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Shotcrete mortar is an imperative material for tunnel surface supporting. The mine environment with different temperature affects the mechanical development of mortar, resulting in a difficult to predict its compressive strength development at high temperature. In this investigation, the compressive strength, hydration heat, mineral evolution, pore content of mortar samples at 20 and 60 °C, containing partial steel slag powder, were comprehensively compared by experiment and simulation in order to provide a reliable approach for underground materials compressive strength prediction. Results show that the compressive strength development of the samples cured at 20 and 60 °C, is consisted with the corresponding cumulative hydration heat, and the correlation coefficient is higher than 0.96. The hydrates and heat of the samples are significantly affected by the cement type, mineral admixture, and temperature. Indeed, increasing temperature significantly accelerates the minerals’ hydration and heat release. Combining the composition, pore and single mineral hydration heat simulation, the mortar compressive strength development of the mortar in deep mine can be predicted by a thermodynamic model.

The electrochemical behavior of electrodeposited Al–Mg alloy coating was studied via cyclic voltammetry (CV), chronoamperometry and chronopotentiometric techniques in C4H8O–C6H6–LiAlH4–AlCl3–MgX2(X = Cl, Br) electrolyte, and the electrodeposites were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The result showed that co–deposition of Al and Mg started at −0.45 V (vs Al) attributing to the electrochemical reduction from electrochemically Mg(AlH4)2in C4H8O–C6H6–LiAlH4–AlCl3–MgCl2. However, co–deposition of Al and Mg started at −0.48 and −0.82 V in C4H8O–C6H6–LiAlH4–AlCl3–MgBr2, contributing from two different types of electrochemically active products, including of Mg(AlH4)2and MgAl2Cl8. Moreover, it was suggested the electrochemical behavior of the electrochemically active materials was related not only to the applied potential, but also to the concentration of MgBr2in the electrolyte. The CV curves showed that the electrochemical process of electrodeposited Al–Mg was not completely reversible. Moreover, it was suggested that the electrodeposition process was controlled by diffusion, and the nucleation process is identified as instantaneous nucleation. The maximum magnesium content of 13.3% can be acquired when the current density of 17.8 mA/cm2was applied. The optimum process conditions of current density (15–21 mA/cm2) and electrodeposition time (1–1.5 h) were suggested for electrodeposition of Al–Mg alloy.

Coal gangue and slime water are difficult to dispose and utilize on a large scale, which could cause environmental pollution and waste of resources. Therefore, the co-treatment of coal gangue and slime water can serve as an environmentally friendly and novel way for the collaborative resource of solid wastes. Based on this, a method for preparation of slime water-based cementitious material (SWCM) was developed, and the enhanced mechanical property of a coal gangue pile modified by SWCM (CGSWCM) was investigated. For the preparation of SWCM, 6 types of additives were selected, and solidification was achieved with a liquid to solid ratio of 3:1. A compressive strength of 0.45 MPa was acquired with raw SWCM, and the value decreased to 0.38 MPa, then increased to 0.44 MPa when the mass of the kaolin increased from 2 to 10 g. X-ray diffraction and scanning electron microscopy results showed that the pore size of the coal gangue pile decreased and the rod-like ettringite transferred to a linear shape when mass of kaolin increased. The analysis of thermogravimetry proved that the increased mass of kaolin improved the thermal stability, thus decreasing the mass loss. Therefore, it was proposed that the mechanical properties of CGSWCM was affected by evolved hydration product, gap between coal gangue particles and ettringite (AFT) morphology.

NiO and Ni powders were prepared using plasma discharge electrolysis from NiSO4 solution and NiSO4-NiCl2 solution, respectively. Combining the effects of the electrolysis parameters, thermodynamic calculations, emission spectra, and product characterization, the mechanism of the formation process was analyzed. As a result, pure NiO was be obtained from a 0.4 M NiSO4 solution at 150 V and 10 min, and Ni powder was produced from a solution of 0.15 M NiSO4-0.05 M NiCl2 with the operating electrode immersed 1 mm into the electrolyte. The formation of NiO was attributed to the oxidation of Ni formed in the reaction via Ni + H2O - NiO + H2; pure Ni was generated via reduction by electrons and H radicals formed under these mild experimental conditions, which can avoid further oxidization to NiO. Furthermore, the temperature at the discharge area was estimated to be >1300 K, and the temperature at the thin layer beneath the discharge area, where NiO was produced, was between 771 and 1300 K. However, the temperature at the thin layer around the discharge area was <771 K during the preparation of Ni. Therefore, the mechanism for the formation of NiO and Ni was proposed according to the deviation in temperature. Multi-electrode electrolysis was used for the preparation of NiO and Ni, and the particle size distribution of NiO and Ni was 0.26-24.5 um and 0.1-24.67 um, respectively.

Herein, inspired by previous reports on the electrochemical reduction of Al in diverse electrolyte systems, we describe a novel Al-containing solvate ionic liquid (2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl3) that allows low-temperature electrochemical deposition of Al and features the advantages of low cost, ease of preparation, and high electrochemical stability. Electrodeposition of Al-Li alloy and Li can also be realized in this system. Additionally, the above ionic liquid exhibited a saturated vapor pressure of 0.0012 kPa and a conductivity of 1.32 mS/cm at 298 K, which was acceptable for practical applications. To elucidate the electrochemical deposition mechanism, the ionic components of the 2:1 EC/AlCl3 system were characterized by a range of instrumental analysis techniques and theoretical calculations, and Lewis-acidic cations were identified as the electroactive species for Al electrodeposition. Notably, an Al-Li alloy could be obtained by co-deposition in the new solvate ionic liquid, and Li metal could also be electrodeposited on a high-purity Al plate in the form of Al4Li9 and Li3Al2 under ambient conditions using LiCl as a Li source. Al-containing solvate ionic liquids, which to an extent evolved from organic-salts, are of increasing interest. They are expected to gain more attention in the field of electrochemical metallurgy of active metals, due to their higher tunability and lower price.

Fine Cu powder was prepared by a solid[?]liquid plasma discharge electrolysis process using a CuSO4 - H2SO4 solution. The X-ray diffraction results indicated the presence of Cu2O impurity in the obtained Cu powder. The Cu content in the powder increased with increase in the concentration of CuSO4, and pure ultra-fine Cu powder was obtained using 0.2 M CuSO4 - 0.2 M H2SO4 solution. Emission spectrum analyses indicated that a large number of hydrogen radicals (H[?]) generated in solution contained H2SO4 during the process of plasma discharge was the reason for the formation of pure Cu, therefore the formation mechanism of Cu could be described by the whole reaction Cu2+ + 2H[?] - Cu + 2H+, and the formation of impurity Cu2O was caused by the reaction of Cu2(OH)22++ 2e[?] - Cu2O + H2O in electrolyte. The formation process of Cu and Cu2O in two types of solution were described in detail. Scanning electron microscopy analyses indicated that Cu2O particles were polyhedron-shaped with an average diameter of 100-200 nm.

This study analyzes the visibility characteristics in Beijing from 2015 to 2020 using the 10-min average horizonal visibility hourly data from 20 national meteorological stations (NMSs). We examine the visibility trends on different time and space scales, including year, month, day. Our findings reveal that the visibility of the Beijing area shows a noticeable change trend year by year. Overall, the number of days with high visibility (visibility ≥10 ​km) has increased, and the number of hours with low visibility (visibility < 1 ​km) has decreased. Low visibility in Beijing mainly occurs during winter, whereas high visibility occurs throughout the year. On a daily scale, low visibility mainly occurs around 6 a.m. and 8 p.m. Furthermore, the spatial distribution of high and low visibility in Beijing correlates with the topographic boundary between plains and mountains. We observed that mountainous areas have more days with increased visibility and fewer hours with low visibility, while plain areas have fewer days with high visibility and more hours with high visibility. These findings have implications for understanding the environmental hazards caused by poor visibility in Beijing, such as impaired air quality, increased traffic accidents, and reduced human mobility. By identifying the temporal and spatial patterns of visibility, this study provides valuable information that can be used to improve hazard mitigation strategies and promote public safety.

