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Search results for: DLLME-GC-MS
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Chromatographic and Spectroscopic Identification and Recognition of Natural Dyes, Uncommon Dyestuff Components, and Mordants: Case Study of a 16th Century Carpet with Chintamani Motifs
PublicationA multi-tool analytical practice was used for the characterisation of a 16th century carpet manufactured in Cairo. A mild extraction method with hydrofluoric acid has been evaluated in order to isolate intact flavonoids and their glycosides, anthraquinones, tannins, and indigoids from fibre samples. High-performance liquid chromatography coupled to spectroscopic and mass spectrometric detectors was used for the identification of...
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Microstructure and mechanical properties of laser surface-treated Ti13nb13zr alloy with MWCNTs coatings
PublicationLaser surface modification of titanium alloys is one of the main methods of improving the properties of titanium alloys used in implantology. This study investigates the microstructural morphology of a laser-modified surface layer on a Ti13Nb13Zr alloy with and without a carbon nanotube coating deposited by electrophoretic deposition. Laser modification was performed for samples with and without carbon nanotube coating for two...
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Projektowanie wiedzy. Relacyjne bazy danych (ISBN 978-83-7348-702-4)
PublicationZałożeniem podręcznika Projektowanie wiedzy – relacyjne bazy danych jest kształtowanie praktycznych umiejętności opartych na wiedzy z zakresu tworzenia relacyjnych baz danych z wykorzystaniem narzędzi Microsoft Access. Książka zawiera zestawy ćwiczeń i zadań wraz z rozwiązaniami, które umożliwiają skuteczną naukę prawidłowego tworzenia modelu danych. Opracowanie wyróżnia się na tle innych prac bardzo szczegółowym i dokładnym...
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The influence of thermal conditions on V2O5 nanostructures prepared by sol-gel method
PublicationThis work presents the result of structure investigations ofV 2O5 nanorods grown from thin films and powders prepared by sol-gel method. To examine the best temperature of nanorods crystallization, thin films deposited by spin-coating method on quartz glass or silicon substrates and bulk xerogel powders were annealed at various temperatures ranging from 100∘C to 600∘C. The structure of the samples was characterized by X-ray diffraction...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublicationThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Recent Developments in Data-Assisted Modeling of Flexible Proteins
PublicationMany proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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5-Bromo-2′-deoxycytidine—a potential DNA photosensitizer
PublicationA double-stranded oligonucleotide, 80 base pairs in length, was multiply labeled with 5-bromo-2′-deoxycytidine (BrdC) using polymerase chain reaction (PCR). The modified oligonucleotide was irradiated with 300 nm photons and its damage was assayed by employing DHPLC, LC-MS and denaturing polyacrylamide gel electrophoresis (PAGE). Two types of damage were demonstrated, namely, single strand breaks (SSBs) and intrastrand cross-links...
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Spectroscopic and cytotoxic characteristics of (p-cymene)Ru(II) complexes with bidentate coumarins and density functional theory comparison with selected Pd(II) complexes
PublicationThis paper presents the synthesis of two new (p-cymene)-ruthenium(II) complexes with the bidentate coumarin ligands. Both complexes were characterized by FTIR spectroscopy, 1H NMR, 13C NMR, MS, elemental analysis and DFT calculations. The X-ray structure of complex 3a was also solved. The cytotoxic properties of both complexes were examined on human leukemia NALM-6 and HL-60 cells and melanoma WM-115 cells. The complexes possess...
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Comparison of oxidative stability of different edible oils
PublicationCelem prezentowanych badań było porównanie stabilności oksydacyjnej olejów roślinnych z Polski, Finlandii i Hiszpanii. Na etapie przyspieszania utleniania zastosowano promieniowanie ultrafioletowe (UV). Po naświetlaniu olejów powstałe związki lotne ekstrahowano z fazy nadpowierzchniowej za pomocą techniki mikroekstrakcji do fazy stacjonarnej (HS-SPME) i analizowano z zastosowaniem chromatografu gazowego z detektorem płomieniowo-jonizacyjnym...
