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Evaluation of Green Sample Preparation Techniques for Organic Compounds
PublikacjaNowadays, Green Analytical Chemistry (GAC) idea is of high importance, with impact on the rapid growth in the sample preparation area with special emphasis on sample preparation simplification, miniaturization and automation. Due to the fact that GAC is of high importance today, this study is focused on the evaluation of green sample preparation techniques for organic compounds. It is well known that sample preparation is considered...
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Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant
PublikacjaOne promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle...
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The impact of initial and boundary conditions on severe weather event simulations using a high-resolution WRF model. Case study of the derecho event in Poland on 11 August 2017
PublikacjaPrecise simulations of severe weather events are a challenge in the era of changing climate. By performing simulations correctly and accurately, these phenomena can be studied and better understood. In this paper, we have verified how different initial and boundary conditions affect the quality of simulations performed using the Weather Research and Forecasting Model (WRF). For our analysis, we chose...
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Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
PublikacjaReduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion...
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A facile approach to fabricate load-bearing porous polymer scaffolds for bone tissue engineering
PublikacjaBiodegradable porous scaffolds with oriented interconnected pores and high mechanical are load-bearing biomaterials for bone tissue engineering. Herein, we report a simple, non-toxic, and cost-effective method to fabricate high-strength porous biodegradable scaffolds, composed of a polymer matrix of polycaprolactone (PCL) and water-soluble poly (ethylene oxide) (PEO) as a sacrificial material by integrating annealing treatment,...
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A novel approach for processing CaAlSiON glass-ceramics by spark plasma sintering: Mechanical and electrical properties
PublikacjaLithium containing glassy materials can be used as solid electrolytes or electrode materials for lithium-ion batteries due to their high energy density. Conventional melt-quenched Ca11Al14Si16O49N10 glass powder containing 24 e/o N, doped with Li-ions (1, 3, and 6 wt. %) and sintered by spark plasma sintering technique (SPS) was studied. The benefits of using SPS to produce glass-ceramics are rapid heating rates compared to conventional...
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The effects of the IM1-12Br ionic liquid and the oxytetracycline mixture on selected marine and brackish microorganisms
PublikacjaThe number of applications and commercialized processes utilizing ionic liquids has been increasing, and it is anticipated that this trend will persist and even intensify in the future. Ionic liquids possess desirable characteristics, such as low vapor pressure, good water solubility, amphiphilicity, and stability. Nevertheless, these properties can influence their environmental behavior, resulting in resistance to biotic and abiotic...
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Deodorization of model biogas by means of novel non-ionic deep eutectic solvent
PublikacjaThe paper presents new non-ionic deep eutectic solvent (DES) composed of natural and non-toxic components i.e. guaiacol, camphor and levulinic acid in 1:1:3 molar ratio as a promising absorbent for removal of selected volatile organic compounds (VOCs) including dichloromethane, toluene, hexamethyldisiloxane and propionaldehyde from model biogas. The affi nity of DES for VOCs was determined as vapour-liquid coeffi cients and the...
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Inter Applied Chemistry Programme 5 Intorduction to hazard assessment of chemicals Marta Markiewicz
Kursy OnlineInter Applied Chemistry Programme 5 Intorduction to hazard assessment of chemicals Marta Markiewicz Marta Markiewicz obtained a Master’s degree in Biotechnological Engineering in 2007 from Koszalin University of Technology with the thesis focusing on recovery of native proteins from industrial waste streams using preparative ion-exchange chromatography. Subsequently she obtained a PhD in Technical Science (2012) from Gdańsk...
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Soxhlet Extraction and New Developments Such as Soxtec in: Comprehansive Sampling and Sample Preparation
PublikacjaSoxhlet extraction is one of the most popular techniques for extraction of analytes from solid materials. Since its discovery in 1879, the standard Soxhlet technique has been routinely applied in almost every analytical laboratory. Up to this day, Soxhlet extraction technique remains a standard technique to which the performance of modern extraction techniques is compared.Over the years, an intensive research on different modifications...
