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Highlights: Synergistic passivation mechanism of the dual functional compound of potassium bromide for metal halide perovskite films, that is through chemical bonding and physical screening towards the various types of defects. Metal-ion additives can simultaneously passivate the defects of halide vacancies with bromine anions and dangling bond defects with metal cations. Achieve the maximum external quantum efficiency of ~21% and maximum luminance of ~60,000 cd m−2. Metal halide perovskites, particularly the quasi-two-dimensional perovskite subclass, have exhibited considerable potential for next-generation electroluminescent materials for lighting and display. Nevertheless, the presence of defects within these perovskites has a substantial influence on the emission efficiency and durability of the devices. In this study, we revealed a synergistic passivation mechanism on perovskite films by using a dual-functional compound of potassium bromide. The dual functional potassium bromide on the one hand can passivate the defects of halide vacancies with bromine anions and, on the other hand, can screen the charged defects at the grain boundaries with potassium cations. This approach effectively reduces the probability of carriers quenching resulting from charged defects capture and consequently enhances the radiative recombination efficiency of perovskite thin films, leading to a significant enhancement of photoluminescence quantum yield to near-unity values (95%). Meanwhile, the potassium bromide treatment promoted the growth of homogeneous and smooth film, facilitating the charge carrier injection in the devices. Consequently, the perovskite light-emitting diodes based on this strategy achieve a maximum external quantum efficiency of ~ 21% and maximum luminance of ~ 60,000 cd m−2. This work provides a deeper insight into the passivation mechanism of ionic compound additives in perovskite with the solution method. [ABSTRACT FROM AUTHOR]

Molecular junctions, which involve sandwiching molecular structures between electrodes, play a crucial role in molecular electronics. Recent advances in this field have revealed the vital role of organometallic chemistry in the investigation of molecular junctions, which has added to their well-known contributions to catalysis and materials chemistry. This review summarizes the recent examples of organometallic chemistry applications in molecular junctions, which can be categorized into three types, i.e., class I encompassing molecular junctions with bridging organometallic complexes, class II involving molecular junctions with covalent and noncovalent metal electrode-carbon bonds, and class III comprising organometallic reactions within molecular junctions. [ABSTRACT FROM AUTHOR]

The fangs, jaws, and mandibles of marine invertebrates such as Chiton and Glycera show excellent mechanical properties, which are mostly contributed to the interactions between metal (Fe, Cu, Zn, etc.) and oxygen-containing functional groups in proteins. Inspired by these load-bearing skeletal biomaterials, we improved tensile strength and toughness of graphene films through bridging graphene oxide (GO) nanosheets by metal ions. By optimizing the metal coordination form and density of cross-linking network. We revealed the relationship between mechanical properties and the unique spatial geometry of the GO nanosheets bridged by different valence metal ions. The results demonstrated that the divalent metal ions form tetrahedral geometry with carboxylate groups on the edges of the GO nanosheets, and the bond energy is relatively low, which is helpful for improving the toughness of resultant graphene films. While the trivalent metal ions are easily to form octahedral geometry with the GO nanosheets with higher bond energy, which is better for enhancing the tensile strength of graphene films. After reduction, the reduced GO (rGO) film bridged by divalent metal ions shows 43% improvement in toughness, while the rGO film bridged by trivalent metal ions shows 64% improvement in tensile strength. Our work reveals the mechanism of metal coordination bond energy and spatial geometry to improve the mechanical properties of graphene films, which lays a theoretical foundation for improving the tensile strength and toughness of resultant graphene films, and provides an avenue for fabricating high-performance graphene films and other two-dimensional nanocomposites. [ABSTRACT FROM AUTHOR]

Carbolong complexes are one of the primary types of metallaaromatics, and they include metallapentalynes and metallapentalenes. A series of 7C-10C and 12C-carbolong complexes with planar ligand skeletons respectively containing 7-10 and 12 carbon atoms in their backbones, have been previously reported. Herein, two classes of strained substances, metallabenzyne-fused metallapentalenes and metallabenzene-fused metallapentalynes, were prepared, both representing 11C-carbolong complexes with a planar carbon-chain ligand. Furthermore, the former type is also the carbolong derivatives containing a metallabenzyne skeleton, another primary metallaaromatic framework. Metallabenzyne-fused metallapentalenes show versatile reactivities, and the most interesting one is the metal carbyne bond shift from a 6-membered to a more strained 5-membered ring, affording the above-mentioned metallabenzene-fused metallapentalyne. This work makes carbolong chemistry more complete, and provides a method to achieve metallabenzynes, which is anticipated to concurrently advance the development of these two types of metallaaromatics. 7C-10C and 12C-carbolong complexes with planar ligand skeletons containing 7-10 and 12 carbon atoms have been previously reported but 11C-carbolong complexes with a planar carbon-chain ligand are elusive. Here, the authors prepare metallabenzyne-fused metallapentalenes and metallabenzene-fused metallapentalynes, both representing 11C-carbolong complexes with a planar carbon-chain ligand [ABSTRACT FROM AUTHOR]

The distribution of reinforcements and interfacial bonding state with the metal matrix are crucial factors in achieving excellent comprehensive mechanical properties for aluminum (Al) matrix composites. Normally, after heat treatment, graphene nanosheets (GNSs)/Al composites experience a significant loss of strength. Here, better performance of GNS/Al was explored with a hybrid strategy by introducing 0.9 vol.% silicon carbide nanoparticles (SiCnp) into the composite. Pre-ball milling of Al powders and 0.9 vol.% SiCnp gained Al flakes that provided a large dispersion area for 3.0 vol.% GNS during the shift speed ball milling process, leading to uniformly dispersed GNS for both as-sintered and as-extruded (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al. High-temperature heat treatment at 600 °C for 60 min was performed on the as-extruded composite, giving rise to intragranular distribution of SiCnp due to recrystallization and grain growth of the Al matrix. Meanwhile, nanoscale Al4C3, which can act as an additional reinforcing nanoparticle, was generated because of an appropriate interfacial reaction between GNS and Al. The intragranular distribution of both nanoparticles improves the Al matrix continuity of composites and plays a key role in ensuring the plasticity of composites. As a result, the work hardening ability of the heat-treated hybrid (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al composite was well improved, and the tensile elongation increased by 42.7% with little loss of the strength. The present work provides a new strategy in achieving coordination on strength–plasticity of Al matrix composites. [ABSTRACT FROM AUTHOR]

