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Wyniki wyszukiwania dla: LC–MS/MS ANALYSIS
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On the fast BSS transition algorithms in the IEEE 802.11r local area wireless networks
PublikacjaHandover performance is critical to support multimedia services that are becoming increasingly available over the wireless devices. The high transition delay can be unaccepted for such services or can be a source of disruption on the session. On the other side, IEEE 802.11 standard is being extended with new functionalities. Security and QoS features, included in recent IEEE 802.11-2007 standard, add management frames that are...
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Organic and conventional kiwifruit, myths versus reality: antioxidant, antiproliferative and helth effects
PublikacjaComparison between organic and conventional kiwifruit cultivars 'Hayward' and 'Bidan', which was done by four radical scavenging assays, ESI-MS, and DSC measurements, showed significant differences between the cultivars. Such results were not estimated in kiwifruit growing under organic and conventional conditions. The extraction of bioactive compounds was done by two different methods: sequential extraction with ethyl acetate...
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Lightning impulse efficiency of horizontal earthings
PublikacjaSystem uziemień współczesnych obiektów jest zwykle bardzo rozległy, a na łączenie poszczególnych elementów uziemiających za pomocą głównej szyny wyrównania potencjałów uwzględnia także uziemienia stacji transformatorowej. Ocena przydatności takiego systemu uziemień do celów ochrony odgromowej nie jest prosta, bo tylko jego część określana, jako długość efektywna bierze udział w odprowadzaniu do gruntu prądu piorunowego. Praca zawiera...
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Charakterystyka porównawcza zgazowania drewna bukowego i RDF w reaktorze przeciwprądowym
PublikacjaRozproszone małe układy produkcji ciepła to coraz popularniejszy trend w energetyce. Praca opisuje możliwości zgazowania biomasy i odpadów w reaktorze przeciwprądowym małej mocy. Zgazowanie odpadów jest obiecującą metodą ich utylizacji. W pracy porównano rozkład temperatur uzyskany podczas zgazowania biomasy i WPS dla całej wysokości reaktora. Porównane zostały składy gazu generatorowego oraz jego kaloryczność. Podczas prób badano...
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Kapilarna chromatografia gazowa fazy nad-powierzchniowej – HS-CGC w badaniach składu lotnych produktów hydrolizy biomasy ligno-celulozowej – BMLC
PublikacjaW pracy przedstawiono sposoby obróbki biomasy ligno-celulozowej, których celem jest rozpulchnienie struktury surowca i zwiększenie dostępności struktur dla czynników hydrolizujących. Na podstawie przeglądu literatury wskazano na możliwe do zidentyfikowania związki obecne w hydrolizatach z biomasy ligno-celulozowej. Opracowano metodykę oraz zbadano możliwość oznaczania lotnych produktów hydrolizy chemicznej z wykorzystaniem techniki...
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Studies on the formation of formaldehyde during 2-ethylhexyl 4-(dimethylamino)benzoate demethylation in the presence of reactive oxygen and chlorine species
PublikacjaIn order to protect the skin from UV radiation, personal care products (PCPS) often contain chemical UV-filters. These compounds can enter the environment causing serious consequences on the water ecosystems. The aim of this study was to examine, the effect of different factors, such as UV light, the presence of NaOCl and H2O2 on the formaldehyde formation during popular UV filter, 2-ethylhexyl 4-(dimethylamino)benzoate (ODPABA)...
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Evaluation of the photoprotective effect of β-cyclodextrin on the emission of volatile degradation products of ranitidine
PublikacjaThe process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of ˇ-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Samples of inclusion complexes...
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Determination of fuel combustion product in airport runoff water samples using liquid–liquid extraction with gas chromatography–spectrometry
PublikacjaDetermination of xenobiotics in samples of airport runoff water is both a complex and indispensable task due to an increasing threat resulting from the activities of numerous airports. The aim of this study was to develop, optimize, and validate a procedure based on liquid–liquid extraction (LLE) coupled with gas chromatography–mass spectrometry (GC–MS) for the determination of polycyclic aromatic hydrocarbons (PAHs). So far, no...