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Systematic Water Uptake Energetics of Yttrium-Doped Barium Zirconate—A High Resolution Thermochemical Study
PublikacjaA combination of surface area analyzer and microcalorimetry was employed to investigate the in situ water uptake energetics and the mechanism of proton incorporation in yttrium-doped barium zirconate in the temperature range 200–400 °C. The BaZr1–xYxO3 solid solutions are made with variable yttrium content (x = 10, 20, and 30 mol %) by a controlled oxidant-peroxo synthesis method. The water uptake increases as the partial pressure...
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Simulations of hydro-fracking in rock mass at meso-scale using fully coupled DEM/CFD approach
PublikacjaThe paper deals with two-dimensional (2D) numerical modelling of hydro-fracking (hydraulic fracturing) in rocks at the meso-scale. A numerical model was developed to characterize the properties of fluid-driven fractures in rocks by combining the discrete element method (DEM) with computational fluid dynamics (CFD). The mechanical behaviour of the rock matrix was simulated with DEM and the behaviour of the fracturing fluid flow...
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The structure of vanadate glasses containing BaTiO3.
Dane BadawczeThe structure of vanadate glasses doped with BaTiO3 was measured by SEM technique. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on a preheated...
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Chemical composition of tellurium oxides thin films deposited by magnetron sputtering method
Dane BadawczeThin films were prepared by radio frequency reactive magnetron sputtering technique. Metallic Te target was sputtered for about 45 min in argon-oxygen atmosphere what resulted in 300 nm film thickness deposition. The pressure in the chamber was below 0.2 Pa and substrate was heated at 200 °C. The distance between sputtered target and the Corning 1737...
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Lanthanum investigations in ceramics annealed in a dry and wet atmosphere
Dane BadawczeCeramics based on Barium, Lanthanum, Gadolinium and Cobaltium were produced by standard solid state reaction from oxides and carbonate powders. After sintring, samples were annealed for 2 hours or 72 hours at 300 Celsius degree in a both: wet and dry atmosphere. Results of annealing on a chemical composition and valence state of lanthanum were observed...
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Complex multidisciplinary optimization of turbine blading systems
PublikacjaThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...
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Influence of PWHT Parameters on the Mechanical Properties and Microstructural Behavior of Multi-Pass GTAW Joints of P92 Steel
PublikacjaThe 9% Cr steels were developed for ultra-supercritical (USC) power plants to meet the requirements of high operating temperature and pressure. These steels are produced to operate at high temperatures where impact toughness is not a concern; however, it becomes important for the welded joints to have good impact toughness at room temperature for manufacturing. The present work investigates the effect of the post-weld heat treatment...
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Structure redetermination, transport and thermal properties of the YNi3Al9 compound
PublikacjaSingle crystals of completely ordered variant of the YNi3Al9 compound were grown by self-flux method with excess of aluminum. The crystal structure of the title compound was redetermined from single crystal X-ray diffraction data. The structure adopts ErNi3Al9 type, space group R32, parameters of the unit cell a = 7.2838(2) Å, c = 27.4004(8) Å. The growth of relatively large single crystals of the YNi3Al9 compound, having completely...
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Thermal dewetting as a method of surface modification of the gold thin films for surface plasmon resonance based sensor applications
PublikacjaHere, we report a quick and simple approach with low, optimized production costs to obtain surface plasmon resonance (SPR) based sensors fabricated through a time- and resource-effective method based on thermal dewetting of thin Au films. From the applicative point of view, the method of detection presented here should be easier to implement, since light transmission measurements seem to be much less challenging than light refractive...
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D.C. electrical measurements of Bi2VO5.5 ceramic measured at high temperature region
Dane BadawczeD.C. electrical properties of Bi2VO5.5 ceramic was measured.
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Potentiometric Oxygen Sensor with Solid State Reference Electrode
PublikacjaThe concentration or the partial pressure of oxygen in an environment can be determined using different measuring principles. For high temperature measurements of oxygen, ceramic-based sensors are the most practical. They are simple in construction, exploration and maintenance. A typical oxygen potentiometric sensor consists of an oxygen ion conducting solid electrolyte and two electrodes deposited...
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Applicability of arrays of microjets heat transfer correlations to design compact heat exchangers
PublikacjaThe article presents experimental studies on a compact heat exchanger with heat transfer intensification by means of impinging microjets. The pursuit to provide high performance of heat exchangers is a response to the demand both in economics and in the universal tendency to miniaturization of industrial equipment. This paper presents the design and tests of a prototype, microjet heat exchanger. The modular design of the heat exchanger...
