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Search results for: marine
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Polymer journal bearings behaviour research under limited lubrication and cooling conditions conducted on high torque test rig
PublicationPolymer journal bearings are frequently used as a water-lubricated bearings of small marine units’ propeller shafts . Choice of these bearings is based on their simple construction and relatively low purchase and maintenance costs. Although properly designed and installed water lubricated bearings may well last for over a decade, rapid wear or failure of these bearings can be observed...
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Elastic Fender-Dolphin Interaction for Economic Design of Berthing Dolphins
PublicationThe study addresses the question of the possible design benefits when considering the interaction between a modern marine modular rubber fender and a steel tubular pile substructure of a berthing dolphin. Absorption of the berthing kinetic energy of the vessel by a dualelasticity pile-fender berthing system is described in detail using the interactive treatment method (ITM). Application of the ITM is illustrated by a calculative...
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Bartłomiej Luks dr
PeopleI'm a snow researcher, working in the Arctic for almost 20 years. I've started as a field assistant on a geological expedition to Bellsund (Spitsbergen), then did my masters on soil pollution in the vicinity of Polish Polar Station Hornsund and PhD on dynamics of snowpack in the SW Spitsbergen. Since 2013 I'm an Assistant Professor at the Department of Polar and Marine Research IG PAS in Warsaw. My main research interests are the...
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Evaluation of antimicrobial activities of powdered cuttlebone against Klebsiella oxytoca, Staphylococcus aureus, and Aspergillus flavus
PublicationBackground: The presence of medicines in the environment is considered as a serious threat to the human health. The entrance of these substances into the water sources causes soil pollution, which eventually leads to the environmental pollution and it creates some problems for the public health. Also, increasing antibiotic resistant bacteria has attracted the attention of researchers to the use of natural resources such as marine...
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Preliminary Testing of the Influence of Modified Polycaprolactones on Anabaena Variabilis Growth in Seawater
PublicationSeveral new biodegradable polymer materials have recently come onto the global market. Mostly the results on degradation kinetic studies are presented. This paper suggests using one of the tests to estimate the impact of polymer packaging material on sea life. The microorganism chosen was Anabaena variabilis (identified in many waters, including those of the Baltic Sea, especially in the Gulf of Gdansk and Puck Bay; this cyanobacterium...
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Wpływ stosowanych praktyk rolniczych na dopływ wód podziemnych oraz azotanów do Zatoki Puckiej
PublicationEutrophication of marine basins associated with submarine groundwater discharge is currently one of the most important challenges in modern coastal hydrogeology, and is classified as a serious global environmental problem. A particular source of groundwater pollution is agricultural activity, which is commonly carried out in the coastal zone. Research was conducted on a representative part of the Bay of Puck watershed, dominated...
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Plasticity of Bead-On-Plate Welds Made with the Use of Stored Flux-Cored Wires for Offshore Applications
PublicationExtreme atmospheric conditions in the marine and offshore industry are harmful to engineering materials, especially to welded joints, and may cause degradation of their properties. This article presents the results of research on the plasticity of bead-on-plate welds made using two types of seamless, copper plated flux-cored wires. Before welding, spools with wire were stored for 1 month in two distinct locations with different...
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Antibiotic resistance and prevalence of class 1 and 2 integrons in Escherichia coli isolated from two wastewater treatment plants, and their receiving waters (Gulf of Gdansk, Baltic Sea, Poland)
PublicationIn this study, antimicrobial-resistance patterns were analyzed in Escherichia coli isolates from raw (RW) and treated wastewater (TW) of two wastewater treatment plants (WWTPs), their marine outfalls (MOut), and mouth of the Vistula River (VR). Susceptibility of E. coli was tested against different classes of antibiotics. Isolates resistant to at least one antimicrobial agent were PCR tested for the presence of integrons. Ampicillin-resistant...
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Bacterial Community Structures in Freshwater Polar Environments of Svalbard
PublicationTwo thirds of Svalbard archipelago islands in the High Arctic are permanently covered with glacial ice and snow. Polar bacterial communities in the southern part of Svalbard were characterized using an amplicon sequencing approach. A total of 52,928 pyrosequencing reads were analyzed in order to reveal bacterial community structures in stream and lake surface water samples from the Fuglebekken and Revvatnet...
