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Wyniki wyszukiwania dla: hydrogen production and combustion
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Gas Turbine Cycle with External Combustion Chamber for Prosumer and Distributed Energy Systems
PublikacjaThe use of various biofuels, usually of relatively small Lower Heating Value (LHV), affects the gas turbine efficiency. The present paper shows that applying the proposed air by-pass system of the combustor at the turbine exit causes tan increase of efficiency of the turbine cycle increased by a few points. This solution appears very promising also in combined gas/steam turbine power plants. The comparison of a turbine set operating...
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Corrosion behavior of hydrogen charged super duplex stainless steel welded joints
PublikacjaThe electrochemical behavior of the weld metal, heat-affected zone (HAZ), and base material of super duplex stainless steel (SDSS) welded joints, made with the application of flux-cored arc welding (FCAW) and submerged arc welding (SAW), were investigated with the use of metallographic examinations (optical microscopy and scanning electron microscopy), potentiodynamic polarization measurements and total hydrogen content determination...
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Effect of underwater wet welding conditions on the diffusible hydrogen content in deposited metal
PublikacjaIn the study mercury displacement method was used for determination of diffusible hydrogen amount in deposited metal obtained during underwater wet welding with covered electrodes in laboratory conditions according to a two-level full factorial design for three factors. The factors and their levels were chosen among conditions and parameters of welding in accordance with the results of own preliminary studies. A statistical analysis...
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Utilization of shale cuttings in production of lightweight aggregates
PublikacjaThe development of technologies for unconventional hydrocarbon exploration requires designing procedures to manage drilling waste that are consistent with the waste management hierarchy. In view of this, the possibility to apply shale drill cuttings as a prospective additive (replacing bentonite) to fly ash used for the production of lightweight aggregates (LWAs) was investigated. Moreover, a facile, waste-free method of LWAs production...
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Critical conditions of hydrogen-air detonation in partially confined geometry
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Factors determining selection of production planning and control system
PublikacjaThe article contains a comparative characteristics of selected systems of production planning and control, such as: MRP, kanban/JiT, DBR/TOC. The results of the performed analyses served as a basis for determining key market factors related to production planning and control functions, which determine the choice of an appropriate system.
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Hydrogen and chalcogen bonds in crystals of chalcogenadiazolecarboxylic acids – competition or cooperation?
PublikacjaThis article presents crystal structures of chalcogenadiazolecarboxylic acids bearing both a hydrogen and a chalcogen bond donor. The selected molecules varied in the size of the aromatic unit, the chalcogen atom and/or the position of the carboxyl group in the core structure. The most common synthons in their lattice are "R" _"2" ^"2" (8) self-complementary acid dimers or four-membered [Ch···N]2 rings. Supramolecular synthons...
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The role of hydrogen bonding on tuning hard-soft segments in bio-based thermoplastic poly(ether-urethane)s
PublikacjaThis work describes the preparation of bio-based thermoplastic poly(ether-urethane)s (TPU) via a prepolymer method and investigates the effect of varying the interphase hydrogen-bonding (H-bonding) on physicochemical, thermal and mechanical properties. This was achieved by varying the glycol type and molar ratio of [NCO]/[OH] groups used during the prepolymer chain extending step. The TPUs’ chemical structure was analyzed by Fourier...
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APPLICATION OF APRIORI ALGORITHM IN THE LAMINATION PROCESS IN YACHT PRODUCTION
PublikacjaThe article specifies the dependence of defects occurring in the lamination process in the production of yachts. Despite great knowledge about their genesis, they cannot be completely eliminated. Authentic data obtained through cooperation with one of the Polish yacht shipyards during the years 2013–2017 were used for the analysis. To perform a simulation, the sample size was observed in 1450 samples, consisting of 6 models of...
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Computational intelligence methods in production management
PublikacjaThis chapter presents a survey of selected computational intelligence methods used in production management. This group of methods includes, among others, approaches based on the artificial neural networks, the evolutionary algorithms, the fuzzy logic systems and the particle swarm optimization mechanisms. From the abovementioned methods particularly noteworthy are the evolutionary and the particle swarm algorithms, which are successfully...
