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Novel single-stranded DNA-binding proteins from extreme psychrophilic bacterium Psychromonas ingrahamii 37
PublicationWe report the identification and characterization of the single-stranded DNA binding protein (SSB) from extreme psychrophilic bacterium Psychromonas ingrahamii 37 (PinSSB) that grows expotentially at -12°C and may well grow at even lower temperatures. PinSSB is one of the largest known bacterial SSB protein consisting 222 amino acid residues with a calculated molecular mass of 25.1 kDa. The analysis by gel filtration chromatography...
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Novel Nystatin A1 derivatives exhibiting low host cell toxicity and antifungal activity in an in vitro model of oral candidosis
PublicationOpportunistic oral infections caused by Candida albicans are frequent problems in immunocompromised patients. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Given these issues, our investigations have focused on novel derivatives of the antifungal antibiotic Nystatin A1, generated by modifications at the amino...
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Synthesis and biological evaluation of fluorinated N-benzoyl and N-phenylacetoyl derivatives of 3-(4-aminophenyl)-coumarin-7-O-sulfamate as steroid sulfatase inhibitors
PublicationIn the present work, we report convenient methods for the synthesis of 3-(4-aminophenyl)-coumarin-7-O-sulfamate derivatives N-acylated with fluorinated analogues of benzoic or phenylacetic acid as steroid sulfatase (STS) inhibitors. The design of these potential STS inhibitors was supported by molecular modeling techniques. Additionally, computational docking methods were used to determine the binding modes of the synthesized inhibitors...
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Phenotypic consequences of the LYS4 gene disruption in Candida albicans
PublicationThe main scientific purpose of our studies was to verify the hypothesis that homoaconitase (HA) from Candida albicans, an enzyme catalyzing a second step of the α-aminoadipate pathway (AAP) of L-Lys biosynthesis may become a new target for antifungal chemotherapy. Previous studies indicated that the A. fumigatus mutant lacking the functional lysF gene, encoding HA, exhibited attenuated virulence in a low-dose mouse infection model...
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The compositional space of exhaled breath condensate and its link to the human breath volatilome
PublicationBreath analysis is commonly understood to target gaseous or volatile organic compounds (VOCs) for the characterization of different pathologies. Targeted analysis is most effective if a working hypothesis can be based on a plethora of data. The recently published volatilome builds an optimal basis for organizing powerful target sets. However, the origin and pathways of biosynthesis of many VOCs are not known, which complicates...
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Carboxylic acids as efficient corrosion inhibitors of aluminium alloys in alkaline media
PublicationThe efficiency of AA5754 aluminium alloy corrosion inhibition achieved with maleic, malic, succinic, tartaric, citric, tricarballylic acids and serine in alkaline environment (pH 11) was examined. Selected corrosion inhibitors are characterized by different numbers and distribution of carbonyl and hydroxyl groups within their molecules. We have proposed and verified a novel approach for determining the adsorption isotherms based...
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Determination of robenidine in animal feeds by liquid chromatography coupled with diode-array detection and mass spectrometry after accelerated solvent extraction
PublicationRobenidyna (chlorowodorek 1,3-bis[(4-chlorobenzylideno)amino]guanidyny) jest stosowana w celu zapobiegania i leczenia kokcydiozy - pasożytniczej choroby układu pokarmowego wielu zwierząt hodowlanych (kozy, owce, króliki, drób) wywoływanej przez pierwotniaki należące do rzędu Eimeria tenella, E. Necatrix, E. Acervulina, E. Maxima, E. Brunetti, and E. Mivati. Robenidyna wykazuje stosunkowo wysoką skuteczność terapeutyczną, przy niewielkiej...
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In silico modelling for predicting the cationic hydrophobicity and cytotoxicity of ionic liquids towards the Leukemia rat cell line, Vibrio fischeri and Scenedesmus vacuolatus based on molecular interaction potentials of ions
PublicationIn this study we present prediction models for estimating in silico the cationic hydrophobicity and the cytotoxicity (log [1/EC50]) of ionic liquids (ILs) towards the Leukemia rat cell line (IPC-81), the marine bacterium Vibrio fischeri and the limnic green algae Scenedesmus vacuolatus using linear free energy relationship (LFER) descriptors computed by COSMO calculations. The LFER descriptors used for the prediction model (i.e....
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Trihalometany (THM)
PublicationOpisano powstawanie trohalometanów w trakcie chlorowania wody do picia orazdwie metody ich oznaczania z wykorzystaniem ekstrakcji ciecz-ciecz i ozna-czaniem techniką GC-ECD oraz metodą bezpośredniego dozowania próbki wody dokapilarnej kolumny chromatograficznej połączonej z detektorem wychwytu elek-tronów (DAI-GC-ECD).
