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To enhance the proportion of domestically manufactured Chinese pellets in the furnace, it is crucial to investigate the impact of calcium flux on the metallurgical characteristics of pellets and analyze the phase evolution behavior during the reduction process of medium‐silica fluxed pellets. This study examines the metallurgical properties of medium‐silica acid pellets and low‐basicity medium‐silica fluxed pellets produced in China. The results indicate that incorporating a small amount of calcium flux significantly enhances reducibility index (RI), reduces reduction swelling index, and lowers reductive degradation index (RDI+3.15 mm) for fluxed pellets. At a basicity level of 0.6, RI for medium‐silica fluxed pellets reaches 66.86%, while RDI−0.5 mm increases to 1.62% with increasing basicity levels. As pellet basicity increases, charge pressure drop (APmax) decreases, CaO content in silicate liquid phase within slag phase increases, and softening–melting zone widens, consequently leading to reduced solid‐phase particle content within pellets and increased fluidity within slag phase. [ABSTRACT FROM AUTHOR]

Numerous challenges persist in the smelting of vanadium–titanium magnetite using the blast furnace process. These challenges can be overcome by adopting the HIsmelt process, without the need for additional ore or enhanced slag operations. In this study, the effects of basicity and the MgO/Al2O3 ratio on slag viscosity and crystallization behavior are investigated through thermodynamic calculations and experiments. In the results, a decrease in slag viscosity with an increase in basicity and MgO/Al2O3 ratio is demonstrated. Notably, MgO/Al2O3 ratios have a minor impact on the viscosity and break temperature of the slag. With a TiO2 content of 40 wt% in the slag, perovskite phases are identified as the main equilibrium solid precipitates during the crystallization process under various basicity and MgO/Al2O3 ratios. As the slag temperature decreases further, the liquid phase content in the slag progressively decreases, reaching complete crystallization at 1159.0 °C. For industrial production, it is advisable to maintain the binary basicity of the slag within the range of 1.0–1.1, with the MgO/Al2O3 ratio around 0.6. Herein, the research findings contribute to a deeper understanding of the viscosity and crystallization behavior of HIsmelt titanium‐containing slag. [ABSTRACT FROM AUTHOR]

Co3Mo3N has been reported to have activity for the synthesis of ammonia surpassing that of industrial Fe catalysts under certain conditions. However, so far the research has largely focused on unsupported Co3Mo3N. We report a comprehensive study on the catalytic activity of Co3Mo3N when supported on two distinct MgO substrates. Our findings reveal that the method of MgO preparation plays a crucial role in influencing surface basicity. Remarkably, Co3Mo3N supported on single‐crystalline MgO demonstrates significantly enhanced catalytic activity, achieving a 162.0 mmol g−1metal h−1 rate. This surpasses the performance on commercial MgO support (41.2 mmol g−1metal h−1) and unsupported Co3Mo3N (15.0 mmol g−1metal h−1). While kinetic analyses show no substantial differences between the two supported catalysts, spectroscopic studies employing CO2 and N2 temperature‐programmed desorption (TPD) reveal a richer array of basic sites and adsorption/desorption phenomena on the single‐crystalline MgO support. These catalysts exhibit exceptional stability. The drastically reduced Co/Mo loading amounts in comparison to the bulk form, make the commercialization of Co3Mo3N catalysts more practical. [ABSTRACT FROM AUTHOR]

A series of novel Sn2+ doped boroaluminate glasses were prepared by the traditional melt quenching method in this work. Their glass network structure, luminescent properties, and mechanisms were studied in detail. The main framework of the glass network was dependent on the glass network former (B 2 O 3) and intermediate (Al 2 O 3), and was characterized by the 11B and 27Al NMR spectra. Broadband tunable blue-violet emissions ranging from 320 to 550 nm were realized by regulating the glass network structure through optical basicity. The quantitative relationship between optical basicity and emission/excitation peak positions and intensities, FWHM, and Stokes-Shift of this Sn2+-doped glass were revealed, according to which the luminescent properties of Sn2+ could be modulated and even predicted in the future. This work will enrich our understanding of the luminescent properties of Sn2+ ions and the variations of glass network structure, guiding the design of efficient and tunable luminescent boroaluminate glass. [ABSTRACT FROM AUTHOR]

The reaction mechanism for the formation of the pseudo‐silaazatriene 1 (LN(SiMe3)2−Si−N−Si(L)NSiMe3; L=PhC−(NtBu)2) by the reaction of 1 equivalent of bis‐silylene (LSi−SiL; L=PhC(NtBu)2) with 3 equivalents of azide Me3SiN3 has been explored at M06/def2‐TZVPP//BP86‐D3(BJ)/def2‐TZVPP level of theory. The reaction mechanism is guided by the high Lewis basicity of the silicon lone pair and the high Lewis acidic character of Si−N bonds, as well as by the high tendency to eliminate N2 from Me3SiN3. The first step of the reaction is the formation of [3+1] cycloaddition product (I1) by the synergetic interactions of the lone pair on the silylene silicon with the π* molecular orbital of Me3SiN3 which is majorly localized on the terminal nitrogen atom, and the donation of the σ‐type lone pair on the nitrogen atom connected to the SiMe3 group with the Si−N σ* orbital on silylene. The elimination of N2 from I1 results in the formation of pseudo‐silaimine intermediate I2 having a dicoordinated, monovalent nitrogen atom. The most favourable pathway involves the second addition of Me3SiN3 followed by N2 elimination resulting bis‐silaimine intermediate I4‐P2. The highly reactive lone pair on the dicoordinated, monovalent nitrogen atom can be coordinated to the Si−N σ* MO of the second silylene moiety resulting in Si−N bond formation and Si−Si bond cleavage. This step is similar to the SN2′ reaction where the incoming nucleophile and the leaving group are on the same side resulting in the formation of silaimine I5. Further, the [3+1] cycloaddition of one more molecule of Me3SiN3 followed by N2 elimination results in the formation of silaimine intermediate I7. I7 undergoes 1,3‐silyl migration leading to the final product 1. The lone pairs on di‐ and tricoordinated nitrogen centres of all the intermediates are stabilized by hyperconjugative interactions. The delocalized hyperconjugative interaction stabilizes the lone pairs in 1. [ABSTRACT FROM AUTHOR]

