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Migration of container terminals as their natural process of evolution: Case study of Gdańsk and Gdynia ports
PublikacjaThe paper proposes a theoretical model of container terminals and container port development, based on the life cycle theory, threshold theory and catastrophe theory, and in references to Kuznets' swings (interpreted as waves of infrastructural investments), and Kondratiev long economic waves. The aim of this model is to explain the development process of a container terminal and a port within one technological generation, as...
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Computed vibrational excitation ofCF4by low-energy electrons and positrons: Comparing calculations and experiments
PublikacjaQuantum calculations for the excitation of the asymmetric modes of the CF4 target gas, ν3 and ν4, by impact of low-energy electrons and positrons are carried out in the energy range around 1 eV and are compared with recent experimental findings. The similarities and differences between the two types of projectiles, and the two different modes, are analyzed and discussed vis à vis the present accord with the experimental results.
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International Journal of Migration Health and Social Care
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Medical Journal of Chinese People's Liberation Army
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Bożena Kostek prof. dr hab. inż.
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Application of signal to noise ratio and grey relational analysis to minimize forces and vibrations during precise ball end milling
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3D calculations of aerodynamic forces causing self-excited vibrations of turbine rotor systems. Part II: Pressure forces
PublikacjaPrzedstawiono wyniki badań numerycznych sił generowanych w uszczelnieniu nadbandażowym stopnia turbinowego przeprowadzone metodą Fluent. Uwzględniono niecentryczne położenie osi wirnika względem osi korpusu. Rozpatrzono bandaże o różnej geometrii. Niektóre wyniki zweryfikowano doświadczalnie.
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Multicopy Suppressor Analysis of Strains Lacking Cytoplasmic Peptidyl-Prolyl cis/trans Isomerases Identifies Three New PPIase Activities in Escherichia coli That Includes the DksA Transcription Factor
PublikacjaConsistent with a role in catalyzing rate-limiting step of protein folding, removal of genes encoding cytoplasmic protein folding catalysts belonging to the family of peptidyl-prolyl cis/trans isomerases (PPIs) in Escherichia coli confers conditional lethality. To address the molecular basis of the essentiality of PPIs, a multicopy suppressor approach revealed that overexpression of genes encoding chaperones (DnaK/J and GroL/S),...
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Polymeric Bearings – A New Base Isolation System to Reduce Structural Damage during Earthquakes
PublikacjaBase isolators, like lead rubber bearings, high damping rubber bearings or friction pendulum systems are extensively used in practice in many seismically active regions to protect structures against earthquake forces. The present paper reports the results obtained from the experimental study aimed to determine the effectiveness of the Polymeric Bearings in suppressing structural vibrations during dynamic excitations and therefore...
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Vibration signals collected for concrete beams with GFRP reinforcement subjected to elevated temperatures (120C-240C)
Dane BadawczeThe dataset contains the time domain signals obtained during dynamic tests of concrete beams reinforced with GFRP bars. The vibration were induced with the use of modal hammer, while the signals were collected by the accelerometers attached at the beam surface. The signals were captured before and after subjecting the concrete beams to elevated temperatures.
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Application of shifted Chebyshev polynomial-based Rayleigh–Ritz method and Navier’s technique for vibration analysis of a functionally graded porous beam embedded in Kerr foundation
PublikacjaPresent study is dealt with the applicability of shifted Chebyshev polynomial based Rayleigh-Ritz method and Navier’s technique on free vibration of Functionally Graded (FG) beam with uniformly distributed porosity along the thickness of the beam. The material properties such as Young’s modulus, mass density, and Poisson’s ratio are also considered to vary along the thickness of the FG beam as per the power-law exponent model....
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Computer simulation of vibration surveillance of discretely idealised mechanical systems. Part I: Optimal control at the energy performance index for open non-stationary systems
PublikacjaPraca dotyczy sposobów nadzorowania drgań mechanicznych z wykorzystanie elementów teorii sterowania, optymalizacji dynamicznej, nowoczesnych metod symulacji komputerowej oraz technik pomiarowych. Do modelowania niestacjonarnego układu sterowanego zastosowano mieszaną metodą sztywnych i odkształcalnych elementów skończonych. Opracowano metodę nadzorowania drgań w dziedzinie czasu, z wykorzystaniem sterowania optymalnego przy energetycznym...