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Evaluation of the photoprotective effect of ˇ-cyclodextrin on the emission of volatile degradation products of ranitidine
PublikacjaThe process of the photo-excitation of ranitidine hydrochloride (RAN) in a solid state makes visible changes to its colour and generates an unpleasant odour. The purpose of the present study was to observe the protective effects of ˇ-cyclodextrin (CD) complexation as well as the effect of the mixture of two stoichiometries 1:1 and 1:2 (RAN:CD, IC) on the photostability of samples in a solid state. Sam- ples of inclusion complexes...
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Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
PublikacjaA dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature....
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Divulging the anti-acetylcholinesterase activity of Colletotrichum lentis strain KU1 extract as sustainable AChE active site inhibitors
PublikacjaAlzheimer’s disease (AD), also called senile dementia is a neurodegenerative disease seen commonly in the elderly and is characterised by the formation of β-amyloid plaques and neurofbrillary tangles (NFT). Though a complete understanding of the disease is lacking, recent studies showed the role of the enzyme acetylcholinesterase (AChE) in pathogenesis. Finding new lead compounds from natural sources has always been a quest for...
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Sample preparation procedure using extraction and derivatization of carboxylic acids from aqueous samples by means of deep eutectic solvents for gas chromatographic-mass spectrometric analysis
PublikacjaThe paper presents a new procedure for the determination of organic acids in a complex aqueous matrixusing ultrasound-assisted dispersive liquid–liquid microextraction followed by injection port derivati-zation and GC–MS analysis. A deep eutectic solvent (choline chloride: 4-methylphenol in a 1:2 mol ratio)was used both as an extracting solvent and as a derivatizing agent to yield ion pairs which were next con-verted to methyl...
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Phenolic Content and Related Antioxidant Activities in in vitro Cultures of Cephalotaxus Harringtonia L. Grown in Egypt
PublikacjaAbstract: Quantitative estimation of the total phenolics, total flavonoids, antioxidant activity and HPLC analysis of phenolic compounds in the mother plant, in vitro shooting and callus cultures of Cephalotaxus harringtonia L. grown in Egypt were measured. For shooting behaviour, using Woody plant medium (WPM) with 2 mg/l Benzyladinin (BA) in the second subculture gave the highest number of shootlet/explant (2.33 shootlet/explant)...
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Inactivation of glucosamine-6-phosphate synthase by N3-oxoacyl derivatives of L-2,3-diaminopropanoic acid
PublikacjaN3-oksoacylowe pochodne kwasu l-2,3-diaminopropanowego zawierające ugrupowanie epoksydowe lub układ sprzężonych wiązań podwójnych inaktywują syntaze glukozamino-6-fosforanu (GlcN-6-P) z S. cerevisiae. Wyniki badań kinetycznych inaktywacji enzymu wskazują na dwuetapowy przebieg tej reakcji, przy czym tworzenie kompleksu enzym:ligand poprzedza nieodwracalną modyfikację enzymu. Badane związki różniły się powinowactwem do centrum aktywnego...
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In search of molecular precursors for cadmium sulfide-new complexes with a sulfur-rich kernel: cadmium(II) tri-tert-butoxysilanethiolates with additional diethyldithiocarbamato ligand
PublikacjaW ramach rozprawy opracowano metodę syntezy związków koordynacyjnych kadmu zawierających mieszane ligandy S-donorowe, które stanowią reszta tri-tert-butoksysilanotiolanowa oraz ditiokarbaminianowa. Zostały one poddane badaniom za pomocą analizy składu pierwiastkowego, metod spektroskopowych (FTIR, FIR, UV-Vis, NMR, MS) oraz termicznych. W celu osadzenia cienkich warstw wybranych związków posłużono się techniką nakładania obrotowego...
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Oddziaływanie przepięć atmosferycznych na bezpieczniki SN: badania wstępne
PublikacjaObserwowane sš liczne przypadki błędnego działania w czasie burz bezpieczników SN chronišcych transformatory słupowe SN/nn. W artykule przedstawiono wyniki eksperymentów i symulacji wpływu przepięcia atmosferycznego na zachowanie się bezpieczników SN. Zauważono, że udary krótsze niż około 15 ms nie powodujš znacznego zwiększenia całki Joule`a pršdu płynšcego przez bezpiecznik mogšcego doprowadzić do jego zadziałania. Choć w rzeczywistoci...