In this review, the principles of gas-phase proton basicity measurements and theoretical calculations are recalled as a reminder of how the basicity PA/GB scale, based on Brønsted–Lowry theory, was constructed in the gas-phase (PA—proton affinity and/or GB—gas-phase basicity in the enthalpy and Gibbs energy scale, respectively). The origins of exceptionally strong gas-phase basicity of some organic nitrogen bases containing N-sp3 (amines), N-sp2 (imines, amidines, guanidines, polyguanides, phosphazenes), and N-sp (nitriles) are rationalized. In particular, the role of push–pull nitrogen bases in the development of the gas-phase basicity in the superbasicity region is emphasized. Some reasons for the difficulties in measurements for poly-functional nitrogen bases are highlighted. Various structural phenomena being in relation with gas-phase acid–base equilibria that should be considered in quantum-chemical calculations of PA/GB parameters are discussed. The preparation methods for strong organic push–pull bases containing a N-sp2 site of protonation are briefly reviewed. Finally, recent trends in research on neutral organic superbases, leaning toward catalytic and other remarkable applications, are underlined. [ABSTRACT FROM AUTHOR]

To achieve low‐cost clean production in steelmaking plants, a low‐carbon double slag converter steelmaking process (LCDSP) with high dephosphorization efficiency, low lime consumption, and low CO2 emissions is focused on. The average lime consumption in LCDSP has decreased about 25.8%, which can reduce at least about 10.3 million m3 CO2 emissions per converter per year in the current steelmaking plant. The phosphorus enrichment properties of decarbonization slag with different basicities are comprehensively evaluated through LCDSP industrial experiments, mineralogy, and ion–molecule coexistence theory (IMCT). The increase of decarburization slag basicity (DSB) significantly improves the dephosphorization efficiency of molten steel. With increasing the DSB from 2.93 to 3.52, the typical morphology of the P‐rich phase extends from small pieces to long strips and then changes to block shapes with smooth edges. Finally, it forms a massive P‐rich phase with an area of more than 10 000 μm2 with a DSB of 3.80. The phosphorus enrichment properties of decarbonization slag with different DSBs evaluated using multiple perspectives show a consistent change trend. IMCT provides an accurate thermodynamic method for quantitatively predicting the phosphorus enrichment capacity in slag in two stages of LCDSP. [ABSTRACT FROM AUTHOR]

In order to apply and develop fluorine‐free slag in steelmaking, it is of great significance to study the effect of composition for fluorine‐free refining slag on the cleanliness of molten steel which affects its performance directly. The effect of composition of fluorine‐free refining slag with medium and high basicity on the contents of impurity elements for sulfur and oxygen, and characteristics of inclusions in SWRS82B hard wire steel, are investigated systematically. Sulfide capacity of refining slag is estimated based on the Royal Swedish Institute of Technology model. Dissolved oxygen content in molten steel equilibrated by refining slag is calculated based on Factsage software and classical thermodynamics. The calculated results are in good agreement with experimental results. The plasticity of inclusions at high temperature and low temperature is analyzed by phase diagram and Young's modulus calculation. The best cleanliness and inclusions of SWRS82B steel are obtained with slag composition of 53%CaO–19%SiO2–19%Al2O3–7%MgO, which has good melting characteristics. The impurity elements sulfur and oxygen in steel can be controlled for 26 and 19 ppm, respectively, and the average size of inclusions is 2.84 μm. [ABSTRACT FROM AUTHOR]

Reduction of friction and wear by lubrication is necessary to improve the efficiency and prolong the lifespan of industrial machinery. However, several aspects regarding the lubrication effects in additive-combined oil are still unresolved. This study focuses on the effects of combining zinc dialkyldithiophosphate (ZnDTP), molybdenum dithiocarbamate (MoDTC), and Ca sulfonate on the frictional behavior of poly-α-olefin 4 (PAO4) lubricant oils. Ball-on-disk friction tests demonstrated that the exclusive addition of high-base Ca sulfonate solution reduced friction and wear of the lubricating oil. When combined with ZnDTP and MoDTC, the friction coefficients of PAO with high-base and low-base Ca sulfonate are affected by competitive reactions on the sliding surface. Quartz crystal microbalance with dissipation monitoring measurements suggests that high-base Ca sulfonate forms a stronger adsorption film than low-base Ca sulfonate. Atomic force microscope observations confirmed that the addition of low-base Ca sulfonate reduced friction and wear, whereas high-base Ca sulfonate induced competitive reactions with ZnDTP and MoDTC. This study provides valuable insights into the effects of the combination of additives on the lubricity of PAO and their impact on friction and wear characteristics, which are valuable for the design of suitable lubricants for industrial machinery. [ABSTRACT FROM AUTHOR]

The following glass system 35Pb3O4- 60SiO2-(5-x) ZnO- xY2O3 (x = 0, 1, 2, 4, 5) mol.% is fabricated by the classic melt-quench method. Amorphous status was confirmed by XRD analysis techniques. Structure features were influenced by yttrium oxide doping like density(5.91 to 6.97 g/cm3), molar volume (47.39 to 41.22 cm3), oxygen packing density(17.88 to 14.99 cm3), internuclear distance and number of ions (0.69 to 3.7 × 1021). Linear and non-linear optical properties are taking place. The energy gap was found to be increased from 2.59 to 2.72 eV with supplying of yttrium ions until 5 mol.% while the index of refraction decreases from 2.55 to 2.51. The nonlinear susceptibility (χ(3)) and refractive (n2) index decrease with increased yttrium concentration and have the values 0.396 to 0.351 × 10–12 (esu), 5.85 to 5.28 × 10–12 (esu) respectively. Molar refraction (12.3 to 12.32 cm3/mol.), Metallization(0.36 to 0.362), Electronegativity (0.696 to 0.704), Transmission coefficient (0.679 to 0.682) and steepness (0.097 to 0.103) were increased while the Molar polarizability (12.03 to 10.43 Ao3), Reflection loss (0.64 to 0.638), electronic polarization (2.873 to 2.866), Optical Basicity (1.352 to 1.348) and Static, Dielectric constant decreased with introduced yttrium ions. The radiation shield protection parameters like LAC (0.702 and 0.909 cm−1), MFP (1.425 and 1.1 cm),ECS (3.41 × 10−25 and 3.56 × 10−25), ACS (1.07 × 10−23 and 1.23 × 10−25), Neff (3.48 × 1023 and 3.67 × 1023), Zeff (31.25 and 34.56), R (0.66 and 0.59) and FNRCS (0.099 and 0.123) are investigated the provided values at 0.5 MeV for ZPSY0 and ZPSY5 respectively. The results indicate that Y2O3 growing in the network of glass modifies and improves the quality of present glasses against gamma radiation and fast neutrons. The superior glass sample in the present study is ZPSY5 which has 5 mol.% of Y2O3. The ZPSY5 sample can be used as a γ shield or neutrons collide in nuclear applications. [ABSTRACT FROM AUTHOR]

