Effects of Na/K–Cl Salts on Hydrolysis of Aluminosilicate Glass Using Ab Initio Molecular Dynamics

The structural and chemical modifications on the surface of pure and alkali-doped aluminosilicate (AS) glasses due to hydrolysis are investigated using ab initio molecular dynamics. The effects of water on the glass network are fully elucidated by analyzing the short- and intermediate-range structural orders embedded in the pair distribution function, bond length and angle distribution, coordination number, and interatomic bonding. A novel concept of total bond order is used to quantify and compare the strength of bonds in hydrated and unhydrated glasses. We show that AS glass is hydrolyzed by water diffusion near the surface and by proton (H+) transfers into the bulk, which increases with time. Hence, a dissolved glass–water interface becomes rich in Si–OH and Al–OH. The alkali ions associated with the nonbridging oxygen accelerate the hydrolysis by facilitating water and H+ diffusion. Al is more impacted by hydrolysis than Si, resulting in greater variation in the Al–O bond order than Si–O. Doping of NaCl and KCl enhances the ionization of water and the hydrolysis of ASs with increased salt concentration. The KCl doping ionizes more water molecules and causes more degradation of the glass network than NaCl. Co-doping of Na and K results in a mixed alkali effect due to complex interatomic bonding from different-sized ions. These exceptionally detailed findings in highly complex glasses with varying salt compositions provide new and unprecedented atomistic insights that can help to understand the hydrolysis and dissolution mechanisms of ASs and other silicate glasses

Investigation on the synergy mechanism of mixed inhibitors – Mannich base and Na₂WO₄ on Fe surface by molecules dynamic simulation

Previous experimental results shows mixed Mannich base (C15H15NO) and Na2WO4 have demonstrated excellent corrosion prevention, and the best corrosion inhibition efficiency is 96.19% when the mixing ratio of the two components is 1:1. In order to clearly understand to inhibition mechanism, molecular dynamics were used to model the inhibition effects of C15H15NO or Na2WO4 molecule on the iron surface. The simulation results indicate there are synergistic effect between C15H15NO and Na2WO4. the synergistic effect has three main factors: for one, the synergistic effect is due to the WO42− (small) can fill in the voids of the C15H15NO (big), the mixed inhibitor film is denser than single inhibitor film; moreover, the WO42− forms H-bond group with H3O+, which makes corrosive particles harder to pass through adsorption film, simultaneously; In addition, the mixed inhibitor significantly reduces the free charges and ions on Fe surface, which makes metal structure is more stable.</p

Table_1_Integration Analysis of m6A-SNPs and eQTLs Associated With Sepsis Reveals Platelet Degranulation and Staphylococcus aureus Infection are Mediated by m6A mRNA Methylation.xlsx

Sepsis is a major threat with high mortality rate for critically ill patients. Response to pathogen infection by the host immune system is a key biological process involved in the onset and development of sepsis. Heterogeneous host genome variation, especially single nucleotide polymorphisms (SNPs), has long been suggested to contribute to differences in disease progression. However, the function of SNPs located in non-coding regions remains to be elucidated. Recently, m6A mRNA modification levels were revealed to differ at SNPs. As m6A is a crucial regulator of gene expression, these SNPs might control genes by changing the m6A level on mRNA. To investigate the potential role of m6A SNPs in sepsis, we integrated m6A-SNP and expression quantitative trait loci (eQTLs) data. Analysis revealed 15,720 m6A-cis-eQTLs and 381 m6A-trans-eQTLs associated with sepsis. We identified 1321 genes as locations of m6A-cis-eQTLs. These were enriched in platelet degranulation and Staphylococcus aureus infection pathways, which are vital for the pathophysiological process of sepsis. We conclude that m6A modification of mRNA plays a very important role in sepsis, with m6A-cis-eQTLs potentially having the most effect on individual variation in sepsis progression.</p

Table_3_Integration Analysis of m6A-SNPs and eQTLs Associated With Sepsis Reveals Platelet Degranulation and Staphylococcus aureus Infection are Mediated by m6A mRNA Methylation.xlsx

