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Search results for: SURFACE CHEMISTRY
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Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences
PublicationNanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...
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Wykorzystanie testu TOXALERT do oceny stanu wód powierzchniowych wokół zakładu przemysłowego. Application of the TOXALERT test to the evaluation of the state of surface waters arround an industrial plant
PublicationW pracy przedstawiono badania, których celem była próba oceny wpływu działalności gospodarczej prowadzonej przez zakład przerobu ropy naftowej na elektryczność wód powierzchniowych wokół zakładu. Badano także skuteczność procesu oczyszczania ścieków, powstających w związku z tą działalnością w przyzakładowej oczyszczalni. Toksyczność pobranych próbek wód oznaczano za pomocą testu bakteryjnego z zastosowaniem organizmów Vibrio fischeri....
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Development and optimization of simplified method of fast sequential HR-CS-FAAS analysis of apple juices on the content of Ca, Fe, K, Mg, Mn and Na with the aid of response surface methodology
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Chemometrics and Statistics | Multicriteria Decision Making
PublicationThis contribution describes the application of Multicriteria Decision Making tools in analytical chemistry. The general scheme of MCDM is presented to show its general steps. The most frequently applied in analytical sciences MCDM techniques – AHP, ELECTRE, PROMETHEE and TOPSIS – are briefly described and their advantages and disadvantages are discussed. The applications in analytical chemistry are selection of an appropriate...
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Miniaturized solid phase microextratcion
PublicationWithout any doubt analytical laboratories have an essential role in environmental protection due to the fact that they takes an active part in the monitoring pollutants present in air, water or soil. From the other side, the analytical activity is involved in the generation of toxic waste what is associated with the use of not eco-friendly reagents and solvents. For these reasons, green analytical chemistry (GAC) was introduced...
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Comparative Greenness Evaluation
PublicationGreenness of analytical procedure is multivariable aspect as many greenness criteria should be taken into consideration. On the other hand, modern analytical chemistry offers dozens of analytical procedures, based on different sample preparation and final determination techniques that are used for the determination of a given analyte in a given matrix. For such complex decision-making processes, multi-criteria decision analysis...
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Recent Developments in the Synthesis of Unsymmetrical Disulfanes (Disulfides). A Review
PublicationThe synthesis of unsymmetrical disulfanes is an important transformation in organic synthesis and medicinal chemistry. The current review is intended to summarize achievements in the synthesis of unsymmetrical disulfanes over the last decade (2004–2014).
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Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublicationOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
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The role of water in deep eutectic solvent-base extraction
PublicationDeep eutectic solvents (DESs) are currently being used in different sectors, such as electrochemistry, electrodeposition, organic synthesis, nanoparticle preparation, bioactive compound separation, etc. Their use in analytical chemistry has only recently begun to expand. Despite the publication of a sufficient number of DES-based analytical extraction procedures, some details, such as interaction of DESwith the sample and target...
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A derivatisation agent selection guide
PublicationThe development of new tools for providing high quality information in a cost-effective and expeditious way is one of the main aims of analytical chemistry. Remarkably, the introduc- tion of the 12 principles of green chemistry paved the way forward for the development of analytical methodologies that are, ideally, inherently safe for the operator and the environ- ment, with the least possible consumption of energy and chemicals,...
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New matrix-free reference material for ethene in the form of optical fibres
PublicationReference materials are indispensable in the qualitycontrol and quality assurance of analytical measurements. Onenovel approach to the generation of standard gaseous mixturesof toxic, reactive, volatile, labile, and malodorous substancesinvolves thermal decomposition or rearrangement, under definedtemperature conditions, of compounds immobilized, bychemical bonding, on the surface of an appropriate carrier torelease specific amounts...
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Shape-dependent enhanced photocatalytic effect under visible light of Ag3PO4 particles
PublicationSilver phosphate (Ag3PO4) could be considered as visible light induced photocatalyst for pollutants degradation, due to its narrow band gap (∼2.4 eV). However, Ag3PO4 photoactivity depends on surface properties and synthesis route. In this study, differently shaped Ag3PO4 photocatalysts have been synthesized through the precipitation, ion exchange, soft-chemical or hydrothermal method. To correlate surface properties with photoactivity all...
