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The quantum nuclear kinematic interactions with electrons (or nonadiabatic interactions) are the inherent driving force that possibly causes a mixture of the adiabatic electronic states in molecules. Particularly in systems whose electron wavepackets lie in a densely quasi-degenerate electronic-state manifold where many-dimensional and many-state nonadiabatic interactions last continually, we have found before that those extensive mixings can lead to a quantum electronic-state chaos [K. Takatsuka and Y. Arasaki, J. Chem. Phys. 159, 074110 (2023)]. This chaos of electron dynamics is a new kind yet generic. This Communication identifies the mathematical/physical mechanism of this class of chaos by means of the collective coordinate analysis of the nonadiabatic interactions, along with the numerical applications to excited states of boron clusters. Some physical consequences of the present chaos are also discussed. [ABSTRACT FROM AUTHOR]

Synthetic antiferromagnetic (SAF) nanoplatelets (NPs) with perpendicular magnetic anisotropy based on archetype SAF structures, e.g., Pt/Co/Ru/Co/Pt are of particular interest for torque-related bio-applications due to their large uniaxial magnetic anisotropy. However, when the diameter of the NPs is reduced, the magnetic properties change. For instance, the coercive field increases and starts to vary strongly from NP to NP in a batch due to an increased variation in the reversal probability dominated by local defects. In this study, we investigate how the concentration of boron (B) in Co 1 − x B x affects the switching properties of NPs, because the addition of B renders the Co layer amorphous and hence introduces more defects. Moreover, it reduces variations in local crystalline anisotropy making the magnetic properties of the NPs more soft. Specifically, we show that the coercivity of the NPs decreases with higher B concentration. This decrease is explained by two mechanisms: (i) the loss of interfacial anisotropy due to less Co–Pt hybridization at the Pt–Co interface and (ii) an increase in the surface's magnetic domain nucleation site density leading to a narrower distribution of the coercivity of an ensemble of NPs. This understanding will greatly help the field of NP-torque related applications as the spread in applied torque from the NPs to their surroundings can be homogenized. [ABSTRACT FROM AUTHOR]

Excess minority carriers create boron-related recombination centers that degrade the efficiency of the non-particle-irradiated silicon solar cells. However, the carrier-induced reactions among the radiation-induced defects are poorly understood for devices exposed to particle radiation. This study investigates the structure, electronic properties, formation and annihilation mechanisms, and diffusion dynamics of the carrier-induced defects in particle-irradiated boron-doped silicon using density-functional modeling and junction spectroscopy. By revisiting the ground-state structures of the boron-di-interstitial clusters (B I 2), we find that the calculated acceptor and donor levels of such defects agree well quantitatively with the carrier-induced deep-level transient spectroscopy (DLTS) hole emission signatures at 0.43 and 0.53 eV above the valence band edge (E v), respectively. We also find that the formation of B I 2 is thermally activated by an energy of 0.50 eV, which we explain theoretically by the reduction of the migration barrier of mono-interstitials to 0.53 eV in the presence of excess minority carriers. Moreover, we discover that the B I 2 are potentially mobile with a migration barrier of 1.18 eV, contrary to the present understanding. [ABSTRACT FROM AUTHOR]

Boron-based compounds have triggered substantial attention due to their multifunctional properties, incorporating excellent hardness and superconductivity. While tetragonal metal borides LiB4 and NaB4 with BaAl4-type structure and striking clathrate boron motif have been induced under compression, there is still a lack of deep understanding of their potential properties at ambient pressure. We herein conduct a comprehensive study on I4/mmm-structured LiB4 and NaB4 under ambient pressure via first-principles calculations. Remarkably, both LiB4 and NaB4 are found to possess high Vickers hardness of 39 GPa, which is ascribed to the robust boron framework with strong covalency. Furthermore, their high hardness values together with distinguished stability make them highly potential superhard materials. Meanwhile, electron–phonon coupling analysis reveals that both LiB4 and NaB4 are conventional phonon-mediated superconductors, with critical temperatures of 6 and 8 K at 1 atmosphere pressure (atm), respectively, mainly arising from the coupling of B 2p electronic states and the low-frequency phonon modes associated with Li-, Na-, and B-derived vibrations. This work provides valuable insights into the mechanical and superconducting behaviors of metal borides and will boost further studies of emergent borides with multiple functionalities. [ABSTRACT FROM AUTHOR]

Boron-based compounds have triggered substantial attention due to their multifunctional properties, incorporating excellent hardness and superconductivity. While tetragonal metal borides LiB4 and NaB4 with BaAl4-type structure and striking clathrate boron motif have been induced under compression, there is still a lack of deep understanding of their potential properties at ambient pressure. We herein conduct a comprehensive study on I4/mmm-structured LiB4 and NaB4 under ambient pressure via first-principles calculations. Remarkably, both LiB4 and NaB4 are found to possess high Vickers hardness of 39 GPa, which is ascribed to the robust boron framework with strong covalency. Furthermore, their high hardness values together with distinguished stability make them highly potential superhard materials. Meanwhile, electron–phonon coupling analysis reveals that both LiB4 and NaB4 are conventional phonon-mediated superconductors, with critical temperatures of 6 and 8 K at 1 atmosphere pressure (atm), respectively, mainly arising from the coupling of B 2p electronic states and the low-frequency phonon modes associated with Li-, Na-, and B-derived vibrations. This work provides valuable insights into the mechanical and superconducting behaviors of metal borides and will boost further studies of emergent borides with multiple functionalities. [ABSTRACT FROM AUTHOR]

In this work, Er5Si3B0.5 compound with the Mn5Si3-type hexagonal structure was synthesized, and the structure, magnetic properties, and the magnetocaloric effect were investigated theoretically and experimentally. The magnetic measurement results show a complex successive magnetic transition below T N. However, the magnetization of the Er5Si3B0.5 compound below T N is saturated under lower magnetic field relative to the Er5Si3 compound. Theoretical calculation indicates that this was attributed to the enhanced inter-orbital exchange interaction after doping B element. The complicated successive magnetic transitions contribute to the table-like magnetocaloric effect observed in the Er5Si3B0.5 compound with a wide temperature region. The maximum magnetic entropy change and the temperature averaged entropy change (30) are 10.1 and 9.02 J/kg K for the Er5Si3B0.5 compound under varying magnetic fields from 0 to 5 T, respectively. The temperature averaged entropy change (30) is reduced by just 11% compared to the maximum magnetic entropy change. While presenting an ideal magnetic refrigeration material with a large table-like magnetocaloric effect for hydrogen liquefaction, our work also demonstrates the feasibility of regulating magnetic behavior through enhanced orbital exchange interactions to develop magnetic refrigeration materials with outstanding performance. [ABSTRACT FROM AUTHOR]