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Studies on applicability of new solid-phase microextraction fibers for the selective extraction and determination of short - chain monocarboksylic acids
PublicationShort-chain monocarobxylic acids, sometimes referred to as volatile fatty acids (VFA), are a group of low molecular weight alkyl monocarboxylic acids that are widely distributed within the environment. These molecules contain any from 2 to 8 carbon atoms and originate from the anaerobic biodegradation of organic matter such as carbohydrates, proteins, and fats. These compounds are commonly found in the effluents from animal farming,...
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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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Novel analytical method for detection of orange juice adulteration based on ultra-fast gas chromatography
PublicationThe food authenticity assessment is an increasingly important issue in food quality and safety. The application of an electronic nose based on ultra-fast gas chromatography technique enables rapid analysis of the volatile compounds from food samples. Due to the fact that this technique provides chemical profiling of natural products, it can be a powerful tool for authentication in combination with chemometrics. In this article,...
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Mass spectrometry based identification of geometric isomers during metabolic stability study of a new cytotoxic sulfonamide derivatives supported by quantitative structure-retention relationships
PublicationA set of 15 new sulphonamide derivatives, presenting antitumor activity have been subjected to a metabolic stability study. The results showed that besides products of biotransformation, some additional peaks occurred in chromatograms. Tandem mass spectrometry revealed the same mass and fragmentation pathway, suggesting that geometric isomerization occurred. Thus, to support this hypothesis, quantitative structure-retention relationships...
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Model opisu wydajności protokołu SIP dla VoIP
PublicationCoraz większa popularność protokołu SIP (Session Initiation Protocol) pociąga za sobą konieczność wymiarowania zasobów sieciowych i badania wydajności samego protokołu z uwagi na potrzebę gwarancji poziomu i jakości usług. Dla realizacji tego celu prowadzi się szereg prac badawczych i niniejsza publikacja jest zreferowaniem wyników takich prac badawczych wykonanych przez autorów. Dotyczą one modelu analitycznego dla opisu poziomu...
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Glucosinolates from lepidium peruvianum as potential antiamnestic drugs
PublicationLepidium peruvianum (maca) (Brassicaceae) is a naturally occurring plant mainly in the high Andes of Peru. In recent years, it has been intensively researched in terms of its influence on various diseases and towards health improvement. Alzheimer’s disease is an incurable disease that most often affects adults over the age of 60. As since 2003 the US Food and Drug Administration (FDA) did not approve any new drug for Alzheimer’s...
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Application of the neural networks for developing new parametrization of the Tersoff potential for carbon
PublicationPenta-graphene (PG) is a 2D carbon allotrope composed of a layer of pentagons having sp2- and sp3-bonded carbon atoms. A study carried out in 2018 has shown that the parameterization of the Tersoff potential proposed in 2005 by Ehrhart and Able (T05 potential) performs better than other potentials available for carbon, being able to reproduce structural and mechanical properties of the PG. In this work, we tried to improve the...
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Fatal N-Ethylhexedrone Intoxication
PublicationN-Ethylhexedrone [2-(ethyloamino)-1-phenylhexan-1-one; α-ethylaminohexanophenone; NEH] is one of the most recent synthetic cathinones that appeared on the illegal market in late 2015. The majority of information concerning the model of consumption of NEH and its impact on the body originates only from self-reports from grey literature websites and drug forums. There are only limited data associated with the concentrations of NEH...
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5-Thiocyanato-2′-deoxyuridine as a possible radiosensitizer: electron-induced formation of uracil-C5-thiyl radical and its dimerization
PublicationIn this work, we have synthesized 5-thiocyanato-2′-deoxyuridine (SCNdU) along with the C6-deuterated nucleobase 5-thiocyanatouracil (6-D-SCNU) and studied their reactions with radiation-produced electrons. ESR spectra in γ-irradiated nitrogen-saturated frozen homogeneous solutions (7.5 M LiCl in H2O or D2O) of these compounds show that electron-induced S–CN bond cleavage occurs to form a thiyl radical (dU-5-S˙ or 6-D-U-5-S˙) and...
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On the fast BSS transition algorithms in the IEEE 802.11r local area wireless networks
PublicationHandover 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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Lightning impulse efficiency of horizontal earthings
PublicationSystem 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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Photodegradation of phenol by UV/TiO2 and Vis/N,C-TiO2 processes: Comparative mechanistic and kinetic studies
PublicationPorównano drogę fotodegradacji w dwóch systemach badawczych: UV/TiO2 i Vis/N,C-TiO2. Zbadano efektywność degradacji fenolu, powstające produkty pośrednie oraz generowanie rodników hydoksylowych w przygotowanych układach badawczych. Wyniki badań wykazały porównywalne efektywności degradacji fenolu w zawiesinach: domieszkowany TiO2/Vis i TiO2 P-25/UV. Uzyskane wyniki wskazują również na odmienne drogi degradacji zanieczyszczeń w...