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A SEARCH OF AN INDUCER GEOMETRY THAT IS BENEFICIAL FOR LIFTING PARAMETERS OF A LIFTED OBJECT OF A SELECTED SHAPE
PublikacjaThe literature describes acoustic levitation phenomena with the utilization of air squeeze film between the vibrating inducer and the lifted object. The objective of the study is to determine the shape of the inducer with vibration characteristics that would allow the levitation of an object of the assumed geometry. In this paper, the influence of the dimension ratio of the inducer on the frequency of the first mode of vibration...
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A LUMPED-CIRCUIT MODEL OF CIRCULAR PISTON TRANSDUCER FOR MODELING ITS PERFORMANCE IN DUAL FREQUENCY OPERATING MODES
PublikacjaThe paper presents novel network equivalent circuit of piezoceramic circular disc transducer that takes into account thickness and ra dial mode of vibrations. The starting point of the analysis is 4-port description of circular disc element representing the solution of wave equation set in radial and thickness directions. Th e approximate solution for harmonic case is represented in the form of 4x4 matrix, which is syn thesized...
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A technique of experiment aided virtual prototyping to obtain the best spindle speed during face milling of large-size structures
PublikacjaThe paper presents an original method concerning vibration suppression problem during milling of large-size and geometrically complicated workpieces with the use of novel way of selecting the spindle speed. This consists in repetitive simulations of the cutting process for subsequent values of the spindle speed, until the best vibration state of the workpiece is reached. An appropriate method of obtaining a computational model,...
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Theoretical study of the structure, energetics and vibrational frequencies of water-acetone and water-2-butanone complexes
PublikacjaKompleksy acetonu i 2-butanonu z 0-2 cząsteczkami wody połączonymi wiązaniem wodorowym z tlenem karbonylowym zbadano z wykorzystaniem teorii funkcjonału gęstości (DFT) na poziomie B3LYP/6-311++G(d,p). Obliczenia w fazie gazowej uzupełniono o optymalizacje w otoczeniu rozpuszczalnika, symulowanego za pomocą modelu polaryzowalnego kontinuum (PCM). Częstości drgań oscylacyjnych otrzymane na podstawie zależności empirycznej sa zgodne...
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Application of sublation and two phase titration methods for analytical of surfactants in AFFF fire-fighting foams
PublikacjaCelem badań była próba opracowania odpowiedniej metody izolacji ze ścieków fluorowanych związków powierzchniowo czynnych FZPC do celów analitycznych, a także metody ich ilościowego oznaczania. W badaniach polegających na oznaczaniu stężenia FZPC w oparciu o miareczkowanie w układzie dwufazowym: woda/chloroform użyto Hyaminy 1622, jako titranta oraz błękitu metylenowego, jako wskaźnika. Kolejnym etapem badań była izolacja ZPC z...
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Formation of OH Radicals as Evidence of Intramolecular Hydrogen Migration in Cation-Induced Dissociation of Furan Molecules
PublikacjaWe present the experimental results on a hydrogen atom migration preceding fragmentation of the furan molecules induced by the H3+ and C+ impact. The excited OH(A2Σ+) radical has been detected among the furan decomposition products using collision-induced emission spectroscopy. However, the OH moiety is absent in the furan ring skeleton, so detecting the OH(A2Σ+→X2Π) luminescence indicates the intramolecular H atom relocation prior...
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Hydrogen migration in formation of NH(A3Π) radicals via superexcited states in photodissociation of isoxazole molecules
PublikacjaFormation of the excited NH(A 3Π) free radicals in the photodissociation of isoxazole (C3H3NO) molecules has been studied over the 14-22 eV energy range using photon-induced fluorescence spectroscopy. The NH(A 3Π) is produced through excitation of the isoxazole molecules into higher-lying superexcited states. Observation of the NH radical, which is not a structural unit of the isoxazole molecule, corroborates the hydrogen atom...
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Quantum Steering Inequality with Tolerance for Measurement-Setting Errors: Experimentally Feasible Signature of Unbounded Violation
Publikacjauantum steering is a relatively simple test for proving that the values of quantum-mechanical measurement outcomes come into being only in the act of measurement. By exploiting quantum correlations, Alice can influence — steer — Bob ’ s physical system in a way that is impossible in classical mechanics, as shown by the violation of steering inequalities. Demonstrating this and similar quantum effects for systems of increasing size,...
