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On Fast Multi-objective Optimization of Antenna Structures Using Pareto Front Triangulation and Inverse Surrogates
PublicationDesign of contemporary antenna systems is a challenging endeavor, where conceptual developments and initial parametric studies, interleaved with topology evolution, are followed by a meticulous adjustment of the structure dimensions. The latter is necessary to boost the antenna performance as much as possible, and often requires handling several and often conflicting objectives, pertinent to both electrical and field properties...
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Closer look into the structures of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water
PublicationIn recent years, deep eutectic solvents (DES) and it’s mixture with water have become more and more attention as green solvents used in chemistry. However, there are only a few theoretical studies on the mechanisms of pure DES and DES-water complex formation. Therefore, the structural properties of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water have been investigated by means of Molecular...
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Cost-Efficient EM-Driven Size Reduction of Antenna Structures by Multi-Fidelity Simulation Models
PublicationDesign of antenna systems for emerging application areas such as the Internet of Things (IoT), fifth generation wireless communications (5G), or remote sensing, is a challenging endeavor. In addition to meeting stringent performance specifications concerning electrical and field properties, the structure has to maintain small physical dimensions. The latter normally requires searching for trade-off solutions because miniaturization...
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SENSITIVITY ANALYSIS IN THE REHABILITATION OF HISTORIC TIMBER STRUCTURES ON THE EXAMPLES OF GREEK CATHOLIC CHURCHES IN POLISH SUBCARPATHIA
PublicationThis work concerns structural and sensitivity analysis of carpentry joints used in historic wooden buildings in south-eastern Poland and western Ukraine. These are primarily sacred buildings and the types of joints characteristic for this region are saddle notch and dovetail joints. Thus, in the study the authors focus on these types of corner log joints. Numerical models of the joints are defined and finite element simulations...
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Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
PublicationThe high molecular weight of chitin, as a biopolymer, challenges its extraction due to its insolubility in the solvents. Also, chitosan, as the N-deacetylated form of chitin, can be employed as a primary material for different industries. The low mechanical stability and poor plasticity of chitosan films, as a result of incompatible interaction between chitosan and the used solvent, have limited its industrialization. Deep eutectic...
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Developing Polycentricity to Shape Resilient Metropolitan Structures: The Case of the Gdansk–Gdynia–Sopot Metropolitan Area
PublicationMaking the metropolitan area resilient, in many cases, calls for amending its spatial structures. This may take various forms, including both reshaping the metropolitan core and redeveloping the entire regional network of cities and centres, making them part of a coherent structure. The latter strategy is associated with reinforcing secondary urban centres as well as shaping new connections between them. In this case, the term...
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Shaking table experimental study on pounding between adjacent structures founded on different soil types
PublicationThe aim of this study is to extensively investigate the effect of the soil type on the response of colliding structures based on shaking table experimental tests. Two single-storey models of steel buildings with different dynamic parameters were considered in this study. Three pounding scenarios were taken into account by applying different seismic gaps (0.5 cm, 1 cm and 1.5 cm as well as the no pounding case). First, the effect...
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Theoretical and experimental analysis of guided wave propagation in plate-like structures with sinusoidal thickness variations
PublicationGuided waves have attracted significant attention for non-destructive testing (NDT) and structural health monitoring (SHM) due to their ability to travel relatively long distances without significant energy loss combined with their sensitivity to even small defects. Therefore, they are commonly used in damage detection and localization applications. The main idea of incorporating guided waves in NDT and SHM is based on processing...
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On Accelerated Metaheuristic-Based Electromagnetic-Driven Design Optimization of Antenna Structures Using Response Features
PublicationDevelopment of present-day antenna systems is an intricate and multi-step process requiring, among others, meticulous tuning of designable (mainly geometry) parameters. Concerning the latter, the most reliable approach is rigorous numerical optimization, which tends to be re-source-intensive in terms of computing due to involving full-wave electromagnetic (EM) simu-lations. The cost-related issues are particularly pronounced whenever...
