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Search results for: MASS SPECTROMETRY (MS)
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Nowe metody do badań składników obcych w miodach pszczelich
PublicationPszczoły, zbierając nektar, pyłek kwiatowy i spadź narażone są na częsty kontakt ze szkodliwymi substancjami (stosowanymi w rolnictwie) osadzonymi na roślinach i przenoszą te zanieczyszczenia - na powierzchni ciała lub wraz z pożytkami - do ula, i w konsekwencji zanieczyszczenia przedostają się do miodu.W związku z możliwością zanieczyszczenia miodu przez pestycydy należące do różnych klas związków chemicznych, pomocne okazuje...
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Isolation and structure elucidation of phenolic compounds from Cyclopiasubternata Vogel (honeybush) intact plant and in vitro cultures
PublicationZ materiału roślinnego i hodowli tkankowych Cyclopia subternata Vogel (miodokrzew) wyizolowano i zidentyfikowano matodami NMR i MS 10 związków. m.in. z grupy flawonów i glikozydów izoflawonów. 6 z nich po raz pierwszy wykryto w tym gatunku roślin.
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Advanced Bayesian study on inland navigational risk of remotely controlled autonomous ship
PublicationThe arise of autonomous ships has necessitated the development of new risk assessment techniques and methods. This study proposes a new framework for navigational risk assessment of remotely controlled Maritime Autonomous Surface Ships (MASS). This framework establishes a set of risk influencing factors affecting safety of navigation of a remotely-controlled MASS. Next, model parameters are defined based on the risk factors, and...
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Detekcja obumierania bakterii osadu czynnego
PublicationAnaliza składników głównych (PCA) jest narzędziem służącym wyodrębnieniu podstawowych czynników w rozważanych procesach w oparciu o dostępne pomiary. Zastosowanie PCA w monitorowaniu procesów pozwala na analizę pod kątem diagnostyki nie tylko wielkości mierzonych lecz również wielkości niedostępnych pomiarowo (ograniczenia technologiczne, koszty). Zaleta ta jest szczególnie istotna w przypadku biologicznej oczyszczalni ścieków,...
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Thermal properties of tetrabutylammonium bromotrichloro-, tribromochloro-and tetrabromoferrates(III)
PublicationW pracy badana jest termiczna dekompozycja związków tetrabutylammonium bromotrichloro-, tribromochloro-and tetrabromoferrates(III). Analizę termiczną (TG-MS, DTA, DTG i DSC) prowadzono w atmosferze argonu w zakresie temperatur 293-1073 K. Stałe produkty dekompozycji identyfikowano metodą dyfrakcji promieniowania rentgenowskiego.
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Simplified Distribution Grid Modelling for Connection Analyses
PublicationThis paper considers the modelling of medium and low voltage grids for the purpose of connection studies by distribution grid operators. Possible simplifications in grid modelling are discussed, which are acceptable from the viewpoint of the final result. The main driver of the modelling simplification is the MS Excel environment used as the computation platform, and the limitation of time for grid modelling.
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Experimental analysis of wear resistance of compacts of fine-dispersed iron powder and tungsten monocarbide nanopowder produced by impulse pressing
PublicationThe paper presents the results of studying the structure and wear resistance of compacts produced from fine dispersed reduced iron powder (average particle size 3–mu m) with the addition of tungsten carbide (WC) nanopowder with the average particle size of 25–30 nm. The mass fraction of tungsten carbide (wolfram carbide) in the powder composition was 5% and 10% of the total mass. Impulse pressing was conducted using the modified...
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Raw material influence on volatile composition of agricultural distillates
PublicationCelem prezentowanej pracy było określenie za pomocą techniki HS-SPME/GC-MS charakterystycznych związków markerowych pozwalających na identyfikację pochodzenia surowcowego destylatów rolniczych. Przeprowadzone badania wskazały kilkanaście związków na podstawie obecności których można określić surowiec jakiego użyto przy produkcji destylatu.