The Lewis basicity of a μ3-oxo ligand for (μ3-O)[Rh(cod)]3(μ4-O)M (cod = 1,5-cyclooctadiene) complexes was controllable by metal species on the μ4-oxo ligand locating at the opposite site of the μ3-oxo ligand. Coordination of the μ3-oxo ligand of [(μ3-O){Rh(cod)}3(μ4-O){Au(PPh3)}][BF4] (1) to [Au(PPh3)]+ indicated sufficient Lewis basicity of the μ3-oxo ligand in 1 to form [{(Ph3P)Au}(μ3-O){Rh(cod)}3(μ4-O){Au(PPh3)}][BF4] (2). In contrast, the addition of Li+ to 1 induced elimination of the originally coordinated [Au(PPh3)]+ due to the weak Lewis basicity of the μ3-oxo ligand for (μ3-O){Rh(cod)}3(μ4-O)Li(THF)3, in which a pentanuclear species, [{(Ph3P)Au}(μ3-O){Rh(cod)}3(μ4-O){Li(THF)3}][BF4] (3), was assumed to be generated in situ before the dissociation of [Au(PPh3)]+. [ABSTRACT FROM AUTHOR]

Brønsted basicity is a fundamental chemical property featured by several kinds of inorganic and organic compounds. In this Review, we treat a particularly high basicity resulting from the mechanical entanglement involving two or more molecular subunits in catenanes and rotaxanes. Such entanglement allows a number of basic sites to be in close proximity with each other, highly increasing the proton affinity in comparison with the corresponding, non-entangled counterparts up to obtain superbases, properly defined as mechanically interlocked superbases. In the following pages, the development of this kind of superbases will be described with a historical perusal, starting from the initial, serendipitous findings up to the most recent reports where the strong basic property of entangled molecular units is the object of a rational design. Brønsted basicity can be greatly enhanced by the mechanical entanglement of two or more interlocked molecular subunits within catenanes and rotaxanes. Here, the authors discuss the development of such mechanically interlocked superbases, and outline challenges and opportunities for future directions of research. [ABSTRACT FROM AUTHOR]

Hexadentate poly-Lewis acids (PLA) based on the bowl-shaped tribenzotriquinacene (TBTQ) have been synthesised. The introduction of three n-propyl groups into the benzhydrylic positions of the TBTQ backbone has significantly increased the solubility of the subsequently derived compounds. Semi-flexible PLAs containing boron and aluminium were obtained by hydrometallation of the corresponding 2,3,6,7,10,11-hexaalkynyl-TBTQ. Other rigid hexadentate PLAs were synthesised by stannylation of the corresponding alkyne units with Me3SnNMe2 followed by tin-element exchange reactions. The Lewis acidity of these PLAs was investigated in host–guest experiments with pyridine. Further experiments with bidentate bases showed correlations between their flexibility, their Lewis basicity and the complexation behaviour towards the synthesised PLAs. Addition of bis((dimethylphosphino)methyl)dimethylsilane (BisPhos) to solutions of the rigid alkynyl PLAs led to the formation of 3 : 1 adducts. Single crystal X-ray diffraction was used to further elucidate the host–guest connectivtiy. In addition, a sixfold pnictogen-bonding donor was synthesised by tin-antimony exchange. [ABSTRACT FROM AUTHOR]

The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). Here, we synthesized a self‐folded lithium salt, lithium 2‐[2‐(2‐methoxy ethoxy)ethoxy]ethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1‐trifluoro‐N‐[2‐[2‐(2‐methoxyethoxy)ethoxy)]ethyl]methanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self‐folded structure and high T+ around 0.8. ii) For LiFEA, a Li−N bond (2.069 Å) is revealed by single crystal X‐ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase "self‐cleaning" function for an ultra‐thin and compact SEI. iii) Starting from LiFEA, an electron‐withdrawing sulfone group is introduced near the N atom. The distance of Li−N is tuned from 2.069 Å in LiFEA to 4.367 Å in LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self‐cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs. [ABSTRACT FROM AUTHOR]

The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). Here, we synthesized a self‐folded lithium salt, lithium 2‐[2‐(2‐methoxy ethoxy)ethoxy]ethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1‐trifluoro‐N‐[2‐[2‐(2‐methoxyethoxy)ethoxy)]ethyl]methanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self‐folded structure and high T+ around 0.8. ii) For LiFEA, a Li−N bond (2.069 Å) is revealed by single crystal X‐ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase "self‐cleaning" function for an ultra‐thin and compact SEI. iii) Starting from LiFEA, an electron‐withdrawing sulfone group is introduced near the N atom. The distance of Li−N is tuned from 2.069 Å in LiFEA to 4.367 Å in LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self‐cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs. [ABSTRACT FROM AUTHOR]

β‐fluorocarbanions have garnered considerable attention for their dual reactivity in nucleophilic processes and β‐fluorine elimination. In this study, a thorough computational analysis was conducted to explore the reactions of α‐(trifluoromethyl)styrenes with 2‐pyridones to delineate the factors determining protonation or defluorination pathways for the in situ generated β‐fluorocarbanions under varied basic conditions. Our findings illuminate the critical role of organobase basicity in steering the direction of the competitive protonation and β‐fluorine elimination reactions. We propose the use of pKaH values of organobases as a quantitative indicator for discerning the predominant reaction pathways. This provides an efficient approach to predict and control the reaction outcome, facilitating the deliberate design of reactions to leverage the unique reactivity of β‐fluorocarbanions in the realm of fluorine chemistry. [ABSTRACT FROM AUTHOR]

The use of experimental parameters to quantify solvent properties, for example in linear free energy relationships, is well established and several scales of solvent acidity, basicity and polarity/polarizability have been developed. The success of this approach raises questions of which molecular properties contribute to particular solvent parameters and whether these contributions are found in all parameters representing a particular solvent property. In the present study, Catalan's hydrogen bond basicity and acidity parameters, SB and SA, and Gutmann's acceptor number, AN, a measure of a solvent's Lewis acidity, are correlated with molecular properties derived from computational chemistry. The results are compared with the results of similar correlations with Kamlet and Taft's β and α Solvent Scales, Gutmann's donor number DN) and Abraham's B and A solute scales. The results show that measures of solvent basicity, SB, β and DN all correlate strongly with the partial charge on the most negative atom in the solvent molecule and the energy of the donor orbital and, in all cases, the parameter values for hydrogen-bonded solvents are anomalous. Abraham's B, a measure of solute hydrogen basicity, depends only on the partial charge on the most negative atom and there is no anomaly in the values for solutes that, in the pure state, form hydrogen-bonded liquids. Similarly, all measures of solvent acidity, SA, α and AN, and Abraham's A, a measure of solute hydrogen bond acidity, depend on the partial charge on the most positive hydrogen on the molecule. [ABSTRACT FROM AUTHOR]