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The Application of Dynamic Electrochemical Impedance Spectroscopy (DEIS) Technique in Corrosion and Corrosion Inhibition Studies
Publicationorrosion studies have attracted considerable interest in the areas of materials chemistry and industrial chemistry, as it affects the direct and indirect costs of industry, leading to huge economic setbacks due to the need for repair, maintenance, and even shutdowns due corrosion damage. This new volume is a comprehensive resource that presents new and up-to-date, theoretical, and experimental corrosion inhibition studies.
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Sterowanie procesem destylacji z wykorzystaniem regulatorów rozmytych
PublicationProces destylacji jest popularnym przemysłowym sposobem rozdziału ciekłych mieszanin wieloskładnikowych. W artykule rozważana jest mieszanina etanol-woda, będąca powszechnie destylowanym produktem. Celem artykułu jest zaprojektowanie i symulacyjna analiza działania trzech układów sterowania kolumną rektyfikacyjną z wykorzystaniem rozmytych regulatorów: P, PD i PI.
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On the effective properties of foams in the framework of the couple stress theory
PublicationIn the framework of the couple stress theory, we discuss the effective elastic properties of a metal open-cell foam. In this theory, we have the couple stress tensor, but the microrotations are fully described by displacements. To this end, we performed calculations for a representative volume element which give the matrices of elastic moduli relating stress and stress tensors with strain and microcurvature tensors.
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Podstawowe parametry opisujące układ chromatograficzny.
PublicationPodano zasadę procesu chromatograficznego, definicję parametrów opisujących kolumnę tj. selektywność i sprawność, oraz sposoby ich obliczania na podstawie chromatogramu. Podano również podstawowe kryteria doboru fazy stacjonarnej tj. wielkość, kształt ziaren, porowatość, powierzchnia właściwa i inne. Scharakteryzowano rozpuszczalniki które mogą być fazami ruchomymi.
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Wykorzystanie techniki mikroekstrakcji do fazy stacjonarnej w analityce środowiskowej.**2002, 122 s. 25 rys. 31 tab. bibliogr. 465 poz. maszyn. Rozprawa doktorska /10.12.2002/ Wydz. Chem. PG Promotor: prof. dr hab. inż. Jacek Namieśnik
PublicationPrzeprowadzone badania obejmowały: opracowanie podstaw metodycznych oznacza-nia lotnych amin alifatycznych w powietrzu za pomocą GC ze wzbogacaniem te-chniką SPME; określenie warunków oraz parametrów pracy urządzenia do SPME wwarunkach badań modelowych; zbadanie wpływu temperatury, wilgotności i stę-żenia gazowej mieszaniny wzorcowej na efektywność procesu wzbogacania anali-tów z wykorzystaniem urządzenia do SPME; porównanie...
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Stateczność czołowego obwałowania nasypu przeciwpowodziowego Jeziora Druzno
PublicationPrzedstawiono analizę stateczności czołowego obwałowania przeciwpowodziowego Jeziora Druzno w miejscowości Nowe Dolno. Obliczenia przeprowadzono zarówno w naprężeniach całkowitych jak i efektywnych uproszczoną metodą Bishopa oraz metodą Felleniusa-Peterssona. Uzyskano wysokie wartości minimalnego wskaźnika stateczności, zapewniające znaczny zapas stateczności nasypu podczas długotrwałych piętrzeń wody w jeziorze. Mogłoby to wskazywać...
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The Action Mechanisms, Anti-Cancer and Antibiotic-Modulation Potential of Vaccinium myrtillus L. Extract
PublicationHerbal medicinal products containing Vaccinium myrtillus L. (bilberry) fruits and fruit extracts are widely available in the market. Although bilberry leaves and stems are considered as bio-waste, they contain much higher levels of phenolic compounds than fruits. The study aimed to investigate the antimicrobial and anticancer potential of aerial part extracts from Vaccinium myrtillus L. (V. myrtillus, VM) plants harvested at high...
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Young Shoots of White and Red Headed Cabbages Like Novel Sources of Glucosinolates as Well as Antioxidative Substances
PublicationMost literature data indicate that the diet rich in plant products reduces the risk of developing chronic non-communicable diseases and cancer. Brassica vegetables are almost exclusively synthesizing glucosinolates. Glucosinolates are higher in sprouts than in mature plants, being related to the activity of the specific myrosinase involved in the degradation of glucosinolates during developmental stages. This study compares the...