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Surface sediments pollution due to shipwreck s/s “Stuttgart”: a multidisciplinary approach
PublikacjaShipwrecks may pose a serious source of pollution for marine ecosystems. For this reason, it is of great importance to perform a marine ecosystem risk assessment due to plausible wreck presence. One of elements of such an assessment is determining the state of the environment in the vicinity of the wreck. In the work presented, the results of studies on surface sediments samples collected around the s/s Stuttgart ship sunk during...
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The structure of levorin A3, a minor component of levorin complex
PublikacjaBudowa chemiczna składnika kompleksu leworyn, leworyny A3, została ustalona na podstawie analizy z wykorzystaniem metod spektroskopowych UV, MS i NMR metoksykarbonylometyloamido pochodnej leworyny A3. Widmo UV wskazało obecność chromoforu heptaenowego. Ciężar cząsteczkowy leworyny A3 ustalono jako 1110 j.m. za pomocą spektrometrii masowej z wykorzystaniem techniki FAB, co po uwzględnieniu uwarunkowań biogenetycznych pozwoliło wydedukować...
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The Method of Multi-criteria Analysis to Support the Decision on Load or Micro-generation Connection to a Low- or Medium-voltage Power Grid
PublikacjaThis paper presents a method that supports the decision in terms on selecting the best option of a load connection to a low- or medium-voltage power distribution grid, and of a micro-generation source connection to a low-voltage grid. The method is based on the search for the option with the lowest aggregate assessment measure, which is the weighted average of partial assessment measures determined for each of eight considered...
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Chemical composition, antioxidant and anticancer effects of the seeds and leaves and indigo (polygonum tinctorium Ait.) Plant
PublikacjaSeeds and leaves of indigo (Polygonum tinctorium Ait.) plant were investigated and compared with another medicinal plant named prolipid for their properties such as chemical composition, antioxidant, and anticancer effects by Fourier transform infrared, three-dimensional fluorescence spectroscopy, and electrospray ionization-MS in negative mode. It was found that polyphenols, flavonoids, and flavanols were significantly higher...
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Design, synthesis and biological evaluation of novel N-phosphorylated and O-phosphorylated tacrine derivatives as potential drugs against Alzheimer’s disease
PublikacjaIn this work, we designed, synthesised and biologically investigated a novel series of 14N- and O-phosphorylated tacrine derivatives as potential anti-Alzheimer’s disease agents. In the reaction of 9-chlorotacrine and corresponding diamines/aminoalkylalcohol we obtained diamino and aminoalkylhydroxy tacrine derivatives. Next, the compounds were acid to give final products 6–13 and 16–21 that were characterised by 1H, 13 C, 31P...
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Preparation of Allyl Alcohol Oligomers Using Dipicolinate Oxovanadium(IV) Coordination Compound
PublikacjaCurrently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H2O)2] 2 H2O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization–time-of-flight...
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Improvements and new functionalities of UNRES server for coarse-grained modeling of protein structure, dynamics, and interactions
PublikacjaIn this paper we report the improvements and extensions of the UNRES server (https://unres-server.chem.ug.edu.pl) for physics-based simulations with the coarse-grained UNRES model of polypeptide chains. The improvements include the replacement of the old code with the recently optimized one and adding the recent scale-consistent variant of the UNRES force field, which performs better in the modeling of proteins with the β and the...
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Przyrząd wirtualny do szacowania niepewności pomiaru mocy chwilowej.
PublikacjaW artykule przedstawiono zagadnienie dotyczące wykorzystania przyrządu wirtualnego do szacowania niepewności pomiaru mocy chwilowej. Analiza dotyczy układu do diagnostyki łożysk tocznych, składającego się z przetworników: napięcia oraz prąd-napięcie, który wykorzystano do badań diagnostycznych łożysk silników indukcyjnych metodą, opartą na pomiarze i analizie sygnałów napięcia i prądu pobieranych przez maszynę. Zaprezentowano opracowany...