Self-healing polydimethylsiloxane (PDMS) has garnered significant attention due to its potential applications across various fields. In this study, a functionalized modification of PDMS containing di-aminos was initially conducted using 2,6-pyridinedicarbonyl chloride to synthesize pyridine-PDMS (Py-PDMS). Subsequently, rare earth metal europium ions (Eu3+) were incorporated into Py-PDMS. Due to the coordination interaction between Eu3+ and organic ligands, a coordination cross-linking network was created within the Py-PDMS matrix, resulting in the fabrication of Eu3+-Py-PDMS elastomer. At a molar ratio of Eu3+ to ligands of 1:1, the tensile strength of Eu3+-Py-PDMS reached 1.4 MPa, with a fracture elongation of 824%. Due to the dynamic reversibility of coordination bonds, Eu3+-Py-PDMS with a metal-to-ligand molar ratio of 1:2 exhibited varying self-healing efficiencies at different temperatures. Notably, after 4 h of repair at 60 °C, its self-healing efficiency reached nearly 100%. Furthermore, the gas barrier properties of Eu3+-Py-PDMS with a molar ratio of 1:1 was improved compared with that of Eu3+-Py-PDMS with a molar ratio of 1:1. This study provides an effective strategy for the design and fabrication of PDMS with high mechanical strength, high gas barrier properties, and exceptional self-healing efficiency. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) is a traditional chemical known for its chemical stability and mechanical performance. Inspired by the similarity between the formation and breakage of chemical coordination bonds and the energy storage and release of muscle fibers, muscle‐like electrostatically spun fibers with acid‐responsive energy storage and release were prepared by introducing bio‐inspired elastic energy storage groups and bio‐active degradation groups (PU‐BPY‐Fe) in the main chain of PU, taking advantage of the good mechanical properties of PU. The fabricated electrospinning film PU‐BPY‐Fe can respond to external stimulation, which generated high strain (32 MPa), stretch of 206%, outperforming the nanofiber membrane before stimulation, similar and even higher than the biological muscles. The variable mechanical properties and elastic energy storage capacity of PU‐BPY‐Fe were attributed to the reversible hydrogen bonding and the destabilization of metal coordination bonds (Fe3+ to Fe2+) within the material under acidic stimulation. Cytotoxicity testing of the synthesized fibers indicated a degree of biocompatibility, suggesting potential for in vivo applications. This method of storing and releasing elastic energy was demonstrated and has endowed the PU‐BPY‐Fe with stimuli‐responsibility and muscle‐like mechanical properties, which may inspire the design of soft muscles materials for robots and tissue engineering applications. [ABSTRACT FROM AUTHOR]

To delve into the microscopic property variations of the ConMoP(n = 1 ~ 5) cluster, this study employs density functional theory at the B3LYP/def2‐TZVP quantum chemistry level. The paper conducts a comprehensive theoretical analysis of the clusters, examining parameters such as bond lengths, bond angles, electronic localization function (ELF), interaction region indicator function (IRI), independent gradient model based on the Hirshfeld partition, deformation density, electronic space range, chemical hardness and softness, polarizability, and dipole moment. The optimization process reveals 16 stable configurations for the ConMoP(n = 1 ~ 5) cluster, predominantly taking on a steric form. As the cluster size increases, the electronic delocalization of Co atoms intensifies, while the electronic properties of Mo atoms remain relatively stable. Notably, P atoms maintain a high degree of electronic delocalization. The interatomic forces within the clusters predominantly exhibit covalent bonding, with no evident repulsive effects observed between atoms. The bonding between metal atoms in the clusters leans toward a preference for covalent interaction. The degree of dispersion in the clusters increases with their growth, particularly evident in configuration 5‐a, which displays a broader spatial distribution. Configuration 3‐a demonstrates the most favorable activity, showcasing a relatively stable structure. Overall, configuration 3‐a emerges as a focal point for catalytic reactions. This article provides a more comprehensive analysis of the ConMoP(n = 1 ~ 5) cluster, yielding diverse results and enhancing the theoretical understanding of this cluster. [ABSTRACT FROM AUTHOR]

In practical applications, C/C composites often need to be joined to metals. However, one major issue that needs to be addressed is the high residual stress in heterogeneous joints. To enhance the interfacial bonding between C/C composites and metals, this study has utilized ultrafast high-temperature shock (UHS) to selectively oxide C/C composites, resulting in the formation of a zig-zag microstructure on the surface. By achieving an extremely short processing time of only 30 s, the efficiency of oxidation process has been improved by several hundred times, leading to a reduction in the rate of weight loss to less than 3%. After brazing, the filler penetration zone is formed, which effectively increases the bonding area between filler and C/C composites, improves pinning effect and alleviates residual stress. Notably, the joints demonstrate a shear strength of 25.3 MPa, which is 1.9 times higher compared to the original joints without employing oxidation process. [ABSTRACT FROM AUTHOR]