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THE THERMODYNAMIC ANALYSIS OF THE SZEWALSKI HIERARCHIC VAPOUR CYCLE COOPERATED WITH THE SYSTEM OF HEAT RECOVERY
PublikacjaIn this paper, thermodynamic analysis of the Szewalski hierarchic vapour cycle cooperated with the system of heat recovery from exhaust gases are presented. According to that purpose, the CFM (Computation Flow Mechanics [1,3]) approach has correctly been used. The whole system consists of the first traditional steam cycle, the second organic Rankine cycle (ORC) and system of heat recovery with use of water with temperature 90...
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Structure and paramagnetism in weakly correlated Y8Co5
PublikacjaWe report the basic physical properties of monoclinic Y8Co5 determined by means of magnetic susceptibility, electrical resistivity, and specific heat measurements. The crystal structure of Y8Co5 is monoclinic (P21/c) with lattice parameters a = 7.0582(6) Å, b = 7.2894(6) Å, c = 24.2234(19) Å, and β = 102.112(6)° as refined by using synchrotron powder x-ray diffraction data. The compound shows temperature independent paramagnetism...
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Three-dimensional characterization of porosity in iron ore pellets: A comprehensive study
PublikacjaThis paper presents a comprehensive study on the production and reduction of high-quality iron ore pellets characterized by a basicity index nearing 0.5 and diameters ranging from 1 to 2 cm. The reduction process was carried out in a hydrogen atmosphere at temperatures spanning 800–1000 ◦ C and a pressure of 8 bar. Initial f indings revealed substantial variations in pellet density and compressive strength, attributed to their...
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Broadening the scope of measurement and analysis of vibrations of an organ pipe employing intensity probe, simulations, and highspeed camera
PublikacjaThis paper shows an integrated approach to measure, analyze, and model phenomena occurring in an organ pipe driven by pressurized air. The aim of this paper is two-fold, i.e., to measure the pressure signal and the intensity field around the mouth by means of an intensity probe and to visualize and observe the motion of the air jet, which represents the excitation mechanism of the system. This is realized through two techniques,...
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Surface engineering of graphene oxide membranes for selective separation of perfluorooctanoic acids
PublikacjaPerfluoroalkyl compounds (PFCs) are environmental toxicants and their widespread detection and accumulation in the environment can be detrimental to the ecosystem. In this study, surface charge of GO membranes was engineered to enhance selectivity of graphene oxide (GO) membranes and for the removal of perfluorooctanoic acid (PFOA ∼400 Da) in real concentration ranges in wastewater streams. The structure and physicochemical properties...
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Recent Progress on Hydrogen Storage and Production Using Chemical Hydrogen Carriers
PublikacjaDepleting fossil fuel resources and anthropogenic climate changes are the reasons for the intensive development of new, sustainable technologies based on renewable energy sources. One of the most promising strategies is the utilization of hydrogen as an energy vector. However, the limiting issue for large-scale commercialization of hydrogen technologies is a safe, efficient, and economical method of gas storage. In industrial practice,...
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Novel Biodegradable Potato Starch-based Compositions as Candidates in Packaging Industry, Safe for Marine Environment
PublikacjaAbout 70 % of our planet’s surface is covered by seas and oceans to which even 10 million tons of waste go every year. It makes these places the largest global landfills, containing up to 90 % of plastic waste. In this article we present the results of research on novel starch-based compositions expected to be more safe for the marine environment. For these purpose biopolymers such as, thermoplastic starch (TPS), polylactide (PLA)...
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A Pilot Study on Machining Difficult-to-Cut Materials with the Use of Tools Fabricated by SLS Technology
PublikacjaThe growing use of contemporary materials in various industrial sectors, such as aerospace, automotive, as well as the oil and gas industry, requires appropriate machining methods and tools. Currently, apart from the necessity to obtain high-dimensional and shape accuracy, the efficiency and economic aspects of the selected manufacturing process are equally important, especially when difficult-to-cut materials, such as hard and...