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An experimental investigation on the effect of new continuous core-baffle geometry on the mixed convection heat transfer in shell and coil heat exchanger
PublicationIn the article, the authors presented the influence of continuous core-baffle geometry at mixed convection heat transfer in shell and coil heat exchanger. Experiments were carried out for a large power range, i.e. from 100W to 1200W and mass flow rates ranging from 0.01 kg/s to 0.025 kg/s. During the experiments, the mass flow rate of cooling water, the temperature of water at the inlet and outlet as well as the wall temperature...
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Parametric optimization of sandwich composite footbridge with U-shaped cross-section
PublicationParametric optimization of sandwich composite footbridge was presented in the paper. Composite footbridge has 14,5 m long and has U-shaped cross-section with inner dimensions 2,6 × 1,3 m. The sandwich structure in made from GFRP laminate as a faces and PET foam as a core. The aim of analysis was to minimize the mass of the new footbridge that can lead to minimize the cost of structure. After optimization was conducted, the new...
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Investigation on air quality of specific indoor environments—spa salons located in Gdynia, Poland
PublicationDue to excessive application of essential oils and scented products in spa salons during aromatherapy and massage sessions, the elevated concentration of total volatile organic compounds (TVOCs), particularly terpenes, which are known as secondary organic aerosol (SOA) precursors, is expected there. This study was aimed at determination of VOCs with a particular regard to terpenes in air samples collected in selected spa salons...
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Novel decahedral TiO2 photocatalysts modified with Ru or Rh NPs: Insight into the mechanism
PublicationNovel decahedral TiO2 modified with Ru or Rh NPs were successfully synthesized by hydrothermal method. The effect of metal type as well as amount of noble metal precursor (0.05, 0.1, 0.2, 0.3 and 0.5 wt.%) on the photocatalytic activity were investigated. Decahedral TiO2 decorated by Ru and Rh nanoparticles was prepared by photodeposition method, whereas Rh doped TiO2 was obtained by onestep hydrothermal method with introduction...
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Molecular identification and genotyping of Staphylococci: genus, species, strains, colnes, lineages, and interspecies exchanges
PublicationStaphylococci are increasingly recognized as etiological agents of many opportunistic human and animal infections, emphasizing the need for a rapid and accurate identification, even to a genotypical level of these bacteria. In the recent years, there has been a significant progress in typing and phylogenetic study of Staphylococcus species. Here, we describe molecular methods used in taxonomy as well as staphylococci characterization....
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Diamond Nanofilm Normalizes Proliferation and Metabolism in Liver Cancer Cells
PublicationPurpose: Surgical resection of hepatocellular carcinoma can be associated with recurrence resulting from the degeneration of residual volume of the liver. The objective was to assess the possibility of using a biocompatible nanofilm, made of a colloid of diamond nanoparticles (nfND), to fill the side after tumour resection and optimize its contact with proliferating liver cells, minimizing their cancerous transformation. Methods:...
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Anti-cancer effect of Rumex obtusifolius in combination with arginase/nitric oxide synthase inhibitors via downregulation of oxidative stress, inflammation, and polyamine synthesis
PublicationCancer continues to be a leading cause of death worldwide, making the development of new treatment methods crucial in the fight against it. With cancer incidence rates increasing worldwide, ongoing research must focus on identifying new and effective ways to prevent and treat the disease. The combination of herbal extracts with chemotherapeutic agents has gained much interest as a novel strategy to combat cancer. Rumex obtusifolius...
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Solid phase synthesis of conjugates of tuftsin analogues with 1-nitro-acridine derivatives
PublicationZsyntetyzowano na fazie stałej koniugaty 1-nitro-akrydyny z pochodnymi tuftsyny modyfikowanymi na grupie epsilon-aminowej lizyny prostymi aminokwasami, np. alaniną, valiną, beta-alaniną. Końcowe produkty były charakteryzowane za pomocą MS, NMR, analizy elementarnej i przekazane do badań ich aktywności przeciwnowotworowej.
