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Search results for: TWO-PHOTON ABSORPTION
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Two-dimensional gas chromatography – principles and application in fruits analysis
PublicationTwo-dimensional gas chromatography is a rapidly developing analytical technique. One of the major uses of this technique is its use for food analysis. The paper presents the principle of operation and history of this analytical technique. The specification of the two-dimensional gas chromatography technique has been discussed. The principles of separation of ingredients and application of the method, particularly in the analysis...
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Self-compacting grout to produce two-stage concrete
PublicationTraditional concrete (TC) is primarily composed...
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Characterization of two aminotransferases from Candida albicans
PublicationAminoadipate aminotransferase (AmAA) is an enzyme of α-aminoadipate pathway (AAP) for l-lysine biosynthesis. AmAA may also participated in biosynthesis or degradation of aromatic amino acids and in d-tryptophan based pigment production. The AAP is unique for fungal microorganisms. Enzymes involved in this pathway have specific structures and properties. These features can be used as potential molecular markers. Enzymes catalyzing...
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Evaluation of mercury content in combustible tobacco products by employing cold vapor atomic absorption spectroscopy and considering the moisture content: a comprehensive study
PublicationPlants are mainly made up of water, which constitutes between 80 and 90% of their weight. Moisture factor comes across as one of the most important in tobacco products. Rapid determination of moisture content in tobacco products comes at neces- sity in any tobacco management plants (before and after production). Therefore, the concern has been raised in this study to evaluate the moisture content in four kinds of combustible tobacco...
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Two-particle entropy and structural ordering in liquid water
PublicationEntropies of simple point charge (SPC) water were calculated over the temperature range 278-363 K using the two-particle correlation function approximation. Then, the total two-particle contribution to the entropy of the system was divided into three parts, which we call translational, configurational, and orientational. The configurational term describes the contribution to entropy, which originates from spatial distribution of...
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Microwave absorption study on (Bi, Pb)-Sr-Ca-Cu-O granular superconductors
PublicationNadprzewodniki granulaste są bardzo ciekawymi materiałami dzięki temu, że zawierają dużą ilość złącz Josephsona. W pracy przedstawiono absorpcję mikrofalową w granulastych nadprzewodnikach (Bi, Pb)-Sr-Ca-Cu-O zawierających granule 2201, 2212 i 2223 umieszczone w matrycy dielektrycznej. Obserwowano dwustopniowe przejście do stanu nadprzewodzącego. Sygnał MMMA obserwowano poniżej temperatury T1.
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Enhancing Luminescence and X-ray Absorption Capacity of Eu3+:LaF3 Nanoparticles by Bi3+ Codoping
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Photoacoustic and optical absorption spectroscopy studies of luminescentCr3+andCr4+centers in yttrium aluminum garnet
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Single‐walled carbon nanotubes modified by PFO: An optical absorption and Raman spectroscopic investigation
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Different Aspects of the Elemental Analysis of Honey by Flame Atomic Absorption and Emission Spectrometry: A Review
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Determination of total mercury in fish and cormorant using cold vapour atomic absorption spectrometry
PublicationW pracy opisano technikę CV-AAS do oznaczania zawartości rtęci całkowitej w tkankach ryb i kormorana. Przedstawiono proces walidacji zastosowanej procedury analitycznej, w ramach którego wyznaczono takie parametry walidacyjne jak:- selektywność,- liniowość (r>0,993),- zakres pomiarowy (0,29-100 ng),- poprawność (odzysk 98%),- powtarzalność (CV <10%).Wartość rozszerzonej niepewności <13%.Przedstawiono wyniki pomiarów dla 8 gatunków...
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The bismuth atom neighbourhood in bismuth-silicate glasses from X-ray absorption experiment
PublicationPraca zawiera wyniki strukturalnej analizy EXAFS lokalnego otoczenia atomów bizmutu w krystalicznym tlenku bizmutu (odmiana alfa) i w szklach bizmutowo-krzemianowych o składzie xBi2O3 (1-x)SiO2,x=0.3, 0.4, 0.5, 0.6. Analizę XA- FS realizowano w oparciu o metodę GNXAS. Otrzymane wyniki porównano z danymi literaturowym.
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On the correspondence between two- and three-dimensional Eshelby tensors
PublicationWe consider both three-dimensional (3D) and two-dimensional (2D) Eshelby tensors known also as energy–momentum tensors or chemical potential tensors, which are introduced within the nonlinear elasticity and the resultant nonlinear shell theory, respectively. We demonstrate that 2D Eshelby tensor is introduced earlier directly using 2D constitutive equations of nonlinear shells and can be derived also using the throughthe-thickness...