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Extracellular proteolytic activity of Deinococcus geothermalis
PublicationProduction of extracellular protease by extremophilic bacteria Deinococcus geothermalis cultivated in liquid media containing 0.1% (w/v) of peptone K, 0.1% yeast extract and 0.2% marine salt reached a maximum in 14 h of the cell growth at 45°C and pH 8.0. The enzyme was purified by a two-step procedure using fractionation by a graded ammonium sulphate precipitation technique and gel filtration on Sephadex G-100 column. Protease...
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Sensitive simultaneous determination of 19 fluorobenzoic acids in saline waters by solid-phase extraction and liquid chromatography–tandem mass spectrometry
PublicationA solid-phase extraction (SPE) procedure using C18 stationary phase was optimized for the preconcentration of 19 fluorinated derivatives of benzoic acid (FBA): mono-, di-, tri-, and tetrafluorosubstituted in the ring, trifluoromethylbenzoic acid and 3,5-bistrifluoromethyl benzoic acid from undiluted salt-rich (>20%) reservoir waters. Quantitative (>90%) retention/elution of 16 out of 19 analyte compounds was achieved allowing a...
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Metal dusting phenomena of 501 AISI furnace tubes in refinery fractional distillation unit
PublicationThe purpose of this investigation was to conduct the failure analysis of 501 AISI furnace tubes places before distillation column in fractional distillation unit. The investigated furnace tubes were planned to work for ten years however after just two years of exploitation <30% of the material left. The observed corrosion process had the intense and complex character. The well-adhered shiny black deposits and deep, round pits were...
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Phytochemical composition and biological activities of differently pigmented cabbage (Brassica oleracea var. capitata) and cauliflower (Brassica oleracea var. botrytis) varieties
PublicationBACKGROUND:Brassica plants contain awide spectrumofbioactive components that are responsible for their health-promoting potential such as vitamins, polyphenols and glucosinolates. This study attempted to relate the composition of bioactive phytochemicals and chosen biological activities (antioxidant, cytotoxic, anti-genotoxic, and influence on enzymatic activities) for extracts from differently pigmented cabbage (white and red)...
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Evaluation of headspace solid-phase microextraction for the analysis of volatile carbonyl compounds in spirits and alcoholic beverages
PublicationOpracowano metodę oznaczania C1-C6 związków karbonylowych w układzie GC-ECD w roztworach alkoholowych poprzez derywatyzację pentafluorobenzylohydroksy-aminą i mikroekstrakcję w fazie stacjonarnej z fazy nadpowierzchniowej. Zoptymalizowano warunki eksperymantalne: zawartość alkoholu, czas ekspozycji, temperaturę i sposób mieszania próbki. W metodzie tej najpierw przeprowadza się rozcieńczenie spirytusu lub napojów alkoholowych do...
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Carbon nanotubes chemically derivatized with rebox systems as mediators for biofuel cell applications
PublicationEnzymatyczne bioogniwa paliwowe to urządzenia wykorzystujące enzymy do przemiany energii chemicznej w elektryczną. Zyskana w ten sposób energia może służyć do zasilania wszczepialnych urządzeń (np. czujników glukozy, rozruszników serca).Przedstawiono sposób otrzymywania i właściwości bioelektrod, w których wykorzystano nanorurki węglowe modyfikowane mediatorami enzymatycznych reakcji redoks. Do nanorurek przyłączano zarówno mediatory...
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Carbon Nanotubes Chemically Derivatized with Redox Systems as Mediators for Biofuel Cell Applications
PublicationEnzymatyczne bioogniwa paliwowe to urządzenia wykorzystujące enzymy do przemiany energii chemicznej w elektryczną. Zyskana w ten sposób energia może służyć do zasilania wszczepialnych urządzeń (np. czujników glukozy, rozruszników serca). Przedstawiono sposób otrzymywania i właściwości bioelektrod, w których wykorzystano nanorurki węglowe modyfikowane mediatorami enzymatycznych reakcji redoks. Do nanorurek przyłączano zarówno mediatory...
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Carbon Nanotubes Chemically Derivatize with Redox Systems as Mediators for Biofel Cell Applicatoions
PublicationEnzymatyczne bioogniwa paliwowe to urządzenia wykorzystujące enzymy do przemiany energii chemicznej w elektryczną. Zyskana w ten sposób energia może służyć do zasilania wszczepialnych urządzeń (np. czujników glukozy, rozruszników serca).Przedstawiono sposób otrzymywania i właściwości bioelektrod, w których wykorzystano nanorurki węglowe modyfikowane mediatorami enzymatycznych reakcji redoks. Do nanorurek przyłączano zarówno mediatory...
