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Electrostatic interface recombination in the system of disordered materials characterized by different permittivities
PublicationWe report on the analysis of an electrostatic interface recombination in a system consisting of disordered organic materials. This process is a consequence of the polarization effect which takes place at the interface of two phases characterized by different permittivities. In this paper, the impact of tail and deep localized states on the recombination order is demonstrated. We also discuss the influence of temperature on this...
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Low and high energy explosive materials used in shale gas recovery
PublicationNowadays the explosives are widely used in many areas of life, including industry and mining. A wide range of explosive materials is used in the petroleum industry - from low to high explosives. Recently, as the unconventional oil and gas production became possible, explosives are also found to be used in perforators during the pre-completion stage of the fracturing process. This paper presents literature on theoretical and practical...
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Effects of Addictive Substances During Pregnancy and Infancy and Their Analysis in Biological Materials
PublicationThe use of addictive substances during pregnancy is a serious social problem, not only because of effects on the health of the woman and child, but also because drug or alcohol dependency it detracts from childcare and enhances the prospect of child neglect and family breakdown. Developing additive substance abuse treatment programs for pregnant women is socially important and can help ensure the health of babies, prevent subsequent...
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Non-matrix reference materials-the challenges in the preparation of standard gas mixtures
PublicationIn the last few years particularly great pressure is exerted on quality control and assurance of analytical measurement results. An invaluable role in this process is played by reference materials. The paper presents the characteristics of basic types of reference materials, with particular attention to gaseous reference materials.
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Technological aspects of manufacturing polymer packaging materials degradable in seawater environment
PublicationIn recent years, the number of polymer materials used in the food packaging market was growing extremely fast. This contributed to depletion of non-renewable resources and more intense degradation of the environment due to resistant polymer. Therefore, such a dramatic situation has forced researchers to look for biodegradable materials, decomposable under action of microorganism. Currently, only a small number of researches examine...
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Standard gas mixtures- indispensable reference materials in the analysis of gaseous media
PublicationIn recent years the need for the quality control and assurance of analytical measurement results has been particularly strongly emphasised. Certified reference materials play an invaluable role in this process. The article characterises the basic types of reference materials, focusing in particular on those in the gaseous state. It also reviews the literature on the techniques of preparing standard gas mixtures over the last ten...
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Estimation of optical parameters of highly scattering materials by time-of-flight spectroscopy.
PublicationPrzedstawiono metody wyznaczania podstawowych parametrów materiałów silnie rozpraszających światło na podstawie pomierzonego rozkładu czasu przelotu krótkich impulsów laserowych. W algorytmie wykorzystano metodę Monte Carlo i metodę dyfuzji do opisu propagacji światła. Oszacowano dokładność oszacowywania tych parametrów.
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Analysis of different approaches of capillary rise method for characterization of porous materials
PublicationPomiar kąta zwilżania materiałów porowatych metodą wzniesienia kapilarnego został opisany przez wielu badaczy, jakkolwiek problem ten jest wciąż dyskutowany. Niniejsza praca dotyczy oceny wzniesienia kapilarnego za pomocą równania Washburn'a. Wykonano badania oparte na pomiarze masy i wysokości lustra cieczy zwilżającej w funkcji czasu wzniesienia w złożu wykonanym z kulek szklanych. Uzyskane wyniki były analizowane z użyciem równania...
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Explicit accumulation model for granular materials under multiaxial cyclic loading.
PublicationPróba korelacji parametrów modelu akumulacyjnego piasku z wynikami badań dynamicznych piasku.
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Polysaccharides-Based Hybrid Materials for Bio- and Non-Bio Sectors. Edytorial
PublicationThis special edition spotlights the recent research in the design, development, and emerging applications of polysaccharides-based hybrid materials for biotechnological and biomedical purposes. All the articles published in this issue underscore the significance of materials derived from cellulose, alginate, chitosan, starch, and carrageenan for various applications, including enzyme production, encapsulation, targeted drug delivery,...
