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The Knowledge Transfer From Headquarter to Local Subsidiaries Through Expatriates - Local Employees’ Perspective
PublicationBackground. Knowledge transfer between the HQ and subsidiary has recently been targets of increasing research interest. However, the role of expatriate managers and local staff perspective on this process has not been examined enough. Research aims. This paper has two main objectives: first to develop a conceptual framework (model) of knowledge transfer between the headquarters and local subsidiary, and second to empirically evaluate...
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The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids
PublicationAbstract: This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 um. Ethanol and water as two...
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Proton Transfer Reaction Mass Spectrometry for Plant Metabolomics
PublicationVolatile organic compounds (VOCs) emitted by plants are a valuable source of information on their growth, theirresponse to stress, and the condition of their habitat. The recent trend in the analysis of low-mass molecules ofplant origin is metabolomics, which in the context of volatiles is often referred to as volatolomics. It requires theuse of modern analytical instrumentation...
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Kinetics and thermodynamics of the reaction of iminodiacetate copper(II) complexes with 1,10-phenanthroline and 2,2′-bipyridine in aqueous, anionic, cationic and nonionic surfactants solutions
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Kinetics and mechanism of the chemically modified starches during gelatinization.
PublicationNative starch was silicated by means of microwave-assisted reactions with varying doses of reagents. Resulting products were characterized by DSC and HMR-relaxation methods. It was observed that the hydratation of the silicated starches during gelatinization decreases when compared to that of the native potato starch. The amount of unfrozen water for ungelitinizated silicated starches are less than in control samples. At the same...
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Luminescence and Luminescence Kinetics of Gd3Ga5O12Polycrystals Doped with Cr3+and Pr3+
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Nonisothermal cure kinetics of epoxy/MnxFe3-xO4 nanocomposites
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Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate
PublicationDegradation of pentoxifylline (PTX) by sodium peroxydisulfate (SPDS) assisted by UV irradiation has been investigated in deionized water. The treatment was more favorable over direct photolysis or peroxydisulfate oxidation alone. The effects of various parameters, including different dosage of oxidant agent, PTX concentration, initial solution pH levels, and the presence of inorganic ions like chloride, nitrate and carbonate have...
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Numerical Investigation of Nuclear Reactor Kinetic and Heat Transfer Fractional Model with Temperature Feedback
PublicationAbstract—In the paper, the numerical results concerning the kinetics and proposed heat exchange models in nuclear reactor based on fractional calculus are presented for typical inputs. Two fractional models are proposed and compared with the model based on ordinary derivative. The first fractional model is based on one of the generalized Cattaneo equations. The second one is based on replacing the ordinary to fractional order of...
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Heat Transfer in Adsorption Chillers with Fluidized Beds of Silica Gel, Zeolite, and Carbon Nanotubes
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Effect of the inclination angle of the condenser on the heat transfer coefficient value – experimental study
PublicationWhen considering problem of the condensation of the refrigerant in a flow inside channel, one needs to pay attention to the shape of its cross-section, the hydraulic diameter, the channel length as well as the orientation of the channel axis in space (horizontal, vertical, inclined). This paper presents an experimental study concerning the effect of the inclination angle of the condenser with a single coil pipe on the heat transfer...
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Inter-governmental Collaborative Networks for Digital Government Innovation Transfer -Structure, Membership, Operation
PublicationDigital government refers to the transformation of government organizations and their relationships with citizens, business and each other through digital technology. It entails digital innovation in processes, services, organizations, policies, etc. which are increasingly developed and tested in one country and transferred, after adaptation, to other countries. The process of innovation transfer and the underlying information...
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Characterisation of the interfacial heat transfer coefficient in hot stamping of titanium alloys
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COMPARATIVE EVALUATION OF FERRITE SHIELDING DESIGNS IN INDUCTIVE POWER TRANSFER SYSTEMS
PublicationWireless power transfer technology is becoming widespread in last few years. In comparison to conventional solutions this technology can significantly increase maintainability and safety of charging systems. From the other side there are list of factors that limit efficiency of wireless systems. One of them is low coupling between coils caused by comparably high leakage inductance in comparison to regular transformer.
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An improved method for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the paper are presented the results using the authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data to investigate the sensitivity of the in-house developed model. In the work are presented the results of calculations obtained using the semi-empirical model on selected experimental flow boiling data of the refrigerants: R134a, R1234yf,...
