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Search results for: aqueous organic solvents
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Removal of organic matter and nitrogen in an horizontalsubsurface flow (HSSF) constructed wetland undertransient loads
PublicationA monitoring campaign in a horizontal subsurface flow constructed wetland under the influence of transient loads of flow-rate, organic matter, nitrogen and suspended solids showed an irregular removal of COD and TSS and lower both removal efficiencies and mass removal rates than the ones observed in other studies for similar operating conditions. This circumstance is associated to the presence of large amount of particulate organic...
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Modeling of Transient Photocurrent in Organic Semiconductors Incorporating the Annihilation of Excitons on Charge Carriers
PublicationThe role of the annihilation of excitons on charge carriers has been theoretically investigated in organic semiconductors. We have developed the numerical drift-diffusion model by incorporation terms which describe the annihilation process. The transient photocurrent has been calculated for different injection barrier heights, exciton mobilities, and annihilation rate constants. We have demonstrated that the annihilation has a...
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Determination of the chemical structure of potential organic impurities occurring in drug substance opipramol
PublicationThe tricyclic antipsychotic and antidepressant drug opipramol (opipramole) 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 established by 1H NMR, MS and FTIR and further confirmed by comparison with commercially available products or with products obtained by independent synthesis, and...
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Enabling simultaneous redox transformation of toxic chromium(VI) and arsenic(III) in aqueous media—A review
PublicationSimultaneous conversion of most harmful As(III) and Cr(VI) to their less toxic counterparts is environmentally desirable and cost-effective. It has been confirmed that simultaneous oxidation of As(III) to As(V) and reduction of Cr(VI) to Cr(III) can occur via free radical or mediated electron transfer processes. While Cr(VI) is reduced by reacting with H•, eaq−, photoelectron directly or undergoing ligand exchange with H2O2 and...
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Coordination complexes of Mn(II), Co(II), Ni(II), Zn(II) and Cd(II) with histaminol – Crystal structures and formation constants in aqueous solution
PublicationStability constants were determined for a series of coordination complexes of Mn(II), Co(II), Ni(II), Zn(II) and Cd(II) with histaminol in aqueous solution. The tendency of histaminol to form chelate complexes has been confirmed by the isolation of several complex species in the monocrystalline form and determination of their molecular structures.
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Analytical techniques for trace organic compounds-III: Mass spectrometry in trace organic analysis
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Corncob-supported calcium oxide nanoparticles from hen eggshells for cadmium (Cd-II) removal from aqueous solutions; Synthesis and characterization
PublicationThis study investigated the efficient removal of cadmium ions from aqueous solutions using calcium oxide nanoparticles (CaO NPs) synthesized from waste hen eggshells using a Sol-gel method and supported on corncob bio-adsorbent. The synthesized CaO NPs were characterized using FT-IR, XRD, specific surface area, and TGA. Batch adsorption experiments were conducted to examine the influence of process parameters such as adsorbent...
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Solvothermal synthesis and structural characterization of three polyoxotitanium-organic acid clusters
PublicationThree new titanium oxo-clusters Ti4O2(OiPr)10(OOCPhMe)2 (I), Ti6O4(OEt)8(OOCPhMe)8 (II) and Ti6O6(OEt)6(OOCCHPh2)6 (III) were obtained by easy one-step solvothermal reactions of titanium(IV) isopropoxide, alcohols and carboxylic acids. The three compounds were characterized by single-crystal and powder X-ray diffraction, TGA/DSC, optical and electron microscopy, and FTIR and NMR spectroscopy. X-ray powder diffraction and spectroscopy...
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Nutritional and Pharmaceutical Properties of Bioactive Compounds in Organic and Conventional Growing Kiwifruit
PublicationThe bioactivity of two kiwifruit’s cultivars growing under organic and conventional conditions were studied and compared. The bioactive compounds were extracted with water and ethanol using similar conditions which are applied in pharmaceutical applications and for daily fruit consumption such as tea drink. Antioxidant radical scavenging assays [ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC);...