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Mechanical properties of two-stage concrete modified by silica fume
PublicationAbstract. Two-stage concretes, despite the fact that they have proven themselves in various types of construction, have not been studied to the same extent as traditional heavy concretes. Therefore, the article developed the composition of frame concrete with various additives in the composition of the cement-sand mortar. A comparison of the mechanical characteristics of the developed compositions with the addition of silica fume...
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Two complementary approaches for the synthesis and isolation of stable phosphanylphosphaalkenes
PublicationPhospha-Wittig (phosphanylphosphinidene titanium(IV) complex) and phospha-Peterson (lithiated diphosphane) reactions were used to obtain phosphanylphosphaalkenes with the general formula XYC=P-PtBu2 (X = alkyl, aryl group or H; Y = alkyl or aryl group). Therefore, two series of reactions with different ketones and aldehydes were performed. An examination revealed that the two methods are complementary. For smaller carbonyl compounds,...
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A two dimensional approach for modelling of pennate muscle behaviour
PublicationThe purpose of this study was to elaborate a two-dimensional approach for unipennate and bipennate striated skeletal muscle modelling. Behavior of chosen flat pennate muscle is modelled as a rheological system composed of serially linked passive and active fragments having different mechanical properties. Each fragment is composed of three elements: mass element, elastic element and viscous element. Each active fragment furthermore...
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Flow Boiling in Minigap in the Reversed Two-Phase Thermosiphon Loop
PublicationThe paper presents the results of experimental investigations of a model of a heat exchanger featuring a minigap, which is perceived as an evaporator for an inverted thermosiphon. The system works with a single component test fluid. The tested evaporator generates pumping power in the test loop in a way similar to the mammoth pump. The tests regarded a module of the heat exchanger, consisting of a hot leg and a cold leg with the...
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Abundance and biomass of bacteria in two Arctic glacial fjords
PublicationTotal numbers and biomass of bacterioplankton in water in two glacial fjords off west Spitsbergen have been studied. Samples were collected from different water depth layers - from the surface to 80-90 m. Total bacterial number (TBN), biomass and morphological structure were determined by the acridine orange direct count method. The highest values of TBN and biomass in the water column were found on stations situated adjacent...
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Two Stage SVM and kNN Text Documents Classifier
PublicationThe paper presents an approach to the large scale text documents classification problem in parallel environments. A two stage classifier is proposed, based on a combination of k-nearest neighbors and support vector machines classification methods. The details of the classifier and the parallelisation of classification, learning and prediction phases are described. The classifier makes use of our method named one-vs-near. It is...
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Study on applicability of two modal identification techniques in irrelevant cases
PublicationStudy on applicability of two modal identification techniques in irrelevant cases is made in this paper. The following techniques are considered: Peak Picking based on correlation analysis (PP-CA), dedicated for ambient vibrations and Eigensystem Realization Algorithm (ERA), formulated for free decay vibrations investigation. Irrelevant cases are found when analyzed signals are different than recommended to a given technique. The...
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Relativistic two-dimensional hydrogen-like atom in a weak magnetic field
PublicationA two-dimensional (2D) hydrogen-like atom with a relativistic Dirac electron, placed in a weak, static, uniform magnetic field perpendicular to the atomic plane, is considered. Closed forms of the first- and second-order Zeeman corrections to energy levels are calculated analytically, within the framework of the Rayleigh–Schrödinger perturbation theory, for an arbitrary electronic bound state. The second-order calculations are...
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Experimental investigation of two-phase thermosyphon heat exchanger charged with acetone
PublicationThis paper presents thermal characteristics of prototype of a two-phase thermosyphon heat exchanger (TPTHEx) charged with acetone as a working fluid. The TPTHEx consists of two horizontal cylindrical vessels connected by two risers and a downcomer. Tube bundles placed in the lower and upper cylinders work as an evaporator and a condenser, respectively. The tested TPTHEx operates in a vacuum. Therefore, the working liquid is boiled...
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Periodicity-induced effects in the scattering and absorption of light by infinite and finite gratings of circular silver nanowires
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Anomalous diffraction approach to the visible spectra of absorption by marine particles with power-law size distributions
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Determination of butyltin stabilizers in PVC using Liquid-Phase microextraction with electrothermal atomic absorption spectrometry
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Path components of the space of gradient vector fields on the two dimensional disc
PublicationWe present a short proof that if two gradient maps on the twodimensional disc have the same degree, then they are gradient homotopic.