The study investigates the deep drawing process for bimetallic sheets formed by bonding dissimilar metals (AA1100 aluminium alloy and C36000 brass) with epoxy-based adhesive. Experimental exploration of process parameters, including blank diameter, stacking sequence, lubrication, and strain rate, was conducted to analyse their impact on load–displacement behaviour and thickness strain distribution. Additionally, the study assessed fracture susceptibility, material flow characteristics (tearing and wrinkling), and the requisite drawing force for the bonded specimens. Results indicate enhanced formability and mechanical properties in bonded sheets compared to individual metal sheets, demonstrating the potential advantages of this approach. The bonded sheets demonstrated improved formability and mechanical properties compared to individual metals. Notably, the maximum drawing force for the bonded sheet (170 mm diameter) significantly increased to 24.2 kN, surpassing individual sheets by 69.85% for AA1100 and 40.54% for C36000. The analysis identified a vulnerable region (12–15 mm from the centre) under maximum risk of failure and consistent deformation patterns in samples with varying diameters and lubrication, providing valuable insights into the behaviour of bonded bimetallic sheets in deep drawing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Orofacial Orthopedics/Fortschritte der Kieferorthopadie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, we report the first set of pincer complexes 1 and 2 with the general formula [Ru(CNC)(PPh3)2Cl]Cl having a protic- and classical-NHC in the same molecule and nearly identical environments. Deprotonation of the protic-NHC complex 2 with one equivalent of base leads to the formation of anionic-NHC complex 2′. These complexes allow a direct comparison of protic- and anionic-NHCs with the classical-NHC ligand. A comparison of the molecular structure indicated that the metal carbene bond length trend is anionic-NHC > protic-NHC > classical-NHC. The electrochemical investigation revealed the electron donation tendency is classical-NHC > protic-NHC and anionic-NHC > protic-NHC. Cooperation between the metal and the ligand is indicated by the reaction of 2′ with H2 gas at 1 atm pressure and 110 °C to give the Ru-hydride complex 3. [ABSTRACT FROM AUTHOR]

Solid‐state lithium metal batteries (SSLMBs) have gained extensive attraction as one kind of next‐generation energy storage device. However, the drawbacks of flammability, low mechanical strength, and low ionic conductivity limit the further development of solid‐state polymer electrolytes (SPEs). In this work, a reactive flame‐retardant unit into the polymer framework via covalent bonding to create a nonflammable and stretchable polyurethane‐based SPEs is introduced. Meanwhile, the mechanical strength of the polymer backbone is increased by grafting a rigid benzene ring unit, which remarkably suppresses the lithium‐dendrite growth. As a result, these inflammable SPEs do not burn after contact with flames for 6 s. Furthermore, the obtained SPE expands the electrochemical stability window up to 5.1 V. Small monomers containing bromine decompose on the surface of lithium metal creating a LiBr riched solid electrolyte interface (SEI). Li|SPEs|Li symmetric battery offers a stable cycling life for more than 2100 h at 0.2 mA cm−2 and 0.2 mAh cm−2. The LiNi0.6Co0.2Mn0.2O2|SPEs|Li cell equipped with the integrated cathode delivers a 142.1 mAh g−1 capacity after 330 cycles at 0.3 C with 85.2% capacity retention. [ABSTRACT FROM AUTHOR]

The hot corrosion experiments of René N5 alloy coated with three different NiCrAlY metal bonding layers are carried out, that the layers are prepared by different methods (APS, HVAF and MIP). Compared with bare René N5 alloy samples, the hot corrosion resistance of coated samples is improved. It can be attributed to the small internal stress of the surface oxide layer on the coating sample, which is difficult to spall, reducing the degree of hot corrosion reaction. The hot corrosion resistance of NiCrAlY layers is MIP > HVAF > APS, which is positively positively related to the density of layers, because the influence of element diffusion in the process of hot corrosion is effectively slowed down. [ABSTRACT FROM AUTHOR]

The structure and stability of noble gas (Ng) bound [NHCM]+ complexes (M = Cu, Ag, and Au) were investigated using Quantum chemical calculations. Dissociation energies, enthalpy, and free energy changes were computed to comprehend the stability of these Ng‐bonded complexes. The nature of interactions associated to the bonding between metal and noble gas atoms was studied through the computation of electron density‐based descriptors. Detailed electronic structure study revealed electron donation from the noble gas atoms towards the metal center, resulting in the formation of dative bonds. [ABSTRACT FROM AUTHOR]

Adducts between OsO4 and Lewis bases exert a role in important oxidation processes such as epoxidation and dihydroxylation. It has been shown that the attractive interaction driving the formation of these adducts is a σ‐hole bond involving the metal as the electrophilic species; the term Osme Bond (OmB) was proposed for designating it. Here some new adducts between OsO4 and various bases have been characterized through single crystal x‐ray diffraction (XRD) and computational studies (density functional theory, DFT), confirming the existence of a robust correlation between σ‐hole interaction energy and deformation of the tetrahedral geometry of OsO4. Also, some adducts formed by RuO4 with nucleophiles were investigated computationally. [ABSTRACT FROM AUTHOR]

Aim: In this, in vitro study's objective is to assess the shear bond strength (SBS) of metal and ceramic orthodontic brackets that have been adhered to enamel using a conventional acid etch/primer and self-etching primer (SEP) adhesive method. Materials and Methods: One hundred excised human premolars were bonded on brackets and were divided into group 1 -Metal brackets were bonded on teeth and group 2 -Ceramic brackets were bonded on teeth. These two groups were further subdivided: subgroup 1a - 25 metal brackets bonded using conventional acid etch/primer adhesive system, subgroup 1b - 25 metal brackets bonded using SEP, subgroup 2a - 25 ceramic brackets bonded using conventional acid etch/primer adhesive system, and subgroup 2b - 25 ceramic brackets bonded using SEP; brackets were debonded using a computerized Instron universal testing machine. Results: The mean value of SBS of metal and ceramic brackets bonded using conventional acid etch/primer adhesive systems had higher SBS than those bonded using SEP. SBS ranged from 7.95 to 12.24 MPa which was in the acceptable clinical range. Conclusion: SBS values of all four subgroups exceeded the range of 6-8 MPa observed to be acceptable for routine clinical use. [ABSTRACT FROM AUTHOR]

Micro‐LED, as one of the most promising advanced display technologies, has attracted increasing research interest from academia and display industry. With the outstanding performance in brightness, lifetime, and contrast, Micro‐LED display shows tremendous potential for applications in various electronic terminals. The bonding between Micro‐LED and backplane is the key technology that affects the industrialization of Micro‐LED display at present. The common bonding technology can be classified as metal bonding and ACF bonding. Metal bonding has the advantages of low cost and high bonding strength. However, the bonding yield is affected by the difficulties of thermal mismatch and short circuit. In order to solve these difficulties, we developed a bonding process based on Non‐Conductive Paste (NCP). That is, the Micro‐LED transfer onto the backplane with a lay of NCP, then realizing the conductivity between the Micro‐LED and the backplane by thermocompression bonding. In this paper, we applied this technology in 180 × 160 pixels full‐color Micro‐LED display, and achieved more than 99.99% bonding yield by testing the NCP material characteristics, temperature and pressure. [ABSTRACT FROM AUTHOR]