Boron phosphide (BP) is a (super)hard semiconductor constituted of light elements, which is promising for high demand applications at extreme conditions. The behavior of BP at high temperatures and pressures is of special interest but is also poorly understood because both experimental and conventional ab initio methods are restricted to studying refractory covalent materials. The use of machine learning interatomic potentials is a revolutionary trend that gives a unique opportunity for high-temperature study of materials with ab initio accuracy. We develop a deep machine learning potential (DP) for accurate atomistic simulations of the solid and liquid phases of BP as well as their transformations near the melting line. Our DP provides quantitative agreement with experimental and ab initio molecular dynamics data for structural and dynamic properties. DP-based simulations reveal that at ambient pressure, a tetrahedrally bonded cubic BP crystal melts into an open structure consisting of two interpenetrating sub-networks of boron and phosphorous with different structures. Structure transformations of BP melt under compressing are reflected by the evolution of low-pressure tetrahedral coordination to high-pressure octahedral coordination. The main contributions to structural changes at low pressures are made by the evolution of medium-range order in the B-subnetwork and, at high pressures, by the change of short-range order in the P-subnetwork. Such transformations exhibit an anomalous behavior of structural characteristics in the range of 12–15 GPa. DP-based simulations reveal that the Tm(P) curve develops a maximum at P ≈ 13 GPa, whereas experimental studies provide two separate branches of the melting curve, which demonstrate the opposite behavior. Analysis of the results obtained raises open issues in developing machine learning potentials for covalent materials and stimulates further experimental and theoretical studies of melting behavior in BP. [ABSTRACT FROM AUTHOR]

Recent work on atomic-precision dopant incorporation technologies has led to the creation of both boron and aluminum δ -doped layers in silicon with densities above the solid solubility limit. We use density functional theory to predict the band structure and effective mass values of such δ layers, first modeling them as ordered supercells. Structural relaxation is found to have a significant impact on the impurity band energies and effective masses of the boron layers, but not the aluminum layers. However, disorder in the δ layers is found to lead to a significant flattening of the bands in both cases. We calculate the local density of states and doping potential for these δ -doped layers, demonstrating that their influence is highly localized with spatial extents at most 4 nm. We conclude that acceptor δ -doped layers exhibit different electronic structure features dependent on both the dopant atom and spatial ordering. This suggests prospects for controlling the electronic properties of these layers if the local details of the incorporation chemistry can be fine-tuned. [ABSTRACT FROM AUTHOR]

Diamond films possess numerous extraordinary physical and chemical properties, but their high-temperature applications are limited by its poor thermal stability. Herein, we fabricated the undoped microcrystalline diamond (MCD) film and heavy boron-doped diamond (h-BDD-1, 2.94 × 1021 atoms·cm−3; h-BDD-2, 9.10 × 1021 atoms·cm−3) films to investigate the effect of boron doping on the thermal stability of diamond films. A series of evidences, including air annealing experiments, thermogravimetric-differential scanning calorimetry (TG-DSC) analysis, and in-situ ultra-high-temperature confocal laser-scanning microscope (CLSM), demonstrated that the thermal stability of diamond films was obviously enhanced by boron doping. Consequently, the h-BDD-2 film exhibited the best thermal stability with an initial oxidation temperature above 900 °C, which was much higher than that of MCD film (709 °C). By deconvolving the X-ray photoelectron spectra, we believed that the transition of B–C bonds to stable oxy-boron carbide complexes (B 4 O–C, B 3 O–C) is the key to improving the thermal stability. These results not only reveal a new antioxidant mechanism of boron-doped diamond films but also pave a way for the application of diamond in high-temperature environments. [ABSTRACT FROM AUTHOR]

Boron- B is an essential element for the growth and development of plants. Its deficiency in hot, dry areas with calcareous soils can significantly reduce agricultural crop production. To study the impact of B fertilization, an experiment was conducted using a completely randomized design with seven treatments, including control, foliar spray (0.5, 1, and 2 g L−1 boric acid), and fertigation (0.5, 1, and 2 g L−1 boric acid). The experiment, with three replicates, was carried out in greenhouse conditions on pepper plants (Capsicum annuum cv. Lorca). The highest fruit yield was achieved with foliar spray at a concentration of 0.5 g L−1 and fertigation at 1 g L−1. Overall, the use of B fertilizer increased the concentration of macronutrients such as potassium-K (up to 27.79%), phosphorus-P (up to 59%), calcium-Ca (up to 49.61%), and magnesium-Mg (up to 158%), as well as micronutrients like iron-Fe (up to 59.55%), manganese-Mn (up to 29.03%), zinc-Zn (up to 81.81%), copper-Cu (up to 49.33%), B (up to 180%), and sodium-Na (up to 85.19%). It also decreased the concentration of nitrogen-N (up to 15%), sulfur-S (up to 21.36%), and chlorine-Cl (up to 48.02%) in the leaf tissue of pepper plants compared to the control treatment. These changes were influenced by the B concentration and type of fertilization. The results indicate that in calcareous soils with high pH, both fertigation and foliar spray methods can effectively address B deficiency in pepper plants by enhancing element absorption and increasing yield. [ABSTRACT FROM AUTHOR]

Boron doped MoSi 2 particles have been envisioned as sacrificial particles for self-healing thermal barrier coatings (TBCs) but their oxidation behaviour is yet not well understood. In this work, oxidation of MoSi 2 based particle is studied in the temperature range of 1050–1200 °C. The oxidation proceeds from a transient to a steady-state oxidation stage. The kinetics during steady-state oxidation is captured with a thermal diffusion-based model. As compared to the oxidation of pure MoSi 2 particles, the addition of boron strongly enhances the silica formation. Also, a finer dispersion of MoB x in the MoSi 2 matrix accelerates the formation of silica. The oxide growth rate constant increases proportional with the boron content of the MoSi 2 particles. This enhanced oxidation is related to the microstructure of the oxide scale. Upon oxidation, boron yields B 2 O 3 , which promptly merge with SiO 2 to form amorphous borosilicate, hindering the formation of crystalline SiO 2. Consequently, the migration of oxygen in the borosilicate oxide scale is faster than in the silica oxide scale on pure MoSi 2 particles. [ABSTRACT FROM AUTHOR]

Commercially available bioactive glasses (BAGs) are exclusively used in powder form, due to their tendency to crystallize. Silicate BAG 1393 was developed to allow fiber drawing and scaffold sintering, but its slow degradation limits its potential. To enable scaffold manufacturing while maintaining glass dissolution rate close to that of commercially available BAGs, the borosilicate glass 1393B20 was developed. This study investigates the potential of 1393B20 scaffolds to support bone regeneration and mineralization in vitro and in vivo , in comparison to silicate 1393. Both scaffolds supported human adipose stem cells proliferation, either in direct contact for the 1393, or mainly around for the 1393B20. Similarly, both BAGs induced osteogenesis and angiogenesis in vitro , with a better pro-angiogenic influence of the 1393B20. In addition, these scaffolds supported bone regeneration and osteoclast/osteoblast activity in vivo in critical-sized rat calvarial defect. Nevertheless, mineralization and collagen formation were significantly enhanced for the 1393B20, at 3-months post-implantation, assigned to faster and more complete dissolution of the scaffolds. Thus, 1393B20 demonstrates greater promise for bone tissue engineering certainly due to its time-controlled release of boron and silicon. Bioactive glasses (BAGs) show great promise in bone tissue engineering as they effectively bond with bone tissue, fostering integration and regeneration. Silicate BAG 1393 was developed to allow fiber drawing and scaffold sintering, but its slow degradation limits its potential. To enable scaffold manufacturing while maintaining glass dissolution rate close to that of commercially available BAGs, the borosilicate glass 1393B20 was developed. Both BAGs induced osteogenesis and angiogenesis in vitro , with a better pro-angiogenic influence of the 1393B20. The presence of boron in the 1393B20 enhanced mineralization and collagen formation in vivo compared to 1393, probably due to its faster dissolution rate. Here, 1393B20 demonstrated greater promise for bone tissue engineering compared to the well-known 1393 BAG. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of boron difluoro bis(diiminate) complexes have been prepared and used to obtain triflate substituted fluoroborane complexes. The corresponding well-defined bis(borenium) cations were subsequently synthesized and structurally authenticated. We are also presenting the first experimental and theoretical study of bis(borenium) cations that are derivative of cationic borinic acid. [ABSTRACT FROM AUTHOR]