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Investigations of vortex-structures in granular bodies based on DEM and Helmholtz-Hodge flow field decomposition
PublicationArtykuł omawia wyniki numeryczne dotyczące struktur wirowych w materiałach granulowanych. Obliczenia wykonano dla stanu pasywnego przemieszczającej się sztywnej ścianki. W symulacjach wykorzystano metodę elementów dyskretnych i dekompozycję Helmholtza/Hodge’a pola prędkości. Struktury wirowe okazały się znakomitym prekursorem lokalizacji odkształceń stycznych w materiałach granulowanych.
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The propagation of the waves in the CTO S.A. towing tank
PublicationThe paper presents the results of research focused on the wave propagation in the CTO S.A. deepwater towing tank. In the scope of paper, the wavemaker transfer function was determined for regular waves, based on the Biésel Transfer Function and further for irregular waves, based on Hasselman model of nonlinear energy transfer. The phenomena: wave damping, wave breakdown and wave reflection, were measured, analyzed and mathematically...
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Elastoplastic law of Cosserat type in shell theory with drilling rotation
PublicationWithin the framework of six-parameter non-linear shell theory, with strain measures of the Cosserat type, we develop small-strain J2-type elastoplastic constitutive relations. The relations are obtained from the Cosserat plane stress relations assumed in each shell layer, by through-the-thickness integration employing the first-order shear theory. The formulation allows for unlimited translations and rotations. The constitutive...
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Model identification in urban structures revitalisation = Metody identyfikacji modeli stosowane w rewitalizacji budowli miejskich
PublicationW pracy zaprezentowano wybrane metody diagnostyki dynamicznej stosowane w identyfikacji modeli budowli zabytkowych. Do tego celu wykorzystano pomiary częstości i postaci drgań własnych budowli poddanych oddziaływaniom środowiskowych. Wykazano efektywność stosowanych metod identyfikacji parametrycznej modeli oraz identyfikacji uszkodzeń na przykładzie trzech budowli: dzwonnicy Archikatedry w Wilnie, wieży Twierdzy Wisłoujście w...
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Improved Consensus-Fragment Selection in Template-Assisted Prediction of Protein Structures with the UNRES Force Field in CASP13
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Evaluation of the scale-consistent UNRES force field in template-free prediction of protein structures in the CASP13 experiment
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Evaluation the P-Delta Effect on Collapse Capacity of Adjacent Structures Subjected to Far-field Ground Motions
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Graphitic Carbon Nitride and Titanium Dioxide Modified with 1 D and 2 D Carbon Structures for Photocatalysis
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Application of 3D Digital Image Correlation for Development and Validation of FEM Model of Self-Supporting Arch Structures
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Electric-field-induced quenching of photoluminescence in photoconductive organic thin film structures based on Eu3+ complexes
PublicationW pracy badano elektrycznopolowe wygaszenie fotoluminescencji w organicznych kompleksach europu Eu(III) rozdyspergowanych w matrycy poliwęglan: dwuamina TPD. W układzie z elektrodami Al/Al obserwowano wygaszenie fotoluminescencji wywołane dysocjacją ekscytonów. W układzie z elektrodami ITO(+)/Au(-) oprócz dysocjacji ekscytonów obserwowano również silne wygaszenie ekscytonów na ładunku elektrycznym wstrzykniętym do próbki. Analiza...
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Variable Data Structures and Customized Deep Learning Surrogates for Computationally Efficient and Reliable Characterization of Buried Objects
PublicationIn this study, in order to characterize the buried object via deep-learning-based surrogate modeling approach, 3-D full-wave electromagnetic simulations of a GPR model has been used. The task is to predict simultaneously and independent of each characteristic parameters of a buried object of several radii at different positions (depth and lateral position) in various dispersive subsurface media. This study has analyzed variable...
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Application of hybrid finite-difference mode-matching method to analysis of structures loaded with axially-symmetrical posts
PublicationW artykule przedstawiono nową metodę hybrydową do analizy układów falowodowych zawierających dowolne konfiguracje obiektów osiowo-symetrycznych. Metoda oparta jest na połączeniu metody różnic skończonych, metody dopasowania rodzajów oraz iteracyjnej procedury rozpraszania. W pracy przedstawiono badania zbieżności metody. Uzyskane wyniki numeryczne porównano z wynikami odniesienia. Duża zgodność wyników potwierdziła poprawność opracowanego...
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Syntheses, spectroscopic and structural properties of phenoxysilyl compounds: X-ray structures, FT-IR and DFT calculations
PublicationThe reaction of silicon disulfide with alkylphenols leads to tetraphenoxysilane, cyclodisilthiane and silanethiol. The products of the reaction of silicon disulfide with phenols are characterized by FT-IR, NMR, X-ray diffraction and DFT calculations. The intramolecular interactions in the compounds are mainly XH---π (X = C, S) whereas the intermolecular interactions are either very weak CH---π/CH---O contacts found in aryloxysilane...
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Self-Association of Amphotericin B: Spontaneous Formation of Molecular Structures Responsible for the Toxic Side Effects of the Antibiotic
PublicationAmphotericin B (AmB) is a lifesaving antibiotic used to treat deep-seated mycotic infections. Both the pharmaceutical activity and highly toxic side effects of the drug rely on its interaction with biomembranes, which is governed by the molecular organization of AmB. In the present work we present detailed analysis of self-assembly of AmB molecules in different environments, interesting from the physiological standpoint, based...
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Accuracy improvement of the prestressed concrete structures precise geometry assessment by use of bubble micro-sampling algorithm
PublicationPrestressed concrete structures are well-known technology for a vast period, but nevertheless, this very technology is a leading solution, currently used in construction industry. Prestressed concrete structures have a huge advantage over conventional methods because it uses the properties of concrete in a very efficient way. The main idea behind this technology is to introduce into the cross-section of the structure, the internal...
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Determination of Vehicles Load Equivalency Factors for Polish Catalogue of Typical Flexible and Semi-rigid Pavement Structures
PublicationThe new Polish Catalog of Typical Flexible and Semi-rigid Pavement Structures was introduced to use in practice in 2014. Much of works were focused on actualization of vehicles load equivalency factors. For this purpose data delivered from weigh-inmotion were analyzed. Four methods of determination of load equivalency factors for pavement structure design were compared. The analysis showed that fourth power equation, AASHTO 1993...
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Recent Achievements in Constitutive Equations of Laminates and Functionally Graded Structures Formulated in the Resultant Nonlinear Shell Theory
PublicationThe development of constitutive equations formulated in the resultant nonlinear shell theory is presented. The specific features of the present shell theory are drilling rotation naturally included in the formulation and asymmetric measures of strains and stress resultants. The special attention in the chapter is given to recent achievements: progressive failure analysis of laminated shells and elastoplastic constitutive relation...
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Medium-sized cyclic bis(anisylphosphonothioyl)- disulfanes and their corresponding cyclic sulfane-structures and most characteristic reactions
PublicationCyclic 8-, 9-, 10-, and 12-membered bis(anisylphosphonothioyl)disulfanes were synthesized. Next, structurally related 7 to 9-membered cis and trans sulfanes were isolated as a result of sulfur atom extrusion from the parent cyclic disulfanes. The results of the desulfurization of the disulfanes were compared to the results obtained for desulfurization of the respective bis(anisylphosphodithioates). Cyclic disulfanes predominantly...
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A Novel Trust-Region-Based Algorithm with Flexible Jacobian Updates for Expedited Optimization of High-Frequency Structures
PublicationSimulation-driven design closure is mandatory in the design of contemporary high-frequency components. It aims at improving the selected performance figures through adjustment of the structure’s geometry (and/or material) parameters. The computational cost of this process when employing numerical optimization is often prohibitively high, which is a strong motivation for the development of more efficient methods. This is especially...
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublicationThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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Evaluation the P-Delta Effect on Collapse Capacity of Adjacent Structures Subjected to Far-field Ground Motions
PublicationIn urban areas, adjacent structures can be seen in any insufficient distance from each other, because of economic reasons and refusal of acquired minimum separation distance according to seismic previsions. Collapse capacity assessment of structures is one of the important objectives of performance-based seismic engineering. The purpose of this study is to consider the pounding phenomenon and P-Delta effect in seismic collapse...
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Architectural Space of Ideas in the Author’s Structures Presented at the Fire Painted Images Art Festival: A Case Study
PublicationThe article is aimed to discuss the place of architecture in the space of ideas. The present work discusses a specific place, the Zaspa housing estate in Gdańsk, and refers to a specific person, namely, the author of artistic installations tem- porarily exhibited in the Zaspa housing estate. Also, the wider context of the specific situations in which the exhibitions were...
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Experiment-aided virtual prototyping to minimize tool-workpiece vibration during boring of large-sized structures
PublicationThe paper presents the author's method of solving the problems of vi-bration suppression during boring of large-sized workpieces by means of an in-novative method of adjusting the rotational speed of the boring bar. It consists in selecting the spindle speed in accordance with the results of the cutting process simulation. The method includes identification of the model of the finite element method of the boring bar. The Root Mean...
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Reliable data-driven modeling of high-frequency structures by means of nested kriging with enhanced design of experiments
PublicationData-driven (or approximation) surrogate models have been gaining popularity in many areas of engineering and science, including high-frequency electronics. They are attractive as a way of alleviating the difficulties pertinent to high computational cost of evaluating full-wave electromagnetic (EM) simulation models of microwave, antenna, and integrated photonic components and devices. Carrying out design tasks that involve massive...
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DEM investigations of two-dimensional granular vortex- and anti-vortex- structures during plane strain compression.
PublicationDEM investigations of two-dimensional granular vortex- and anti-vortex- structures during plane strain compression.
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On modelling and non-linear elasto-plastic analysis of thin shells with deformable junctions
PublicationThe undeformed base surface of the irregular thin shell is modelled by the union of a finite number of regular smooth surface elements joined together along spatial curvilinear surface edges. The equilibrium conditions are formulated by postulating an appropriate form of the principle of virtual work, where also deformability of shell junctions is taken into account. The PVW is then discretised by C1 finite elements and the incremental-iterative...
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Modeling of the K and L x-ray line structures for molybdenum ions in warm dense Z-pinch plasma
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Distributed System for Monitoring of the Large Scale Infrastructure Structures Based on Analysis of Changes of its Static and Dynamic Properties
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Functional Bi2O3/Gd2O3 Silica-Coated Structures for Improvement of Early Age and Radiation Shielding Performance of Cement Pastes
PublicationThis study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated...
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Application of 3D digital image correlation for development and validation of FEM model of self-supporting metal plates structures
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Reaction of methanol ligated manganese(II) silanethiolate with pyridine related ligands - different structures of complexes with MnNO2S2 kernel
PublicationReakcja silanotiolanu manganu(II) z pirydyną i jej metylowymi pochodnymi prowadzi do uzyskania heteroleptycznych kompleksów o tym samym rdzeniu MnNO2S2, ale o różnym typie strukturalnym. W przypadku posłużenia się pirydyną i 2-metylopirydyną uzyskano układy zawierające dwie cząsteczki alkoholu przykoordynowane do centrum metalicznego. Z kolei w przypadku 3- i 4-metylopirydyny funkcję S,O-donorów spełniają reszty silanotiolanowe.
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Consequences of neglecting the appropriate safety conditions of structures exposed to seismic excitations - damage examples after the Kaliningrad earthquake
PublicationW artykule przedstawiono przykłady uszkodzeń budowli znajdujących się w złym stanie technicznym, które powstały w wyniku trzęsienia ziemi o epicentrum w Obwodzie Kaliningradzkim. Przykłady te jednoznacznie pokazują, iż zaniedbywanie stanu technicznego konstrukcji narażonych na wstrząsy sejsmiczne może prowadzić do poważnych konsekwencji powodując znaczne straty materialne lub ofiary śmiertelne.
