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Search results for: PROTON TRANSFER REACTION
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4-[(tert-Butyldimethylsilyl)oxy]-6-methoxy-7-methyl-5-(oxiran-2-ylmethyl)-2-benzofuran-3(1H)-one
PublicationThe title compound, C19H28O5Si, was obtained in the reaction of 1,3-dihydro-4-[(tert-butyldimethylsilyl)oxy]-6-methoxy-7-methyl-3-oxo-5-(prop-2-enyl)isobenzofuran with meta-chloroperbenzoic acid. This reaction is one of the stages of the total synthesis of mycophenolic acid, which we attempted to modify. The title compound forms crystals with only weak intermolecular interactions. The strongest stacking interaction is found between...
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Studies on the formation of formaldehyde during 2-ethylhexyl 4-(dimethylamino)benzoate demethylation in the presence of reactive oxygen and chlorine species
PublicationIn order to protect the skin from UV radiation, personal care products (PCPS) often contain chemical UV-filters. These compounds can enter the environment causing serious consequences on the water ecosystems. The aim of this study was to examine, the effect of different factors, such as UV light, the presence of NaOCl and H2O2 on the formaldehyde formation during popular UV filter, 2-ethylhexyl 4-(dimethylamino)benzoate (ODPABA)...
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Increased concentration of Taq DNA polymerase as a solution for GC-rich templates from clinical and environmental samples
PublicationDNA polymerase is an enzyme which plays crucial role in replication and DNA repair. It found application in PCR (polymerase chain reaction) where catalyses process of in vitro DNA synthesis. To meet the demands posed by mod- ern diagnostic, molecular biology or genetic engineering it is necessary to improve DNA polymerases to obtain new or better features useful in these fields. So far implemented modifications in majority are...
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In-Out Surface Modification of Halloysite Nanotubes (HNTs) for Excellent Cure of Epoxy: Chemistry and Kinetics Modeling
PublicationIn-out surface modification of halloysite nanotubes (HNTs) has been successfully performed by taking advantage of 8-hydroxyquinolines in the lumen of HNTs and precisely synthesized aniline oligomers (AO) of different lengths (tri- and pentamer) anchored on the external surface of the HNTs. Several analyses, including FTIR, H-NMR, TGA, UV-visible spectroscopy, and SEM, were used to establish the nature of the HNTs’ surface engineering....
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WYKORZYSTANIE INNOWACYJNEJ METODYKI STUDIUM PRZYPADKU W EDUKACJI BIZNESOWEJ – PROJEKT INNOCASE, LdV, TOI
PublicationNiniejszy artykuł przedstawia jeden z projektów dydaktycznych realizowanych w ramach programu Leonardo da Vinci, Transfer of Innovations. Projekt ten nosi tytuł INNOCASE – Transfer innowacyjnej metodyki studium przypadku w edukacji biznesowej. W artykule można znaleźć informacje na temat genezy powstania projektu, jego celów, grup docelowych, konsorcjum realizującego projekt, metodologii i planu pracy, a także znaczenia projektu...
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Thermal Energy Development in Magnetohydrodynamic Flow Utilizing Titanium Dioxide, Copper Oxide and Aluminum Oxide Nanoparticles: Thermal Dispersion and Heat Generating Formularization
PublicationThe main aim of this article heat transfer in thermal engineering deals with the production, use, transformation, and transfer of thermal energy. Engineering and industrial fields including food packaging, the production of food additives, electronic cooling, microturbines, etc. heavily rely on heat transmission. Due to its intriguing potential in industries like the production of polymers, paper, crystal glass, etc., scientists...
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Agnieszka Kania Mgr
PeopleUkończyła WZIE PG - kierunek Zarządzanie i Marketing o specjalności Ekonomia i Finanse. Posiada kilkunastoletnie doświadczenie we współpracy z otoczeniem biznesowym. Pierwsze kroki w biznesie stawiała na stanowisku Analityka Finansowego, Doradcy Klienta Biznesowego, następnie zdobywała doświadczenie na stanowiskach manadżerskich rekrutując i budując zespoły jako Kierownik Zespołu w korporacji finansowej, negocjując kontrakty,...
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Conformation analysis and semiclassical dynamics study of charge exchange process induced by collision of C2+ ions with tetrahydrofuran
PublicationWe present the results of recent investigations of charge transfer processes in the collisions of C²⁺ ions with heterocyclic molecules of tetrahydrofuran.
