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  • The development of an underwater telephone for digital communication purposes
    • Jan Schmidt
    2016 Pełny tekst HYDROACOUSTICS

    The underwater telephone HTL-10 has been designed to provide voice and data communication between helicopter and submarines using acoustic waves. It works in a half-duplex mode and uses analogue power-efficient modulation in the form of a single side-band, suppressed carrier, in a wide range of frequencies. It generates the transmitted signal, and processes the received signals. It is implemented with the use of digital signal processing techniques. Although it was designed several years ago, the flexible structure of the underwater telephone ensures a convenient platform for the implementation of various types of communication, as well as testing. This ability is due to the particular characteristics of the digital signal-processing module, which was designed by the author, both in hardware and software. The main elements of the module consist of the fixed-point signal processor, and the floating-point high performance digital signal processor. The article demonstrates the ability to adapt HTL-10 to implement digital communication in shallow waters, with a robust low data rate spread spectrum approach.

  • The diagnostic ambiguity of the impact test in empirical research of circular saw blades for wood
    • Kazimierz Orłowski
    • Anna Danuta Kaczmarek-Penia•kova
    2016 Pełny tekst Mechanik

    Zachowanie piły podczas pracy – zarówno w trakcie przecinania, jak i na biegu luzem – zależy w dużym stopniu od konstrukcji piły i częstotliwości własnych narzędzi, które można określać doświadczalnie za pomocą testu harmonicznego bądź impulsowego. Wyniki badań wykazały, że ten ostatni nie gwarantuje prawidłowego przypisania częstotliwości charakterystycznych widma do odpowiadających im rzeczywistych postaci drgań wynikającym z testu harmonicznego

  • The difficulties in polybrominated diphenyl ethers identification by GC-EI-MS technique
    • Monika Śmiełowska
    • Bożena Zabiegała
    2016

    Awareness about the harmful effects of brominated flame retardants on living organisms increases mainly due to link their presence in the human environment with health disorders. Therefore is a need to conduct research aimed at content control of these chemicals in the environment. Recent improvements in injection techniques and mass spectrometer ionization methods have led to a variety of options to determine PBDEs in environmental samples. Some difficulties in qualitative and quantitative analysis still make dekaBDE congener (BDE-209). Modeling studies aimed at selecting the optimal conditions for the separation and identification of selected PBDEs patterns have been carried out. The results are an introduction to the study of real environmental samples. Using technique was gas chromatography with electronionization-mass spectrometry.

  • The dying medium temperature impact on the final moisture content of pine wood at constant drying time
    • Aleksandra Konopka
    • Jacek Barański
    2016 Annals of WULS, Forestry and Wood Technology

    The results of final moisture content of pine wood (Pinus sylvestris L.) after drying process are presented. The wood in the experiments was taken from the northern part of Pomeranian region in Poland. The drying process was performed in the experimental chamber equipped with the micro-jet heat exchanger. The air at temperatures of 40°C, 60°C, 80°C, 100°C and 120°C with relative humidity about 60% and atmospheric pressure was the drying agent. The volumetric flow rate was constant and equal to 7.1 m3/h, while the average flow velocity of the drying agent was equal to 3.9 m/s. The drying time, equal to 345 minutes, was also constant in each case of study. The obtained results allowed to determine drying rate for each temperature of drying medium.

  • The dynamics of the total output of the fishery sector: The case of Indonesia
    • Ubaidillah Zuhdi
    2016

    The purpose of this study is to analyze the dynamics of the total output of the Indonesian fishery industry when the changes of the final demand occur. This study employs a demand-pull Input-Output (IO) quantity model, one of the calculation tools in the IO analysis, as an analysis instrument. Two conditions are noticed in calculation and analysis parts, namely (1) “whole sector change”, and (2) “pure change”. An initial period in this study is 2008. The results show that, in both conditions, the discussed sector has similar patterns, namely this industry receives the positive impacts from scenarios 1 and 3 while the negative impact is obtained from scenario 2. The results also explain that, in both conditions, the biggest positive impact for the analyzed sector is given by scenario 3, the change of households and non-profit private institutions consumptions.