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Nanodiamond phantoms mimicking human liver: perspective to calibration of T1 relaxation time in magnetic resonance imaging
PublikacjaPhantoms of biological tissues are materials that mimic the properties of real tissues. This study shows the development of phantoms with nanodiamond particles for calibration of T1 relaxation time in magnetic resonance imaging. Magnetic resonance imaging (MRI) is a commonly used and non-invasive method of detecting pathological changes inside the human body. Nevertheless, before a new MRI device is approved for use, it is necessary...
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Assessment of Sewage Molecular Markers: Linear Alkylbenzenes in Sediments of an Industrialized Region in Peninsular Malaysia
PublikacjaIn this study, the use of linear alkylbenzenes (LABs) was employed to pinpoint the sources of human activity that cause detrimental impacts on the coastal environment and river ecosystems. LABs were detected using GC–MS in sediment samples assembled from Kim Kim River (KKR) and the Port Dickson coast (PDC). To assess the significance of variations in the distribution and concentrations of LABs across the sampling sites, this study...
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Hydroxyl and sulfate radical-based degradation of ciprofloxacin using UV-C and/or Fe2+-catalyzed peroxymonosulfate: Effects of process parameters and toxicity evaluation
PublikacjaCiprofloxacin (CIP) is a valuable antibiotic and discharged in huge quantities in aquatic environment. Different •OH and SO4•−-based advanced oxidation technologies (AOTs), e.g., Fe2+/PMS, UV-C/PMS, and UV-C/Fe2+/PMS are developed for treatment of CIP. The removal of CIP by Fe2+/PMS, UV-C/PMS and UV-C/Fe2+/PMS was 63, 77, and 87 %, respectively, under identical conditions which showed better performance of UV-C/Fe2+/PMS. The UV-C/Fe2+/PMS...
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Urban dew formation efficiency and chemistry in Poland
PublikacjaThe measurements of dew formation efficiency and chemistry were performed in Poland in September 2009, as a part of a longer, two-year sampling campaign. Pairs of sites, representing centers of major Polish cities and rural conditions in three different regions, were compared. With the aim to get more detailed landuse-oriented characteristics of dew, two additional sites were set close to Wroclaw. Collection of dew at each site...
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Silicon’s Influence on Polyphenol and Flavonoid Profiles in Pea (Pisum sativum L.) under Cadmium Exposure in Hydroponics: A Study of Metabolomics, Extraction Efficacy, and Antimicrobial Properties of Extracts
PublikacjaThe current study aimed to investigate the impact of silicon (Si) supplementation in the form of Na2SiO3 on the metabolome of peas under normal conditions and following exposure to cadmium (Cd) stress. Si is known for its ability to enhance stress tolerance in various plant species, including the mitigation of heavy metal toxicity. Cd, a significant contaminant, poses risks to...
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Role of Silicon in Counteracting Cadmium Stress in Pea Plants (Pisum sativum L.): Insights Into Cadmium Binding Mechanisms and Pectin Methylesterase Activity
PublikacjaPurpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity...
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Bioreactor shoot cultures of Rhododendron tomentosum (Ledum palustre) for a large-scale production of bioactive volatile compounds
PublikacjaRhododendron tomentosum Harmaja (Ledum palustre), a peat bog plant from Ericaceae family, has been used in traditional medicine as the anti-arthritis agent. Although modern researches confirm its anti-inflammatory properties, it remains threatened by habitat degradation and possibilities to collect this endangered species from its natural environment for further biological activity studies are limited. Therefore, R. tomentosum...
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Mechanical Properties and Residual Stress Measurements of Grade IV Titanium and Ti-6Al-4V and Ti-13Nb-13Zr Titanium Alloys after Laser Treatment
PublikacjaNowadays, surface engineering focuses on research into materials for medical applications. Titanium and its alloys are prominent, especially Ti-6Al-4V and Ti-13Nb-13Zr. Samples made of pure grade IV titanium and the titanium alloys Ti-6Al-4V and Ti-13Nb-13Zr were modified via laser treatment with laser beam frequency f = 25 Hz and laser beam power P = 1000 W during a laser pulse with duration t = 1 ms. Subsequently, to analyze...
