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Shore Construction Detection by Automotive Radar for the Needs of Autonomous Surface Vehicle Navigation
PublicationAutonomous surface vehicles (ASVs) are becoming more and more popular for performing hydrographic and navigational tasks. One of the key aspects of autonomous navigation is the need to avoid collisions with other objects, including shore structures. During a mission, an ASV should be able to automatically detect obstacles and perform suitable maneuvers. This situation also arises in near-coastal areas, where shore structures like...
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Behaviour of steel columns under impact
PublicationOne of import issues related to the idea of sustainable society is the safety of civil engineering structures. The safety and reliability of steel structures under impact loading is among a number of different aims during the design state. The aim of this paper is to present the results of investigation focused on dynamic behaviour of steel columns under impact loading. Modal and transient dynamic analyses using Finite Element...
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Cuticular lipids of insects as potential biofungicides
PublicationThe term ''lipids'' refers to fatty acids, their derivatives and substances related with them biochemically or by the functions in the body. Lipids include compounds with different chemical structure. There are lipids with structures based on long-chain carboxylic acids and their direct derivatives, namely: fatty acids, alkanes, some alkenes, aldehydes and long chain alcohols and their derivatives (esters). The variety of lipid...
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Design of a microrobotic wrist for needle laparoscopic surgery
PublicationThe paper addresses the design of a micro wrist for needle laparoscopic surgery (needlescopy) using MEMS technology and an original 3 degree of freedom, 3D architecture. Advancement in needlescopy drives the development of multi-dof micro-tools 1-2mmin diameter with 3D mobility but standard available fabricationtechniques are for 2.5D structures. The paper discusses thedevelopment steps and design solutions for the realization...
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Response of a steel tank during earthquakes and mining tremors - experimental investigation
PublicationCylindrical steel tanks are very popular shell structures used to store the products of chemical and petroleum industries. Any failure might have disastrous consequences, therefore their safety and reliability is essential. Earthquakes are the most dangerous and also the most unpredictable dynamic loads acting on such structures. On the other hand, mining tremors are usually considered to be less severe due to lower acceleration...
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COMPARISON OF INFINITE ELEMENT MODELS
PublicationThe main objective of this paper is to show the comparison of two models of infinite ab- sorbing layer with increasing damping in numerical investigations of elastic wave prop- agation in unbounded structures. This has been achieved by the Authors by a careful in- vestigation of two different engineering structures characterised by gradually increasing geometrical and mathematical description complexities. The analysis included...
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Ergonomics in Polish outpatient clinics
PublicationOutpatient clinics are structures In which ergonomics play a key role. This fact is associated with an often occurring risk of developing hospital-acquired infection. The risk increases with mistakes made in wrong planning the functional and spatial lay-out is subordinated to high utilitarian requirements, including hygienic and sanitary, and technological requirements. A properly planned structure allows to reduce dangers more...
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Identification of Kinematic Excitation Function by the Modal Coordinates Estimation of the System's Dynamics
PublicationThe paper presents a method of the kinematic excitation courses’ identification in excitation points, based on the car road test acceleration at different measurement points. For the purpose of the laboratory fatigue life investigation of contemporary complex structures (e.g. cars bodies) and components of these structures (i.e. cars roofs), only a few first vibration modes are usually taken into account. During real life tests...
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Selected Stability Problems of Thin-Walled Columns and Beams
PublicationThe article reviews a number of papers in the light of buckling analy- sis of thin-walled columns and beams. Stability of thin-walled columns and beams are considered a vital engineering science issue in both historical and present-day approaches. The paper refers to the recent authors’ works of the 2012–2019 period, published in leading journals. Similar review of stability problems of thin-walled structures developed at Gdansk...
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A novel heterogeneous model of concrete for numerical modelling of ground penetrating radar
PublicationThe ground penetrating radar (GPR) method has increasingly been applied in the non-destructive testing of reinforced concrete structures. The most common approach to the modelling of radar waves is to consider concrete as a homogeneous material. This paper proposes a novel, heterogeneous, numerical model of concrete for exhaustive interpretation of GPR data. An algorithm for determining the substitute values of the material constants...
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Timber Frame Houses with Different Insulation Materials - Seismic Analysis
PublicationThe aim of this article is to present results of a dynamic numerical analysis focused on the response of two timber frame building structures exposed to seismic excitations. The first structure was insulated with mineral wool, while the second one with polyurethane foam. Specifications and technology involved in the models' construction are based on the previously conducted experimental study, upon which numerical structural models...
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Structural and Material Determinants Influencing the Behavior of Porous Ti and Its Alloys Made by Additive Manufacturing Techniques for Biomedical Applications
PublicationOne of the biggest challenges in tissue engineering is the manufacturing of porous structures that are customized in size and shape and that mimic natural bone structure. Additive manufacturing is known as a sufficient method to produce 3D porous structures used as bone substitutes in large segmental bone defects. The literature indicates that the mechanical and biological properties of scaffolds highly depend on geometrical features...
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Hydrogen and chalcogen bonds in crystals of chalcogenadiazolecarboxylic acids – competition or cooperation?
PublicationThis 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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A Review: Structural Shape and Stress Control Techniques and their Applications
PublicationThis review article presents prior studies on controlling shape and stress in flexible structures. The study offers a comprehensive survey of literature concerning the adjustment and regulation of shape, stress, or both in structures and emphasizes such control’s importance. The control of systems is classified into three primary classes: nodal movement control, axial force control, and controlling the two classes concurrently....
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A Review of Hyperelastic Constitutive Models for Dielectric Elastomers
PublicationDielectric elastomers are smart materials that are essential components in soft systems and structures. The core element of a dielectric elastomer is soft matter, which is mainly rubber-like and elastomeric. These soft materials show a nonlinear behaviour and have a nonlinear strain-stress curve. The best candidates for modelling the nonlinear behaviour of such materials are hyperelastic strain energy functions. Hyperelastic functions...
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Intermolecular Hydrogen Bonding Directed by Aryl–Perfluoroaryl π–π Stacking Interactions
PublicationThe crystal structures of five compounds capable of forming self-complementary hydrogen bonds but crystallizing as catemers or creating more complex crystal structures were compared with their complexes prepared by cocrystallization with perfluoroaryl compounds. The results of X-ray diffraction revealed that in all the cases the π–π stacking interactions caused reorganization of hydrogen bonds and induced creation of the expected...
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Biomimetic torene shells
PublicationThe genome inside the eukaryotic cells is guarded by a unique shell structure, called the nuclear envelope (NE), made of lipid membranes. This structure has an ultra torus topology with thousands of torus-shaped holes that imparts the structure a high flexural stiffness. Inspired from this biological design, here we present a novel ‘‘torene’’ architecture to design lightweight shell structures with ultra-stiffness for engineering...
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CORROSION TESTING OF SAMPLES ACCORDING TO ASTM G36
PublicationAt the end of the study, samples were found to have structures characteristic for intercrystalline corrosion. This indicates that the samples provided (fragments of the whole) were sensitized before starting the study in boiling MgCl2.On cross sections, fine cracks are observed on all samples tested.
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Knowledge management in SMEs - theoretical considerations.
PublicationThe purpose of this chapter is to present an analysis of knowledge management concept with regard to small and medium-sized enterprises. It is aimed to propose an overview for SMEs to apply this above-mentioned concept. This overview can be used by managers and owners of SMEs to introduce knowledge management into their organizational structures.
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Quasi-Static Response
PublicationConcern for the quasi-static response of ship and offshore structures, as required for safety and serviceability assessments. Attention shall be given to uncertainty quantification of quasi-static load and response analysis approaches, and their limitations, including exact and approximate methods for derivation of different acceptance criteria.
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Diagnosis of Damage in a Steel Tank with Self-Supported Roof through Numerical Analysis
PublicationThe safety of civil engineering structures is one of the most important issues of building industry. That is why the assessment of the damage-involved structural response has recently become of major concern to engineers. Among a number of different approaches to diagnosis of damage, the method of measuring the changes in natural frequencies is considered to be one of the most effective indicators of global damage. From the practical...
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Experimental study on effectiveness of polymer dampers in reduction of structural vibrations
PublicationVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Experimental study on the effectiveness of polymer dampers in reduction of structural vibrations
PublicationVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Linear revitalization - problems and challenges. Discursive article
PublicationThe aim of the article, defined by the author as discursive, is to give the answer as to whether within ‘revitalization’ we should distinguish the notion of ‘linear revitalization’ – not yet defined in Polish and English-language literature. The author presents the thesis that we should do so by presenting the idea, its specific character and its role. This kind of action seems to have, in the author’s opinion, a positive influence...
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Study on Methods to Control Interstory Deflections
PublicationOne of the possibilities to prevent building pounding between two adjacent structures is to consider appropriate in-between separation distance. Another approach might be focused on controlling the relative displacements during seismic excitations. Although the majority of building codes around the world recommend the use of some equations of various distances between structures to avoid pounding; a lot of reports after earthquakes...
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Experimental and Numerical Study on Dynamics of Two Footbridges with Different Shapes of Girders
PublicationThe paper presents the experimental and numerical results of the dynamic system identification and verification of the behavior of two footbridges in Poland. The experimental part of the study involved vibration testing under different scenarios of human-induced load, impulse load, and excitations induced by vibration exciter. Based on the results obtained, the identification of dynamic parameters of the footbridges was performed...
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Mapping the Transglycosylation Relevant Sites of Cold-Adapted β-D-Galactosidase from Arthrobacter sp. 32cB
PublicationB-Galactosidase from Arthrobacter sp. 32cB (ArthbetaDG) is a cold-adapted enzyme able to catalyze hydrolysis of beta-D-galactosides and transglycosylation reaction, where galactosyl moiety is being transferred onto an acceptor larger than a water molecule. Mutants of ArthbetaDG D207A and E517Q were designed to determine the significance of specific residues and to enable formation of complexes with lactulose and sucrose and to...
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Performance-Based Nested Surrogate Modeling of Antenna Input Characteristics
PublicationUtilization of electromagnetic (EM) simulation tools is mandatory in the design of contemporary antenna structures. At the same time, conducting designs procedures that require multiple evaluations of the antenna at hand, such as parametric optimization or yield-driven design, is hindered by a high cost of accurate EM analysis. To certain extent, this issue can be addressed by utilization of fast replacement models (also referred...
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Research on GNSS satellite navigation systems
PublicationThis article contains results of research on two GNSS systems, i.e. GPS and GLONASS. Architectures, signal structures and navigation messages of both systems have been described. Some selected investigation results, concerning receiver performance in presence of interference, have been presented.
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Effect of Pendolino high-speed rail on the structure of buildings located the proximity of the railway tracks
PublicationThe following research focuses on the dynamic analysis of the impact of the high-speed train inducted vibrations on the structures located near railway tracks. The office complex chosen as the subject of calculations is located in the northern part of Poland, in Gdańsk, in the proximity of Pendolino, the high speed train route. The high speed trains are the response for the growing needs for more efficient railway system. However...
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Reliable low-cost surrogate modeling and design optimisation of antennas using implicit space mapping with substrate segmentation
PublicationAbstract: In this work, a reliable methodology for fast simulation-driven design optimisation of antenna structures is proposed. The authors’ approach exploits implicit space mapping (ISM) technology. To adopt it for handling antenna structures, they introduce substrate segmentation with separate dielectric permittivity value assigned for each segment as ISM preassigned parameters. At the same time, the coarse model for space mapping...
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Compact 4 × 4 butler matrix with non‐standard phase differences for IoT applications
PublicationButler matrices represent a popular class of feeding networks for antenna arrays. Large dimensions and the lack of flexibility in terms of achievable output phase difference make conventional Butler structures of limited use for modern communication devices. In this work, a compact planar 4 × 4 matrix with non-standard relative phase shifts of –30º, 150º, –120º, and 60º has been proposed. The structure is designed to operate at...
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Portico Farmhouses of the Vistula Delta: Architecture, Current State and Finite Element Modelling of Timber Roof Truss under Material and Cross-section Uncertainty
PublicationThe article focuses on the oldest surviving I-type portico houses located in the Vistula Delta, which were built in the 17th and 18th centuries. The study describes the houses’ origins, structure, details of roof structures and technical condition, and it also includes numerical modelling of a roof truss and its mechanical analysis. Numerical models of the roof trusses are defined and analysed by means of the finite element method....
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Finite element/mode-matching analysis of ferrite/dielectric line junctions of arbitrary cross-section
PublicationThis paper is focused on the analysis of line junctions obtained as a cascade of dielectric and ferrite guides of arbitrary cross-section. The main application of such structures is nonreciprocal devices such as isolators, circulators, or phase shifters. The efficient finite element/mode-matching approach is proposed to the analysis of such structures. In this approach, thefiniteelementmethod is applied todetermine propagation...
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Autonomous Ship Utility Model Parameter Estimation Utilising Extended Kalman Filter
PublicationIn this paper, a problem of autonomous ship utility model identification for control purposes is considered. In particular, the problem is formulated in terms of model parameter estimation (one-step-ahead prediction). This is a complex task due to lack of measurements of the parameter values, their time-variability and structural uncertainty introduced by the available models. In this work, authors consider and compare two utility...
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A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification
PublicationThe article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...
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Interference between Land and Sea Logistics Systems. Multifunctional Building System Design Towards Autonomous Integrated Transport Infrastructure
PublicationThe research is focused on developing design theory towards efficient multifunctional facilities for logistics supply chains in the contemporary urban city structures. The development of modern systems based on autonomous transport creates new conditions for their management and generates an emerging need to define dedicated functional service structures. An important element of consideration also taken into account is the scenario...
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Tworzenie miejskości po 1990r., Geneza niemieckiej urbanistyki współczesnych założeń mieszkaniowych
PublicationArtykuł jest przyczyną do przypomnienia genezy współczesnej formy niemieckich miejskich struktur mieszkaniowych w kontekście zmian rozumienia ich wymiaru miejskości. Niemiecka myśl urbanistyczna łączy w sobie dwie wyraziste tradycje dwudziestego wieku - Gründerzeit i KlassischeModerne. Pozostaje jednak silnie otwarta na innowację generowaną nie tylko dzięki postępowi technicznemu, ale przede wszystkim poprzez planowanie interdyscyplinarne...