Alternating‐rich copolymer of vinylboronic acid pinacol ester (VBpin) and maleic anhydride (MAH) was found to catalyze direct dehydrative esterification of carboxylic acid and alcohol. The key to the catalytic function is the activation of the MAH unit by the neighboring Lewis acidic boron directly connected to the backbone through the formation of five‐membered ring. The effects of the side‐chain cooperation were clarified through comparisons with the polymers having similar structures and a conventional titanium catalyst as well as the analyses of reactions with carboxylic acid or alcohol. The catalytic activity was enhanced as the molecular weight was higher, which is owing to the structural feature that boron is directly attached to the backbone. The cooperative catalysis is of interest because of its conceptual similarity with enzyme. [ABSTRACT FROM AUTHOR]

The formation of molecular-based functional materials is a key step towards the development of technologies at the nanoscale. Recently, it has been shown that after oxidation of closo-[B10H10]2− anions, an induced aggregation of two cluster units is achieved, retaining their parent B10 backbones as persistent building blocks. Such characterization provides an interesting scenario to further understand relevant factors leading to aggregation in a minimal structure involving two units. Here, we explore the interaction between closo-[B10H10]2− units in two isomers, namely, iso- and trans-[B20H18]2−, involving different intercluster contacts based on B–B and B–H interactions, respectively. Our results show that the inherent spherical aromatic characteristics of the parent closo-[B10H10]2− cluster are persistent in both iso- and trans-[B20H18]2− isomers as an interplay between the spherical aromatic properties from both B10 motifs, leading to an overlap of the shielding regions from shielding cone properties, ascribed as a dual spherical–spherical aromatic cluster. From 11B-NMR features, it came out that trans-[B20H18]2− involves larger differences in comparison to closo-[B10H10]2−, owing to the variation of the B10–B10 backbone provided by the intercluster B-interaction, thus resulting in a more effective aggregation connecting such building units, towards boron-based cluster materials. [ABSTRACT FROM AUTHOR]

A series of barium-boroaluminosilicate [30SiO 2 -11Al 2 O 3 -44B 2 O 3 -5BaO-(10-x)K 2 O-xDy 2 O 3 (with x = 0.25, 0.5, 0.75, 1.0, 1.25, 1.5 mol%)] glasses doped with Dy3+ ions were prepared by the high temperature (melt quenching) method. In the glass matrix, the relationship among structure, luminescence properties, and B/Al ratio was analyzed; also studied are the physical properties of glass and influence of Dy3+ concentration on the luminescence properties. Differential Scanning Calorimeter (DSC) results have shown the glass matrix exhibiting good thermal stability and high resistance to crystallization. FTIR and Raman spectra have confirmed the presence of stretching and bending vibrations of [BO 3 ], [AlO 4 ] and [SiO 4 ] structural units in the prepared glass. The observed UV–Vis–NIR spectra have indicated that the existence of thirteen bands corresponding to the transition Dy3+ ions from 6H 15/2 level to different excited levels; the transmittance curves obtained have shown the transmittance up to 91 %. Increase in Dy3+ concentration is found to decrease the optical band gap; the calculated Judd-Oflet parameter is found to follow the trend Ω 2 ＞Ω 4 ＞Ω 6. Photoluminescence studies have shown three emission peaks which could be associated to the transitions: 4F 9/2 → 6H 15/2 (blue light), 4F 9/2 → 6H 13/2 (yellow light), and 4F 9/2 → 6H 11/2 (red light); the maximum intensity obtained for the glass with x = 0.75 mol%, with spacing between Dy3+ ions being 1.9137 Å; and the decay curve could be fitted with double exponential function. The CIE results have revealed that the chromaticity coordinates are closer to that of standard white light, and the color temperature located in the region of cold white light. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate systematic studies on the influence of Fe 2 O 3 on the structural and optical properties of transparent B 2 O 3 –TeO 2 –Na 2 O glasses containing the different concentrations of Fe 2 O 3. The glasses were prepared via the standard melt quenching method, and the prepared glasses were characterized using, XRD, electron paramagnetic resonance (EPR), FTIR, and UV–visible spectroscopic techniques. Furthermore, we evaluated several physical properties of the glasses, including densities, molar volume, boron-boron separation, and oxygen packing density, with respect to the concentration of Fe 2 O 3 in the host glass matrix. It is observed that the density of the glasses and the average boron-boron distance found increase with Fe 2 O 3 concentration due to the modification in the glass network induced by the dopant ions. EPR spectra reveals the presence resonance signals at g ∼2.04 and g ∼4.26, hence it proves the existence of Fe3+ in distorted octahedral coordination and supported by UV–Vis absorption bands. The FTIR spectra revealed an increase in spectral intensity with the concentration of Fe 2 O 3. This was attributed to the formation of non-bridging oxygens through converting BO 4 units into BO 3 units, which Fe 2 O 3 mediated. The UV–visible spectral analysis showed a decreased energy band gap from 2.26 to 1.51 eV with increased Fe 2 O 3 concentration. Additionally, we determined the Urbach energy, refractive index, optical basicity, and electronegativity, which are presented in detail. [ABSTRACT FROM AUTHOR]

Supramolecular complexes of carbon nanohoops with fullerenes play a key role for the design of novel nanomaterials with technological applications. Herein we investigate with density functional theory (DFT) methods the capability of neutral and dioxidized cycloparaphenylenes (CPPs) to encapsulate all‐boron fullerene B40. Our results show that [9]CPP and [10]CPP are feasible host candidates to encapsulate B40 displaying comparable complexation energies with the all‐carbon analog [10]CPP⊃C60. Upon dioxidation the host‐guest interactions are not affected, whereas the positive charge is delocalized on the CPPs leading to global aromatic character of the hosts. Consequently, the dicationic complexes [n]CPP2+⊃B40 and [10]CPP2+⊃C60 display augmented global shielding cones that strongly shield the guests, as manifested by large upfield shifts in 11B‐NMR and 13C‐NMR signals. Hence, CPP complexes with carbon fullerenes can be extended borospherene B40 host‐guest complexes, as well as to doubly oxidized species stabilized by global host aromaticity, expanding our understanding of carbon nanohoop complexes to boron‐based fullerenes. [ABSTRACT FROM AUTHOR]

