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Analysis of floor-to-column pounding of buildings founded on different soil types
PublicationThe aim of this study is to investigate the effect of the soil type on buildings experiencing floor-to-column pounding during earthquakes. Five buildings with 4-storeys, 6-storeys, and 7-storeys were considered. Three types of the 4-storey building with different total heights were taken into account which leads to floor-to-column pounding at 1/3, 1/2 and 2/3 of the height of the impacted column. Two pounding scenarios were considered,...
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Buckling and post-buckling behavior of column with central non-linear restraint
PublicationW pracy bada się wyboczenie giętne i zachowanie pokrytyczne ściskanego osiowo pręta z nieliniową sprężystą podporą w środku rozpiętości przęsła. Rozwiązanie problemu wyznaczono za pomocą metody małego parametru. Podano przykład numeryczny wyboczenia i zachowania pokrytycznego swobodnie podpartego pręta z nieliniową sprężytą podporą w środku rozpiętości. Wykazano istotny wpływ nieliniowości podpory na zachowanie pokrytyczne pręta.
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublicationThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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Sample preparation and chromatographic analysis of acidic herbicides in soils and sediments
PublicationW pracy przedstawiono różne techniki przygotowania próbek i oznaczania herbicydów z grupy pochodnych fenoli i pochodnych kwasów karboksylowych w próbkach gleby. Opisano wybrane metody wzbogacania i izolacji analitów, m. in.: ekstrakcję za pomocą wodnych roztworów zasad i rozpuszczalników organicznych płynem w stanie nadkrytycznym, wodą w stanie podkrytycznym, cieczą pod zwiększonym ciśnieniem, cieczą wspomaganą mikrofalami. Niski...
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Chromatographic Examinations of Tea's Protection Against Lipid Oxidative Modifications
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Quantitative structure-(chromatographic) retention relationship models for dissociating compounds
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TS-based RSM-aided design of cold-formed steel stiffened C-sectional columns susceptible to buckling
PublicationThe paper focuses on joint-performance analysis of a built-up cold-formed thin-walled C-sectional column with a fillister (stiffener) of the same type, interconnected with a series of bolts located along the length of the compressed members in specific spacing. The quantity of bolts and the non-connected starting distance of the fillister are considered random variables of the problem. Optimal distribution of joints on the stiffener...
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Study on deformed steel columns subjected to impact load due to soft-storey failure in buildings during earthquakes
PublicationThe so called soft-storey failure is one of the most typical types of damage induced in buildings as the result of earthquake excitation. It has been observed during ground motions that the failure of an upper soft storey of a structure results in large vertical impact load acting on the lower floors. If the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of...
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Application of linear buckling sensitivity analysis to economic design of cylindrical steel silos composed of corrugated sheets and columns
PublicationThe paper deals with global stability of steel cylindrical silos composed of corrugated walls and vertical columns with loads imposed by a bulk solid following Eurocode 1. The optimum silo design with respect to the steel weight was based on a sensitivity analysis method. The changes of silo column profiles at each design step were performed by means of influence lines for the buckling load factor due to the unit column bending...
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Gas chromatography-olfactometry of alcoholic beverages
PublicationW rozdziale 5 książki przedstawiono zastosowanie techniki chromatografia gazowa-olfaktometria (GC-O)w ustalaniu zależności między zapachem a składem chemicznym lotnej frakcji napojów alkoholowych. W pierwszej części przedstawiono zasadę techniki GC-O, procedury przygotowania próbek do analizy, metody zbierania danych oraz warunki analizy. Następnie omówiono zastosowanie techniki GC-O w analizie i ocenie jakości różnych napojów...
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Decomposing Cavities in Digital Volumes into Products of Cycles
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Opracowanie optymalnych warunków rozdzielania i identyfikacji metabolitów ro lin z rodzaju droseraceae, z zastosowaniem wysokosprawnej kolumnowej chromatografii cieczowej= A research on the composition of eluent for separation of plant metabolites by column reversed phase liquid chromatography
PublicationOd kilku lat na świecie trwają badania składników roślin owadożernych wykazujących atrakcyjne właściwości biologicznie czynne, tj. działanie przeciwbakteryjne, przeciwgrzybowe, antyoksydacyjne, a być może, także, przeciwnowotworowe. Pozyskiwanie substancji biologicznieaktywnych z materiału naturalnego, na drodze hodowli in vitro a następnie ekstrakcji i rozdzielania jest bardziej korzystne pod względem ekonomicznym, niż ich wytwarzanie...