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New empirical correlations for the viscosity of selected organic phase change materials
PublicationAlthough there are many methods and instruments for measuring viscosity, it is still difficult to determine a reliable value of the dynamic viscosity of complex chemicals such as paraffins and fatty acids. This is due to the complex and heterogeneous structure of these compounds in the case of commercial products. On the other hand, the measuring instrument should be selected very carefully, including its measuring principle and...
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Theoretical analysis of current induced by high-energetic radiation in dielectric materials
PublicationW pracy poddano analizie mechanizmy generacji i rekombinacji nośników ładunku w obecności wysokoenergetycznego promieniowania. Przedstawiono zależności gęstości prądu elektrycznego od natężenia promieniowania i napięcia polaryzujacego próbkę.
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Effective density of airborne wear particles from car brake materials
PublicationPeople living in urban environments are subject to high health risks due to various anthropogenic sources of airborne particulate matter, including wear of transport vehicle brakes. Studies of airborne particles often require an estimate of the effective particle density, a property that allows correct matching of mass and size characteristics measured by different aerosol instruments. In this study we investigated the effective...
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Emission of 1.3–10 nm airborne particles from brake materials
PublicationOperation of transport vehicle brakes makes a significant contribution to airborne particulate matter in urban areas, which is subject of numerous studies due to the environmental concerns. We investigated the presence and number fractions of 1.3–10 nm airborne particles emitted from a low-metallic car brake material (LM), a non-asbestos organic car brake material (NAO) and a train brake cast iron against a cast iron. Particles...
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Wear measurements of self lubricating bearing materials in small oscillatory movement
PublicationRosnące wymagania ekologiczne powodują wzrost tendencji wymiany klasycznych materiałów łożyskowych, wymagających dodatkowego czynnika smarnego, na materiały nie wymagające smarowania. Zamianie takiej może towarzyszyć obniżenie trwałości zmodernizowanego łożyska. Ten niekorzystny efekt nierzadko obserwuje się w węzłach łożyskowych kierownic turbin wodnych. Autorzy podjęli próbę wyjaśnienia zjawisk występujących w tego typu łożyskach....
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From flow to jamming: Lattice Gas Automaton simulations in granular materials
PublicationWe introduce the first extension of a Lattice Gas Automaton (LGA) model to accurately replicate observed emergent phenomena in granular materials with a special focus on previously unexplored jamming transitions by incorporating gravitational effects, energy dissipation in particle collisions, and wall friction. We successfully reproduce flow rate evolution, density wave formation, and jamming transition observed in experiments....
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Deep learning for ultra-fast and high precision screening of energy materials
PublicationSemiconductor materials for energy storage are the core and foundation of modern information society and play important roles in photovoltaic system, integrated circuit, spacecraft technology, lighting applications, and other fields. Unfortunately, due to the long experiment period and high calculation cost, the high-precision band gap (the basic characteristic parameter) of semiconductor is difficult to obtain, which hinders the...
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Wear of electroplated diamond tools in lap-grinding of Al2O3 ceramic materials
PublicationCurrent development of modern products, together with ever-increasing demands for their operation and usage, necessitate the search for new processing methods. Abrasive machining is widely used in many industrial areas, especially for processing difficult-to-machine materials such as advanced ceramics. Grinding with lapping kinematics, also called lap-grinding, is still one of the innovative methods of abrasive processing being...
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Thermal and technological aspects of double face grinding of Al2O3 ceramic materials
PublicationDouble face grinding with planetary kinematics is a process to manufacture workpieces with plan parallel functional surfaces, such as bearing rings or sealing shims. In order to increase the economic efficiency of this process, it has to be advanced permanently. The temperature in the contact zone of most grinding processes has a huge influence on the process efficiency and the workpiece qualities. In contrast to most grinding...
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Comparison of antimicrobial activity of selected, commercially available wound dressing materials
PublicationOBJECTIVE: The aim of our study was to examine the antimicrobial potential of eight selected, commercially available wound dressings containing different antimicrobial agents: silver, chlorhexidine acetate, povidone-iodine, and manuka honey. METHOD: The materials were tested against four reference strains of bacteria: Staphylococcus aureus (PCM 2051), Staphylococcus epidermidis (PCM 2118), Pseudomonas aeruginosa (ATCC 27853),...