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Comparative study of selected fluids for use in supercritical Organic Ranking Cycles
PublicationIn view of increasing interest in improving energy efficiency of energy conversion devices, there is an increasing requirement of combined production of heat and electricity as well as demand for increased implementation of renewable energy resources. The micro cogenerative units utilizing the Organic Rankine Cycle are focusing the attention of many research centres around the world. In the present paper calculations of ORC cycles...
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Structural, mechanical and thermal behavior assessments of PCL/PHB blends reactively compatibilized with organic peroxides
PublicationThe efficiency of two commercially available organic peroxides, dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB), during reactive processing of poly (ε-caprolactone)/poly (3-hydroxybutyrate) (PCL/PHB) blends was investigated. The changes in chemical structure of PCL/PHB blends, as a function of organic peroxide type (DCP/BIB) and content (in range: 0–1.0 parts by weight - pbw), were characterized by Fourier...
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Organic carbon fluxes of a glacier surface: a case study of Foxfonna, a small Arctic glacier
PublicationArctic glaciers are rapidly responding to global warming by releasing organic carbon (OC) to downstream ecosystems. The glacier surface is arguably the most biologically active and biodiverse glacial habitat and therefore the site of important OC transformation and storage, although rates and magnitudes are poorly constrained. In this paper, we present measurements of OC fluxes associated with atmospheric deposition, ice melt,...
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Characteristics and fate of organic nitrogen in municipal biological nutrient removal wastewater treatment plants
PublicationThe aim of this study was to investigate the occurrence and fate of colloidal and dissolved organic nitrogen (CON and DON) across biological nutrient removal (BNR) activated sludge bioreactors. Primary and secondary effluent total nitrogen (TN) measurements and component fractionation, CON and DON concentration profiles across BNR bioreactors, and laboratory batch experiments with the process mixed liquor were carried out at several...
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Green sample preparation techniques for chromatographic determination of small organic compounds
PublicationAccurate monitoring of the state of the environment requires the introduction of additional isolation and/or preconcentration step prior to the chromatographic determination. In this work the information about novel methodological and instrumental solutions in relation to different variants of microextraction techniques are presented. Attention is focused on analytical procedure and suitable analytical tools for extraction of the...
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Application of organic materials in electronics
PublicationRozwój urządzeń elektronicznych na bazie materiałów organicznych przestawia jedno z najbardziej spektakularnych osiągnięć nauki w XXI wieku. Do produkcji zostały wdrożone urządzenia zbudowane na cienkich warstwach organicznych, i poczynione zostały pierwsze kroki w kierunku rozwoju elektroniki molekularnej. Celem publikacji jest dostarczenie podstawowych informacji dotyczących urządzeń elektronicznych zbudowanych na bazie cienkich...
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Organic light emitting devices
PublicationW pracy przedstawiono podstawowe procesy fizyczne zachodzące w organicznych emiterach elektroluminescencyjnych oraz parametry techniczne tego typu układów.
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Applications of Alkanethiols in Organic Synthesis
PublicationThis manuscript is an update to the earlier Science of Synthesis contribution describing methods for the synthesis of alkanethiols. Thiols can be converted into sulfonic, sulfinic, sulfenic acid and their derivatives, sulfides, disulfides, polysulfides, sulfonium salts, and thiiranes, etc. These transformations are accomplished by nucleophilic displacement or addition, oxidation, condensation, or coupling reactions involving thiol...
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On organic coatings in marine applications
PublicationZnaczna liczba konstrukcji eksploatowanych w warunkach morskich ulega zniszczeniu wskutek zmęczeniowego oddziaływania cyklicznych naprężeń mechanicznych. Również w przypadku powłok organicznych chroniących wspomniane konstrukcje obserwuje się przedwczesną degradację zmęczeniową. W poniższym artykule autorzy przedstawiają metodologię oceny wpływu cyklicznych naprężeń mechanicznych na trwałość ochronnych układów powłokowych. Badaniu...
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Organic compounds in indoor environments
PublicationPraca jest przeglądem literaturowym dotyczącym obecności lotnych związków organicznych w powietrzu wewnętrznym. Zaprezentowano główne źródła zanieczyszczeń powietrza wewnętrznego, poruszono tematykę sumarycznej zawartości LZO oraz wpływu zanieczyszczeń powietrza atmosferycznego na jakość powietrza wewnętrznego.