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Application of normal-phase high-performance liquid chromatography followed by gas chromatography for analytics of diesel fuel additives
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Application of normal-phase high-performance liquid chromatography followed by gas chromatography for analytics of diesel fuel additives
PublicationThe paper presents the results of investigations on new procedures of determination of selected cleaning additives in diesel fuel. Two procedures: one-step analysis using gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS) and a two-step procedure in which normal-phase high-performance liquid chromatography (NP-HPLC) was used for preliminary separation of the additives, were compared. The additive...
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Experimental Study and Finite Element Modeling of Reinforced Concrete Column Having an Opening
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Effects of Column Base Flexibility on Seismic Response of Steel Moment-Frame Buildings
PublicationSteel Moment Resisting Frames (SMRFs) are very popular lateral load resisting systems in many seismically active regions. However, their seismic response is strongly dependent on the rotational fixity of column base connections. Despite many studies (both experimental and numerical) in this particular area, available approaches for estimating column base flexibility have been validated only against laboratory test data. In the...
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Analysis of the Hydrodynamic Properties of the 3-Column Spar Platform for Offshore Wind Turbines
PublicationThe article presents a design of a floating platform for offshore wind turbines. The concept is a modification of the Spar design and consists of three variable section columns connected to each other by a ballast tank in the lower part of the platform. This solution makes it possible to influence the position of the centre of buoyancy and the centre of mass of the structure. Compared to the classic Spar platform structure, the...
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Column base fixity in steel moment frames: Observations from instrumented buildings
PublicationThe rotational fixity of column base connections in Steel Moment Resisting Frames (SMRFs) strongly influences their seismic response. However, approaches for estimating base fixity have been validated only against laboratory test data. These approaches are examined based on strong motion recordings from four instrumented SMRF buildings in California to informbest practices for seismic response simulation. These buildings represent...
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Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC
PublicationReverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery...
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Stability of cylindrical steel silos composed of corrugated sheets and columns based on FE analyses versus Eurocode 3 approach
PublicationComprehensive static and dynamic 3D stability finite element analyses of a cylindrical steel silo composed of corrugated sheets and open thin-walled vertical stiffener profiles were carried out by taking the geometric and material non-linearity into account. The silowas subjected to axisymmetric and non-axisymmetric loads imposed by a bulk solid following Eurocode 1. Theoretical and measured initial geometric imperfections were...
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Determination of buckling strength of silos composed of corrugated walls and thin-walled-columns using simplified wall segment models
PublicationW artykule przedstawiono wyniki obszernych analiz numerycznych wyboczenia i stateczności metalowych silosów z blachy falistej wzmocnionych cienkościennymi słupami. Wykonano analizy liniowe i nieliniowe. Do obliczeń zaproponowano proste modele segmentów ścian zamiast skomplikowanych modeli całych silosów. Otrzymano bardzo dobrą zgodność wyników numerycznych. Wyniki obliczeń numerycznych porównano dodatkowo z wynikami normowymi.
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Some remarks on gas chromatographic challenges in the context of green analytical chemistry
PublicationOmówiono możliwości wprowadzenia zasad zielonej chemii analitycznej w odniesieniu do technik chromatograficznych.
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Preparation of environmental samples for gas chromatographic determination of selected organic pollutants
PublicationOpisano różne metody izolacji i wzbogacania zanieczyszczeń organicznych z ciekłych, gazowych i stałych próbek środowiskowych. Opisano konstrukcję i testowanie nowych systemów do przygotowania próbek oraz ich zastosowanie w połączeniu z chromatografią gazową do oznaczania zanieczyszczeń organicznych w póbkach rzeczywistych.
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Derivatisation in gas chromatographic determination of acidic herbicides inaqueous environmental samples.
PublicationW pracy przedstawiono przegląd literaturowy dotyczący wykorzystania derywatyzacji w oznaczaniu herbicydów kwasowych w wodnych próbkach środowiskowych za pomocą chromatografii gazowej. Omówiono główne typy reakcji (transestryfikacja, estryfikacja, sililowanie, alkilacja, alkilacja ekstraktywna i pirolityczna), które powodują utworzenie pochodnych, łatwych do analizy techniką chromatografii gazowej. Scharakteryzowano także...