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Hasse diagram as a green analytical metrics tool: ranking of methods for benzo[a]pyrene determination in sediments
PublicationThis study presents an application of the Hasse diagram technique (HDT) as the assessment tool to select the most appropriate analytical procedures according to their greenness or the best analytical performance. The dataset consists of analytical procedures for benzo[a]pyrene determination in sediment samples, which were described by 11 variables concerning their greenness and analytical performance. Two analyses with the HDT...
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Trends in the new generation of green solvents in extraction processes
PublicationAnalytical chemistry, like other scientific fields, has undergone a number of changes to make it more consistent with the concept of sustainable development. Among the various steps of chemical analysis, without a doubt, sample preparation is the bottleneck in regard to following a green protocol, especially in terms of solvent consumption. Therefore, many attempts have been made to improve the environmental friendliness of this...
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Application of molecularly imprinted polymers in analytical chiral separations and analysis
PublicationOver the last two decades the process of development and application of a new types of molecular imprinted polymer (MIP) sorbents in the field of analytical chemistry have been widely described in the literature. One of the new trends in analytical chemistry practice is the use of new types of MIP sorbents as specific sorption materials constituting the stationary phase in advanced separation techniques. The following review paper...
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How can analysts use multicriteria decision analysis?
PublicationProper decision making in multifacitated situation is very challenging task. It is especially difficult if there are many alternatives and criteria that are often contradictory. Analytical chemistry and related sciences involve many situations where decisions on complex problems are made. The support tools may be the use of MCDA (Multi-criteria Decision Analysis) algorithms. They formalize the decision process, make it transparent...
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A review of amide bond formation in microwave organic synthesis
PublicationMicrowave-Assisted Organic Synthesis (MAOS) is one of the most current trends in organic chemistry. Herein, both the most popular and new approaches in microwave-syntheses of very important linkage in Nature - amide bond - are overviewed and compared with conventional synthetic routes.
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Why the Solvation Water around Proteins Is More Dense than Bulk Water
PublicationThe main aim of this work is to propose a rational explanation of the commonly observed phenomenon of increasing water density within solvation shell of proteins. We have observed that the geometry of the water–water hydrogen bond network within solvation layer differs from the one in bulk water, and it is the result of interactions of water molecules with protein surface. Altered geometry of the network reflects changes in the...
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Why the solvation water around proteins is more dense than bulk water
PublicationThe main aim of this work is to propose a rational explanation of commonly observed phenomenon of increasing water density within solvation shell of proteins. We have observed that geometry of the water-water hydrogen bond network within solvation layer differs from the one in bulk water and it is the effect of interactions of water molecules with protein surface. Altered geometry of the network reflects changes in the structure...
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Similar concentration of surfactants in rural and urban areas
PublicationSince surfactants are used in various products, they end up in surface and wastewater. Surfactants may therefore impact ecosystems and living organisms. Actually, only few anionic surfactants and some alkylphenols are regulated. There is no comprehensive evaluation of surfactants in the atmosphere, surfaces and waters of areas of increasing anthropic levels. Here, we measured the levels of cationic, anionic and nonionic surfactants...
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Application of different modes of nanoscale impedance microscopy in materials research
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An effective Hamiltonian for sulfur adsorption at Au(100) surface
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Evaluation of organic coatings condition with AFM-based method
PublicationThe paper presents an atomic force microscopy (AFM)-based approach to evaluation of local protective properties of organic coatings. Apart from topography, it provides local ac and dc characteristics of examined coating. The method consists in application of ac voltage perturbation signal between conductive AFM tip and coated metal substrate. The resulting current is used to determine local impedance characteristics. Both impedance...