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Microplastics in water resources: Global pollution circle, possible technological solutions, legislations, and future horizon
PublicationBeneath the surface of our ecosystems, microplastics (MPs) silently loom as a significant threat. These minuscule pollutants, invisible to the naked eye, wreak havoc on living organisms and disrupt the delicate balance of our environment. As we delve into a trove of data and reports, a troubling narrative unfolds: MPs pose a grave risk to both health and food chains with their diverse compositions and chemical characteristics....
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GUIDED WAVES IN SHIP STRUCTURAL HEALTH MONITORING – A FEASIBILITY STUDY
PublicationShips and offshore structures operate in a severe corrosion degradation environment and face difficulty in providing long- lasting corrosion protection. The Classification Societies recommend regular thickness measurements leading to structural component replacements, to ensure structural integrity during service life. The measurements are usually performed using ultrasonic thickness gauges and such an approach requires multiple...
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The Application of a Mobile Unmanned Device for Monitoring Water and Sediment Pollution in the Port of Gdynia
PublicationPollution in the Port of Gdynia can encompass various types of substances and contaminants that affect the quality of water and sediment in this region. Ships entering and leaving the port can release pollutants such as oil, fuel, waste, and chemicals into the water. Controlling and monitoring these pollutants is a crucial part of environmental stewardship. In recent years, uncrewed units have been increasingly in use for in situ...
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Seabed Topography Changes in the Sopot Pier Zone in 2010–2018 Influenced by Tombolo Phenomenon
PublicationBathymetric surveys of the same body of water, performed at regular intervals, apart from updating the geospatial information used to create paper and electronic maps, allow for several additional analyses, including an evaluation of geomorphological changes occurring in the coastal zone. This research is particularly important in places where the shape of the coastal zone has been violently disturbed, including by human activity....
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EVALUATION OF EFFECTIVENESS OF WATERJET PROPULSOR FOR A SMALL UNDERWATER VEHICLE
PublicationT he goal of the project described is to replace the existing propulsion system of a small underwater vehicle with a solution less prone to mechanical damage and ensuring a lower risk of the entanglement of fibrous objects suspended in the body of water. Four typical marine screws are utilised in the current design of the vehicle. One possible solution of the problem is the application of waterjet propulsors located...
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The abrasive wear resistance of coatings manufactured on high-strength low-alloy (HSLA) offshore steel in wet welding conditions
PublicationSome marine and offshore structure elements exploited in the water cannot be brought to the surface of the water as this will generate high costs, and for this reason, they require in-situ repairs. One of the repair techniques used in underwater pad welding conditions is a wet welding method. This paper presents an investigation of the abrasive wear resistance of coatings made in wet welding conditions with the use of two grades...
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Spatial Differences in the Chemical Composition of Surface Water in the Hornsund Fjord Area: A Statistical Analysis with A Focus on Local Pollution Sources
PublicationSurface catchments in Svalbard are sensitive to external pollution, and yet what is frequently considered external contamination may originate from local sources and natural processes. In this work, we analyze the chemical composition of surface waters in the catchments surrounding the Polish Polar Station in Svalbard, Hornsund fjord area. We have pooled unpublished and already published data describing surface water composition...
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ENERGY ANALYSIS OF THE PROPULSION SHAFT FATIGUE PROCESS IN A ROTATING MECHANICAL SYSTEM PART II IDENTIFICATION STUDIES – DEVELOPING THE FATIGUE DURABILITY MODEL OF A DRIVE SHAFT
PublicationThe article presents a continuation of research carried out concerning identification of energy consequences of mechanical fatigue within a propeller shaft in a rotating mechanical system, while working under conditions of the loss of the required alignment of shaft lines. Experimental research was carried out on a physical model reflecting a full-sized real object: i.e., the propulsion system of the ship. It is proven, by means...
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Reinforced concrete thin wall dome after eighty years of operation in maritime climate environment
PublicationThe paper presents a description of the construction elements of the Gdynia Seaport main hall dome. Firstly, it provides information about the technical condition of the dome’s structure. Secondly, it examines the strength analysis of the thin-walled reinforced concrete dome covering. Throughout the last 80 years the building has been exposed to an unfavourable marine climate. The analysis of the state of stress and deformations...
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Multi-layered mineral glass units used as viewport elements of underwater ship structures
PublicationIn the paper, Authors deals with viewport elements of underwater marine constructions. If a single-plate viewport constructions are considered, big thicknesses of the glass plate are required to resist the pressure. To build the viewports from the commercially accessible glass panes, multi-layered glass units are proposed in the paper. Numerical calculations are presented, summarized and compared with experimental tests. Focusing...