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Standing Waves and Acoustic Heating (or Cooling) in Resonators Filled with Chemically Reacting Gas
PublicationStanding waves and acoustic heating in a one-dimensional resonator filled with chemically reacting gas, is the subject of investigation. The chemical reaction of A ! B type, which takes place in a gas, may be reversible or not. Governing equations for the sound and entropy mode which is generated in the field of sound are derived by use of a special mathematical method. Under some conditions, sound waves propagating in opposite...
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Syntheses, spectroscopic and structural properties of phenoxysilyl compounds: X-ray structures, FT-IR and DFT calculations
PublicationThe reaction of silicon disulfide with alkylphenols leads to tetraphenoxysilane, cyclodisilthiane and silanethiol. The products of the reaction of silicon disulfide with phenols are characterized by FT-IR, NMR, X-ray diffraction and DFT calculations. The intramolecular interactions in the compounds are mainly XH---π (X = C, S) whereas the intermolecular interactions are either very weak CH---π/CH---O contacts found in aryloxysilane...
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Microwave-assisted synthesis of zinc derivatives of potato starch
PublicationZincatated potato starch was prepared in a solid-state, microwave-assisted reaction using generated in situ sodium tetrahydroxozincate [Na2Zn(OH)4]. For comparison, zincatation of starch was also carriedout on convectional heating. Depending on the irradiation conditions, the products of either mono- or crosslinking esterification were formed. Higher power applied at shorter exposition offered products ofmonoesterification, and...
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Multi-nodal PWR reactor model — Methodology proposition for power distribution coefficients calculation
PublicationIn the paper the multi-nodal Pressurized Water Reactor (PWR) model called Mann’s model is presented. This models is used for modelling purposes of the heat transfer from fuel to coolant in reactor core. The authors expand widely used in literature approach by defining additional coefficients for the heat transfer model. These parameters approximate the power generation distribution in the PWR reactor core according to the to the...
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Numerical Modelling of Forced Convection of Nanofluids in Smooth, Round Tubes: A Review
PublicationA comprehensive review of published works dealing with numerical modelling of forced convection heat transfer and hydrodynamics of nanofluids is presented. Due to the extensive literature, the review is limited to straight, smooth, circular tubes, as this is the basic geometry in shell-and-tube exchangers. Works on numerical modelling of forced convection in tubes are presented chronologically in the first part of the article....
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Hopping or Tunneling? Tailoring the Electron Transport Mechanisms through Hydrogen Bonding Geometry in the Boron-Doped Diamond Molecular Junctions
PublicationMechanisms of charge transport in molecular junctions involving hydrogen bonds are complex and remain mostly unclear. This study is focused on the elucidation of the electron transfer in a molecular device consisting of two boron-doped diamond interfaces bound with an aromatic linker and a hydrogen bonding surrogating molecule. The projected local density of states (PLODS) analysis coupled with transmission spectra and current−voltage...
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Port-Based Modelling of Distributed-Lumped Parameter Systems
PublicationThere in the paper is presented an uniform, port-based approach to modelling of both lumped and distributed parameter systems. Port-based model of the distributed system has been defined by application of bond graph methodology and distributed transfer function method (DTFM). The approach proposed combines versatility of port-based modelling and accuracy of distributed transfer function method. The concise representation of lumped-distributed...
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Physical Chemistry_GTM_20_21_winter
e-Learning CoursesThe aim of the subject is to familarize the student with fundamental physico-chemical laws in chemical thermodynamics, phase equilibria and chemical equilibria together with ability of solving relevant text problems involving calculations, as well as teachnig him/her effective and safe carrying out simple experiments/measurements of physico-chemical quantities and proper presentation and interpretation of their results. LECTURES Chemical...
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Thermal and economic investigation of straight and U-bend double tube heat exchanger with coiled wire turbulator
PublicationExperimental research has been carried out for four individual heat exchanger constructions, i.e., plain double tube, turbulized double tube, plain U-bend and U-bend with turbulator. Tests were made for the water-water system. The study covered a wide measuring range, i.e., Re = 800–9000 – on the shell side, for a constant cold water temperature of 9 ◦C and hot water of 50 ◦C. The heat exchangers were made from copper tubes with...
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Thermal Energy Storage with PCMs in Shell-and-Tube Units: A Review
PublicationThe paper presents a survey of the experimental and numerical studies of shell-and-tube systems in which phase change material (PCM) is used. Due to the multitude of design solutions for shell-and-tube systems, the emphasis is placed on double-tube (DT), triplex-tube (TT), and multitube (MT) units. Additionally, only single-pass systems are considered. Particular attention is paid to the method of heat transfer intensification....