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DYNWIR S-70 program for modal analysis of multisupported and multimass rotors
PublicationThe article provides a brief description of the program Dynwir-S-70 (currently being developed in the Rotor Dynamics and Slide Bearings Department in the Institute of Fluid-Flow Machinery Polish Academy of Sciences in Gdansk) which is a program for analysis of multi-supported and multi-mass rotors. Used algorithms and the construction of mass and stiffness matrix were presented. Damping matrix structure based on Rayleigh damping...
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Ionization and fragmentation of furan molecules by electron collisions
PublicationCation mass spectra obtained by electron impact were measured to investigate the ionization and ionic fragmentation of furan, C4H4O, molecules in the gas phase. The most abundant cations, with comparable intensities in the mass spectra, were the parent, C4H4O+, cation (68 amu) and the C3H3+ fragment (39 amu). The appearance energies of most of the observed ionic fragments were determined and the possible fragmentation processes...
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MONTE CARLO MODELING OF OPTICAL SENSOR FOR POST-OPERATIVE FREE FLAP MONITORING
PublicationAfter a preliminary study of the currently employed methods in vitality monitoring of the tissue flaps (TRAM, DIEP, SIEA), a usefulness of optical techniques is discussed. It seems that one of the most promising in monitoring tissue flaps blood flow is a near infrared spectrometry (NIRS). However, a special design of a measurement sensor has to be developed. First, basing on the literature study an optical “window” is characterized....
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Flow Maps and Flow Patterns of R1233zd(E) in a Circular Minichannel at Low, Medium and High Values of Saturation Pressure
PublicationThere is a gap in knowledge regarding the flow pattern of low-boiling working fluids in the range of high saturation temperatures (above 120°C) and medium and high reduced pressures (0.5-0.9). Data are present in the literature for similar values of reduced pressures, but for lower values of saturation temperature. This is due to the existing refrigeration applications of these working fluids. At high values of reduced pressure,...
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Superhydrophobic sponges based on green deep eutectic solvents for spill oil removal from water
PublicationThe paper described a new method for crude oil-water separation by means of superhydrophobic melamine sponges impregnated by deep eutectic solvents (MS-DES). Due to the numerous potential of two-component DES formation, simple and quick screening of 156 non-ionic deep eutectic solvents using COSMO-RS (Conductor-like Screening Model for Real Solvents) computational model was used. DES which were characterized by high solubility...
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Synthesis of linear tuftsin analogues modified at the epsilon-amino group of lysine
PublicationZsyntetyzowano na fazie stałej nowe analogi tuftsyny i retro-tuftsyny zawierające wiązanie isopeptydowe na epsilon-aminowej grupie lizyny jako potencjalne immunostymulatory. Do syntezy wykorzystano standardową procedurę Fmoc. Po zdjęciu osłon kwasem TFA końcowe związki były oczyszczane, liofilizowane i charakteryzowane: MS, HPLC i NMR.
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Spinning Fluids Reactor: A new design of a gas – liquid contactor
PublicationCurrent trends in chemical reactor design are based on adapting these to the requirements of a particular chemical process. Processes involving reactions between the gas and liquid phase in particular require precise adjustment of all parameters. The common denominator for most modern design solutions is enhancement of the mass transfer area and the overall volumetric mass transfer coefficient. Gas – liquid contactors evolved from...
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Structure analysis and thermal degradation characteristics of bio-based poly(propylene succinate)s obtained by using different catalyst amounts
PublicationLinear bio-based polyester polyols were prepared with the use of succinic acid and 1.3-propanediol (both with natural origin). As a catalyst was used tetraisopropyl orthotitanate (TPT). In order to determine the effect of various catalyst content on the thermal degradation characteristics, three different TPT amounts, as a 1.3-propanediol equivalent, were used, namely 0.1 mass% (PPS-0.1), 0.2 mass% (PPS-0.2) and 0.25 mass% (PPS-0.25)....
