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Search results for: SHALLOW WATER ACOUSTICS
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Transdermal transport of collagen and hyaluronic acid using water in oil microemulsion
PublicationCollagen and hyaluronic acid (HA) are biopolymers that affect the appearance and condition of the skin. Delivery of these compounds into the skin is highly challenging since have a number of disadvantageous properties, such as high molecular weight and hydrophilicity. Here, we evaluated the transdermal penetration of low and high molecular weight collagen and HA from microemulsions. A number of microemulsion formulations, differing...
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Structural Properties and Water Uptake of SrTi1−xFexO3−x/2−δ
PublicationIn this work, Fe-doped strontium titanate SrTi1−xFexO3−x/2−δ, for x = 0–1 (STFx), has been fabricated and studied. The structure and microstructure analysis showed that the Fe amount in SrTi1−xFexO3−x/2−δ has a great influence on the lattice parameter and microstructure, including the porosity and grain size. Oxygen nonstoichiometry studies performed by thermogravimetry at different atmospheres showed that the Fe-rich compositions...
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Effect of free water on the quasi‑static compression behavior of partially‑saturated concrete with a fully coupled DEM/CFD approach.
PublicationThe work aims to numerically investigate the quasi-static response of partially fluid-saturated concrete under two-dimensional uniaxial compression at the mesoscale. We investigated how the impact of free pore fluid content (water and gas) affected the quasi-static strength of concrete. The totally and partially fluid-saturated concrete behavior was simulated using an improved pore-scale hydro-mechanical model based on DEM/CFD....
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Dispersive Micro‐Solid Phase Extraction of Selected Metals in Water and Food Samples Followed by ICP‐OES Analysis: Method Development, Analysis of Real Samples and Greenness Evaluation
PublicationMultiwalled carbon nanotubes (MWCNTs) are well-known adsorbents because of their high surface area, layered and hollow architecture, hydrophobicity, and multiple and easily accessible adsorption sites. In this study, MWCNTs were used for dispersive micro-solid-phase extraction of various metal chelates in environmental and food samples. Different parameters such as concentration of the chelating reagent, the sorbent dosage, the...
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IEEE International Conference on Acoustics, Speech and Signal Processing
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Actual field corrosion rate of offshore structures in the Baltic Sea along depth profile from water surface to sea bed
PublicationThe paper presents the results of field electrochemical investigations on the corrosion rate of carbon steel in seawater of the Baltic Sea at the location of the Baltic Beta production rig. The measurements were conducted throughout the year in seawater at different depths from the sea surface to the sea bed (about 75 m). The results revealed corrosion aggressiveness of the seawater along the entire depth profile. There was...
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Study of probe signal bandwidth influence on estimation of coherence bandwidth for underwater acoustic communication channel
PublicationA signal transmitted in a shallow Underwater Acoustic Communication (UAC) channel suffers from time dispersion due to the multipath propagation and the refraction phenomena. This causes intersymbol interference of the received signal and frequency-selective fading observed in its spectrum. Coherence bandwidth is one of the key transmission parameters used for designing the physical layer of a data transmission system to minimise...
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Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublicationThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
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Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublicationThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
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Solution of the dike-break problem using finite volume method and splitting technique
PublicationIn the paper the finite volume method (FVM) is presented for the solution of two-dimensional shallow water equations. These equations are frequently used to simulate the dam-break and dike-break induced flows. The applied numerical algorithm of FVM is based on the wave-propagation algorithm which ensures a stable solution and simultaneously minimizes the numerical errors. The dimensional decomposition according to the coordinate...
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Computational analysis of substituent effects on proton affinity and gas-phase basicity of TEMPO derivatives and their hydrogen bonding interactions with water molecules
PublicationThe study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives...
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Optical microsc. images of wear marks on ball (JPG). Reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K07
Open Research DataOptical microscope images of wear zone on the 5mm diam. ceramic ball used in tests as the fixed specimen.Friction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test...
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Optical microsc. images of wear marks on ball (JPG). Reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K06
Open Research DataOptical microscope images of wear zone on the 5mm diam. ceramic ball used in tests as the fixed specimen.Friction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test...
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Optical microsc. images of wear marks on ball (JPG). Reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K02
Open Research DataOptical microscope images of wear zone on the 5mm diam. ceramic ball used in tests as the fixed specimen.Friction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test...