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Research on water lubricated main shaft bearings in conditions of improper lubrication and cooling conducted on high torque real-life scale bush test rig
PublicationWater lubricated polymer bushes find increasingly popular use in the sliding bearings of marine propellers, water turbines and pump shafts. Such popularity is partly due to their simple construction which also means relatively affordable price. In addition, properly designed and installed water lubricated bearings may well last for over a decade. However, in practical experience one may also observe cases of rapid wear...
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TARGOIOWISKO – Targi Pracy online 19-22 maja 2020
EventsBiuro Karier PG zaprasza na TARGOIOWISKO - Wydziałowe Targi Pracy online. Zaproszone firmy przedstawią oferty pracy, praktyk i staży dla studentów i absolwentów.
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Zastosowanie testu biologicznego Microtox do oceny skuteczności działania oczyszczalni ścieków bytowo-przemysłowych
PublicationOcena efektywności procesu oczyszczania ścieków z zastosowaniem biotestu Microtox® na przykładzie wybranej oczyszczalni Powszechnie praktykowanym sposobem wprowadzania ścieków oczyszczonych do środowiska jest ich punktowy zrzut do wód powierzchniowych. Różnorodność działalności prowadzonej w ramach współczesnej gospodarki sprawia, że do oczyszczalni docierają nie tylko substancje, których oznaczanie jest wymagane przez przepisy...
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EMISJA AKUSTYCZNA JAKO SYGNAŁ DIAGNOSTYCZNY ODWZOROWUJĄCY ZMĘCZENIOWE ZUŻYCIE WARSTW ŚLIZGOWYCH PANWI ŁOŻYSK GŁÓWNYCH I KORBOWYCH SILNIKÓW O ZAPŁONIE SAMOCZYNNYM
PublicationW artykule przedstawiono wyniki badań laboratoryjnych, z których wynika, że emisja akustyczna (EA) może być uznana za sygnał diagnostyczny, przydatny do identyfikacji stanu technicznego łożysk głównych i korbowych okrętowych silników o zapłonie samoczynnym. Wykazano w nim bowiem, że parametry emisji akustycznej takie jak: czas rejestracji, energia sygnału, amplituda sygnału, ilość przekroczeń poziomu dyskryminacji, czas narastania,...
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Automatic Identification System (AIS) Dynamic Data Integrity Monitoring and Trajectory Tracking Based on the Simultaneous Localization and Mapping (SLAM) Process Model
PublicationTo enhance the safety of marine navigation, one needs to consider the involvement of the automatic identification system (AIS), an existing system designed for ship-to-ship and shipto- shore communication. Previous research on the quality of AIS parameters revealed problems that the system experiences with sensor data exchange. In coastal areas, littoral AIS does not meet the expectations of operational continuity and system availability,...
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Study on Dry Sliding Wear and Friction Behaviour of Al7068/Si3N4/BN Hybrid Composites
PublicationHybrid aluminium metal matrix composites have the potential to replace single reinforced aluminium metal matrix composites due to improved properties. Moreover, tribological performance is critical for these composites, as they have extensive application areas, such as the automotive, aerospace, marine and defence industries. The present work aims to establish the tribological characteristics of Al7068/Si3N4/BN hybrid metal matrix...
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An analytical four-layer horizontal electric current dipole model for analysing underwater electric potential in shallow seawater
PublicationThe paper presents a new analytical four‑layer (air–water–bottom–non‑conductive layer) horizontal electric dipole model which allows an accurate approximation of ship’s Underwater Electric Potential (UEP) from a sufficient depth in shallow coastal marine waters. The numerical methods, usually Finite Element Method (FEM) or Boundary Elements Method (BEM), are typically used to estimate the electric field and the distribution of...
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Distribution and extent of benthic habitats in Puck Bay (Gulf of Gdańsk, southern Baltic Sea)
PublicationThe majority of the southern Baltic Sea seabed encompasses homogenous soft-bottom sediments of limited productivity and low biological diversity, but shallow productive areas in the coastal zone such as wetlands, vegetated lagoons and sheltered bays show a high variety of benthic habitat types offering favourable biotopic conditions for benthic fauna. Within Polish marine areas, semi-enclosed Puck Bay (the western part of the...
