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Current trends in analytical strategies for the determination of polybrominated diphenyl ethers (PBDEs) in samples with different matrix compositions – Part 2: New approaches to PBDEs determination
PublicationHerein, we review the latest technical solutions for polybrominated diphenyl ethers (PBDEs) determination in samples with different matrix compositions, largely focusing on gas chromatography but also presenting some liquid chromatography–based solutions. Moreover, we discuss the use of diverse sample injection techniques while considering the advantages and disadvantages of each injection system in the context of PBDEs analysis....
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ACTA CHROMATOGRAPHICA
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High-performance liquid chromatography thermodynamic study of new potential antiepileptic compounds on a cholesterol column using isocratic elution with methanol/water and acetonitrile/water eluent systems
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Direct design of Controlled Modulus Columns (CMC) based on in-situ testing
PublicationIn this paper, the serviceability limit state and bearing capacity of tension screw displacement piles were analyzed using the results of static pile load tests, carried out on the test plot near the Elbląg city, and field, and laboratory tests. The paper presents the methodology of determining the pile load-settlement curve using different types of t-z transfer functions. The new method of constructing the pile load-settlement...
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On some aspects of torsional buckling of thin-walled I-beam columns
PublicationW pracy podsumowano wyniki badań zjawiska wyboczenia skrętnego prętów o przekroju dwuteowym. Zbadano wpływ początkowego wygięcia giętnego na wartość siły krytycznej wyboczenia skrętnego. Z zasady stacjonarności energii potencjalnej wyprowadzono równania różniczkowe wyboczenia skrętnego. Wartość siły krytycznej wyznaczono stosując podejście perturbacyjne. Wyniki analityczne porównano z rezultatami otrzymanymi za pomocą 6-parametrowej...
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Distortional buckling of thin-walled columns of closed quadratic cross-section
PublicationThe elastic stability of axially compressed column related to the cross-section distortion is investigated. Two kinds of closed quadratic cross-sections are taken into consideration with internal walls and without it. The governing differential equation is derived with aid of the principle of stationary total potential energy. The critical loads for the simply supported columns are found in an analytical form and compared with...
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The use of GFRP tubes as load-bearing jackets in concrete-composite columns
PublicationThe paper presents the fields of applications of polymer composites in building structures. The use of composite glass fibre tubes is discussed in more detail. The laboratory methods used to test the mechanical properties of these pipes are presented. An original research program is presented, including six concrete-filled glass fibre tubes. The cylinders and columns made in this way were tested for their axial load capacity. Conclusions...
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Numerical analysis on axial capacity of steel built-up battened columns
PublicationThis paper deals with the numerical analysis aimed at study the bearing capacity of pinended steel built-up columns under axial compression. Finite element (FE) models were performed for the columns presented in the literature. The main problem discussed in the article is the shape and magnitude of geometric imperfections introduced into the numerical FE model, necessary to obtain the load capacity consistent with the experimental...
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COMPUTER-AIDED CONSTRUCTION AT DESIGNING REINFORCED CONCRETE COLUMNS AS PER EC
PublicationThe article presents the author’s computer program for designing and dimensioning columns in reinforced concrete structures taking into account phenomena affecting their behaviour and information referring to design as per EC. The computer program was developed with the use of C++ programming language. The program guides the user through particular dimensioning stages: from introducing basic data such as dimensions, concrete...
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Green chromatography
PublicationAnalysis of organic compounds in samples characterized by different composition of the matrix is very important in many areas. A vast majority of organic compound determinations are performed using gas or liquid chromatographic methods. It is thus very important that these methods have negligible environmental impact. Chromatographic techniques have the potential to be greener at all steps of the analysis, from sample collection...
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Photogrammetric and total station's measurement of compressed column's model
PublicationModelling studies continue to play an important role. One of such study is stress determination in the reinforcement bars of reinforced columns and determine column's axis deformation. The article presents measurements results of control points located on the model of reinforced concrete column. The column was compressed in few series till it's destruction. In this studies, photogrammetric method and total station measurements...
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Using different types of capillary columns as denudation traps: a comparision of sorption properties
PublicationOpisano badania odcinków kapilarnych kolumn chromatograficznych (WCOT, SCOT,PLOT) jako pułapek denudacyjnych do ilościowego zatrzymywania śladowych ilości lotnych związków organicznych ze strumienia powietrza. W trakcie badań modelowych (z wykorzystaniem gazowych mieszanin wzorcowych) określono wartości współczynników podziału benzenu, toluenu, etylobenzenu, o-ksylenu i chlorobenzenu (Kfs). Stwierdzono, że grubość filmu fazy stacjonarnej...
