Wyszukiwarka
Filtry
wszystkich: 1480
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: Proton transfer mechanisams
-
Minichannel and minigap classification criteria based on the aspect ratio of the minigeometry: A numerical study
PublikacjaA detailed numerical investigation has been carried out to analyze the diabatic flow distribution and velocity profile in 18 minigeometries with various aspect ratios for V-type and I-type flow configurations (for 36 cases) assuming ethanol as a working fluid. The aim of the study is to distinguish the value of the aspect ratio for which the flow in minigeometry starts to be two-dimensional (minigap). Cases with a constant Reynolds...
-
A finite element analysis of thermal energy inclination based on ternary hybrid nanoparticles influenced by induced magnetic field
PublikacjaThe use of hybrid nanoparticles to improve thermal processes is a key method that has implications for a variety of interventions utilized in many sectors. This paper aimed to look into the impacts of ternary nanoparticles on hyperbolic tangent materials to establish their thermal characteristics. Flow describing equations have been explored in the presence of heat production, non-Fourier heat flux, and an induced magnetic field....
-
Thermal boundary conditions to simulate friction layers and coatings at sliding contacts
PublikacjaA brief review of the thermal boundary conditions specified at sliding interfaces was performed. New thermal boundary conditions were derived aimed at solving problems of sliding with account of surface layers representing friction layers and tribological coatings. Based on the assumption of linear temperature distributions in the surface layers, the proposed conditions enable one to simplify simulations by eliminating the surface...
-
Partition of friction heat between sliding semispaces due to adhesion-deformational heat generation
PublikacjaAnalytical expressions of heat-partition coefficient and contact temperatures for two sliding semispaces with account for adhesion-deformational heat generation and contact heat exchange have been obtained. The rate of deformational heat generation is assumed to decay exponentially with increase of distance from the interface. It has been shown that heat-generation configuration and the intensity of contact heat exchange have impact...
-
A New Approach for the Mitigating of Flow Maldistribution in Parallel Microchannel Heat Sink
PublikacjaThe problem of flow maldistribution is very critical in microchannel heat sinks (MCHS). It induces temperature nonuniformity, which may ultimately lead to the breakdown of associated system. In the present communication, a novel approach for the mitigation of flow maldistribution problem in parallel MCHS has been proposed using variable width microchannels. Numerical simulation of copper made parallel MCHS consisting of 25 channels...
-
Photoelectron spectroscopy of a series of acetate and propionate esters
PublikacjaThe electronic state and photoionization spectroscopy of a series of acetate esters: methyl acetate, isopropyl acetate, butyl acetate and pentyl acetate as well as two propionates: methyl propionate and ethyl propionate, have been determined using vacuum-ultraviolet photoelectron spectroscopy. These experimental investigations are complemented by ab initio calculations. The measured first adiabatic and vertical ionization energies...
-
The new concept of capillary forces aided evaporator for application in domestic organic rankine cycle
PublikacjaThis paper presents studies on the possibility of applying capillary forces induced in the porous structure to a modern design of evaporator. The potential application of such heat exchanger is for example an evaporator of the domestic micro combined heat and power (CHP) unit. One of the problems in the micro-CHP is excessive demand for pumping power. The proposed design helps in overcoming that issue. In the evaporator outlined...
-
Modeling of natural convection with Smoothed Particle Hydrodynamics: Non-Boussinesq formulation
Publikacja -
Temperature, velocity and mean turbulence structure in strongly heated internal gas flows. Comparison of numerical predictions with data
PublikacjaW pracy przedstawiono symulacje numeryczne przy użyciu szeregu modeli turbulencji celem analizy silnie ogrzewanego przepływu powietrza w pionowych rurach. Obliczenia porównano z danymi eksperymentalnymi. Analizowano modyfikacje pola prędkości, temperatury i turbulencji. W rozpatrywanych warunkach odnotowano silną wrażliwość obliczeń na silnie zmieniające się pole temperatury. Stwierdzono, że analizowane przypadki najlepiej odzwierciedla...
