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Photovoltaic phenomena in devices with perfluorozincphthalocyanine layer
PublicationThe course of photovoltaic phenomenon in organic photovoltaic cells utilizing thin layers of perfluorozincphthalocyanine was studied in few single and planar bilayer configurations. Mechanisms of photogeneration and recombination of free charge carriers were determined and active interfaces were localized. In case of single layer cells these interfaces were located at the front electrode/F16ZnPc junctions, whereas photogeneration...
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Propagation of Acoustic Disturbances in Shallow Sea
PublicationPropagation of acoustic waves in shallow sea differs fundamentally from the same phenomenon occurring in deep sea in view of non-negligible distance from the sea bottom in the first case, where presence of two regions limiting the water layer results in the acoustic pressure distribution induced by a harmonic source has an interferential nature as a result of multi-path propagation of the acoustic signal. These interferential properties...
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The structure of demand and its economic consequences for urban transport
PublicationThe structure of demand for urban transport services, determined by the share of passengers entitled to free and reduced fares, is an important factor influencing its economic condition. The aim of this article is to present the results of research into the structure of demand for urban transport as well as its economic consequences. The article begins by considering the nature of the determinants and consequences of the public...
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Dynamics of Antimicrobial Peptide Encapsulation in Carbon Nanotubes: The Role of Hydroxylation
PublicationIntroduction: Carbon nanotubes (CNTs) have been widely employed as biomolecule carriers, but there is a need for further functionalization to broaden their therapeutic application in aqueous environments. A few reports have unraveled biomolecule–CNT interactions as a measure of response of the nanocarrier to drug-encapsulation dynamics. Methods: Herein, the dynamics of encapsulation of the antimicrobial peptide HA-FD-13 (accession...
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A Circular Waveguide Dual-Mode Filter With Improved Out-of-Band Performance for Satellite Communication Systems
PublicationThis letter presents a novel design for a 3-D-printed circular waveguide dual-mode (CWDM) filter with a modified cavity shape. The modification leads to a wide spurious-free stopband, which is highly desirable for channel separation in waveguide contiguous output multiplexers (OMUXs) in satellite communication systems. The new resonant cavity design is a result of applying shape deformation to a basic circular cavity in order to...
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A current-controlled FET
PublicationA novel semiconductor device, viz., Horizontally-Split-Drain Current-Controlled Field-Effect Transistor (HSDCCFET) with two control electrodes is proposed in this works. For the sake of brevity, the device can be called a CCFET. Operating principle of the proposed transistor is based on one of the galvanomagnetic phenomena, the Biot-Savart-Laplace law and a Gradual Channel Detachment Effect (GCDE). The transistor is dedicated...
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Thermal visualization of Ostwald-de Waele liquid in wavy trapezoidal cavity: Effect of undulation and amplitude
PublicationThe present study is concerned with the numerical simulations of Ostwald-de Waele fluid flow in a wavy trapezoidal cavity in the presence of a heated cylinder situated at the center of the cavity. The work consists in characterizing the mixed convection as a function of the intensity of heat flow. The flow behaviour and temperature distribution in a cavity are the main focus of this study. The lower wall of the cavity is fixed...
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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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Photovoltaic properties of cadmium selenide–titanyl phthalocyanine planar heterojunction devices
PublicationPhotovoltaic phenomenon taking place in cadmium selenide (CdSe)/titanyl phthalocyanine (TiOPc) planar heterojunction devices is described. Mechanisms of free charge carrier generation and their recombination in the dark and under illumination are analyzed, chosen photovoltaic parameters are presented.
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Dissection of σE‐dependent cell lysis in Escherichia coli: roles of RpoE regulators RseA, RseB and periplasmic folding catalyst PpiD
PublicationTo understand the mechanism of sigma(E)-dependent cell lysis, we examined the consequences of deletion derivatives of rpoE regulators rseA, rseB and rseC on sigma(E) transcription, on levels of free versus membrane-bound sigma(E) and on OMP-biogenesis limiting factor(s) that could impact cell lysis. RT-PCR showed that individual nonpolar DeltarseA and DeltarseB increased the rpoE expression to varying extents, with pronounced induction...
