is complemented by those obtained on the development of allied catalysts, especially with the arrangement of the catalytic material on the aggregates structure (+93 % at 0.65 V for Pt5Pd95 in successive deposits). In order to modify the Pt atoms distribution on the membrane support, another study has been realized. The surface of the proton exchange membrane has been structurated before the Pt deposition. Such structuration have shown an increase of the overall performance of PEMFCs in the case of CCB (Catalyst Coated Backing) and CCM (Catalyst Coated Membrane) architecture with an improvement factor of 1.3 up to 12, respectively.

This thesis is completion of whole stage of researches and it is a result of existing need of increase efficiency, utilization rate and service life of lead acid batteries VRLA planned for utilization in hybrid electric vehicles in mode of partial state-of-charge PSoC. During the application of mode PSoC at lead acid battery occurs irreversible sulfation of negative electrodes and thus to loss their charging capability. This phenomenon, according to the latest trend called PCL3, isn´t connected with subsequently referred effects PCL1, PCL2, show up on positive electrodes. Result of this thesis is finding a new types of additives, determine their optimum amount and size in such a way that innovated composition of negative active materials be able to resist sulfation of negative electrode during operation in mode PSoC. Part of the effort to clarify actions ongoing on negative active material and causes non-returnable sulfation electrodes is also monitoring of structural changes electrode active material by using environmental scanning electron microscope, which helped to clarify processes related with loss of capacity in mode PSoC. Special attention during reserches was focused on study of the properties contact layers between collector and electrodes active material and itself active materials lead-acid battery druring exploitation. There were gain new information about influence repeated cycling of (charging, discharging) the critical area of the electrodes. Measurements was carried out on specially prepared experimental electrodes DC Difference Method, this enabled obtain data in situ.

The main objective of this Diploma Thesis is studying the possibility of detection of nitro derivatives of aromatic hydrocarbons by using chemically modified working electrodes in electrochemical analysis. Compounds analyzed in this work were 1-nitronaphthalene and 6- nitrochrysene - these compounds were chosen on previous experience with surface modified working electrodes (the chemical/physical properties of these substances). All the analyses were performed by using differential pulse voltammetry (DPV) on hanging mercury drop electrode (HMDE) in classic three-electrode system. The original premise of chemical modification of electrode surface is the change of its selectivity towards different compounds - meaning the change of the electrochemical response. The modification agent used in this thesis is 1-octanethiol. Its thiol group offers great potential of strong interaction with the metal surface of the mercury electrode. Voltammetric responses of both compounds were recorded in acidic, neutral and basic solutions (pH=2, pH=7, pH=12) including the responses when the electrode surface was modified. Next objective was the optimization of the modification procedure itself (transferring of the mercury drop from one media to another without damaging or tearing it off from the capillary orifice)....

Widerstandspunktschweißen ist das dominante Fügeverfahren in der Karosserieherstellung. Der steigende Wunsch nach mehr Sicherheit und gleichzeitig nach einem möglichst leichten Fahrzeug, führt zur Verwendung hochfester Stähle. Mit der Festigkeit steigen die Anforderungen an die Prozesssteuerung und die Punktschweißzangen. Die Simulation des Punktschweißprozesses wird verwendet, um einen materialgerechten Schweißprozess zu entwickeln, sowie Zeit und Material für entsprechende Versuche einzusparen. In der Simulation können physikalische Größen ermittelt werden, welche am Schweißpunkt nicht messbar sind. Im Vortrag wird ein FEM-Modell vorgestellt, welches den Widerstandspunktschweißvorgang simuliert. Die erste Ausbaustufe des Modells umfasst die zu fügenden Bleche und das Elektrodenpaar der Punktschweißzange. Die Elektrodenkraft wird zu Beginn der Schweißsimulation auf die Elektrode aufgebracht und über den Prozesszyklus als konstant angenommen. Diese Annahme steht im Widerspruch zu in der Praxis gemessenen Elektrodenkraftverläufen. Diese weisen eine dynamische Änderung über der Schweißzeit auf. Der Unterschied zwischen gemessener und in der Simulation vorgegebener konstanter Elektrodenkraft war die Motivation zur Erstellung eines mechanischen Maschinenmodells, welches im Vortrag präsentiert wird. Das Modell ist mit der Schweißprozesssimulation gekoppelt und errnöglicht die numerische Untersuchung der Wirkung mechanischer Maschinenparameter auf ein Punktschweißergebnis. Erste Ergebnisse der Schweißprozesssimulation unter Berücksichtigung des mechanischen Maschinenverhaltens werden vorgestellt und diskutiert.

The purpose of this work is to study the saturation of the sodium NaCl melt, dissolve the titanium rod, and restore TiCl2 in the electrolyte volume with a Na-NaCl melt to develop an electrochemical technology for producing titanium powders. To substantiate the electrode processes, an attempt was made to create reference electrodes for the systems under study. According to the published data, the equations of temperature dependences of the standard, conventional-standard and redox potentials and the concentration dependence of the equilibrium potentials of titanium in molten sodium chloride, which were used in the analysis of polarization curves, were calculated. The kinetics of electrode processes in a sodium chloride melt is studied when metallic titanium is dissolved in it and when sodium is deposited on the iron cathode. An explanation of the processes occurring at the electrodes is given. Powders of metallic titanium are obtained. / Целью данной работы является исследование насыщения расплава NaCl натрием, растворение титанового стержня и восстановление TiCl2 в объеме электролита расплавом Na-NaCl для разработки электрохимической технологии получения порошков титана. Для обоснования электродных процессов, предпринята попытка созданы электроды сравнения для изучаемых систем. По литературным данным рассчитаны уравнения температурных зависимостей стандартного, условно-стандартного и окислительно-восстановительных потенциалов и концентрационной зависимости равновесных потенциалов титана в расплавленном хлориде натрия, которые использовались при анализе поляризационных кривых. Изучена кинетика электродных процессов в расплаве хлорида натрия при растворении в нем металлического титана и при осаждении натрия на железном катоде. Дано объяснение происходящих на электродах процессов. Получены порошки металлического титана.