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Nanotubular oxide layers and hydroxyapatite coatings on ‘Ti–13Zr–13Nb’ alloy
PublicationThe presented research was aimed to determine the mechanical properties of the nanotubular oxide layer covered with hydroxyapatite coating. The Ti–13Zr–13Nb alloy was oxidised in 1M phosphoric acid with an addition of 0?5% HF for HF solution at 20 V voltage. The electrochemically assisted deposition of hydroxyapatite was performed at cyclic polarisation in NH4H2PO4 and CaCl2 solution at 80uC. The mechanical properties were determined...
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Application of different modes of nanoscale impedance microscopy in materials research
PublicationIn recent years, there is noticeable interest in application of various types of scanning probe microscopy in material science research. One of them is contact atomic force microscopy combined with local impedance measurements, known as nanoscale impedance microscopy. Literature references present its application in investigations of new materials, microelectronics diagnostics, or research of protective coatings performance. In...
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Diamond surface modification following thermal etching of Si supported hydrogenated diamond films by DBr
PublicationZbadano, wykorzystując spektroskopię oscylacyjną (HREELS - High Resolution Electron Energy Loss Spectroscopy) modyfikacje chemiczne powierzchni wodorowanego diamentu, umieszczonego na podkładzie krzemowym i wystawionego na działanie DBr a następnie podgrzanego do temp. powyżej 600 st.K. Przedstawiona procedura powoduje tworzenie się węglika krzemu SiC na powierzchni warstwy diamentowej, co jest widoczne na widmie HREEL jako dwa...
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Properties of Composite Oxide Layers on The Ti13Nb13Zr Alloy
PublicationThe development of composite oxide layers on the Ti13Nb13Zr alloy, their structure and properties have been demonstrated. Two subsequent methods were applied to prepare the composite layers. During the first stage gas oxidation produced a solid oxide layer, and subsequently oxide nanotubes were produced by using an electrochemical method. Scanning electron microscopy (SEM), chemical analysis, energy dispersive X-ray spectroscopy...
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Fluconazole resistant Candida auris clinical isolates have increased levels of cell wall chitin and increased susceptibility to a glucosamine-6-phosphate synthase inhibitor
PublicationIn 2009 Candida auris was first isolated as fungal pathogen of human disease from ear canal of a patient in Japan. In less than a decade, this pathogen has rapidly spread around the world and has now become a major health challenge that is of particular concern because many strains are resistant to multiple class of antifungal drugs. The lack of available antifungals and rapid increase of this fungal pathogen provides an incentive...
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Impedance evaluation of coatings from biobased material
PublicationThe authors propose a modification of sodium caseinate edible coating for foodstuff protection. The aim was to improve the film’s barrier properties. It was achieved by the addition of propolis, which is a natural, environmentally friendly product known from its intrinsic sealing action. In the next step, propolis-admixed sodium caseinate films were exposed to elevated temperature for 10 min. This approach was meant to improve...
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Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublicationThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
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Facile formation of self-organized TiO2 nanotubes in electrolyte containing ionic liquid - ethylammonium nitrate and their remarkable photocatalytic properties
PublicationThe oriented TiO2 nanotube arrays (NTs) are identified as a stable, active and recyclable photocatalytic surface. However, their photoactivity is strictly depended on morphology (especially length), which could be controlled by anodic oxidation parameters, including electrolyte properties. To control the morphology, were successfully synthesized a series of NTs by a novel approach where ionic liquid (IL), ethylammonium nitrate...
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Long‐time scale simulations of virus‐like particles from three human‐norovirus strains
PublicationThe dynamics of the virus like particles (VLPs) corresponding to the GII.4 Houston, GII.2 SMV, and GI.1 Norwalk strains of human noroviruses (HuNoV) that cause gastroenteritis was investigated by means of long-time (about 30 μs in the laboratory timescale) molecular dynamics simulations with the coarse-grained UNRES force field. The main motion of VLP units turned out to be the bending at the junction between the P1 subdomain (that...