In this study, a series of nickels supported on gamma alumina with a metal dosage ranging from 0.5 to 3 wt.% were prepared and employed as the catalysts. The effect of nickel dosage on material properties, reaction performance, and catalyst deactivation was investigated. At a low dosage, the nickel-free having low metal-support interaction contributed significantly to the total active site. The basicity of the material was enhanced along with the increase in nickel loading. The presence of active metal showed a great impact at the beginning leading to big improvements in feedstock conversion. However, beyond a nickel dosage of 2 wt.%, further additions did not noticeably influence the reaction performance. Regarding catalyst deactivation, different carbon species were observed on catalyst surface, depending on the nickel dosage. Catalysts with less than 2 wt.% nickel exhibited amorphous carbon as the dominant morphology on the spent catalyst. In contrast, catalysts with 2Ni/Al2O3 and 3Ni/Al2O3 compositions showed graphitic carbon as the main side product. These findings provide insights into the relationship between nickel dosage, catalyst properties, and catalytic performance in methane dry reforming. By understanding the effects of nickel loading on material properties and reaction behavior, researchers can optimize catalyst design and develop more efficient and stable catalysts for sustainable syngas production. [ABSTRACT FROM AUTHOR]

Converting carbon dioxide into value-added products is one of the most important inventions to solve global warming and energy demand. Herein, we prepared a series of Zr-doped CeO2 catalyst (Ce1Zrx, x = 0.01, 0.05 and 0.2) for the catalytic production of ethylene urea (EU) from ethylenediamine (EDA) and CO2. Several characterization techniques, such as XRD, FTIR, Raman, TEM, N2 adsorption, CO2-TPD and XPS, were used to investigate the relationship between catalytic activity and structural characteristics, especially the doping form and promotion mechanism of Zr in CeO2 lattice. The results present that the Ce1Zr0.01 catalyst revealed excellent catalytic activity with 91.5% EDA conversion and 100% EU selectivity and cyclic stability in comparison with undoped CeO2. The doped Zr was beneficial to the formation of enriched defects and led to more oxygen vacancies and weak basic sites, thus enhancing CO2 adsorption and activation. This work laid a foundation for the design of highly active catalysts for the synthesis of EU from CO2 and EDA. [ABSTRACT FROM AUTHOR]

For the lithium (Li) metal anode, constructing a strong and durable protective layer with lithium‐ion permeability is crucial, especially in high donor number (DN) solvent system. High DN solvent‐based electrolytes can support both higher capacity and lower charge overpotential in the rechargeable lithium–oxygen batteries (LOBs). However, Li anodes in high DN solvent system suffer from severe corrosion and uncontrolled dendrite growth due to the unstable solid‐electrolyte interphase (SEI). Typically, this interface is formed in situ through electrochemical processes with complicated component and spatial distribution. Here, a functional molecule is introduced to construct an ion‐wall (IW) on Li surface by prechemical sequential reactions (p‐CSRs), through which the crystalline nanoparticles as bricks and amorphous hybrid compounds as the mortar can be produced to build such a "wall." Different from the conventional SEI, this wall is not only compact and uniform, but also possess high strength, excellent passivation properties and high ionic conductivity. With these properties, the IW could suppress Li dendrites and inhabit the side reaction, supporting highly reversible Li plating/stripping behavior in high DN solvent system. As a result, the cycle stability of LOBs based on the IW protected Li anode is significantly improved. [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]

The effects of CaO/SiO 2 ratio (basicity) and CaCl 2 addition amount on the properties of CaO–MgO–Al 2 O 3 –SiO 2 –CaCl 2 glass-ceramics (GC) were investigated. When sintered at 825 °C, the increase in basicity from 0.35 to 0.75 reduced the porosity of GCs from 1.1 to 0.8 vol%, but the increase of CaCl 2 addition amount from 5 to 10 wt% increased the porosity from 0.8 to 7.0 vol%. The main crystalline phase of GC changed from augite (Ca(Mg 0 · 7 Al 0.3) (Si 1 · 7 Al 0.3)O 6) to Ca 10 Al 12 Cl 2 Si 5 O 37 by increasing the CaCl 2 addition amount to 7.5 wt%. The increase in CaCl 2 addition had adverse effects on the bending strength and Vickers hardness, while the rise in basicity deteriorated the bending strength but had little impact on the Vickers hardness. This study may have a guiding significance for preparing slag-based GCs and treating CaCl 2 -containing wastes. [ABSTRACT FROM AUTHOR]

Photocatalytic reactions involving a reductive radical‐polar crossover (RRPCO) generate intermediates with carbanionic reactivity. Many of these proposed intermediates resemble highly reactive organometallic compounds. However, conditions of their formation are generally not tolerated by their isolated organometallic versions and often a different reactivity is observed. Our investigations on their nature and reactivity under commonly used photocatalytic conditions demonstrate that these intermediates are indeed best described as free, superbasic carbanions capable of deprotonating common polar solvents usually assumed to be inert such as acetonitrile, dimethylformamide, and dimethylsulfoxide. Their basicity not only towards solvents but also towards electrophiles, such as aldehydes, ketones, and esters, is comparable to the reactivity of isolated carbanions in the gas‐phase. Previously unsuccessful transformations thought to result from a lack of reactivity are explained by their high reactivity towards the solvent and weakly acidic protons of reaction partners. An intuitive explanation for the mode of action of photocatalytically generated carbanions is provided, which enables methods to verify reaction mechanisms proposed to involve an RRPCO step and to identify the reasons for the limitations of current methods. [ABSTRACT FROM AUTHOR]

The adsorption of ethanol and ammonia changes the basic properties of alumina, and new basic sites are created. Ethanol reacts with surface Al-OH groups, forming ethoxy group Al-O-C2H5. The substitution of Al-OH by Al-O-C2H5 increases the negative charge of neighbouring oxygen atoms, and they became sufficiently basic to react with adsorbed CO2 forming carbonate species CO32−. These carbonates were found to be monodentate and bidentate species. Preadsorption of ammonia also increases the basicity of alumina, but the mechanism is different than for ethanol adsorption. Adsorbed ammonia interacts with surface Lewis acid sites being three-coordinated aluminium atoms. This interaction is accompanied by an electron transfer from ammonia molecules to surface sites, and increases the basicity of the neighbouring oxygens, which can react with the absorbed CO2. The carbonate species formed are polydentate ones. [ABSTRACT FROM AUTHOR]