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Characterization of Rapana thomasiana as an indication of environmental quality of the Black Sea coast og Bulgaria
PublicationW pracy przedstawiono wyniki badań próbek mięczaków morskich (brzuchonogów) na zawartość takich składników jak wielopierścieniowe węglowodory aromatyczne, polichlorowane bifenyle, mikroelementy tych składników oraz aktywność biologiczną. Oceniono różnice w zawartości tych składników w próbkach uzyskanych z tych mięczaków morskich zebranych na obszarach niezanieczyszczonych i obszarach charakteryzujących się dużą intensywnością...
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Organic and conventional kiwifruit, myths versus reality: antioxidant, antiproliferative and helth effects
PublicationComparison 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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Ograniczniki bezpiecznikowe prądów zwarciowych na duże prądy robocze.
PublicationPrzedstawia się ogólną ideę ograniczania prądów zwarciowych w obwodach o dużych prądach roboczych niskiego i średniego napięcia w oparciu o bezstykowe hybrydowe ograniczniki prądu z wykorzystaniem specjalnych, krótkotopikowych bezpieczników. Idea takich ograniczników polega na zastąpieniu łącznika zestykowego ogranicznika hybrydowego bezpiecznikiem o minimalnej długości topika z intensywnym chłodzeniem topika przez osiowe przewodnictwo...
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Effect of austempering temperature on microstructure and cyclic deformation behaviour of multiphase low-carbon steel
PublicationThis paper examined the cyclic deformation behaviour of multiphase low-carbon steel that was subjected to austempering heat treatments at four temperatures (190 °C, 230 °C, 275 °C, and 315 °C) below the martensite start temperature (Ms = 353 °C). The tests were conducted at room temperature, under fully reversed strain-controlled conditions, with strain amplitudes in the range 0.5–1.0%. The microstructure was observed by transmission...
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Analysis of volatile fraction of sweetie (Citrus maxima × Citrus paradisi) and its parent fruit using proton transfer reaction mass spectrometry
PublicationThe quality of the fruit is affected by several main ingredients and the aroma plays a fundamental role during the selection of fruit by consumers. In the case where several fruit have similar aromas and only one of them has specific health properties, it is very important to find the differences in the volatile organic compounds (VOCs) composition to distinguish these samples. Such situations are often found for hybrid fruit....
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Influence of Diosmin Treatment on the Level of Oxidative Stress Markers in Patients with Chronic Venous Insufficiency
PublicationOxidative stress plays an important role in the pathophysiology of many human disorders, while antioxidants prevent the development of various adverse symptoms. Diosmin is a natural flavonoid applied in vascular system disorders, especially in chronic venous insufficiency (CVI), and it plays a significant part in the alleviation of CVI symptoms. Due to antioxidant activity, it also has the ability to scavenge the oxygen free radicals...
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Influence of passive house technology on time and cost of construction investment
PublicationDue to the changes in the energy standards for housing in Poland there are many concerns. Is the standard required by the regulation achievable and if it is, then at what cost? There are many solutions to construct a building in line with the requirements of passive house technology. They are differentiated by price and time required for implementation. This study is based on the solution proposed by one of Polish companies, offering...
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X-ray and UV Radiation Damage of dsDNA/Protein Complexes
PublicationRadiation and photodynamic therapies are used for cancer treatment by targeting DNA. However, efficiency is limited due to physico-chemical processes and the insensitivity of native nucleobases to damage. Thus, incorporation of radio- and photosensitizers into these therapies should increase both efficacy and the yield of DNA damage. To date, studies of sensitization processes have been performed on simple model systems, e.g.,...
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Interaction of human serum albumin with volatiles and polyphenols from some berries
PublicationHeadspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GC GCeTOFMS) identified 19 and quantified 6 monoterpenes in gooseberries, blueberries and cranberries. As a protein model human serum albumin (HSA) was used in interaction with terpenes. Specific binding of terpenes to HSA under the physiological conditions was a result of the formation...