Micro‐LED is considered as the new generation of display with the long‐lifetime, high contrast and brightness, splicing capability, etc. Mass transfer is the bottleneck that limits the manufacturing of Micro‐LED display at large volume, due to factors such as laser‐ lift off, pick‐up, metal bonding, and so on. Metal bonding between the Micro‐LED chip and the substrate is one of the most important impactors to the light‐up yield. To solve the key thermal mismatch issue between the backplane and Micro‐LED donor during heating, the laser‐assisted bonding process could be a viable solution. We present a study in metallic element Au/Sn with high productivity, capability and low cost, as well as good thermal and electrical conductivity, excellent bonding strength, and low sensitivity to surface roughness. The result is presented in a 62× 78 pixels full color Micro‐LED display, with reliable metal electrical connection between microscale LED devices and the backplane that can be achieved under 250℃ without any damage to the backplane. In conclusion, the micro morphology and formation mechanism of different alloy phase compositions of welded metal elements have been thoroughly studied, and a feasible technological methodology has been developed for the upcoming mass production of Micro‐LED display modules. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been employed in many studies recently because of their stability, porosity, and high surface area. Although zeolitic imidazole frameworks (ZIF-8) have many advantages among MOFs, they have disadvantages such as low activity, conductivity, and reusability depending on the application. To overcome these drawbacks, Fe3O4 and a mixture of Fe3O4 and MnO2 were added into the structure of ZIF-8. The SEM and STEM analysis of the synthesized materials showed that the polyhedral structure of ZIF-8 was hardly affected by the integration of metal oxides into the structure. FTIR and XPS results showed the presence of peaks arising from organic ligands and metal bonds with ZIF-8 in metal oxide/ZIF-8. Addition of Fe3O4 and Fe3O4–MnO2 to structure of ZIF-8 decreased the surface area of ZIF-8 with the formation of mesopores and accumulation of metal oxide particles in pores. When the synthesized metal oxide/ZIF-8 samples were tested in supercapacitor applications, MnO2/ZIF-8 electrode showed the highest specific capacitance. In addition, the presence of metal oxides in the ZIF-8 improved conductivity of the material. Based on the properties of metal oxide/ZIF-8 composites, the materials have also a potential for applications such as gas storage, adsorption, catalysts, and membranes. [ABSTRACT FROM AUTHOR]

This work aims at improving the medium- and low-temperature strength of Al2O3-C unfired slide plate materials. Sucrose, nickel nitrate hexahydrate, ethyl orthosilicate and oxalic acid aqueous solution with the mass ratio of 1:0. 15:2. 7:0 0.03 were added to ethanol aqueous solution in turn, and dried at 110 °C for 18 h, obtaining SiC polymer precursor. Then, tabular corundum, α-Al2O3 micropowder and flake graphite were used as the main raw materials, added with the SiC polymer precursor and Zn powder, pressed at 150 MPa into green bodies of 150 mm x25 mm x25 mm, cured at 180 °C for 24 h, and then heat treated at 600, 800, 1 000, 1 200 and 1 400 °C for 3 h under carbon embedded conditions. The effects of the SiC polymer precursor and Zn powder on the properties of Al2O3-C materials were studied. The results show that the Al2O3-C material has the optimal comprehensive performance when adding 4.5% SiC polymer precursor and 1.5% Zn powder; at low temperatures, Zn powder melts and forms metal bonding phases in the material system; at medium temperatures, the pyrolysis reaction of the SiC polymer precursor and the catalysis of Zn powder after evaporation make the system form SiC fiber bonding phases. They work together to give Al2O3-C unfired slide plate material high medium- and low-temperature strength, which overcomes the failure problem caused by the low strength in application. [ABSTRACT FROM AUTHOR]

Electric spark dressing is an effective dressing method for metal-bonded diamond grinding wheel that offers high precision, high efficiency, and low cost. This study focused on the influence of discharge voltage, discharge current, and power pulse width on the surface morphology of the grinding wheel. The electric spark dressing experiments on metal-bonded grinding wheel and the grinding experiments of SiC ceramics were carried out, using a single-factor method. The surface morphology of the grinding wheel and the surface roughness of the workpiece were analyzed after removing a certain volume of SiC ceramics. It was found that larger electrical parameters could improve the dressing efficiency, and they could also cause adverse effects on the grinding wheel surface such as abrasive shedding, looseness, and bond melting recasting. In the early stage of grinding wheel, surface damage was serious, and grinding workpiece surface roughness was poor. These findings can serve as a practical reference for the selection of electric spark dressing for metal bond diamond grinding wheels. [ABSTRACT FROM AUTHOR]

Metal dioxo chemistry and its diverse reactivity are presented with an emphasis on the mechanisms of reactivity. Work from approximately the last decade is surveyed and organized by metal. In particular, the chemistry of cis-dioxo metal complexes is discussed at length. Reactions are grouped by generic type, including addition across a metal oxo bond, oxygen atom transfer, and radical atom transfer reactions. Attention is given to advances in deoxygenation chemistry, oxidation chemistry, and reductive transformations. [ABSTRACT FROM AUTHOR]

