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Wyniki wyszukiwania dla: submarines
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Directional sonobuoy system for detection of submarines.
PublikacjaW artykule omówiono ogólnie hydroakustyczne metody wykrywania i lokalizacji okrętów podwodnych. Szczególną uwagę poświęcono systemowi lotniczemu wykorzystującemu sonoboje kierunkowe. Omówiono zasadę pracy takiego systemu, przedstawiono metodę detekcji i estymacji kierunku przyjścia fali akustycznej emitowanej przez okręt oraz stosowane w praktyce metody zobrazowania. Powodem podjęcia tej tematyki jest zakończenie budowy prototypu...
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The analysis of turbine propulsion systems in nuclear submarines
PublikacjaThe article systematises submarines, which are presently in service, according to their propulsion types (both conventional and nuclear), power output, and submersion depth. Contemporary types of propulsion systems installed and used in submarines are discussed. Calculations were performed for the PWR (Pressurized Water Reactor) type nuclear propulsion system and the supercritical turbine propulsion system (supercritical reactor...
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Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaAbstract: Recent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
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Particle Swarm Optimization Based Optimal Design of Six-Phase Induction Motor for Electric Propulsion of Submarines
PublikacjaRecent research reveals that multi-phase motors in electric propulsion systems are highly recommended due to their improved reliability and efficiency over traditional three phase motors. This research presented a comparison of optimal model design of a six phase squirrel cage induction motor (IM) for electric propulsion by using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). A six phase squirrel cage induction...
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Comparison of soil models in the thermodynamic analysis of a submarine pipeline buried in seabed sediments
PublikacjaThis paper deals with mathematical modelling of a seabed layer in the thermodynamic analysis of a submarine pipeline buried in seabed sediments. The existing seabed soil models: a “soil ring” and a semi-infinite soil layer are discussed in a comparative analysis of the shape factor of a surrounding soil layer. The meaning of differences in the heat transfer coefficient of a soil layer is illustrated based on a computational example...
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Combined thrust radial bearing of a submarine main shaft – Design and analysis of failure
PublikacjaThis paper presents an analysis of the combined thrust radial bearing of a submarine propulsion shaft. The lubrication system of the bearing is based on a fixed ring. The efficiency of the lubrication system depends on the shaft speed and temperature, which affects oil viscosity. In turn, the thrust bearing load also depends on the rotational speed of the shaft, because as the speed increases, the drag of the ship increases simultaneously,...
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Deep submarine groundwater discharge indicated by pore water chloride anomalies in the Gulf of Gdańsk, southern Baltic Sea
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A geophysical, geochemical and microbiological study of a newly discovered pockmark with active gas seepage and submarine groundwater discharge (MET1-BH, central Gulf of Gdańsk, southern Baltic Sea)
PublikacjaHigh-resolution bathymetric data were collected with a multi-beam echosounder in the southern part of the Baltic Sea (region MET1, Gulf of Gdańsk) revealing the presence of a 10 m deep and 50 m in diameter pockmark (MET1-BH) on the sea bottom (78.7 m). To date, no such structures have been observed to reach this size in the Baltic Sea. The salinity of the near-bottom water in the pockmark was about 2 PSU (about 31.22 mmol/l...
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Implementation of DIFAR Processing in ASW Dipping Sonar
PublikacjaThis paper presents the implementation of the signal processing algorithm used by buoy DIFAR (Directional Frequency Analysis and Recording), that is fully operational on Polish Navy anti-submarine warfare (ASW) helicopters and ships, applied to dipping sonars for detection and tracking of submarines. The development of the DSP algorithms was a part of the modernization of sonars conducted at the Gdansk University of Technology....
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Development of models for nitrogen-removal processes in subsurface flow constructed wetlands
PublikacjaThis paper summarizes recent progress in modelling approach of subsurface flow constructed wetlands (SSF CWs), focusing on nitrogen removal processes.
