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Wyniki wyszukiwania dla: aqueous organic solvents
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Functionalized nanodiamonds as a perspective green carbo-catalyst for removal of emerging organic pollutants
PublikacjaRapid industrial and urban development jointly with rising global population strongly affect the large-scale issues with drinking, groundwater, and surface water pollution. Concerns are not limited to environmental issues but also human health impact becoming serious global aspect. Organic pollution becomes a primarily serious hazard, therefore, the novel sophisticated approaches to treat them are thoroughly investigated. Among...
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Apparent molar volume and compressinility of tetrabutylphosphonium bromide in various solvents
PublikacjaW oparciu o pomiary gęstości wyznaczono pozorne objętości molowe bromku czero-n-butylofosfoniowego w etanolu, 1-propanolu, 1-butanolu, acetonie i acetonitrylu w przedziale temperatur od 288,15 K do 323,15 K. Ponadto zmierzone w 298,15 K szybkości rozchodzenia się dźwięku w badanych cieczach pozwoliły obliczyć pozorne ściśliwości adiabatyczne bromku. Wielkości pozorne ekstrapolowano do nieskończenie rozcieńczonego stężenia w celu...
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Injection of charge into the archetype organic hole transporting material TPD at the electrical contacts with ITO and Al
PublikacjaW pracy opisano mechanizm przewodnictwa ciemnego w układzie ITO/warstwa TPD/Al oraz Al/warstwa TPD/Al, gdzie TPD oznacza dwaminę powszechne stosowaną jako transporter dziur w organicznych diodach EL.
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublikacjaLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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Oxychlorination of organic compounds
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Organic syntheses greenness assessment with multicriteria decision analysis
PublikacjaGreen chemistry requires a metrics system that is comprehensive by the criteria included and simple in the application at the same time. We propose the application of multicriteria decision analysis for com- parative greenness assessment of organic synthesis procedures. The assessment is based on 9 criteria (the reagent, reaction efficiency, atom economy, temperature, pressure, synthesis time, solvent, catalyst and reactant) for...
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Human hair as a biomarker of human exposure to persistent organic pollutants (POPs)
PublikacjaThe main aim of this article is to investigate the possibility of using human hair as a biomarker with particular emphasis on persistent organic pollutants (POPs). We report previous results of studies of this topic. We critically review the available information on analytical procedures applied during analysis of human hair. Finally, we discuss future trends and possibilities arising from hair analysis.
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Comparison of High Performance Liquid Chromatography Methods with Different Detectors for Determination of Steroid Hormones in Aqueous Matrices
PublikacjaThis paper presents the development and comparison of procedures for the qualitative and quantitative determination of five estrogenic compounds (17-a-ethynylestradiol, estrone, estradiol, estriol, and progesterone) in drinking water and wastewater samples. Five extraction columns and two disks were tested for their efficiency. The C18 columns were superior on the basis of cost for solid phase extraction of drinking water or sewage....
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Molecularly imprinted polymers based on deep eutectic solvents as a greenest materials for selective extraction of emerging contaminants from complex samples
PublikacjaSome of the reagents applied in the synthesis of molecularly imprinted polymers (MIPs) may impact on health and the environment. Thus, a new generation of promising green chemicals are nowadays introduced and investigated, including deep eutectic solvents (DESs). DESs seems to be a reasonable choice as they are characterized as non-toxic, low cost, easy to prepare and biodegradable chemicals. This review presents the information...
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Four-body recombination in organic bulk heterojunction solar cells: an alternative interpretation
PublikacjaWe demonstrate a new interpretation of the previously reported quadrimolecular recombination in organic bulk heterojunction solar cells. It is suggested that the recently described (Szmytkowski 2012 Phys. Status Solidi RRL 6 300) interaction between exciton and electron–hole Langevin bound pair formed across the donor–acceptor interface is a four-particle process. This is in opposition to the treatment of this effect as a three-particle...
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Influence of excitons interaction with charge carriers on photovoltaic parameters in organic solar cells
PublikacjaWe report on theoretical analysis of excitons annihilation on charge carriers in organic solar cells. Numerical calculations based on transient one-dimensional drift-diffusion model have been carried out. An impact of three quantities (an annihilation rate constant, an exciton mobility and a recombination reduction factor) on current density and concentrations of charge carriers and excitons is investigated. Finally, we discuss...