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Testing and sampling devices for monitoring volatile and semi-volatile organic compounds in indoor air
PublicationAdults spend most of their time in enclosed spaces (e.g., apartment, office and public buildings). According to research conducted by scientists, air quality indoors is much worse than the ambient air quality outdoors. Hazardous chemicals found in air indoors can adversely affect the functioning of the human body and cause many respiratory and circulatory diseases. Harmful chemical compounds (mainly volatile organic compounds and...
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Thermal Instability of Choline Chloride-Based Deep Eutectic Solvents and Its Influence on Their Toxicity─Important Limitations of DESs as Sustainable Materials
PublicationDeep eutectic solvents (DESs) have become a hot topic in many branches of science due to their remarkable properties. They have been studied in a wide variety of applications. In particular, choline chloride (ChCl)-based DESs are one of the most commonly used representatives of these fluids. Nevertheless, in order to apply DESs in some fields, it is essential to guarantee their stability, reusability, and biocompatibility. In this...
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Generalized Einstein relation in disordered organic semiconductors: Influence of the acoustic phonons–charge carriers scattering
PublicationIn this work, we analyze the generalized Einstein relation for disordered organic semiconductors with a non-equilibrium Druyvesteyn-type distribution function. The Druyvesteyn behavior of hot electrons in a solid state is associated with the acoustic phonons–charge carriers scattering. Such a case has been experimentally demonstrated in electroluminescent inorganic rare–earth–doped zinc chalcogenides. Therefore, we can assume that,...
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Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane–SPME
PublicationCommercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane–solid-phase...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublicationThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Experimental and Machine-Learning-Assisted Design of Pharmaceutically Acceptable Deep Eutectic Solvents for the Solubility Improvement of Non-Selective COX Inhibitors Ibuprofen and Ketoprofen
PublicationDeep eutectic solvents (DESs) are commonly used in pharmaceutical applications as excellent solubilizers of active substances. This study investigated the tuning of ibuprofen and ketoprofen solubility utilizing DESs containing choline chloride or betaine as hydrogen bond acceptors and various polyols (ethylene glycol, diethylene glycol, triethylene glycol, glycerol, 1,2-propanediol, 1,3-butanediol) as hydrogen bond donors. Experimental...
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Experimental and Machine-Learning-Assisted Design of Pharmaceutically Acceptable Deep Eutectic Solvents for the Solubility Improvement of Non-Selective COX Inhibitors Ibuprofen and Ketoprofen
PublicationDeep eutectic solvents (DESs) are commonly used in pharmaceutical applications as excellent solubilizers of active substances. This study investigated the tuning of ibuprofen and ketoprofen solubility utilizing DESs containing choline chloride or betaine as hydrogen bond acceptors and various polyols (ethylene glycol, diethylene glycol, triethylene glycol, glycerol, 1,2-propanediol, 1,3-butanediol) as hydrogen bond donors. Experimental...
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Prototype of electrochemical sensor for measurements of volatile organic compounds in gases
PublicationThe paper presents a laboratory prototype of an electrochemical sensor for measurements of volatile organic compounds (VOCs) in gases, utilizing ionic liquids and commercial screen printed electrodes by DropSens. The following ionic liquids have been tested as the electrolyte and redox reaction environment: 1-butyl, 3-methylimidazolium dicyanoamide ([BMIM][N(CN)2]), 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM][BF4]),...
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The use of fungi in biofiltration to remove hydrophobic volatile organic compounds
PublicationThe growing importance placed on air quality by environmental regulations and public opinion necessitate the minimization and removal of volatile organic compound emissions (VOCs), including odours. The removal of hydrophobic VOCs from the air by biological methods remains a major technical challenge (despite its importance in the shift to green engineering). A potential solution to this challenge is the use of fungi in biofiltration....