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Optical microsc. images of wear marks on ball (JPG). Reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K06
Open Research DataOptical microscope images of wear zone on the 5mm diam. ceramic ball used in tests as the fixed specimen.Friction and wear tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test...
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Diver Observations by Means of Acoustic Methods
PublicationSearching for objects, especially small ones, moving under water near its the free surface, is always not an easy task. Designing tools for the detection of such targets is a real challenge when the possibility of a terrorist attack is a real threat. This paper presents some aspects of diver detection by means of acoustics methods, both active (side scan sonar) and passive ones (linear receiving antenna). This approach is quite...
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Spatial Analysis of Water Infrastructure Development On Example of Eastern Europe Rural Regions
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Chemometric exploration of sea water chemical component data sets with missing elements
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A comparative study of water distribution and dehydrin protein localization in maturing pea seeds
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Photocatalytic activity of anatase powders for oxidation of methylene blue in water and diluted NO gas
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Assessment of Water Needs of Grapevines in Western Poland from the Perspective of Climate Change
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Changes in Water Quality for Sprinkler Irrigation in Selected Lakes of the Poznan Lake District
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Recent advances in visible light-driven water oxidation and reduction in suspension systems
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Application of Landsat 8 imagery to regional-scale assessment of lake water quality
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Properties of the Langmuir and Langmuir–Blodgett monolayers of cholesterol-cyclosporine A on water and polymer support
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Legislative and criminal law aspects of water protection and prevention of pharmaceuticals accumulation in nature
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Zeta potential, effective diameter and multimodal size distribution in oil/water emulsion
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Ni-MOF-based electrodes: A promising strategy for efficient overall water splitting
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The calculation long-term physical field created by water flow around the ship
PublicationThe paper presents a description of the problems with fluid flow around a ship. Using the described solution of the problem were performed numerical calculations using the boundary element method. Were also presented preliminary results of the calculation of pressure fields at the bottom of the ship, taking into account the impact of the bottom.
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Multistatic sonar for man-made lakes and water-power plants antiterrroristic protection
PublicationArtykuł opisuje nową koncepcję dopplerowskiego sonaru multistatycznego opracowanego w Katedrze Systemów Elektroniki Morskiej Politechniki Gdańskiej. System składa się z sieci hydrofonów rozmieszczonych równomiernie w obserwowanym akwenie oraz ze źródła dźwięku w postaci fali ciągłej o stałej częstotliwości i bardzo niskim natężeniu. Dzięki zastosowaniu specjalnie opracowanych algorytmów przetwarzania sygnałów uzyskuje się poprawną...
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Size-dependent effects of ZnO nanoparticles on the photocatalytic degradation of phenol in a water solution
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Static and dynamic superheated water extraction of essential oil components fromThymus vulgarisL.
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The method of multispectral image processing of phytoplankton processing for environmental control of water pollution
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Investigation of the distribution of imidazolium ionic liquids in the environment - aggregation in water and sorption on minerals
PublicationWpływ cieczy jonowych na środowisko, a w szczególności: migracja do wód powierzchniowych i gruntowych, jak również transport/retencja w gruntach jest determinowany przede wszystkim przez właściwości fizykochemiczne cieczy jonowej jak i właściwości matrycy środowiskowej. Znajomość zjawisk zachodzących w wyniku kontaktu cieczy jonowych z wodą oraz glebą jest jednym z podstawowych warunków oceny ryzyka chemicznego. W pracy wykazano,...
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Possible application of new class of solvents in the purification of water used in hydraulic fracturing
PublicationNowym źródłem energii niekonwencjonalnej w Polsce może być gaz, który jest uwięziony w łupkach. Podczas poszukiwań gazu łupkowego, duże ilości wody wykorzystywanej w procesie szczelinowania hydraulicznego powracają na powierzchnię zanieczyszczone. Istnieje wiele metod usuwania śladowych ilości węglowodorów tj. fizyczne czyli filtracja czy chemiczne czyli zakwaszanie, ale mogą one być nieskuteczne. Pożądana metoda to monitorowanie...
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Problems of inland navigation in Poland in view of integrated water resources management (IWRM)
PublicationW artykule przedstawiono zasady zintegrowane zarządzania gospodarką wodna. Przedstawiono rolę żeglugi środlądowej w gospodarce wodnej Polski i krajów czlonkowskich Unii Europejskiej. Przedstawiono aktualny stan dróg wodnych w Polsce, ograniczenia rozwoju i perspektywy na przyszłośc z punktu widzenia ZZGW.