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Seasonal changes in organotin compounds in water and sediment samples from the semi-closed Port of Gdynia
PublicationThe effect of seasonal changes on the distribution of organotin compounds (OTC) in the sediments and seawaterfrom the docks of the Port of Gdynia was investigated. Sediment and seawater samples were collectedfrom four industrial docks in February (winter) and June (summer) in 2009. The samples were analyzed forbutyltin, phenyltin, octyltin, and tricyclohexyltin (total of 9 OTC derivatives). The fine fraction (b0.063 mm)accumulated...
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Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
PublicationSeveral studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different...
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Seasonal and spatial differences in metal and metalloid concentrations in the snow cover of Hansbreen, Svalbard
PublicationMetals and metalloids in snow on glaciers, depending on the season of deposition, may come from various sources: local rock dust (erosion of the geological substratum), marine aerosol, local human activity (e.g. fuel combustion, waste incineration) and long-range atmospheric transport. Hansbreen glacier, located close to the Polish Polar Station in Svalbard, is a perfect site to study metals and metalloids: it has complex geological...
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Phospholipids as potential prevention factor in carcinogenesis
PublicationPhospholipids are a group of complex lipids, which can be used in cancer chemoprevention. Glicerophospholipids are composed of fatty acids esterified to a glycerol backbone, a phosphate group and a hydrophilic residue such as: cho- line, ethanoloamine, serine or inositol. In the sn-2 position of glicerophospholipid usually there are unsaturated fatty acids, i.e. linolenic acid, while in the sn-1 position more typi- cal are saturated...
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Nondestructive global corrosion measurement using guided wavefield data
PublicationMetallic structures often face degradation, and corrosion ranks among the most prevalent forms of deterioration. Accurate quantification of corrosion is crucial, especially for structures exposed to harsh environmental conditions, such as marine vessels and offshore installations. Because the traditional measurement methods based on scanning by ultrasonic gauge are time-consuming and provide only rough information on the thickness...
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Analysis of Transformation Methods of Hydroacoustic and Optoelectronic Data Based on the Tombolo Measurement Campaign in Sopot
PublicationMeasurements in the coastal zone are carried out using various methods, including Global Navigation Satellite Systems (GNSS), hydroacoustic and optoelectronic methods. Therefore, it is necessary to develop coordinate transformation models that will enable the conversion of data from the land and marine parts to one coordinate system. The article presents selected issues related to the integration of geodetic and hydrographic data....
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Impact of a newly-formed periglacial environment and other factors on fresh water chemistry at the western shore of Admiralty Bay in the summer of 2016 (King George Island, Maritime Antarctica)
PublicationThis study provides a comprehensive analysis of the inorganic chemistry of flowing water at the western shore of Admiralty Bay. In the water samples, ions, and major and trace metals (and B)were detected and quantified. Additionally, the parameters of pH, specific electrolytic conductivity (SEC25) and total organic carbon (TOC) were determined. Moreover, multivariate data set was created and Principal Component Analysis (PCA) was...
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Design Methodology for Small Passenger Ships On the Example of the Ferryboat Motława 2 Driven by Hybrid Propulsion System
PublicationDynamic development in practically all elds of science and engineering has not passed over shipbuilding . In last years , engineers got to their use computer soware which makes it possible to perform strength and hydrodynamic calculations as well as to visualize design projects in 3 D space [1-4]. At their disposal they have full spectrum of modern solutions associated with the use of advanced materials and technologies [5-7]....
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Propagation of Ship-Generated Noise in Shallow Sea
PublicationContamination of sea environment by noise and any energy radiated to water constitutes today a problem to which more and more attention is paid, in view, a.o., of consequences of an impact of these factors onto marine fauna. European Union has introduced a directive by which EU countries are made responsible to undertake efforts aimed at reaching a good envirenmental status of European seas by 2020. A main source of underwater...
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Safety of Bariatric Surgery in ≥ 65-Year-Old Patients During the COVID-19 Pandemic
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30-Day Morbidity and Mortality of Bariatric Surgery During the COVID-19 Pandemic: a Multinational Cohort Study of 7704 Patients from 42 Countries
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Effect of BMI on safety of bariatric surgery during the COVID-19 pandemic, procedure choice, and safety protocols – An analysis from the GENEVA Study
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30-day morbidity and mortality of sleeve gastrectomy, Roux-en-Y gastric bypass and one anastomosis gastric bypass: a propensity score-matched analysis of the GENEVA data
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Long-term hindcast simulation of sea level in the Baltic Sea
Open Research DataThe dataset contains the results of numerical modelling of sea level fluctuations over a period of 50 years (1958-2007) in the Baltic Sea. A long-term hindcast simulation was performed using a three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997). The hydrodynamic model...