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Analytical method for calculation of heat source temperature drop for the Organic Rankine Cycle application
PublicationIn the paper presented are considerations on the cooperation of the limited capacity heat source with the Organic Rankine Cycle unit. Usually the heat source providing thermal energy to the Organic Rankine Cycle (ORC) may have twofold characteristics. It can be in the form of a single phase fluid, i.e. as hot exhaust gas or hot liquid, or in some cases it may be available as a phase changing fluid, as for example, technological...
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Particle size analysis of suspensions in removing of organic matter and phosphorus from waste water and surface water
PublicationIn this paper the particle size of suspended solids in the removing of organic matter and phosphorus compounds from lake- and waste- water 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 waste water, while object in Kartuzy has task to remove a phosphorus from...
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Singlet oxygen-dominated peroxymonosulfate activation by layered crednerite for organic pollutants degradation in high salinity wastewater
PublicationAdvanced oxidation processes have been widely studied for organic pollutants treatment in water, but the degradation performance of radical-dominated pathway was severely inhibited by the side reactions between the anions and radicals, especially in high salinity conditions. Here, a singlet oxygen (1O2)-dominated non-radical process was developed for organic pollutants degradation in high salinity wastewater, with layered crednerite...
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Ciprofloxacin removal from aqueous solutions by ozonation with calcium peroxide
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Proton hydration in aqueous solution: FTIR studies of HDO spectra
PublicationW artykule scharakteryzowano sfery hydratacyjne protonu w roztworze wodnym na podstawie pomiarów widm FTIR wody półciężkiej (HDO), rozcieńczonej izotopowo w H2O. Wyniki eksperymentalne skonfrontowano z obliczonymi metodami chemii kwantowej strukturami niewielkich klasterów wodnych typu H+(H2O)n. Otrzymane geometrie optymalne porównano z odległościami międzyatomowymi otrzymanymi na podstawie położeń pasm HDO. Pierwsza sfera hydratacyjna...
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Effect of Starch Phosphorylation on Interaction With Chromium Ions in Aqueous Solutions
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Flavin mononucleotide fluorescence intensity decay in concentrated aqueous solutions
PublicationCzasowo-rozdzielone widma absorpcji i fluorescencji FMN w roztworach wodnych zostały zmierzone dla szerokiego zakresu stężeń. Pokazano, że zaniki fluorescencji są silnie przyśpieszone przez obecność dimerów FMN, które stanowią niedoskonałe pułapki energii wzbudzenia. Wyniki doświadczalne porównano z rezultatami symulacji Monte-Carlo, uwzględniającej powrotny transfer energii od pułapek do donorów, stwierdzając dobrą zgodność modelu...
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Zinc Removal from the Aqueous Solutions by the Chemically Modified Biosorbents
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Computational studies of intermolecular interactions in aqueous solutions of poly(vinylmethylether)
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Formation of aqueous and alcoholic adducts of curcumin during its extraction
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DMSO and TMAO—Differences in Interactions in Aqueous Solutions of the K-Peptide
PublicationInteractions between a solvent and their co-solute molecules in solutions of peptides are crucial for their stability and structure. The K-peptide is a synthetic fragment of a larger hen egg white lysozyme protein that is believed to be able to aggregate into amyloid structures. In this study, a complex experimental and theoretical approach is applied to study systems comprising the peptide, water, and two co-solutes: trimethylamide...
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Raman spectroscopic study of Ni2+-DNA interactions in aqueous systems
PublicationMetodą ramanowskich widm różnicowych określono sposób oddziaływania jonu Ni2+ z DNA(CT) w układach wodnych. Kation Ni(II) koordynuje w pozycjach N7 guaniny (G) i adeniny (A) w powtarzających się sekwencjach GG, AA i GA cząsteczki DNA. Jednocześnie Ni2+ oddziałuje zewnątrz sferowo poprzez cząsteczki wody z grupami fosforanowymi DNA.
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Organic Rankine as bottoming cycle to a combined Brayton and Clausius-Rankine cycle
PublicationThis paper presents an enhanced approach, as it will be considered here that the ORC installation could be extra-heated with the bleed steam, a concept presented by the authors. In such way the efficiency of the bottoming cycle can be increased and an amount of electricity generated increases. A thermodynamic analysis and a comparative study of the cycle efficiency for a simplified steam cycle cooperating with ORC cycle will be...