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Selected problems of stability of thin-walled columns with bisymmetric open cross-section
PublicationPraca dotyczy problemów stateczności osiowo ściskanych prętów o bisymetrycznym przekroju otwartym. Badano wpływ nieliniowości materiału pręta oraz wstępnego zakrzywienia osi na wyboczenie skrętne oraz początkową ścieżkę pokrytyczną. Na przykładach numerycznych wykazano, że w pewnych przypadkach stateczny, symetryczny punkt może zmienić się na symetryczny ale niestateczny, co oznacza możliwość redukcji siły krytycznej.
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Sensitivity analysis of buckling loads of bisymmetric I-section columns with bracing elements
PublicationWyznaczono pierwsza wariacje siły krytycznej wyboczenia słupa o przekroju bisymetrycznym otwartym przy wariacji sztywnosci i połozenia stezen. Przyjeto załozenia klasycznej teorii pretów cienkosciennych o nieodkształcalnym przekroju poprzecznym. Analizowano zarówno stezenia boczne jak i stezenia ograniczajacespaczenie oraz skrecenie przekroju poprzecznego. Stezenia modelowano jako podpory sprezyste. W przykładzie numerycznym zbadano...
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Simplified stability analysis of steel cylindrical silos with corrugated walls and vertical columns
PublicationIn the paper a simplified stability analysis of steel cylindrical silos composed of corru¬gated walls and vertical open-sectional columns was proposed. The whole 3D silo was modeled as a single column resting on elastic foundation provided by the silo walls. In proposed formula for the calculation of the foundation stiffness the curvature of the silo walls was taken into account. Three different analyses were carried out using...
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Experimental study on steel columns subjected to impact load under earthquake conditions
PublicationEarthquakes affecting urbanized regions cause exceptional loads to load bearing structural elements such as columns. Such a boost in the load conditions can lead to severe damages which, in a worst case scenario, can lead to a total collapse of a building. This boost is caused by the horizontal ground movement generating a rise in the internal forces due to considerable large displacement between the top and bottom support of columns....
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Investigation of buckling resistance of columns using non-linear static and dynamic analysis
PublicationThe aim of this paper is to investigate the stability process in an axially compressed column using a static and dynamic finite element analysis by taking both the geometric and material non-linearity into account. The perfect column and column with geometric imperfections were analysed. The linear buckling analyses were used to obtain the lowest buckling load and shapes of buckled forms that were taken into account as initial...
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FE-analysis of failure behaviour of reinforced concrete columns under eccentric compression
PublicationArtykuł omawia obliczanie słupów żelbetowych poddanych ściskaniu mimośrodowemu z uwzględnieniem lokalizacji odkształceń. Obliczenia wykonano przy zastosowaniu MES i sprężysto-plastycznego prawa konstytutywnego rozszerzonego o długość charakterystyczną mikrostruktury za pomocą teorii nielokalnej.
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Application of ionic liquids in chromatographic techniques
PublicationCiecze jonowe (ang. Ionic Liquids, ILs) z uwagi na swoje unikalne właściwości fizyko – chemiczne oraz możliwość prostej modyfikacji budowy, w znacznym stopniu przyczyniły się do rozwoju technik rozdzielania. W chromatografii gazowej fazy stacjonarne w postaci cieczy jonowych stanowią istotne uzupełnienie istniejących faz stacjonarnych na bazie polisiloksanów i glikolu polietylenowego. Ze względu na wysoką stabilność termiczną...
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Buckling analysis of cold formed steel column
PublicationW pracy przedstawiono analizę słupa zimnogiętego o przekroju otwartym. Przeprowadzono analizy statyczne liniowe i nieliniowe. Analizowano wpływ podłoża sprężystego oraz sztywność połączenia dwóch sąsiednich słupów.
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Buckling Analysis of Cold Formed Silo Column
PublicationThe paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....
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JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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Journal of High Resolution Chromatography
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Trends in Chromatography
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Load introduction to composite columns revisited—Significance of force allocation and shear connection stiffness
PublicationThe AISC 360-16 Specification recommends that the design shear force between parts of a composite column in the load introduction area shall be calculated based on the force allocation at ultimate limit state. Applicability of this straightforward method to the load levels that usually arise in slender composite columns is questionable, as this capacity-based force allocation is only true when the axial force is equal to the plastic...
