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  • Performance of Noise Map Service Working in Cloud Computing Environment
    • Karolina Marciniuk
    • Maciej Szczodrak
    • Bożena Kostek
    2016 Pełny tekst Archives of Acoustics

    In the paper a noise map service designated for the user interested in environmental noise subject is presented. It is based on cloud computing. Noise prediction algorithm and source model, developed for creating acoustic maps, are working in cloud computing environment. In the study issues related to noise modeling of sound propagation in urban spaces are discussed with a special focus on road noise. Examples of results obtained employing a web application created for that purpose are shown. Also, a comparison between the web-based results and those obtained from the commercial software simulations for two road noise prediction models is carried out. The user-interface design and ergonomics of the web application developed, as well its computing efficiency, are tested and analyzed. In the paper a flowchart simulating the operation of the noise webbased service is presented showing that the created application is easy to use even for people with little experience in computers.

  • Performance of the flat plate solar collector operated with water-Al2O3 nanofluid
    • Janusz Cieśliński
    • Bartosz Dawidowicz
    • Aleksandra Popakul
    2016 Applied Mechanics and Materials

    The paper discusses the effect of application of water-Al2O3 nanofluid, as a working fluid, on the efficiency of a flat plate solar collector. The mass concentration of nanoparticles was 0.1%, 0.2% and 0.4%. The tests were conducted for two values of radiation of about 1050 W/m2 and 400 W/m2, and volume flow rates of 60 l/h, 120 l/h and 170 l/h. The efficiency was calculated according to recommendations of the Polish Standard. The results show that the application of nanofluids instead of pure water resulted in higher efficiency of the tested flat plate solar collector for given range of thermal radiation. Independent of the volume flow rate of the nanofluid, the maximum efficiency was recorded for nanoparticle concentration equal to 0.2%.

  • PERFORMANCE OF THE PVT SOLAR COLLECTOR OPERATED WITH WATER –AL2O3 NANOFLUID
    • Janusz Cieśliński
    • Bartosz Dawidowicz
    • Jan Krzyżak
    2016 Polska Energetyka Słoneczna

    An experimental investigation of the hybrid module photovoltaic panel -solar collector (PVT) cooled by water-Al2O3 nanofluids has been conducted. The weight fractions of the nanoparticles were 1% and 3%. Thermal efficiency, power efficiency and overall efficiency have been determined for artificial source of light and sunlight. No noticeable effect of the nanoparticle concentration on the overall efficiency of the PVT module has been recorded while using water-Al2O3 nanofluids as a cooling medium. Moreover the reduction of the electrical power generated with increasing temperature of the module has been recorded.

  • Performance of the PVT solar collector operated with water-Al2O3 nanofluid
    • Janusz Cieśliński
    • Bartosz Dawidowicz
    • Jan Krzyżak
    2016

    An experimental investigation of the hybrid module photovoltaic panel -solar collector (PVT) cooled by water-Al2O3 nanofluids has been conducted. The weight fractions of the nanoparticles were 1% and 3%. Thermal efficiency, power efficiency and overall efficiency have been determined for artificial source of light and sunlight. No noticeable effect of the nanoparticle concentration on the overall efficiency of the PVT module has been recorded while using water-Al2O3 nanofluids as a cooling medium. Moreover the reduction of the electrical power generated with increasing temperature of the module has been recorded.

  • Performance of zinc-rich coatings evaluated using AFM-based electrical properties imaging
    • Michał Szociński
    • Kazimierz Darowicki
    2016 PROGRESS IN ORGANIC COATINGS

    The paper presents the results of investigation of polyvinyl zinc-rich coating exposed to 97% relativehumidity atmosphere for 40 days. Condition of the coating and evolution of its protective properties weredetermined with the novel AFM-based approach capable of providing surface profiles, local dc currentmaps as well as local impedance spectra. The proposed technique allowed insight into the local changesof coating topography and electrical properties accompanying a transition from purely electrochemicalto barrier mechanism of protection. The AFM-based approach made it possible to assess what fraction ofthe coating surface was covered with non-conductive zinc corrosion products at given stage of exposureand what the advance of transition between particular protection mechanisms was. The results providedadditional, complimentary information as compared to the global averaging techniques such as classicalelectrochemical impedance spectroscopy and electrochemical potential measurements.

  • Perfusion computed tomography: 4 cmversus8 cm coverage size in subjects with chronic carotid artery stenosis
    • Arkadiusz Szarmach
    • Grzegorz Halena
    • Mariusz Franciszek Kaszubowski
    • Maciej Piskunowicz
    • Edyta Szurowska
    • Andrzej Frydrychowski
    • Pawel Winklewski
    2016 BRITISH JOURNAL OF RADIOLOGY

    OBJECTIVE: The impact of coverage size on global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) and time to peak (TTP) parameters has not been investigated in patients with chronic carotid artery stenosis. METHODS: 63 patients with stenosis of >70% within a single internal carotid artery and neurological symptoms were randomly assigned to two well-matched groups. Differences in CT perfusion scan over a 4 cm or 8 cm range of the brain were compared between the two groups. RESULTS: The CBF and CBV values were higher in the 4 cm coverage size than in the 8 cm coverage size (by 14.7 and 10.7% on the ipsilateral side and 17.2 and 7.8% on the contralateral side, respectively; all p < 0.001). The MTT value was higher in the 4 cm coverage size than in the 8 cm coverage size on the ipsilateral side (9.6%; p < 0.001). There was no difference between MTT values in the contralateral size. There were no differences between TTP values on the ipsilateral and contralateral sides. The relative indices rMTT and rTTP were higher in the 4 cm coverage size than in the 8 cm coverage size (8.2%, p < 0.001, and 1.1%, p < 0.005, respectively). CONCLUSION: Absolute CBF and CBV values and relative rMTT and rTTP indices in patients with low CBF and low CBV are highly dependent on coverage size. We recommend using a 4 cm coverage size to assess global cerebral perfusion parameters owing to better accuracy and quicker post-processing. ADVANCES IN KNOWLEDGE: To the best of our knowledge, this is the first article to compare the influence of 4 cm vs 8 cm coverage size on cerebral perfusion parameters such as CBF, CBV, MTT and TTP in subjects with chronic carotid artery stenosis.

  • Periodic points of latitudinal maps of the $m$-dimensional sphere
    • Grzegorz Graff
    • Michał Misiurewicz
    • Piotr Nowak-Przygodzki
    2016 DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS

    Let f be a smooth self-map of the m-dimensional sphere Sm. Under the assumption that f preserves latitudinal foliations with the fibres S1, we estimate from below the number of fixed points of the iterates of f. The paper generalizes the results obtained by Pugh and Shub and by Misiurewicz.

  • Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics
    • Arkadiusz Żak
    • Marek Krawczuk
    • Magdalena Palacz
    2016 Pełny tekst MATHEMATICAL PROBLEMS IN ENGINEERING

    Finite element discrete models of various engineering 1D structures may be considered as structures of certain periodic characteristics. The source of this periodicity comes from the discontinuity of stress/strain field between the elements. This behaviour remains unnoticeable, when low frequency dynamics of these structures is investigated. At high frequency regimes, however, its influence may be strong enough to dominate calculated structural responses distorting or even falsifying them completely. In this paper, certain computational aspects of structural periodicity of 1D FE discrete models are discussed by the authors. In this discussion, the authors focus their attention on an exemplary problem of 1D rod modelled according to the elementary theory.

  • Peripheral industrial NUTS 3 sub-regions in the European Union – identification and typology
    • Jacek Sołtys
    • Sławomir Dorocki
    2016 Pełny tekst Prace Komisji Geografii Przemysłu Polskiego Towarzystwa Geograficznego

    A common phenomenon of development is the big difference in its levels, especially between metropolitan and non-metropolitan areas. Non-metropolitan areas are also very different. In some of them, industry plays a big role. European Union’s NUTS 3 non-metropolitan low developed sub-regions, whose gross domestic product per capita in 2011 was below 75% of the EU average, were the subject of research. It is based on the data and Principal Component Analysis used for the typology of 319 sub-regions prepared in 2014. The purposes of the research presented were to identify industrial sub-regions among aforementioned sub-regions, to investigate their diversity and to recognize more detailed sub-regions with the most developed industry. There was also a methodological purpose: to verify a concept for taking into account the weight of principal component in grouping sub-regions into types. As many as 53 sub-regions, in which the rate of gross value added in industry (in %) is 3 times bigger than average in the whole set of the sub-regions examined (that is more than 35%) were defined as industrial. Typology for these sub-regions was made by the cluster analysis using hierarchical method and grouping sub-regions into four types. More detailed characteristics of some sub-regions is the last part of this work.

  • Perspektywy nowoczesnej diagnostyki połączeń dźwigarów mostowych z wykorzystaniem fal sprężystych
    • Rafał Kędra
    • Magdalena Rucka
    2016 Materiały Budowlane

    W artykule przedstawiono wyniki analiz doświadczalnych propagacji fal sprężystych w modelu laboratoryjnym połączenia nakładkowego dwuteowego dźwigara blachownicowego. Badano możliwość wykrycia całkowitego poluzowania pojedynczych śrub i grup łączników. Przeanalizowano zmiany jakościowe zarejestrowanych sygnałów, ich wpływ na energię sygnału oraz współczynnik korelacji krzyżowej. Wy kazano możliwość zastosowania fal sprężystych do wykrywania uszkodzenia i jego ewolucji.

  • Perspektywy obsługi miast autobusami elektrycznymi na przykładzie Sopotu
    • Krzysztof Grzelec
    • Dominik Okrój
    2016 Pełny tekst Autobusy. Technika, Eksploatacja, Systemy Transportowe

    W ramach zaostrzających się wymagań dotyczących ochrony środowiska, władze miast poszukują rozwiązań mających na celu ograniczenie emisji zanieczyszczeń. W sektorze transportu, in-nowacyjnym rozwiązaniem umożliwiającym zmniejszenie emisji spalin, jest zastosowanie "czyst-szych" środków transportu miejskiego - elektrobusów. Pojazdy o napędzie elektrycznym stanowią jeden z filarów realizacji polityki zrównoważonej mobilności w miastach i aglomeracjach. Aspekty ekologiczne, ekonomiczne (niskie koszty eksploatacji) i większa elastyczność obsługi w porównaniu z tramwajami i trolejbusami, są najczęściej wymienianymi determinantami wprowadzenia tego nowego rodzaju pojazdów elektrycznych do eksploatacji. Sopot jako miasto uzdrowiskowe jest w szczególnym stopniu predestynowany do obsługi pojazdami elektrycznymi. Jednocześnie funkcjonująca na obszarze tego miasta komunikacja trolejbusowa stwarza określone warunki dla funkcjonowania i rozwoju elektrobusów. Celem niniejszego referatu jest analiza możliwości oraz uwarunkowań wprowadzenia elektrobusów do obsługi miast oraz analiza wariantów obsługi elektrobusami wybranego miasta - Sopotu. Do oceny wariantów wykorzystano analizę DGC, która pokazuje techniczny koszt uzyskania jednostki efektu ekologicznego (zl/km) oraz umożliwia uszeregowanie wariantów obsługi od najtańszego do najdroższego.

  • Perspektywy stabilizacji dochodów producentów rolnych na przykładzie rynku zbóż w Polsce po kryzysie finansowym
    • Piotr Giruć
    2016

    Rynek zbożowy w Polsce nie funkcjonuje wystarczająco sprawnie. W związku z tym nie zapewnia stabilnych dochodów zarówno producentom zbóż jak i rolnikom prowadzącym chów różnych grup zwierząt, a także wielu gałęziom przemysłu, dla których ziarno zbóż jest surowcem. W celu zwiększenia stabilności polskiego rynku zbóż istotne jest stworzenie większych możliwości eksportowania ziarna z Polski. Polska już teraz jest trzecim co do wielkości producentem zbóż w Unii Europejskiej (po Niemczech i Francji) - a nadwyżka w produkcji zboża sięgają kilku milionów ton. Natomiast, jeśli chodzi o infrastrukturę do przechowywania zboża oraz bazę eksportową, to wciąż pozostajemy daleko w tyle za europejską czołówką. W celu poprawy stanu infrastruktury należałoby skupić się na rozbudowie obiektów portowych przeznaczonych do magazynowania i przeładunku zboża oraz umożliwiających szybki załadunek dużych statków. Dotyczy to głównie modernizacji i rozbudowy Terminali Zbożowych w Gdyni i w Gdańsku. W pracy przedstawiono dane statystyczne dotyczące rozwoju rynku zbóż w Polsce i w innych krajach Unii Europejskiej oraz zaprezentowano dysfunkcje ograniczające rozwój rynku zbóż w Polsce, które przyczyniają się do spadku dochodów producentów zbóż.

  • Phage-Directed Synthesis of Photoluminescent Zinc Oxide Nanoparticles under Benign Conditions
    • Kamila Sadowska
    • Joanna Karczewska-Golec
    • Jakub Karczewski
    • Marcin Łoś
    • Andrzej Kłonkowski
    • Grzegorz Węgrzyn
    • Piotr Golec
    2016 BIOCONJUGATE CHEMISTRY

    Biological systems, especially bacteriophages and peptides, are an attractive green alternative to other known methods of nanoparticle synthesis. In this work, for the first time, bacteriophages were employed to synthesize a specific peptide, capable of producing nanoparticles (NPs). Derivatives of M13 bacteriophage exposing a ZnO-binding peptide (TMGA-LGLKWPV) on either pIII or pVIII phage coat protein were constructed and used as a biotemplate. The exposition of the ZnO-binding peptide, synthesized by phages during their propagation in bacteria, on M13 virions provided a groundwork for growing ZnO nanostructures. Depending on the recombinant phage type used (M13-pIII-ZnO or 13-pVIII-ZnO), well separated ZnO NPs or complex 3D structures of ZnO NPs of ca. 20−40 nm were synthesized at room temperature. The synthesized ZnO nanoparticles served as a luminescent material that emitted light near the short wavelength end of the visible region (at ca. 400 nm). The next very low intensity emission band at 530 nm demonstrated that the ZnO material obtained is characterized by a low concentration of surface defects.

  • Phosphoroorganic Metal Complexes in Therapeutics
    • Sebastian Demkowicz
    • Witold Kozak
    • Mateusz Daśko
    • Janusz Rachoń
    2016 MINI-REVIEWS IN MEDICINAL CHEMISTRY

    The present mini-review highlights recent developments on antitumor activity of metal-based therapeutics which have been a subject of researches for the last few decades. In 1965, Rosenberg found that during an electrolysis on platinum electrodes a complex of Pt is generated which inhibited to a great extent a binary fission in Escherichia coli bacteria. This discovery started a new chapter in medicinal chemistry and the interesting properties of cisplatin were soon applied in cancer therapy especially in curing genitourinary tumors. However, various side effects limited its use in medical treatment. Since then a great number of other metal-organic complexes based on platinum, palladium, ruthenium, gold, copper, silver, rhodium, osmium, rhenium, iridium and others have been synthesized. Among them, NAMI-A and KP1019 have recently undergone clinical trials. In this review paper we report a detailed account of metal complexes with phosphorus-based ligands which are of particular interest in therapeutics.

  • Photocatalytic activity of nitrogen doped TiO2 nanotubes prepared by anodic oxidation: The effect of applied voltage, anodization time and amount of nitrogen dopant
    • Paweł Mazierski
    • Michał Nischk
    • Marta Gołkowska
    • Wojciech Lisowski
    • Maria Gazda
    • Michał Jerzy Winiarski
    • Tomasz Klimczuk
    • Adriana Zaleska-Medynska
    2016 APPLIED CATALYSIS B-ENVIRONMENTAL

    Nitrogen doped TiO2 nanotube arrays were prepared by anodizing Ti foils in an organic electrolyte containing specified amounts of urea as nitrogen precursor. The photocatalytic activity of the samples was evaluated by analyzing the degradation kinetics of phenol in water. The influence of tubes’ length, tubes’ surface morphology and amount of nitrogen in the TiO2 lattice on hydroxyl radical formation efficiency, photocatalytic activity and stability in four cycles was investigated. It was found that the photocatalytic activity as well as the charge carrier recombination rate depends on nitrogen concentration and the process parameters. 3.5 m-long nanotubes containing 0.34 at.% of nitrogen seems to be favorable in phenol degradation and OH radicals generation under visible light. Comparison of XPS and photocatalytic activity test results shows decrease in phenol degradation efficiency with increasing amount of carbon contaminants on photocatalysts’ surface.

  • Photoelectron and threshold photoelectron valence spectra of pyridine
    • Małgorzata Śmiałek-Telega
    • Michael MacDonald
    • Sylwia Ptasińska
    • Lucia Zuin
    • Nigel J. Mason
    2016 Pełny tekst EUROPEAN PHYSICAL JOURNAL D

    . The pyridine molecule has been examined by the means of photoelectron and threshold photoelectron spectroscopies. Ionization energies were determined for both outer and inner valence orbitals and new adiabatic values were also resolved. Vibronic structure associated with several states was assigned mainly to be due to C–C stretches and ring bends. Additionally a Rydberg state converging to 7b2 state was ascribed. The data shown here are in a good agreement with previous results and brings some new insights into the electronic structure of this biologically and astrochemically relevant and important molecule.