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Analysis of the Water Level Variation in the Polish Part of the Vistula Lagoon (Baltic Sea) and Estimation of Water Inflow and Outflow Transport through the Strait of Baltiysk in the Years 2008–2017
PublicationThe Vistula Lagoon is located in both Poland and Russia along the southern coast of the Baltic Sea. It is connected to the Baltic Sea in the Russian part by the Strait of Baltiysk. The purpose of the paper is to identify the dominant factors underlying the water level variation mechanism at Tolkmicko in the Vistula Lagoon, revealed by a statistical analysis of the measured data and a discussion on the inflow and outflow transport...
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Influence of Added Water Mass on Ship Structure Vibration Parameters in Virtual and Real Conditions
PublicationModelling of ship structures in a virtual environment is now standard practice. Unfortunately, many engineers forget to consideri the influence of added water on the frequency values and the amplitude of natural vibrations. The article presents the effect of water damping on the frequency values of the individual natural vibration modes. The tests were carried out in two stages. First, the mentioned values were determined using...
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Atmospheric deposition in coniferous and deciduous tree stands in Poland
PublicationThe objective of this study was to assess the transformation of precipitation in terms of quantity and chemical composition following contact with the crown layer in tree stands with varied species composition, to investigate the effect of four predominant forest-forming species (pine, spruce, beech, and oak) on the amount and composition of precipitation reaching forest soils, and to determine the sources of pollution in atmospheric...
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In silico modelling for predicting the cationic hydrophobicity and cytotoxicity of ionic liquids towards the Leukemia rat cell line, Vibrio fischeri and Scenedesmus vacuolatus based on molecular interaction potentials of ions
PublicationIn this study we present prediction models for estimating in silico the cationic hydrophobicity and the cytotoxicity (log [1/EC50]) of ionic liquids (ILs) towards the Leukemia rat cell line (IPC-81), the marine bacterium Vibrio fischeri and the limnic green algae Scenedesmus vacuolatus using linear free energy relationship (LFER) descriptors computed by COSMO calculations. The LFER descriptors used for the prediction model (i.e....
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Mercury concentration and the absolute and relative sizes of the internal organs in cormorants Phalacrocorax carbo (L. 1758) from the breeding colony by the Vistula Lagoon (Poland)
PublicationThis work analyses the effect of mercury on the condition of cormorants (Phalacrocorax carbo) from an extensive breeding colony in northern Poland, the largest in Europe. A total of 55 birds (44 adults and 11 immature) were obtained. Total mercury (Hg) concentrations were measured in the liver, kidneys, breast muscles, heart, gullet (oesophagus), stomach, intestines, trachea, lungs and eyeballs. The total body mass (TBM) and empty...
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Phytoplankton communities of polar regions–Diversity depending on environmental conditions and chemical anthropopressure
PublicationThe polar regions (Arctic and Antarctic) constitute up to 14% of the biosphere and offer some of the coldest and most arid Earth's environments. Nevertheless several oxygenic phototrophs including some higher plants, mosses, lichens, various algal groups and cyanobacteria, survive that harsh climate and create the base of the trophic relationships in fragile ecosystems of polar environments. Ecosystems in polar regions are characterized...
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PROMARC Promoting Maritime Research Careers
ProjectsProject realized in Faculty of Ocean Engineering and Ship Technology according to 218590 agreement from 2008-12-18
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Long-term hindcast simulation of water temperature and salinity in the Baltic Sea
Open Research DataThe dataset contains the results of numerical modelling of water temperature and salinity over a period of 50 years (1958-2007) in the Baltic Sea. A long-term hindcast simulation was performed using a three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997). The hydrodynamic...
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Long-term hindcast simulation of currents in the Baltic Sea
Open Research DataThe dataset contains the results of numerical modelling of currents over a period of 50 years (1958-2007) in the Baltic Sea . A long-term hindcast simulation was performed using a three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997). The hydrodynamic model was coupled...