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Experimental and numerical study on deformed steel columns subjected to impact load during earthquakes
PublicationThe soft-storey failure is one of the most typical types of damage observed in buildings during earthquakes. The failure of an upper soft storey of a structure results in large impact load acting on the lower floors and if the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of the whole building. The aim of the present paper is to investigate the dynamic behaviour...
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Behaviour of deformed steel columns exposed to impact load during earthquakes - experimental study
PublicationIt has been observed during major earthquakes that the so called soft-storey failure of an upper floor of a structure results in large impact load acting on structural members of the lower storeys. It may further lead to progressive collapse of the whole structure substantially intensifying human and material losses. The aim of this paper is to investigate experimentally the behaviour of horizontally deformed columns (deformation...
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Behaviour of deformed steel columns exposed to impact load during earthquakes: numerical analysis
PublicationIt has been observed during earthquakes that the so called soft-storey failure of an upper floor of a building leads to considerable vertical impact load acting on structural members of the lower storeys. The aim of this paper is to investigate numerically the behaviour of horizontally deformed columns (deformation as the result of earthquake loading) that are additionally subjected to vertical impact load. In the first stage of...
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Experimental study on the behaviour of steel columns under seismic-induced axial impact load
PublicationIt has been observed during major earthquakes that the so called soft-storey failure of an upper floor of a structure results in large impact load acting on structural members of the lower storeys. It may further lead to progressive collapse of the whole structure substantially intensifying human and material losses. Therefore, the aim of this paper is to investigate experimentally the behaviour of columns under bending (observed...
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Distortional buckling of composite thin-walled columns of a box-type cross section with diaphragms
PublicationDistortional buckling of axially compressed columns of box-like composite cross sections with andwithout internal diaphragms is investigated in the framework of one-dimensional theory. The channel membersare composed of unidirectional fibre-reinforced laminate. Two approaches to the member orthotropic materialare applied: homogenization based on the theory of mixture and periodicity cells, and homogenization basedon the Voigt–Reuss...
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Enhancing the Seismic Resistance of Columns by GFRP Confinement Using Flexible Adhesive-Experimental Study
PublicationIn this paper, the results of two experiments, focused on testing the effectiveness of a method of enhancing the seismic (dynamic) resistance of masonry columns with the use of flexible polymer adhesive, are shown. The first experiment was devoted to investigate the damping properties of a polymer working between two stiff layers, whereas the aim of the second one was to verify if the identified damping properties of the polymer...
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Degradation of stiffness of building columns exposed to bending and impact load during ground motions
PublicationThe safety of civil engineering structures under external loads, including ground motions, is one of the issues related to the idea of sustainable society. The earthquake-induced soft-storey failure is a typical type of damage observed in buildings due to seismic excitation. The failure of an intermediate soft storey of a structure results in large vertical impact loading acting on the lower floors due to the fall of the upper...
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The Idea of Using Adhesive Bonds in Shaping of Cold-formed Thin-walled Beam-columns
PublicationThe chapter concerns the idea of using adhesive bonds in the shaping of cold-formed thin-walled beam-columns. The idea of adhesive-bonded connections is not new but is unlikely to have been used in the design and shaping of thin-walled beam-columns in civil engineering up to date. Metal bar structures, including (due to economic reasons) thin-walled structures, are the most common and effective means to build engineering superstructures/loadbearing...
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Full-scale experiments on wheat flow in steel silo composed of corrugated walls and columns
PublicationArtykuł omawia wyniki doświadczalne w dużej skali odnośnie przepływu pszenicy w stalowym silosie wykonanym z blachy falistej i słupów. Pomierzono napory poziome i pionowe na ścianie oraz siły pionowe w słupach. Zbadano rodzaj przepływu w zależności od położenia wylotu. Wyniki naporów porównano z Eurokodem.
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Developments in Green Chromatography
PublicationGreen analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents...
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Retention modeling of some saccharides separated on an amino column.
PublicationUsing an amino column (Supelcosil LC-NH2) and different mixtures of acetonitrile-water, quantitative structure-retention relationship models are discussed. These models are based on computed molecular descriptors representing numerically structured features of some saccharides. The obtained results are underlining the lipophilicity/hydrophilicity balance, and how this is controlling the separation of the saccharides. The resulting...
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Preparation of samples of plant material for chromatographic analysis
PublicationPrzedstawiono informacje literaturowe nt. etapów przygotowania próbek materiału roślinnego do analizy chromatograficznej. Szczególną uwagę zwrócono na techniki izolacji i/lub wzbogacenie analitów przed etapem oznaczeń końcowych, walidację stosowanych procedur, sposoby pobierania próbek celem określenia emisji biogenicznej lotnych związków organicznych.