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Importance of Bile Composition for Diagnosis of Biliary Obstructions
PublikacjaDetermination of the cause of a biliary obstruction is often inconclusive from serum analysis alone without further clinical tests. To this end, serum markers as well as the composition of bile of 74 patients with biliary obstructions were determined to improve the diagnoses. The samples were collected from the patients during an endoscopic retrograde cholangiopancreatography (ERCP). The concentration of eight bile salts, specifically...
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Structure and Stability Characterization of Natural Lake Pigments Made from Plant Extracts and Their Potential Application in Polymer Composites for Packaging Materials
PublikacjaNatural dyes were extracted from various plant sources and converted into lake pigments based on aluminum and tin. Three different plants (weld, Persian berries, and Brazilwood) were chosen as representative sources of natural dyes. High-performance liquid chromatography (HPLC) and triple-quadrupole mass spectrometry (QqQ MS) were used to identify dyestuffs in the raw extracts. The natural dyes and lake pigments were further characterized...
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Insight into Potassium Vanadates as Visible-Light-Driven Photocatalysts: Synthesis of V(IV)-Rich Nano/Microstructures for the Photodegradation of Methylene Blue
PublikacjaPhotocatalysis is regarded as a promising tool for wastewater remediation. In recent years, many studies have focused on investigating novel photocatalysts driven by visible light. In this study, K2V6O16·nH2O nanobelts and KV3O8 microplatelets were synthesized and investigated as photocatalysts. Samples were obtained via the facile method based on liquid-phase exfoliation with ion exchange. By changing the synthesis temperature...
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Impact of selected parameters of the fermentation process of wine and wine itself on the biogenic amines content: Evaluation by application of chemometric tools
PublikacjaThe demand for safer foods has promoted more research into biogenic amines (BAs) over the past few years, however, there are still some questions that remain unanswered. Despite the fact that BAs are present in wine and can cause toxic effect to the body, a shared regulation limiting the amounts of BAs in wine is still lacking. A detailed understanding of their presence in wine is also important for the food trade sector. Therefore,...
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Visible light photocatalysis employing TiO2/SrTiO3-BiOI composites: Surface properties and photoexcitation mechanism
PublikacjaA series of binary TiO2/SrTiO3 and ternary TiO2/SrTiO3_BiOI composites have been synthesized using multistep preparation method. Characterization of the obtained photocatalysts covered complex analysis including morphology + y (SEM), BET specific surface area, porosity, optical properties (DRS), chemical composition of surface (XPS), crystal structure and crystal size (XRD). UV–vis and Vis ligh induced photocatalytic activity was...
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublikacjaIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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Experimental and theoretical studies on the photodegradation of 2-ethylhexyl 4-methoxycinnamate in the presence of reactive oxygen and chlorine species
Publikacja2-Ethylhexyl 4-methoxycinnamate (EHMC) is one of the most commonly used sunscreen ingredient. In this study we investigated photodegradation of EHMC in the presence of such common oxidizing and chlorinating systems as H2O2, H2O2/HCl, H2O2/UV, and H2O2/HCl/UV. Reaction products were detected by gas chromatography with a mass spectrometric detector (GC-MS). As a result of experimental studies chloro-substituted 4-methoxycinnamic...
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Bioactive compounds and the antioxidant capacity in new kiwi fruit cultivars
PublikacjaThe aim of this investigation was to find the best among seven different kiwi fruit cultivars (‘Hayward’, ‘Daheung’, ‘Haenam’, ‘Bidan’, ‘Hort16A’, ‘Hwamei’ and ‘SKK12’) for human consumption and to classify them as groups. Therefore, the contents of bioactive compounds and the level of antioxidant capacities of these cultivars were determined in four different extracts and compared. It was found that the contents of the bioactive...
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How proteins bind to DNA: target discrimination and dynamic sequence search by the telomeric protein TRF1
PublikacjaTarget search as performed by DNA-binding proteins is a complex process, in which multiple factors contribute to both thermodynamic discrimination of the target sequence from overwhelmingly abundant off-target sites and kinetic acceleration of dynamic sequence interrogation. TRF1, the protein that binds to telomeric tandem repeats, faces an intriguing variant of the search problem where target sites are clustered within short fragments...