Considerable effort has been invested in the development of non‐centrosymmetric (NCS) inorganic solids for ferroelectricity‐, piezoelectricity‐ and, particularly, optical nonlinearity‐related applications. While great progress has been made, a persistent problem is the difficulty in constructing NCS materials, which probably stems from non‐directionality and unsaturation of the ionic bonds between metal counter‐cations and covalent anionic modules. We report herein a secondary‐bond‐driven approach that circumvents the cancellation of dipole moments between adjacent anionic modules that has plagued second‐harmonic generation (SHG) material design, and which thereby affords a polar structure with strong SHG properties. The resultant first NCS counter‐cation‐free iodate, VO2(H2O)(IO3) (VIO), a new class of iodate, crystallizes in a polar lattice with ∞1[ ${{}_{{\rm { \infty }}}{}^{{\rm { 1}}}{\rm { [}}}$ VO2(H2O)(IO3)] zigzag chains connected by weak hydrogen bonds and intermolecular forces. VIO exhibits very large SHG responses (18 × KH2PO4 @ 1200 nm, 1.5 × KTiOPO4 @ 2100 nm) and sufficient birefringence (0.184 @ 546 nm). Calculations and crystal structure analysis attribute the large SHG responses to consistent polarization orientations of the ∞1[ ${{}_{{\rm { \infty }}}{}^{{\rm { 1}}}{\rm { [}}}$ VO2(H2O)(IO3)] chains controlled by secondary bonds. This study highlights the advantages of manipulating the secondary bonds in inorganic solids to control NCS structure and optical nonlinearity, affording a new perspective in the development of high‐performance NLO materials. [ABSTRACT FROM AUTHOR]

Al laminates are widely used in various applications due to their light weight, corrosion resistance, and good electrical conductivity. In this work, aluminum laminates were reinforced with glass fibers and a boron nitride (BN) epoxy resin. Different concentrations of BN (0, 0.3, 0.6, 0.9, and 1.2 wt.%) were incorporated into the epoxy matrix. The laminates were prepared using a vacuum infusion process (VIP) technique. The addition of BN significantly improved the thermal conductivity of the composites. To further improve the interfacial adhesion between the aluminum alloy sheets and the composite layers, plasma surface treatment was applied to the 6061-T6 aluminum alloy sheets. Plasma surface treatment is a well-known technique that can modify the surface properties of materials, including roughness, wettability, and chemical functionality. By introducing surface roughness and functional groups, plasma treatment can improve adhesion between dissimilar materials. After plasma treatment, the surface morphology and composition of the aluminum alloy sheets were analyzed using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive spectrometry (SEM-EDS). XPS provides information about the chemical composition and bonding state of the surface, while SEM-EDS provides a detailed view of the surface morphology and elemental distribution. Surface roughness and wettability were measured using a surface roughness tester and a contact angle goniometer. The Al/GF/BN/EP laminates were prepared using a thermoforming technique. Mechanical properties including peel, interlaminar shear, tensile, and flexural strength were evaluated. The laminates prepared by plasma surface treatment showed improved mechanical properties with increasing BN concentration up to 0.9 wt.%. This improvement can be attributed to the synergistic mechanism of mechanical and chemical bonding between the metal layer and the composite layer, which is facilitated by the increased surface roughness and the presence of functional groups (C–N and C=N). [ABSTRACT FROM AUTHOR]

Most diseases that affect human beings across the world are now treated with drugs of organic origin. However, some of these are associated with side effects, toxicity, and resistance phenomena. For the treatment of many illnesses, the development of new molecules with pharmacological potential is now an urgent matter. The biological activities of metal complexes have been reported to have antitumor, antimicrobial, anti-inflammatory, anti-infective and antiparasitic effects, amongst others. Metal complexes are effective because they possess unique properties. For example, the complex entity possesses the effective biological activity, then the formation of coordination bonds between the metal ions and ligands is controlled, metal ions provide it with extraordinary mechanisms of action because of characteristics such as d-orbitals, oxidation states, and specific orientations; metal complexes also exhibit good stability and good physicochemical properties such as water solubility. Platinum is a transition metal widely used in the design of drugs with antineoplastic activities; however, platinum is associated with side effects which have made it necessary to search for, and design, novel complexes based on other metals. Copper is a biometal which is found in living systems; it is now used in the design of metal complexes with biological activities that have demonstrated antitumoral, antimicrobial and anti-inflammatory effects, amongst others. In this review, we consider the open horizons of Cu(II)- and Pt(II)-based complexes, new trends in their design, their synthesis, their biological activities and their targets of action. [ABSTRACT FROM AUTHOR]

Oxidative modifications of amino acid side chains in proteins are a hallmark of oxidative stress, and they are usually regarded as structural damage. However, amino acid oxidation may also have a protective effect and may serve regulatory or structural purposes. Here, we have attempted to characterize the global redox role of the 20 proteinogenic amino acids in animals by analyzing their usage frequency in 5 plausible evolutionary paradigms of increased oxidative burden: (i) peroxisomal proteins versus all proteins, (ii) mitochondrial proteins versus all proteins, (iii) mitochondrially encoded respiratory chain proteins versus all mitochondrial proteins, (iv) proteins from long-lived animals versus those from short-lived animals, and (v) proteins from aerobic, free-living animals versus those from facultatively anaerobic animals. We have found that avoidance of cysteine in the oxidative condition was the most pronounced and significant variation in the majority of comparisons. Beyond this preeminent pattern, only local signals were observed, primarily increases in methionine and glutamine as well as decreases in serine and proline. Hence, certain types of cysteine oxidation appear to enforce its proteome-wide evolutionary avoidance despite its essential role in disulfide bond formation and metal ligation. The susceptibility to oxidation of all other amino acids appears to be generally unproblematic, and sometimes advantageous. [ABSTRACT FROM AUTHOR]

The objective of this work is to study the effect of time during the bonding process of alumina with an industrial aluminum 6060 alloy by the technique of solid-state welding at 600°C. Optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, corrosion tests, and microhardness measurements were used as characterization techniques. The extended time during the bonding process had an effect on the microstructure of the interface and its mechanical properties. Oxygen diffusion was detected across the aluminum alloy/alumina interface. A recrystallization reaction developed on the aluminum side during the bonding process, which affected the aluminum alloy hardness values. By bonding metal to ceramic, it allows the use of ceramics in automotive engines to reduce weight, increase thrust-to-weight ratio and operating temperature, and improve working efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Treatment of the rhodium pincer complexes [RhCl(RPm)] (RPm = N,N′-bis(di-R-phosphinomethyl)perimidinylidene, R = Ph, Cy) with triphenylcyclopropenium hexafluorophosphate affords rhodacyclobutadiene complexes. These in turn react with activated alkynes (RC≡CCO2Me, R = H, CO2Me) to afford unusually stable cyclopropenylvinyls, implicating the intermediacy of σ-cyclopropenyl isomers. In contrast, treatment of [RhCl{py(NHPtBu2)2-2,6}] with the same reagent instead results in double functionalisation (SEAr) at the pincer backbone. [ABSTRACT FROM AUTHOR]

The demolding process of electroforming technology in fabricating microstructured optical-functional thin films produces the problem of excessive bonding between the metal substrate and the metal replica, which triggers the deformation of the microstructure and the reduction of precision, and the deposition of Cr–O–C discrete nuclei at the interface can play a good role in assisting the demolding effect. In this paper, the tensile deformation of polycrystalline Cu/Ni and Cu/Cr–O–C/Ni composites is investigated using molecular dynamics methods. The results show that the Cu/Ni model produces a large number of HCP structures during stretching, with holes at the interface and a large number of Cu atoms transferring to the Ni layer. The addition of the Cr–O–C layer reduces the yield strength of the Cu/Cr–O–C/Ni model by 26.41%, and at the same time, the dislocation proliferation at the interface is reduced, and the fracture is at the centralized interface, and the fracture time is reduced by 90.8%. The higher number of Cr–O–C atoms at the interface decreases the transfer of Cu atoms to the Ni layer. The results provide a possible explanation for the Cr–O–C layer-assisted precision electrodeposition debonding. [ABSTRACT FROM AUTHOR]

In this work, the interfacial structure, adhesion properties, and electronic structure of the Al(001)/MgAl2O4(001) interface are investigated via density functional theory calculations. Considering different termination atoms and stacking sites, six interfacial models are explored. The results show that the OAlO-terminated O-top stacking configuration has the greatest interfacial adhesion work of 2.51 J m−2. The nature of bonding between atoms at the Al(001)/MgAl2O4(001) interface is determined by analyzing their interfacial electronic structures, such as valence charge density difference, Bader charge, and density of states. The atoms of the Al(001)/MgAl2O4(001) OAlO-terminal exhibit not only the Al-Al metal bonding but also ionic bonding. For the O-top and two hollow configurations, Al-O covalent bonding components are also present, which mainly originate from the coupling between the Al-3p and O-2p orbitals. In turn, the OAlO-terminated O-top stacking configuration possesses deeper negative energy bands in the Al-O resonance peaks of the interfacial atoms than the OAlO-terminated hollow stacking configuration, resulting in stronger interfacial bonding. Finally, the OAlO-terminated O-top stacking interface corresponds to the most stable interfacial structure. [ABSTRACT FROM AUTHOR]

Eutectogels are gaining attention in flexible device applications for their superior ionic conductivity, stability, biocompatibility, and cost‐effectiveness. However, most existing eutectogels suffer from low strength and toughness. Herein, ultra‐tough and highly stretchable polyacrylamide (PAM) eutectogels featuring a dual‐crosslinked network comprising chemical cross‐linking and physical cross‐linking facilitated by metal coordination bonds and hydrogen bonds are developed. This is achieved through a controlled strategy involving polymerization of acrylamide in a coordinated metal salt‐type deep eutectic solvent (DES) combined with a non‐coordinated choline chloride (ChCl)‐type DES mixture. By varying the molar ratio of these two types of DES, exceptional and adjustable mechanical properties of the resulting eutectogel are achieved, including a high tensile strength ranging from 2.9 to 8.2 MPa and elongation at break ranging from 1725 to 747%, at a 70 wt% DES content. Furthermore, the reversible non‐covalent crosslinking in these eutectogels enables self‐recovery and self‐healing capabilities of eutectogels. The prepared eutectogels also exhibit outstanding ionic conductivity (3.56 mS cm−1), making them well‐suited for use as strain sensors in human motion detection. The toughening strategy is universally effective for creating tough eutectogels using coordinated metal salt‐type DES with various metal ions, as well as a diverse range of coordinatable polymers. [ABSTRACT FROM AUTHOR]

Many bio-applicable materials, medical devices, and prosthetics combine both polymer and metal components to benefit from their complementary properties. This goal is normally achieved by their mechanical bonding or casting only. Here, we report an alternative easy method for the chemical grafting of a polymer on the surfaces of a metal or metal alloys using alkoxy amine salt as a coupling agent. The surface morphology of the created composites was studied by various microscopy methods, and their surface area and porosity were determined by adsorption/desorption nitrogen isotherms. The surface chemical composition was also examined by various spectroscopy techniques and electrokinetic analysis. The distribution of elements on the surface was determined, and the successful bonding of the metal/alloys on one side with the polymer on the other by alkoxy amine was confirmed. The composites show significantly increased hydrophilicity, reliable chemical stability of the bonding, even interaction with solvent for thirty cycles, and up to 95% less bacterial adhesion for the modified samples in comparison with pristine samples, i.e., characteristics that are promising for their application in the biomedical field, such as for implants, prosthetics, etc. All this uses universal, two-step procedures with minimal use of energy and the possibility of production on a mass scale. [ABSTRACT FROM AUTHOR]

The pulley structure has been widely employed to improve mechanical properties. Polyrotaxane‐based waterborne polyurethane (WPU) typically exhibits good tensile strength and Young's modulus. However, achieving outstanding self‐healability of polyrotaxane‐based WPU under mild conditions generally proves insufficient solely relying on host‐guest interactions. Herein, a strategy that constructs a triple synergy of host‐guest interaction, hydrogen bonds, and metal coordination bonds by sequentially introducing tannic acid (TA) and Fe3+ is proposed to prepare polyrotaxane‐based WPU with excellent mechanical performance and high self‐healable capability. Besides the reversible non‐covalent bonding contributing to intrinsic self‐healing, the unique sliding motion of WPU's molecule chain acts as a driving force, promoting efficient contact among reversible bonds. Notably, benefiting from the sliding motion of β‐cyclodextrin (β‐CD) along a chain, the dynamic reconstruction of hydrogen bonds and metal coordination bonds, the resulting supramolecular WPU exhibited a tensile strength of 46.05 MPa and a toughness of 130.30 MPa, with satisfactory self‐healing performance (tensile strength healing efficiency of more than 95%). This work enriches the self‐healing mechanism and expands the concepts for the design of resilient self‐healing environmentally friendly supramolecular WPU. [ABSTRACT FROM AUTHOR]