The Petasis reaction is a multicomponent reaction of aldehydes, amines and organoboron reagents and is a useful method for the construction of substituted amines. Despite the significant advancement of the Petasis reaction since its invention in 1993, strategies for asymmetric and non‐directed Petasis reactions remain limited. To date, there are very few catalytic asymmetric Petasis reactions and almost all asymmetric reports employ a chiral auxiliary. Likewise, the aldehyde component often requires a directing group, ultimately limiting the reaction's scope. In this Concept, key methods for asymmetric and non‐directed Petasis reactions are discussed, focusing on how these conceptual advances can be applied to solve long‐standing gaps in the Petasis literature. [ABSTRACT FROM AUTHOR]

Summary: Boron (B) is crucial for plant growth and development. B deficiency can impair numerous physiological and metabolic processes, particularly in root development and pollen germination, seriously impeding crop growth and yield. However, the molecular mechanism underlying boron signal perception and signal transduction is rather limited.In this study, we discovered that CPK10, a calcium‐dependent protein kinase in the CPK family, has the strongest interaction with the boron transporter BOR1. Mutations in CPK10 led to growth and root development defects under B‐deficiency conditions, while constitutively active CPK10 enhanced plant tolerance to B deficiency.Furthermore, we found that CPK10 interacted with and phosphorylated BOR1 at the Ser689 residue. Through various biochemical analyses and complementation of B transport in yeast and plants, we revealed that Ser689 of BOR1 is important for its transport activity.In summary, these findings highlight the significance of the CPK10‐BOR1 signaling pathway in maintaining B homeostasis in plants and provide targets for the genetic improvement of crop tolerance to B‐deficiency stress. See also the Commentary on this article by Huang, 243: 1633–1635. [ABSTRACT FROM AUTHOR]

Solidification structure and segregation behavior of S31254 superaustenitic stainless steel ingot containing 0 wt% B and 0.005 wt% B are investigated. The results show that serious element segregation and massive eutectics are present in the center of the ingot. By contrast, the addition of boron reduces the secondary dendrite spacing, the degree of elemental segregation, and the σ phase. Further, the effect of boron on the solidification process is studied by using the high‐temperature confocal laser scanning microscope and combined with Thermo‐Calc thermodynamic simulation results. The results show that boron can widen the solidification temperature range and greatly retard the matrix solidification. The role of boron in refining dendrite structure and inhibiting precipitation is further confirmed. The effect of boron on the constitutive equation of S31254 superaustenitic stainless steel has also been researched through isothermal compression testing in the temperature range of 950–1200 °C and strain rate range of 0.01–10 s−1. The activation energy of the boron‐free and boron‐containing S31254 superaustenitic stainless steels based on the constitutive equation are 427.77 and 495.80 kJ mol−1, respectively. Processing maps indicate that the instability domain is significantly reduced and the hot ductility is improved after the addition of B. [ABSTRACT FROM AUTHOR]

With the incorporation of heteroatomic B into single-atom Fe catalyst (Fe SA -NC), a catalyst named Fe SA -BNC with a configuration of Fe-N 3 B 1 had been synthesized for the oxygen reduction reaction (ORR). The low electronegativity of B induced charge redistribution around the active center Fe, thereby modulating the ORR activity. The Fe SA -BNC catalyst demonstrated an outstanding ORR performance in alkaline conditions, with a half-wave potential of 0.87 V. [Display omitted] • Coordination of low electronegativity B with Fe atom. • Regulating the charge states of the active site Fe. • The decrease of the d -band center of Fe promoting the desorption of ORR intermediates and enhancing the ORR performance. Despite extensive research has been conducted on atomic dispersion catalysts for various reactions, altering the electronic structure of the central metal to enhance electrochemical reactivity remains a challenging task. Herein, the electrochemical reactivity was considerably enhanced by introducing heteroatomic B to adjust the d -band of single Fe center. In specific, the obtained Fe SA -BNC catalyst demonstrated an outstanding ORR performance (E 1/2 = 0.87 V) and exhibited greater long-term durability in alkaline media compared to Pt/C. The performance of Fe SA -BNC in Zn–air battery was also higher than that of Pt/C. According to theoretical calculations, a downward shift in the d -band center of Fe was induced by introducing B, thereby improving the desorption of intermediates and facilitating the oxygen reduction reaction (ORR). [ABSTRACT FROM AUTHOR]

This work investigated the valorization of olive tree pruning debris as a biosorbent for the removal of environmentally hazardous boron from aqueous solution using batch adsorption. For this purpose, a novel, waste-based, boron selective biosorbent from olive tree pruning waste (N-OPW) was synthesized. Alkali pretreatment, followed by glycidyl-methacrylate (GMA) grafting and providing boron selectivity with n-methyl-d-glucamine (NMDG) steps, was applied to the biomass, respectively. N-OPW was characterized using SEM, TGA, and FT-IR analyses. N-OPW showed excellent boron biosorption capacity (21.80 mg/g) in an operation pH range between 2 and 12. The equilibrium was attained in 2 h and the Freundlich isotherm (R2 = 0.997) and pseudo-second-order kinetics (R2 = 0.99) provided the strongest match to experimental data. According to thermodynamic studies, boron adsorption was exothermic (ΔH = −34.14 kJ/mol). The reusability tests with real geothermal water showed that adsorbent had no significant decrease in boron removal capacity while desorbing >99% of the boron adsorbed for three cycles of adsorption/desorption. Results indicated that a promising, reusable, and boron selective biosorbent was successfully synthesized while utilizing olive pruning waste. [ABSTRACT FROM AUTHOR]

The inferior creep ductility of Inconel 718 (IN718) fabricated by selective laser melting (SLM), which is unable to meet aerospace material specification (≥4%), limits its engineering application. Despite persistent optimization efforts in the SLM process and post-heat treatment, this issue remains unresolved. This study involved SLM fabrication of the modified IN718 with trace amounts of LaB6 and/or P, followed by homogenization and double aging heat treatment. The addition of trace LaB6 notably influenced the recrystallized grain structure and carbide precipitation at grain boundaries, while trace P addition had minimal impact. All samples exhibited similar γ′ and γ″ strengthening precipitates. Creep tests conducted at 650°C/690 MPa revealed that the individual modification of LaB6 showed limited improvement in creep performance and P showed no improvement, but the combined addition of LaB6 and P led to a substantial enhancement in creep performance, especially reaching as high as 8.6% creep strain. This remarkable improvement in creep ductility is unlikely to arise from the altered grain structure and grain boundary precipitates induced by LaB6 but predominantly arises from the synergistic effect of P and B in enhancing resistance to crack propagation during the third stage of creep. [ABSTRACT FROM AUTHOR]