  • The dynamics of the total output of the Japanese fisheries sector: An analysis using input-output approach
    • Ubaidillah Zuhdi
    2016

    The purpose of this study is to investigate the dynamics of the total output of the fisheries industry when the changes of the final demand occur. This study focuses on the case of Japan. This study employs a demand-pull Input-Output (IO) quantity model, one of the calculation instruments in the IO analysis, as an analysis tool. Two conditions are included in calculation and analysis parts, namely (1) “whole sector change”, and (2) “pure change”. An initial period in this study is 2005. The results show that, in both conditions, the analyzed sector has similar patterns, namely this industry obtains the positive impacts from scenarios 1, 3, and 4 while the negative impact is received from scenario 2. The results also expose that, in both conditions, the biggest positive impact for the discussed sector is given by scenario 4, the modification of the consumption expenditures of the private.

  • The dynamics of the total outputs of Japanese information and communication technology sectors: A further study
    • Ubaidillah Zuhdi
    2016

    The purpose of this study is to continue the previous studies which discussed the impacts of the changes of final demands on the total outputs of the Information and Communication Technology (ICT) sectors of the specific country. More specifically, this study aims to conduct a deeper analysis regarding these impacts. This study focuses on the case of Japan. This study employs a demand-pull Input-Output (IO) quantity model, one of the calculation tools in the IO analysis, as an analysis instrument. Two conditions are included in calculation and analysis parts, namely (1) “whole sector change”, and (2) “pure change”. An initial period in this study is 2005. The results show that, in both conditions, the discussed sectors have similar patterns, namely these industries receive the positive impacts from scenarios 1, 3, and 4 while the opposite impact is obtained from scenario 2. This negative impact also appeared in the previous studies. The results also expose that, in both conditions, the biggest positive impacts for analyzed sectors is given by scenario 4, the modification of the consumption expenditures of the private. Compared with the previous studies, these are new findings.

  • The effect of a belt position in the spindle driving system on critical rotational speeds
    • Kazimierz Orłowski
    • Karol Duchnicz
    2016 Annals of WULS, Forestry and Wood Technology

    The aim of this paper was to examine how the belt pulley position affects critical rotational speeds of the modernized spindle of the sliding table saw Fx3. Methodology of determination of critical rotational speeds of the spindle in a function of the spindle design features and its driving system is presented. Spindles in these kind of machine tools are mainly driven with V-belts, and the pulleys on the spindles might be positioned: usually on the rear end, between bearings or on the spindle nose between a circular saw blade and the fore bearing. Numerical computations with the FEM (Finite Element Method) of the spindle deformations were carried out for five case studies of the position of the force acting on the pulley. The obtained results revealed that the average ratio value of a critical rotational speed to the maximum rotational speed ncr / nmax = 2.414 fulfills the literature recommendations.

  • The effect of alkyl chain length on synergistic effects in micellization and surface tension reduction in nonionic gemini (S-10) and anionic surfactants mixtures
    • Aleksandra Trawińska
    • Elżbieta Hallmann
    • Krystyna Mędrzycka
    2016 COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS

    Mixtures of nonionic gemini surfactant S-10 ( α, α'-[2,4,7,9-tetrametyl-5-decyne-4,7-diyl]bis[ω-hydroxy -polioxyetylene] with anionic SRS (sodium alkylsulfates) and SRSO3 (sodium alkylsulfonates) of different alkyl chain length (from 10 to 14 carbon atoms) were investigated. Surface tension measurements were used to find the cmc values and other adsorption parameters. The Clint, Rubingh’s and Rosen theories were applied for evaluation of the synergistic effects in mixed films and mixed micelles formation. It has been documented that in the process of micellization strong synergy exists, while in mixed film formation it is not so evident. In mixtures of S-10 with monomeric surfactants, the synergistic interactions in mixed micelles formation increase with the chain length of monomeric surfactant. The composition of mixed films is different than the composition of mixed micelles, because molar fraction of S-10 in monolayers is much higher than its contribution in mixed micelles at the same bulk composition. The size of micelles is the biggest for S-10 and in case of surfactants mixtures is smaller than that, for individual components.

  • The effect of anthropogenic activity on BTEX, NO2, SO2, and CO concentrations in urban air of the spa city of Sopot and medium-industrialized city of Tczew located in North Poland
    • Mariusz Marć
    • Michalina Bielawska
    • Vasil Simeonov
    • Jacek Namieśnik
    • Bożena Zabiegała
    2016 Pełny tekst ENVIRONMENTAL RESEARCH

    The major goal of the present study is to compare the air quality of two urban locations situated in Northern Poland – the spa City of Sopot and the medium-industrialized city of Tczew using chemometric methods. As a criterion for the assessment of atmospheric air quality, measurements of benzene, toluene, ethylbenzene and total xylenes were used (collected from atmospheric air using diffusion-type passive samplers) as well as measurements of inorganic compounds - CO, NO2 and SO2, which were subject to routine control and determined by means of automatic analysers. Studies related to determination of defined chemical compounds in the urban air in the monitored area were performed from January 2013 to December 2014. By interpreting the results obtained and using basic multivariate statistical tools (cluster analysis and principal components analysis), major sources of emissions of determined pollutants in the air in urbanized areas were defined. The study also shows the potential influence of the sea breeze on concentrations of chemical compounds in the atmospheric air in the spa city of Sopot.