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Wpływ sposobu odwzorowania pojazdu szynowego na odpowiedź dynamiczną przęsła mostowego
PublicationW pracy przedstawiono rezultaty analiz numerycznych oraz badań eksploatacyjnych dwóch przęseł mostowych wymuszonych ruchomym pojazdem szynowym. Pojazd odwzorowano za pomocą czterech modeli uproszczonych: strumienia sił skupionych, strumienia mas skupionych oraz strumieni oscylatorów jedno- i dwumasowych. Analizy numeryczne wykonano przy wykorzystaniu MES. Potrzebne parametry dynamiczne wyznaczono na podstawie wyników identyfikacji...
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Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
PublicationDynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation...
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Isotope shifts of multipole lines of Pb I and Pb II
PublicationStudies of isotope shifts of three multipole lines between levels of the ground configuration 6s26p2 of Pb I, i.e.: 461.9 nm(1S0→3P1), 531.5 nm(1S0→3P2) and 733.2 nm(1D2→3P1), as well as 710.2 nm line (6s26p2P3∕2→6s26p2P1∕2) of Pb II are presented. We determined the isotope shifts between four stable isotopes: 204, 206, 207, 208. By the use of King plot analysis we were able to separate the mass and the field shifts. We found that...
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Dissociation of furan-2-carboxylic acid by low energy electrons
PublicationElectron attachment to molecular target can lead to a variety of negative fragment ions. We experi- mentally probe the main dissociative electron attachment channels in furan-2-carboxylic acid (C3H3O2 − COOH) - a molecular target composed of two important structural units: a furan ring and a carboxylic group. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV. Our detection setup...
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Methodological advances for selenium speciation analysis in yeast.
PublicationPrzedstawiono nowe zaawansowane metody specjacji selenu w dodatkach spożywczych. Szczególną uwagę zwrócono na przygotowanie próbek odnośnie: frakcjonowania różnych klas związków tworzonych przez selen, rozdzielanie wodnych ekstraktów za pomocą chromatografii wykluczeniowej oraz charakteryzowania rozpuszczalnych w wodzie frakcji proteinowych przy użyciu detektorów MALDI oraz TOF-MS.
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A novel nucleotide found in human erythrocytes, 4-pyridone-3-carboxamide-1-beta-D-ribonucleoside triphosphate
PublicationZidentyfikowano nowy, nieznany nukleotyd, występujący w erytrocytach osób chorych na przewlekłą niewydolność nerek, w stężeniu porównywalnym do zawartości ATP. Nukleotyd ten wyizolowano chromatograficznie, a jego strukturę określono jako trójfosforan 4-piridono-3-karboksyamido-1-b-D-rybonukleozydu, na podstawie danych spektralnych UV, MS, IR i NMR.
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Channel Blockage and Flow Maldistribution during Unsteady Flow in a Model Microchannel Plate heat Exchanger
PublicationThis paper describes the problem of channel blockage as a result of flow maldistribution between the channels of a model mini channel plate heat exchanger consisting of one pass on each leg. Each leg of the heat exchanger contains 51 parallel and rectangular minichannels of four hydraulic diameters namely 461 μm, 571 μm, 750 μm and 823 μm. In addition, a more complex geometry has been investigated where for the sake of breaking...
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Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate
PublicationDegradation of pentoxifylline (PTX) by sodium peroxydisulfate (SPDS) assisted by UV irradiation has been investigated in deionized water. The treatment was more favorable over direct photolysis or peroxydisulfate oxidation alone. The effects of various parameters, including different dosage of oxidant agent, PTX concentration, initial solution pH levels, and the presence of inorganic ions like chloride, nitrate and carbonate have...