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A Note on Reduced Strain Gradient Elasticity
PublicationWe discuss the particular class of strain-gradient elastic material models which we called the reduced or degenerated strain-gradient elasticity. For this class the strain energy density depends on functions which have different differential properties in different spatial directions. As an example of such media we consider the continual models of pantographic beam lattices and smectic and columnar liquid crystals.
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Analiza weryfikująca poprawność istniejącego układu ochrony przed korozją i osadami instalacji DRW4 w kontekście obecnych warunków pracy instalacji
PublicationCelem pracy były pomiary korozyjności kondensatów pochodzących z kolumny destylacyjnej z dodatkiem neutralizatora oraz inhibitora korozji, ponadto przeprowadzono badania SEM i EDX produktów korozji pochodzących z rurek chłodnicy powietrznej. Wykazano, że znacznie większą agresywnością charakteryzują się kondensaty które pochodzą z przerobu ropy naftowej zawierającą slopy.
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Determination of solvents residues in vegetable oils and pharmaceuticals by headspace analysis and capillary gas chromatography.
PublicationPrzedstawiono wyniki zastosowania techniki analizy fazy nadpowierzchniowej w połączeniu z kapilarną chromatografią gazową do oznaczania wybranych rozpuszczalników organicznych w próbkach olejów jadalnych i produktów farmaceutycznych. Oznaczane rozpuszczalniki to: benzen, toluen, heksan oraz chlorowcopochodne węglowodorów alifatycznych. Opracowaną procedurę poddano walidacji. Wyznaczono granicę wytrzymalności, oznaczalności, liniowość...
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The Point Estimate Method in a Reticulated Shell Reliability Analysis
PublicationThe objective of this paper is to present an application of the point estimate method (PEM) to determine the probabilistic moments for engineering structures. Reliability analysis is illustrated by two examples: an estimation of the critical force in linear elastic buckling analysis and a reticulated shell limit load determinations. Calculations were also made using Monte Carlo method. It has been shown the practical usefulness...
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Quality evaluation of agricultural distillates using different types of electronic noses
PublicationThe paper presents the results of investigation on quality evaluation of agricultural distillates using a prototype of electronic nose instrument and a commercial electronic nose of Fast/Flash GC type – HERACLES II. The prototype was equipped with TGS type semiconductor sensors. HERACLES II included two chromatographic columns with different polarity of stationary phase and two FID detectors. In case of the prototype volatile fraction...
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Impact of Geometrical Imperfections on Estimation of Buckling and Limit Loads in a Silo Segment Using the Vibration Correlation Technique
PublicationThe paper examines effectiveness of the vibration correlation technique which allows determining the buckling or limit loads by means of measured natural frequencies of structures. A steel silo segment with a corrugated wall, stiffened with cold-formed channel section columns was analysed. The investigations included numerical analyses of: linear buckling, dynamic eigenvalue and geometrically static non-linear problems. Both perfect...
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Distillation cleanup preceded gc determination of short-chain monocarboxylic acids in aqueous and solid samples of wastewater origin = Oznaczanie krótkołańcuchowych kwasów monokarboksylowych w próbkach wodnych i stałych pochodzących z oczyszczalni ścieków z wykorzystaniem chromatografii gazowej poprzedzonej destylacją
PublicationShort-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work...
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Response of high voltage disconnector under seismic excitation - experimental and numerical study
PublicationThe efficiency of the energetic infrastructure system is a very import safety issue in the region experienced by the ground motion. The aim of the present paper is to show the results of the experimental and numerical study focused on the earthquake-induced response of the high voltage disconnector, which is an important element of energetic network. First, the impact tests as well as the sweep-sine shaking table tests were conducted....
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Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1
PublicationSolid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...
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Local buckling of thin-walled channel member flange made of aluminum alloy
PublicationThe paper deals with local stability of the thin-walled compressed flange of channel columns and beams made of aluminum alloy. The aim of paper is to find critical stress of local buckling of the flange member taking into account the web-flange interaction in linear and nonlinear elastic range of the member material. The governing differential equation of the problem is derived with aid of the principle of stationary total potential...