Целью диссертационного исследования является изучение процессов восстановления нитрогруппы в препаратах азоло-азинового ряда с применением электрохимических методов и ЭПР-спектроскопии. Для достижения стабильных и воспроизводимых данных была разработана методика эксперимента. Рассмотрены вопросы электровосстановления фармпрепаратов содержащих нитрогруппу в своем строении и применение ЭПР – спектроскопии и электрохимических методов анализа, в частности вольтамперометрии, для установления механизма восстановления лекарственных веществ в теле человека. В ходе экспериментальной части установлена природа происходящих процессов, в том числе, природа лимитирующей стадии, проведен расчет количества электронов, принимающих участие в процессах электровосстановления основного вещества препаратов TRIAZAVIRIN® и TRIAZID®. Предложены вероятные механизмы протекания исследуемого процессов восстановления нитрогруппы исследуемых соединений. / The main substances of the newest Russian antiviral drugs, the aziolo-azine series TRIAZAVIRIN® and TRIAZID®, served as the research subjects. Objective: to study the processes of reduction of the nitro group in these compounds using electrochemical methods and EPR spectroscopy. An analysis of the literature data showed that the pharmaceutical activity of preparations containing a nitro group is due to its reduction. Electrochemical methods of analysis make it possible to study the in vitro transformation of the preparation as close as possible to the processes taking place with the drug in vivo. The method of EPR-spectroscopy allows obtaining reliable data on the free radical formed during the reaction, which can be a determining factor of the biological activity of the preparation. These methods were taken as a basis for studying the processes of nitro group reduction, which is a part of the basic substances of TRIAZAVIRIN® (TRZ) and TRIAZID® (TZ) preparations. The processes of nitro group reduction in TRZ and TZ molecules were studied using voltammetry and EPR spectroscopy. It has been established that the rate of reduction of the nitro group TRZ is controlled by diffusion, the process of reduction of the nitro group of the preparation is stepwise, irreversible and proceeds at a potential of -0.35 V through the formation of an anion radical with addition of 4e. It is shown that the rate of reduction of the nitro group of TZ is controlled by diffusion. The single-wave reduction process of the nitro group TZ at a potential of 6 -0.65 V is irreversible, goes through the formation of an anion radical with addition of 6e. Possible schemes for the recovery of the nitro group of the basic substances of TRIAZAVIRIN® and TRIAZID® preparations are proposed.

Объектом исследования служило лекарственное вещество 5-метил-6-нитро-7-оксо-1,2,4-триазоло[1,5-а] пиримидинид аргинина моногидрат с условным названием «Триазид» (ТД). Цель работы: разработка чувствительного электрохимического сенсора для количественного определения лекарственного вещества 5-метил-6-нитро-7-оксо-1,2,4-триазоло[1,5-а] пиримидинид аргинина моногидрата. Показана возможность применения толстопленочных углеродсодержащих электродов для вольтамперометрического определения исследуемого вещества. Изучено влияние модифицирования поверхности толстопленочных электродов на их электрохимические характеристики для количественного определения лекарственного вещества в испытуемом растворе методами циклической вольтамперометрии, прямой вольтамперометрии в квадратно-волновом режиме, спектроскопии электрохимического импеданса и сканирующей электронной микроскопии. Исследовано влияние срока хранения электрохимического сенсора для количественного определения ТД методом прямой вольтамперометрии в квадратно – волновом режиме и спектроскопии электрохимического импеданса. Выбран чувствительный электрохимический сенсор для количественного определения ТД. Выполнена статистическая обработка результатов анализа. Проведено вольтамперометрическое определение ТД в фармацевтической субстанции «Триазид». Согласно ОФС.1.1.0012.15 и ОФС ОФС.1.1.0013.15 Государственной Фармакопеи РФ XIII издания, был сделан вывод о соответствии аналитической методики количественного определения ТД в фармацевтической субстанции «Триазид» заявленным критериям приемлемости. / The object of the study was the drug 5-methyl-6-nitro-7-oxo-1,2,4-triazolo [1,5-a] pyrimidinide arginine monohydrate with the code name «Triazid» (TD). Objective: development of a sensitive electrochemical sensor for the quantitative determination of the medicinal substance 5-methyl-6-nitro-7-oxo-1,2,4-triazolo [1,5-a] pyrimidinide of arginine monohydrate. The possibility of using thick-film carbon-containing electrodes for voltammetric determination of the test substance is shown. The effect of modification of the surface of thick-film electrodes on their electrochemical characteristics was studied for the quantitative determination of the drug in the test solution by the methods of cyclic voltammetry, direct voltammetry in the square-wave mode, electrochemical impedance spectroscopy, and scanning electron microscopy. The influence of the shelf life of an electrochemical sensor for the quantitative determination of TD by direct voltammetry in a square-wave mode and electrochemical impedance spectroscopy has been investigated. A sensitive electrochemical sensor was selected for the quantitative determination of TD. Statistical processing of the analysis results has been performed. Voltammetric determination of TD in the pharmaceutical substance «Triazid» was carried out. According to OFS.1.1.0012.15 and OFS OFS.1.1.0013.15 of the State Pharmacopoeia of the Russian Federation of the XIII edition, it was concluded that the analytical method for quantitative determination of TD in the pharmaceutical substance «Triazid» meets the stated acceptance criteria.

No description available.