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Improved cytotoxicity and preserved level of cell death induced in colon cancer cells by doxorubicin after its conjugation with iron-oxide magnetic nanoparticles
PublicationA promising strategy for overcoming the problem of limited efficacy in antitumor drug delivery and in drug release is the use of a nanoparticle-conjugated drug. Doxorubicin (Dox) anticancer chemotherapeutics has been widely studied in this respect, because of severe cardiotoxic side effects. Here, we investigated the cytotoxic effects, the uptake process, the changes in cell cycle progression and the cell death processes in the...
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Experimental dynamic study on a timber-frame house using shaking table
PublicationThe aim of this paper is to show the results of the shaking table experimental study concerning the behaviour of the model of the timber-frame house under earthquake excitation and impact loading. In order to determine the basic dynamic properties of the undamaged structure, the free vibration and the sweep-sine tests were first conducted. Then, the model was excited using the time history record of the El Centro earthquake of...
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System information propagation for composite structures
PublicationWe study in details decoherence process of a spin register, coupled to a spin environment. We use recently developed methods of information transfer study in open quantum systems to analyze information flow between the register and its environment. We show that there are regimes when not only the register decoheres effectively to a classical bit string, but this bit string is redundantly encoded in the environment, making it available...
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Estimation and Prediction of Vertical Deformations of Random Surfaces, Applying the Total Least Squares Collocation Method
PublicationThis paper proposes a method for determining the vertical deformations treated as random fields. It is assumed that the monitored surfaces are subject not only to deterministic deformations, but also to random fluctuations. Furthermore, the existence of random noise coming from surface’s vibrations is also assumed. Such noise disturbs the deformation’s functional models. Surface monitoring with the use of the geodetic levelling...
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How Important Is Research on Pollution Levels in Antarctica? Historical Approach, Difficulties and Current Trends
PublicationDespite the fact that Antarctica is a continent notably free from large negative impact of human activities, literature data can be the basis for concluding that this is not an area free from anthropogenic pollutants. Pollutants, which are identified in various elements of the environment of Antarctica, are mostly connected with long-range atmospheric transport (LRAT) and deposition in this area. The study presents: a historical...
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Praca bibliotekarza w erze cyfrowej: 20 darmowych programów i aplikacji do wykorzystania w bibliotece
PublicationArtykuł prezentuje 20 darmowych programów komputerowych, wykorzystywanych w Bibliotece Głównej Gdańskiego Uniwersytetu Medycznego. Przedstawione aplikacje mogą wzbogacić warsztat pracy bibliotekarzy, którzy zajmują się: tworzeniem szkoleń, edycją bibliotecznych stron internetowych oraz komunikacją z użytkownikami.
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MANAGING LEARNING PROCESS WITH E-LEARNING TOOL
PublicationThis article presents one possibility to employ Moodle, the free e-Leaning platform, to organize learning understood as a process. Behavioral approach and application to massive courses are assumed. A case study is presented, where the introduction of Moodle resulted in better student performance in homework
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Verification of algorithms determining wave loads on support structure of wind turbine
PublicationThe offshore wind turbines require determination of wave loads on their support structure. This structure is fixed and, therefore, this problem is reduced to solving only the diffraction problem, which is determined by Laplace equation and conditions on the following boundaries: on the support structure, on the sea free surface and on its bottom, and at infinity on free surface. The linear problem was applied to determine the wave...
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publication: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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SYNTHESIS AND PROPERTIES OF OLIGOMERS WITH HYDROXY END-GROUPS
PublicationMethods of oligomers (polymers) with hydroxy end-groups obtaining are examined. The synthesis of hydroxy-containing oligomers based on epoxy resins is of special attention. The molecules of mentioned oligomers apart from free primary and secondary hydroxy groups contain epoxy, peroxy, carboxy or acrylic groups.
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3-Monochloropropane-1,2-diol in Infant Foods and Human Breast Milk: Determination by GC-MS
Publication3-Monochloropropane-1,2-diol is one of the food borne contaminants called chloropropanols. Over the last decade plenty of analytical methods was developed in order to determine 3-monochloropropane-1,2-diol in its free and bound form in various foodstuffs with the use of GC-FID, GC-ECD, LC-TOFMS and finally GC-MS, which is now widely used in laboratories. The aim of this research was the determination of 3-monochloropropane--1,2-diol...