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Hydrogen migration observed in fragmentation of the pyridine molecules in collisions with the H+, H2+, He+and He++cations
PublikacjaThe hydrogen atom migration preceding fragmentation of the pyridine molecules by the H+, H2+, He+ and He++ collisions has been investigated in the 5-2000 eV energy range. The pyridine molecule structure is lacking of the NH group, thus formation of the NH radicals is an evidence of the H atom relocation prior to the cation-induced fragmentation. The NH(A3Π) fragmentation yields measured by detecting its A3Π→X3Σ− fluorescence show...
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Rigid Finite Element Modeling for Identification of Vibrations in Elastic in Elastic Rod Driven by a DC-motor Suplied from a Thyristor Rectifier
PublikacjaRozdział dotyczy analizy numerycznej układu elektromechanicznego. Układ składa się z silnika zasilanego z jednopołówkowego prostownika tysystorowego i napędzanego tym silnikiem wirującego pręta. Celem obliczeń jest określenie postaci i wielkości drgań pręta, jeśli uwzględniamy jego elastyczność. Dyskretna struktura modelu to łańcuch wielomasowy ciał - sztywnych ciał połączonych bezmasowymi węzłami. Autorzy obliczyli zachowanie...
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An Experimentally Aided Operational Virtual Prototyping to Obtain the Best Spindle Speed during Face Milling of Large-Size Structures
PublikacjaAbstract: The paper presents an original method concerning the problem of vibration reduction in the general case while milling large-size and geometrically complex details with the use of an innovative approach to the selection of spindle speed. A computational model is obtained by applying the so-called operational approach to identify the parameters of the workpiece modal model. Thanks to the experimental modal analysis results,...
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Vibration and buckling characteristics of nonlocal beam placed in a magnetic field embedded in Winkler–Pasternak elastic foundation using a new refined beam theory: an analytical approach
PublikacjaIn this article, a new refined beam theory, namely one variable first-order shear deformation theory, has been employed to study the vibration and buckling characteristics of nonlocal beam. The beam is exposed to an axial magnetic field and embedded in Winkler–Pasternak foundation. The von Kármán hypothesis along with Hamilton’s principle has been implemented to derive the governing equations for both the vibration and buckling...
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Earthquake Engineering and Engineering Vibration
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Vibrational Sum-Frequency Generation Activity of a 2,4-Dinitrophenyl Phospholipid Hybrid Bilayer: Retrieving Orientational Parameters from a DFT Analysis of Experimental Data
PublikacjaThe vibrational nonlinear activity of films of 2,4-dinitrophenyl phospholipid (DNP) at the solid interface is measured by sum-frequency generation spectroscopy (SFG). Hybrid bilayers are formed by a LangmuirSchaefer approach in which the lipid layer is physisorbed on top of a self-assembled monolayer of dodecanethiol on Pt with the polar heads pointing out from the surface. The SFG response is investigated in two vibrational frequency...
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Experimental and Numerical Study on Dynamics of Two Footbridges with Different Shapes of Girders
PublikacjaThe paper presents the experimental and numerical results of the dynamic system identification and verification of the behavior of two footbridges in Poland. The experimental part of the study involved vibration testing under different scenarios of human-induced load, impulse load, and excitations induced by vibration exciter. Based on the results obtained, the identification of dynamic parameters of the footbridges was performed...
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Fluorescence anisotropy decay in the presence of multistep energy migration and back transfer in disordered two-component systems
PublikacjaPrzeprowadzono analizę zaniku anizotropii fluorescencji w sztywnym (lepkim) układzie dwuskładnikowym donor (Rodamina 6G)- akceptor (Rodamina B) z uwzględnieniem prostego i powrotnego transferu energii. Stwierdzono bardzo dobrą zgodność danych doświadczalnych z wynikami symulacji Monte Carlo. W pracy zaprezentowano specjalnie opracowany hybrydowy algorytm symulacji Monte Carlo anizotropii emisji, który jest bardzo wydajny w porównaniu...
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Differential cross sections for electron impact vibrational excitation of molecular oxygen in the angular range 15° - 180°.
PublikacjaZmierzono absolutne różniczkowe przekroje czynne na wzbudzenie drobin tlenu do poziomów oscylacyjnych v=1-4 stanu podstawowego X3 suma g. Pomiary wykonano dla energii elektronów równej 10eV w zakresie kątów rozproszenia od 15° do 180°.
