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Search results for: CHEMICAL ANALYSIS
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublicationIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Comparison of Headspace Solid-phase Microextraction, Headspace Single-drop Microextraction and Hydrodistillation for Chemical Screening of Volatiles in Myrtus Communis L
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Chemical Structure and Thermal Properties versus Accelerated Aging of Bio-Based Poly(ether-urethanes) with Modified Hard Segments
PublicationAging of polymers is a natural process that occurs during their usage and storage. Predicting the lifetime of polymers is a crucial aspect that should be considered at the design stage. In this paper, a series of bio-based thermoplastic poly(ether-urethane) elastomers (bio-TPUs) with modified hard segments were synthesized and investigated to understand the structural and property changes triggered by accelerated aging. The bio-TPUs...
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The influence of chemical composition of amide block on the thermal properties and structure of terpoly(ester-b-ether-b-amide) elastomers
PublicationMultiblock terpolymers-(PBT-b-PTMO-b-PA12,10)(n)- constituting the polymer systems, in which one of the three blocks (PBT) does not dissolve in PA12,10 block (hard phase) and, depending on its molecular weight is slightly soluble in PTMO block (soft phase), have been obtained. The DSC method was applied to investigate the thermal properties of these polymers and it was found that PBT block acts as an element that produces stiffness...
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The impact of thermomechanical and chemical treatment of waste Brewers’ spent grain and soil biodegradation of sustainable Mater-Bi-Based biocomposites
PublicationDue to the massive plastic pollution, development of sustainable and biodegradable polymer materials is crucial to reduce environmental burdens and support climate neutrality. Application of lignocellulosic wastes as fillers for polymer composites was broadly reported, but analysis of biodegradation behavior of resulting biocomposites was rarely examined. Herein, sustainable Mater-Bi-based biocomposites filled with thermomechanically-...
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From ashes to porous hierarchical nanocarbon electrode: Upcycling secondary waste materials through self-catalytic chemical vapour deposition
PublicationMetal and metal oxide particles are abundant in various ash-based wastes. Utilizing these as catalyst sources for the fabrication of carbon nanomaterials could present a valuable approach to reduce our reliance on non-renewable and costly catalyst sources, thereby facilitating large-scale nanomaterial production. In this context, secondary waste materials (SWMs) are by-products resulting from the (complete or partial) combustion...
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Chemical variability of Rhododendron tomentosum (Ledum palustre) essential oils and their pro-apoptotic effect on lymphocytes and rheumatoid arthritis synoviocytes
PublicationRhododendron tomentosum (Ledum palustre) is an aromatic plant traditionally used for alleviating rheumatic complaints which makes it a potential candidate for a natural drug in rheumatoid arthritis (RA) treatment. However, the effects of plants’ volatiles on apoptosis of synovial fibroblasts and infiltrating leucocytes of RA synovia, have not been reported. Volatile fraction of R. tomentosum is chemically variable and chemotypes...
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Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI - SPME coupled with GC-MS
PublicationA simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have...
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Chemical investigation on the mechanism and kinetics of the atmospheric degradation reaction of Trichlorofluoroethene by OH⋅ and Its subsequent fate in the presence of O2/NOx
PublicationThe M06-2X/6-311++G(d,p) level of theory was used to examine the degradation of Trichlorofluoroethene (TCFE) initiated by OH⋅ radicals. Additionally, the coupled-cluster single-double with triple perturbative [CCSD(T)] method was employed to refine the single-point energies using the complete basis set extrapolation approach. The results indicated that OH-addition is the dominant pathway. OH⋅ adds to both the C1 and C2 carbons,...
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The Baltic Sea as a dumping site of chemical munitions and chemical warfare agents
PublicationW pracy przedstawiono problem składowania w Morzu Bałtyckim aminucji chemicznej i bojowych środków trujących. Przedstawiono typy oraz charakterystykę BST składowanych na dnie Morza Bałtyckiego. Omówiono potencjalne zagrożenia dla środowiska abiotytcznego oraz dla organizmów żywych związanych z tego typu składowiskami. Przedstawiono również podstawowe informacje o procedurach analitycznych, które mogą być wykorzystane do wykrywania...