Sepsis is a major threat with high mortality rate for critically ill patients. Response to pathogen infection by the host immune system is a key biological process involved in the onset and development of sepsis. Heterogeneous host genome variation, especially single nucleotide polymorphisms (SNPs), has long been suggested to contribute to differences in disease progression. However, the function of SNPs located in non-coding regions remains to be elucidated. Recently, m6A mRNA modification levels were revealed to differ at SNPs. As m6A is a crucial regulator of gene expression, these SNPs might control genes by changing the m6A level on mRNA. To investigate the potential role of m6A SNPs in sepsis, we integrated m6A-SNP and expression quantitative trait loci (eQTLs) data. Analysis revealed 15,720 m6A-cis-eQTLs and 381 m6A-trans-eQTLs associated with sepsis. We identified 1321 genes as locations of m6A-cis-eQTLs. These were enriched in platelet degranulation and Staphylococcus aureus infection pathways, which are vital for the pathophysiological process of sepsis. We conclude that m6A modification of mRNA plays a very important role in sepsis, with m6A-cis-eQTLs potentially having the most effect on individual variation in sepsis progression.</p

Table_2_Integration Analysis of m6A-SNPs and eQTLs Associated With Sepsis Reveals Platelet Degranulation and Staphylococcus aureus Infection are Mediated by m6A mRNA Methylation.xlsx

Sepsis is a major threat with high mortality rate for critically ill patients. Response to pathogen infection by the host immune system is a key biological process involved in the onset and development of sepsis. Heterogeneous host genome variation, especially single nucleotide polymorphisms (SNPs), has long been suggested to contribute to differences in disease progression. However, the function of SNPs located in non-coding regions remains to be elucidated. Recently, m6A mRNA modification levels were revealed to differ at SNPs. As m6A is a crucial regulator of gene expression, these SNPs might control genes by changing the m6A level on mRNA. To investigate the potential role of m6A SNPs in sepsis, we integrated m6A-SNP and expression quantitative trait loci (eQTLs) data. Analysis revealed 15,720 m6A-cis-eQTLs and 381 m6A-trans-eQTLs associated with sepsis. We identified 1321 genes as locations of m6A-cis-eQTLs. These were enriched in platelet degranulation and Staphylococcus aureus infection pathways, which are vital for the pathophysiological process of sepsis. We conclude that m6A modification of mRNA plays a very important role in sepsis, with m6A-cis-eQTLs potentially having the most effect on individual variation in sepsis progression.</p

Highly NH₃ Sensitive and Selective Ti₃C₂O₂‑Based Gas Sensors: A Density Functional Theory-NEGF Study

Ammonia (NH3) detection at the early stage is an important precaution for human health and agricultural production. However, conventional sensing materials are difficult to achieve all the targeted operational performances such as low power consumption and high selectivity. MXenes are a type of graphene-like emergent material equipped with abundant surface sites benefiting gas-sensing applications. In the work, we discuss the sensing performance of Ti3C2O2 to anticipate harmful and polluting NH3 gases by density functional theory and nonequilibrium Green’s function. The adsorption geometry, charge difference density, and partial density of states are discussed to understand the nature of interactions between gas molecules and Ti3C2O2. The theoretical results show that only NH3 adsorbs onto the nanosheet through chemisorption. Then, a two-electrode Ti3C2O2-based gas sensor device is built to unravel the transport properties. Current under different bias voltages indicates the Ti3C2O2-based sensor could maintain extremely high sensitivity, demonstrating that Ti3C2O2 has great potential for the NH3 sensor with high selectivity, excellent sensitivity, and low energy consumption. Upon external electric fields, the adsorption energy and charge transfer can be tuned effectively, suggesting that Ti3C2O2 is a versatile agent as an ammonia-sensing material

Role of Sodium Ion on TiO₂ Photocatalyst: Influencing Crystallographic Properties or Serving as the Recombination Center of Charge Carriers?