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Excitation energy migration in uniaxially oriented polymer films: a comparison between strongly and weakly organized systems
PublikacjaMechanizm wieloetapowej migracji energii w osiowo rozciąganych foliach polimerowych jest analizowany w układach o silnej i słabej orientacji molekuł barwników umieszczonych w matrycach poliwinylowych. Porównanie tych różnie orientujących się układów bazuje na zjawisku depolaryzacji stężeniowej anizotropii emisji, symulacjach Monte Carlo i wartościach liniowego dichroizmu. Pokazano, że uporządkowanie momentów przejścia fluoroforów...
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Buffer contribution to formation enthalpy of copper(II)–bicine complex determined by isothermal titration calorimetry method
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Crystal structure and isothermal titration calorimetry studies of new cobalt(II) complex with 2-methylnitrilotriacetate ion
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Possibility of New Active Substrates (ASs) to Be Used to Prevent the Migration of Heavy Metals to the Soil and Water Environments
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Vibrational spectroscopic studies of N,N'-dimethylpropyleneurea-water system: Affected solvent spectra and factor analysis
PublikacjaZmierzono widma FT-IR układu N,N'-dimetylopropylenomocznik (DMPU) - woda w całym zakresie składów w zakresie 4000-500 cm-1 przy użyciu techniki całkowitego wewnętrznego odbicia (ATR). Hydratacja DMPU została dodatkowo zbadana przy pomocy transmisyjnej spektroskopii FT-IR izotopowo rozcieńczonej HDO w H2O. Widma zanalizowano przy użyciu ilościowej wersji metody widm różnicowych, prowadzącej do wyizolowania widma rozpuszczalnika...
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Instantaneous Heating and Cooling Caused by Periodic or Aperiodic Sound of Any Characteristic Duration in a Gas with Vibrational Relaxation
PublikacjaThermodynamic relaxation of internal degrees of a molecule's freedom in a gas occurs with some characteristic time. This makes wave processes in a gas behave differently depending on the ratio of characteristic duration of perturbations and the relaxation time. In particular, generation of the secondary non-wave modes by intense sound in a nonlinear flow dependens on frequency. These kinds of interaction are considered in this...
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The effect of shear deformations' rotary inertia on the vibrating response of multi-physic composite beam-like actuators
PublikacjaIn consecutive studies on flexomagneticity (FM), this work investigates the flexomagnetic reaction of a vibrating squared multi-physic beam in finite dimensions. It is assumed that the bending and shear deformations cause rotary inertia. In the standard type of the Timoshenko beam the rotary inertia originated from shear deformations has been typically omitted. It means the rotary inertia resulting from shear deformation is a new...
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Density functional LCAO calculations of vibrational modes and phonon density of states in the strained single-layer phosphorene
PublikacjaThe paper presents an investigation of phosphorene under axial strain on the phonon density of states and vibrational modes. The studies were performed by means of density functional theory (DFT) within the linear combination of atomic orbitals (LCAO). The strained models were constructed using optimised supercell techniques. The vibrational mode spectra were estimated for strains applied for both the zigzag and armchair directions...
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Towards a multi-basin SWAT model for the migration of nutrients and pesticides to Puck Bay (Southern Baltic Sea)
PublikacjaBackground This paper analyzes the impact of changes in fertilization on crop yields and the runoff of nutrients from a small agricultural catchment (176 km2) to a shallow bay, using the SWAT model. Puck Bay is part of the Gulf of Gdansk and belongs to the Baltic Sea. The whole area of Puck Bay (364 km2) is protected (Natura 2000) yet despite this it suffers from eutrophication problems due to the relatively minimal depth and...
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Elastic electron scattering and vibrational excitation of isoxazole molecules in the energy range from 2 to 20 eV
PublikacjaDifferential cross sections for elastic electron scattering and the excitation of the C-H vibrational modes of isoxazole molecules were measured in the energy range from 2 to 20 eV and over the scattering angle range from 10◦ to 180◦. The cross sections at the scattering angles of and above 90◦ were accessible with the use of a magnetic angle changer. The differential cross sections were integrated to yield integral and momentum...