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Organic Supercritical Thermodynamic Cycles with Isothermal Turbine
PublikacjaOrganic Rankine cycles (ORC) are quite popular, but the overall efficiencies of these plants are rather very low. Numerous studies have been conducted in many scientific centers and research centers to improve the efficiency of such cycles. The research concerns both the modification of the cycle and the increase in the parameters of the medium at the inlet to the turbine. However, the efficiency of even these modified cycles rarely...
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The luminescence study of LiGa5(1−x)O8:5xCr3+ coumpounds
Dane BadawczeInfrared luminescent materials have evoked much attention from chemists and material scientists. Although substantial progress is made in materials design, the luminescent mechanism remains ambiguous in the complex structures, presenting major barriers to developing novel infrared luminescent materials. Herein, this study aims to deliberate a complete...
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Ongoing Progress on Pervaporation Membranes for Ethanol Separation
PublikacjaEthanol, a versatile chemical extensively employed in several fields, including fuel production, food and beverage, pharmaceutical and healthcare industries, and chemical manufacturing, continues to witness expanding applications. Consequently, there is an ongoing need for cost-effective and environmentally friendly purification technologies for this organic compound in both diluted (ethanol-water–) and concentrated solutions (water-ethanol–)....
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An experimental assessment on a diesel engine powered by blends of waste-plastic-derived pyrolysis oil with diesel
PublikacjaThe utilization of plastic solid wastes for sustainable energy production is a crucial aspect of the circular economy. This study focuses on pyrolysis as an effective method to convert this feedstock into renewable drop-in fuel. To achieve this, it is essential to have a comprehensive understanding of feedstock composition, pyrolysis process parameters, and the physicochemical characteristics of the resulting fuel, all correlated...
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Effect of asymmetric fluid flow distribution on flow boiling in a microchannel heat sink – An experimental investigation
PublikacjaFlow boiling in microchannels is emerging as an exclusive cooling solution for miniaturized high-power electronic devices alongside having other high heat flux applications. Size miniaturization at microscale strangely increases heat transfer performance as well as flow boiling instabilities. Many flow boiling instabilities are interrelated and result from imperfect hydrodynamic conditions. One of such problems is flow maldistribution among...
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The structure of vanadate glass-ceramics containing BaTiO3.
Dane BadawczeThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by SEM technique. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on...
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INNOVATIVE RUN FLAT SYSTEMS
PublikacjaOne of the most essential threats to the mobility of wheeled vehicles is their relatively high sensitivity to tire damage. Tires can be damaged as a result at vehicle-targeting fire, after running on a mine or an improvised charge. The purpose of the article is to analyze the current technical solutions in wheeled vehicle tires, allowing for the unobstructed use of the vehicle despite the damage of one or several tires (RUN FLAT...
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Entire fracture surface topography parameters for fatigue life assessment of 10H2M steel
PublikacjaIn this paper, the entire fracture surface approach was used to assess an effect of 280,000 h of exploitation under internal pressure of 2.9 MPa and high temperature of 540 °C on the fatigue response of 10H2M (10CrMo9–10) power engineering steel. The mechanical testing was carried out on the hourglass specimens produced from the as-received, unused pipeline and the same material after long-time exploitation. The uniaxial tensile...
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High-speed multi-stage gas-steam turbine with flow bleeding in a novel thermodynamic cycle for decarbonizing power generation
PublikacjaIn the global pursuit of sustainable energy and reduced carbon footprints, advances in power generation techniques play a crucial role, not only in meeting the ever-increasing energy demands but also in ensuring that environmental standards are maintained and that the health of our planet is prioritized for future generations. In the ongoing quest for sustainable energy solutions, novel high-speed multi-stage gas-steam turbine...
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Impact of abiotic stressors on nutrient removal and rhizomicrobiome composition in floating treatment wetland with Equisetum hyemale
PublikacjaFloating treatment wetlands (FTW) are receiving growing interest as a phyto-technology. However, there are significant research gaps regarding the actual role of plant species and plant-microbiome interactions. In this study, the nutrient uptake of Equisetum hyemale was examined in FTW microcosms under the influence of abiotic stressors: As (3 mg/L) and Pb (3 mg/L) as well as Cl− (300 and 800 mg/L) in reference to a control during...