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Application of foam made of post-consumer pet materials for the construction of footbridges
PublicationThe article presents the possibility of application in civil engineering of highly ecological PET foam, manufactured from 100% recycled plastic packaging. It may find uses in construction of numerous engineering structures, such as pedestrian and cycle footbridges. Properly processed waste from post-consumer PET packaging may constitute a quality structural core for use in multilayered composite materials, commonly referred to...
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Application of the expanded clay aggregate in form of granular materials for water treatment
PublicationThe paper aimed to evaluate the efficiency of Filtralite MonoMulti compared to the conventional dual-media filter beds comprising silica sand layer covered with anthracite coal. Filtralite media are composed of processed (expanded), highly porous clay products characterized by relatively rough grain surfaces. In order to compare these different media filters in a reliable way, the pilot filter columns operated in parallel, under...
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Stress Relaxation Behaviour Modeling in Rigid Polyurethane (PU) Elastomeric Materials
PublicationPolyurethane (PU) has been used in a variety of industries during the past few years due to its exceptional qualities, including strong mechanical strength, good abrasion resistance, toughness, low-temperature flexibility, etc. More specifically, PU is easily “tailored” to satisfy particular requirements. There is a lot of potential for its use in broader applications due to this structure–property link. Ordinary polyurethane items...
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Efficiency of Filtering Materials Used in Respiratory Protective Devices Against Nanoparticles
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Coefficients for Assessing the Visibility of Materials Used in Anti-Smog Face Masks
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Modified Polymer Materials for Use in Selected Personal Protective Equipment Products
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Modeling of textural anisotropy in granular materials with stochastic micro-polar hypoplasticity.
PublicationW artykule przedstawiono wyniki numerycznej wpływu anizotropii strukturalnej w materiałach granulowanych na powstawanie lokalizacji odkształceń. Obliczenia wykonano dla ściskania w płaskim stanie odkształcenia stosując metodę elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Wpływ anizotropii modelowano stosując skorelowane pola początkowego wskaźnika porowatości.
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Early prediction of macrocrack location in concrete and other granular composite materials
PublicationHeterogeniczne kruche kompozyty, takie jak beton, ceramika i skały składają się z ziaren połączonych wiązaniami. Pytanie, czy ścieżka pęknięcia, która prowadzi do zniszczenia może być przewidziania na podstawie znanych cech mikrostrukturalnych, a mianowicie łączności wiązań, rozmiaru, energii pękania, wytrzymałości pozostają otwarte. Istnieje wiele kryteriów pęknięć. Najczęściej używane są oparte na postulowanym ekstremum naprężenia...
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Meso‐scale analyses of size effect in brittle materials using DEM
PublicationThe paper describes numerical meso-scale results of a size effect on strength, brittleness and fracture in brittle materials like concrete. The discrete element method (DEM) was used to simulate the size effect during quasi-static splitting tension with the experimental-based meso-structure. The two-dimensional (2D) calculations were carried out on concrete cylindrical specimens with two diameters wherein two different failure...
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Modelling of localization of deformation in quasi-brittle materials with a continuum and discrete model
PublicationW artykule przedstawiono wyniki obliczeń lokalizacji odkształceń w materiałach kruchych przy zastosowaniu 2 modeli w ramach mechaniki ośrodka ciągłego i jednego modelu w ramach ośrodka dyskretnego. W przypadku pierwszy zastosowano model sprężysto-plastyczny i model zniszczeniowy rozszerzony o długość charakterystyczną mikrostruktury. W przypadku drugim przyjęto model rusztowy złożony z beleczek.
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The Application of Granulated Expanded Glass Aggregate with Cement Grout as an Alternative Solution for Sub-Grade and Frost-Protection Sub-Base Layer in Road Construction
PublicationThe purpose of the research was to assess the possibility of using granulated expanded glass aggregate (GEGA) with cement grout as a replacement of a sub-grade and frost-protection layer, made of natural fine aggregates (NATU), stabilized with a hydraulic binder. Instead of traditional parts of the road construction, such as the sub-grade and frost-protection layer with the application of fine aggregate, stabilized with cement,...