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EFFECT OF NANOFLUID CONCENTRATION ON TWO-PHASE THERMOSYPHON HEAT EXCHANGER PERFORMANCE
PublicationAn approach – relaying on application of nanofluid as a working fluid, to improve performance of the two-phase thermosyphon heat exchanger (TPTHEx) has been proposed. The prototype heat exchanger consists of two horizontal cylindrical vessels connected by two risers and a downcomer. Tube bundles placed in the lower and upper cylinders work as an evaporator and a condenser, respectively. Distilled water and nanofluid water-Al2O3...
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Investigation of Thermoplastic Polyurethanes Synthesized via Two Different Prepolymers
PublicationThe man aim of this work was to investigate the effect of the molecular weight of polyols, mixture of prepolymers, and [NCO]/[OH] molar ratio used during the prepolymer chain extending step on the chemical structure, thermomechanical and mechanical properties, and thermal stability of thermoplastic poly(ether-urethane)s In this work thermoplastic poly(ether-urethane)s were synthesized by using polyols with a various molecular weight,...
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Numerical Simulations of Seepage in Dikes Using unsaturated and Two-Phase Flow Models
PublicationModeling of water flow in variably saturated porous media, including flood dikes, is often based on the Richards equation, which neglects the flow of pore air, assuming that it remains at constant atmospheric pressure. However, there is also evidence that the air flow can be important, especially when the connectivity between the pore air and atmospheric air is lost. In such cases a full two-phase air-water flow model should be...
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Two-dimensional hydrogen-like atom in a weak magnetic field
PublicationWe consider a non-relativistic two-dimensional (2D) hydrogen-like atom in a weak, static, uniform magnetic field perpendicular to the atomic plane. Within the framework of the Rayleigh-Schr¨odinger perturbation theory, using the Sturmian expansion of the generalized radial Coulomb Green function, we derive explicit analytical expressions for corrections to an arbitrary planar hydrogenic bound-state energy level, up to the fourth...
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Ionization and fragmentation of the six-membered heterocycles containing oxygen – Comparative studies of electron and photon impact on the 3,4-dihydro-2H-pyran molecules
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Exactly solvable model of two interacting Rydberg-dressed atoms confined in a two-dimensional harmonic trap
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Conformational Studies of Two Bradykinin Antagonists by Using Two-dimensional NMR Techniques and Molecular Dynamics Simulations
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Existence of Two Periodic Solutions to General Anisotropic Euler-Lagrange Equations
PublicationAbstract. This paper is concerned with the following Euler-Lagrange system d/dtLv(t,u(t), ̇u(t)) =Lx(t,u(t), ̇u(t)) for a.e.t∈[−T,T], u(−T) =u(T), Lv(−T,u(−T), ̇u(−T)) =Lv(T,u(T), ̇u(T)), where Lagrangian is given by L=F(t,x,v) +V(t,x) +〈f(t),x〉, growth conditions aredetermined by an anisotropic G-function and some geometric conditions at infinity.We consider two cases: with and without forcing termf. Using a general version...
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A Comparison of Simplified Two-dimensional Flow Models Exemplified by Water Flow in a Cavern
PublicationThe paper shows the results of a comparison of simplified models describing a two-dimensional water flow in the example of a water flow through a straight channel sector with a cavern. The following models were tested: the two-dimensional potential flow model, the Stokes model and the Navier-Stokes model. In order to solve the first two, the boundary element method was employed, whereas to solve the Navier-Stokes equations, the...
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Two technologies selected for metropolitan area
PublicationZastosowanie dwóch efektywnych technologii budowlanych, tj. jet grouting i pipe roofing, przedstawiono na przykładzie realizacji budowlanych w obszarze aglomeracji miejskiej. Technika jet grouting znalazła bardzo interesujące zastosowanie przy wykonywaniu szczelnych przesłon przeciwfiltracyjnych, które znacząco ograniczają napływ wody gruntowej do wykopu i umożliwiają przez to swobodne prowadzenie prac fundamentowych. Przedstawiona...
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Experimental investigation of a two-phase thermosiphon.
PublicationPrzedstawiono wyniki badań dwufazowego, termosyfonowego wymiennika ciepła. W szczególności uwzględniono wpływ podziałki rur oraz wartość ciśnienia w płaszczu na gęstość przenoszonego strumienia ciepła.