WDR5 is a critical chromatin cofactor of MYC. WDR5 interacts with MYC through the WBM pocket and is hypothesized to anchor MYC to chromatin through its WIN site. Blocking the interaction of WDR5 and MYC impairs the recruitment of MYC to its target genes and disrupts the oncogenic function of MYC in cancer development, thus providing a promising strategy for the treatment of MYC-dysregulated cancers. Here, we describe the discovery of novel WDR5 WBM pocket antagonists containing a 1-phenyl dihydropyridazinone 3-carboxamide core that was identified from high-throughput screening and subsequent structure-based design. The leading compounds showed sub-micromolar inhibition in the biochemical assay. Among them, compound 12can disrupt WDR5–MYC interaction in cells and reduce MYC target gene expression. Our work provides useful probes to study WDR5–MYC interaction and its function in cancers, which can also be used as the starting point for further optimization toward drug-like small molecules.

Drug resistance is a major problem often limiting the long-term effectiveness of targeted cancer therapeutics. Resistance can be acquired through mutations or amplification of the primary drug targets or activation of bypass signaling pathways. Considering the multifaceted function of WDR5 in human malignancies, WDR5 has emerged as an attractive drug target for the discovery of small-molecule inhibitors. In this study, we investigated if cancer cells might develop resistance to a highly potent WDR5 inhibitor. We established a drug-adapted cancer cell line and discovered that WDR5P173Lmutation occurs in the resistant cells, which confers resistance by preventing target engagement of the inhibitor. This work elucidated the WDR5 inhibitor’s potential resistance mechanism in a preclinical study as a reference for future study in the clinical stage.

The interaction mechanism between coal and rock masses with supporting materials is significant in roadway control, especially in deep underground mining situations where dynamic hazards frequently happened due to high geo-stress and strong disturbed effects. This paper is to investigate the strain energy evolution in the interaction between coal and rock masses with self-designed energy-absorbing props and rock bolts by numerical modeling with the finite difference method. The interaction between rock and rock bolt/prop is accomplished by the cables element and the interface between the inner and outer prop. Roadway excavation and coal extraction conditions in deep mining are numerically employed to investigate deformation, plastic zone ranges, strain energy input, accumulation, dissipation, and release. The effect on strain energy input, accumulation, dissipation, and release with rock deformation, and the plastic zone is addressed. A ratio of strain energy accumulation, dissipation, and release with energy input α, β, γis to assess the dynamic hazards. The effects on roadway excavation and coal extraction steps of α, β, γare discussed. The results show that: (1) In deep high geo-stress roadways, the energy-absorbing support system plays a dual role in resisting deformation and reducing the scope of plastic zones in surrounding rock, as well as absorbing energy release in the surrounding rock, especially in the coal extraction state to mitigate disturbed effects. (2) The strain energy input, accumulation is dependent on roadway deformation, the strain energy dissipation is relied on plastic zone area and disturbed effects, and strain energy release density are the difference among the three. The function of energy-absorbing rock bolts and props play a key role to mitigate strain energy release density and amount, especially in coal extraction condition, with a peak density value from 4×104to 1×104J/m3, and amount value from 3.57×108to 1.90×106J. (3) When mining is advanced in small steps, the strain energy accumulation is dominated. While in a large step, the released energy is dominant, thus a more dynamic hazards proneness. The energy-absorbing rock bolt and prop can reduce three times strain energy release amount, thus reducing the dynamic hazards. The results suggest that energy-absorbing props and rock bolts can effectively reduce the strain energy in the coal and rock masses, and prevent rock bursts and other hazards. The numerical model developed in this study can also be used to optimize the design of energy-absorbing props and rock bolts for specific mining conditions.

WD repeat domain 5 (WDR5) is a member of the WD40-repeat protein family that plays a critical role in multiple processes. It is also a prominent target for pharmacological inhibition in diseases such as cancer, aging, and neurodegenerative disorders. Interactions between WDR5 and various partners are essential for sustaining its function. Most drug discovery efforts center on the WIN (WDR5 interaction motif) site of WDR5 that is responsible for the recruitment of WDR5 to chromatin. Here, we describe the discovery of novel WDR5 inhibitors for the other WBM (WDR5 binding motif) pocket on this scaffold protein, to disrupt WDR5 interaction with its binding partner MYC by high-throughput biochemical screening, subsequent molecule optimization, and biological assessment. These new WDR5 inhibitors provide useful probes for future investigations of WDR5 and an avenue for targeting WDR5 as a therapeutic strategy.

