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Wyniki wyszukiwania dla: INSECT WING MATERIALS
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Numerical analysis by FEM and analytical study of the dynamic thermal behavior of hollow bricks with different cavity concentration
PublikacjaThis paper presents the investigation results on the influence of the cavity concentration in hollow bricks on static and dynamic thermal parameters: a time lag, a decrement factor, an equivalent thermal diffusivity (ETD) and an equivalent thermal conductivity (ETC). The dynamic thermal behavior of hollow bricks is studied with an optimized cavity shape to reduce the intensity of radiation and convective heat exchange. The thermal...
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Method of managing drill cuttings from shale gas formations
PublikacjaProposed management method of drill cuttings involves recycling for the expanded clay production. A theoretical presentation of the possibility, choosing planning path based on similarity between the materials used in the manufacture of expanded clay and oily cuttings. Application for the main stages of manufacture of expanded clay production of drill cuttings from shale gas extraction. Introduced into circulation solid waste partly...
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Application of magnetic nanoparticles for magnetic solid-phase extraction in preparing biological, environmental and food samples
PublikacjaThe need to obtain meaningful results as the basis for determining the content of trace amounts of analytes has become the driving force behind the development of modern analytical techniques, including sample-preparation techniques, such as solid-phase extraction (SPE). Recently, great interest was aroused in the use of magnetic nanoparticles (MNPs) in SPE. These materials exhibit high selectivity, and, in small amounts, can provide...
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Investigation of an elutable N-propylphosphonic acid chitosan derivative composition with a chitosan matrix prepared from carbonic acid solution
PublikacjaPorous chitosan composites using CO2 dissolution procedure and including water soluble N-propylphosphonic chitosan derivative (p-CHI) were obtained and characterized. In contrast to the control material, composites containing modified chitosan distinguished by a rapid moisture absorption and good adhesion to the skin. The FTIR analysis confirmed the presence of propylphosphonic group in the structure of the polymer. The porosity...
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Nanoparticles displacement analysis using optical coherence tomography
PublikacjaOptical coherence tomography (OCT) is a versatile optical method for cross-sectional and 3D imaging of biological and non-biological objects. Here we are going to present the application of polarization sensitive spectroscopic OCT system (PS-SOCT) for quantitative measurements of materials containing nanoparticles. The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. In this contribution the benefits...
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Structure and thermoelectric properties of Bi–Te alloys obtained by novel method of oxide substrates reduction
PublikacjaA novel method of thermoelectric materials fabrication has been developed. Oxide reagents have been melted at high temperature in air, quenched, milled to powder and reduced in hydrogen to form Bi–Te alloys. Structural and thermoelectric properties of samples have been investigated depending on initial composition and temperature of reduction process. Sample 25Bi2O3–75TeO2 reduced at 340 °C for 10 h has been found to be a p-type...
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Morphology and properties of recycled polyethylene/ground tyre rubber/thermoplastic poly(ester-urethane) blends
PublikacjaThe growing amount of plastics waste produced every year resulted in development of mechanical and chemical recycling methods of polymers and their blends or composites. From the environmental point of view, the possibility of plastics waste reusing and recycling is desirable. In this study three polymer blends were obtained with using recycled polyethylene (RPE), ground tyre rubber (GTR) and thermoplastic poly(ester-urethane)...
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Optimization of Graphene Oxide Synthesis and Its Reduction
PublikacjaIn this article, we present the review of the chemical methods of synthesis of graphene oxide and its reduction in order to obtain the so-called reduced graphene oxide (rGO) whose properties are similar to those of pure graphene. We also present our experiments and the results in this field and the comparison of the efficiency of different methods of synthesis as well as the reduction of graphene oxide. To characterize the obtained...