There have been continuing debates about the role of Na⁺ on TiO₂ photocatalyst in the past decades. Most researchers accepted that Na⁺ served as the recombination center of photogenerated electrons and holes. Nevertheless, other opinions also existed, such as Na⁺ increased the crystallite size of TiO₂, Na⁺ hampered the crystallization of anatase TiO₂, and Na⁺ promoted the formation of brookite TiO₂ or titanate sodium. In this research, we have systematically investigated the role of Na⁺ during the fabrication of TiO₂ film and powder through the sol–gel method and studied the influences of crystallinity and the content of Na⁺ on the photocatalytic activities of TiO₂ film and powder. It has been found that the existence of Na⁺ in TiO₂ film and powder should influence their crystallographic properties, in detail, inhibiting the crystallization and growth of anatase phase in TiO₂ film and powder, promoting the formation of brookite phase in TiO₂ film, and increasing the transformation temperature of anatase to rutile phase in TiO₂ powder. Even though the existence of Na⁺ forms the Ti–O–Na bond on the surface of TiO₂, however, the widely adopted hypothesis of Na⁺ serving as the recombination center of photogenerated electrons and holes is not correct

Structure and Electronic Properties of a Continuous Random Network Model of an Amorphous Zeolitic Imidazolate Framework (a-ZIF)

Zeolitic imidazolate frameworks (ZIFs) are a rapidly emerging class of versatile porous material with many potential applications. Here, we report the construction of an amorphous ZIF (a-ZIF) model from a near-perfect continuous random network model of a-SiO2. The radial distribution function is in good agreement with measurements for amorphous aTZIF-4 but with notable fine differences. The electronic structure and properties of the a-ZIF model are critically compared with those of three crystalline ZIF phases, ZIF-4, ZIF-zni, and ZIF-8, using density functional theory methods. We confirm the retention of the metal tetrahedral bonding coordination in a-ZIF and the nearly identical short-range ordering found in crystalline ZIFs. The considerable Zn–N bond strength plays a key role in retaining the tetrahedrally bonded network structure. The calculated optical properties of a-ZIF show a complex absorption spectrum with an ultralow refractive index n of 1.327 and a plasmon frequency of 15.810 eV

Single-Metal Atoms Supported on MBenes for Robust Electrochemical Hydrogen Evolution

Two-dimensional (2D) photo- and electrocatalysts play a key role in hydrogen production through water splitting, and much efforts have been undertaken to seek a low-cost and efficient alternative candidate to noble-metal Pt. Herein, the method of introducing several different transition-metal atoms to tune the catalytic properties of 2D MBene is proposed. Density functional theory calculations reveal that the H–O bonding strength can be weakened by charge transfer between the oxygen atom and the introduced single-metal atom. The weakening of the bond greatly improves the MBene catalytic activity of hydrogen evolution reaction. Interestingly, the Gibbs free energy (|ΔGH|) of W2B2O2 decreases from |−0.67| to 0.013 eV by embedding a V adatom. This work should initiate 2D material MBene applications in green catalysis and energy sectors

Facile Melting-Crystallization Synthesis of Cs₂Na_<i>x</i>Ag_1–<i>x</i>InCl₆: Bi Double Perovskites for White Light-Emitting Diodes

Lead-free double perovskites (DPs) have outstanding luminescent properties, which make them excellent candidates for wide use in optoelectronics. Herein, a solvent-free melting-crystallization technique, which can produce kilogram-scale DP microcrystals (DP-MCs) in one batch, is invented to synthesize the Cs2NaxAg1–xInCl6: Bi (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) DP-MCs. The structure and composition analysis confirmed the products are pure Cs2NaxAg1–xInCl6 DP-MCs. Affected by Jahn–Teller distortion of AgCl6 octahedra, self-trapped excitons appear in the excited state, resulting in the broadband emission (400–850 nm) of Cs2Ag1–xNaxInCl6: Bi DP-MCs. The enhancement of the photoluminescence quantum yield can be realized by introducing Na+ to break the parity-forbidden transition in the Cs2AgInCl6 DP. Optimized Cs2Na0.4Ag0.6InCl6: Bi DP-MC phosphors combined with commercial blue and green phosphors were coated on ultraviolet chips (365 nm) to fabricate white light-emitting diodes (WLEDs) from warm white (2930 K) to cold white (6957 K). An ultrahigh color rendering index of 97.1 and a CCT of 5548 K as well as Commission Internationale de l’Eclairage color coordinates of (0.331, 0.339) have been demonstrated. This kilogram-scale synthesis technique could stimulate the industrial development of WLEDs for general lighting based on DP-MC phosphors