-
Experimental and numerical study of thermal and electrical potential of BIPV/T collector in the form of air-cooled photovoltaic roof tile
PublikacjaAmong renewable energy sources, Building-Integrated Photovoltaic/Thermal (BIPV/T) systems are gaining increasing interest. To improve their economic competitiveness, technologies that increase their efficiency are searched for. The paper is devoted to evaluating the impact of various air-cooling configurations on the thermal and electrical performance of a photovoltaic roof tile. A numerical model of the own experimental system...
-
Study on effective front region thickness of PCM in thermal energy storage using a novel semi-theoretical model
PublikacjaThermal energy storage in mobile applications, particularly battery of electric vehicles, is currently gaining a lot of importance. In this paper, a semi-theoretical time-dependent mathematical model of the phase change in a double shell thermal energy storage module has been developed where the inner tube is a heat exchange surface. An effective front region thickness for the melting and solidification process has been studied....
-
Jeffreys heat conduction in coupled semispaces subjected to interfacial heating
PublikacjaA Jeffreys heat conduction problem for coupled semispaces subjected to the action of an interfacial heat source was defined. An analytical solution of the problem was derived for a polynomial specific power of the heat source using the Laplace transform approach. The asymptotic and parametric analysis was performed for different ratios of thermal conductivities , thermal diffusivities , thermal relaxation times and coefficients...
-
Optimization of the femtosecond laser impulse for excitation and the Spin-Orbit mediated dissociation in the NaRb Dimer
PublikacjaWe study the dynamics of multiple coupled states under the influence of an arbitrary time-dependent external field to investigate the femtosecond laser-driven excitation and the spin-orbit mediated dissociation in the NaRb dimer. In this process, the dimer is excited from the ground triplet state 1^3Sigma+ to the 1^3Pi state using the femtosecond laser impulse and the spin-orbit coupling between the 1^3Pi and 2^1Sigma+ states results...
-
Perfect thermal contact of hyperbolic conduction semispaces with an interfacial heat source
PublikacjaThe problem of thermal contact between two bodies with a heat source at their interface presents great scientific and practical interest. On the time scale of a nanosecond or shorter, heat propagation should be considered in the form of thermal waves of finite speeds. This study investigated the thermal behaviour of hyperbolic conduction semispaces in perfect thermal contact subjected to the action of an interfacial heat source....
-
Marek Biziuk prof. dr hab. inż.
OsobyUr. 25.06.1947 w Sokółce, Województwo Podlaskie. W latach 1964-1969 studiował na Wydziale Chemicznym PG. Stopień doktora nauk technicznych uzyskał w 1977 r., a stopień doktora habilitowanego nauk chemicznych w zakresie chemia uzyskał na Wydziale Chemicznym PG 24.05.1995 r. Tytuł naukowy profesora nauk chemicznych uzyskał na Wydz. Chemicznym PG 6.04.2001 r. Członek Komitetu Chemii Analitycznej PAN od 2008, członek Zespołu ds....
-
Application of nanofluids in thermal technologies
PublikacjaNanofluids it is a relatively new category of thermal fluids that can serve as coolants, both in single- and two phase systems. However application of nanofluids in industrial applications requires faultless their thermophysical properties. Existing models originally developed for liquid/solid particles mixtures (slurries) fail in case of nanofluids. Moreover correlations used to calcuate heat transfer coefficients of conventional...
-
Performance of the domestic micro ORC equipped with the shell-and-tube condenser with minichannels
PublikacjaIn this paper, the original compact shell-and-tube heat exchanger with circular minichannels of in-house design and manufacturing is presented as the condenser for the domestic micro heat and power plant investigations as well as other future technical applications. The heat exchanger is equipped with turbulizing baffles inside the shell. The shell itself is made of a tubular sleeve having an inner diameter of 0.067 m and the length...
-
MHD Casson flow across a stretched surface in a porous material: a numerical study
PublikacjaIn this study, we examine the nature of magnetohydrodynamic (MHD) Casson flow of fluid across a stretched surface in a porous material. It studies how the behaviour of Casson fluids is affected by a number of variables, including thermal radiation, chemical processes, Joule heating, and viscosity dissipation. The Keller box strategy, based on the finite difference method (FDM), is used to tackle the complex numerical problem. Graphical...
-
Assessment of the impact of jet impingement technique on the energy efficiency of air-cooled BIPV/T roof tile
PublikacjaThe paper concerns a numerical analysis of cooling of the hybrid photovoltaic (PV) modules dedicated to Building-Integrated Photovoltaic/Thermal (BIPV/T) systems. Attention was focused on the photovoltaic roof tiles, using a jet impingement technique, in which the intensification of heat transfer is ensured by streams of air hitting the heat exchange partition. A series of numerical simulations were carried out to assess an influence...
-
Mini Light-Emitting Diode Technology with High Quantum Efficient NIR-II Partially Inverse Spinel MgGa2O4:Cr3+,Ni2+ Nanophosphors
Dane BadawczeThe increasing demand for second near-infrared (NIR-II) region materials, which retain the advantage of minimal scattering and immense applications in the medical and NIR spectroscopy field, has led to considerable research in this region. A mini light-emitting diode (mini-LED) is essential for backlighting liquid crystal displays, indicating the need...
-
XRD pattern of Mo2Ga2C, Mo2CTx/Mo2GaC and Ni-Mo2CTx/Mo2Ga2C materials
Dane BadawczeIn the dataset are included raw data for the preparation of XRD pattern of Mo2Ga2C, Mo2CTx/Mo2GaC and Ni-Mo2CTx/Mo2Ga2C materials.
-
Chemically Selective Alternatives to Photoferroelectrics for Polarization-Enhanced Photocatalysis: The Untapped Potential of Hybrid Inorganic Nanotubes
PublikacjaLinear-scaling density functional theory simulation of methylated imogolite nanotubes (NTs) elucidates the interplay between wall-polarization, bands separation, charge-transfer excitation, and tunable electrostatics inside and outside the NT-cavity. The results suggest that integration of polarization-enhanced selective photocatalysis and chemical separation into one overall dipole-free material should be possible.
-
Bariery rozwoju spółek przedsiębiorczości akademickiej
PublikacjaW opracowaniu przedstawiono zagadnienie przedsiębiorczości akademickiej. Autorzy wyodrębnili i sklasyfikowali kluczowe bariery hamujące rozwój komercjalizacji wiedzy i technologii do świata biznesu, a także ograniczające rozwój przedsiębiorczości akademickiej. Zaprezentowano wyniki badań przeprowadzonych przez Deloitte Business Consulting SA w zakresie ograniczeń wpływających na transfer technologii
-
Substrate-integrated waveguide (SIW) filter design using space mapping
PublikacjaIn this paper, we present a fast technique for an automated design of microwave filters in substrate integrated wave (SIW) technology. The proposed methodology combines the space mapping technique with a cost function defined using the location of complex zeros and poles of filter’s transfer and reflection function and uses a rectangular waveguide as a surrogate model. The effectiveness of the proposed technique is presented with...
-
Magdalena Brzozowska-Woś dr hab. inż.
OsobyMagdalena Brzozowska-Woś jest absolwentką Wydziału Zarządzania i Ekonomii Politechniki Gdańskiej (specjalność: systemy zarządzania). Jest również absolwentką Podyplomowego Studium Reklamy (Wydział Zarządzania i Ekonomii PG) oraz Podyplomowego Studium Public Relations (SWPS Uniwersytet Humanistycznospołeczny). W latach 2000-2003 współpracowała z Panoramą Internetu sp. z o. o. jako specjalista ds. marketingu. Pełniła również obowiązki...
-
Implementacja w technologii radia programowalnego transceivera opartego na technice OFDM pracującego w trybie dupleksu czasowego
PublikacjaTechnika OFDM jest obecnie jedną z najbardziej popularnych metod realizacji szybkiej transmisji danych w warstwie fizycznej współczesnego systemu radiokomunikacyjnego. Choć jej wykorzystanie w technologii radia programowalnego w celu realizacji jednokierunkowej transmisji jest dość powszechne, to wciąż trudno znaleźć przykłady implementacji łączy dwukierunkowych czasu rzeczywistego, w szczególności tych opartych na trybie dupleksu...
-
Wprowadzenie do zarządzania wiedzą
PublikacjaPrzedstawiono różne definicje zarzšdzania wiedzš, porównano strategię kodyfikacji i personalizacji,opisano transfer wiedzy w przedsiębiorstwie oraz szeroko omówino bariery wdrażania zarzšdzania wiedzš. W dalszej częci starano się udowodnić tezę, że przekształcanie przedsiębiorstw w organizacje wiedzy jest szansš dla osób 50+ przedstawiajšc model takiej organizacji.
-
LCT, PIV and IR Imaging Detection in Selected Technical and Biomedical Applications
PublikacjaPaper presents the brief summary of the history of Thermochromic liquid crystals (TLC), Particle Image Velocimetry (PIV) and Infrared Imaging Themography (IR). Principal methods and tools are described and some examples are presented. With this objective, a new experimental technique have been developed and applied to the study of heat and mass transfer and for biomedical diagnosis. Selected results of experiments using these methods...
-
Technology of an adhesive silicone film as drug carrier in transdermal therapy I. Analytical methods used for characterization and design of the universal elastomer layers
PublikacjaSilicone polymers possess unique properties, which make them suitable for many different applications, for example in the pharmaceutical and medical industry. To create an adhesive silicone film, the appropriate silicone components have to be chosen first. From these components two layers were made: an adhesive elastomer applied on the skin, and a non-adhesive elastomer on the other side of the film. The aim of this study was...
-
Optimization of the Relative Humidity of Reactant Gases in Hydrogen Fuel Cells Using Dynamic Impedance Measurements
PublikacjaWater management is a key factor affecting the efficiency of proton exchange membrane fuel cells (PEMFCs). The currently used monitoring methods of PEMFCs provide limited information about which processes or components that humidity has a significant impact upon. Herein, we propose the use of a novel approach of impedance measurements using a multi-sinusoidal perturbation signal, which enables impedance measurements under dynamic...
-
Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublikacjaThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
-
Modeling two phase flow in large scale fractured porous media with an extended multiple interacting continua method
PublikacjaWe present a two phase flow conceptual model, the corresponding simulator (2pMINC) and a workflow for large-scale fractured reservoirs, based on a continuum fracture approach which uses the multiple interacting continua (MINC) method complemented with an improved upscaling technique. The complex transient behavior of the flow processes in fractured porous media is captured by subgridding the coarse blocks in nested volume elements...
-
Non-destructive inspection of ground anchors using guided wave propagation
PublikacjaThis paper deals with numerical and experimental investigations of specific problems of guided wave propagation in ground anchors. The research focuses on recognizing the phenomenon of the energy transfer between anchor components. Particular attention is paid to characteristic features of guided waves propagating in free and embedded parts of the tendon, at the interface between the tendon and the surrounding anchor body as well...
-
Comparative study of a bottoming SRC and ORC for Joule–Brayton cycle cooling modular HTR exergy losses, fluid-flow machinery main dimensions, and partial loads
PublikacjaEnergy conversion efficiency increase in power plants with high-temperature gas-cooled reactors via implementation of the bottoming cycle was investigated under nominal and minimal thermal load of a high-temperature reactor (HTR). Heat transfer surface area and turbine outlet volumetric flow rate in bottoming cycles was also investigated. Water and two low-boiling point working fluids (ammonia and ethanol) were analyzed. Analyzed...
-
Rheology of Variable Viscosity‐Based Mixed Convective Inclined Magnetized Cross Nanofluid with Varying Thermal Conductivity
PublikacjaCross nanofluid possesses an extraordinary quality among the various fluidic models to explore the key characteristics of flowing fluid during very low and very high shear rates and its viscosity models depend upon shear rate. The current study establishes the numerical treatment regarding variable viscosity‐based mixed convective inclined magnetized Cross nanofluid with var‐ ying thermal conductivities over the moving permeable...
-
High catalytic performance of laccase wired to naphthylated multiwall carbon nanotubes
PublikacjaThe direct electrical connection of laccase on the electrode surface is a key feature in the design of efficient and stable biocathodes. However, laccases can perform a direct electron transfer only when they are in the preferable orientation toward the electrode. Here we report the investigation of the orientation of Laccase from Amano on multi-walled carbon nanotube surface modified with naphthalene group. Naphthylated multi...
-
Understanding the interactions between protein stabilizers and the peptide bond through the analysis of the volumetric and compressibility properties for the model systems
PublikacjaThis work confirms our earlier supposition, that volumetric and acoustic parameters for simple model proposed by us are directly related to stabilizing/destabilizing effect of osmolytes on proteins structure. The apparent molar volumes, V and the apparent molar isentropic compressions, KS,, of glycine and N,N,N –trimethylglycine (betaine) were determined from densities and speed of sound measurements in aqueous solution of N-methylacetamide...
-
Visible-light-driven lanthanide-organic-frameworks modified TiO2 photocatalysts utilizing up-conversion effect
PublikacjaHighly efficient and quite stable composite with core-shell-like architecture reported herein, responds to the challenge of sunlight-driven photocatalysts. The Ln(ndc)/TiO2 photocatalytic system comprises active lanthanide-carboxylate coordination networks (Nd, Er, Ho, and Tm as metal ions, and 2,6-naphthalene dicar-boxylic acid as the organic linker) and inert titanium dioxide and allow to convert incompatible visible radiation...
-
Magneto-thermal convection of low concentration nanofluids
PublikacjaThe main aim of this paper was to analyze possible utilization of the low concentration nanofluids and the magnetic field to enhance heat transfer. The studied fluids were based on water with an addition of copper particles (40-60 nm diameter). They belonged to the diamagnetic group of materials. As a first attempt to stated target the analysis of enclosure placed in the maximal value of square magnetic induction gradient was carried...
-
Forecasting of railway track tamping based on settlement of sleepers using fuzzy logic
PublikacjaThe sleepers in a railway track transfer vertical, transverse and longitudinal loads to the track ballast and subgrade. The sleepers allow for keeping the distance between the rails constant. The thickness of ballast should be between 16 and 35 cm depending on the design standard of the track, and it should be densified where the ballast supports the sleeper. The exploitation causes contamination of the ballast, crushing the material...
-
Mechanical Properties of Twisted Carbon Nanotube Bundles with Carbon Linkers from Molecular Dynamics Simulations
PublikacjaThe manufacturing of high-modulus, high-strength fibers is of paramount importance for real-world, high-end applications. In this respect, carbon nanotubes represent the ideal candidates for realizing such fibers. However, their remarkable mechanical performance is difficult to bring up to the macroscale, due to the low load transfer within the fiber. A strategy to increase such load transfer is the introduction of chemical linkers...
-
Anaerobic consortia mediate Mn(IV)-dependent anaerobic oxidation of methane
PublikacjaManganese-dependent anaerobic oxidation of methane (Mn-AOM) is a major methane sink and vital to mitigating global warming. However, it is difficult for microorganisms to mediate electron transfer between the hardly dissolved CH4 and insoluble Mn(IV) minerals, leading to poor understanding of species mediating Mn-AOM. This study successfully enriched an anaerobic consortium mediating AOM driven by Mn-dependent respiratory growth,...
-
Efficient bounds on quantum-communication rates via their reduced variants
PublikacjaWe investigate one-way communication scenarios where Bob operating on his component can transfer some subsystem to the environment. We define reduced versions of quantum-communication rates and, further, prove upper bounds on a one-way quantum secret key, distillable entanglement, and quantum-channel capacity by means of their reduced versions. It is shown that in some cases they drastically improve their estimation.
-
Modelling of Graphene Field-Effect Transistor for lectronic sensing applications
PublikacjaA top-gated Graphene Field-Effect Transistor (GFET) suitable for electronic sensing applications was modelled. The applied simulation method reproduces correctly the output transfer GFET characteristics and allows to investigate doping effect caused by different physical, chemical or biological factors. The appearance of additional charge in the system results in the shift of the current-voltage characteristic. This feature could...
-
Imaging of biological samples: crassula arborescens
Dane BadawczeOne of the tasks of modern botany is to describe the relationship between climatic conditions and other environmental factors and the anatomical structure and adaptation of species present in given geographic areas. The work [1] focuses on anatomical and morphological studies of leaves of plants from the coarse family. Species tested belong to leaf...
-
Improved finite element method for flow, heat and solute transport of Prandtl liquid via heated plate
PublikacjaIn the current study, a vertical, 3D-heated plate is used to replicate the generation of heat energy and concentration into Prandtl liquid. We discuss how Dufour and Soret theories relate to the equations for concentration and energy. In order to see how efectively particles, interact with heat and a solvent, hybrid nanoparticles are used. It does away with the phenomena of viscous dissipation and changing magnetic felds. The motivation...
-
Dendron to Central Core S1–S1 and S2–Sn (n>1) Energy Transfers in Artificial Special Pairs Containing Dendrimers with Limited Numbers of Conformations
PublikacjaTwo dendrimers consisting of a cofacial free-base bisporphyrin held by a biphenylene spacer and functionalized with 4-benzeneoxomethane (5-(4-benzene)tri-10,15,20-(4-n-octylbenzene)zinc(II)porphyrin) using either five or six of the six available meso-positions, have been synthesized and characterized as models for the antenna effect in Photosystems I and II. The presence of the short linkers, -CH2O-, and long C8H17 soluble side...
-
Natural convection in symmetrically heated vertical channels
PublikacjaThe study describes natural convection through a vertical channel, open on four sides and bound by two isothermal walls. Both balancing and infrared experimental investigations were performed in air (Pr = 0.71) to estimate the impact of channel width s and wall-to-ambient temperature difference (tw - t∞) on natural convective heat transfer, the formation of air flow patterns and the rate of flow pattern formation. The study was...
-
Analysis and Evaluation of the Working Cycle of the Diesel Engine
PublikacjaThe paper presents a proposal to apply a quantitative evaluation of the diesel engine with regard to the phenomena occurring during of a working cycle. The proposed procedure when analyzing test results from diesel engine is an attempt to transfer an engine activity evaluation methods in the operational time scale (exploit time), eg. in hours, to the micro-scale (dynamic time) relating only to the execution time of one (several)...
-
The Effect of Posaconazole, Itraconazole and Voriconazole in the Culture Medium on Aspergillus fumigatus Triazole Resistance
PublikacjaTriazoles are the only compounds used as antibiotics in both medicine and agriculture. The presence of triazoles in the environment can contribute to the acquisition of azole resistance among isolates of Aspergillus fumigatus. The objective of this study was to investigate the effect of A. fumigatus exposure to triazoles on susceptibility to these compounds. Seventeen triazole-resistant and 21 triazole-sensitive A. fumigatus isolates...