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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
PublicationDue to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed:...
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Interface analysis of compatibilized polymer blends
PublicationThis chapter seeks to address the interface location in the compatibilized polymer blends and paves the way for quantitative analysis of interface in terms of interfacial tension and interfacial adhesion to provide support for understanding the relationship between morphology and ultimate properties in the compatibilized polymer blends through the lens of interface. Since understanding and analysis of interfacial phenomena in the...
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Metabolism of chemical carcinogens
PublicationW rozdziale omówiono szlaki przemian metabolicznych wielu grup związków rakotwórczych z uwzględnieniem zarówno reakcji aktywacji jak i detoksykacji. SzczegÓlną uwagę poświęcono związkom rakotwórczym występującym w żywności.
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The Application of Cluster Analysis in the Assessment of the Weldability of Unalloyed Steels
PublicationNon-alloy steels constitute a large group of steels characterised by diversified chemical composition, structural morphology and a wide range of mechanical properties (determining weldability). The paper presents results of multidimensional analyses (based on cluster analysis) of 110 selected unalloyed steel grades. Properties adopted as diagnostic features included the chemical composition, mechanical properties (yield point)...
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Elucidation of chemical compounds in different extracts of two Lavandula taxa and their biological potentials: Walking with versatile agents on the road from nature to functional applications
PublicationDue to their health-promoting and nutraceutical properties, lavenders are frequently employed in the food and pharmaceutical industries. Here, we focused on investigate the chemical profile of hexane, MeOH, and water extracts of leaf, flower, and root of L. pedunculata and L. stoechas and to assess their antioxidant, enzyme inhibitory, and antibacterial properties. The highest total polyphenolic and flavonoids contents were recorded...
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Analysis of MArkers of Exposure to Constituents of Environmental Tobacco Smoke (ETS)
PublicationTobacco smoke is a complex mixture of more than 4000 chemical compounds, many of which are harmful to human health. These compounds belong to various chemical classes, including amides, imides, lactams, carboxylic acids, aldehydes, ketones, alcohols, phenols, amines, hydrocarbons, ethers, and inorganic compounds. There are three types of tobacco smoke streams: the mainstream, the sidestream, and environmental tobacco smoke (ETS)....
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Modal analysis of cylindrical steel tanks
PublicationCylindrical steel tanks are very popular structures used for storage of products of chemical and petroleum industries. Their safety and reliability is crucial because any failure could have serious consequences. The aim of present paper is to show the results of the first phase of investigation of seismic behaviour such structures. Modal analysis using Finite Element Method (FEM) for three models of real tanks used in Poland has...
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Sources and composition of chemical pollution in Maritime Antarctica (King George Island), part 2: Organic and inorganic chemicals in snow cover at the Warszawa Icefield
PublicationThe study area is located on King George Island, where 90% of the area is permanently glaciated. This study provides a comprehensive analysis of the inorganic and organic chemistry of snow cover in the icefield and a comparison against previous results obtained in fresh water. Snow samples were collected in the summer of 2017 in the Warszawa Icefield area. Sampling points are located along two transects: between the Arctowski Polish...
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Chemical Composition and Structure of Foods
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Fluctuation - enchanced chemical sensing
PublicationCzułość i selektywność sensorów gazu może ulec poprawie jednocześnie gdy wykorzysta się informację zawartą w szumach występujących w sensorze. W pracy opisano szczegółowo kilka metod stosowanych do analizy szumów sensorów gazu. Przedstawiono wyniki ostatnich eksperymentów przeprowadzonych na komercyjnych sensorach gazu Taguchi, sensorach SAW oraz MOS-FET.
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APPLICATION OF CHEMOMETRIC ANALYSIS TO THE STUDY OF SNOW AT THE SUDETY MOUNTAINS, POLAND
PublicationSnow samples were collected during winter 2011/2012 in three posts in the Western Sudety Mountains (Poland) in 3 consecutive phases of snow cover development, i.e. stabilisation (Feb 1st), growth (Mar 15th) and its ablation (Mar 27th). To maintain a fixed number of samples, each snow profile has been divided into six layers, but hydrochemical indications were made for each 10 cm section of core. The complete data set was subjected...