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Numerical analysis of high temperature minichannels heat exchanger performance
PublikacjaNowadays, the most difficult technological challenge in energy sector is connected with the gas micro-CHP units, dedicated to the distributed power generation. They are expected to be of high efficiency and at the same time of compact in size. Regarding the first reason, significant increase in microturbine efficiency can only be achieved by increase in the engine operating temperature. Therefore, one of the critical elements in...
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The influence oil additives on spread cracks in silicon nitride
PublikacjaThe paper presents an experimental study of the influence of oil additives (Cl, S, P, cerium dioxide (CeO2)) on spread cracks in silicon nitride. The additives Cl, S, P are bound in molecules in liquid form soluble in the base oil. The CeO2 is purely in powder form in suspension. The use of CeO2 powder was made based on the good results of polishing of silicon nitride. A ceramic angular contact ball bearing was modelled using a...
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Injectable bone cement based on magnesium potassium phosphate and cross-linked alginate hydrogel designed for minimally invasive orthopedic procedures
PublikacjaBone cement based on magnesium phosphate has extremely favorable properties for its application as a bioactive bone substitute. However, further improvement is still expected due to difficult injectability and high brittleness. This paper reported the preparation of novel biocomposite cement, classified as dual-setting, obtained through ceramic hydration reaction and polymer cross-linking. Cement was composed of magnesium potassium...
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Unraveling Luminescent Energy Transfer Pathways: Futuristic Approach of Miniature Shortwave Infrared Light-Emitting Diode Design
Dane BadawczePhosphor-converted shortwave infrared phosphor light-emitting diodes (pc-SWIR LEDs, 900–1700 nm) are promising next-generation portable light sources for spectroscopy, security, optical communication, and medical applications. A typical design strategy involves energy transfer from Cr3+ to Ni2+, and thus, energy transfer from Cr3+–Cr3+ pairs to Ni2+...
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The application of magnetic fluids in sealing nodes designed for operation in difficult conditions and in machines used in sea environment
PublikacjaPresented in article MF seals are being researched for sea technology purposes due to their excellent tightness and low resistance of motion. These features are most valuable for ring propellers and ship's main propeller shaft. There are more reasons why technologists payf significant attention for various MFseals applications in their difficult operating conditions. For instance, an advanced pumping systems are designed with contactless...
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The application of magnetic fluids in sealing nodes designed for operation in difficult conditions and in machines used in sea environment
PublikacjaPresented in article MF seals are being researched for sea technology purposes due to their excellenttightness and low resistance of motion. These features are most valuable for ring propellers and ship'smain propeller shaft. There are more reasons why technologists payf significant attention for various MFseals applications in their difficult operating conditions. For instance, an advanced pumping systemsare designed with contactless...
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Exergy analysis of the Szewalski cycle with a waste heat recovery system
PublikacjaThe conversion of a waste heat energy to electricity is now becoming one of the key points to improve the energy efficiency in a process engineering. However, large losses of a low-temperature thermal energy are also present in power engineering. One of such sources of waste heat in power plants are exhaust gases at the outlet of boilers. Through usage of a waste heat regeneration system it is possible to attain a heat rate of approximately...
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Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness
PublikacjaThe shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil,centrifugal force is acting on the moving fluid due to the curvature of thetube results in the development. It has been long recognized that the...
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Weldability of pipe grade polyethylenes as realized from thermal and mechanical properties assessments
PublikacjaSince polyethylene (PE) has been widely accepted for the production of high-pressure fluid conveying pipelines, studies devoted to weldability of PE connections were always of major importance. In this study, two industrial PE grades designed for pipe production, namely PE80 and PE100, were injection molded, cut, and then welded as PE100-PE100, PE100-PE80, and PE80-PE80. The heat-welded joints were assessed by differential scanning...
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The role of hydrodynamic cavitation in tuning physicochemical properties of food items: A comprehensive review
PublikacjaBackground: Today, food processing industries are looking for alternative technologies with an eco-friendly character for the processing of food, beverages and agricultural crops. Ideally, such technologies may preserve the original properties of the food products while reaching their primary target of application. Scope and approach: At this point, hydrodynamic cavitation (HC) is recognized as one of the potential technologies...