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Chapter 13. Immunological determination of the pharmaceutical diclofenac in environmental and biological samples
PublicationOpracowano wysoce specyficzną i czułą metodę immunologiczną oznaczania przeciwzapalnego leku diklofenaku. Jest to jeden z najczęściej wykrywanych farmaceutyków w środowisku. Granicę wykrywalności oraz wartość IC50 określono na poziomie 6 ng/L oraz 60 ng/L dla wody wodociągowej, odpowiednio. W badaniu porównawczym, stosując test ELISA oraz GC-MS określono poziomy stężeń diklofenaku w wodach ściekowych z 21 oczyszczalni ścieków i...
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Biomass estimation using a length-weight relationship in beetle larvae (Coleoptera: Aphodiidae, Histeridae, Hydrophilidae, Staphylinidae) obtained from cow dung
PublicationThis research enabled the relationship between length and dry body mass to be determined for 158 beetle larvaetaken from cow dung in north-eastern Poland. The larvae were divided into three morphological types, for which the power and linear function of the body length-weight relationship were determined. The linear regression equation characterizes the relationship between body weight and...
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Evaluation of the Greenness of Analytical Procedures
PublicationThis contributions introduces the need to develop the methods to evaluate analytical procedures in the light of green analytical chemistry. Green chemistry metrics are not applicable in analytical chemistry because they refer to the mass of product and no product with mass is generated during analytical determination. Analytical greenness evaluations are based on scoring - such as NEMI or Eco-scale or comparative analysis as it...
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SYNTHESIS OF PHOSPHORUS TACRINE ANALOGUES AS A NEW POTENTIAL ANTI-ALZHEIMER’S DISEASE AGENTS
PublicationA series of novel phosphorus tacrine derivatives was obtained in three steps, including synthesis of 9-chlorotacrine, connection of 9-chlorotacrine with hexamethylenediamine, 1,8-diaminooctane and 1,12-diaminododecane linkers and reaction of obtained tacrine diamine analogues with corresponding acid ester to give nine tacrine organophosphorus compounds. All of the obtained final structures were characterized by 1H NMR, 13C NMR,...
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Thermal analysis of manganese(II) complexes of general formula(Et4N)2[MnBrnCl4−n]
PublicationBadano termiczną dekompozycję związków zawierających aniony [MnBrnCl4−n]2− (n = 0-4) i kation tetraetylammonium. Wykorzystywano metody DSC i TG. Badania prowadzono w atmosferze argonu w temperaturze 173-500K (DSC)i 300-1073K (TG). Produkty dekompozycji określono za pomocą MS, FTIR, Far-FTIR i dyfraktometrii rentgenowskiej.
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Identification of plate dynamic parameters for structural health monitoring
PublicationPraca przedstawia technikę wyznaczania parametrów modalnych wykorzystywanych w diagnostyce konstrukcji. Modalna masa, sztywność, tłumienie i postacie drgań wyznaczone są dla prostokątnej stalowej płyty na podstawie badań eksperymentalnych. Teoretyczne parametry modalne otrzymaneo z modelu MES. Omówiony został wpływ dodatkowej masy na parametry modalne konstrukcji.This paper presents a technique for modal parameters estimation for...
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Maximum transportation growth in energy and solute particles in Prandtl martial across a vertical 3D-heated surface: Simulations achieved using by finite element approach
PublicationThe goal of this study is to determine the maximum energy and solute particles' transportation growth in a 3D-heated region of Prandtl martial through a dynamic magnetic field. The effects of this field on the properties of solvent molecules and heat conduction are studied. A correctly stated functional method and a finite element approach are comparable to a certain type of differential equations. In order demonstrate the effects...