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Experimental research on effectiveness of the magnetic fluid seals for rotary shafts working in water
PublicationUszczelnianie wałów obrotowych, łożysk i innych zespołów mechanicznych, za pomocą cieczy magnetycznej, tworzącej przegrodę uszczelniającą utrzymywaną siłami pola magnetycznego jest techniką uszczelniania, stosowaną z powodzeniem w urządzeniach pracujących w środowisku gazowym przy ciśnieniu do około 1,0 MPa. Uszczelnienia te umożliwiają również skuteczne rozwiązywanie problemu szczelności przepustów stałych i ruchowych w urządzeniach...
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Chemometric estimation of natural water and sediment using toxicity tests and physicochemical parameters
PublicationOceny jakości wód dokonano na podstawie analizy chemometrycznej bazy danych monitoringowych, składającej się z wyników testów toksyczności i wyników badań parametrów fizykochemicznych. Badaniom poddano próbki wód powierzchniowych pobrane z Jeziora Turawskiego oraz próbki wód podziemnych pobranych z otworów badawczych wykonanych w jego dnie, jak i wokół niego. Zastosowano następujące metody chemometryczne: analizę wiązkową i analizę...
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublicationSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Influence of dissolved organic matter in natural and simulated water on the photochemical decomposition of butylparaben
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Exploring Solanum tuberosum Epoxide Hydrolase Internal Architecture by Water Molecules Tracking
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Ionic liquids for the passive sampling of sulfonamides from water—applicability and selectivity study
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Salinity and pH as factors affecting the passive sampling and extraction of pharmaceuticals from water
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STUDY OF SEASONAL ACOUSTIC PROPERTIES OF SEA WATER IN SELECTED WATERS OF THE SOUTHERN BALTIC
PublicationClimate Research of the globe is a current task, in particular to confirm the general hypothesis of global warming associated with an increase in average temperature. The sea acoustic climate is derived from the concept of climate and refers to the conditions of propagation of acoustic waves in a particular basin. In this paper, the results of systematic measurements of temperature, salinity and velocity distributions of sound...
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Biosilica from sea water diatoms algae—electrochemical impedance spectroscopy study
PublicationHere, we report on an electrochemical impedance study of silica of organic origin as an active electrode material. The electrode material obtained from carbonized marine biomass containing nanoporous diatoms has been characterised by means of XRD, IR, SEM and EIS. Dif- ferent kinds of crystallographic phases of silica as a result of thermal treatment have been found. The electrode is electrochemically stable during subsequent cyclic...
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Operating and economical conditions of cooling water control for marine steam turbines condensers
PublicationW pracy dokonano analizy ekonomicznej i eksploatacyjnej sterowania pracą pomp wody chłodzącej skraplacze turbin okrętowych. Wzięto pod uwagę cechy konstrukcyjne pomp wody chłodzącej skraplacze główne i najnowsze wyniki badań dla takich pomp w zastosowaniach lądowych. Uwagę skupiono przede wszystkim na turbinowych parowych siłowniach okrętowych.
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Environmentally friedly propeller shaft support with the use of water lubricated foil bearings
PublicationW pracy przedstawiono podsumowanie prowadzonych badań w celu opracowania oryginalnej metodyki projektowania oraz technologii wykonania pierwszego w świecie łożyska foliowego smarowanego wodą. Zaprezentowano koncepcje nowego łożyska foliowego poprzecznego oraz opisano opracowany algorytm obliczeniowy wykorzystany do predykcji jego charakterystyk. W rezultacie prowadzonych prac opracowano i przebadano doświadczalnie na stanowisku...
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Removal of organic compounds from water by solvent sublation. Criteria for solvent selection.
PublicationProces flotoekstrakcji zastosowano do usuwania z wody następujących związków organicznych: tetrachlorku węgla, chloroformu, 1,3,5-trimetylobenzenu (mezytylenu), fenolu i 2,4,5-trichlorofenolu. Jako odbierające fazy organiczne użyto: olej mineralny, 1-dekanol, 1-oktanol, octan amylu, dodekan i tetradekan. Mechanizmem decydującym o usuwaniu lotnych związków organicznych (VOC) było odparowanie do wnętrza pęcherzyków gazu, podczas...
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The ice phenomena dynamics of small anthropogenic water bodies in the Silesian Upland, Poland
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Increased water content in bacterial cellulose synthesized under rotating magnetic fields
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