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Determination of estrogenic endocrine disruptors in environmental samples - a review of chromatographic methods
PublicationWśród związków endokrynnych to estrogeny zarówno naturalne jak i syntetyczne zostały wskazane i opisane jako związki niosące ze sobą największy potencjał aktywności estrogennej. Wysoki potencjał estrogenny jaki posiadają związki z grupy hormonów płciowych potwierdziły badania przeprowadzone zarówno in vitro jak i in vivo. W dużej części (50-95%) próbek ścieków pochodzących z oczyszczalni ścieków zostały wykryte związki z grupy...
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Analysis of Isocratic-Chromatographic-Retention Data using Bayesian Multilevel Modeling
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Maximum A Posteriori Bayesian Estimation of Chromatographic Parameters by Limited Number of Experiments
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Accelerated solvent extraction-gas chromatographic determination of acidic herbicides in soil
PublicationPrzyspieszona 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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Challenges in preparing honey samples for chromatographic determination of contaminants and trace residues
PublicationThe determination of contaminations and residues in honey is of growing concern over past few years, especially that these compounds can not only diminish beneficial properties of honey but more importantly, if present in significant amounts, can pose serious threat to human health. Since honey is characterized by complex composition of the matrix sample, it is often necessary to apply clean-up step, in order to eliminate interfering...
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Recent Trends in the Application of Chromatographic Techniques in the Analysis of Luteolin and Its Derivatives
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Green sample preparation techniques for chromatographic determination of small organic compounds
PublicationAccurate monitoring of the state of the environment requires the introduction of additional isolation and/or preconcentration step prior to the chromatographic determination. In this work the information about novel methodological and instrumental solutions in relation to different variants of microextraction techniques are presented. Attention is focused on analytical procedure and suitable analytical tools for extraction of the...
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Analysis of volatile fraction selected hybrid fruits using chromatographic techniques
PublicationAt present, "healthy eating" is gaining in popularity. Many people associate this term with eating plenty of vegetables and fruits. The basic elements influencing the selection of fruit are their appearance and smell. Of course, their origin and impact on human health are also very important. In recent years, exotic fruits have become increasingly accessible, making them gaining popularity, even among Poles. You can also meet plants...
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Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis
PublicationThis work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS...
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Polycyclic aromatic hydrocarbons as test probes to investigate the retention behavior of 1,3-alternate calix[4]arene silica-bonded stationary phases
PublicationA series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, fourring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated...
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Apparent molar volumes and compressibilities of selected electrolytes in dimethylsulfoxide
PublicationDensities at T = (293.15, 298.15, 303.15, 313.15, 323.15, and 333.15) K and sound velocities at T = 298.15 K of tetraphenylphosphonium bromide, sodium tetraphenylborate, sodium bromide, and sodium perchlorate in dimethylsulfoxide have been measured over the composition range from (0 to 0.3) mol kg1. From these data, apparent molar volumes and apparent molar isentropic compressibilitiesat infinite dilution as well as the expansibilities...
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Thin layer chromatography in drug discovery process
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The buckling analysis of a cold-formed steel C-sectional column resting on an elastic foundation
PublicationThe paper is focused on stability analysis of different models of steel cold-formed C-section column. The analysed element may be applied as a primary load-bearing member in steel trusses or silo columns. The column can be used as a support for a wall of roof plates made of corrugated sheets. The wall sheeting that restrains the column against buckling may be considered as an elastic foundation. Due to the design solutions the...
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Influence of a Lighting Column in the Working Width of a W-Beam Barrier on TB51 Crash Test
PublicationRoad equipment, such as, e.g., road safety barriers and lighting columns, are subject to certification according to the EN1317 standard to be allowed for use on European roads. In engineering practice, due to the terrain conditions, there are cases where other road equipment is installed within the working width of road safety barriers. Such situations are not considered during the certification process. Hence, the aim of this...