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Correlation between partial inhibition of hydrogen evolution using thiourea and catalytic activity of AB5-type hydrogen storage alloy towards borohydride electrooxidation
PublikacjaDirect borohydride fuel cells (DBFCs) are devices which directly convert the chemical energy stored in the borohydride ion and oxidant into electrical energy as a result of redox reactions. Unfortunately, a significant amount of fuel is lost as a result of the undesirable hydrolysis reaction. The selection of an efficient borohydride hydrolysis inhibitor requires detailed knowledge regarding the interaction mechanism between the...
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Biomass in biogas production: Pretreatment and codigestion
PublikacjaGlobally, there is increasing awareness that the implementation of ‘waste to energy’ technology is one of the best means to achieve sustainable energy development. The most popular approach is the conversion of organic-rich compounds into clean and renewable products by anaerobic digestion (AD). Biogas can be produced from agricultural residues, municipal/industrial biowastes, and sustainable biomass, especially materials that...
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Integration of natural and artificial intelligence in production systems
PublikacjaIntegration processes play an increasingly important role in modern economy, and seriously co-decide about the effectiveness of the company. Integration phase occurs in the system life cycle by preceding the final stages of its implementation and activation. In turn, used in software engineering (SE) iteration-evolutionary models, such as spiral model make that the integration activities can occur in varying degrees in all phases...
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Investigation into the Effect of Spinel Pigments on the Photostability and Combustion Properties of Ethylene-Norbornene Copolymer
PublikacjaMulticolor ethylene-norbornene (EN) composites filled with three different spinel pigments (Cobalt Green-PG50, Zinc Iron Yellow-PY 119, Praseodym Yellow-PY159) were prepared by melt mixing and characterized in terms of their stability under destructive environmental conditions. The EN films were subjected to accelerated aging by ultraviolet (UV) photooxidation for 300 h, 600 h, or 900 h. The mechanical performance of the EN composites...
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Preliminary investigations of effect of conditions of FCAW process on diffusible hydrogen content in deposited metal
PublikacjaOne of the types of hydrogen degradation of steel welded joints is cold cracking. The direct cause of the formation of cold cracks is simultaneous presence of hydrogen, residual stresses and brittle structure. The way of preventing the occurring of degradation is to eliminate at least one of these factors. Practice has shown that the best solution is to control the amount of hydrogen in deposited metal. In this paper the state...
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Application of industrial waste as a carbon source for biosurfactants production
PublikacjaBiosurfactants are natural surfactants produced by variety of microorganisms. They are very prospective product due to good biodegradability, low toxicity, good physicochemical properties and high efficiency in many applications. Moreover, they are efficient in wide range of pH, temperatures and salinity. However, the production of biosurfactants is very expensive due to high purification cost. This cost can be minimized by application...
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Techno-economic assessment of cooperation of hybrid renewable energy sources with hydrogen storage
PublikacjaThe paper presents a technical and economic analysis of the power supply for a model industrial facility with the use of the most promising renewable energy sources (RES), supported by a hydrogen energy storage. This scenario was compared with the variants of supplying the facility directly from the grid and from RES without energy storage. A strategy was proposed for powering the plant aimed at maximising self-consumption of self-generated...
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Shape-controllable synthesis of GdVO4 photocatalysts and their tunable properties in photocatalytic hydrogen generation
PublikacjaNovel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light...
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The effect of pre-hydrogen charging on corrosion behaviour of superduplex stainless steel welded joints
PublikacjaThe paper presents results of research undertaken to determine the influence of hydrogen on passivity and corrosion resistance of 2507 super duplex stainless steel welded joints. Butt welded joints were made with low heat input using flux corded arc welding (FCAW) method. Coupons of 5.0 x 5.0 mm were cut from the welded joints containing weld metal (WM), heat affected zone (HAZ) and parent metal (PM). Hydrogen was introduced...
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Cooperative control in production and logistics
PublikacjaClassical applications of control engineering and information and communication technology (ICT) in production and logistics are often done in a rigid, centralized and hierarchical way. These inflexible approaches are typically not able to cope with the complexities of the manufacturing environment, such as the instabilities, uncertainties and abrupt changes caused by internal and external disturbances, or a large number and variety...
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Evaluation of Batch Production Processes Based on Seven Criterions
PublikacjaTo answer growing demand on products adapted to clients’ individual needs, it is required to develop new ways of measurement and rating for batch production processes. The researchers developed method which allows synthetic and complex evaluation, as well as improvement of these processes. Case study with participating observation, non-participating observation, interviews, and the analysis of historical data was conducted in order...