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Mono- and bimetallic nanoparticles decorated KTaO 3 photocatalysts with improved Vis and UV–Vis light activity
PublicationNew mono- and bimetallic nanoparticle-decorated perovskite-type KTaO3 photocatalysts were successfully synthesized by hydrothermal reaction followed by photodeposition of MNPs/BNPs. The effect of noble metal type, amount of metal precursor as well as photoreduction method on the physicochemical and photocatalytic properties of MNPs- and BNPs-KTaO3 have been investigated. Photocatalytic activity under Vis light irradiation was estimated...
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Decahedral-shaped anatase titania photocatalyst particles: Synthesis in a newly developed coaxial-flow gas-phase reactor
PublicationDecahedral-shaped anatase particles (DAPs) were prepared by a gas-phase process consisting of titanium(IV) chloride oxidation. The use of a coaxial-flow gas-phase reactor resulted in high reaction yield (ca. 70%) and good reproducibility of DAPs production. The influence of controlled and resultant preparation parameters on the process course and on DAPs properties (such as specific surface area, particle size and particle morphology)...
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Microwave radiation in the synthesis of urethane prepolymers
PublicationThis paper describes the use of microwave radiation in the synthesis of urethane prepolymers in bulk (without solvent). The prepolymers were synthesized using 1,6-hexamethylene diisocyanate (HDI) and poly (ε-caprolactone) diol (PCL) at a molar ratio of 4:1. The reaction was carried out without a catalyst in the reactor with a conventional heating system (oil bath) or in the microwave reactor (MW Reactor NOVA 09) at temperatures...
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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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First highly effective non-catalytic nitrobenzene reduction in UV/dithionite system with aniline production – Advanced reduction process (ARP) approach
PublicationAdvanced reduction processes (ARPs) are currently intensively investigated as an alternative to Advanced Oxidation Processes (AOPs). The study presents efficient reduction of nitrobenzene under non-catalytic conditions through reaction with free radicals having reductive potential. Effective conversion of nitrobenzene in a model wastewater solution, was obtained for sodium dithionite (SDT)/ dithionite (DTN). The developed process...
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EXPERIMENTAL INVESTIGATION OF FREE CONVECTION OF GLYCOL-Al2O3 NANOFLUID FROM HORIZONTAL TUBE
PublicationNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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Experimental investigation of free convection of glycol-Al2O3 nanofluid from horizontal tube
PublicationNanofluids came to be seen as a new generation of coolants, both in single- and two phase systems. Furthermore, nanofluids or nanocomposites may be used as a media in a thermal energy storage (TES) in such systems as sensible heat storage (SHS) and phase change materials (PCM). In the SHS systems the dominating mechanism of the heat transfer is natural convection. However, in the literature only a few investigations of free convection...
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An Extended Control of the Input Angle for Matrix Converters Connected with the Non-Unity Power Factor Loads.
PublicationThis paper proposes a novel PWM modulation algorithm for Multiphase Conventional Matrix Converters (MCMC), with 3 inputs and k outputs, using the transfer function of the load angle. The proposed approach extends the range of power angle control at the input during the operation with a maximum voltage transfer ratio. The proposed concept is based on the Direct Analytic Voltage PWM (DAV--PWM) modulation with an elliptical trajectory...
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Impact of strontium non-stoichiometry of SrxTi0.3Fe0.7O3-δ on structural, electrical, and electrochemical properties for potential oxygen electrode of intermediate temperature solid oxide cells
PublicationThis work presents the results of a comprehensive study on the impact of the A-site non-stoichiometry of SrxTi0.3Fe0.7O3-δ (x = 0.90, 0.95, 1.00, 1.05) ceramics on their physicochemical properties. The materials were fabricated by the conventional solid-state reaction method and their structure was determined by X-ray diffractometry, X-ray photoelectron spectroscopy and electron microscopy. Their sintering and thermal expansion...
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Phosphinophosphoranes: Mixed-Valent Phosphorus Compounds with Ambiphilic Properties
PublicationHerein, we present a simple synthesis of mixed-valent phosphinophosphoranes bearing three- and five-coordinate phosphorus centers. Compounds with phosphorus–phosphorus bonds were synthesized via a reaction of lithium phosphides RR′PLi with cat2PCl (cat = catecholate), whereas derivatives with methylene-linked phosphorus centers were obtained via a reaction of phosphanylmethanides RR′CH2Li with cat2PCl. The presence of accessible...