The study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives is mainly influenced by LP(e) → σ∗ electronic delocalization effects, with the highest stabilization observed on the oxygen atom of the nitroxide moiety. This work also considers electron density, atomic charges, and energetic and thermodynamic properties of the studied NO radicals, and their relative stability. The proton affinity and gas-phase basicity of the studied compounds were computed at T = 298 K for O-protonation and N-protonation, respectively. The studied DFT method calculations show that O-protonation is more stable than N-protonation, with an energy difference of 16.64–20.77 kcal/mol (22.80–25.68 kcal/mol) at the B3LYP (M06-2X) method. The AIM analysis reveals that the N–O...H interaction in H2O complexes has the most favorable hydrogen bond energy computed at bond critical points (3, − 1), and the planar configurations of TEMPO derivatives exhibit the highest EHB values. This indicates stronger hydrogen bonding interactions between the N–O group and water molecules. [ABSTRACT FROM AUTHOR]

The deep separation between In(III) and Fe(III) ions is considered as an important technological challenge in the engineering fields. The In(III) ions are closer to the soft acid in terms of Lewis acidity due to the smaller polarizability and greater deformability than the Fe(III) ions, which facilitates the possibility of separating them. Herein, the Lewis basicity of the N‐containing adsorption sites is regulated by the fluorine‐containing group to better match with the In(III) ions rather than Fe(III) ions, causing a significant discrepancy in the binding of the adsorption sites to them. Moreover, targeted programmed desorption techniques based on the potential energy differences of the adsorption sites can achieve the deep separation of In(III) and Fe(III) ions, and reach an exceptional concentration of 20.7 mmol L−1 for In(III) ions in the initial desorption solution with extremely high mass ratio (mIn/mFe = 151.7). This work provides a novel technique for in‐depth separation of In(III) and Fe(III) ions from mixed systems, and a new strategy for separating metal ions with similar or close properties. [ABSTRACT FROM AUTHOR]

This study was intended to investigate the effects of basicity and oxygen partial pressure on the distribution behavior of Ni in the nickel smelting process using nickel oxide ore, the raw material of nickel, among natural ores. Experiments were conducted in a vertical tube furnace using Fe-Ni metal and FeO-MgO-SiO2 ternary slag, which simulated the composition of natural ore. An equilibrium experiment was conducted to observe the distribution ratio of Ni, and thermodynamic data required for this experiment was calculated through Factsage. As a result, it was found that as the oxygen partial pressure increased, the Ni content in the slag increased linearly. The Ni content in the slag increased as the basicity moved away from 0.60. [ABSTRACT FROM AUTHOR]

The spectroscopic characteristics of Er-doped lead silicate glasses were investigated with respect to the effects of glass modifiers (Li+, Na+, K+, Mg2+, Ca2+, Sr2+, and Ba2+)with various optical basicities. Using the absorption spectra of the glasses, the Judd--Ofelt parameters of the glasses were calculated and examined, with an emphasis on the glass emission intensity ratio at 1572 nm. The spectra of the samples at low temperatures were examined, and the Stark splitting of Er3+ was investigated. The McCumber method was used to determine the emission cross sections of glasses. The SPM glass exhibited high values of full width at half maximum (51.24 nm) and the emission cross section at 1572 nm (1.908 x 10-21 cm²), with potential applications for guiding component design of 1.5-μm fiber lasers and amplifiers. [ABSTRACT FROM AUTHOR]

In this article, the influence of the Fe2O3 addition amount on the dephosphorization kinetics of hot metal at the low slag basicity (CaO/SiO2) of about 1.6 and low temperature of 1623 K is investigated with laboratorial experiments and the kinetic model. Si and P contents in the hot metal during the whole dephosphorization process, and the endpoint FeO content in the slag, show good agreements between the calculated results with the kinetic model and experimental results. The peak value of dephosphorization rate linearly increases from 8.35 × 10−5 to 4.52 × 10−4 mass% s−1 when the weight ratio of Fe2O3 is increased from 5 to 10/100 g hot metal. With the increase in Fe2O3 addition amount, the mass transfer coefficient in the hot metal phase (km) and that in the slag phase (ks) and dephosphorization rate constant (k) all increase. The value of km is found to be 4.34 times that of ks. During the dephosphorization process, the rate‐controlling step converts from the mass transfer in slag phase to the mass transfer in hot metal phase in less than 10 min. With the increase in Fe2O3 addition amount, the value of interfacial oxygen activity of aO*$a_{\text{O}}^{\star}$ increases from 0.0102 to 0.0201. [ABSTRACT FROM AUTHOR]

This study investigates the effects of increasing PbO concentration on the Al2O3–PbO–B2O3–SiO2 glasses' physical, mechanical and gamma ray shielding properties. PbO addition leads to higher density and molar mass, making the glass denser. However, molar volume decreases, indicating a more compact structure. Interatomic distances and ion concentration change, strengthening atomic interactions. Oxygen molar volume increases, but packing density drops with more PbO, impacting the glass lattice. Optical basicity rises, suggesting improved electron transport and optical behavior. Electronegativity decreases, and electronic polarizability increases with higher PbO content, rendering the glass more electron-donating and sensitive to external electric fields.This study investigates glass mechanical properties using the Makishima–Mackenzie model. As PbO concentration rises, elastic moduli consistently decrease, signifying increased flexibility in glass structures. The mass attenuation coefficients (MAC) of the chosen glasses were evaluated in the 0.284–1.333 MeV energy range. It was found that increased PbO content leads to a corresponding MAC enhancement. The MAC values at 0.284 MeV were 0.297 and 0.349 cm2/g, while at 0.511 MeV they varied between 0.124 and 0.135 cm2/g. It was found that Glass Pb47.5 sample, which contains a higher amount of PbO compared to the other glasses, had the highest MAC at all energies. The results showed that the PbO has a notable impact on the MAC and thus on the radiation attenuation performance at lower energy. Moreover, increased glass density led to a corresponding LAC increase, which at 0.284 MeV increased from 1.269 cm−1 for Pb32.5 to 1.898 cm−1 for Pb47.5. According to the LAC results, one simple means of enhancing the glasses' radiation shielding properties is utilizing a high PbO percentage. This paper aims to illuminate silicate glasses' radiation shielding abilities. The paper will investigate the efficiency under specific conditions, like high-energy radiation. Moreover, it will explore innovative methods to enhance their shielding competence, concreting the way for a better yet effective radiation shielding approach. [ABSTRACT FROM AUTHOR]