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Seaweed utilization issues in biogas production
PublikacjaMacroalgae can be seen as a renewable feedstock for the production of biofuels in many coastal areas around the World and especially in Baltic Sea region where the eutrophication is particularly troublesome. The investigation of anaerobic digestion technologies for extracting inexhaustible bioenergy from seaweed was conducted in many research institutions mainly in laboratory scale. Although seaweeds seem to have a great potential...
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Synthesis and hydrogen evolving catalysis of a panchromatic photochemical molecular device
PublikacjaA dinuclear hydrogen evolution photocatalyst [(tbbpy)2Os(tpphz)PtI2](PF6)2 (tbbpy = 4,4′-tert-butyl-2,2′-bipyridine; tpphz = tetrapyrido[3,2-a:2′,3′-c:2′′,3′′-h:2′′′,3′′′-j]phenazine) is synthesized in order to make use of the broader range of visible light absorption mitigated by the osmium center. In a first step, the activity of the complex for hydrogen evolution is investigated by evaluating the role of different electron donors...
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The influence of robotization on the reliability of the production process in the bakery industry
PublikacjaThis article presents a new concept of technological system reliability based on the analysis of the relationship of associations of elements of energy streams, matter, information, time and finance. The method of stream specification and the method of determining the reliability values of significant and supporting relationships are given. Relevant relationships between elements of system streams were defined as having one-time...
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Graphene Production and Biomedical Applications: A Review
PublikacjaGraphene is a two-dimensional nanomaterial composed of carbon atoms with sp2 hybrid orbitals. Both graphene and graphene-based composite have gained broad interest among researchers because of their outstanding physiochemical, mechanical, and biological properties. Graphene production techniques are divided into top-down and bottom-up synthesis methods, of which chemical vapor deposition (CVD) is the most popular. The biomedical...
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Carburization Behavior of High-Grade Pellets After Direct Reduction in Pure Hydrogen
PublikacjaCarburization is a critical aspect in the iron and steel industry as it significantly affects the mechanical and chemical properties of the final product. This study provides a comprehensive analysis of the carburization potential of high-grade quality iron ore pellets after direct reduction in pure hydrogen. The results show that the porosity of the pellets has a significant impact on the efficiency and success of the direct reduction...
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Ecological trends in machining as a key factor in sustainable production – A review
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Entropy Production Associated with Aggregation into Granules in a Subdiffusive Environment
PublikacjaWe study the entropy production that is associated with the growing or shrinking of a small granule in, for instance, a colloidal suspension or in an aggregating polymer chain. A granule will fluctuate in size when the energy of binding is comparable to k_{B}T, which is the “quantum” of Brownian energy. Especially for polymers, the conformational energy landscape is often rough and has been commonly modeled as being self-similar...
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Import Intensity of Production, Tasks and Wages: Microlevel Evidence for Poland.
PublikacjaObjective: This article relates to recent literature on labour market consequences of production fragmentation within Global Value Chains, analysed in the presence of workers’ heterogeneity and differences in the task content of jobs. The main aim is to assess if there is a relationship between wages of Polish workers and the degree of Polish production dependence on imported inputs. Research Design & Methods: Using microdata from...
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Influence of High Temperature Oxidation on Hydrogen Absorption and Degradation of Zircaloy-2 and Zr 700 Alloys
PublikacjaThe present research was aimed at determining the effects of the oxide layers on hydrogen absorption, microstructure and mechanical properties of the Zircaloy- 2 and Zr 702 alloys. The oxidation was made at 350 °C, 700 °C and 900 °C for 10 to 30 min in laboratory air, followed by hydrogen cathodic charging for 72 h and annealing at 400 °C for 4 h. The slow strain rate tests were carried out on oxidized, charged and annealed specimens. The...
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An integral-differential method for impedance determination of the hydrogen oxidation process in the presence of carbon monoxide in the proton exchange membrane fuel cell
PublikacjaThe impedance of a proton exchange membrane fuel cell powered by hydrogen contaminated with carbon monoxide, ranging from 150 to 300 ppb, is measured and discussed. The tested range of CO concentration complied with the fuel standard specified in the ISO standards. Studies of influence of CO contamination on operation of PEMFC are crucial for further development and commercialization of fuel cells for automotive applications. Based...