Diacetylenedisalicylic acid is a new rigid linker molecule, capable of forming strong chelate bonds with metal cations. Its monosubstituted salts with dimethylamine and sodium form 1D and 2D coordination polymers, whose structures were solved from single crystals, along with the dimethyl ester of diacetylenedisalicylic acid. The structure of the dimethyl ester is characterized by a dense co‐facial π‐stacking of molecules with a dominance of van der Waals interactions between the stacks. The angle between the stack direction and the butadiyne groups does not meet the Enkelmann criterion for polymerization in a crystal. In contrast to the dimethyl ester, both salts have a rigid framework with channels filled with disordered solvent molecules. Photoluminescence spectra of the acid and its dimethyl ester have been studied. Thermal analysis of the acid confirms its high thermal stability to 286°C. The acid and its dimethyl ester are prone to polymerization on further heating followed by 50–52% mass loss, forming an amorphous carbon residue at 1000°C. [ABSTRACT FROM AUTHOR]

This overview aims at gathering the various existing works on interphases within epoxy/metal bonded assemblies. Indeed, this particular area plays an important role on the adhesion but also on the behavior in wet environment. Polymeric materials being hydrophilic, water diffusion occurs when they are in a humid environment. The water molecules then have an important impact on the mechanical and physical properties. The effect of water on the interfacial properties of adhesive joints is large discussed in literature. In this article, a complete interphase formation model is be proposed. This two-scenario model explain all the experimental results observed in the literature on the interfaces of a bonded joint. Moreover, hypotheses is made on the water diffusion mechanisms and the diffusive properties of the interface. This is allow explaining the change of the fracture surface observed during the wet aging of a bonded joint. A large number of studies have observed the transition from cohesive to adhesive failure. [ABSTRACT FROM AUTHOR]

Separation and reuse of the catalytically active metal complexes are persistent issues in homogeneous catalysis. Supported Ionic Liquid Phase (SILP) catalysts, where the catalytic center is dissolved in a thin film of a stable ionic liquid, deposited on a solid support, present a promising alternative. However, the dissolution of the metal center in the film leaves little control over its position and its activity. We present here four novel, task‐specific ionic liquids [FPhnImHR]I (n=1, 2; R=PEG2, C12H25), designed to self‐assemble on a silica surface without any covalent bonding and offering a metal binding site in a controlled distance to the support. Advanced multinuclear solid‐state NMR spectroscopic techniques under Magic Angle Spinning, complemented by molecular dynamics (MD) simulations, allow us to determine their molecular conformation when deposited inside SBA‐15 as a model silica support. We provide here conceptual proof for a rational design of ionic liquids self‐assembling into thin films, opening an avenue for a second, improved generation of SILP catalysts. [ABSTRACT FROM AUTHOR]

Collective interactions are a novel type of bond between metals and AX3 fragments with an electropositive central atom, A, and electronegative X substituents. Here, using electrostatic potential maps and state-of-the-art bonding analysis tools we have shown that collective interactions are anti-electrostatic cation⋯π-Hole or cation⋯lp-Hole interactions. [ABSTRACT FROM AUTHOR]

This study aimed to explore the reinforcement effect of halloysite nanotubes (HNTs) in self‐healing natural rubber based on metal thiolate ion networks. The amount of HNTs was varied at five levels (2, 4, 6, 8, and 10 phr) in order to assess the optimum amount of filler for self‐healing efficiency and mechanical recovery performance. Fourier‐transform infrared (FTIR) provides evidence for the reversible ionic bonding, facilitated by Zn2+ and S− bonding from the metal thiolate vulcanization with rubber molecular chains. Scanning electron microscopy (SEM) revealed that the NR/HNTs composites with lower filler loading exhibited better recovery, as there were no observable gaps between the cut surfaces of the samples. The results also revealed that addition of HNTs resulted in a significant improvement in the mechanical performance, particularly the tensile strength, which increased by approximately 20%–75%. Furthermore, the extent of healing after the broken pieces were brought in contact with each other varied from 87% to 98%, depending on HNT concentration. Highlights: Fabrication of self‐healing elastomers based on natural rubber.Self‐healing NR presented enhanced mechanical performance with addition of HNTs.HNTs lumen endows the composites with excellent self‐healing efficiency.Developed NR/HNTs composite exhibited room temperature self‐healing properties.Reversible ionic bonding expedited by Zn2+ contributes in excellent self‐healing. [ABSTRACT FROM AUTHOR]

The study of alkaline earth metal complexes is undergoing a renaissance. Stable molecular species featuring Mg–Mg bonds were reported in 2007 and their reactivity has since been intensively investigated. Motivated by this work, efforts have also been devoted to the synthesis of complexes featuring Be–Be and Ca–Ca bonds. These collective endeavours have revealed that the chemistry of the group 2 metals is richer and more complex than had previously been appreciated. Here, a discussion of the nature of homometallic alkaline earth bonding is presented, recent synthetic advances are described, and future directions are considered. [ABSTRACT FROM AUTHOR]