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Free Convection Heat Transfer from Horizontal Cylinders
PublicationThe results of experimental investigation of free convection heat transfer in a rectangular container are presented. The ability of the commonly accepted correlation equations to reproduce present experimental data was tested as well. It was assumed that the examined geometry fulfils the requirement of no-interaction between heated cylinder and bounded surfaces. In order to check this assumption recently published correlation equations...
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NEW SOLUTIONS FOR THE SOLAR CHARGE CONTROLLERS DESIGN FOR OBTAINING TRUE MPP IN PARTLY SHADED PV MODULES
PublicationSoft shading sources such as tree limbs, structural elements of buildings and chimneys, scatter and refract sunlight, significantly reducing the amount of radiation reaching the surface of the module. The hard shadings located directly on the surface (i.e. bird droppings, leaves, snow) tend to stop sunlight completely. These phenomena significantly affects the output characteristics of photovoltaic modules and often contribute...
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Evaluating the influence of radiative heat flux on convective heat transfer from a vertical plate in air using an improved heating plate
PublicationThis article examines the influence of radiative heat flux on the accuracy of the results of free convective heat transfer in air. In order to carry out these tests, based on the experience gained during the operation of a plate heated on one side, compensated by a reverse heat loss flux counter-heater, a unique double-sided heating sandwich plate was designed and built, consisting of three thin epoxy resin plates reinforced with...
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Rubrene Thin Films with Viably Enhanced Charge Transport Fabricated by Cryo-Matrix-Assisted Laser Evaporation
PublicationAmong organic semiconductors, rubrene (RB; C42H28) is of rapidly growing interest for the development of organic and hybrid electronics due to exceptionally long spin diffusion length and carrier mobility up to 20 cm2V−1s−1 in single crystals. However, the fabrication of RB thin films resembling properties of the bulk remains challenging, mainly because of the RB molecule’s twisted conformation. This hinders the formation of orthorhombic...
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Prediction of flow boiling heat transfer coefficient for carbon dioxide in minichannels and conventional channels
PublicationIn the paper presented are the results of calculations using authors own model to predict heat transfer coefficient during flow boiling of carbon dioxide. The experimental data from various resea rches were collected. Calculations were conducted for a full range of quality variation and a wide range of mass velocity. The aim of the study was to test the sensitivity of the in-house model. The results show the importance of taking into...
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Influence of metallic porous microlayer on pressure drop and heat transfer of stainless steel plate heat exchanger
PublicationThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. On the heat transfer surface of heat exchanger the metallic porous layer was created. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one – the identical heat exchanger but with the modified...
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Experimental Investigation of Free Convection Heat Transfer from Horizontal Cylinder to Nanofluids
PublicationThe results of free convection heat transfer investigation from a horizontal, uniformly heated tube immersed in a nanofluid are presented. Experiments were performed with five base fluids, i.e., ethylene glycol (EG), distilled water (W) and the mixtures of EG and water with the ratios of 60/40, 50/50, 40/60 by volume, so the Rayleigh (Ra) number range was 3 104 Ra 1.3 106 and the Prandtl (Pr) number varied from 4.4 to 176....
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On determining defects identity in carbon nanotubes using charge probes
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Induction heating laboratory stand for estimating thermal properties of a charge
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Charge Loss in Gas-Phase Multiply Negatively Charged Oligonucleotides
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Doping-Induced Immobile Charge Carriers in Polyazomethine: A Spectroscopic Study
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Charge Distribution and Hyperfine Interactions in GdBa2Cu3O7 from First Principles
PublicationW rozdziale przedstawiono wyniki obliczeń "z zasad pierwszych" (''ab initio'') struktury elektronowej, rozkładu ładunku i struktury nadsubtelnej, w szczególności gradientu pola elektrycznego (EFG) i składnika kontaktowego pola nadsubtelnego (HFF), nadprzewodnika wysokotemperaturowego o wzorze GdBa2Cu3O7 (Gd123). Do obliczeń wykorzystano metodę FP-LAPW (full-potential linearized augmented plane wave). Efekty związane z oddziaływaniami...
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Magnetic hyperfine modulation of charge photogeneration in solid films of Alq3.