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Preparation, characterization and anti-colitis activity of curcumin-asafoetida complex encapsulated in turmeric nanofiber
PublikacjaUlcerative colitis (UC) is a main form of inflammatory bowel disease (IBD). Asafoetida (ASF) and turmeric have traditionally been used for the treatment of various inflammatory diseases, including UC, because ASF is rich in sulfur compounds and turmeric contains curcumin (CUR). Turmeric nanofiber (TNF), the modified cell wall component of turmeric is considered to play important role in the human diet, health and can be used as...
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Transportable, Portable and Micro Gas Chromatographs
PublikacjaSignificant benefits can be obtained by miniaturization of conventional benchtop gas chromatographs. The attractive features arising from miniaturization include low-power requirements, low heat capacity of separation columns, low consumption of mobile phase, enhanced performance, higher portability, and easily coupling to detectors and secondary chromatographic systems. In separation sciences, including gas phase separations,...
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Contamination of Runoff Water at Gdańsk Airport (Poland) by Polycyclic Aromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs)
PublikacjaAirport runoff can contain high concentrations of various pollutants, in particular polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), the environmental levels of which have to be monitored. Airport runoff water samples, collected at the Gdańsk-Rębiechowo Airport from 2008 to 2009, were analysed for PAHs and PCBs by gas chromatography. The aromatic fractions were separated by liquid-liquid extraction...
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Accelerated solvent extraction-gas chromatographic determination of acidic herbicides in soil
PublikacjaPrzyspieszona ekstrakcja rozpuszczalnikiem z wykorzystaniem wody jako ekstraktanta okazała się skutecznym sposobem izolacji herbicydów kwasowych (MCPP, MCPA, 2,4-D, 2,4,5-T, PCP, dinoseb, dinoterb) z próbek gleby. Wysoka zawartość substancji iłowych powodowała problemy techniczne, które udało się pokonać poprzez zwiększenie stosunku piasku do gleby w celce ekstrakcyjnej. Anality przenoszono z ekstraktu wodnego do rozpuszczalnika...
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Lower rim substituted tert-butylcalix[4]arenes.Part 8: Calix[4]arenes with dialkoxyphosphoryl functions. Synthesis and complexing properties
PublikacjaW pracy przedstawiono syntezę i charakterystykę otrzymanych związków (1, 2), pochodnych alkoksyfosforylowych p-tert-butylokaliks[4]arenu: 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-diizopropoksyfosforylopropoksy)kaliks[4]arenu (1) oraz 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-methoksyetoksyfosforylopropoksy)kaliks[4]arenu (2). Zbadano właściwości jonoforowe związków 1 i 2 w membranie elektrod jonoselektywnych,...
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Chemical composition of shells from red (Strongylocentrotus franciscanum) and green (Strongylocentrotus droeba-chiensis) sea urchin
PublikacjaThe shells from red and green sea urchins accounted for 47.9 and 40.7% of their body weights, respectively. The red and green sea urchin shells contained 91.08 and 90.77% minerals and 4.06 and 4.99% proteins, respectively. The shells did not contain any chitin. Sea urchin shells had a relatively large amount of naphthoquinone pigments, 121 mg per 100 g in red and 163 mg per 100 g in green species. The small quantities of glucosamine...
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The influence of roasting and additional processing on the content of bioactive components in special purpose coffees
PublikacjaCoffee being the beverage consumed worldwide is also a very competitive commodity. Consequently, producers seek ways of attracting consumers by proposing e.g. novel ingredient combinations usually without evaluating their health quality. In this study, variations in health-promoting determinants for five special purpose coffee brews were characterized. The major bioactive components - chlorogenic acids (CAs) - detected by HPLC-DAD-MS...
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An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublikacjaThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
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Sample preparation procedure for the determination of polycyclic aromatic hydrocarbons in petroleum vacuum residue and bitumen
PublikacjaThis paper describes a novel method of samplepreparation for the determination of trace concentrations ofpolycyclic aromatic hydrocarbons (PAHs) in high-boilingpetroleum products. Limits of quantitation of the investigatedPAHs in materials of this type range from tens ofnanograms per kilogram to <20 μg/kg. The studies revealedthat in order to separate most of interferences from theanalytes without a significant loss of PAHs, it...