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Cellulose Nanomaterials in Biomedical, Food, and Nutraceutical Applications: A Review
PublicationNanotechnology with bionanomaterials have tremendous potential to enhance and utilize for nutrient and bioactive absorption, drug delivery systems, pharmaceutical, and nutraceutical field through various applications. Cellulose nanomaterials are green materials that are obtained from renewable sources and possess exceptional mechanical strength and biocompatibility. The associated unique physical and chemical properties have made...
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A recent developments in polyurethane foams containing a low-cost and pro-ecological modifiers
PublicationDiversity of the polyurethane (PU) foams applications cause that investigation of the relationships between their structure and properties is currently very popular topic among the many research institutions and companies. At the turn of the last years many scientific papers about PU foams and their composites were published. The one of the main research trends in this field is related to the reduction of production costs of...
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Concentration‐Induced Hetero‐Valent Partial‐Inverse Occupation of Infrared Phosphor
PublicationInfrared 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 discussion on infrared phosphors with concentration-induced hetero-valent partial-inverse...
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Preparation and Characterization of Diamond-like Carbon Coatings for Biomedical Applications—A Review
PublicationDiamond-like carbon (DLC) films are generally used in biomedical applications, mainly because of their tribological and chemical properties that prevent the release of substrate ions, extend the life cycle of the material, and promote cell growth. The unique properties of the coating depend on the ratio of the sp3/sp2 phases, where the sp2 phase provides coatings with a low coefficient of friction and good electrical conductivity,...
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Thermomagnetic behavior of a semiconductor material heated by pulsed excitation based on the fourth-order MGT photothermal model
PublicationThis article proposes a photothermal model to reveal the thermo-magneto-mechanical properties of semiconductor materials, including coupled diffusion equations for thermal conductivity, elasticity, and excess carrier density. The proposed model is developed to account for the optical heating that occurs through the semiconductor medium. The Moore–Gibson–Thompson (MGT) equation of the fourth-order serves as the theoretical framework...
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Plasma-Based Deposition and Processing Techniques for Optical Fiber Sensing
PublicationPlasma-based techniques are widely applied for well-controlled deposition, etching or surface functionalization of a number of materials. It is difficult to imagine fabrication of novel microelectronic and optoelectronic devices without using plasma-enhanced deposition of thin films, their selective etching or functionalization of their surfaces for subsequent selective binding of chemical or biological molecules. Depending on...
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Composite Beams with glass and reinforced or prestressed concrete - early stage of a theorethical and experimental analysis of a shear zone
PublicationThe aim of this article is to present a forgoing preparation for a theoretical and experimental analysis of a shear zone of a composite beams with glass and reinforced or prestressed concrete. Authors present their current knowledge, achievements and predicted challenges in later stages of the research. Properties of component materials are presented in the context of compensating weaknesses of one material with strengths of the...
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Nanomateriały o właściwościach magnetycznych, fotokatalitycznych, biobójczych
PublicationTematyka badawcza pracy doktorskiej obejmuje preparatykę i charakterystykę nanomateriałów o właściwościach magnetycznych, fotokatalitycznych, biobójczych. Celem pracy była preparatyka nanomateriałów na bazie TiO2 oraz ZnFe2O4 oraz zastosowanie nanokompozytów w fotokatalizie heterogenicznej do degradacji ksenobiotyków niepodatnych na rozkład biologiczny i otrzymywania funkcjonalnych materiałów budowlanych. Otrzymane nanokompozyty...
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Influence of Laser Modification on the Surface Character of Biomaterials: Titanium and Its Alloys—A Review
PublicationLaser surface modification is a widely available and simple technique that can be applied to different types of materials. It has been shown that by using a laser heat source, reproducible surfaces can be obtained, which is particularly important when developing materials for medical applications. The laser modification of titanium and its alloys is advantageous due to the possibility of controlling selected parameters and properties...