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Catalytic impact of alloyed Al on the corrosion behavior of Co50Ni23Ga26Al1.0 magnetic shape memory alloy and catalysis applications for efficient electrochemical H2 generation
PublicationThe electrochemical and corrosion behaviour of Co50Ni23Ga27-xAlx (x = 0 and 1.0 wt%) magnetic shape memory alloys (MSMAs) was studied in 0.5 M NaCl solutions using various electrochemical techniques. Results showed remarkable activation of the tested MSMA toward pitting corrosion upon alloying it with Al. XPS examination confirmed the activation influence of alloyed Al. It proved that the presence of Al in the alloy's matrix weakens...
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A theoretical probe into the effects of material and operational variables on water purification with zeolite membranes
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublicationA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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An air-assisted dispersive liquid phase microextraction method based on a hydrophobic magnetic deep eutectic solvent for the extraction and preconcentration of melamine from milk and milk-based products
PublicationIn the current research, a fast and sustainable air-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction followed by UV–Vis spectrophotometry measurements was optimized for the extraction and determination of melamine in milk and milk-based products. The central composite design was applied for the optimization of factors affecting the recovery of melamine. Quantitative extraction of...
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Interfacial water controls the process of adsorption of hyperactive antifreeze proteins onto the ice surface
PublicationA mechanism of interactions between the ice-binding surface of a hyperactive antifreeze protein molecule and the ice surface is proposed, involving the influence of water present between the two surfaces on the behavior of the approaching molecule. It is demonstrated that the interfacial water, even before its full solidification, can act as a factor that pushes away or pulls nearer the protein molecule to ensure its proper positioning....
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Experimental Investigations of Fracture Process Using DIC in Plain and Reinforced Concrete Beams under Bending
PublicationThe fracture behaviour of concrete and reinforced concrete beams under quasi-static three-point bending was comprehensively investigated with experiments at laboratory scale. The eight various concrete mixes were tested. The influence of the shape, volume and size of aggregate particles and reinforcement on concrete fracture under bending was studied. Displacements on the surface of concrete beams were measured by means of the...
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Comparative effects of biochar-nanosheets and conventional organic-amendments on health risks abatement of potentially toxic elements via consumption of wheat grown on industrially contaminated-soil
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Evaluation of the Effect of Four Bioactive Compounds in Combination with Chemical Product against Two Spider Mites Tetranychus urticae and Eutetranychus orientalis(Acari: Tetranychidae)
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Biopesticides, Safety Issues and Market Trends
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Investigating the Impact of Curing System on Structure-Property Relationship of Natural Rubber Modified with Brewery By-Product and Ground Tire Rubber
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Reactive Sintering of Ground Tire Rubber (GTR) Modified by a Trans-Polyoctenamer Rubber and Curing Additives
PublicationThe proposed method of ground tire rubber (GTR) utilization involves the application of trans-polyoctenamer rubber (TOR), a commercially available waste rubber modifier. The idea was to investigate the influence of various curing additives (sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), dibenzothiazole disulfide (MBTS) and di-(2-ethyl)hexylphosphorylpolysulfide (SDT)) on curing characteristics, physico-mechanical, thermal,...
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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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Evaluation and rationale of the performance of several elastomeric composites incorporating devulcanized EPDM
Publicationthylene Propylene Diene rubber (EPDM), is present in many applications. However, its crosslinked structure makes difficult its recycling. The use of devulcanized EPDM, (dEPDM) as a component of elastomeric composites, is a real possibility to reuse EPDM scraps. In this study, three matrices (natural rubber (NR), styrene butadiene rubber (SBR) and EPDM rubber) have been tested including devulcanized EPDM as a recycled component....
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Induction of unique structural changes in guanine-rich DNA regions by the triazoloacridone C-1305, a topoisomerase II inhibitor with antitumor activities.
PublicationCelem pracy było scharakteryzowanie odziaływania związku C-1305 z DNA w porównaniu do innych inhibitorów topoizomerazy II. Badania pokazują, że C-1305 odziaływuje preferencyjnie z parami CG, interkaluje do DNA i zaburza sąsiednie otoczenie w bardzo charakterystyczny sposób, który nie został zaobserwowany u pozostałych 22 badanych związków.
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The application of an open tubular trap in analysis of organic air pollutants
PublicationOpisano możliwości wykorzystania odcinka handlowej kapilarnej kolumny chromatograficznej do pobierania próbek analitów z powietrza w celu ich chromatograficznego oznaczenia. Opracowany sposób opary jest na wykorzystaniu techniki równowagowej. Stężenia analitów w badanym medium mogą być obliczone na podstawie znajomości wartości odpowiednich współczynników podziału wyznaczonych w trakcie badań modelowych.