3D pharmacophore modeling is an important computational methodology for ligand-enzyme binding interactions in drug discovery. More specifically, a consensus pharmacophore model derived from diverse ligands is a key determinant upon which the prediction power of computational models is based for designing novel ligands. In this work, by merging the important pharmacophore features based on four classes of covalent FAAH ligands, and then integrating the exclusion volume spheres derived from the crystal structure, we created for the first time an integrated FAAH pharmacophore model to describe the ligand-enzyme binding interactions. This new integrated FAAH pharmacophore model can correctly predict the covalent ligand binding mode, which correlates with the SAR data. The study is expected to provide insights into novel covalent ligand-FAAH binding interactions, and facilitate the design of covalent ligands against FAAH.

Highly pure silicon is an important component in photovoltaic applications and has potential in battery technology. In this study, the electrochemical behavior of Si (IV) was discussed in a NaF−LiF−Na2SiO3−SiO2electrolyte at 750 °C, and lithium-ion battery performance with electrodeposited silicon powder as anode material were investigated. The cyclic voltammograms illustrated that the reduction of Si(IV) on an Ag electrode followed an irreversible two-step, two-electron process: Si(IV) → Si(II) and Si(II) → Si(0). Both reduction steps involved diffusion control, and the diffusion coefficients were 1.18 and 1.22 × 10−6cm2s−1, respectively. Nanoscale spherical silicon was deposited between potentials of −1.0 to −1.6 V (vs Pt) with support of X-ray diffraction patterns, Raman spectra, and scanning electron microscopy analysis. Combining the fabricated silicon with carbon, a Si@C composite anode material for lithium-ion batteries was prepared, and its specific capacity reached 1260 mA·h g−1. Notably, a capacity of 200 mA·h g−1was maintained over 100 cycles.

HIV-1 reverse transcriptase (RT) is the primary target for anti-AIDS chemotherapy. Nonnucleoside RT inhibitors (NNRTIs) are very potent and most promising anti-AIDS drugs that specifically inhibit HIV-1 RT. The binding and unbinding processes of α-APA, an NNRTI, have been studied using nanosecond conventional molecular dynamics and steered molecular dynamics simulations. The simulation results show that the unbinding process of α-APA consists of three phases based on the position of α-APA in relation to the entrance of the binding pocket. When α-APA is bound in the binding pocket, the hydrophobic interactions between HIV-1 RT and α-APA dominate the binding; however, the hydrophilic interactions (both direct and water-bridged hydrogen bonds) also contribute to the stabilizing forces. Whereas Tyr-181 makes significant hydrophobic interactions with α-APA, Tyr-188 forms a strong hydrogen bond with the acylamino group (N14) of α-APA. These two residues have very flexible side chains and appear to act as two “flexible clamps” discouraging α-APA to dissociate from the binding pocket. At the pocket entrance, two relatively inflexible residues, Val-179 and Leu-100, gauge the openness of the entrance and form the bottleneck of the inhibitor-unbinding pathway. Two special water molecules at the pocket entrance appear to play important roles in inhibitor recognition of binding and unbinding. These water molecules form water bridges between the polar groups of the inhibitor and the residues around the entrance, and between the polar groups of the inhibitor themselves. The water-bridged interactions not only induce the inhibitor to adopt an energetically favorable conformation so the inhibitor can pass through the pocket entrance, but also stabilize the binding of the inhibitor in the pocket to prevent the inhibitor’s dissociation. The complementary steered molecular dynamics and conventional molecular dynamics simulation results strongly support the hypothesis that NNRTIs inhibit HIV-1 RT polymerization activity by enlarging the DNA-binding cleft and restricting the flexibility and mobility of the p66 thumb subdomain that are believed to be essential during DNA translocation and polymerization.