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Symmetrical biaryl compounds are vital chemical feedstocks in the fine chemical industry. Homocoupling, which produces aryl‐aryl reagents, remains the predominant method for their synthesis. Previously, Yaghi et al. reported a patent demonstrating the high performance of HKUST‐1 in homocoupling reactions involving arylboronic acids with electron‐withdrawing substituents. However, reactions with electron‐donating substituents yielded lower results. In this study, we introduce optimized protocols for HKUST‐1 catalyzed homocoupling of arylboronic acids with electron‐donating substituents, achieving symmetrical biaryl products with yields up to 93 %. We also observed significant hydroxylation byproducts competing with homocoupling products when the reaction was exposed to air, especially for arylboronic acids with electron‐donating substituents. This heterogeneous HKUST‐1 catalyst demonstrated recyclability for up to three cycles without a significant decline in catalytic activity. [ABSTRACT FROM AUTHOR]

Sterically loaded, anionic pyridine has been synthesized and utilized successfully in the stabilization of a isoleptic series of coinage metal complexes. The treatment of [4‐(Ph3B)‐2,6‐Trip2Py]K (Trip=2,4,6‐iPr3C6H2) with CuBr(PPh3), AgCl(PPh3) or AuCl(PPh3) (Py=pyridine) afforded the corresponding [4‐(Ph3B)‐2,6‐Trip2Py]M(PPh3) (M=Au, Ag, Cu) complexes, via salt metathesis, as isolable, crystalline solids. Notably, these reactions avoid the facile single electron transfer chemistry reported with the less bulky ligand systems. The X‐ray structures revealed that they are two‐coordinate metal adducts. The M−N and M−P bond distances are longest in the silver and shortest in the copper adduct among the three group 11 family members. Computational analysis revealed an interesting stability dependence on steric bulk of the anionic pyridine (i. e., pyridyl borate) ligand. A comparison of structures and bonding of [4‐(Ph3B)‐2,6‐Trip2Py]Au(PPh3) to pyridine and m‐terphenyl complexes, {[2,6‐Trip2Py]Au(PPh3)}[SbF6] and [2,6‐Trip2Ph]Au(PPh3) are also provided. The Au(I) isocyanide complex, [4‐(Ph3B)‐2,6‐Trip2Py]Au(CNBut) has been stabilized using the same anionic pyridylborate illustrating that it can support other gold‐ligand moieties as well. [ABSTRACT FROM AUTHOR]

A cationic copper‐stabilized coppoborylene was prepared and structurally characterized via infrared photodissociation spectroscopy and density functional theory calculations. This structure exemplifies a new class of borylenes stabilized by three‐center‐two‐electron metal‐boron‐metal covalent bonding interaction, displaying exceptional σ‐acidity and unparalleled π‐donor capability for CO activation that outperforms all of the known transition metal cations and is comparable or even superior to the documented base‐trapped borylenes. Its neutral form represents a monovalent boron compound with a strongly reactive amphoteric boron center built on transition‐metal‐boron bonds, which inspires the design and synthesis of new members of the borylene family. [ABSTRACT FROM AUTHOR]

Boron difluoride (BF2) complexes with asymmetrical N,N'‐bidentate ligands have received increasing attention due to their fascinating properties and broad applications. They are generally constructed in two steps: ligand formation, followed by boron complexation. This review focuses on categorizing these BF2 complexes based on the key synthetic strategies that have been applied in the ligand formation steps. The post‐functionalization, properties and applications of different types of BF2 complexes are presented. Their challenges and opportunities are also discussed. This should help the future rational design and synthesis of BF2 complexes with intriguing properties and practical applications. [ABSTRACT FROM AUTHOR]

AbstractPure and boron modified Ag3PO4 powders with different boron contents (0–5 wt.%) were prepared. XRD, ATR-FTIR, XPS, SEM-EDX, UV-Vis DRS and PL analyses were conducted for the characterization of the prepared powders. Characterization studies indicated the reduction in the band gap energy, the presence of boron and no change in the morphology due to boron modification. The results of photocatalytic experiments showed that boron modification increased the activity of Ag3PO4. The UV light dye degradation efficiency increased from 63% to 84% for methyl orange (MO) and from 41% to 65% for methyl red by 3% boron modification. The reaction rate constant for MO increased by a factor of 1.7. Under visible light, the activity was similarly enhanced by boron modification. The photocatalytic degradation efficiency increased from 31% to 58% and the reaction rate constant increased by a factor of 2.3 by boron modification for MO under low intensity visible light. These results showed that boron modification enhanced the photocatalytic dye degradation activity of Ag3PO4 under both UV and visible light. This enhancement was attributed to the decrease in the band gap energy and the increase in the interaction of the dye molecules with the photocatalyst surface through boron species. [ABSTRACT FROM AUTHOR]

Senescence is a cellular response having physiological and reparative functions to preserve tissue homeostasis and suppress tumor growth. However, the accumulation of senescent cells would cause deleterious effects that lead to age‐related dysfunctions and cancer progression. Hence, selective detection and elimination of senescent cells are crucial yet remain a challenge. A β‐galactosidase (β‐gal)‐activated boron dipyrromethene (BODIPY)‐based photosensitizer (compound 1) is reported here that can selectively detect and eradicate senescent cells. It contains a galactose moiety connected to a pyridinium BODIPY via a self‐immolative nitrophenylene linker, of which the photoactivity is effectively quenched. Upon interactions with the senescence‐associated β‐gal, it undergoes enzymatic hydrolysis followed by self‐immolation, leading to the release of an activated BODIPY moiety by which the fluorescence emission and singlet oxygen generation are restored. The ability of 1 to detect and eliminate senescent cells is demonstrated in vitro and in vivo, using SK‐Mel‐103 tumor‐bearing mice treated with senescence‐inducing therapy. The results demonstrate that 1 can be selectively activated in senescent cells to trigger a robust senolytic effect upon irradiation. This study breaks new ground in the design and application of new senolytic agents based on photodynamic therapy. [ABSTRACT FROM AUTHOR]

In the quest for effective photocatalysts for hydrogen production via photocatalytic water splitting, ZnIn 2 S 4 has garnered considerable attention due to its high photocatalytic hydrogen evolution capability. In this study, boron-doped ZnIn 2 S 4 was successfully synthesized via a hydrothermal method, with a small amount of cobalt phosphate (Co-Pi) decorated on its surface. The hydrogen evolution rate of boron-doped ZnIn 2 S 4 was determined to be 5.2 mmol g−1 h−1, surpassing that of pure ZnIn 2 S 4 by 1.68 times. Moreover, with the addition of Co-Pi to boron-doped ZnIn 2 S 4 , the hydrogen production rate escalated to 29.7 mmol g−1 h−1, which is 9.58 times higher compared to pure ZnIn 2 S 4. UV–vis analysis revealed that boron doping introduced new energy levels into ZnIn 2 S 4 , effectively narrowing the bandgap and enhancing light absorption wavelength range. Furthermore, PL and XPS analyses indicate that Co-Pi effectively captures photogenerated holes (h+) in ZnIn 2 S 4 , retaining photogenerated electrons and overcoming the disadvantage of electron-hole pair recombination in ZnIn 2 S 4. The doping and loading of Co-Pi as a cocatalyst ultimately contribute to enhancing hydrogen production efficiency, thereby significantly improving the photocatalytic hydrogen evolution capability of ZnIn 2 S 4. This study provides a scalable idea for designing composite catalysts in which doping and co-catalysts work together. • ZnIn 2 S 4 (ZIS) was synthesized hydrothermally using ZnCl 2 , In(NO 3) 3 ·xH 2 O, and thioacetamide (TAA) as precursors. • Defective ZnIn 2 S 4 (B-ZIS) was hydrothermally synthesized from ZIS and NaBH 4. • B-ZIS-CP composites were prepared through the in situ photodeposition of cobalt phosphide (Co-Pi) onto B-ZIS. • The composite catalysts exhibited exceptional photocatalytic activity for hydrogen evolution. • B-ZIS-CP demonstrates remarkable separation efficiency of photogenerated electron-hole pairs. [ABSTRACT FROM AUTHOR]