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From grey to green
PublicationThe article presents conceptual project made by students during Urban European Summer School “City on water” in Bremen 2015. The area of study was Hemelingen, Aller-Harbour, Bremen, Germany. The aim was to make a design of regeneration of the area. Students were free in choosing methods and ideas for their project.
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Geokompozyty drenażowe w odwodnieniach drogowych i kolejowych
PublicationZagadnienie zagospodarowania wód opadowych i gruntowych w rejonie konstrukcji drogowych i kolejowych stanowi istotny element bezpiecznej i efektywnej eksploatacji tych obiektów. Odpowiednie wykorzystanie geokompozytów drenażowych zapewnia bezproblemową pracę konstrukcji oraz właściwą ochronę przed uszkodzeniami wynikającymi z niekontrolowanego oddziaływania wody.
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Comparison of developed gaze point estimation methods
PublicationThis paper presents the software part of an inexpensive hands-free eye tracking system. The system works using infrared illumination like most of the available eye trackers. Two methods allowing estimation the gaze point on computer screen are compared. Research on effectiveness of these methods is discussed and the better one is indicated.
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Mechanochemical Energy Transduction during the Main Rotary Step in the Synthesis Cycle of F1-ATPase
PublicationF1-ATPase is a highly efficient molecular motor that can synthesize ATP driven by a mechanical torque. Its ability to function reversibly in either direction requires tight mechanochemical coupling between the catalytic domain and the rotating central shaft, as well as temporal control of substrate binding and product release. Despite great efforts and significant progress, the molecular details of this synchronized and fine-tuned...
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How to make membrane distillation greener? A review on environmentally friendly and sustainable aspects
PublicationThere is an urgent need for the development of new water resources in order to solve the problem of the world’s growing demand for clean water. Membrane distillation (MD) is a promising alternative to conventional seawater desalination. Although MD itself is often defined as sustainable desalination technology, there are many aspects within the membrane manufacture and process operation that make it far from being green. For instance,...
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A Nyquist filter of fractional delay
PublicationIn the paper a novel discrete-time FIR fractonal delay specjal filter is investigated. This is a Nyquist filter which, besides the traditional its attribute (interymbol interference (ISI) free property), has the ability to compensate for subsample transmission delay involved, for example, in multipath propagation channel. The performance of the filter is analysed and illustrated.
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Adapting a General Tool to Monitoring Multi-Agent Systems Through Virtual Host Layer Extenstion
PublicationNagios is a free software for IT infrastructure monitoring. Out-of-the-box it is not suited for monitoring multi-agent systems, because agents may dynamically join and leave the system or change roles. But Nagios' flexible configuration makes extensions possible. This paper presents and verifies Nagios configuration and extensions for monitoring multi-agent systems.
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Mury oporowe z gruntu zbrojonego z przekładkami z keramzytu
PublicationW czerwcu 2019 r. nastąpiło otwarcie nowo budowanego wiaduktu na ulicy Drwęckiej w Ostródzie, który zastąpił jeden z trzech przejazdów kolejowo-drogowych znajdujących się w centrum miasta. Zakończenie budowy bezkolizyjnego przejazdu nad torami kolejowymi pozwoliło na bezpieczne oraz szybkie połączenie północnej i południowej części Ostródy. Zastosowanie materacy z keramzytu w konstrukcji z gruntu zbrojonego.
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Influence of pyrolysis atmosphere on the lithium storage properties of carbon-rich polymer derived SiOC ceramic anodes
PublicationPolymer derived carbon-rich SiOC ceramics are prepared from polysiloxane precursors through a pyrolysis process at 1000 °C using pure argon and argon/hydrogen mixture as pyrolysis atmosphere. The precursor is synthesized from a linear (Si–H)-containing polysiloxane cross-linked with divinylbenzene using hydrosilylation reaction in the presence of a platinum catalyst. Pyrolysis in Ar/H2 mixtures, compared to the treatment under...