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Numerical Model of Surface and Quasi-Spherical Sea Noise and Its Application to Analysis of DIFAR Systems
PublikacjaVarious types of passive sonar systems are used to detect submarines. These activities are complex and demanding. Therefore, computer simulations are most often used at the design stage of these systems. For this reason, it is also necessary to simulate the acoustic ambient noise of the sea. The article proposes a new numerical model of surface and quasi-spherical sea noise and presents its statistical parameters. The results of...
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Impact of Spatial Noise Correlation on Bearing Accuracy in DIFAR Systems
PublikacjaDIFAR type underwater passive systems are one of the more commonly used tools for detecting submarines. At the design stage, which usually uses computer simulations, it is necessary to generate acoustic noise of the sea. It has been shown that correlating noise significantly reduces these errors compared to the assumption that noise is uncorrelated. In addition, bearing errors have been shown to be the same in systems with a commonly...
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Recent developments in disulfide bond formation
PublikacjaThis review summarizes the recent developments of disulfide bond formation with variety of reagents. The scope and limitation of the presented methods is discussed. The syntheses of unsymmetrical disulfides are highlighted in order to present the most versatile achievements.
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Observations of presumable groundwater seepage occurrence in Puck Bay (the Baltic Sea)
PublikacjaWe report the results of recent field measurements of seawater thermohaline structure and transparency carried out in early summer 2014 in Puck Bay. Near-bottom, less saline waters occurred almost in the entire study area. Their occurrence in the shallow part of Puck Bay was accompanied by an increase in the seawater transparency. The most likely explanation of these observations is a submarine fresh groundwater discharge.
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On the Possibility of Increasing Ship Energy Efficiency Through Improved Propulsion Control System
PublikacjaThis paper summarizes the analyses conducted to assess the impact of the ship's propulsion control system on energy efficiency in calm, manoeuvre, and sea wave conditions, where the goal of the investigation is to develop new strategies for controlling the ship's motion while considering the interactions between the hull, engine, and propeller.
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Combined Close Range Photogrammetry and Terrestrial Laser Scanning for Ship Hull Modelling
PublikacjaThe paper addresses the fields of combined close-range photogrammetry and terrestrial laser scanning in the light of ship modelling. The authors pointed out precision and measurement accuracy due to their possible complex application for ship hulls inventories. Due to prescribed vitality of every ship structure, it is crucial to prepare documentation to support the vessel processes. The presented methods are directed, combined...
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The evaluation of the vibration measurement usability of electronic indicator lemag "premet C"
PublikacjaThe measuring possibilities of modern compression and combustion pressure analyzers are extended with additional functions. One of them is parallel to the pressure measurement, the measurement of vibrations in the region of the cylinder head. The paper presents a general assessment of the vibration measurement function of the electronic indicator LEMAG "PREMET C". This feature is very rarely offered by manufacturers of these devices....
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Effect Of Resveratrol And Quercetin On Telomerase Regulation In Cancer Cells And Their Anti-Cancer Potential
PublikacjaTelomeres and telomerase are nowadays one on targets for anticancer therapy. Telomerase is expressed in ~90% of human cancer cell lines and tumor specimens, whereas its enzymatic activity is not detectable in most human somatic cells. Was found that some dietary compounds can modulate telomerase activity in cancer cells. This review summarizes the current knowledge about the effects of resveratrol and quercetin on telomerase regulation...
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Parametry uziemień przy przebiegach udarowych i wysokoczęstotliwościowych
PublikacjaW artykule skupiono się na porównaniu dwóch metod badania impedancji uziemienia odgromowego: udarowej z wysoką częstotliwościową. Zestawiono wyniki pomiarów istniejących uziemień z wynikami komputerowych obliczeń symulacyjnych przeprowadzonych w środowisku programu PSIM. Uzyskane wyniki wskazują na poprawność przyjętego toku modelowania, a uzyskane w ten sposób dane mogą być przydatne w fazie projektowania do szacowania...
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THEORETICAL ASPECTS OF PROGRESSIVE TAXATION
PublikacjaThe following article describes and discusses the theoretical aspects of taxation including its functions, mechanisms and in particular income taxes and progression system. The author analysed the literature both historical and modern to research the topic. The idea of progressive taxation has been present in modern tax system for several ages together with its positive and negative consequences. The article summarises with several...