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Integrated safety and security analysis of hazardous plants and systems of critical infrastructure
PublicationThis article addresses an integrated safety and security analysis approach of hazardous industrial plants and systems of critical infrastructure. Nowadays due to new hazards that emerge there are opinions among experts that these issues require an integrated approach in life cycle, from the design concept, through the design and operation of the plant, to its decommissioning. It is proposed to start from an interesting methodology...
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Application of gas chromatography to the analysis of spirit-based alcoholic beverages
PublicationSpirit-based beverages are alcoholic drinks, which production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze and scientists commonly choose a gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with a various...
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WYBRANE WŁAŚCIWOŚCI FIZYCZNO-CHEMICZNE MIKROSFER I MOŻLIWOŚĆ ICH WYKORZYSTANIA W KOMPOZYTACH CEMENTOWYCH : The selected physico-chemical properties of microspheres and possibility of their use in cement composites
PublicationMicrospheres are formed during the mineral transformation stage in coal combustion. Their content in fly ashes from the combustion of different types of coals varies over a rather wide range from 0.01 to 4.8 wt.%. The microspheres have three main elements, silicon, aluminum and iron, the oxides of which account for about 89.0 wt.% of the material. Mineralogical analysis using XRD shows that microspheres mainly contain mullite and...
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Physical-chemical processes of diamond grinding
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Chemical Quality of Bottled Waters: A Review
PublicationBottled water has become very popular for quenching thirst and as a dietary (mineral) supplement. Theplethora of natural mineral waters precludes any unequivocal system of classification, which makes it difficult for theconsumer to choose a water with properties that suits him/her exactly. The ever-increasing popularity of bottled watersmeans that it is of the utmost importance to determine not only their mineral content, but above...
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High resolution liquid chromatography and time of flight mass spectrometry in perfume analysis
PublicationPerfumes consist of a wide range of natural and synthetic compounds that belongs to different chemical classes. Most of these compounds are generally determined by GC. However, in this study RP-HPLC-Q-TOF-MS and HILIC-Q-TOF-MS technique was applied for the determination of ingredients of original perfumes and their imitations. Antioxidants and compounds specific to fragrances of animal \origin were found in original...
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Granulometric analysis to etimate influence of anionic surfactrant on activated sludge structure
PublicationThe work concerns the evaluation of the possibility of using laser diffraction analyzer to determine changes in the distribution of sludge floc size in the presence of anionic surfactant. As a model of surfactant linear alkylbenzyne sulphonate (LAS) was used. The granulometric analysis showed that the pure activated sludge was composed of particles with a size of 0,001 to 2 mm. The largest and fastest changes in the distribution...
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Chemical pretreatment of feed water for membrane distillation
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Chemical fingerprint ofPotentillaspecies by using HPTLC method
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POULTRY MANURE AS A SUBSTRATE FOR AGRICULTURE AND THE CHEMICAL INDUSTRY
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A history of the physical and chemical stability of pharmaceuticals : a review
Publication: There is a great need for a broad range review of stability tests of active pharmaceutical ingredients (APIs) in comparison with current requirements contained in the pharmacopoeia. This review focuses on a pharmaceutical history of physical and chemical stability determination. Traditional knowledge must be considered in the context of physical stability, while new knowledge must be applied and acquired in terms of identification...
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Chemical, biological and functional aspects of food lipids
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Review of ionic liquids applications in chemical processes
PublicationCiecze jonowe stały się obiektem zainteresowania naukowców. Składają się one z dużego organicznego kationu i małego anionu. Modyfikacje kationu i anionu pozwalają na dostosowanie ich właściwości do aktualnych potrzeb. Rozpuszczają one szerokie spektrum związków organicznych i nieorganicznych związków. Mogą zatem z powodzeniem zastąpić dotychczas stosowane tradycyjne rozpuszczalniki. Znajdują zastosowanie jako medium reakcyjne,...