  • The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
    • Joanna Mioduska
    • Anna Zielińska-Jurek
    • Marcin Janczarek
    • Jan Hupka
    2016 Pełny tekst Journal of Nanomaterials

    Series ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover, the amount ofWO3 crystalline phase and amorphous phase inWO3/TiO2 aggregates, as revealed by XRD analysis, was dependent on the calcination temperature.TheWO3/TiO2 samples with 8 mol% load ofWO3 in respect to TiO2 calcinated at 500 and 800∘C possess the highest photocatalytic activity in reaction of phenol degradation, which is about 1.2 and 1.5 times that with calcination at 400∘C. The increase in calcination temperature above 400∘C resulted in increase of WO3 crystallinity and reduction of the amount of amorphous phase in the nanocomposite structure. Moreover, the annealing of nanocomposites above 700∘C decreases the value of optical band gap energies of obtainedWO3/TiO2 nanomaterials.

  • The Effect of Circular Saw Blade Clamping Diameter on its Resonant Frequencies
    • Anna Danuta Kaczmarek-Penia•kova
    • Kazimierz Orłowski
    • Lubomir Javorek
    2016 Applied Mechanics and Materials

    In this paper results of comparison of characteristic resonant frequencies of circular saw blades as a function of the saw clamping diameter from the impact test are presented. Obtained results revealed that proportionally with the increase of the saw clamping diameter also the dynamical stiffness of the saw blade increased. As a consequence of that the resonant frequencies of the saw blade move to higher values. Moreover, with the increase of the saw blade clamping diameter for higher frequencies of forcing vibrations of the saw blade the amplitude of vibration are expected to be decreased.

  • The effect of gold shape and size on the properties and visiblelight-induced photoactivity of Au-TiO2
    • Anna Gołąbiewska
    • Anna Malankowska
    • Marcin Jarek
    • Wojciech Lisowski
    • Grzegorz Nowaczyk
    • Stefan Jurga
    • Adriana Zaleska-Medynska
    2016 APPLIED CATALYSIS B-ENVIRONMENTAL

    tIn the present investigation, TiO2modified with a different geometry and size of gold particles, suchas nanospheres (NSPs), nanostars (NSTs) and nanorods (NRs), were prepared by the immobilizationmethod. The effect of the gold shape, size and TiO2matrix type (TiO2microspheres or rutile TIO-6 TiO2)were systematically investigated. The obtained photocatalysts were thoroughly characterized by UV–visdiffuse-reflectance spectroscopy (DRS), BET surface area measurements, scanning electron microscopy(SEM), scanning transmission microscopy (TEM), X-ray diffraction analysis (XRD), and X-ray photoelec-tron spectroscopy (XPS). The photocatalytic activity under visible light ( > 420 nm) has been estimatedin phenol degradation reaction in an aqueous phase. The significantly high photocatalytic activity undervisible light irradiate as demonstrated by the TiO2sample modified by spheres of gold. The average rateof phenol decomposition was 1.9 mol dm−3min−1and was three-times higher compared to the pristineTiO2amorphous microspheres. On the other hand the photocatalytic activity was relatively lower and was0.38 and 0.27 mol dm−3min−1for nanorods and nanostars deposited on the amorphous form of TiO2microspheres, respectively. The visible light activity decreased in following order: (NSPs)> (NRs)> (NSTs).The obtained photocatalytic efficiency of samples was ascribed to the geometry and the size effect ofthe enhanced and the possible mechanism for this was discussed in detail. Furthermore, in this work weshow the effect of calcination temperature on the structure of gold NPs, NRs and NSs before and aftermodification on the morphology and photocatalytic activity of Au-TiO2.