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Understainding solid-phase microextraction: key factors influencing the extraction process and trends in improving the technique
PublicationAnalytical chemists are faced with the daunting challenges of accurately monitoring the state of the environment and the processes taking place in it and of determining an enormous range of analytes often present in trace and ultratrace amounts in sample matrixes with complex or variable compositions. Further challenges are presented by the need to introduce new methodologies into current analytical practice and equipment to comply...
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Overview of the three multicriteria approaches applied to a global assessment of analytical methods
PublicationCritical and global evaluation of analytical methods should be one of the primary goals in analytical chemistry. A holistic approach, however, requires a look at the varied features: commonly discussed validation criteria, often underrated practical and economic aspects, and typically overlooked compliance with the principles of green analytical chemistry. Carrying out such an assessment in a critical and transparent way is extremely...
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Experimental and Quantum Chemical Evaluation of 8-Hydroxyquinoline as a Corrosion Inhibitor for Copper in 0.1 M HCl
PublicationThe corrosion inhibition properties of 8-hydroxyquinoline (8-HQ) in 0.1 M HCl for copper have been investigated by using experimental (electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS), and potentiodynamic polarization) and theoretical methods complemented by surface morphological examination with the aid of scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy...
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Band Gap Engineering toward Semimetallic Character of Quinone-Rich Polydopamine
PublicationSemiconductor|melanin interfaces have received increasingly more attention in the fields of photocatalysis and applied electrochemistry because of their facile synthesis, unique electrical properties, and strong capability toward photosensitization. In this work, we describe the electropolymerization of quinone-rich polydopamine (PDA) on the surface of hydrogenated TiO2 nanotubes with enhanced photoactivity in the visible spectrum....
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Ordered TiO2 nanotubes with improved photoactivity through self-organizing anodization with the addition of an ionic liquid: effects of the preparation conditions
PublicationModifying the geometric and surface parameters of oriented TiO2 nanotubes (NTs) is beneficial to the utilization of solar energy for chemical reactions, and this performance may be further improved. Thus, the effects of adding an ionic liquid (IL), 1-butylpiridinium chloride [BPy][Cl], and the effects of the water content and preparation conditions on the surface morphological, physicochemical, photocatalytic and photoelectrochemical...
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Charge dependence of fragmentation process induced by ion collisions with furan molecule
PublicationThe goal of this work is to describe the system evolution after ion-molecule interaction. We combine different quantum chemistry and statistical mechanics approaches in order to give extended description of the process. Herein we report on a recent study of the fragmentation mechanism of neutral, singly- and doubly-ionized furan molecule in the gas phase.
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Study of Cloud Water Samples Collected over Northern Poland
PublicationThe paper gives the results of the first studies on the chemistry of cloud water collected during 3 mo (Aug.–Oct. 2010) in the free atmosphere over the area to the south of the Tri-City (Gdansk-Sopot-Gdynia) conurbation on the Gulf of Gdansk, Poland. Taken from cumulus, stratus, and stratocumulus clouds by means of an aircraft-mounted collector, the water samples were analyzed for the following contaminants: anions (chlorides,...
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AGREE—Analytical GREEnness Metric Approach and Software
PublicationGreen analytical chemistry focuses on making analytical procedures more environmentally benign and safer to humans. The amounts and toxicity of reagents, generated waste, energy requirements, the number of procedural steps, miniaturization, and automation are just a few of the multitude of criteria considered when assessing an analytical methodology’s greenness. The use of greenness assessment criteria requires dedicated tools. We...
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CLICK 'n' Sleep: Light-Switch Behavior of Triazole-Containing Tris(bipyridyl)ruthenium Complexes
PublicationA set of RuII complexes incorporating triazole subunits are presented. They show a solvent-dependent light-switch effect. Theoretical calculations revealed the excited states involved in the emission process. The findings are highly important for future design of light-switch sensors and suggest a severe restriction for functional photomolecular devices synthesized by CLICK chemistry.
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Consequences of suboptimal design of Building Integrated Photovoltaic Installation – a case study for Gdansk, Poland
PublicationThe carried out analysis concerns 2 kWp building integrated photovoltaic installation (BIPV) at the Chemistry Faculty of Gdansk University of Technology. It was proven that the generated energy data for every month diverge significantly from the expected vales. It is corelated with suboptimal orientation of the installation itself, as well as with the tilt angle varying from optimal.