Insights into the interacting mode of CXCR4 with SDF-1α are crucial in understanding the structural and functional characteristics of CXCR4 receptor. In this paper a computational pipeline, integrating protein structure prediction, molecular dynamics simulations, automated molecular docking, and Brownian dynamics simulations were employed to investigate the dynamic and energetic aspects of CXCR4 associating with SDF-1α. The entire simulation revealed the surface distribution feature of electrostatic potentials and conformational “open-close” process of the receptor. The possible binding conformation of CXCR4 was identified, and the CXCR4—SDF-1α binding complex was generated. Arg188-Glu277 salt bridge plays an important role for both the extracellular domain conformational change and SDF-1α binding. Two binding sites were mapped at the extracellular domain (Site 1) and inside the transmembrane domain (Site 2), which are composed of conserved residues. Sites 1 and 2 contribute ∼60% and 40% to the binding affinity with SDF-1α, respectively. The binding model is in agreement with most of the experimental data. Transmembrane VI has more significant motion in the harmonious conformational transition of CXCR4 during SDF-1α binding, which may be possibly associated with signal transduction. Based on the modeling and simulation, a binding mechanism hypothesis between CXCR4 and SDF-1α and its relationship to the signal transduction has been proposed.

NiO and Ni powders were prepared using plasma discharge electrolysis from NiSO4solution and NiSO4–NiCl2 solution, respectively. Combining the effects of the electrolysis parameters, thermodynamic calculations, emission spectra, and product characterization, the mechanism of the formation process was analyzed. As a result, pure NiO was be obtained from a 0.4 M NiSO4solution at 150 V and 10 min, and Ni powder was produced from a solution of 0.15 M NiSO4–0.05 M NiCl2with the operating electrode immersed 1 mm into the electrolyte. The formation of NiO was attributed to the oxidation of Ni formed in the reaction via Ni + H2O → NiO + H2; pure Ni was generated via reduction by electrons and H radicals formed under these mild experimental conditions, which can avoid further oxidization to NiO. Furthermore, the temperature at the discharge area was estimated to be >1300 K, and the temperature at the thin layer beneath the discharge area, where NiO was produced, was between 771 and 1300 K. However, the temperature at the thin layer around the discharge area was <771 K during the preparation of Ni. Therefore, the mechanism for the formation of NiO and Ni was proposed according to the deviation in temperature. Multi-electrode electrolysis was used for the preparation of NiO and Ni, and the particle size distribution of NiO and Ni was 0.26–24.5 μm and 0.1–24.67 μm, respectively.

Herein, inspired by previous reports on the electrochemical reduction of Al in diverse electrolyte systems, we describe a novel Al-containing solvate ionic liquid (2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl3) that allows low-temperature electrochemical deposition of Al and features the advantages of low cost, ease of preparation, and high electrochemical stability. Electrodeposition of Al-Li alloy and Li can also be realized in this system. Additionally, the above ionic liquid exhibited a saturated vapor pressure of 0.0012 kPa and a conductivity of 1.32 mS/cm at 298 K, which was acceptable for practical applications. To elucidate the electrochemical deposition mechanism, the ionic components of the 2:1 EC/AlCl3system were characterized by a range of instrumental analysis techniques and theoretical calculations, and Lewis-acidic cations were identified as the electroactive species for Al electrodeposition. Notably, an Al-Li alloy could be obtained by co-deposition in the new solvate ionic liquid, and Li metal could also be electrodeposited on a high-purity Al plate in the form of Al4Li9and Li3Al2under ambient conditions using LiCl as a Li source. Al-containing solvate ionic liquids, which to an extent evolved from organic-salts, are of increasing interest. They are expected to gain more attention in the field of electrochemical metallurgy of active metals, due to their higher tunability and lower price.

Fine Cu powder was prepared by a solid−liquid plasma discharge electrolysis process using a CuSO4- H2SO4solution. The X-ray diffraction results indicated the presence of Cu2O impurity in the obtained Cu powder. The Cu content in the powder increased with increase in the concentration of CuSO4, and pure ultra-fine Cu powder was obtained using 0.2 M CuSO4- 0.2 M H2SO4solution. Emission spectrum analyses indicated that a large number of hydrogen radicals (H⋅) generated in solution contained H2SO4during the process of plasma discharge was the reason for the formation of pure Cu, therefore the formation mechanism of Cu could be described by the whole reaction Cu2++ 2H⋅ → Cu + 2H+, and the formation of impurity Cu2O was caused by the reaction of Cu2(OH)22++ 2e−→ Cu2O + H2O in electrolyte. The formation process of Cu and Cu2O in two types of solution were described in detail. Scanning electron microscopy analyses indicated that Cu2O particles were polyhedron-shaped with an average diameter of 100–200 nm.

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