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Fabrication and Characterization of Green Polyurethane Foams with Enhanced Vibration Damping Capability
PublicationOver the past decades, there has been an intensive development of the technologies and innovations aimed at increasing the quality of life. This development largely concerns the comfort of use of everyday products that, among others, are products of the automotive, construction, or furniture industries. Considering the increase in the comfort of using products such as cars, houses, and flats, one of the comfort features of their...
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Influence of Laser Modification on the Surface Character of Biomaterials: Titanium and Its Alloys—A Review
PublicationLaser surface modification is a widely available and simple technique that can be applied to different types of materials. It has been shown that by using a laser heat source, reproducible surfaces can be obtained, which is particularly important when developing materials for medical applications. The laser modification of titanium and its alloys is advantageous due to the possibility of controlling selected parameters and properties...
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Investigation of functional layers of solid oxide fuel cell anodes for synthetic biogas reforming
PublicationSolid oxide fuel cells (SOFCs) are one of the most promising energy conversion devices due to their high efficiency, low pollution and fuel flexibility. Unfortunately, when hydrocarbons are used as a fuel, for example in the form of a biogas, solid carbon can deposit on the anode surface. This process leads to the degradation of the fuel cell performance. A possible solution to this problem is to apply an additional catalytic material,...
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Application of Spinel and Hexagonal Ferrites in Heterogeneous Photocatalysis
PublicationSemiconducting materials display unique features that enable their use in a variety of applications, including self-cleaning surfaces, water purification systems, hydrogen generation, solar energy conversion, etc. However, one of the major issues is separation of the used materials from the process suspension. Therefore, chemical compounds with magnetic properties have been proposed as crucial components of photocatalytic composites,...
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The characterization of collagen‑based scaffolds modified with phenolic acids for tissue engineering application
PublicationThe aim of the experiment was to study the morphology of collagen-based scaffolds modified by caffeic acid, ferulic acid, and gallic acid, their swelling, and degradation rate, as well as the biological properties of scaffolds, such as antioxidant activity, hemo- and cytocompatibility, histological observation, and antibacterial properties. Scaffolds based on collagen with phenolic acid showed higher swelling rate and enzymatic...
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Structural, electrical, and magnetic study of La-, Eu-, and Er- doped bismuth ferrite nanomaterials obtained by solution combustion synthesis
PublicationIn this work, the multiferroic bismuth ferrite materials Bi0.9RE0.1FeO3 doped by rare-earth (RE = La, Eu, and Er) elements were obtained by the solution combustion synthesis. Structure, electrical, and magnetic properties of prepared samples were investigated by X-ray photoelectron spectroscopy, Mössbauer spectroscopy, electrical hysteresis measurement, broadband dielectric spectroscopy, and SQUID magnetometry. All obtained nanomaterials...
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Foamed Polyurethane Composites With Different Types of Ash – Morphological, Mechanical and Thermal Behavior Assessments
Publicationncorporation of two types of ash particles into flexible polyurethane foams has been investigated, wood ash from gasification process and fly ash resulting from coal burning in power plant. Samples were modified with 5, 10 and 15 wt% of fillers. Structure, mechanical and thermal properties of obtained foams were investigated. Incorporation of both types of ash particles resulted in materials showing...
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The Influence of Iron Doping on Performance of SrTi1-XFexO3-δ Perovskite Oxygen Electrode for SOFC
PublicationSolid Oxide Fuel Cells (SOFC) are based on electrolytes and mixed ionic and electronic conductivity (MIEC) materials. The need to reduce costs causes an increase in interest of new compounds suitable for operating temperatures between 600 °C and 800 °C. The SrTi1-xFexO3 (STF) perovskite material is a perspective material that could be used for the oxygen electrodes. In this work STF materials with different content of iron (x =...
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Hard carbon derived from rice husk as low cost negative electrodes in Na-ion batteries
PublicationHere, we report the synthesis of hard carbon materials (RH) made from natural rice husk through a single pyrolysis process and their application as an anode in sodium-ion batteries. The studies show that the electrochemical properties of RHs are affected by the treatment temperatures, which determine the materials morphology, in particular, their degree of graphitization and extent of continuous channels (nanovoids). The latter...
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Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies
PublicationRecently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal...