Duplex stainless steel (DSS) with a mixed ferrite–austenite structure is an advanced stainless-steel group with mechanical properties and corrosion resistance superior to those of single-phased steels. The dissimilar welding of DSS, between different grades of DSSs and with other material groups, is an active research area with huge importance for DSS applications. However, the complex composition of the alloying system may naturally lead to complicated phase structures, either in isolated form or as connected zones. This directly affects the structure integrity, weldability, corrosion resistance, and aesthetic appearance of stainless steels. The phase structure could also cause complex issues for developing microstructure-based models for different material groups. This work critically reviews and analyses recent developments and data on the dissimilar welding of DSSs, including welding between different groups, such as DSS, Super DSS, and Lean DSS, as well as welding of DSSs with carbon steels, high-strength steels, single-phased stainless steels, and other nonferrous alloys with/without filler alloys. Feature analysis is conducted on the key welding zones, and the main phases, including precipitation phases and intermetallic, primary, and secondary boundaries, are identified. Data analysis is conducted to classify the phase zones formed in the welding of different materials. A microstructural map of the location of intermetallic and secondary phases/zones in different weldments is presented and used to develop feature-based parametric finite element models. The effect of some key features of the phase zones/boundaries (e.g., martensite and intermetallic) on the structural integrity of the weldments is discussed.

Because of its benefits and digitization, smart materials technologies are becoming increasingly popular worldwide, and smart building construction is becoming a new development trend. These technologies are essential for achieving a competitive edge in the construction sector in the twenty-first century. It is anticipated that smart materials will dramatically improve functionality in the development of materials technology by acting like living systems and becoming a component of a structural system that is sensing its surroundings. This study examines the advantages of implementing smart materials technology in the building sector, even if there is less interest in this trend overall, especially in developing nations, than in traditional buildings. This paper also examines the increasingly apparent conventional division between materials science and architecture. It offers a critical examination of smart materials, shedding light on cutting-edge approaches and strategies that will influence architectural design and underscoring the close relationship between the two disciplines. The benefits of smart materials technologies are highlighted in this study, and they include safer, more secure operations, cost-effective maintenance, efficient energy use, employment creation, healthcare management, and real-time monitoring. As such, emerging economies must fully comprehend these advantages. This study emphasizes the advantages of smart materials technology for developing nations and makes the case for the necessity of a collaborative framework between academics and industry professionals in the building industry to advance understanding and successful implementation of this technology.

Introduction

Boron-doped nanocrystalline diamond (BDD) is an outstanding structure, and one of the best materials for high-sensitivity amperometric measurements. Nanocrystalline diamond structures show a high concentration of electrical charge carriers.

Amperometry is a widely used technique for studying the exocytosis of biological amines (dopamine, serotonin, noradrenaline, adrenaline, and histamine), and multielectrode array (MEA) systems have increased the efficiency and speed of amperometric studies.

In human, platelets are the most accessible cells to study the exocytosis of serotonin.

Methods

BDD-MEA fabrication utilizes several processes typical of microelectronics, here including chemical vapor deposition (CVD), optical lithography, metal evaporation, and reactive ion etching (RIE).

We detected amperometric recordings from the quantum release of serotonin from human platelets with boron-doped nanocrystalline diamond on MEA systems (BDD-MEA) of 16 microelectrodes. Our studies were carried out with devices on silicone matrices (BDD-on-silicon MEA)¹ and quartz substrates (BDD-on-quartz MEA)².

Results

Typical amperometric signals were obtained from the release and subsequent oxidation of serotonin molecules stored in platelet vesicles. We carried out and compared the release measurements both under basal conditions and after loading the platelets with 10 µM serotonin for 2 h. In this communication, we show different types of peaks registered in these studies and we present kinetics parameters obtained with both types of MEA systems (maximum oxidation current, spike width at half maximum, spike net charge, and ascending slope of spike).^1,2

Conclusions

BDD MEA devices have proven to be effective and biologically compatible in amperometric studies with live platelets. Here, we demonstrate their usefulness in studies of serotonin exocytosis from human platelets.

References.

¹ González Brito, R; Montenegro, P; Méndez, A; Carabelli, V; Tomagra, G; Shabgahi, R.E.; Pasquarelli, A.; Borges, R. Biosensors2023, 13, 86.

² González Brito, R; Montenegro, P; Méndez, A; Shabgahi, R.E.; Pasquarelli, A.; Borges, R. Biosensors2024, 14, 75.

New materials capable of storing and processing information at the level of a single molecule (atom) will contribute to the development of digital technologies. This type of molecules has to possess the property of bistability—the ability of molecules to exist in two stable spin states, for example, spin-crossover. In recent decades, there has been a growing interest in control over spin states of coordinative compounds based on Fe(III) cations because of their potential application in fields like molecular spintronics, memory and electronic devices, switches, and sensors [1].

The rational design of molecular building blocks allows researchers to manage the coordination sphere of the metal, and hence magnetic properties can be controlled [2]. Due to the possibility of wide functionalization, calix[4]arenes are extremely attractive for the design of pre-organized ligands. Moreover, the modification of calix[4]arene makes it possible to tune the structure of the complexes as well as to control their size and geometry. Disubstituted derivatives of calix[4]arenes allow the fine-tuning of the metal environment by varying the length of the alkyl spacer and the nature of the substituent in the coordinating fragment. It is particularly attractive to obtain salen-type ligands possessing N,O-coordinating chelate fragments.

In this work, we report on the synthesis of new Fe(III)-complexes based on polydentate lower rim disubstituted calix[4]arenes ligands, displaying a salen-type coordination pocket. The structures of prepared coordination compounds were studied by means of X-ray diffraction analysis, IR and 57Fe Mössbauer spectroscopy, and HR-ESI mass spectrometry. The structure–property correlation is also discussed.

1. Kaushik, S. Mehta, M. Das, S. Ghosh, S. Kamilya, A. Mondal. Chem. Com. 2023. 59(88), 13107-13124.
2. J. Harding, P. Harding, W. Phonsri. Coord. Chem. Rev. 2016, 313, 38-61.

The synthesis of new antitumor drugs is a promising direction in modern science. Nowadays, some thiazolopyrimidine derivatives are already known to exhibit different antitumor activities. Since the biological activities of racemate and pure enantiomers of many biologically active compounds may greatly differ from each other, the question of their separation, i.e., obtaining them in enantiopure form, is a pressing one.

Non-covalent interactions may be important for understanding the mechanism of drug action and can also be used in crystallization to separate racemic mixtures into pure enantiomers. Since a racemic mixture is formed during the synthesis of thiazolo[3,2-a]pyrimidine derivatives, the study of these derivatives in the crystalline phase is an essential problem.

This work is devoted to the synthesis and study of the supramolecular organization of new thiazolo[3,2-a]pyrimidine derivatives in the crystalline phase. The structure of all obtained compounds was characterized by IR, NMR ¹H and ¹³C spectroscopy, ESI-MS spectrometry, and SCXRD analysis.

The influence of the synthesized derivatives’ structure and the used solvent’s nature on the supramolecular motif of their organization in the crystal phase due to the presence of O-H...N and O-H...O type hydrogen bonds was established.

The majority of derivatives containing the o-vanillin fragment form racemic dimers. Derivatives containing a 4-hydroxybenzylidene fragment form zigzag homochiral chains. When derivatives containing a 2-hydroxybenzylidene fragment crystallize, bridging hydrogen O-H...N and O-H...O bonds are produced with a solvate molecule. It causes the formation of zigzag homochiral chains in the crystalline phase.

The crystallization of derivatives containing 2-methoxyphenyl with 2-hydroxybenzylidene and phenyl with 2-hydroxy-3-methoxybenzylidene moieties, respectively, from ethanol resulted in the formation of conglomerates.

The characterization of Fe-rich intermetallic compounds (Fe-IMCs) in DC casting billets of aluminium alloys is critical for understanding their downstream processing and the properties of the final components. The use of recycled aluminium scrap in the formulation of these alloys results in the accumulation of Fe and other elements and modifies the volume fraction, the size and the shape of these Fe-IMCs. Standard techniques, like optical or electronic microscopy, allow for 2D visualization and quantitative comparison but do not provide enough information about the real 3D morphology of the intermetallics or the connectivity between them. In this study, we have used X-ray computed tomography to evaluate the 3D features of the intermetallics in DC billets for an Al-Si-Mg alloy with different levels of Fe in the as-cast and homogenized conditions. The 3D analysis shows that increasing Fe in the alloy results in thicker, more elongated and more interconnected particles, while during homogenization, the particles become thinner and more rounded and fragmented. We also provide a detailed comparison between the 2D and 3D results. The use of real 3D morphology characteristics of the secondary phases is more accurate and will allow a better understanding of the solidification process forDC billets in industry, as well as the subsequent microstructure and the properties of the extruded components.

The long-awaited ferroelectric nematic LCs (NF) predicted more than a century ago were finally discovered in 2017, independently in two different materials: RM 734 [1] and DIO [2]. The two common features of these materials are (a) extremely high molecular dipole moment (µ ~10 D) and (b) giant dielectric permittivity (ε΄ ~ 10,000) in the ferroelectric N_F phase (Fig.1(a)). Two new compounds, WJ-16 and WJ-18, based on the chemical structure of DIO, were synthesized for a further enhancement of ferroelectricity by increasing the molecular dipole. As expected, both compounds exhibit extremely high dipole moments (10.6 D and 13.6 D respectively). Surprisingly the increase in dipole moment completely suppresses the ferroelectricity. However, giant permittivity was observed not only in nematic phase, but also in the SmA phases (see Fig.1(b)). After intensive study it is concluded that both samples are paraelectric rather than ferroelectric exhibiting colossal permittivity i.e. they belong to the class of super-paraelectrics (SPE) observed before only in the solid state. This it opens a new range of applications of liquid crystals as the working media for supercapacitors with the potential of using them in energy storage devices.

Acknowledgements: We thank the Irish Research Council for awarding the Government of Ireland PDF 2021, GOIPD/2021/858; and the CSC, China for a PhD scholarship.

References:

[1] R. J. Mandle et al, Phys. Chem. Chem. Phys. 19, 11429 (2017).

[2] H. Nishikawa et al., Adv. Mater. 29, 1702354 (2017).

[3] Neelam Yadav et al, J. Mol. Liq., 378, 121570 (2023).

The structural, microstructural, optical, and electrical properties of nanoceramic BaTi_1-xFe_xO_3-δ synthesized by sol--gel have been investigated. The X-ray diffraction analysis demonstrates that samples have a single-phase tetragonal structure with P4mm symmetry. This result was confirmed by the Rietveld method. Infrared spectroscopic analysis (FTIR) shows the presence of two bands at 490 Cm^-1 and 2358 Cm^-1 corresponding to T-O and C=O, respectively. On the other hand, scanning electron microscopy (SEM) results show that nanoceramics sintered at 1250°C have a spherical grain morphology. Grain size is small at X=0.02 and increases progressively thereafter. The UV--vis absorption spectrum confirms the influence of Fe concentration on the direct optical band gap of BaTi_1-xFe_xO_3-δ ceramics. The optical band gap shifts from 2.63 eV to 2.35 eV. Making this material a good candidate for solar photo-catalytic. There is an increase in Urbach energy as the Fe concentration increases from 0 to 0.4. On the other hand, the AC conductivity of the materials is subject to Joncher's law. The effect of Fe substitution concerns the decrease in conductivity at x=0.02 and then increases. The Cole--Cole complex impedance diagram was studied for the prepared samples. The compounds showed non-Debye-type dielectric relaxation, with a poor grain radius as Fe-doping increased.

Currently, hydrazones are promising building blocks for the creation of various supramolecular architectures, since they can undergo conformational and configuration changes under the influence of external conditions. Thus, from the point of view of supramolecular chemistry, the potential use of compounds containing a hydrazone functional group for the design of molecular switches, as well as for the creation of new materials, has been demonstrated.

This work is devoted to the synthesis and study of 2-arylhydrazone thiazolo[3,2-a]pyrimidine derivatives structures in the crystalline phase.

The obtained derivatives are characterized using a complex of physico-chemical (IR-, NMR ¹H- and ¹³C-spectroscopy, ESI-MS spectrometry, and X-ray diffraction) analyses.

It was confirmed that arylhydrazones are in the Z-isomer form in the crystalline phase. Additionally, it was established that non-covalent intramolecular and intermolecular interactions play the main role in supramolecular organization in crystals. So, the formation of hydrogen-, chalcogen-, π-π-bonded racemic dimers, and halogen-bonded homochiral chains was shown.

The structure of arylhydrazones containing halogen substituents in aryl fragments has also been studied. The embedding of a sterically inaccessible halogen substituent, blocked for the formation of intermolecular interactions, into one of two aryl fragments that switch off the action of structure-forming halogen bonding in one position and switch on in the second one, together leads to different self-assembly in the crystalline phase.

Thus, the synthesis and study of the supramolecular organization of 2-arylhydrazone thiazolo[3,2-a]pyrimidine derivatives in the solid phase were successfully carried out, and the possibility of implementing various supramolecular ensembles was discovered.

Ternary and quaternary silver chalcogenides are promising semiconductor materials for practical use that possess various valuable physical properties such as optical, electric, ferroelectric, ionic conductivity. Antimony chalcogenides are of interest to the research for thermoelectric properties and optical absorption suitable for thin-film solar cells. Our investigation combined these two directions in the quasi-ternary systems Ag₂S–C^III₂S₃–D^IVS₂ (C^III–Sb, As; D^IV–Ge, Sn) where three new quaternary sulfide compounds were found, Ag₁₁GeSb₃S₁₂, Ag₁₁SnSb₃S₁₂, and Ag₁₁SnAs₃S₁₂.

Alloys of the systems were synthesized by co-melting the elements at up to 1220 K, slow cooling to 500 K, annealing for 500 hrs followed by quenching. Ag₁₁GeSb₃S₁₂ forms at the intersection of AgSbS₂–Ag₈GeS₆ and Ag₃SbS₃–Ag₂GeS₃; Ag₁₁SnSb₃S₁₂ forms at the intersection of AgSbS₂–Ag₈SnS₆ and Ag₃SbS₃–Ag₂SnS₃; and Ag₁₁SnAs₃S₁₂ forms at the intersection of AgAsS₂–Ag₈SnS₆ and Ag₃AsS₃–Ag₂SnS₃. In all cases, the component ratio is 3:1. X-ray phase analysis and microstructure studies show that each compound has a modest homogeneity region of up to 5 mol.%.

The crystal structure of Ag₁₁GeSb₃S₁₂ was investigated by X-ray structural analysis. The diffraction dataset was recorded at a DROM 4-13 powder diffractometer, CuKα radiation, angle range 10°≤2Θ≤100°, scan step 0.02°, 10 s exposure in each point. The diffraction pattern of Ag₁₁GeSb₃S₁₂ was indexed in the cubic symmetry, space group I3m, lattice parameter а=0.54127(2) nm. Sulfur atoms form three-layer closest packing, the statistical mixture of Ag and Ge atoms occupies one half of the octahedral voids, and Sb atoms occupy one quarter of the tetrahedral voids.

Further investigation of the crystal structure of two other compounds as well as the study of optical absorption and electrophysical properties to quantify the prospects of these compounds as materials is pending.