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3D calculations of aerodynamic forces causing self-excited vibrations of turbine rotor systems. Part I: Shroud seal flow inwestigations
PublikacjaOpisano numeryczną i doświadczalną metodę badania przepływu w uszczelnieniu nadbandażowym stopnia turbinowego. Badania numeryczne przeprowadzono programem Fluent, a badania doświadczalne wykonano na powietrznej turbinie modelowej. Uwzględniono niesymetryczny rozkład szczeliny nadbandażowej na skuteknie centrycznego położenia osi wirnika względem osi cylindra. Zamieszczono przykładowe wyniki.
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Adjusting the Stiffness of Supports during Milling of a Large-Size Workpiece Using the Salp Swarm Algorithm
PublikacjaThis paper concerns the problem of vibration reduction during milling. For this purpose, it is proposed that the standard supports of the workpiece be replaced with adjustable stiffness supports. This affects the modal parameters of the whole system, i.e., object and its supports, which is essential from the point of view of the relative tool–workpiece vibrations. To reduce the vibration level during milling, it is necessary to...
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The Effect of Circular Saw Blade Clamping Diameter on its Resonant Frequencies
PublikacjaIn this paper results of comparison of characteristic resonant frequencies of circular saw blades as a function of the saw clamping diameter from the impact test are presented. Obtained results revealed that proportionally with the increase of the saw clamping diameter also the dynamical stiffness of the saw blade increased. As a consequence of that the resonant frequencies of the saw blade move to higher values. Moreover, with...
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Guitar String Sound Retrieved from Moving Pixels
PublikacjaThe aim of this study was to develop a method of visual recording and analyzing the vibrations of guitar strings using high-speed cameras and dedicated video processing algorithms. The recording of a plucked string reveals the way in which the deformations propagate, composing the standing and travelling wave. The paper compares the results for a few selected models of classical and acoustic guitars, and it involves processing...
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Scheduling jobs to contain a natural disaster: a model and complexity
Publikacjathis paper is devoted to the problem of scheduling suppression units so that a natural disaster is dealt with as efficient as possible. the concept of deteriorating jobs is adopted, that is, the formal model of scheduling represents linearly increasing value loss as the disaster remains unsuppressed and increasing time for its suppression. more precisely, two different goals are considered: finding a suppression schedule of minimal...
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Data on hydrogen migration in cation-induced dissociation of furan molecules
Dane BadawczeThe data include furan luminescence spectra obtained in collisions with H3+ and C+ cations and theoretical spectra of OH and CH radicals published in [1].
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AC Motor Voltage and Audible Noise Dataset
PublikacjaThe dataset titled AC motor voltage and audible noise waveforms in ship’s electrical drive systems with frequency converters contains the voltage and sound measurement results recorded in a marine frequency controlled AC drive system. The dataset is part of research focussing on the impact of the ship’s electrical drive systems with frequency converters on vibrations and the level of audible noise on ships. The dataset allows the...
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Implementation of Hermite-Ritz method and Navier’s Technique for Vibration of Functionally Graded Porous Nanobeam Embedded in Winkler-Pasternak Elastic Foundation Using bi-Helmholtz type of nonlocal elasticity
PublikacjaPresent study is devoted to investigating the vibration characteristics of Functionally Graded (FG) porous nanobeam embedded in an elastic substrate of Winkler-Pasternak type. Classical beam theory (CBT) or Euler-Bernoulli beam theory (EBT) has been incorporated to address the displacement of the FG nanobeam. Bi-Helmholtz type of nonlocal elasticity is being used to capture the small scale effect of the FG nanobeam. Further, the...
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Study of the Experimental and Simulated Vibrational Spectra Together with Conformational Analysis of Thioether Cyanobiphenyl-Based Liquid Crystal Dimers
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Ab initio study of phenyl benzoate: structure, conformational analysis, dipole moment, IR and Raman vibrational spectra
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Modelowanie procesów migracji zanieczyszczeń organicznych w środowisku wodnym = Modelling of migration of organic xenobiotics in aquatic environment
PublikacjaPrzedstawiono zagadnienia związane z modelowaniem migracji związków chemicznych w środowisku. Zamieszczono także sposób konstruowania modeli i przegląd najważniejszych typów modeli migracji wraz z przykładami oraz wyniki, jakie można uzyskać za pomocą poszczególnych grup modeli. W pracy zawarto również podział modeli migracji ze względu na sposób przedstawienia transportu zanieczyszczeń, poziom kompilacji i zakres obszaru modelowania....