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The effect of nonlinear restraint on torsional buckling and post-buckling behaviour of a thin-walled column
PublicationW pracy rozważa się wyboczenie skrętne i zachowanie pokrytyczne osiowo ściskanego swobodnie podpartego pręta cienkosciennego o przekroju otwartym ze sprężytą nieliniową podporą w środku rozpietości. Rozwiązanie problemu wyznaczono za pomocą metody małego parametru. W przykładzie numerycznym wyznaczono siłę krytyczną i ścieżkę początkowego zachowania pokrytycznego dwuteowego pręta z podporą sprężystą o charakterystyce składającej...
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Determination of β-blockers and β-agonists using gas chromatography and gas chromatography–mass spectrometry – A comparative study of the derivatization step
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Optimal conditions of naphthoquinones separation from carnivorous plants extracts using thin-layer chromatography and high performance liquid chromatography
PublicationDroseraceae plants are owned by the family of carnivorous plants, which in an unusual way adapt to environments poor in nutrients. Droseraceae obtain essential nutrients catching insects and other small invertebrantes. Plumbagin, chloroplumbagin, ramentaceon and droseron are naphthoquinones, which could be found in leaves and shoots of plants from Droseraceae family. In the literature there are a lot of information about the pharmacological...
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Classification and fingerprinting of kiwi and pomelo fruits by multivariate analysis of chromatographic and spectroscopic data
PublicationThe fingerprinting capacity of two analytical techniques, HPLC and UV-Vis spectroscopy in the case of fruits samples (kiwi and pomelo) has been investigated. The multivariate exploratory techniques were used for sample discrimination according to the fruit species and subspecies. The combination of principal component analysis with linear discriminant analysis is opening new directions in the fingerprinting analysis. The classifications...
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New supervised alignment method as a preprocessing tool for chromatographic data in metabolomic studies
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Matrix solid-phase dispersion with sand in chromatographic analysis of essential oils in herbs
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Chromatographic behaviour of ionic liquid cations in view of quantitative structure-retention relationship
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Solid-phase microextraction and ion chromatographic analysis of anions based on polypyrrole electrode
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Optimization of liquid chromatographic separation of pharmaceuticals within green analytical chemistry framework
PublicationThe contribution is aimed at the development of methodology that allows to consider green analytical chemistry criteria during optimization of liquid chromatographic separation with design of experiment. The objectives of the optimization are maximization of peak areas of five non-steroid anti-inflammatory drugs, maximization of resolution between peaks, with simultaneous shortening of chromatographic separation time and minimization...
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Comparison of an Electronic Nose Based on Ultrafast Gas Chromatography, Comprehensive Two-Dimensional Gas Chromatography, and Sensory Evaluation for an Analysis of Type of Whisky
PublicationWhisky is one of the most popular alcoholic beverages. There are many types of whisky, for example, Scotch, Irish, and American whisky (called bourbon). The whisky market is highly diversified, and, because of this, it is important to have a method which would enable rapid quality evaluation and authentication of the type of whisky. The aim of this work was to compare 3 methods: an electronic nose based on the technology of ultrafast...
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Apparent molar volumes and compressibilities of electrolytes and ions in gamma-butyrolactone
PublicationW oparciu o zmierzone wartości gęstości roztworów i rozpuszczalnika w temperaturach od 15 do 40oC wyznaczono pozorne molowe objętości bromku litu, nadchloranu litu, nadchloranu sodu, tetrafenyloboranu sodu oraz bromku tetrafenylofosfoniowego w gamma-butyrolaktonie. Ponadto, wyznaczone prędkości rozchodzenia się dźwięku w 25oC w badanych układach pozwoliły obliczyć pozorne molowe ściśliwości wybranej grupy soli. Uzyskane (w wyniku...
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Sterowanie kolumną rektyfikacyjną z wykorzystaniem nieliniowego algorytmu predykcyjnego
PublicationPopularną metodą rozdziału ciekłych mieszanin wieloskładnikowych jest rektyfikacja, stosowana w różnych gałęziach przemysłu. W artykule rozważana jest mieszanina etanol-woda. Przedstawiono powszechnie stosowany nieliniowy model dwuskładnikowej kolumny rektyfikacyjnej, dokonano jego dyskretyzacji i zaimplementowano w środowisku MATLAB/Simulink. Następnie zaprojektowano układ sterowania wykorzystując nieliniowy algorytm predykcyjny....