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Analysis of balancing of six-cylinder in-line two-stroke internal combustion engines = Analiza wyrównoważenia silników rzędowych dwusuwowych sześciocylindrowych
PublikacjaW pracy wyprowadzono proste zależności opisujące przebieg momentu od sił bezwładności pierwszego i drugiego rzędu dla wszystkich 60 wariantów wałów korbowych w silniku 6-cylindrowym 2-suwowym rzędowym. Dokonano analizy i porównania poszczególnych wariantów z punktu widzenia momentów wypadkowych od sił bezwładności pierwszego i drugiego rzędu. Porównania dokonano dla dwóch wartości parametru mechanizmu korbowego 0,3 i 0,5.
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Hydrogen fuel cell power supply for hybrid elelectric multiple unit train
PublikacjaIn European countries, electrified routes amount for 40% to 65% of the total railway networks length. Some of those routes are only partially electrified, and construction of a catenary network might not be viable on all routes. Consequently, operators run diesel trains under catenary or require both an electric and diesel vehicle, increasing costs of operation. Dual-mode vehicles exist, but they are mostly equipped with diesel...
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Systematic investigation on combustion characteristics and emission-reduction mechanism of potentially toxic elements in biomass- and biochar-coal co-combustion systems
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Impacts of Using Exhaust Gas Recirculation and Various Amount of Dimethyl Ether Premixed Ratios on Combustion and Emissions on a Dual-Fuel Compression Ignition Engine
PublikacjaIn the presented research, the authors dealt with the specific properties of the combustion process of dimethyl ether (DME) in a combustion car (Volkswagen Golf IV) engine AJM 1.9 TDI PDE made by Volkswagen factory. Dimethyl ether is an alternative fuel produced most often from natural gas, which can be used in compression ignition engines as a single fuel or co-burned with diesel oil. This work describes the impacts of using exhaust...
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Two-dimensional hydrogen-like atom in a weak magnetic field
PublikacjaWe consider a non-relativistic two-dimensional (2D) hydrogen-like atom in a weak, static, uniform magnetic field perpendicular to the atomic plane. Within the framework of the Rayleigh-Schr¨odinger perturbation theory, using the Sturmian expansion of the generalized radial Coulomb Green function, we derive explicit analytical expressions for corrections to an arbitrary planar hydrogenic bound-state energy level, up to the fourth...
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Reliability of production machines in the bakery industry – theoretical and practical issues
PublikacjaThe aim of the article is to present probabilistic models, which were then used to analyze the reliability of production machines in the baking industry. The author conducted research in the period from January 2, 2016 to December 31, 2018 regarding the measurement of reliability of a traditional production system based on a probabilistic concept. Due to the limited scope of the article, reliability calculations for a set of thermo-oil...
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Hydrogen assisted cracking of 2205 duplex stainless steel in synthetic sea water
PublikacjaThe cracking behavior of 2205 duplex stainless steels (DSSs) in synthetic sea water under cathodic polarization condition was investigated. (SSRT) method was employed in aim to evaluate the susceptibility to hydrogen assisted cracking. The results showed that the reduction in the uniform elongation (UEL) and the reduction of area (RA) varied with the applied cathodic current density. Significant reductions in ductility were found,...
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Effect of shielded electrode wet welding conditions on diffusible hydrogen content in deposited metal
PublikacjaWet welding is the most popular method of joining in water enviroment. During underwater welding, the weldability of steel is limited by the higher cooling rates and hydrogen content in weld metal. Article presents results of preliminary tests on the effects of wet welding conditions on diffusible hydrogen amount. Seven parameters were optimized using a Plackett-Burman plan to get the most relevant variables. These parameters were:...
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The Effect of Oxygenated Diesel-N-Butanol Fuel Blends on Combustion, Performance, and Exhaust Emissions of a Turbocharged CRDI Diesel Engine
PublikacjaThe article deals with the effects made by using various n-butanol-diesel fuel blends on the combustion history, engine performance and exhaust emissions of a turbocharged four-stroke, four-cylinder, CRDI 1154HP (85 kW) diesel engine. At first, load characteristics were taken when running an engine with normal diesel fuel (DF) to have ‘baseline’ parameters at the two ranges of speed of 1800 and 2500 rpm. Four a fossil diesel (class...