We demonstrate herein a reported syntheses pathway for form unsubstituted boron subnaphthalocyanines (BsubNcs) since their discovery in 1995 and to avoid random bay-position halogenation. This was achieved through the use of triphenyl borates as the macrocyclic templating reagent avoiding the formation of random bay-position halogenated BsubNc by-products. We also outline a method to screen boron templating reagents by computing their Lewis acidity using the fluoride ion affinity method as well as the screening of the macrocyclic precursor by determining its Lewis basicity using a boron trifluoride affinity scale of various organic macrocyclic precursors in order to balance these parameters to enable macrocycle formation. We find that a balancing of these parameters enabled multiple methods for the synthesis of unsubstituted BsubNc. For this study, we isolated the axially fluorinated and axially pentafluorophenoxylated BsubNcs and characterize their photophysical and electrochemical properties as there was no random bay-position substitutions. For this study, we also demonstrated as a 'part 2' the versatility in the synthetic methods developed through the synthesis of boron subphthalocyanines (BsubPcs), other BsubNcs and a hybrid materials of BsubPc + BsubNc called Bsub(Pc3-p + Ncp). We also explored an industrially relevant synthesis method of triphenyl borates and found it to be successful in the processes outlined herein providing a potential route to improving the sustainability of this class of triphenyl borate materials. [ABSTRACT FROM AUTHOR]

The interplay of two proximate gallium centres equips the bimetallic complex CyL2Ga2 (1, CyL2 = 1,2-trans-Cy[NC(Me)C(H)C(Me)N(Dip)]2, Dip = 2,6-i-Pr2C6H3) with increased Lewis basicity and higher reducing power compared to the monometallic gallanediyl LGa (2, L = HC[MeCN(Dip)]2) as evidenced by cross-over experiments. Quantum chemical calculations were employed to support the experimental findings. [ABSTRACT FROM AUTHOR]

The influence of adding Cr(III) compounds into Zn−BEA zeolite samples (with silicate modulus Si/Al=17, 100, and 1000) on the redox and acid–base characteristics of Cr/Zn−BEA zeolites were studied, and their catalytic properties in propane dehydrogenation with CO2 to propylene. It was established (based on the XRD, low–temperature (77 K) ad/desorption of N2, TPR−H2, TPD−MSC−NH3(CO2), C3H8(C3H6), FTIR−Py data) that the acid–base characteristics of the surface of bifunctional Cr/Zn−BEA catalysts, namely the amount, strength, and nature (Lewis and Brønsted sites), determine their activity/selectivity, and operation stability in the process of CO2−PDH. This indicates that over Cr/Zn−BEA catalysts, the process runs along the route of direct propane dehydrogenation combined with the reverse water gas shift reaction. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation of nitriles is a green and efficient method to produce amines. However, it is still difficult to selectively obtain a specific amine. Herein, we report that a SiC supported highly dispersed Ni catalyst shows high performance for the hydrogenation of nitriles to corresponding primary amines without ammonia addition. Further studies reveal that the Ni/SiC catalyst has a high hydrogen spillover capacity; thus, the active H species dissociated on Ni can easily spill over to the SiC surface and react with the nitrile adsorbed and activated on SiC. Besides, the moderate basicity of Ni/SiC is also responsible for the increased selectivity of primary amines. This study provides a new idea and reference for designing selective nitrile hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Vanadium–titanium ore possesses significant mining and utilization value. The basicity of vanadium–titanium sinter has a direct impact on the formation, location, thickness, permeability, and heat exchange of the cohesive zone in the blast furnace. This paper investigated the influence of increasing the basicity of the sinter on the comprehensive burden's cohesive dripping properties in the blast furnace, while keeping the final slag basicity constant. This study was conducted through cohesive dripping property experiments. The findings indicated that as the sinter basicity in the comprehensive burden structure increased and the corresponding increase in the proportion of pellets occurred, the softening performance of the comprehensive burden improved, the cohesive zone became thinner, the lower edge of the cohesive zone shifted upward, and the softening melting properties became better in general. With an increase in the sinter basicity, the dripping difference pressure of the comprehensive burden decreased, and the dripping rate firstly increased and then decreased. An increase in the sinter basicity of the comprehensive burden structure promoted V reduction, and the V element yield and Cr element yield of the sinter were both increased; the optimal sinter basicity was 2.5, and the corresponding pellet proportion was 42%. [ABSTRACT FROM AUTHOR]

In steelmaking, the bottom‐blown O2‐CaO process is used to achieve efficient dephosphorization. However, few studies have applied it to dephosphorization converters. Therefore, this study considers the thermodynamic and kinetic mechanisms of dephosphorization during the process. The selective oxidation transfer temperatures of C and P are calculated. Compared to the combined blowing process, the bottom‐blown O2‐CaO process reduces the optimum dephosphorization temperature from 1593 to 1573 K. Moreover, the FeO content decreases by 20.7% owing to the increased stirring energy and improved kinetic conditions; the binary basicity (R) of the slag increases, and the lime consumption decreases by 2.9 kg t−1. The higher slagging efficiency indicates that the CaO powder melts and dephosphorization is completed during the fire‐spot zone floating process. Furthermore, the optimum FeO content for dephosphorization decreases as R increases. The selective oxidation of C and P can be divided into two stages. The oxidation stage of P preferred C is extended in this process. Overall, the end‐point P content accounts for 22.52% and 46.85% of the samples prepared using the combined blowing and bottom‐blown O2‐CaO processes when the P content is 0.02–0.03%, respectively. [ABSTRACT FROM AUTHOR]

SrO has attracted attention for its use as a heterogeneous catalyst in producing biodiesel from transesterification owing to its high alkaline character and low solubility in methanol. In studies conducted in this decade, reaction conditions such as the methanol–oil molar ratio, reaction time, catalyst loading and temperature have been optimized in these systems. Furthermore, several works have been carried out to improve the physicochemical properties and increase the leaching resistance of this material. Thus, the new trends in using SrO in transesterification reactions are that this oxide should be supported or combined with Al2O3, TiO2, ZrO2, or Fe2O3, CaO, metal–organic frameworks, zeolites or La2O3. It has been observed that strontium can form mixed crystalline phases with these oxides by increasing the (M2+O2−) pairs and Lewis basicity of the oxygens, resulting in increased basicity and catalytic activity. Moreover, the transition metal oxides may provide Lewis acidity. Hence, these strontium‐containing catalytic systems have demonstrated a bifunctionality that can perform esterification and transesterification reactions at the same time. In addition, the combination of these oxides decreases the leaching of the catalyst. Other materials such as metal–organic frameworks, zeolites, and La2O3 have been studied as SrO supports, showing that they can be used in oil transesterification reactions. [ABSTRACT FROM AUTHOR]