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Texture or Linker? Competitive Patterning of Receptor Assembly toward Ultra-Sensitive Impedimetric Detection of Viral Species at Gold-Nanotextured Titanium Surfaces
PublicationIn this work, we study the electrodes with a periodic matrix of gold particles pattered by titanium dimples and modified by 3-mercaptopropionic acid (MPA) followed by CD147 receptor grafting for specific impedimetric detection of SARS-CoV-2 viral spike proteins. The synergistic DFT and MM/MD modeling revealed that MPA adsorption geometries on the Au–Ti surface have preferential and stronger binding patterns through the carboxyl...
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Reactions of methyl radicals with silica supported silver nanoparticles in aqueous solutions
PublicationSilica supported silver nanoparticles (Ag°–SiO2 –NCs, NCs=nanocomposites) suspended in aqueous solutions are efficient catalysts for the dimerization of methyl radicals to produce ethane, while bare silica is quite inert towards the interaction with methyl radicals. In the presence of small amounts of ethanol adsorbed on the SiO2 surface, the reaction path with methyl radicals is changed and methane is formed as the major product.
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Mechanism of Li nucleation at graphite anodes and mitigation strategies
PublicationLithium metal plating is a critical safety issue in Li-ion cells with graphite anodes, and contributes significantly to ageing, drastically limiting the lifetime and inducing capacity loss. Nonetheless, the nucleation mechanism of metallic Li on graphite anodes is still poorly understood. But in-depth understanding is needed to rationally design mitigation measures. In this work, we conducted FirstPrinciples studies to elucidate...
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Electrochemical performance of thin free-standing boron-doped diamond nanosheet electrodes
PublicationIn the following work we describe preparation and the electrochemical performance of thin and free-standing heavy boron-doped diamond (BDD) nanosheets. The investigated foils were deposited on Ta substrate using microwave plasma-enhanced chemical vapor deposition technique (MPECVD). Foils of two B-dopant densities were investigated, obtained on the base of 10 k and 20 k ppm [B]/[C] ratio in the gas admixture. The obtained foils...
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Selected issues related to the toxicity of ionic liquids and deep eutectic solvents—a review
PublicationGreen Chemistry plays a more and more important role in implementing rules of sustainable development to prevent environmental pollution caused by technological processes, while simultaneously increasing the production yield. Ionic liquids (ILs) and deep eutectic solvents (DESs) constitute a very broad group of substances. Apart from many imperfections, ILs and DESs have been the most promising discoveries in the world of Green...
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Deep eutectic solvents in analytical sample preconcentration Part B: Solid-phase (micro)extraction
PublicationOne of the key challenges of modern analytical chemistry is the monitoring of trace amounts of contaminants using sensitive and selective instrumental techniques. Due to the variety and complexity of some samples, it is often necessary to properly prepare a sample and to perform a preconcentration of trace amounts of analytes. In line with the principles of Green Analytical Chemistry (GAC), it is important for an analytical procedure...
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Application of TOPSIS for Selection and Assessment of Analytical Procedures for Ibuprofen Determination in Wastewater
PublicationThis paper describes the possible implementation of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as green analytical chemistry metrics tools. TOPSIS is one of the multi-criteria decision analysis (MCDA) tools that is applied in the selection of the best alternative from many possible. In this case we have applied it to assess the nineteen analytical procedures for ibuprofen determination in wastewater...
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Duhem and Natanson: Two Mathematical Approaches to Thermodynamics
PublicationIn this article, the previously unrecognized contributions of Pierre Duhem and Ladislavus Natanson in thermodynamics are shown. The mathematical remodelling of a few of their principal ideas is taken into consideration, despite being neglected in the literature. To emphasize these ideas in an appropriate epistemological order, it would be crucial to first revalue and reconstruct some underrepresented parts of the proceedings process...