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Determination of the chemical structure of potencial organic impurities occuring in the drug substance opopramol
PublikacjaThe tricyclic antipsychotic and antidepressant drug opipramol was examined with regard to the chemical structure of its organic impurities. Impurities were isolated from the technical product by chromatographic methods and their chemical structures were estabilished by HMNR, MS and FTIR.
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Use of electrochemical methods to examine different surface preparation methods for organic coatings on steel
PublikacjaObróbka strumieniowo - ścierna jest jedną z powszechnie stosowanych metod przygotowania powierzchni. Wśród nowoczesnych metod coraz większe zainteresowanie wzbudza przygotowanie powierzchni wodą pod wysokim ciśnieniem (z ang. waterjetting). W porównaniu z konwencjonalnymi metodami ''waterjetting'' jest nowoczesną oraz przyjazną środowisku metodą. W literaturze brakuje informacji na temat skuteczności owej metody do zastosowań...
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Synthetic strategies in construction of organic low molecular-weight carrier-drug conjugates
PublikacjaInefficient transportation of polar metabolic inhibitors through cell membranes of eukaryotic and prokaryotic cells precludes their direct use as drug candidates in chemotherapy. One of the possible solutions to this problem is application of the ‘Trojan horse’ strategy, i.e. conjugation of an active substance with a molecular carrier of organic or inorganic nature, facilitating membrane penetration. In this work, the synthetic...
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The hydration properties of protein stabilizer, trimethylamine-N-oxide in aqueous solutions of N-methylacetamide – The volumetric and compressibility studies between 288.15 and 308.15 K
PublikacjaApparent molar volumes and apparent molar isentropic compressions of the protein stabilizer, trimethylamine-N-oxide (TMAO) were determined from the densities and speed of sound measured at T = (288.15, 298.15 and 308.15) K in aqueous solutions of N-methylacetamide (NMA) at four different concentrations (2, 4, 6 and 8 mol/kg). The concentration dependencies of the calculated quantities extrapolated to the infinite dilution lead...
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The influence of the thickness, recombination and space charge on the loss of photocurrent in organic semiconductors: an analytical model
PublikacjaWe propose an analytical model of the photocurrent efficiency dependence on the light intensity in organic semiconductors. The influence of the thickness of sample, space charge effects and recombination of charge on the loss of photocurrent has been considered. We demonstrate that the presented model is the enhancement of an analytical model reported recently by Rappaport et al (2005 J. Appl. Phys. 98 033714). The method to identify...
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Measurements of Activity Coefficients at Infinite Dilution for Organic Solutes in the Ionic Liquids N-Ethyl- and N-Octyl-N-methylmorpholinium Bis(trifluoromethanesulfonyl)imide. A Useful Tool for Solvent Selection
PublikacjaIn recent years, many papers describing ionic liquids (IL) as promising solvents in separation techniques have been published. The conscious choice of appropriate ionic liquid as absorption media in effective extraction of selected types of analytes requires deeper understanding of the analyte−IL interactions. Therefore, intensive research is conducted to determine the values of activity coefficient at infinite dilution, which...
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Interactions of Chromium Ions with Starch Granules in an Aqueous Environment
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Thermodynamics of micellization of imidazolium ionic liquids in aqueous solutions
PublikacjaPodobieństwo pomiędzy strukturami niektórych cieczy jonowych, a surfaktamtami jonowymi wskazuje na możliwość wykazywania, przez te związki, tendencji do agregacji i adsorpcji na powierzchniach międzyfazowych. Mierząc w różnych temperaturach przewodnictwo elektryczne w funkcji stężenia oznaczono temperaturę Kraffta i zależność temperaturową krytycznego stężenia micelizacji (CMC) dla czterech, różniących się długościami łańcucha,...
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Hydration of Carboxylate Anions: Infrared Spectroscopy of Aqueous Solutions
PublikacjaHydratacja anionów karboksylanowych w roztworach wodnych ich soli sodowych została zbadana przy wykorzystaniu spektroskopii FTIR z zastosowaniem cząsteczki HDO jako sondy molekularnej. Do wyznaczenia widm wody zaburzonej przez rozpuszczalnik wykorzystano ilościową wersję metody widm różnicowych. Widma te wykazują dwa pasma składowe przy ok. 2550 i ok. 2420 cm-1. Pasma te przypisano grupie -COO- anionu R-COO- (R = H, CH3, C2H5),...