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Recuperator with microjet technology as a proposal for heat recovery from low-temperature sources
PublicationA tendency to increase the importance of so called dispersed generation, based on the local energy sources and the working systems uti- lizing both the fossil fuels and the renewable energy resources is observed nowadays. Generation of electricity on industrial or domestic scale together with production of heat can be obtained for example through employment of the ORC systems. It is mentioned in the EU directive 2012/27/EU for...
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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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Koncepcja doskonalenia marketingu nowych technologii w Politechnice Gdańskiej
PublicationW rozdziale podjęto problem doskonalenia wykorzystania dorobku współczesnego marketingu w przygotowaniu i oferowaniu nowych technologii, oparte na doświadczeniach Politechniki Gdańskiej (PG). Omówiono pojęcia, cechy, korzyści i uwarunkowania współczesnego marketingu, jak też istoty nowych technologii i sposobów transferu z jednostek naukowo-badawczych do gospodarki. Przedstawiono dotychczasowe doświadczenia transferu i komercjalizacji...
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Unusual streaming in chemically reacting gases
PublicationNonlinear stimulation of the vorticity mode caused by losses in the momentum of sound in the chemically reacting gas, is considered. The instantaneous dynamic equation which describes the nonlinear generation of the vorticity mode, is derived. It includes a quadratic nonlinear acoustic source. Both periodic and aperiodic sound may be considered as the origin of the vorticity flow. In the non-equilibrium regime of the chemical reaction,...
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Transition-Metal-Promoted Oxidative Cyclization To Give 1,2,4-Trisubstituted Carbazole Scaffolds
PublicationHerein, we describe the synthesis of a 1,2,4-trisubstituted carbazole core from 5-(1H-indol-3-yl)-3-oxopentanoic acid esters or amides. For oxidative cyclization, we tested two different approaches. First, we used manganese triacetate as a conventional moderate oxidizer to ensure the radical course of the reaction. Second, we examined the use of a more complex oxidizing agent I2/Me(OTf)3. In both cases, formation of a fused-ring...
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Piotr Grudowski dr hab. inż.
PeopleProfessor Dr hab. Eng. Piotr Grudowski heads the Department of Quality and Commodity Management at the Faculty of Management and Economics of Gdansk University of Technology. In the years 1987-2009 he worked at the Faculty of Mechanical Engineering of the Gdansk University of Technology, where he obtained a doctoral degree in technical sciences in the discipline of construction and operation of machines and he headed the Department...
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Singlet oxygen in the removal of organic pollutants: An updated review on the degradation pathways based on mass spectrometry and DFT calculations
PublicationThe degradation of pollutants by a non-radical pathway involving singlet oxygen (1O2) is highly relevant in advanced oxidation processes. Photosensitizers, modified photocatalysts, and activated persulfates can generate highly selective 1O2 in the medium. The selective reaction of 1O2 with organic pollutants results in the evolution of different intermediate products. While these products can be identified using mass spectrometry...
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Enhanced photocatalytic activity of accordion-like layered Ti3C2 (MXene) coupled with Fe-modified decahedral anatase particles exposing {1 0 1} and {0 0 1} facets
PublicationNew composites consisting of decahedral anatase particles exposing {001} and {101} facets coupled with accordion-like layered Ti3C2 with boosted photocatalytic activity towards phenol and carbamazepine degradation were investigated. The photocatalysts were characterized with X-ray diffraction (XRD), diffuse reflectance spectroscopy (DR/UV–Vis), Brunauer-Emmett-Teller (BET) specific surface area, Raman spectroscopy, scanning electron...
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Voltage Harmonic Distortion Measurement Issue in Smart-Grid Distribution System
PublicationThis paper presents the investigation results ofvoltage harmonic transfer accuracy problems through voltagetransformers which are widely used in power quality monitoringsystems in medium and high voltage grids. A simplified lumpedparameters circuit model of the voltage transformer is presentedand verified by simulation and experimental investigations. Anumber voltage transformers typically used in medium voltagegrid has been tested...
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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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Techniki biologii molekularnej w analityce produktów mięsnych
PublicationW pracy przedstawiono możliwości wykorzystania reakcji PCR (Polymerase Chain Reaction) do identyfikacji patogennych drobnoustrojów a także do badania składu surowcowego w mięsnych produktach żywnościowych.
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Reactivity of Phosphanylphosphinidene Complex of Tungsten(VI) toward Phosphines: A New Method of Synthesis of catena-Polyphosphorus Ligands
PublicationThe reactivity of an anionic phosphanylphosphinidene complex of tungsten(VI), [(2,6-i-Pr2C6H3N)2(Cl)- W(η2-t-Bu2P=P)]Li·3DME toward PMe3, halogenophosphines, and iodine was investigated. Reaction of the starting complex with Me3P led to formation of a new neutral phosphanylphosphinidene complex, [( 2,6-i-Pr2C6H3N)2(Me3P)W(η2-t-Bu2P=P)]. Reactions with halogenophosphines yielded new catena-phosphorus complexes. From reaction with...
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Copper and copper-manganese 1D coordination polymers: Synthesis optimization, crystal structure and preliminary studies as catalysts for Baylis–Hillman reactions
PublicationThis work reports the influence of experimental parameters (pH and counter-ion) in the synthesis of the 1D coordination polymer [Cu(IDA)(H2O)2]n (IDA = iminodiacetate), named here Cu-IDA. Copper-manganese bimetallic coordination polymers were also obtained by isomorphic replacement into Cu-IDA structure, with different molar ratio of Cu2+ and Mn2+ ions, denoted here as Cu/Mn-IDA (0.9/0.1; 0.7/0.3 and 0.5/0.5). New coordination...
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International Trade winter 2022
e-Learning CoursesMain aim of the subject is to transfer knowledge on theoretical and empirical aspects of international trade. During the lectures we will cover patterns of international trade, main models of international trade and topics related to trade policy. During labs students will analyze current issues concerning trade flows in globalized world economy.
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International Trade - winter 2023
e-Learning CoursesMain aim of the subject is to transfer knowledge on theoretical and empirical aspects of international trade. During the lectures we will cover patterns of international trade, main models of international trade and topics related to trade policy. During labs students will analyze current issues concerning trade flows in globalized world economy.
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Optoelectronic properties of curved carbon systems
PublicationSystematic investigation of optoelectronic properties of curved carbon systems has been performed and the results have been compared with the representatives of flat carbon systems. Moreover, the application of third order dispersion corrected density functional tight binding method (with third order corrections of self-consistent charges) including Becke-Johnson dumping (DFTB3-D3(BJ)) has been validated in order to obtain reliable...
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Spinning Fluids Reactor: A new design of a gas – liquid contactor
PublicationCurrent trends in chemical reactor design are based on adapting these to the requirements of a particular chemical process. Processes involving reactions between the gas and liquid phase in particular require precise adjustment of all parameters. The common denominator for most modern design solutions is enhancement of the mass transfer area and the overall volumetric mass transfer coefficient. Gas – liquid contactors evolved from...
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Flow boiling of R1233zd(E) in a 3 mm vertical tube at moderate and high reduced pressures
PublicationThe results of flow boiling of R1233zd(E) in a 3 mm vertical stainless steel tube are presented at moderate and high saturation temperatures. Integral flow characteristics in the form of pressure drop and heat transfer coefficient are discussed for saturation temperatures ranging from 115 to 145 °C (corresponding reduced pressures from 0.2 to 0.7), mass velocity of 800 kg/m2s and heat flux of 20 kW/m2. All of the obtained heat...
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PRESSURE DROP OF HFE7000 AND HFE7100 IN FLOW CONDENSATION IN MINICHANNELS WITH ACCOUNT OF NON-ADIABATIC EFFECTS
PublicationFlow boiling and flow condensation are often regarded as two opposite or symmetrical phenomena involving the change of phase. There is a temptation to describe both these phenomena with one only correlation. From amongst the structures present in flow boiling and flow condensation at least the annular flow structure seems to be mostly appropriate to the common modeling. However, the shear stress acting between vapor phase and liquid...
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Experimental validation of pressure drop models during flow boiling of R134a – effect of flow acceleration and entrainment
PublicationA crucial step to assure proficient work of power and process apparatus is their proper design. A wide array of those devices operates within boiling or condensation of the working fluid to benefit from high heat transfer rates. Two-phase flows are associated with high heat transfer coefficients because of the latent heat of evaporation and high turbulence level between the liquid and the solid surface. Predicting heat transfer...
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Thermal-Hydraulic Studies on the Shell-and-Tube Heat Exchanger with Minijets
PublicationIn this paper a patented design of a heat exchanger with minijets, with a cylindrical construction is presented. It is followed by the results of its systematic experimental investigations in the single-phase convection heat transfer mode. Based on these results, validation of selected correlations (coming from the literature) describing the Nusselt number was carried out. An assessment of the heat exchange intensification level...
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A new and convenient method for the preparation of functionalized phosphorothioates
PublicationA new and efficient method for the synthesis of alkyl and aryl phosphorothioates in high yields via the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorin-2-yl)disulfanyl derivatives with trimethyl phosphite was developed.