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Thermodynamic vs. extrathermodynamic modeling of chromatographic retention
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New approaches to chromatographic determination of lipophilicity of xenobiotics
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Chromatographic Examinations in the Gas Network Odourised by Tetrahydrothiophene
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Green Chromatography: State-of-the-art, Opportunities and Future Perspectives
PublicationIt is well known that chromatographic procedures could have a significant impact on the environment if laboratory practice is not in line with the principles of green analytical chemistry (GAC). However, chromatographic techniques have the potential to be greener in all steps of the analysis. The approaches used to make chromatographic separations greener differ depending on the type of chromatographic method. This chapter considers...
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Comparison of RP-HPLC columns used for determination of nucleoside metabolic patterns in urine of cancer patients
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Study on 19th-century cast iron columns from the former financial office building in Kwidzyn
PublicationThe article presents the results for cast iron columns used as floor supports in the former financial office building in Kwidzyn (Poland).The stocktaking drawings provided the general and detailed data about the 19th century designer’s decisions. During the research, architectural and structural analysis was carried out. The graphics were used as a starting material for preparing 3D calculation models. The FEM-based numerical simulations...
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Pore Water Pressure Development in Soft Soil due to Installation and Loading of Controlled Modulus Columns
PublicationExcess pore water pressure (EPWP) development and decay due to the installation and static loading tests of controlled modulus columns (CMC) in soft soil was measured with piezometers equipped with low air entry (LAE) filters and a piezocone (CPTU) equipped with a high air entry (HAE) filter. The HAE filter allows for detailed detection of EPWP in short time intervals during construction of CMC. The influence zone due to the installation...
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Comparison of buckling resistance of columns modelled by beam and shell elements using non-linear analysis
PublicationThe aim of the paper is to investigate the stability process in the axially compressed columns modelled by beam and shell elements using static and dynamic finite element analysis by taking both the geometric and material non-linearity into account. The perfect columns and columns with geometric imperfections were analysed. The differences between the results of static and dynamic analyses in shell and beam models were discussed.
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A selection of the optimal eluent components for separation of carnivorous plants metabolites by planar chromatography chromatography
PublicationAbstract: The development of the new procedures of the separation components with the complicated chemical structure from natural complex matrix by column chromatography is very difficult and in many cases expensive. Therefore to pre-select the conditions of the separation process the use of thin layer chromatography (TLC) is proffered. The possibility of proceeding the chromatographic process for several mixtures on single plate,...
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Determination of the shape of the CFGFT cylindrical column based on laboratory tests
PublicationAnalyses were carried out on glass-fibre-reinforced polymer tube columns with reference to laboratory tests. The angles of the glass fibre beams were 20◦, 55◦ and 85◦. The study employed non-classical operational calculus. Various modulated harmonic signal shapes were considered for columns and tubes at buckling. The buckling loads were assessed and compared for different models.
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Oxygen accumulation rate with and without live bacteria in column bioreactors
PublicationBadano wnikanie i akumulację tlenu w reaktorach airlift z cyrkulacją zewnetrzną. Stosowano reaktory z odwrotną warstwą fluidalną w strefie opadania, warstwą fluidalną w strefie wznoszenia oraz reaktor z cyrkulującą zawiesiną. Badano wpływ prędkości przepływu powietrza oraz stężenia cząstek stałych na szybkośc akumulacji tlenu w cieczy w reaktorach nie zawierających bakterii oraz w obecności bakterii Acinetobacter calcoaceticus...
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THE INTERACTION BETWEEN STEEL COLUMN CHORD AND CLOSELY SPACED REINFORCEMENT.
PublicationNowadays, more often than before, civil engineering designers are willing to use steel build-up members composed of single or doubled cold-formed chords interconnected using different mechanical connectors. This paper subject is an analysis of cooperation of a closely spaced built-up cold-formed chord interconnected with series of bolts that are located along the length of the member in a specific spacing. This distance along the...
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Influence of stirrups in a concrete shell on strengthening reinforced concrete column
PublicationTwelve concrete columns, with a 150x150mm square section and three columns with a circular section (d=200mm), are tested to investigate the effect of strengthening by RC jacket. Based on a confined concrete model for axial static loading, an analytical methods, reported in the literature are proposed to predict the behavior of columns with RC jacket. The results support the conception that the effect of strengthening depends...