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Micelle formation of imidazolium ionic liquids in aqueous solution
PublikacjaCiecze jonowe (ILs) stanowią nową klasę związków o szerokich możliwościach przemysłowego zastosowania. Z przeglądu dostępnej literatury wynika, że niektóre ciecze jonowe tworzą agregaty w roztworach wodnych. W celu określenia jak tworzenie agregatów może wpływać na przebieg procesów technologicznych, dystrybucję w środowisku oraz toksyczność konieczne jest przeprowadzenie systematycznych badań dotyczących właściwości powierzchniowych...
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Self-organization of imidazolium ionic liquids in aqueous solution
PublikacjaW pracy przeanalizowano i podsumowano wyniki badań nad samoorganizacją oraz tworzeniem micel cieczy jonowych w roztworach wodnych otrzymane przez wiele zespołów badawczych. Średnio i długołańcuchowe imidazoliowe ciecze jonowe wykazują aktywność powierzchniową zależną od długości łańcucha alkilowego w kationie, analogicznie do kationowych surfaktantów. Wskazano na liczne zagadnienia, które wymagają dalszych systematycznych badań
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Aggregate formation of imidazolium ionic liquids in aqueous solution
PublikacjaCiecze jonowe (ILs) stanowią nową klasę związków o szerokich możliwościach przemysłowego zastosowania. Z przeglądu dostępnej literatury wynika, że niektóre ciecze jonowe tworzą agregaty w roztworach wodnych. Zrozumienie oddziaływań międzycząsteczkowych cieczy jonowych w środowisku wodnym jest niezbędne dla prawidłowego projektowania, przewidywania i kontroli ich właściwości jako współ-rozpuszczalników, a w konsekwencji procesów...
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Hard anodization of copper in potassium carbonate aqueous solution
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Photodegradation and advanced oxidation of endocrine disruptors in aqueous solutions
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Adsorption of CCl4 from Aqueous Solution on Activated Carbons
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Modified acrylamide copolymers as flocculants for model aqueous suspensions
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Non-aqueous Fracturing Technologies for Shale Gas Recovery
PublikacjaTechnologie szczelinowania wykorzystywane podczas wydobycia gazu z łupków zostały rozwinięte głównie w USA i są obecnie przystosowywane do warunków geologicznych i wymagań ekologicznych w innych państwach. Praca przedstawia literaturę na temat teoretycznych i praktycznych aspektów wydobycia gazu z łupków z naciskiem na technologie alternatywne do szczelinowania hydraulicznego. Rozpatrzono również techniczne i środowiskowe aspekty...
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Theoretical pKa prediction of O-phosphoserine in aqueous solution
PublikacjaSprawdzono zdolność modelu polaryzowalnego kontinuum (PCM) do przewidywania wartości pKa w roztworze wodnym dla O-fosfoseryny (P-Ser). Obliczenia przeprowadzono w ramach teorii funkcjonału gęstości (DFT) przy użyciu funkcjonałów B3LYP i M06-2X oraz baz 6-31+G(d) and 6-31+G(d,p). Obliczenia na poziomie B3LYP/6-31+G(d,p) przy użyciu modelu solwatacji SMD zapewniają doskonałą zgodność z doświadczeniem, pod warunkiem uwzględnienia...
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Hydration of Simple Model Peptides in Aqueous Osmolyte Solutions
PublikacjaThe biology and chemistry of proteins and peptides are inextricably linked with water as the solvent. The reason for the high stability of some proteins or uncontrolled aggregation of others may be hidden in the properties of their hydration water. In this study, we investigated the effect of stabilizing osmolyte–TMAO (trimethylamine N-oxide) and destabilizing osmolyte–urea on hydration shells of two short peptides, NAGMA (N-acetyl-glycine-methylamide)...
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Analysis of higher recombination orders in organic bulk heterojunction solar cells
PublikacjaRecently, it has been experimentally demonstrated that an order of nongeminate recombination exceeds two in some types of organic bulk heterojunction donor-acceptor structures. This result is different than for the case of bimolecular recombination described by Langevin theory. Although several theoretical explanations of this effect have been presented, the origin of higher recombination orders is still questionable. In this work,...
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Structural changes of a simple peptide—Trpzip-1—in aqueous solutions and the corresponding hydration phenomena under the influence of temperature
PublikacjaTrpzip-1, a simple β-hairpin, is a rare example of peptide with stable secondary structure and can be a convenient model to study temperature-related processes that potential prion or amyloid proteins undergo. Although its sequence is simple, the exact processes which the peptide undergoes in aqueous solutions are quite complex and not well understood. The selection of well-established experimental (DSC, FTIR) and theoretical methods...