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Ceramic composites for single-layer fuel cells
PublikacjaComposite materials consisting of acceptor doped lanthanum orthoniobate electrolyte phase (La0.98Ca0.02NbO4) and Li2O:NiO:ZnO semiconducting phase were synthesized. The precursor powder of La0.98Ca0.02NbO4 was prepared in nanocrystalline (mechanosynthesis) and microcrystalline (solid-state synthesis) form. The composite can be applied in a single-layer fuel cell, because of the presence of two phases acting as an anode and a cathode...
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Application of the Barkhausen effect probe with adjustable m agnetic field direction for stress state determination in the P91 ste el pipe
PublikacjaThe paper presents the results of application of a novel Barkhausen effect (BE) probe with adjustable magnetizing field direction for the stress level evaluation in ferromagnetic materials. The investigated sample was in a form of a pipe, made of P91 steel that was anisotropic due to the production process. The measurements were performed before and after welding, revealing the influence of welding process on the residual stress...
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The influence of polymer bearing material and lubricating grooves layout on wear of journal bearings lubricated with contaminated water
PublikacjaThe goal of the present paper is to investigate wear properties of journal sliding bearing operating in the conditions of contaminated water lubrication. Several bearing materials and bearing sleeve designs (differing in the axial grooves position and their shape) were tested experimentally under typical operating conditions in a dedicated test rig, which was equipped with a lubricating system, enabling lubrication with contaminated...
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A dual-control strategy based on electrode material and electrolyte optimization to construct an asymmetric supercapacitor with high energy density
PublikacjaMetal-organic frames (MOFs) are regarded as excellent candidates for supercapacitors that have attracted much attention because of their diversity, adjustability and porosity. However, both poor structural stability in aqueous alkaline electrolytes and the low electrical conductivity of MOF materials constrain their practical implementation in supercapacitors. In this study, bimetallic CoNi-MOF were synthesized to enhance the electrical...
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Electrical properties of organic and perovskite systems used in solar cells
PublikacjaNowadays, a great progress in the areas of molecular and hybrid photovoltaics is observed. The devices based on organic and perovskite materials are getting attention mostly due to their low cost production process. However, their efficiency and stability are still lower than for inorganic materials which make them less popular. Therefore, a detailed understanding of the device physics is fundamental for organic and perovskite...
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Fractal dimension for bending–torsion fatigue fracture characterisation
PublikacjaFracture surfaces after biaxial fatigue tests were compared using fractal dimension for three types of metallic materials in smooth and notched specimens made of S355J2 and 10HNAP steels and 2017-T4 aluminium alloy, considering both proportional and nonproportional cyclic loading. High-resolution optical 3D measurement studies were performed on the entire fracture surface. A direct correlation between fractal dimension and fatigue...
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Therapeutic biomaterials - application in neurology and cardiology
PublikacjaBiomaterials are of interest in most medical fields. It's hard to imagine life without them. And due to the ever-increasing demand, scientists are developing new materials. Diseases of the nervous and cardiovascular systems are still a big problem, which are associated with a limited ability to regenerate brain or heart tissues. Therefore, this review discusses the advancement in biomaterial engineering for the treatment of neurological...
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Therapeutic biomaterials – application in neurology and cardiology
PublikacjaBiomaterials are of interest in most medical fields. It's hard to imagine life without them. And due to the ever-increasing demand, scientists are developing new materials. Diseases of the nervous and cardiovascular systems are still a big problem, which are associated with a limited ability to regenerate brain or heart tissues. Therefore, this review discusses the advancement in biomaterial engineering for the treatment of neurological...
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Enhanced Electrochemical Performance of MnCo1.5Fe0.5O4Spinel for Oxygen Evolution Reaction through Heat Treatment
PublikacjaMnCo1.5Fe0.5O4 spinel oxide was synthesized using the sol−gel technique, followed by heat treatment at various temperatures (400, 600, 800, and 1000 °C). The prepared materials were examined as anode electrocatalysts for watersplitting systems in alkaline environments. Solid-state characterization methods, such as powder X-ray diffraction and X-ray absorption spectroscopy (XAS), were used to analyze the materials’ crystallographic...
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Preparation and characterisation of iron substituted Mn1.7Cu1.3-xFexO4 spinel oxides (x = 0, 0.1, 0.3, 0.5)
PublikacjaSpinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical...
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Numerical analysis by FEM and analytical study of the dynamic thermal behavior of hollow bricks with different cavity concentration
PublikacjaThis paper presents the investigation results on the influence of the cavity concentration in hollow bricks on static and dynamic thermal parameters: a time lag, a decrement factor, an equivalent thermal diffusivity (ETD) and an equivalent thermal conductivity (ETC). The dynamic thermal behavior of hollow bricks is studied with an optimized cavity shape to reduce the intensity of radiation and convective heat exchange. The thermal...
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iPP/HDPE blends compatibilized by a polyester: An unconventional concept to valuable products
PublikacjaPolyolefins are the most widely used plastics accounting for a large fraction of the polymer waste stream. Although reusing polyolefins seems to be a logical choice, their recycling level remains disappointingly low. This is mainly due to the lack of large-scale availability of efficient and inexpensive compatibilizers for mixed polyolefin waste, typically consisting of high-density polyethylene (HDPE) and isotactic polypropylene...
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Novel Research on Biomedical Polyurethanes
PublikacjaThe variety of mechanical properties characterizes properly designed PURs. They may be biocompatible and reveal compatibility with blood, making them attractive materials for the fabrication of tissue scaffolds; however, like all synthetic materials, PURs don’t reveal sufficient biocompatibility. PURs may undergo certain chemical modifications (e.g., 1,4:3,6-dianhydro-D-sorbitol, ascorbic acid (AA), growth factors, covering with...
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The investigation of polyester composites filled by modified bentonite
PublikacjaPraca dotyczy zagospodarowania odpadów poliestrowo-szklanych przez wytworzenie kompozytów z ich użyciem oraz żywicy poliestrowej, mączki dolomitowej i nanonapełniacza. Wykazano, ze dodatek 2% nanonapełniacza do do kompozytów poliestrowych zawierających 15% masowych odpadów pozwala na uzyskanie materiału wykazującego korzystne właściwości wytrzymałościowe. Proponowany sposób modyfikacji kompozytów poliestrowych jest nowym rozwiązaniem...
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Electrical characterization of diamond/boron doped diamond nanostructures for use in harsh environment applications
PublikacjaThe polycrystalline boron doped diamond (BDD) shows stable electrical properties and high tolerance for harsh environments (e.g. high temperature or aggressive chemical compounds) comparing to other materials used in semiconductor devices. In this study authors have designed electronic devices fabricated from non-intentionally (NiD) films and highly boron doped diamond structures. Presented semiconductor devices consist of highly...
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SILICA AEROGEL TOWARDS ANODES FOR LITHIUM-ION BATTERIES
PublikacjaAn increasing demand for electrochemical energy storage and conversion devices stimulates progress in research on electrode and electrolyte materials. In the field of electrodes materials, silicon is the one of the most promising anode materials for Li-ion batteries. However silicon has the drastic volume variation (around 3 times lower on extraction) during insertion and extraction of lithium ions. As an alternative, nanocomposites...
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Structural investigations of niobium-doped bioactive calcium-phosphate glass-ceramics by means of spectroscopic studies
PublikacjaSynthetic calcium-phosphate based glasses and glass-ceramics play a crucial role in the development of tissue engineering. These materials have a high biocompatibility with biological analogues, excellent ability to undergo varying degrees of resorbability and due to their non-toxicity and relatively high bioactivity they are commonly used as bone and dental implants. A substantial research effort is devoted to improve synthetic...
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Photocatalytic activity of zinc oxide nanorods incorporated graphitic carbon nitride catalyst
PublikacjaBackground Photocatalysts are user-friendly and serve as compatible materials for degrading industrial dye pollutants. This study utilizes zinc oxide/graphitic carbon nitride (ZnO/g-C3N4) nanocomposites against degrading methylene blue (MB). Methods The hydrothermal method assisted sonication technique was used to fabricate the ZnO/g-C3N4 composite with varying ratios of ZnO/g-C3N4 (1:0.25, 1:0.50, 1:1). The synthesized materials...
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THE ROLE OF DAYLIGHT IN ARCHITECTURAL CREATIONS OF CONTEMPORARY CULTURAL FACILITIES
PublikacjaThe paper studies the role of light in architectural creations of contemporary buildings of representative function. Based on the selected projects and completed buildings dedicated to culture and art, it analyzes and systematizes the examples of using light to obtain visual effects that mark the architecture with a universal and timeless message. The method of research is case study and critical analysis of literature. Light plays...
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One Year Evaluation of Material Properties Changes of Polylactide Parts in Various Hydrolytic Degradation Conditions
PublikacjaBiodegradable biocompatible materials are widely used in medical applications. Determining the possibility of using biodegradable materials depends on determining the changes in their parameters over time due to degradation. The current scientific research on biodegradable materials has presented results based on research methods characterized by the different geometry and cross-section size of the specimen, type of degradation...
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Effect of Polymerization Statistics on the Electronic Properties of Copolymers for Organic Photovoltaics
PublikacjaStatistical block copolymers, composed of donor (D) and acceptor (A) blocks, are a novel type of material for organic photovoltaics (OPVs) devices. In particular a new series of polymers based on PBTZT-stat-BDTT-8, recently developed by Merck, offers high solubility in different solvents, and a high power conversion efficiency (PCE) in different device architectures. Although it is known that the electronic properties of these...
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Nano-particle doped hydroxyapatite material evaluation using Spectroscopic Polarization Sensitive Optical Coherence Tomography
PublikacjaBio-ceramics such as hydroxyapatite (HAp) are widely used materials in medical applications, especially as an interface between implants and living tissues. There are many ways of creating structures from HAp like electrochemical assisted deposition, biomimetic, electrophoresis, pulsed laser deposition or sol-gel processing. Our research is based on analyzing the parameters of the sol-gel method for creating thin layers of HAp....
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Synergistic effects of nitrogen-doped carbon and praseodymium oxide in electrochemical water splitting
PublikacjaHybrid materials featuring perovskite-type metal oxide in conjunction with heteroatom-doped graphene hold immense promise as alternatives to costly noble metal catalysts for electrochemical water splitting, facilitating the generation of environmentally friendly hydrogen. In this study, perovskite-type oxide containing praseodymium, barium, strontium, cobalt, and iron atoms dispersed in a carbon matrix as a catalyst is synthesized...
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Ecology In Tribology: Selected Problems of Eliminating Natural Oil-Based Lubricants from Machine Friction Couples
PublikacjaThe elimination of mineral oil-based lubricants from machines has multiple beneficial effects on the natural environment. Firstly – these lubricants are a direct threat to the environment in the event of leaks; secondly – their elimination reduces the demand for crude oil from which they are obtained. In addition, in many cases, e.g. when replacing traditional lubricants with water, friction losses in the bearings can also be reduced...
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Nanocrystallization as a tool for controlling in vitro dissolution of borophosphate glass
PublikacjaThe controlled nanocrystallization of sodium-calcium-borophosphate glass (Na16.6Ca5.1B10.5Al0.8P10.5 O56.5 in at %) was conducted to investigate its influence on in vitro dissolution. Three temperatures (570 ◦C, 590 ◦C, and 610 ◦C) were selected based on thermal analysis and investigation of the morphology, structure, and in vitro dissolution of glass and glass-ceramics was conducted. The results of X-ray diffraction confirmed...
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Nanolayers in Fiber-Optic Biosensing
PublikacjaIn this chapter, fiber-optic sensors based on nanolayers or thin films and their ability to perform biophotonic measurements is presented. In the last decade, fiber-optic sensors have gained popularity as biosensing devices. This has been made possible because of the design and the integration of new materials in fiber-optic technology. Nanolayers and thin films made from various materials such as nanodiamond (NCD), boron-doped...
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Testing and sampling devices for monitoring volatile and semi-volatile organic compounds in indoor air
PublikacjaAdults spend most of their time in enclosed spaces (e.g., apartment, office and public buildings). According to research conducted by scientists, air quality indoors is much worse than the ambient air quality outdoors. Hazardous chemicals found in air indoors can adversely affect the functioning of the human body and cause many respiratory and circulatory diseases. Harmful chemical compounds (mainly volatile organic compounds and...
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Polytypism and superconductivity in the NbS2 system
PublikacjaWe report on the phase formation and the superconducting properties in the NbS2 system. Specifically, we have performed a series of standardized solid-state syntheses in this system, which allow us to establish a comprehensive synthesis map for the formation of the two polytypes 2H-NbS2 and 3R-NbS2, respectively. We show that the identification of two polytypes by means of X-ray diffraction is not always unambiguous. Our physical...
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Application of advanced spectroscopic methods in the assessment of the leachability degree of hazardous elements from the matrix of cellular concretea
PublikacjaDue to its structure, autoclaved cellular concrete exhibits good insulating properties with relatively high compressive strength values. It is increasingly used in construction because of its economic attractiveness. Autoclaved cellular concrete is mainly used in interior structure layers, and therefore its potential exposure to heavy metal leaching from the matrix may be related to the presence of a high pH medium from other materials...
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Photoluminescence of partially reduced Eu2+/Eu3+ active centers in a NaF–Al2O3–P2O5 glassy matrix with tunable smooth spectra
PublikacjaIn this work, a series of photoluminescent materials have been synthesized based on optically transparent and chemically stable glasses of the nominal composition Na3Al2(PO4)2F3 (NaF–Al2O3–P2O5 system) doped with 1 wt% of europium. It has been shown that the synthesis conditions (mainly the temperature and duration of the melting stage under reducing conditions) strongly affected the photoluminescence spectra of the material. This...
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Wykorzystanie Web 2.0 oraz architektury informacji w pracy brokera informacji = TAKING ADVANTAGE OF WEB 2.0 AND THE INFORMATION ARCHITECTURE IN THE INFORMATION BROKER’S WORK
PublikacjaThe development of information and communication technologies, dissemination of access as well as unlimited increase of publications result in the uncontrolled growth of knowledge resources. Looking up for the relevant information becomes increasingly difficult, especially when time plays a role. Such process requires vast knowledge, practical experience in obtaining and providing information and also analytical...
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Reclaimed Rubber/Poly(ε‐caprolactone) Blends: Structure, Mechanical, and Thermal Properties
PublikacjaThe amount of elastomeric waste, especially from tires is constantly increasing on a global scale. The recycling of these residua should be considered a priority. Compounding the waste rubbers with other polymers can be an excellent alternative to reuse waste materials. This procedure requires solving the issue of the lack of compatibility between the waste rubber particles and other polymers. Simultaneously, there is a claim for...
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Graphene field-effect transistor application for flow sensing
PublikacjaMicroflow sensors offer great potential for applications in microfluidics and lab-on-a-chip systems. However, thermal-based sensors, which are commonly used in modern flow sensing technology, are mainly made of materials with positive temperature coefficients (PTC) and suffer from a self-heating effect and slow response time. Therefore, the design of novel devices and careful selection of materials are required to improve the overall...
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Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review
PublikacjaThermoplastic polyurethanes (TPUs) materials are obtained by the reaction of polyol (ether-, ester-, and carbonate-based diols with average molecular weight in the range from 1,000 to 3,000 g/mol) with aliphatic or aromatic diisocyanates. Synthesized materials consist of the hard and soft segments which are separated in different level. All mechanical and thermal properties of TPUs depend on the chemical structure of used monomers,...
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Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
PublikacjaThe Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical...
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Progress in used tyres management in the european union: a review
PublikacjaThe dynamic increase in the manufacture of rubber products, particularly those used in the automobile industry, is responsible for a vast amount of wastes, mostly in the form of used tyres, of which more than 17 million tonnes are produced globally each year. The widely differing chemical compositions and the cross-linked structures of rubber in tyres are the prime reason why they are highly resistant to biodegradation, photochemical...
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Recent applications and future prospects of magnetic biocatalysts
PublikacjaMagnetic biocatalysts combine magnetic properties with the catalytic activity of enzymes, achieving easy recovery and reuse in biotechnological processes. Lipases immobilized by magnetic nanoparticles dominate. This review covers an advanced bibliometric analysis and an overview of the area, elucidating research advances. Using WoS, 34,949 publications were analyzed and refined to 450. The prominent journals, countries, institutions, and...
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Morphology of damage inflicted on brittle polymer in lubricated contact under cyclic static load
PublikacjaIn this article morphology of damage inflicted on the polymethylmethacrylate (PMMA) plate in static point lubricated contact with a ball made of five different materials under cyclic normal load has been presented. It is argued that the counterface material and lubricating film play an important role in the damage process and the extent of damage inflicted in the PMMA plate.
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Titanium Scaffolds – Hopes and Limitations
PublikacjaThe state-of-art on titanium scaffolds is briefly reviewed. The real hopes from medicine associated with scaffolds are indicated. The limitations of different scaffolds associated with their mechanical, chemical and biological properties are discussed. The great importance of titanium scaffolds is demonstrated as the materials of high biocompatibility and corrosion resistance, fair mechanical properties and important biological...
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Otwarte zasoby edukacyjne - przegląd inicjatyw w Polsce i na świecie
PublikacjaOtwarte zasoby edukacyjne (OZE) to materiały szkoleniowe oraz narzędzia wspierające zarówno uczenie, jak i nauczanie. Zjawisko to nierozerwalnie łączy się z szerszym pojęciem otwartej edukacji (OE), które postuluje zniesienie barier w nauczaniu tak, aby uczący się mogli zdobywać wiedzę zgodnie ze swoimi potrzebami edukacyjno-szkoleniowymi. Celem artykułu jest zapoznanie czytelników z zagadnieniem otwartych zasobów edukacyjnych,...
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Wytwarzanie i modyfikacja powierzchni porowatych struktur tytanowych przeznaczonych na implanty
PublikacjaCelem pracy było wytworzenie stopu Ti-13Nb-13Zr z wykorzystaniem technologii selektywnego topienia laserowego (SLM) oraz jego biofunkcjonalizacja za pomocą utleniania mikrołukowego (MAO), a następnie określenie wpływu parametrów procesowych na właściwości otrzymanych materiałów pod kątem ich zastosowania na implanty. Oceniono wpływ napięcia, natężenia i czasu procesu MAO przeprowadzanego w elektrolicie zawierającym wapń i fosfor...
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PROBLEMY ZWIĄZANE Z ZASTOSOWANIEM NANOTECHNOLOGII W TERMOIZOLACJI BUDYNKÓW
PublikacjaBudownictwo i architektura były zawsze ściśle związane z rozwojem technologicznym a ciągły postęp w badaniach nad inżynierią materiałową pozwalał na uzyskiwanie bardziej wydajnych i wytrzymałych materiałów. Dotyczy to nie tylko elementów konstrukcyjnych budynku ale także technologii związanych z jego wykończeniem. Obecnie coraz większą rolę w budownictwie i architekturze odgrywa pojęcie nanotechnologii. Dziedzina nauki, zdawałoby...