Adsorption isotherm and kinetic models are essential in predicting the adsorption mechanisms, which helps in boron (B) recommendation at appropriate doses. This study is formulated with the objective of assessing different kinetic and adsorption models for the adsorption of B in different soil orders (Entisol, Alfisol, Inceptisol and Vertisol) in Oil Palm plantations in India. The B adsorption in soils followed the order: Vertisol > Alfisol > Inceptisol > Entisol. The results revealed that, the Langmuir adsorption model fitted well for alfisol (part1 R2 = 0.9912 & part2 R2 = 0.9678), entisol (R2 = 0.9862) and inceptisol (R2 = 0.9924), while the Freundlich model fitted well for vertisol (R2 = 0.9943). The soils under entisol and inceptisol showed linear isotherms whereas, the vertisol and alfisol had curvilinear isotherms and the split Langmuir isotherm was worked out. High bonding energy at the lower part of split isotherm represented stronger retention of B at lower B concentrations. The B equilibrium was attained in 24 h in alfisol and inceptisol, and 12 h in entisol, whereas in vertisol, the equilibrium was not completed until 72 h. From the correlation coefficients obtained from all models, the pseudo-second-order kinetic model explained the B sorption in a better way followed by elovich and power function kinetic models in different soil types. Desorption of B is higher in entisol in most of the added B concentrations. The study suggests a higher rate of B fertilizer application than the recommended in soils having high B adsorption capacity for optimum crop growth and yield. [ABSTRACT FROM AUTHOR]

Fluorination of azopyridine N-donors regulates the formation of either B ← N coordination adducts or a co-crystal with phenylboronic acid catechol ester. Specifically, the formation of B ← N adducts is promoted by azopyridines with up to four fluorines, while perfluorination affords a co-crystal via phenyl–perfluoropyridyl [π⋯πF] contacts. Electrostatic potential maps showed supramolecular bonding competition outcomes to be primarily determined by modulation of electron-donating capacity and π surfaces of azopyridine N-donors using fluorination. [ABSTRACT FROM AUTHOR]

Curcuminoid boron difluoride dyes have garnered significant attention in the realm of bioimaging, primarily owing to their excellent photophysicochemical properties. However, the strong hydrophobicity limits their optimal near-infrared (NIR) fluorescence emission, and the synthesis process is complicated. In this study, Curc-TPA, a curcuminoid boron difluoride derivative with a high fluorescence quantum yield, was facilely synthesized and surprisingly exhibited aggregation-induced NIR emission in a dimethyl sulfoxide/water mixture. The compound self-assembled into stable and homogeneous nanoparticles through hydrophobic interaction with the amphiphilic polymer 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol), which showed enhanced aggregation-induced emission (AIE) capacity in the NIR region. The nanoparticles specifically enriched at the tumor site due to the enhanced penetration and retention effect and exhibited bright fluorescence in vitro and in vivo. Notably, they showed satisfactory hematological compatibility and unobservable cellular and histological toxicity. Therefore, they are of promising clinical significance in the AIE-enhanced NIR fluorescence imaging-visualized precise diagnosis of cancer. [ABSTRACT FROM AUTHOR]

The effect of carbon contamination on the elemental beta boron (β-B) from the graphite components of spark plasma sintering (SPS) was investigated. The X-ray diffraction, analytical electron microscopy (AEM) and Raman spectroscopy witnessed boron carbide (B 13+x C 2-x where x=0.05–0.35), when SPS temperature was above 1750 °C. The degree of carbon contamination became severe with increasing SPS temperature to 1800 °C and 1850 °C and formed a single-phase rhombohedral boron carbide with about 12 wt% of carbon. Our observations indicate that the carbon gets kinetically trapped into β-B to form boron carbide with a primitive unit cell consisting mainly of icosahedral B 11 C and three-atom chain of CBB configurations. After 6 months of natural aging, it has been revealed that boron carbide formed at and below sintering temperatures of 1800 °C is not a thermodynamically stable phase, and transformed reversibly to β-B structure. X-ray photoelectron spectroscopy ascertained that there are no longer B-C bonds and the existence of more C C bonds in a 6 months aged specimen, suggesting carbon is no longer strongly bonded to boron, but precipitates as graphitic structure. Further examination using atom probe tomography and AEM confirmed the existence of carbon nanoclusters within grains and high concentration of carbon segregating onto grain boundaries. The phase transformation of boron carbide to mostly boron resulted in a significant loss of hardness and modulus in a bulk SPS specimen. This study underscores the importance of solid solution and local bonding environment in icosahedral boron-rich solids for phase stability and sustained properties. [ABSTRACT FROM AUTHOR]

We report herein an effective method for an iron‐catalyzed vinylogous Michael addition of BODIPY derivatives to para‐quinone methides under mild conditions. The corresponding BODIPY‐derived diarylmethane compounds were obtained in 65–93 % yields. This method is featured by its inexpensive catalyst, simple reaction condition and broad substrate scope. [ABSTRACT FROM AUTHOR]

gem‐Diborylalkanes are highly valuable building blocks in organic synthesis and pharmaceutical chemistry due to their ability to participate in multi‐step cross‐coupling transformations, allowing for the rapid generation of molecular complexity. While progress has been made in their synthetic metholodology, the construction of β‐tertiary and C(sp3)‐rich gem‐diborylalkanes remains a synthetic challenge due to substrate limitations and steric hindrance issues. An approach is presented that utilizes synergistic photoredox and copper catalysis to achieve efficient C(sp3)−C(sp3) cross‐coupling of alkyl N‐hydroxyphthalimide esters, which can easily be obtained from alkyl carboxylic acids, with diborylmethyl species, providing a series of C(sp3)‐rich gem‐diborylalkanes with 1°, 2°, and even 3° β positions. Furthermore, this approach can also be applied to complex medicinal compounds and natural products, offering rapid access to molecular complexity and late‐stage functionalization of C(sp3)‐rich drug candidates. Mechanistic experiments revealed that diborylmethyl Cu(I) species participated in both the photoredox process and the key C(sp3)−C(sp3) bond‐forming step. [ABSTRACT FROM AUTHOR]