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Solubility of Carbon Dioxide in Deep Eutectic Solvents Based on 3-Amino-1-Propanol and Tetraalkylammonium Salts at Low Pressure
PublikacjaDeep eutectic solvents (DESs) became an object of a great interest as an alternative to ionic liquids (ILs) and commonly used in CO2 capture amine solutions. In the present study, five different DESs based on 3-amino-1-propanol as physical-chemical CO2 absorbents were used. The composition was chosen in order to estimate the effects of hydrogen bond acceptor:hydrogen bond donor (HBA:HBD) molar ratio, anion type and length of alkyl...
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High order of nongeminate recombination in organic bulk heterojunction solar cells
PublikacjaWe analyze high order of nongeminate recombination in organic donor–acceptor bulk heterojunction solar cells. The model of recombination where an exciton annihilates on an electron–hole Langevin bound pair near donor–acceptor interface has been applied in our studies. We obtained satisfactory agreement between experimental results and theoretical calculations for the concentration dependences of several parameters characterizing...
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Non-regulated organic compounds (NROC's) in the Odra River water samples.
PublikacjaW ramach badań opisanych w pracy podjęto próbę identyfikacji lotnych i średniolotnych związków z grupy Non-Regulated Organic Compounds obecnych w próbkach wody rzecznej. Analizie poddano 25 próbek wód pobranych z rzeki Odry w październiku 2000, w trakcie VIII kampanii zorganizowanej w ramach International Odra Project (IOP). W badaniach wykorzystano technikę PT-TD-GC-MS.Komputerowa analiza widm masowych wykazała obecność wielu...
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Friction-Induced Oscillations of a Non-Asbestos Organic Pin Sliding on a Steel Disc
PublikacjaFriction-induced oscillations result in deterioration of performance of disc brakes and are generally undesired. We conduct experimental study of friction-induced oscillations in a non-asbestos organic material / steel pair used in disc brakes of motor vehicles. The tests are done by use of a pin-on-disc machine which has the pin sample supported on a deformable beam. The adjustable friction parameters are the disc velocity, contact...
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Miniaturized Passive Emission Chambers for In Situ Measurement of Emissions of Volatile Organic Compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air. The presence of dangerous chemical compounds in indoor air can have an adverse impact on human health and cause numerous diseases of the respiratory and circulatory systems. Such harmful chemicals get into indoor air as a result of their emission from building and indoor materials....
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Modification of current-voltage characteristics of planar organic systems by nm-thick interlayer
PublikacjaEffect of nm-thick interlayer of copper phthalocyanine (CuPc) or perylene dye (MePTCDI) on current-voltage characteristics of planar organic systems is discussed in the work. The MePTCDI layer strongly limits injection of holes from ITO into CuPc, while CuPc limits injection of electrons from ITO into MePTCDI. In the systems with CuPc/MePTCDI heterojunction an explicit photovoltaic effect occurs.
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Recent developments in the determination of residual solvents in pharmaceutical products by microextraction methods
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Usefulness of the Free Length Theory for assessment of the self-association of the pure solvents
PublikacjaWykonano pomiary szybkości rozchodzenia się dźwięku i gęstości metanolu, acetonitrylu, N,N-dimetyloformamidu, N,N-dimetyloacetamidu, dimetylosulfotlenku i fosforanu trietylu w zakresie temperatur 294 - 333 K . W oparciu o wyznaczone ściśliwości adiabatyczne zastosowano teorię FLT do oceny wzajemnej asocjacji cząsteczek. Uzyskane wyniki przedyskutowano na tle innych sposobów klasyfikacji rozpuszczalników.
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Fluctuation-Enhanced Sensing of Organic Vapors by Ink-Printed MoS2 Devices under UV Irradiation
PublikacjaThis work presents the results of fluctuationenhanced sensing (FES) of selected organic gases by MoS2 sensor fabricated via a simple ink printing method. We demonstrate that low-frequency noise measured under UV irradiation (275 nm) is more sensitive to different gases than measured in the dark. The noise at 1 Hz under UV light increased 3.3, 3.5, 1.6, and 2.9 times for chloroform, tetrahydrofuran, acetonitrile, and acetone ambiances, respectively....