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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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Interspecific distribution and co-associations of chemical elements in the liver tissue of marine mammals from the Polish Economical Exclusive Zone, Baltic Sea
PublicationPrzeprowadzono analizy próbek wątroby ssaków morskich z Polskiej Strefy Ekonomicznej Morza Bałtyckiego w celu oznaczenia szerokiej gamy pierwiastków (mikro- i makroelementy) z wykorzystaniem takich technik analitycznych jak ICP-MS, ICP-AES oraz CV-AAS.Badano zależności pomiędzy zawartością poszczególnych pierwiastków a wiekiem, płcią, miejscem bytowania, sposobem odżywiania i gatunkiem ssaków.
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Analytical procedure for the determination of chlorobenzenes in sediments
PublicationW pracy przedstawiono badania nad opracowaniem procedury oznaczania chlorobenzenów w próbkach osadów dennych. Składa się ona z następujących etapów: ekstrakcji za pomocą rozpuszczalnika (wytrząsanie); oczyszczanie ekstraktu; odparowanie rozpuszczalnika (redukcja objętości ekstraktu); analiza z wykorzystaniem techniki GC-MS. Przeprowadzono badania stopnia odzysku z wykorzystaniem wzorca wewnętrznego (deuterowany 1,2-dibromobenzen).
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Isolation of xanthone and benzophenone derivatives from Cyclopia genistoides (L.) Vent. (honeybush) and their pro-apoptotic activity on synoviocytes from patients with rheumatoid arthritis
PublicationA fast and efficient method for the isolation of the C-glucosidated xanthones mangiferin and isomangiferin from the South-African plant Cyclopia genistoides was developed for the first time. Two benzophenone derivatives: 3-C-β-glucosides of maclurin and iriflophenone, were isolated from C. genistoides extracts using semi-preparative. The structures of the compounds were determined by 1D and 2D NMR experiments and/or LC-DAD-ESI–MS.
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublicationThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
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Chemical and biological stability of polyene macrolides
PublicationThe polyene macrolide antibiotics have been used in an-tifungal therapy since first o f them were discovered in 1950's. Up to now, four polyene macrolides are being used in medical practice, namely amphotericin B, nystatin, candi-cidin and pimaricin.The antifungal activity and mode of ac-tion of polyene macrolides is determined by their structure, chemical and physical properties.The main fragment of polyene...
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Interspecific and intraspecific variation in organochlorine pesticides and polychlorinated biphenyls using non-destructive samples from Pygoscelis penguins
PublicationAs humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where...
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Use of response surface methodology in characterization of properties of recycled high density polyethylene/ground tire rubber compositions
PublicationSearching for newways to utilize rubber and polymerwaste has been the focus of many studies conducted by research centers and companies worldwide. In this study, the influence of extrusion conditions on the properties of thermoplastic compositions containing post-production recycled high density polyethylene (PE-HD) and ground tire rubber (GTR) at 50:50 mass ratiowas examined. Response Surface Methodology (RSM) was used to determine...
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A risk comparison framework for autonomous ships navigation
PublicationMaritime autonomous surface ships (MASS) may operate in three predefined operational modes (OM): manual, remote, or autonomous control. Determining the appropriate OM for MASS is important for operators and competent authorities that monitor and regulate maritime traffic in given areas. However, a science-based approach to this respect is currently unavailable. To assist the selection of the proper OM, this study presents a risk-based...
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Organic and conventional kiwifruit myths versus reality: antioxidant, antiproliferative and health effects
PublicationComparison between organic and conventional kiwifruit cultivars ''Hayward'' and ''Bidan'', which was done by four redical scavenging assays, ESI-MS, and DSC measurements, showed significant differences between 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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Balance error generated by numerical diffusion in the solution of Muskingum equation
PublicationIn the paper the conservative properties of the lumped hydrological models with variable parameters are discussed. It is shown that in the case of the non-linear Muskingum equation the mass balance is not satisfied. The study indicates that the mass balance errors are caused by the improper form of equation and by the numerical diffusion which is generated in the solution. It has been shown that the classical way of derivation...