A series of unsymmetric tetradentate β-diketiminato rare-earth metal monoalkyl complexes were synthesized, and their catalytic behavior has been well developed. Indole-incorporated β-diketiminato proligands H2L (L = MeC(NDipp)CHC(Me)NCH2CH2-3-(1-R-C8H4N), R = CH2-(2-C4H7O), L1; R = (CH2)2OMe, L2; Dipp = 2,6-iPr2C6H3) were prepared by the reaction of an arylamino-enone with 1-substituted-tryptamine in good yields. Treatment of the proligands with the rare-earth metal trialkyl complexes RE(CH2SiMe3)3(THF)2 generated the corresponding unsymmetric N,N,C,O-tetradentate β-diketiminato rare-earth metal monoalkyl complexes LRE(CH2SiMe3) (L1, RE = Y (1a), Gd (1b), Yb (1c), Lu (1d); L2, RE = Y (2a), Gd (2b), Yb (2c), and Lu(2d)). During the process, the activation of the sp2 C–H bond at the 2-position of the indole ring led to the formation of an unprecedented β-diketiminato dianion L2−, bonding to the rare-earth metal ions in a chelating N,N,C,O-tetradentate manner. Further studies indicated that these tetradentate rare-earth metal complexes could initiate the Oppenauer oxidation of secondary alcohols into the corresponding ketones in high yields. In the case of primary alcohols, a tandem Oppenauer oxidation and cross-aldol condensation occurred unexpectedly. Various α-mono-substituted benzylidene acetones, α,α′-bis-substituted benzylidene acetones and cyclohexanones were obtained under mild conditions only by controlling the molar ratio of alcohols to ketones. Notably, all these alkenylation ketones exhibited exclusive E configuration. [ABSTRACT FROM AUTHOR]

Quantum chemical calculations have b‐een carried out on the inverse sandwich type complexes formed between coinage and alkali metals with Be3 and Zn3 rings. Calculations reveal that the complexes are stable toward dissociation. Their Lewis acidic character has been evaluated using fluoride ion affinity (FIA) calculation, which reveals their strong acidic character. Topological analysis of electron density has also been performed to investigate the nature of the bond between the metal and the fluoride ion. Calculations reveal non covalent nature in case of alkali series and covalent nature in case of coinage metal series. [ABSTRACT FROM AUTHOR]

Using density functional theory, polyols were used as model ligands for Cu+/Cu2+ complexes to study the role of the hydrogen bond network on the metal binding affinity. In addition to the gas phase studies, the calculations were performed in 1‐decanol and DMSO solvents. The Cu2+ complexes were the most stable complexes with the highest bond dissociation energies (BDE). The presence of three H‐bonds in the first shell increased BDE values up to 17.99 and 57.07 kcal/mol for Cu+ and Cu2+ complexes in the gas phase, respectively, whereas the presence of another three H‐bonds in the second shell increased BDE values up to 7.27 and 24.35 kcal/mol for Cu+ and Cu2+ complexes in the gas phase, respectively. Therefore, this H‐bond network caused, for example, a more stable Cu+ complex with a formation constant of 1.4 × 1017 times. The natural bond orbital (NBO), atoms in molecules (AIM), and reduced density gradient (RDG) analyses showed that the intramolecular hydrogen bond network led to the enhancement of metal‐binding affinity. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) are multi-dimensional network of crystalline material held together by bonding of metal atoms and organic ligands. Owing to unique structural, chemical, and physical properties, MOFs has been used for enzyme immobilization to be employed in different catalytic process, including catalytic degradation of antibiotics. Immobilization process other than providing large surface provides enzyme with enhanced stability, catalytic activity, reusability, and selectivity. There are various approaches of enzyme immobilization over MOFs including physical adsorption, chemical bonding, diffusion and in situ encapsulation. In situ encapsulation is one the best approach that provides extra stability from unfolding and denaturation in harsh industrial conditions. Presence of antibiotic in environment is highly damaging for human in particular and ecosystem in general. Different methods such as ozonation, oxidation, chlorination and catalysis are available for degradation or removal of antibiotics from environment, however these are associated with several issues. Contrary to these, enzyme immobilized MOFs are novel system to be used in catalytic degradation of antibiotics. Enzyme@MOFs are more stable, reusable and more efficient owing to additional support of MOFs to natural enzymes in well-established process of photocatalysis for degradation of antibiotics aimed at environmental remediation. Prime focus of this review is to present catalytic degradation of antibiotics by enzyme@MOFs while outlining their synthetics approaches, characterization, and mechanism of degradation. Furthermore, this review highlights the significance of enzyme@MOFs system for antibiotics degradation in particular and environmental remediation in general. Current challenges and future perspective of research in this field are also outlined along with concluding comments. [ABSTRACT FROM AUTHOR]

A new quinoline–thiosemicarbazone derivative, 5,7-dichloro-8-hydroxyquinoline-2-carboxaldehyde-4-phenyl-3-thiosemicarbazone (QPS) and seven complexes of QPS with d-transition metals (Mn, Fe, Co, Ni, Cu, Zn, Cd) were successfully synthesized. Spectrometry methods such as IR, ESI-MS, and 1H NMR were utilized to determine the structure of complexes that almost all complexes form the metal:ligand ratio of 1:1, except for FeQPS, which forms a 1:2 ratio. The center metals bond to QPS through O, Nquinoline and Nthiosemicarbazone. Four tested complexes (MnQPS, CoQPS, NiQPS, CuQPS) show medium inhibition to KB and Hep-G2 cancer cell lines. ZnQPS has the high activity against KB and Hep-G2 (IC50 = 13.51 and 10.28 μg/mL) and a high impact against the LU cancer cell line (IC50 = 2.0 μg/mL). CdQPS complexes showed excellent activity on both KB and Hep-G2 with IC50 very low, IC50 = 3.12 and 3.06 μg/mL, which is much lower than cisplatin. [ABSTRACT FROM AUTHOR]

The direct bonding of A5052 aluminum (Al) alloy to the engineering polymer poly(ether ether ketone) (PEEK) using an atmospheric pressure plasma-assisted process was demonstrated. The effect of plasma irradiation on the bonding surface of metal resin on the bonding strength following thermal press fitting method was investigated. Specimens bonded by plasma irradiation on the PEEK surface only showed a high tensile shear stress of 15.5 MPa. With increasing plasma irradiation time, the bond strength of the samples bonded to the PEEK surface by plasma irradiation increased. The increase in the bond strength between metals and polymers following direct bonding is caused by the addition of oxygen functional groups on the polymer. In contrast, specimens in which only the Al was exposed to the plasma showed a decrease in bond strength compared with unirradiated samples. This reduction in bond strength is attributed to the forming magnesium oxide, which forms in the early stages of participation due to plasma irradiation. [ABSTRACT FROM AUTHOR]