In this study, the new data concerning the electronic and vibrational properties of the BsO2i* defect in Czochralski‐grown boron‐doped silicon are reported. In silicon subjected to treatment at elevated temperatures, a new boron‐related defect is detected. An additional intracenter electronic transition for boron associated with the revealed defect is observed. The defect is identified as BsO2i due to the linear dependence of its formation efficiency on the boron content and the quadratic dependence on the oxygen concentration. The revealed complex is formed synchronously with the annealing of the previously identified BsO2i* defect. The detected complex is formed as a result of temperature transformation of the atomic configuration of the BsO2i* defect. The transformation occurs with activation energy of 2.59 eV. The local vibrational modes associated with both configurations of the BsO2i* complex are identified. The results of the study suggest that the BsO2i* defect in both configurations exists in a  wide temperature interval, impacts the optical and electronic properties of the material, and must be taken into consideration when developing Si:B‐based devices. [ABSTRACT FROM AUTHOR]

A mild Pd-catalyzed three-component cascade cyclization functionalization of o-iodostyrenes, internal alkynes and boron reagents is presented. The transformation is driven by a controlled reaction sequence of intermolecular carbopalladation, intramolecular Heck-type cyclization, and a borylation process to give versatile boryl-functionalized indene skeletons in a selective fashion. Significantly, (Bpin)2, (Bneop)2 and CH2(Bpin)2 as boron sources are all tolerated. Additionally, the synthetic utility of this approach is demonstrated by gram-scale synthesis and synthetic transformations. [ABSTRACT FROM AUTHOR]

In this paper, a series of B doped Ni/MgAl 2 O 4 catalysts for hydrogen production via steam reforming of methane (SRM) were prepared, and their catalytic activities and stability were evaluated. The characterization of XRD, XPS, TPR, BET, TPO, and TEM revealed that the addition of B could promote Ni dispersion, which lead to the reduce of Ni particle size. 0.5 wt% B was incorporated into Ni/MgAl 2 O 4 would increase Ni particle dispersion rate from 11.2% to 14.8%, which caused Ni particle average size was decreased from 8.78 to 6.96 nm. At the same time, 0.5% B doped would increase the chemisorbed oxygen content of the catalyst, and more oxygen vacancies were formed. Thus, Ni particles sintering and carbon deposition during SRM was suppressed, and the catalytic activity and stability were promoted. Ni-B 0.5 /MgAl 2 O 4 could achieve 90.2% methane conversion rate and 85% H 2 yield under 700 °C with a WHSV of 36,000 mL·(gh)−1 during SRM process, and only a marginal reduction (2%) of methane conversion rate was observed after 48 h reaction. The total carbon content on the used Ni-B 0.5 /MgAl 2 O 4 catalyst was approximately 0.031 g c ∙g cat −1, which was three times lower than that of Ni/MgAl 2 O 4. However, the excess B doping into Ni/MgAl 2 O 4 had a negative effect on the catalytic activity and stability. • 0.5 wt% B was incorporated into Ni/MgAl 2 O 4 would increase Ni particle dispersion rate from 11.2% to 14.8%. • 0.5 wt% B was incorporated into Ni/MgAl 2 O 4 would decrease Ni particle average size from 8.78 to 6.96 nm. • 0.5 wt% B was incorporated into Ni/MgAl 2 O 4 would increase oxygen vacancies. • Ni-B 0.5 /MgAl 2 O 4 could achieve 90.2% methane conversion rate and 85% H 2 yield under 700 °C. • Methane conversion rate was only decreased by 2% after 48 h SMR. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Recent advances in transition metal‐catalyzed o‐carborane B—H activation have led to the rapid development of various methodologies for cage boron functionalization. For catalytic cage B—H acyloxylation, intermolecular oxygenation gave products with different regioselectivities (B(3)‐, B(4)‐, and B(8,9)‐selectivities). Herein, an efficient palladium‐catalyzed direct cage B(4)–H oxygenation of o‐carboranylacetic acids has been achieved, where the carboxylic group serves as not only a directing group, but also a coupling partner. A wide range of substituted o‐carboranylacetic acids have been cyclized via the formation of B(4)−O bond to give the corresponding γ‐lactones in modest to excellent yields. A Pd(IV) intermediate is proposed to be involved in the catalytic cycle. This work offers valuable references for the BH/OH dehydrocoupling reactions under mild conditions to produce carborane‐featuring functional molecules. [ABSTRACT FROM AUTHOR]

Rapid accumulation of boron (B) leads to toxicity in plant tissues, and the narrow gap between deficiency and toxicity makes it difficult to adjust essential B levels in soil for plant productivity. Therefore, understanding different aspects of B tolerance is necessary to provide new and valid solutions to B toxicity. Gypsophila perfoliata stands out as a remarkable example of a B‐tolerant plant, with a natural propensity to thrive in environments such as B mines and soils enriched with high levels of B.In this study, a yeast functional screening experiment was conducted using cDNA libraries from G. perfoliata leaf and root cells for B tolerance.Ten colonies from the leaf library grew in 80 mm boric acid, while none emerged from the root library. Analysis of isolated cDNAs showed identical sequences and a unique motif related to B tolerance. The gene GpEF1A was identified in the tolerant yeast colonies, with predicted structural features suggesting its role, and RT‐qPCR indicating increased expression under B stress.A regulatory role for EF1A lysine methylation was proposed in mammalian cells and fungi because of its dynamic and inducible nature under environmental constraints. This could also be relevant for plant cells, as the high similarity of the GpEF1A gene in some salt‐tolerant plants might indicate the upregulation of EF1A as a conserved way to cope with abiotic stress conditions. This report represents the first instance of involvement of GpEF1A in B tolerance, and further detailed studies are necessary to understand other components of this tolerance mechanism. [ABSTRACT FROM AUTHOR]

The yields realized under rice-wheat rotation are generally low in the geographical regions prone to B deficiency and a sound B application schedule recommendation is required for the sustainable yields and enhanced soil fertility. The effect of different B application schedules involving different dosages and frequency of B application was investigated on yields and B nutrition of rice-wheat rotation and changes in the chemical fractions of B in soil in six years field study carried out on a sandy loam (Typic hapludoll). Based on the average grain yields of rice and wheat during the period of experimentation, application of 1.5 kg B as borax ha−1 to rice crop on alternate years was the profitable practice for mollisols as it gave an average yearly production of 5.51 t of rice grain and 4.28 t of wheat grain ha−1. The average concentration of B in flag leaves and grains of rice was much lower compared to wheat crop. The recommended schedule of B application to rice-wheat rotation resulted in a Benefit: Cost ratio of 11: 1 and also maintained the optimum level of B in soil. Most of the added B markedly increased specifically bound (0.05 M KH2PO4 extractable), ammonium oxalate (pH 3.3) extractable fractions followed by residual and organically bound fraction in the soil. [ABSTRACT FROM AUTHOR]