The glasses' density, molar volume, and molecular weight increase with increasing lead concentration for the PbO–Bi2O3–ZnO–B2O3 glasses. The ion concentration and field strength increase with increasing PbO concentration. Changes in the packing density and oxygen molar volume suggest network changes of a structural nature. The increase in optical basicity and decrease in electronegativity values indicate a higher electron-donating tendency of the glasses with increased concentration of PbO, while the increase in electronic polarizability suggests greater distortion susceptibility due to an externally located electric field. Makishima-Mackenzie's theory was used to study the outcome of lead oxide concentration on the glass's mechanical properties. The increase in PbO concentration results in increased network complexity and stiffness, together with elevated dissociation energy. However, this also results in a decrease in packing density and elastic moduli. The Poisson ratio decreases, indicating cross-linking in the glass network, and the fractal bond connectivity parameter indicates a three-dimensional network. The radiation shielding capability has been compared to other glasses as well and it is found that 70PbO–10Bi2O3–10ZnO–10B2O3 sample is a superior choice for radiation shielding glass. [ABSTRACT FROM AUTHOR]

A series of Fe-modified bimetallic hydrotalcite-like photocatalysts are prepared through co-precipitation containing amounts of M2+(NO 3) 2 ·6H 2 O (M2+ = Mg, Ni) and M3+(NO 3) 3 ·9H 2 O (M3+ = Al, Fe) with a fixed Ni content and a monometallic 25Ni/Al 2 O 3 catalyst for comparison purpose. The main objective of this experimental work is to study the replacement of Al with Fe in the photocatalyst on the CO 2 methanation performance under three different reaction conditions (dark, ultraviolet and visible illumination). Thus, the use of Fe as a promoter has been studied for improving the light adsorption capability of photocatalysts and the reducibility of active metals. However, the results showed that modification by Fe acting as active metal and as support modification, is less effective than modification by Al. Therefore, the effects of both the basicity and photothermal activation by plasmonic nanoparticles under ultraviolet and visible photocatalytic conditions improve the methane production compared to the reaction under dark conditions. [Display omitted] • Al3+ modification in the hydrotalcite enhances CO 2 conversion. • Basicity and photothermal activation under light improved methane production. • Under UV- and visible-light reaction T lowers up to 100 K. • Ni based hydrotalcite catalyst do not present deactivation during 16 h. [ABSTRACT FROM AUTHOR]

Ether‐based electrolytes have good compatibility for lithium metal, which is widely used in lithium metal batteries (LMBs). However, the electrolyte is not suitable for high voltage (>4.0 V) due to its poor anti‐oxidation behavior. Herein, an anion chemistry strategy is designed for a typical 1,2‐dimethoxyethane (DME)‐based electrolyte with 1 m lithium bis(fluorosulfonyl)imide (LiFSI), by using nitrate anion (NO3−) with a high donor number (DN) value to regulate the coordination of DME and FSI–. It is evidenced that the interaction between them is weakened due to the competitive advantage of NO3−, therefore a weakly solvating electrolyte is achieved. It promotes the formation of an inorganic‐rich passivation layer on the cathode and facilitates the de‐solvation process, thus it is suitable for high voltage even at 4.5 V. The anion‐regulated weakly solvating electrolyte (ARWSE) designed here is different from the high‐concentration electrolyte (HCE), localized HCE, and WSE which are of high cost and complexity. The ARWSE is demonstrated to be an adjustable electrolyte system, effectively improving the interfacial chemistry of LMBs. [ABSTRACT FROM AUTHOR]

Zeolite NaP1 was found to display the highest affinity for CO2 in preliminary modifications of coal fly ash-derived zeolites (4A, Y, NaP1 and X) by four amines (1,3-diaminopropane, N,N,N′,N′-tetramethylethylenediamine, Tris(2-aminoethyl)amine and ethylenediamine). In the second step, different fatty acid loaded NaP1 samples were prepared using palmitic, oleic and lauric acids. CO2 and H2O thermal programmed desorption (TPD) revealed changes in intrinsic basicity and hydrophilic character, expressed in terms of CO2 and H2O retention capacity (CRC and WRC, respectively). Infrared spectroscopy (IR), N2 adsorption-desorption isotherms and scanning electron microscopy allowed for correlating these changes with the type of interactions between the incorporated species and the zeolite surface. The highest CRC values and the lowest CO2 desorption temperatures were registered for NaP1 with the optimum content in palmitic acid (PA) and were explained in terms of the shading effect of surface acidity by the rise of basic Na+-palmitate salt upon cation exchange. The amine/fatty acid combination was found to paradoxically mitigate this beneficial effect of PA incorporation. These results are of great interest because they demonstrate that fatty acid incorporation is an interesting strategy for reversible CO2 capture. [ABSTRACT FROM AUTHOR]

The design of pyridine‐derived organocatalysts aims at the increase of their Lewis basicity, however such an approach is not always efficient. For example, strongly Lewis basic DMAP is completely inefficient as catalyst in the cyclopropanation reaction. Herein we disclose an alternative approach that relies on attenuation of DMAP Lewis basicity. Specifically, the replacement of 4‐dimethylamino substituent in DMAP for 4‐MeO group delivered a highly efficient catalyst for cyclopropanation of electron‐deficient olefins with α‐bromoketones. Kinetic studies provide compelling evidence that the superior catalytic efficiency of 4‐MeO pyridine (MOPY) is to be attributed to the favorable balance between Lewis basicity and leaving group ability. The use of chiral, enantiomerically pure MOPY catalyst has helped to achieve high enantioselectivities (up to 91 : 9 er) in the previously unreported pyridine‐catalyzed cyclopropanation reaction. [ABSTRACT FROM AUTHOR]

We have quantum chemically investigated the boron‐boron bonds in B2, diborynes B2L2, and diborenes B2H2L2 (L=none, OH2, NH3) using dispersion‐corrected relativistic density functional theory at ZORA‐BLYP‐D3(BJ)/TZ2P. B2 has effectively a single B−B bond provided by two half π bonds, whereas B2H2 has effectively a double B=B bond provided by two half π bonds and one σ 2p–2p bond. This different electronic structure causes B2 and B2H2 to react differently to the addition of ligands. Thus, in B2L2, electron‐donating ligands shorten and strengthen the boron‐boron bond whereas, in B2H2L2, they lengthen and weaken the boron‐boron bond. The aforementioned variations in boron‐boron bond length and strength become more pronounced as the Lewis basicity of the ligands L increases. [ABSTRACT FROM AUTHOR]