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Metrological parameters of sulphur dioxide amperometric sensor containing addition of aprotic solvents
PublicationW publikacji zaprezentowano wyniki badań nad dodatku rozpuszczalnika aprotycznego do roztworu elektrolitu wewnętrznego czujnika na parametry metrologiczne prototypowego czujnika ditlenku siarki z membraną nafionową. Porównywano właściwości pięciu czujników różniących się składem elektrolitu. W każdym przypadku elektroda pracująca wykonana była ze złota, próżniowo napylonego na powierzchnię membrany. Roztwory elektrolitów zawierały...
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Evaluation of starch plasticization efficiency by deep eutectic solvents based on choline chloride
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Possible application of new class of solvents in the purification of water used in hydraulic fracturing
PublicationNowym źródłem energii niekonwencjonalnej w Polsce może być gaz, który jest uwięziony w łupkach. Podczas poszukiwań gazu łupkowego, duże ilości wody wykorzystywanej w procesie szczelinowania hydraulicznego powracają na powierzchnię zanieczyszczone. Istnieje wiele metod usuwania śladowych ilości węglowodorów tj. fizyczne czyli filtracja czy chemiczne czyli zakwaszanie, ale mogą one być nieskuteczne. Pożądana metoda to monitorowanie...
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Theoretical Organic Rankine Cycle efficiency depending on different thermodynamic work variables.
PublicationOne of promising technologies of utilizing low- temperature waste heat is through ORC (Organic Rankine Cycle) system implementation. A primary objective in designing in-stallations based on such systems is to maximize the installation's work efficiency. On the other hand, ecological factors are commonly considered a natural barrier in introducing new, often very expensive technologies. Ecological effect of a potential modernization...
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Fractionation and origin of dissolved and colloidal organic nitrogen in BNR plant effluent
PublicationThe characteristics of effluent dissolved and colloidal organic nitrogen (DON and CON) as well as their origin, fate and biodegradability in wastewater treatment plants and receiving waters were identified as the major issues that limit the ability to achieve low total N in the effluent. This study presents the results of a comprehensive survey, which was conducted in eight biological nutrient removal (BNR) WWTPs in northern Poland....
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Nongeminate recombination in organic bulk heterojunction solar cells: Contribution of exciton–polaron interaction
PublicationA new model to explain nongeminate recombination in organic bulk heterojunction solar cells is presented. We suggest that the annihilation of excitons on charge carriers at the interface between donor and acceptor phases competes with the bimolecular recombination of Coulombically bound electron–hole pairs. The exciton–polaron interaction gives visible contribution to the reduction of Langevin recombination. An analytical formula,...
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Titanium lanthanum three oxides decorated magnetic graphene oxide for adsorption of lead ions from aqueous media
PublicationThe current study presents a viable and straightforward method for synthesizing titanium lanthanum three oxide nanoparticles (TiLa) and their decoration onto the ferrous graphene oxide sheets to produce FeGO-TiLa as efficient magnetic adsorbent. Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and vibration sample magnetometer (VSM) were used to evaluate...
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Parasites of the digestive tract of sheep and goats from organic farms in Western Pomerania, Poland
PublicationThe aim of the study was to determine the prevalence and intensity of parasite infection of the digestive tract in sheep and goats from the West Pomerania region following anti-parasite treatment. Feces were freely collected from sheep and goats kept on organic farms and subjected to analysis by the Willis-Schlaf and McMaster’s flotation methods. The mean extensity of infection by gastrointestinal parasites...
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New empirical correlations for the viscosity of selected organic phase change materials
PublicationAlthough there are many methods and instruments for measuring viscosity, it is still difficult to determine a reliable value of the dynamic viscosity of complex chemicals such as paraffins and fatty acids. This is due to the complex and heterogeneous structure of these compounds in the case of commercial products. On the other hand, the measuring instrument should be selected very carefully, including its measuring principle and...