Both phosphorus (P) and boron (B) can interact with each other due to their similar properties and P can hinder the uptake of boron by plants. In this study, the effect of P and B concentrations on the growth of rice, sunflower, and maize plants grown under greenhouse conditions in an environment that would induce boron toxicity was investigated. To create a toxic environment, 40 mg kg−1 B was applied to rice plants, and 30 and 25 mg kg−1 B were applied to sunflower and maize plants, respectively. To alleviate the toxicity, 500 mg kg−1 P was added to the respective pots. The results of the study showed that B application reduced the fresh and dry weight of all plant species, while significant increases were observed with the addition of P. Among the applied P sources, TSP was found to be more effective than H3PO4 in terms of fresh and dry weight of maize plants. Plant-B concentrations increased with B application but were significantly reduced by the applied P sources, with no difference observed among the P sources. Plant-P concentrations, which decreased with B applications, increased as a result of P applications. In particular, H3PO4 was found to be more effective than TSP in terms of plant-P concentration, especially in sunflower and maize plants. This study determined that P fertilization can be beneficial in reducing the damage caused by boron toxicity, which is a stress factor that severely limits agricultural production in regions with arid and semi-arid climates. [ABSTRACT FROM AUTHOR]

Aiming to address the Mo volatilization problem of super-austenitic stainless steel at high temperature, the S31254 steel containing B and rare earth element Y with high oxidation resistance was designed. It was observed that a synergy of B + Y can promote the formation of the dense Cr2O3 layer at 1050 and 1100 °C, making MoO3 layer formation difficult. While the oxide layers of the 0B sample from top to bottom were divided into four layers: Fe-rich oxide layer, MoO3 layer, Cr–Mn–Ni spinel oxide layer, and Cr2O3 layer (loose and porous), thus the undense Cr2O3 layer in the 0B sample can hardly inhibit MoO3 volatilization, especially at 1100 °C. In addition, the synergistic effect of B and Y on the diffusion of Cr to the surface was calculated using first-principles calculations. The results demonstrated that both the addition of B and Y can enhance Cr diffusion to the surface, while Y can specifically promote the combination of Cr and O. Consequently, the combined presence of B and Y exhibits a more favorable synergy for improving the density of the Cr2O3 layer, effectively inhibiting MoO3 formation and volatilization, thereby enhancing the oxidation resistance of S31254. [ABSTRACT FROM AUTHOR]

Boron toxicity in arid and semi-arid soils is principally due to the high concentration of boron in irrigation water. This study aimed to investigate the effect of activated carbon on the concentration and distribution of boron in different plant organs, a factorial experiment in a completely randomized design under greenhouse conditions. Treatments included plant type (tomato and eggplant), activated carbon at four levels (zero, 1, 2 and 3%) and boron at three levels (zero, 2.5 and 5 mg L−1). The experiment was conducted with 24 experimental treatments in three replications and a total of 72 experimental units. The results showed that increasing levels of boron in irrigation water increased the concentration of boron in different organs of plants. With study the interactions between plant type, different levels of boron and activated carbon, it was found that application of activated carbon at higher levels of boron in irrigation water had more effect on reducing the boron concentration in tomato leaf. Adding 3% of activated carbon to 5 mg boron per liter of irrigation water reduced boron concentration in tomato leaf by 65% compared to control. The results show the efficacy of using activated carbon in reducing boron toxicity in plants in high concentrations of boron in irrigation water. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of H‐ and MeO‐ functionalized alkali metal hypersilyl borates. Consequently, two distinct silanides were used as polysilane frameworks for our chemical manipulations. Tris(silyl)silanide (1) and tris(trimethoxysilyl)silanide (2) react in the same manner with the BH3 ⋅ SMe2 complex to obtain two new alkali metal hypersilyl borates [(R3Si)3SiBH3M (M=alkali metal; R=H, (3), R=MeO, (4 a–c))] in good to excellent yields. NMR spectroscopy for all compounds and single‐crystal X‐ray crystallography for 3 and 4 a, b enabled a clear structural characterization. Single crystal X‐ray analysis of 3 showed a dimeric structure, where two THF‐molecules and three hydrides from the BH3‐group contribute to the coordination sphere of the lithium atom. Interestingly, crystals suitable for X‐ray analysis of 4 a and 4 b showed a solvent‐free cluster formation, due to the coordination of the MeO groups. Both species form coordination polymers with different coordination modes depending on the nature of the alkali metal. Attempted hydride abstraction reactions of 3 and 4 with various reagents under the formation of the free boranes proceeded unselectively. [ABSTRACT FROM AUTHOR]

Background: Borolatonin is a potential therapeutic agent for some neuronal diseases such as Alzheimer's disease (AD). Its administration exerts ameliorative effects such as those induced by the equimolar administration of melatonin in behavioral tests on male rats and in neuronal immunohistochemistry assays. Objective: In this study, motivated by sex differences in neurobiology and the incidence of AD, the ability of borolatonin to induce changes in female rats was assessed. Methods: Effects of borolatonin were measured by the evaluation of both behavioral and immunohistopathologic approaches; additionally, its ability to limit amyloid toxicity was determined in vitro. Results: Surprisingly, behavioral changes were similar to those reported in male rats, but not those evaluated by immunoassays regarding neuronal survival; while pro‐brain‐derived neurotrophic factor (BDNF) immunoreactivity and the limitation of toxicity by amyloid in vitro were observed for the first time. Conclusion: Borolatonin administration induced changes in female rats. Differences induced by the administration of borolatonin or melatonin could be related to the differences in the production of steroid hormones in sex dependence. Further studies are required to clarify the possible mechanism and origin of differences in disturbed memory caused by the gonadectomy procedure between male and female rats. [ABSTRACT FROM AUTHOR]

It is important to utilize the raw colemanite (RC) mineral, which has abundant reserves in the world, and to reduce its particles to smaller sizes for nanotechnology. However, not only the particle size of the produced colemanite powder but also its other properties need to be elucidated. By using the Taguchi design, the RC mineral was ground in a high-energy ball mill. From signal-to-noise (S/N) ratio, the smallest average particle size was found to be 3.10 µm for the experiment E04/nano-sized amorphous colemanite (NAC) powder. The characteristics of as-received RC mineral and synthesized NAC material were investigated using laser particle size analyzer, optical microscopes, SEM–EDS, XRD, TEM, HRTEM, and TGA–DTA devices. It was found that the NAC powder was not homogeneous, a small peak within the 300–20 nm range appeared, and d90, d50, d10, and dmin values were, respectively, 14.6 µm, 3.08 µm, 232 nm, and 26 nm. In the XRD analysis, the pure colemanite, calcite, and silica minerals were determined. The crystal structure of the NAC powder almost turned amorphous, and the crystallite size of (031) peak was reduced to 7.3 nm. It was deduced that the average particle size was 8.29 nm (R2 = 0.86), and the d-spacing value was 0.307 nm. This significant finding was attributed to the mobility of balls and moreover it was interpreted with an equation. An unknown transition in TGA–DTA was referred to the calcite mineral. Finally, it is believed that the synthesized NAC material will be beneficial to engineering studies as a natural/mineral additive. [ABSTRACT FROM AUTHOR]