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On the effectiveness of Ni alloy-bronze composite lattice structures used in slide bearings operated under heavy loads
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Application of Shape Memory Alloys in Retrofitting of Masonry and Heritage Structures Based on Their Vulnerability Revealed in the Bam 2003 Earthquake
PublicationFor decades, one of the most critical considerations of civil engineers has been the construction of structures that can sufficiently resist earthquakes. However, in many parts of the globe, ancient and contemporary buildings were constructed without regard for engineering; thus, there is a rising necessity to adapt existing structures to avoid accidents and preserve historical artefacts. There are various techniques for retrofitting...
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Dynamic range comparison of voltage-mode and current-mode state-space Gm-Cbiquad filters in reciprocal structures
PublicationW pracy dokonano porównania zakresu dynamicznego bikwadratowych filtrówGm-C zmiennych stanu, których struktury układowe oparte są na zasadzie tran-sformacji układu dołączonego. Przeprowadzono rozważania teoretyczne w wynikuktórych określono ogóne formuły zakresu dynamicznego dla klasy filtrów Gm-Ctrybu napięciowego i prądowego. Weryfikacja rezultatów teoretycznych byłazrealizowana za pomocą symulatora SPICE.
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Formation, crystal and molecular structures of heteroleptic zinc(II) tri-tert-butoxysilanethiolates with ZnNO2S2 and ZnN2S2 coordination pattern.
PublicationZsyntetyzowano pięć tri-tert-butoksysilanotiolanów cynku zawierających jako dodatkowe ligandy heterocykliczne, zasady azotowe. Wzór ogólny tych kompleksów to Zn(SSi(OBut)3)2L, gdzie L=alfa-pikolina, 2,4-lutydyna, N-metyloimidazol lub Zn(SSiOBut)3)2L2, gdzie L=N-metyloimidazol lub pirydyna. Określono strukturę krystaliczną otrzymanych związków oraz zmierzono widma IR i NMR.
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The correlation between impact energy and the meters of hardening of extra high strength steels for ship and offshore welded structures.
PublicationUdowodniono tezę, że można wyznaczyć wystarczająco dokładne dla praktyki projektowania i budowy konstrukcji okrętowych i oceanotechnicznych związki ilościowe odbiorczych właściwości mechanicznych i mikrostruktury blach grubych kategorii 420¸690 oraz ich złączy spawanych. Uzyskane w pracy związki mierników umocnienia (cementytem, roztworowe, wydzieleniowe, wymiarem ziarna ferrytu) z odbiorczymi właściwościami mechanicznymi (Rm,...
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Model Management for Low-Computational-Budget Simulation-Based Optimization of Antenna Structures Using Nature-Inspired Algorithms
PublicationThe primary objective of this study is investigation of the possibilities of accelerating nature-inspired optimization of antenna structures using multi-fidelity EM simulation models. The primary methodology developed to achieve acceleration is a model management scheme which the level of EM simulation fidelity using two criteria: the convergence status of the optimization algorithm, and relative quality of the individual designs...
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Enhanced electrochemical activity of boron-doped nanocarbon functionalized reticulated vitreous carbon structures for water treatment applications
PublicationAn extraordinary charge transfer kinetics and chemical stability make a boron-doped diamond (BDD) a prom- ising material for electrochemical applications including wastewater treatment. Yet, with flat geometrical sur- faces its scaling options are limited. In this study, the reticulated Vitreous Carbon (RVC) served as a substrate for boron-doped diamondized nanocarbons (BDNC) film growth resulting with complex heterogeneity carbon structures...
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Controlling nodal displacement of pantographic structures using matrix condensation and interior-point optimization: A numerical and experimental study
PublicationThis study presents an innovative approach for the precise control of nodal displacements in pantographic structures. The method is founded on the Matrix Condensation of Force Method, seamlessly integrated with an Interior Point Optimization algorithm. This combination offers a unique advantage by allowing users to manipulate displaced nodes within a defined coordination domain. Furthermore, this approach introduces the Interior...
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Syntheses, structures, and chiroptical and magnetic properties of chiral clusters built from Schiff bases: a novel [MnIIMnIII6NaI2] core
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