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Badania eksperymentalne i analiza numeryczna sklepień ceglanych. Wzmocnienie sklepień z wykorzystaniem struktur tensegrity.
PublicationCelem pracy jest opracowanie wzmocnienia zabytkowych sklepień murowych prętowo-cięgnowymi strukturami tensegrity. W tym celu przeanalizowano zagadnienia uszkodzeń, analizy oraz wzmacniania kopuł i sklepień murowych. W kolejnej części rozprawy przedstawiono prace badawczo-rozwojowe zakończone skutecznym wdrożeniem typoszeregu hal namiotowych o konstrukcji prętowo-cięgnowej typu tensegrity. Przeprowadzono badania dynamiczne oraz...
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Role patterns in IT projects teams - design of a selection module using fuzzy logic techniques
PublicationPresented paper introduces an approach based on usage of role patterns and modelling by the use of fuzzy logic tool for selection process with limitation to the area of IT projects environment. The article shows a concept of role patterns structures and their further usage in process of forming a fuzzy model dedicated to candidate assessment process support
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A 3D-FEM mesh technique for fast analysis of waveguide problems containing rotatable tuning elements
PublicationIn this paper a meshing technique for 3D Finite Element Method is presented. It allows for fast analysis and optimization of the waveguide structures, which contain rotatable tuning elements. In the proposed procedure a thin layer of varying cylindrical mesh buffer is introduced in order to reuse unchanged mesh and FEM matrices in the rest of the domain.
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Cost-efficient multi-objective design optimization of antennas in highly-dimensional parameter spaces
PublicationMulti-objective optimization of antenna structures in highly-dimensional parameter spaces is investigated. For expedited design, variable-fidelity EM simulations and domain patching algorithm are utilized. The results obtained for a monopole antenna with 13 geometry parameters are compared with surrogate-assisted optimization involving response surface approximation modeling.
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Method of selective fading as a educational tool to study the behaviour of prestressed concrete elements under excess loading
PublicationPrestressed structures are a key to realization of the boldest architectural ideas, characteristic feature of prestressed structure is better use of concrete material properties by insertion of internal forces. Learning about pre-stressed reinforced concrete structures is an integral part of Graduate Studies Program in construction engineering. Know-how of geometry change patterns in prestressed concrete elements under certain...
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Low-cost multi-objective optimization and experimental validation of UWB MIMO antenna
PublicationPurpose–The purpose of this paper is to validate methodologies for expedited multi-objective designoptimization of complex antenna structures both numerically and experimentally.Design/methodology/approach–The task of identifying the best possible trade-offs between theantenna size and its electrical performance is formulated as multi-objective optimization problem.Algorithmic frameworks are described for finding Pareto-optimal...
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Concrete versus green corridors in road planning. Gdansk case
PublicationThe aim of an article is to present the threats which may be caused by the construction of the transit road inside the city structure, and some mitigation measures aiming to eliminate or minimize environmental and landscape damages and social problems. Theoretical guidelines and conclusions will be followed by the example illustrating the problem. As an answer, some guidelines enabling sustainable road planning will be presented....
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Earthquake-Induced Pounding of Medium-to-High-Rise Base-Isolated Buildings
PublicationDuring earthquakes, out-of-phase vibrations in adjacent buildings with limited distance may cause pounding between them. In recent years, the use of seismic isolation has expanded considerably as an effective approach to reduce seismic damage. However, the isolated building experiences large displacements during earthquakes, and there is a possibility of collisions with adjacent structures. The research on earthquake-induced pounding...
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Analysis of pavement structure sensitivity to passage of oversized heavy duty vehicle in terms of bearing capacity
PublicationOversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor...
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How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies
PublicationIonic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation...
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An ANN-Based Approach for Prediction of Sufficient Seismic Gap between Adjacent Buildings Prone to Earthquake-Induced Pounding
PublicationEarthquake-induced structural pounding may cause major damages to structures, and therefore it should be prevented. This study is focused on using an artificial neural network (ANN) method to determine the sufficient seismic gap in order to avoid collisions between two adjacent buildings during seismic excitations. Six lumped mass models of structures with a different number of stories (from one to six) have been considered in...
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Emerging oxidized and defective phases in low-dimensional CrCl3
PublicationTwo-dimensional (2D) magnets such as chromium trihalides CrX3 (X ¼ I, Br, Cl) represent a frontier for spintronics applications and, in particular, CrCl3 has attracted research interest due its relative stability under ambient conditions without rapid degradation, as opposed to CrI3. Herein, mechanically exfoliated CrCl3 flakes are characterized at the atomic scale and the electronic structures of pristine, oxidized, and defective...