  • The effect of high pressure on formation of volatile amines in minced meat of cod (Gadus morhua)
    • Edyta Malinowska-Pańczyk
    • Ilona Kołodziejska
    2016 Pełny tekst EUROPEAN FOOD RESEARCH AND TECHNOLOGY

    The effects of high pressure at subzero temperature (193 MPa, at −20 °C) on inactivation of natural microflora of cod meat and degradation of trimethylamine oxide (TMAO) to trimethylamine (TMA) during refrigerated storage and to dimethylamine (DMA) and formaldehyde (FA) during frozen storage were investigated. The content of TMA, DMA and FA in cod meat did not change immediately after pressure treatment. During 40 days of frozen storage of pressurized meat at −5 °C, concentration of DMA-N and FA was, respectively, about 10 and 7 times lower than in the stored unpressurized meat. It is the result of pressure-induced inactivation of cod meat TMAOase. There was no correlation between the total numbers of bacteria and TMA-N content. The total bacterial count has increased during refrigerated storage of pressurized meat, although for a short period of time more slowly than in the untreated samples. During refrigerated storage, the accumulation of TMA-N in pressurized samples was much lower than in unpressurized meat. The pressure treatment of fish meat leads to considerable reduction in enzymatic and bacterial decomposition of TMAO to DMA and TMA, respectively. Therefore, such processing can improve sensory quality of meat and allow to extend its shelf life.

  • The effect of metal cluster deposition route on structure and photocatalytic activity of mono- and bimetallic nanoparticles supported on TiO2 by radiolytic method
    • Joanna Nadolna
    • Anna Gołębiewska
    • Paweł Mazerski
    • Tomasz Klimczuk
    • Hynd Remita
    • Adriana Zaleska-Medynska
    • Marek Klein
    • Anna Golabiewska
    2016 APPLIED SURFACE SCIENCE

    TiO2 (P25) was modified with small and relatively monodisperse mono- and bimetallic clusters (Ag, Pd, Pt, Ag/Pd, Ag/Pt and Pd/Pt) induced by radiolysis to improve its photocatalytic activity. The as-prepared samples were characterized by X-ray fluorescence spectrometry (XRF), photoluminescence spectrometry (PL), diffuse reflectance spectroscopy (DRS), X-ray powder diffractometry (XRD), scanning transition electron microscopy (STEM) and BET surface area analysis. The effect of metal type (mono- and bimetallic modification) as well as deposition method (simultaneous or subsequent deposition of two metals) on the photocatalytic activity in toluene removal in gas phase under UV–vis irradiation (light-emitting diodes- LEDs) and phenol degradation in liquid phase under visible light irradiation (λ > 420 nm) were investigated. The highest photoactivity under Vis light was observed for TiO2 co-loaded with platinum (0.1%) and palladium (0.1%) clusters. Simultaneous addition of metal precursors results in formation of larger metal nanoparticles (15-30 nm) on TiO2 surface and enhances the Vis-induced activity of Ag/Pd-TiO2 up to four times, while the subsequent metal ions addition results in formation of metal particle size ranging from 4 to 20 nm. Subsequent addition of metal precursors results in formation of BNPs (bimetallic nanoparticle) composites showing higher stability in four cycles of toluene degradation under UV-Vis. Obtained results indicated that direct electron transfer from the BNPs to the conduction band of the semiconductor is responsible for visible light photoactivity, whereas superoxide radicals (such as O2•− and radical dotOOH) are responsible for pollutants degradation over metal-TiO2 composites.

  • The effect of social media communication on consumer perceptions of brands
    • Bruno Schivinski
    • Dariusz Dąbrowski
    2016 Journal of Marketing Communications

    Researchers and brand managers have limited understanding of the effects social media communication has on how consumers perceive brands. We investigated 504 Facebook users in order to observe the impact of firm-created and user-generated (UG) social media communication on brand equity (BE), brand attitude (BA) and purchase intention (PI) by using a standardized online survey throughout Poland. To test the conceptual model, we analyzed 60 brands across three different industries: non-alcoholic beverages, clothing and mobile network operators. When analyzing the data, we applied the structural equation modeling technique to both investigate the interplay of firm-created and user-generated social media communication and examine industry-specific differences. The results of the empirical studies showed that user-generated social media communication had a positive influence on both brand equity and brand attitude, whereas firm-created social media communication affected only brand attitude. Both brand equity and brand attitude were shown to have a positive influence on purchase intention. In addition, we assessed measurement invariance using a multi-group structural modeling equation. The findings revealed that the proposed measurement model was invariant across the researched industries. However, structural path differences were detected across the models.

  • The effect of the exposure-in-oil on the contact of the polymers forming sliding layers in hydrodynamic bearings. Wpływ ekspozycji w oleju na kąt zwilżania polimerów stosowanych na warstwy ślizgowe w łożyskach hydrodynamicznych.
    • Justyna Zorn
    • Michał Wasilczuk
    2016 Pełny tekst TRIBOLOGIA

    Polimery stosowane jako warstwy ślizgowe w hydrodynamicznych łożyskach wzdłużnych to zazwyczaj tworzywa termoplastyczne charakteryzujące się relatywnie wysokimi wartościami kątów zwilżania w porównaniu z metalami. Metale, w tym również Babbitt czy inne stopy łożyskowe, cechują niskie wartości kątów zwilżania. Im niższy kąt, tym powierzchnia lepiej się zwilża. Tworzywa sztuczne wykorzystywane w węzłach tribologicznych mających zapewnić jak niższy współczynnik tarcia, czyli na przykład politetra-fluoroetylen lub jego kompozyty cechują kilkukrotnie wyższe wartości kątów zwilżania w porównaniu ze stopami łożyskowymi. W opisanym poniżej badaniu przedstawiono wpływ ekspozycji w oleju na kąt zwilżania polimerów stosowanych na warstwy ślizgowe w łożyskach hydrodynamicznych. Przeprowadzone badanie pokazało korzystny wpływ oleju na obniżenie kąta zwilżania. Polymers used as the sliding layers of hydrodynamic thrust bearings are typically thermoplastics characterized by relatively high values of contact angles when compared with metals. Metals, including Babbitt, or other bearing alloys, are characterized by low values of the contact angles. The lower the angle, the better the surface is wetted. Plastics used in tribological pairs to ensure a lower coefficient of friction, that is, for example, polytetrafluoroethylene (PTFE) or its composites, have several times higher contact angles compared to the bearing alloys. The research described below shows the effect of the exposure-in-oil contact angle of the polymer layer applied on a hydrodynamic sliding bearing. The conducted study showed the beneficial effects of oil on the reduction of the contact angle.

  • THE EFFECT OF WET UNDERWATER WELDING ON COLD CRACKING SUSCEPTIBILITY OF DUPLEX STAINLESS STEEL
    • Jerzy Łabanowski
    • Karolina Prokop-Strzelczyńska
    • Grzegorz Rogalski
    • Dariusz Fydrych
    2016 Pełny tekst Advances in Materials Science

    ABSTRACT The present work was conducted to assess the weldability of duplex stainless steel in underwater conditions. Metal manual arc welding (MMA) with the use of coated electrodes was used in the investigations. Tekken weldability tests were performed underwater at 0.5 m depth and in the air. Nondestructive tests, metallographic examinations of welds, ferrite content assessment in microstructure and hardness test were performed. The good weldability at underwater conditions of duplex stainless with the use of MMA method was confirmed, however difficulties in stable arc burning were revealed

  • The Effectiveness of Polymer Damper in Damage Reduction of Temporary Steel Grandstand
    • Natalia Lasowicz
    • Robert Jankowski
    2016 Key Engineering Materials

    A large number of accidents involving damage of temporary grandstands during different types of events were observed in the past. The aim of the paper is to analyse numerically the effectiveness of a polymer damper in damage reduction of a temporary steel scaffolding grandstand exposed to dynamic load due to jumping. The element has been installed as a diagonal one at the back part of the structure. The method has been compared with the typical solution of strengthening the grandstand with the diagonal stiffener of tubular cross section. The results of the study clearly show that the response of a temporary steel grandstand equipped with a diagonal damper as well as with the diagonal stiffener is substantially different. The application of the polymer damper leads to considerable reduction in the level of measured accelerations due to the increased structural damping preventing from damage.

  • The Ellenbogen's "Matter as Software" Concept for Quantum Computer Implementation: II Bonding Between the C60 and X@C60 Molecules as Available Molecular Building Blocks (MBBs) for Tip-Based Nanofabrication (TBN) of Quantum Computing Devices
    • Aleksander Herman
    2016 Quantum Matter

    The binding energy, BE of the X@C60-X@C60 homodimer and the X@C60-Y@C60 heterodimer resulting from the bond formation between the occupied X@C60 MBB and the C60 molecule was studied by means of semiempirical PM7 calculations, where X and Y denote atoms from H to Bi, excluding Tc and lanthanides. All possible combinations of N = 68 guest atoms were considered, which resulted in K = 2346 of different calculated dimers of (X@C60-Y@C60) or (X@C60-X@C60)-type. The obtained results showed that all possible combinations of the guest elements are stable, with the average binding energy, BE equal to –3.8±1.8 eV. In the present paper we confirm our previous suggestion that the C60 and X@C60 host-guest molecules are almost ideal MBBs for the implementation of “Matter as Software” concept in quantum computing.