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A model of fuel combustion process in the marine reciprocating engine work space taking into account load and wear of crankshaft-piston assembly and the theory of semi-Markov processes
PublikacjaThe ar ticle analyses the operation of reciprocal internal combu stion engines, with mar ine engines u sed a s an example. The analysis takes into account types of energy conversion in the work spaces (cylinders) of these engines, loads of their crankshaft-piston assemblies, and types of fuel combustion which can take place in these spaces during engine operation. It is highlighted that the analysed time-dependent loads of marine...
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Exergy analysis of a negative CO2 emission gas power plant based on water oxy-combustion of syngas from sewage sludge gasification and CCS
PublikacjaA power cycle with water-injected oxy-combustion (water cycle) is investigated by exergy analysis. It is fueled with syngas (aka. producer gas) from gasification of sewage sludge. The cycle is equipped with a spray-ejector condenser (SEC). CO2 is separated and compressed for transportation and storage. The net delivered electric power is 31% of the fuel exergy. The task efficiency is 39% when the flue gas bleed to gasification...
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Supramolecular Synthesis Based on a Combination of Se···N Secondary Bonding Interactions with Hydrogen and Halogen Bonds
PublikacjaExamination of the solid state structures of 2,1,3-benzoselenadiazole complexes with hydrogen or halogen bond donors has demonstrated that the 2,1,3-benzoselenadiazole molecules preferably form centrosymmetric dimers with use of [Se–N]2 supramolecular synthon, whereas the two remaining nitrogen atoms not involved in the [Se–N]2 supramolecular interactions can act as acceptors of hydrogen or halogen bonds. Cocrystallization of selenadiazoles...
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Effect of the welding environment and storage time of electrodes on the diffusible hydrogen content in deposited metal
PublikacjaIn the study the glycerin displacement method was used for determination of diffusible hydrogen content in deposited metal. Specimens were welded in the air and in the water with covered rutile electrodes. The first part of the specimens was made immediately after opening the package of the electrodes. The electrodes were then stored in opened packages in laboratory conditions that allowed for contact with the air for three years....
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Effect of wet Hydrogen Sulfide on Carbon Steels Degradation in Refinery Based on Case Study
PublikacjaMaterial degradation caused by wet hydrogen sulfide (Wet H2S) is one of the major issues in refineries. Carbon steel is the main construction material used in refineries and is subjected not only to thickness loss but the hydrogen is the major concern. H2S leads to high atomic hydrogen penetration in steel which causes degradation in the form of blistering and/or cracking (HIC/SOHIC) and stress cracking in the area of welds and...
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Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production
PublikacjaThe aim of this review is to present the recent developments in heat pipe production, which respond to the current technical problems related to the wide implementation of this technology. A novel approach in HP manufacturing is to utilise hi-tech additive manufacturing techniques where the most complicated geometries are fabricated layer-by-layer directly from a digital file. This technology might be a solution to various challenges...
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Investigation of the Combustion Processes in the Gas Turbine Module of an FPSO Operating on Associated Gas Conversion Products
PublikacjaIn this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight...
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Similarities and differences in the production of renewable energy in Central and Eastern Europe countries
PublikacjaResearch background: In the era of climate change, environmental degradation, but also growing pub-lic awareness, there is a need to look for new ecological energy sources. This condition can be met by renewable energy sources (RES). The EU seeks to have a 32% share of its gross final energy consumption from renewable sources by 2030. While the EU as a whole is on course to meet its...
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2-Methoxyestradiol and Hydrogen Peroxide as Promising Biomarkers in Parkinson’s Disease
PublikacjaEstrogens function in numerous physiological processes including controlling brain cell growth and differentiation. 2-Meth- oxestradiol (2-ME2), a 17β-estradiol (E2) metabolite, is known for its anticancer effects as observed both in vivo and in vitro. 2-ME2 affects all actively dividing cells, including neurons. The study aimed to determine whether 2-ME2 is a potentially cancer-protective or rather neurodegenerative agent in a...
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Production fragmentation and employment. Country-industry level analysis based on WIOD 2016
PublikacjaThe aim of this research is to reanalyse the possible impact of production fragmentation on employment using the newest world input-output database (WIOD) release (2016) and recently proposed by Timmer, Los, Stehrer and de Vries measure of production fragmentation which traces the imports needed in all stages of production. This study is provided on country-industry level for 56 industries and 41 countries for the years 2000–2014....