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Activated Sludge Process Development
PublikacjaThis paper summarizes the most significant steps in the activated sludge process development and recognizes key contributors. Recognition of the roles of oxygen and living organisms was the first step (1882-1914). Ardern and Lockett (1914) named the accumulated olids "activated sludge". The process was rapidly accepted and applied in the period 1914-1930. The most dramatic changes in the activated sludge process understanding and...
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Modifications at the C(5) position of pyrimidine nucleosides
PublikacjaThis review summarizes the state of knowledge on the chemical methods of C(5)-modifications of uridine and cytidine derivatives and may serve as a useful tool for synthetic chemists to choose an appropriate reaction protocol. The synthesis of 5-substituted uracil derivatives is gaining an increasing interest because of their possible applications in medicine and pharmacy. Modifications at the C(5) position of pyrimidine nucleosides...
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Service and service decomposition model - theoretical foundation of it service management
PublikacjaThe publication contains different definitions of Service - one of the fundamental IT Service Management term. It describes types of Service attributes nad introduces so-called ''distinguish functions'' in order to propose different categories of Services. It proposes both general model of Service decomposition and practical model based on CMDB implementation limitations. In summarizes obtained results and gives some remarks about...
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THE IPV4 TO IPV6 MIGRATION OF APPLICATIONS AND SERVICE
PublikacjaThis article presents the problems related to IPv4 to IPv6 migration of applications supporting network services. It summarizes the needs of executing such migration. It shows the basic problems of automating the migration process, having defined the basic terms, i.e.: a network service, a network application. It shows a sample implementation of the automation of the migration process between IP technologies for selected network...
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Mobile Offloading Framework: Solution for Optimizing Mobile Applications Using Cloud Computing
PublikacjaNumber of mobile devices and applications is growing rapidly in recent years. Capabilities and performance of these devices can be tremendously extended with the integration of cloud computing. However, multiple challenges regarding implementation of these type of mobile applications are known, like differences in architecture, optimization and operating system support. This paper summarizes issues with mobile cloud computing and...
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Multiple jets impingement – numerical analysis by the ζ-f and hybrid VLES turbulence models
PublikacjaPresented paper summarizes the Authors findings referring to the numerical analyses of the jet impinging phenomena in the case of complex jets configurations in various applications e.g. in the heat exchangers. Multiple jets interference resulting in the cross-flow and the surface curvature are the factors which impose the need of advanced turbulence models utilization. The outcome of the research based on the ζ-f turbulence model...
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Blended Learning Model for Computer Techniques for Students of Architecture
PublikacjaAbstract: The article summarizes two-year experience of implementing hybrid formula for teaching Computer Techniques at the Faculty of Architecture at the Gdansk University of Technology. Original educational e-materials, consisting of video clips, text and graphics instructions, as well as links to online resources are embedded in the university e-learning educational platform. The author discusses technical constraints associated...
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A Review on Deactivation and Regeneration of Catalysts for Dimethyl Ether Synthesis
Publikacjahe deactivation of catalysts and their regeneration are two very important challenges that need to be addressed for many industrial processes. The most quoted reasons for the deterioration of dimethyl ether synthesis (DME) concern the sintering and the hydrothermal leaching of copper particles, their migration to acid sites, the partial formation of copper and zinc hydroxycarbonates, the formation of carbon deposits, and surface...
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Magnetic instrumentation and other applications of magnets in NOTES
PublikacjaModern surgery is developing towards a minimally invasive approach. To minimize the trauma the number of ports is either limited as in single incision laparoscopic procedures or ports are introduced through natural orifices as in nat- ural orifice translumenal endoscopic surgery (NOTES). To provide surgeons with appropriate instrumentation novel technologies are employed involving magnets. This article summarizes the theoretical...
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CONDITIONS, STREAM AND OUTLOOK FOR ECONOMIC MIGRATION FROM ASIA TO POLAND
PublikacjaThe aim of the article is to present the data about the conditions and perspectives of economic migration from Asia to Poland and data on the stream of this phenomenon in recent years based on work permission documents. The first part presents an introduction on the general migration situation to Poland in recent years and describes the theoretical approach to the aspect of migration. Then the legal conditions of migrants' work...