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Fluorescence Measurements for chemical optical sensor of cobalt
PublicationW pracy zaproponowano i opisano optoelektroniczny fluorescencyjny sensor do pomiaru stężenia kobaltu w wodzie.
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Selected Methods for the Chemical Phosphorylation and Thiophosphorylation of Phenols
PublicationThis Focus Review gathers together a selection of methods for the chemical phosphorylation of phenols that employ three‐ and four‐coordinate phosphorus compounds. Phosphorylated scaffolds can exhibit enhanced properties compared to their non‐phosphorylated analogues, such as increased biological activity and increased/decreased solubility; as such, phosphorus compounds have gained more and more interest in organic and medicinal...
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Succinite, Baltic Amber: A Chemical Masterpiece of Nature
PublicationSuccinite, Baltic amber, is one of the most appreciated fossil resins. Its beauty has fascinated people since prehistoric times. It is a substance, and also gemstone, whose uniqueness is due to its compelling, though still not fully understood, physicochemical nature. In this article, some facts about the physical and chemical properties of succinite in order to find an answer for questions about the unique properties of this resin,...
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Application of nonlinearity measures to chemical sensor signals
PublicationSzumy rezystancji sensorów gazu zawierają istotną informację, która może być przedstawiona nie tylko przez ich gęstość widmową mocy. Analiza tych szumów za pomocą różnych miar nieliniowości może prowadzić do znacznego wzrostu selektywności i czułości czujników gazu. Stwierdzono, że dla dostępnych na rynku czujników gazu zastosowanie funkcji bispektrum dostarcza dodatkowej informacji, potrzebnej do detekcji różnych gazów. Analizując...
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On the joint time-frequency characteristics of chemical oscillations
PublicationZaprezentowano rezultaty analizy czasowo-częstotliwościowej rejestrów potencjałowych oscylacyjnej reakcji Biełousowa-Żabotyńskiego (BŻ). Wybraną reprezentację czasowo-częstotliwościową w postaci algorytmu STFT zastosowano do analizy typowych przebiegów reakcji BŻ, prowadzonej w układzie zamkniętym. Zaprezentowano spektrogramy STFT ukazujące czasowo-częstotliwościową strukturę oscylacji regularnych, mieszanych i chaotycznych. Na...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublicationThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublicationThe aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology...
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Direct Analysis of Samples of Various Origin and Composition Using Specific Types of Mass Spectrometry
PublicationOne of the major sources of error that occur during chemical analysis utilizing the more conventional and established analytical techniques is the possibility of losing part of the analytes during the sample preparation stage. Unfortunately, this sample preparation stage is required to improve analytical sensitivity and precision. Direct techniques have helped to shorten or even bypass the sample preparation stage; and in this...
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Chemical Composition and Antimicrobial Activity of New Honey Varietals
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Chemical Hand Warmers in Protective Gloves: Design and Usage
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New materials and technologies used in chemical equipment design
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The Influence of Waste Expanded Perlite on Chemical Durability of Mortars
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Ionization of tocopherols and tocotrienols in atmospheric pressure chemical ionization
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Quantum chemical modeling of electrochromism of tungsten oxide films
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Polymerization of chloro-p-xylylenes, quantum-chemical study
PublicationThe p-xylylene monomers of parylene N, C and D have similar high polymerization reactivity. For effective copolymerization processes this fact is basically a draw- back and for instance the copolymerization with styrene doesn't go at all (Corley et al. J Pol Sc 13(68):137156, 1954). Substitution of terminal hydrogen atoms by chlorine atoms reduces reactivity dramatically. 7,7,8,8-tetrachloro-p- xylylene and 2,5,7,7,8,8-hexachloro-p-xylylene...
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Functionalization of Parylene During Its Chemical Vapor Deposition
PublicationTwo possible mechanisms for the reaction of four halogenated (metha)acrylate-based molecules with Parylene [poly (paraxylylene)] during its chemical vapor deposition were proposed. The chemical reactivity of acrylate double bond with the paraxylylene biradical was calculated for all four (metha)acrylate-based molecules. These calculations allowed the evaluation of the energetically favorable mechanism and indeed a direct correlation...