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Signal Propagation in Electromagnetic Media Modelled by the Two-Sided Fractional Derivative
PublicationIn this paper, wave propagation is considered in a medium described by a fractional-order model, which is formulated with the use of the two-sided fractional derivative of Ortigueira and Machado. Although the relation of the derivative to causality is clearly specified in its definition, there is no obvious relation between causality of the derivative and causality of the transfer function induced by this derivative. Hence, causality...
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Application of two-dimensional intensity maps in high-accuracy polarimetry
PublicationWe propose the analysis of 2D intensity contour maps which is based on the optical transmission function for the polarizer-specimen-analyzer system. A small modification of the high-accuracy universal polarimeter (HAUP) technique was used to measure the intensity maps (HAUP maps) and determine the phase retardation, linear dichroism (LD) parameters, and multiple light reflection contribution in uniaxial crystals. We have performed...
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Bifurcation of equilibrium forms of an elastic rod on a two-parameter Winkler foundation
PublicationWe consider two-parameter bifurcation of equilibrium states of an elastic rod on a deformable foundation. Our main theorem shows that bifurcation occurs if and only if the linearization of our problem has nontrivial solutions. In fact our proof, based on the concept of the Brouwer degree, gives more, namely that from each bifurcation point there branches off a continuum of solutions.
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Oral antibiotic therapy improves fat absorption in cystic fibrosis patients with small intestine bacterial overgrowth
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A study of optical properties and annealing effect on the absorption edge of pristine- and iodine-doped polyazomethine thin films
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Improvement of CO2 absorption and inhibition of NH3 escape during CaCO3 precipitation in the presence of selected alcohols and polyols
PublicationThis research aims to investigate the effect of selected organic substances containing hydroxyl groups on the reduction of NH3 escape and the improvement of CO2 capture during the precipitation of calcium carbonate by carbonation method using post-distillation liquid from the Solvay process and gas stream containing CO2 in the amount corresponding to the exhausted gases produced by the combustion of fossil fuels. Glycerol, ethylene...
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Selfish Attacks in Two-Hop IEEE 802.11 Relay Networks: Impact and Countermeasures
PublicationIn IEEE 802.11 networks, selfish stations can pursue a better quality of service through selfish MAC-layer attacks. Such attacks are easy to perform, secure routing protocols do not prevent them, and their detection may be complex. Two-hop relay topologies allow a new angle of attack: a selfish relay can tamper with either source traffic, transit traffic, or both. We consider the applicability of selfish attacks and their variants...
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Comparative Analysis of Two Polish Hyperbolic Systems AEGIR and JEMIOLUSZKA
PublicationGlobal Navigation Satellite System (GNSS) is seen by terrorists or hostile countries as a high value target. Volpe Center report contains the following statement: “During the course of its development for military use and more recent extension to many civilian uses, vulnerabilities of Global Navigation Satellite Systems (GNSS) – in the United States the Global Positioning System (GPS) – have become apparent. The vulnerabilities...
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Two-electron entanglement in a two-dimensional isotropic harmonic trap: Radial correlation effects in the low density limit
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Attraction of Moths of Two Noctuidae Species to Field Traps Baited With a Mixture of two to three Homologous Acetates in Poland
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Comparison of two methods of sound extraction from guitar string video recordings
PublicationA comparison of two sound extraction methods from guitar string video recordings is presented in the paper. A brief overview of highframe rate camera technology and possible applications are included. The method using the image analysis from two such cameras is presented. The cameras are placed at the angle of 90 degrees for recording the image in three planes. The results achieved...
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Sustainability reporting in justice systems: a comparative research in two European countries
PublicationPurpose – That on accountability in public organizations is quite an old debate. Its introduction in judicial systems is, however, still viewed with some suspicion, due to its potential trade-off with independence and impartiality. Nevertheless, the need to respond to the demands for greater transparency and accountability has also pushed judicial organizations to establish a dialogue with a wide range of subjects. This study aims...
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Asynchronous Method of Simultaneous Object Position and Orientation Estimation with Two Transmitters
PublicationThis paper proposes an object location method for all types of applications, including the Internet of Things. The proposed method enables estimations of the position and orientation of an object on a plane or in space, especially during motion, by means of location signals transmitted simultaneously from two transmitters placed on the object at a known distance from each other. A mathematical analysis of the proposed method and...