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A dynamic vehicle-bridge model based on the modal identification results of an existing EN57 train and bridge spans with non-ballasted tracks
PublicationThis paper addresses the methodology of the bridge-vehicle dynamic model definition based on the free response measurements of an existing train and existing bridge spans. In the case of the railway vehicle, the methodology uses the impulse excitations of a single car by means of the wedge method. In the case of the bridge spans, free responses are collected after the passages of trains. The global modal parameters (frequencies...
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Synthesis and antimicrobial activity of amino acid and peptide derivatives of mycophenolic acid
PublicationThe series of 16 novel amino acid and peptide mycophenolic acid (MPA) derivatives was obtained as potential antibacterial agents. Coupling of MPA with respective amines was optimized with condensing reagents such as EDCI/DMAP and T3P/TEA. Amino acid analogs were received both as methyl esters and also with the free carboxylic group. The biological activity of the products was tested on five references bacterial strains: Klebsiella...
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Study on applicability of two modal identification techniques in irrelevant cases
PublicationStudy on applicability of two modal identification techniques in irrelevant cases is made in this paper. The following techniques are considered: Peak Picking based on correlation analysis (PP-CA), dedicated for ambient vibrations and Eigensystem Realization Algorithm (ERA), formulated for free decay vibrations investigation. Irrelevant cases are found when analyzed signals are different than recommended to a given technique. The...
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Synthesis, anticandidal activity of N3-(4-methoxyfumaroyl)-(S)-2,3-diaminopropanoic amide derivatives – Novel inhibitors of glucosamine-6-phosphate synthase
PublicationNovel FMDP amiders 4-6 have been synthesized and tested against Candida strains. The anticandidal activity has been confined only to Candida albicans. Anticandidal activity of the tested amides has correlated with their inhibitory activity of glucosamine-6-phosphate synthase in cell free extract from Candida albicans.
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Preparation, composition and properties of fish silage produced with post-coagulation sludge
PublicationPost-coagulation sludge was added to fish fydrolyzates (silage). Silage was prepared using whole sprats. Technology of the process has been modified and sulphuric acid was replaced with phosphoric acid. The objective was to evaleuate the quality of produced silage during storage, particulary the changes of peroxide value and amount of free acids in silage fat.
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RP-HPLC WITH DETECTION BY MEANS OF ESI-MS AND UV FOR IDENTIFICATION OF CHROMATOGRAPHIC PEAKS OF SOME HYDROXY DERIVATIVES OF EPOXY RESIN
PublicationThe composition of products synthesized on the basis of ED-24 epoxy resin has been studied using a reversed phase high-performance liquid chromatography followed by an electrospray ionization mass spectrometry (RP-HPLC/ESI-MS). The synthesized products contain free hydroxy groups and such groups, as epoxy, peroxy, carboxy or acrylate.
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La Città Libera di Danzica: compromesso ragionevole o scommessa impossibile?
PublicationThe article outlines the main economic ptoblems connected with the birth of the Free city of Danzig. In particular, it studies the complex relationships between the city, the Polish government, the League of Nations, and the Allies about the use of the port of Danzig and the increasing competition with the port of Gdynia, built by the Polish government with support of the French one and some french private companies.
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CRVG - a new model for wireless networks topology generation
PublicationThis paper presents a new model of wireless network topology generator. Its main advantage is the possibility of relatively sparse networks generation. Because no iteration is needed, the model can be used for massive generation of networks for testing. The topological properties of produced graphs place them in the class of scale free networks, resembling real ones.
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The vortex flow caused by sound in a bubbly liquid
PublicationGeneration of vorticity in the field of intense sound in a bubbly liquid in the free half-space is considered. The reasons for generation of vorticity are nonlinearity, diffraction, and dispersion. Acoustic streaming differs from that in a Newtonian fluid. Under some conditions, the vortex flow changes its direction. Conclusions concern streaming induced by a harmonic or an impulse Gaussian beam.
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Design of new cholinesterase inhibitors based on phosphorus analogs of tacrine as potential anti-Alzheimer’s disease agents
PublicationBased on the analysis of the determined free binding energy (using the AutoDock Vina 1.1.2 docking program), the most potent cholinesterase inhibitors were selected. Moreover, studies of 3D visualization of the results of molecular modeling led to the identification of potential sites for the interaction of new potential inhibitors with amino acid residues building active sites of investigated cholinesterases.