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The development of an underwater telephone for digital communication purposes
PublikacjaThe 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...
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Investigation of educational processes with affective computing methods
PublikacjaThis paper concerns the monitoring of educational processes with the use of new technologies for the recognition of human emotions. This paper summarizes results from three experiments, aimed at the validation of applying emotion recognition to e-learning. An analysis of the experiments’ executions provides an evaluation of the emotion elicitation methods used to monitor learners. The comparison of affect recognition algorithms...
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Magazynowanie energii elektrycznej i gospodarka wodorowa
PublikacjaW artykule dokonano przegl ą du aktualnych technologii magazynowania energii elektrycznej oraz zestawiono uzyskiwane parametry w aspekcie zastosowa ń w zasobnikach systemowych. Przedstawiono studium mo ż liwo ś ci magazynowania energii z odnawialnych ź róde ł energii (O Ź E) w zasobnikach akumulatorowych i elektrowniach szczytowo-pompowych w Polsce. Omówiono tak ż e mo ż liwo ś ci wykorzystania...
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E-technologie w edukacji i terapii dzieci z autyzmem w Polsce
PublikacjaArtykuł dotyczy możliwości wsparcia technologiami informacyjnymi edukacji i terapii dzieci z za - burzeniami rozwoju ze spektrum autyzmu. Szczególna uwaga zostanie poświęcona aplikacjom przeznaczonym na urządzenia mobilne (tablety). Artykuł podsumowuje przesłanki zastosowania tabletów w pracy z dziećmi auty - stycznymi oraz pokazuje kategorie aplikacji, jakie mogą wspierać terapię i edukację dzieci. Zostały przedstawione wyniki...
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Mercury in Living Organisms: Sources and Forms of Occurrence, Bioaccumulation, and Determination Methods
PublikacjaMercury (Hg) is a heavy metal with well-known and broadly tested toxicity. Since Hg pollution and its impacts on human health are of global concern, it has become necessary to develop analytical methodologies that will provide tools to obtain reliable analytical information about the levels of Hg in samples, which very often have a complex matrix composition. This chapter summarizes key information on Hg and its chemical forms,...
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Definition of urban regeneration projects in Russian cities
PublikacjaUrban regeneration is extremely important process for Russian cities, which faced to the challenges of post-industrial economy. In an attempt, to explain needs of urban regeneration in Russian megacities author analyzed the social and economic trends and some historic features of Russian cities development. The article identified the key areas for regeneration such as the regeneration of historic core, the regeneration of the urban...
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Agile Development of Critical Software - Can It be Justified?
PublikacjaThe paper introduces the problem of application of agile practices in critical software development projects. It summarizes the present state of research and identifies the need for having a ready-to-use model of being agile while still meeting the required assurance levels which could be particularly useful for small and medium sized safety-critical software companies. Then the objective and scope of a research aiming at delivering...
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The response of three colliding models of steel towers to seismic excitation
PublikacjaA number of past and recent observations have confirmed that collisions between adjacent, insufficiently-separated structures occurring as a result of seismic excitation (structural pounding) may result in serious damage to structural elements and can even lead to their total destruction. This paper summarises the results obtained from a shaking table experimental study which investigated structural pounding between three adjacent...
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APPLICATION OF THE HIGH FREQUENCY LINEARIZATION OF THE EAR IN PATIENTS WITH TINNITUS . Metoda linearyzacji narządu słuchu u osób cierpiących z szumami usznymi
PublikacjaThis paper summarises the problem of tinnitus, hypotheses on its causes and the treatment methods. Moreover, a hypothesis on tinnitus origins is explained, based on the mechanisms of the analog-to-digital conversion and quantization. In addition, this paper describes methods of determining the acoustic intensity and spectra of low- level ultrasonic signals, as well as impedance characteristics of an ultrasound transducer. Furthermore,...
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Improving the Survivability of Carrier Networks to Large-Scale Disasters
PublikacjaThis chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...
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Runoff Water
PublikacjaThis entry summarizes the current state of knowledge on the role of atmospheric pollutants' transport to the surface and transformations of wet deposition on contact with various surfaces. Runoff waters are one of the forms in which precipitation reaches the groundwater and surface water. They are formed when rain or melting snow washes the surfaces of roofs, highways, agricultural areas, or tree canopies. Pollutants present in...
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Multi-objective optimization of microextraction procedures
PublikacjaOptimization of extraction process requiresfinding acceptable conditions for many analytes and goodperformance in terms of process time or solvent consumption. These optimization criteria are oftencontradictory to each other, the performance of the system in given conditions is good for some criteriabut poor for others. Therefore, such problems require special assessment tools that allow to combinethese contradictory criteria into...
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Miniaturized solid-phase extraction techniques
PublikacjaMore than 80% of analysis time is spent on sample collection and sample preparation, so sample preparation is a critical part of the analytical process. Traditionally, liquid-liquid extraction was developed and employed to screen for general unknowns. However, solid-phase extraction (SPE) is becoming highly popular as an alternative, due to its simplicity and economy in terms of time and solvent. This review summarizes the current...
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Arctic Freshwater Environment Altered by the Accumulation of Commonly Determined and Potentially New POPs
PublikacjaChemical composition of Arctic freshwater ecosystems depends on several factors. They include characteristics of the surrounding landscape, its lithology, geomorphology, vegetation, and hydrological features, as well as accumulation of anthropogenic pollution. In the Arctic, the problem of environmental contamination is widespread. That is why research on lakes and river catch-ments in terms of their chemical composition has enjoyed...
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Rain Water: Atmospheric Deposition
PublikacjaWater is transferred from the atmosphere to the land surface mainly via various forms of atmospheric precipitation; however, the contribution of surface condensation/deposition (e.g., dew, hoar frost, occult precipitation) should not be neglected. Rainwater and liquid deposits (dew, hoar frost, rime) are components of the physical and geographical environment that are easily assimilated and transported. Thus, they are generally...
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Limitations of Emotion Recognition from Facial Expressions in e-Learning Context
PublikacjaThe paper concerns technology of automatic emotion recognition applied in e-learning environment. During a study of e-learning process the authors applied facial expressions observation via multiple video cameras. Preliminary analysis of the facial expressions using automatic emotion recognition tools revealed several unexpected results, including unavailability of recognition due to face coverage and significant inconsistency...
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Factors affecting the quality of bottled water
PublikacjaThe ever-increasing popularity of bottled water means that it is important to analyze not only its mineral content but also, above all,its content of possible contaminants, especially the organic ones. In this respect, bottled waters are a special case, because apartfrom organic chemical contaminants derived from the well from which they were acquired, their secondary contamination is alwayspossible, during treatment or storage...
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Soil-structure interaction effects on modal parameters of office buildings with different number of stories
PublikacjaThe paper summarizes the results of a numerical investigation designed to study the soil-structure interaction effects on modal parameters of three office buildings. The reinforced-concrete 4-storey, 8-storey, and 12-storey office buildings, each with additional two levels of embedded basements, represent low, medium, and high-rise structures, respectively. In order to conduct this research, detailed finite-element structure models...
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Polymeric porous membranes as solid support and protective material in microextraction processes: A review
PublikacjaPolymeric porous membranes have proven to be a versatile and efficient material for microextraction processes. In analytical practice, they are used both as a solid support and as a protective medium for improved sample preparation in various analytical applications. Polymeric porous membranes offer unique advantages in microextraction due to their large surface area and controllable pore size, eliminating interfering effects from...
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Pyrolysis Combined with the Dry Reforming of Waste Plastics as a Potential Method for Resource Recovery—A Review of Process Parameters and Catalysts
Publikacja: Emissions of greenhouse gases and growing amounts of waste plastic are serious environmental threats that need urgent attention. The current methods dedicated to waste plastic recycling are still insufficient and it is necessary to search for new technologies for waste plastic management. The pyrolysis-catalytic dry reforming (PCDR) of waste plastic is a promising pro-environmental way employed for the reduction of both CO2 and...