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An Aqueous Exfoliation of WO3 as a Route for Counterions Fabrication—Improved Photocatalytic and Capacitive Properties of Polyaniline/WO3Composite
PublikacjaIn this paper, we demonstrate a novel, electrochemical route of polyaniline/tungsten oxide (PANI)/WO3) film preparation. Polyaniline composite film was electrodeposited on the FTO (fluorine-doped tin oxide) substrate from the aqueous electrolyte that contained aniline (monomer) and exfoliated WO3 as a source of counter ions. The chemical nature of WO3 incorporated in the polyaniline matrix was investigated using X-ray photoelectron...
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Development and validation of an eco-compatible UV–Vis spectrophotometric method for the determination of Cu2+ in aqueous matrices
PublikacjaCu 2+ are ubiquitous ions in the ecosystem and are responsible of serious environmental pollution. Indeed, the development of sensitive methods for Cu 2+ detection is an urgent demand. In this work, we proposed a new spectrophotometric method for Cu 2+ determination in different water matrices (distilled water, drinking water, wastewater, and river water). The method employs a bio-based organic ligand namely tetrasodium iminodisuccinate...
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PARTICLE SIZE ANALYSIS OF SUSPENSIONS IN REMOVING OF ORGANIC MATTER AND PHOSPHORUS FROM WASTEWATER AND SURFACE WATER
PublikacjaIn this paper the particle size of suspended solids in the removing of organic matter and phosphorus compounds from lake water and wastewater treated in the Ecological Treatment Systems (ETS) was analyzed. The invesigated materials were taken from two ETS located in Pomerania Region/Poland. Object in Swarzewo is 3rd stage of biological treatment of municipal wastewater, while object in Kartuzy has task to remove a phosphorus from...
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Monitoring and analytics of semivolatile organic compounds (SVOCs) in indoor air
PublikacjaThis paper reviews literature information on the behaviour of semivolatile organic compounds (SVOCs) in the indoor environment, as well as the most likely emission sources. The consecutive stages of analytical procedures used for monitoring SVOCs in indoor environments are described. The most common approaches used for collecting samples from the gas and particulate phases are mentioned. The paper discusses and compares various...
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Properties and Formation of Mineralized Veins in an Organic-Rich Shale Formation
PublikacjaAn earlier paper defined mineral and organic matter constituents in weak interfaces in shale formations (Ptaszynska, et. al., 2016). The formation studied in the earlier work and here is the Jurassic, early-Cretaceous Vaca Muerta formation in the Neuquen basin in Argentina. In this earlier work, mineralized "veins" were noted to be prevalent and complicated, sometimes being shear weak interfaces while in other cases they were not....
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Miniaturized passive emission test chamber for in-situ measurement of emissions of organic compounds
PublikacjaThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air (outdoor). One of the main groups of chemical compounds present in indoor air, with proven harmfulness to health,are volatile organic compounds (VOCs). VOCs present indoor comprise a wide variety of hydrocarbons and hydrocarbons derivatives including aliphatic, aromatics, alkylbenzens,...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part II. Sample collection and preparation
PublikacjaThe paper reviews literature information on air sampling techniques commonly used for monitoring volatile organic compounds (VOCs) levels in atmospheric air. It describes containers for collecting samples of atmospheric air, such as vacuum canisters and bags made from synthetic materials. It discusses dynamic, passive and denudational techniques for sampling analytes from air combining isolation with preliminary enrichment, and...
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Electrode materials for electrochemical capacitors based on poly(3,4-ethylenedioxythiophene) and functionalized multi-walled carbon nanotubes characterized in aqueous and aprotic electrolytes
PublikacjaWithin this work, we report a facile one-stage synthesis of nanocomposites based on functionalized carbon nanotubes (CNTs) and electroactive polymer poly(3,4-ethylenedioxythiophene). Three different composites are investigated as potential electrode materials for the electrochemical capacitors. Two of the composites contain carbon nanotubes (ox-CNTs), functionalized by acid oxidation process (65% HNO3, 120 °C). The third composite...
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Organic Rankine cycle as bottoming cycle to a combined Brayton and Clausius - Rankine cycle
PublikacjaA preliminary evaluation has been made of a possibility of bottoming of a conventional Brayton cycle cooperating with the CHP power plant with the organic Rankine cycle installation. Such solution contributes to the possibility of annual operation of that power plant, except of operation only in periods when there is a demand for the heat. Additional benefit would be the fact that an optimized backpressure steam cycle has the advantage...