PublicationZewnętrzne pole magnetyczne (B=100mT) zwiększa fotoprzewodnictwo w hydro-sychinolinowym kompleksie aluminium (Alq3) o 6%. W silniejszych polach magnetycznych (B>100mT) wielkość efektu osiąga stałą wartość. Zaobserwowane wyniki doświadczalne wyjaśniono biorąc pod uwagę magnetyczno-polową modulację oddziaływań nadsubtelnych singletowych i trypletowych par elektron-dziurawy tworzonych w procesie fotogeneracji ładunku.
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A new method for determination of flow boiling heat transfer coefficient in conventional diameter channels and minichannels
PublicationW pracy przedstawiono rozważania związane z modelowaniem wrzenia w przepływie w kanałach o średnicach konwencjonalnych, małych i minikanałach. Przedstawiono przegląd podejść do modelowania wymiany ciepła i w tym świetle przedstawiono oryginalne podejście autora. W przeciwieństwie do innych podejść metoda autora ma zastosowanie zarówno do kanałów o średnicach konwencjonalnych i minikanałach. Przedstawiono zadowalające porównania...
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Influence of metallic porous microlayer on pressure drop and heat transfer of stainless steel plate heat exchanger
PublicationThe experimental analysis of passive heat transfer intensification in the case of plate heat exchanger has been carried out. The metallic porous layer was created on the heat transfer surface of analyzed unit. The experiment was accomplished in two stages. In the first stage the commercial stainless steel gasketed plate heat exchanger was investigated, while in the second one – the identical heat exchanger but with the modified...
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A semi-empirical model for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the present study the attention was focused on the influence of reduced pressure on the predictions of heat transfer during flow boiling at the extensive range of pressures. The results of calculations were to test the sensitivity of the in-house flow boiling model with respect to the selection of the appropriate two-phase flow multiplier, which is one of the distinctive elements of that model. For this purpose a few two-phase...
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Promising Nanoparticle-Based Heat Transfer Fluids—Environmental and Techno-Economic Analysis Compared to Conventional Fluids
PublicationProviding optimal operating conditions is one of the major challenges for effective heating or cooling systems. Moreover, proper adjustment of the heat transfer fluid is also important from the viewpoint of the correct operation, maintenance, and cost efficiency of these systems. Therefore, in this paper, a detailed review of recent work on the subject of conventional and novel heat transfer fluid applications is presented. Particular...
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Modified Inductive Multi-Coil Wireless Power Transfer Approach Based On Z-Source Network
PublicationThis article presents a non-conventional approach to a multi-coil wireless power transfer system based on a Z-source network. The novelty of the approach lies in the use of a Z-source as a voltage source for energy transmission through the wireless power transfer coils. The main advantage is in a reduced number of semiconductors. This paper provides the design approach, simulation and experimental study. Feasibility and possible...
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Cascading transitions toward unconventional charge density wave states in the quasi-two-dimensional monophosphate tungsten bronze P4W16O56
PublicationSingle crystals of the m = 8 member of the low-dimensional monophosphate tungsten bronzes (PO2)4(WO3)2m family were grown by chemical vapour transport technique and the high crystalline quality obtained allowed a reinvestigation of the physical and structural properties. Resistivity measurements revealed three anomalies at TC1 = 258 K, TC2 = 245 K and TC3 = 140 K, never observed until now. Parallel X-ray diffraction investigations...
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Heat transfer intensification by jet impingement – numerical analysis using RANS approach
PublicationJet impingement is a method of the heat transfer enhancement applied in the engineering systems. The idea is to generate fast-flow fluid jet which impinge on the heated (or cooled) surface, causing significantly higher heat transfer rate. Although some flat surface jet impingement cases are described in the literature, the validated data is still limited. The reason is coming from the fact, that these flows are hydrodynamically...
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Numerical analysis of permeability and Darcy effect in heat transfer of pyramid-shaped structure
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Kinetics of the Organic Compounds and Ammonium Nitrogen Electrochemical Oxidation in Landfill Leachates at Boron-Doped Diamond Anodes
PublicationElectrochemical oxidation (EO) of organic compounds and ammonium in the complex matrix of landfill leachates (LLs) was investigated using three different boron-doped diamond electrodes produced on silicon substrate (BDD/Si)(levels of boron doping [B]/[C] = 500, 10,000, and 15,000 ppm—0.5 k; 10 k, and 15 k, respectively) during 8-h tests. The LLs were collected from an old landfill in the Pomerania region (Northern Poland) and were...