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Chemical Composition of Atmospheric Air in Nemoral Scots Pine Forests and Submountainous Beech Forests: The Potential Region for the Introduction of Forest Therapy
PublicationStudies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples...
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Measurements of the rms currents in two phases in a ship power station with two generators operating in parallel
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the rms...
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Heart rate PPG signals with acceleration captured at wrist during small and moderate body movements
Open Research DataHeart rate PPG signals with acceleration captured at wrist during small and moderate body movements
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Measurements of the fundamental harmonic frequency of voltages on main bars in a ship power station
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the fundamental...
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Measurements of the rms voltages on main bars in a ship power station with two generators operating in parallel
Open Research DataThe presented dataset is part of research focusing on the assessment of metrological properties of the instrument, Estimator/Analyzer (E/A v.2), developed and made at the Faculty of Electrical Engineering, Department of Marine Electrical Power Engineering of Gdynia Maritime University. The attached dataset contains processed data, expressing the rms...
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Dydaktyczne Piątki – 19.01.2024
EventsProwadząca: Grażyna Knitter, PG Nagrania z poprzednich spotkań online znajdziesz na kanale YouTube CNE PG.
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Dydaktyczne Piątki – 12.01.2024
EventsProwadząca: Joanna Mytnik, PG Nagrania z poprzednich spotkań online znajdziesz na kanale YouTube CNE PG.
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Dydaktyczne Piątki. Edukacja – interakcja
EventsProwadząca: Anna Turula (UKEN Kraków) Nagrania z poprzednich spotkań online można znaleźć na kanale YouTube CNE PG.
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Novel Resveratrol-Based Substrates for Human Hepatic, Renal, and Intestinal UDP-Glucuronosyltransferases
PublicationTrans-Resveratrol (tRes) has been shown to have powerful antioxidant, anti-inflammatory, anti-carcinogenic, and anti-aging properties; however, its use as a therapeutic agent is limited by its rapid metabolism into its conjugated forms by UDP-Glucuronosyltransferases (UGTs). The aim of the current study was to test the hypothesis that the limited bioavailability of tRes can be improved by modifying its structure to create analogs...
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Determination of volatile organic compounds in water samples using membrane-solid phase microextraction (M-SPME) (headspace version)
PublicationThe results of a study on the use of membrane-solid phase microextraction (M-SPME) for sampling volatile organic compounds (VOCs) from the headspace above the liquid medium are presented. The sampled VOCs were subsequently quantified by gas chromatography (GC). Two systems were compared in this study, i.e. a novel two-phase sorption system (M-SPME), and a commercial fibre. Headspace sampling using SPME was optimized with respect...
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Dydaktyczne Piątki. Aktywny wykład: strategie pracy.
EventsProwadząca: Joanna Mytnik (Centrum Nowoczesnej Edukacji PG) Nagrania z poprzednich spotkań online znajdziesz na kanale YouTube CNE PG.
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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
PublicationThis 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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Development of chromatographic and mass spectrometry conditions for untargeted lipidomic analysis of human breast milk
PublicationHuman breast milk (HBM) is a complex biofluid containing components which are essential for the proper growth of the newborn (for example nutrients such as carbohydrates, proteins, lipids) and also bioactive substances. According to the literature, most of studies involving HBM nutrients investigations focused essentially on the determination of proteins. The molecular composition of lipids in HBM is not well known as the protein...
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Oddziaływanie przepięć atmosferycznych na bezpieczniki SN: badania wstępne
PublicationObserwowane 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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In search of molecular precursors for cadmium sulfide-new complexes with a sulfur-rich kernel: cadmium(II) tri-tert-butoxysilanethiolates with additional diethyldithiocarbamato ligand
PublicationW 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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Inactivation of glucosamine-6-phosphate synthase by N3-oxoacyl derivatives of L-2,3-diaminopropanoic acid
PublicationN3-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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Chemical composition, antioxidant and anticancer effects of the seeds and leaves and indigo (polygonum tinctorium Ait.) Plant
PublicationSeeds 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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The structure of levorin A3, a minor component of levorin complex
PublicationBudowa 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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Improvements and new functionalities of UNRES server for coarse-grained modeling of protein structure, dynamics, and interactions
PublicationIn 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...