  • Photoelectron-photoabsorption (PePa) database
    • Małgorzata Śmiałek-Telega
    • Nigel J. Mason
    2016 Pełny tekst EUROPEAN PHYSICAL JOURNAL D

    In this paper a recently launched Photoelectron-Photoabsorption Database is presented. The database was developed in order to gather all the photoelectron and photoabsorption spectra measured by various collaborators over the years as well as to ease the access to the data to the potential users. In the paper the main features of the database were described and its outline explained.

  • Photoinactivation of Staphylococcus aureus using protoporphyrin IX: the role of haem-regulated transporter HrtA
    • Joanna Nakonieczna
    • Monika Kossakowska-Zwierucho
    • Michalina Filipiak
    • Weronika Hewelt-Belka
    • Mariusz Grinholc
    • Krzysztof Piotr Bielawski
    2016 Pełny tekst APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

    Light- and photosensitiser-based antimicrobial photodynamic therapy is a very promising approach to the control of microbial infections. How the phenotypic features of a microorganism affect its response to photosensitiser-based photokilling represents an area of substantial research interest. To understand the mechanisms governing the phenomenon of a strain-dependent response to photodynamic inactivation (PDI), we analysed the possible role of the membrane-located haem transporter HrtA in Staphylococcus aureus. We used a S. aureus strains with an inactivated component of the haem-regulated transporter, HrtA, along with its wild-type counterpart to determine differences in PDI outcome and photosensitiser uptake between the studied isogenic strains. We observed that a lack of HrtA protein potentiates the phototoxic effect towards S. aureus but only when extracellular protoporphyrin IX is used. The observed effect may depend on the function of the HrtA transporter but is likely to result from changed membrane properties following the absence of the protein in the membrane. This indicates that disturbing the membrane properties is an attractive method for improving the efficacy of the photodynamic inactivation of microorganisms.

  • Photovoltaic phenomena in devices with perfluorozincphthalocyanine layer
    • Justyna Szostak
    2016

    The 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 of free charge carriers in all investigated bilayer systems took place at the donor/acceptor junctions. Theoretical models describing the current-voltage behavior of single layer excitonic cells and planar bilayer cells (termed the CFA models) were developed. These models show how free charge carrier mobilities, electrode work functions, dielectric constants and thickness of donor and acceptor layers along with mono and bimolecular recombination constants affect the shape of the current-voltage curves. Knowing this dependence, such important physical quantities as the open-circuit voltage and short-circuit current were correlated with the aforementioned parameters. Subsequently, experimental data collected for all investigated systems were analyzed on the basis of the developed models and the Shockley equivalent circuit model commonly used for organic solar cells. Comparison of the derived CFA models and the SEC model brought some insight on the relation between physical properties of the layers forming the modeled cells and parameters characterizing performance of a cell, such as series and shunt resistances, diode ideality factor or photogeneration and saturation currents. Inter alia, it was possible to explain the illumination dependence of the shunt resistance commonly observed in case of organic solar cells. Moreover, it was shown that one of the layers of the D/A systems may govern the current flow and that the free charge carrier mobility is not necessarily the most important factor influencing the free charge carrier transport through the cell. Surprisingly, the best photovoltaic performance was shown by the single layer CuI/F16ZnPc/BCP/Ag cell. Further increase of the performance of this system is possible if optimization of the phthalocyanine layer is made. Relatively high values of fill factors and open-circuit voltage obtained in the course of this study lead to the conclusion, that F16ZnPc may be a promising material for the applications in the field of organic photovoltaics.

  • PHYSICAL MODEL OF ENERGY-RELATED PROCESSES IN A ROTATING MECHANICAL SYSTEM FOR THE PURPOSES OF DIAGNOSIS OF TRANSMISSION SHAFTS
    • Zbigniew Korczewski
    • Konrad Marszałkowski
    2016 Pełny tekst Journal of Polish CIMEEAC

    In the present article, selected problems connected with identification of slowly changing energy-related processes accompanying high cyclic fatigue of construction materials of simple mechanical systems, with special consideration of transmission shafts, are mentioned for diagnostic purposes. The article also presents physical models of object and processes that in a simplified way reflect mechanical energy transmission from transmission engine to ship propeller.