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A novel hierarchically-porous diamondized polyacrylonitrile sponge-like electrodes for acetaminophen electrochemical detection
PublicationA novel composite electrode material consisting of tangled fibrous polyacrylonitrile-based hierarchically-struc- tured nanocomposites has been produced by wet-spinning, carbonized and decorated with a carbon nano- architecture by microwave plasma-enhanced chemical vapor deposition and investigated as a metal-free electrode for the enhanced electrochemical detection of acetaminophen. Surprisingly, the hierarchical fiber ar- chitecture...
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Development of the New Polish Method for Capacity Analysis of Motorways and Expressways
PublicationThe paper presents development of the new Polish method for performing capacity analysis of basic segments of dual carriageway roads (motorways and expressways). The method is based on field traffic surveys conducted at 30 motorway and expressway sites (class A and S roads) in Poland. Traffic flows, composition and travel times were observed in 15-min intervals at each site using ANPR filming method. These data were used to calibrate...
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Induction motor bearings diagnostic indicators based on MCSA and normalized triple covariance
PublicationInduction motors are one of the most widely used electrical machines. Statistics of bearing failures of induction motors indicate, that they constitute more than 40% of induction motor damage. Therefore, bearing diagnosis is so important for trouble-free work of induction motors. The most common methods of bearing diagnosis are based on vibration signal analysis. The main disadvantage of those methods is the need for physical access...
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Theoretical Encapsulation of Fluorouracil (5-FU) Anti-Cancer Chemotherapy Drug into Carbon Nanotubes (CNT) and Boron Nitride Nanotubes (BNNT)
PublicationIntroduction: Chemotherapy with anti-cancer drugs is considered the most common approach for killing cancer cells in the human body. However, some barriers such as toxicity and side effects would limit its usage. In this regard, nano-based drug delivery systems have emerged as cost-effective and efficient for sustained and targeted drug delivery. Nanotubes such as carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) are promising...
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Molecular Recognition in Complexes of TRF Proteins with Telomeric DNA
PublicationTelomeres are specialized nucleoprotein assemblies that protect the ends of linear chromosomes. In humans and many other species, telomeres consist of tandem TTAGGG repeats bound by a protein complex known as shelterin that remodels telomeric DNA into a protective loop structure and regulates telomere homeostasis. Shelterin recognizes telomeric repeats through its two major components known as Telomere Repeat-Binding Factors, TRF1...
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Chemically Selective Alternatives to Photoferroelectrics for Polarization-Enhanced Photocatalysis: The Untapped Potential of Hybrid Inorganic Nanotubes
PublicationLinear-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.
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Time-domine Dipole Fields in acoustic and Elektromagnetics
PublicationThe ultrawideband (UWB) radio technique presents a challenge not just for technology. The UWB carrier-free pulses act at a close distance, their electromagnetic fields being very different from classic monochromatic plane wave. The author proposes to adapt a time-domian approach to analysis of broadband spherical fields, both acoustic and electromagnetic, in fundamental cases of quasi-point physical sources.
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Visualization of Spatial Issues in Adobe Acrobat 3D PDF
PublicationThe ability to capture and embed model information in a 3D PDF file and subsequently share it for free is highly needed in the education of descriptive geometry. The described technology and in particular inserting 3D models into the other files can improve the existing teaching materials. The strongest point of 3D PDF technology is that the model can be visualized and manipulated in multiple ways by viewers which enhance the...
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Hyaluronic acid/tannic acid films for wound healing application
PublicationIn this study, thin films based on hyaluronic acid (HA) with tannic acid (TA) were investigated in three different weight ratios (80HA/20TA, 50HA/50TA, 20HA/80TA) for their application as materials for wound healing. Surface free energy, as well as their roughness, mechanical properties, water vapor permeability rate, and antioxidant activity were determined. Moreover, their compatibility with blood and osteoblast cells was investigated....
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Structural and electronic properties of diamond-composed heterostructures
PublicationDiamond is a promising material for 21st century electronics due to its high thermal and electronic conductivity, biocompatibility, chemical stability, high wear resistance, and possibility of doping. However, the semiconductor properties of diamond, especially free-standing films, have not been fully explored. Nor have their integration with polymers and fragile materials and their applications as electronic components. In this...