The DFT‐level computational investigations into Gibbs free energies (ΔG) demonstrate that as the dielectric constant of the solvent increases, the stabilities of [M(NH3)n]2+/3+ (n = 4, 6; M = selected 3d transition metals) complexes decrease. However, there is no observed correlation between the stability of the complex and the solvent donor number. Analysis of the charge transfer and Wiberg bond indices indicates a dative‐bond character in all the complexes. The solvent effect assessed through solvation energy is determined by the change in the solvent accessible surface area (SASA) and the change in the charge distribution that occurs during complex formation. It has been observed that the SASA and charge transfer are different in the different coordination numbers, resulting in a variation in the solvent effect on complex stability in different solvents. This ultimately leads to a change between the relative stability of complexes with different coordination numbers while increasing the solvent polarity for a few complexes. Moreover, the findings indicate a direct relationship between ΔΔG (∆Gsolvent‐∆Ggas) and ΔEsolv, which enables the computation of ΔG for the compounds in a particular solvent using only ΔGgas and ΔEsolv. This approach is less computationally expensive. [ABSTRACT FROM AUTHOR]

In our previous study, we elaborated a method of determination of concentrations of the basic sites O2− and OH− in a quantitative IR study of CO2 adsorption. Previous adsorption studies or TPD experiments only provided the total basicity without distinguishing between O2− and OH−. In this study, we determined the concentration of O2− and OH− on ZnO, Ga2O3, and MgO surfaces. The basicity of ZnO and MgO was found to be significantly higher than that of Ga2O3. The surface of ZnO was rich in O2−, the contribution of OH− was very small, and the Ga2O3 surface contained mainly OH−. For MgO, the contribution of O2− and OH− was comparable. According to the IR results, only a small fraction of all surface hydroxyls were sufficiently basic to react with CO2. The partial dehydroxylation changed the proportion of the concentrations of O2− and OH− on the oxides. We also elaborated upon a new method to determine the total concentration of basic sites via CO2 desorption monitored using IR. For all the oxides, we studied the sum of the concentrations of O2− and OH−, as determined in our quantitative IR studies, to find whether they were comparable with the total basicity determined in the desorption experiments. [ABSTRACT FROM AUTHOR]

This work investigates biodiesel production via transesterification of Mexican palm oil with methanol catalyzed by binary solid base core–shell catalysts with improved catalytic stability. A series of CaO–ZnO mixed solids were prepared using an inexpensive co–precipitation method by varying ZnO content from 5 to 20 mol%. Several factors, such as surface basicity, ZnO content, phase compositions, and thermal treatment of the catalysts, were all proven to be crucial for the production of biodiesel with good quality. Thermal treatment could effectively remove the surface adsorbed water and impurities and improved the catalytic activity. The addition of ZnO to CaO significantly enhanced the catalysts' stability; however, it led to lower surface basicity and slightly diminished catalytic activity. ZnO doping inhibited the formation of surface Ca(OH)2 and promoted the formation of Ca–Zn–O or CaZn2(OH)6 phase as the core and a surface CaCO3 shell, which effectively decreased Ca2+ leaching by approximately 74% in methanol and 65% in a methanol–glycerol (4:1) mixture. A combined method of separation and purification for obtaining clean biodiesel with high quality was proposed. The biodiesel obtained under the control conditions exhibited properties which satisfied the corresponding standards well. [ABSTRACT FROM AUTHOR]

Short strong hydrogen bonds (SSHBs) play a crucial role in many chemical processes. Recently, as the representative of SSHBs, [F–H–F]− was experimentally observed. [F–H–F]− has a symmetric structure, which can be described as a H+ acid shared by two terminal F− donors (F−–H+–F−). To explore whether two identical donors are bound to result in SSHBs, we performed theoretical studies on a series of compounds (L–H+–L) with two identical electron donors (L corresponds to donors containing group 14, 15, 16, and 17 elements). The results show that identical donors do not definitely lead to SSHBs. Instead, typical hydrogen bonds also exist. Both electronegativity and basicity contribute to the patterns of hydrogen bonds, where more electronegative and weaker donors benefit to SSHBs. In addition, it was found that zero-point energies also respond to the hydrogen bonding systems. This systemic work is expected to provide more insights into SSHBs. [ABSTRACT FROM AUTHOR]

Calcium ion batteries (CIBs) are considered as an important candidate for post‐lithium energy storage devices due to their abundance of resources and low cost. However, CIBs still suffer from slow kinetics due to the large solvation structure and high desolvation energy of Ca2+ ions. Here, a solvation regulation strategy based on donor number (DN) is reported to achieve easy‐desolvation and rapid storage of Ca2+ in sodium vanadate (Na2V6O16·2H2O, NVO). Specially, the solvent with a low DN, represented by propylene carbonate (PC), forms the first solvation shell of calcium ions with weak binding energy and small shell structure, which facilitates the migration of Ca2+ in the electrolyte. More importantly, the low DN solvent is preferentially desolvated at the cathode/electrolyte interface, promoting the insertion of Ca2+ into the NVO electrode. Mechanism studies further confirm the highly reversible uptake/release of Ca2+ in the NVO cathode, along with the VO distance change in the coordination structure. Therefore, the NVO cathode achieves high capacity (376 mAh g−1 at 0.3 A g−1) and high‐rate performance (151 mAh g−1 at 5 A g−1). The weak solvation effect strategy further improves the electrochemical performance and provides great importance for the design of the long‐term development of CIBs. [ABSTRACT FROM AUTHOR]

A cross-linkable solubilizer with a high Gutmann donor number is applied to facilitate the dissolution of insoluble LiNO 3 in carbonate-based electrolytes, and to form gel polymer electrolytes through in situ polymerization process. The Li+ solvation structure of GPEs is regulated by LiNO 3 and DMAA, which suppresses the decomposition of LiPF 6 and promotes the formation of an inorganic-rich SEI. [Display omitted] High-voltage lithium metal batteries (LMBs) have been considered promising next-generation high-energy–density batteries. However, commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor compatibility with metallic lithium. N , N -dimethylacrylamide (DMAA)—a crosslinkable solubilizer with a high Gutmann donor number—is employed to facilitate the dissolution of insoluble lithium nitrate (LiNO 3) in carbonate-based electrolytes and to form gel polymer electrolytes (GPEs) through in situ polymerization. The Li+ solvation structure of the GPEs is regulated using LiNO 3 and DMAA, which suppresses the decomposition of LiPF 6 and facilitates the formation of an inorganic-rich solid electrolyte interface. Consequently, the Coulombic efficiency (CE) of the Li||Cu cell assembled with a GPE increases to 98.5% at room temperature, and the high-voltage Li||NCM622 cell achieves a capacity retention of 80.1% with a high CE of 99.5% after 400 cycles. The bifunctional polymer electrolytes are anticipated to pave the way for next-generation high-voltage LMBs. [ABSTRACT FROM AUTHOR]