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Exploring multi-step glucose oxidation kinetics at GOx-functionalized nanotextured gold surfaces with differential impedimetric technique
PublicationFor a few past years, we can observe the enormous growth of investigations related to ultrasensitive electrochemical sensors capable of reliable determination of important body parameters and analytes. Utilized procedures rely on standard electrochemical methods, demanding electrode polarization, and information about the initial characteristics of the working electrode. More and more complex electrode materials are characterized...
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Experimental study of boiling heat transfer in the stagnation point of water microjet
PublicationIn the paper presented is a comparison of computational model with experimental data. Numerical model of liquid film with phase change in the stagnation zone due to impingement of the microjet is more widely presented in authors previous work. The radius on which theevaporation process is taking place can be determined from the energy balance on the element of the plate. That radius has also been confirmed experimentally in the...
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Influence of nanoparticle concentration on convective heat transfer of water-Al2O3 nanofluids inside horizontal tubes
PublicationNanofluids came to be seen as a new generation of coolants, especially in single-phase systems. Conducted experiments indicate that the increase in thermal conductivity is not the only reason for the intensification of heat transfer when using nanofluids. Preliminary results of the experimental investigation of the forced convection heat transfer of water-Al2O3 nanofluids inside stainless steel tube with 8 mm internal diameter...
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Modelling study of flow boiling heat transfer of perspective fluids for refrigeration technology
PublicationThere is a gap of knowledge on flow boiling at high saturation temperatures and higher values of reduced pressure. Thus far, the in-house developed semi-empirical model for flow boiling and flow condensation showed a satisfactory accuracy for calculations for various refrigeration fluids for a wide scope of reduced pressures. This study presents results of calculations of heat transfer coefficient of perspective refrigeration fluids,...
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Study of the Kinetics of Ammonia Synthesis and Decomposition on Iron and Cobalt Catalysts
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Kinetics studies of recrystallization process of metallic catalysts for ammonia synthesis
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Photoluminescence Kinetics of YAG Crystals Activated with Ce, and Ce and Mg
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Analysis of TL and OSL kinetics in lithium magnesium phosphate crystals
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Kinetics and mechanism of the dehydrohalogenation of Ar2CHCX3 and Ar2CHCHX2 by strong N-bases
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Kinetics of photochromic reactions in a 10-membered dibenzoazo crown ether
PublicationPrzedstawiono rezultaty pomiarów kinetyki fotochromowych reakcji dla jednego z serii eterów koronowych zawierających fragment azobenzenowy. Badano 10-członową dibenzoazokoronę, która ulega odwracalnej foto i termicznej izomeryzacji, podobnie jak macierzysty azobenzen. Eksperymenty były prowadzone w matrycy pMMA. Reakcja izomeryzacji monitorowana była spektrofotometrycznie. Czynnik przedwykładniczy dla termicznej izomeryzacji cis-trans...
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Transparent nanocomposite coatings based on epoxy and layered double hydroxide: Nonisothermal cure kinetics and viscoelastic behavior assessments
PublicationLayered double hydroxide (LDH) has a particular place in clay family because of its flame retardant action. The nanoplatelet-like structure of LDH makes possible development of polymer composites with cationic or anionic nature structures in which macromolecules are positioned in between nanoplatelet galleries. In this work, neat epoxy and its transparent nanocomposite coatings with sodium dodecylbenzene sulfonate (SDBS)-modified...
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Numerical study of turbulent flow and heat transfer of nanofluids in pipes
PublicationIn this work, Nusselt number and friction factor are calculated numerically for turbulent pipe flow (6 000 < Re < 12 000) with constant heat flux boundary condition using nanofluids. The nanofluid is modelled with the single-phase approach and the simulation results are compared with experimental data of Vajjha et al. [1]. Ethylene glycol and water, 60:40 EG/W mass ratio, as base fluid and SiO2 nanoparticles are used as nanofluid...
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How Chain Transfer Leads to a Uniform Polymer Particle Morphology and Prevents Reactor Fouling
PublicationABSTRACT: The effect of adding diethyl zinc as a chain transfer agent during the polymerization of propylene in heptane performed at 80 °C was studied. Although it was expected that the chain transfer would stop after precipitation of the polymer, the polymer molecular weight continued to increase throughout the whole of the polymerization. The presence of diethyl zinc had an additional effect that the polymerizations were devoid...