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Organic-inorganic hybrid materials are a promising class of materials for tissue engineering and other biomedical applications. In this systematic study, the effect of the polymer molecular mass (MM) with a linear architecture on hybrid mechanical properties is reported. Well-defined linear poly(methyl methacrylate-co-(3-(trimethoxysilyl)propyl methacrylate)) polymers with a range of MMs of 9 to 90 kDa and one 90 kDa star-shaped polymer were synthesized and then used to form glass-polymer hybrids. It was demonstrated that increasing linear polymer MM decreases the resultant hybrid mechanical strength. Furthermore, a star-polymer hybrid was synthesized as a comparison and demonstrated significantly different mechanical properties relative to its linear-polymer counterpart.To solve the problem of poor dust wettability during coal mine dust treatment, sodium dodecyl sulfate (SDS) and alkyl glycoside (APG1214) were selected for compounding. An efficient, environmentally friendly, economical wetting agent was prepared. First, through molecular dynamics simulation studies, it was determined that the tail group C of SDS and APG1214 was adsorbed on the surface of bituminous coal, and the head groups S and O were adsorbed on the surface of water. The simulation result is found to be consistent with the surfactant solution dust removal theory, which proves the confidence of simulation. Then, by comparing the interaction of water-SDS and APG1214-bituminous coal and water-bituminous coal systems and the number of hydrogen bonds, the wetting mechanism of the SDS and APG1214 solution on bituminous coal was revealed. Finally, the surface tension, contact angle, and wetting time of different SDS and APG1214 solutions were determined by experiments and they decreased with decreasing mass fraction of SDS at the same concentration. The surface tension of the SDS and APG1214 solution and the number of micelles affected the wettability of bituminous coal. The optimal concentration of the SDS and APG1214 solution was 0.7%, and the optimal ratio was SDS/APG1214 = 13.This work examines the influences of amyloid fibers of hen egg white lysozyme (HEWL) on the formation of melanin-like species (MLS) with a rationally selected set of catechol derivatives. Catechol-amyloid interactions, which are central in melanogenesis, are complex and multifaceted, making them difficult to understand at the molecular level. The catechol derivatives are set to interact with HEWL amyloid fibers upon altering pH, and the resultant formation of MLS is characterized. For obtaining clues for the molecular mechanism by which HEWL fibers regulate the formation of MLS, putative intermolecular interactions are individually perturbed and their ramifications are analyzed. With the entire data set, we could conclude that the externally presented nucleophilic moieties of HEWL fibers play a major role in regulating the material and kinetic properties of MLS and their formation, respectively.This work presents a mechanistic study of the electrochemical synthesis of magnetite nanoparticles (NPs) based on the analysis of the electrochemical impedance spectroscopy (EIS) technique. After a discussion of the mechanisms reported in the literature, three models are devised and a prediction of their EIS spectra is presented. The approach consisted of the simulation of EIS spectra as a tool for assessing model validity, as EIS allows to characterize the relaxation of adsorbed intermediates. The comparison between the simulated impedance spectra and the experimental results shows that the mechanisms proposed to date do not explain all of the experimental results. Thus, a new model is proposed, in which up to three adsorbed intermediate species are involved. This model accounts for the number of loops found in experimental impedance data. The closest approximation of the features found in the experimental spectra by this proposed model suggests a better representation of the reaction mechanism within the evaluated potential range.The interaction between graphene-based materials and hydrogen isotopes is of great importance with respect to the adsorption of hydrogen in graphene and the removal of tritium from irradiated nuclear graphite. In the present study, based on density functional theory, we investigate and discuss the adsorption and molecular desorption of hydrogen isotopes on the edges and stable interior defects. The adsorption energy of one hydrogen on graphene-based materials is between -2.0 and -5.0 eV, which is related to the structure and hydrogenation level. The hydrogenation level increases with the hydrogen partial pressure and decreases with the temperature. The best adsorption pathways of hydrogen isotopes in graphene-based materials are determined, together with three different desorption stages with different activation energies. The desorption peaks of thermal desorption spectrometry agree well with stage 2 and stage 3 of simulation. Our results can provide a theoretical basis for the study of the hydrogen isotope behaviors in graphene and the decontamination of nuclear graphite.It is critical to modulate the Fermi level of graphene for the development of high-performance electronic and optoelectronic devices. Here, we have demonstrated the modulation of the Fermi level of chemical vapor deposition (CVD)-grown monolayer graphene (MLG) via doping with nanoparticles to macromolecules such as titanium dioxide nanoparticles (TiO2 NPs), nitric acid (HNO3), octadecyltrimethoxysilane (OTS) self-assembled monolayer (SAM), and poly(3,4-ethylene-dioxythiophene)polystyrene sulfonate (PEDOTPSS). The electronic properties of pristine and doped graphene samples were investigated by Raman spectroscopy and electrical transport measurements. The right shifting of G and 2D peaks and reduction in 2D to G peak intensity ratio (I 2D/I G) assured that the dopants induced a p-type doping effect. Upon doping, the shifting of the Dirac point towards positive voltage validates the increment of the hole concentration in graphene and thus downward shift of the Fermi level. More importantly, the combination of HNO3/TiO2 NP doping on graphene yields a substantially larger change in the Fermi level of MLG. Our study may be useful for the development of graphene-based high-performance flexible electronic devices.The poor sealing effect of gas extraction boreholes causes low efficiency of gas extraction. As a consequence, the requirements of coal mine safety production are often not attained. The sealing effect of boreholes depends not only on the sealing material itself but also on the combination degree between the material and the hole wall and the structural change characteristics of the material during operation. Our theoretical analysis shows that the amount of liquid leakage increases with the gap width Δh in a cubic law, decreases with the sealing hole viscosity in a hyperbolic form, increases linearly with the diameter of the borehole, and increases with the eccentricity in a quadratic function. We have developed a PD sealing material that has good compactness and sealing effects, excellent water retention performance, and an expansion rate of 1.29. The material can generate secondary expansion through microscopic development, which is beneficial to improve the quality of the sealing hole. HV-CMC has good stability in plugging mucus. [https://www.selleckchem.com/products/a939572.html A939572 cell line] In addition, the manual pump has been redeveloped to be portable and also to overcome the blockage of the suction valve of the original device. In addition, the auxiliary device for drilling and sealing has been invented. The field application demonstrates that the gas concentration and flow pressure difference of the new sealing borehole can be maintained at a high level in a short period of time and then decrease slowly with time. The resulting improved sealing effect demonstrates that our new approach has important theoretical and practical significance for mine gas drainage.The heterochromatin protein 1 (HP1) sub-family of CBX chromodomains are responsible for the recognition of histone H3 lysine 9 tri-methyl (H3K9me3)-marked nucleosomal substrates through binding of the N-terminal chromodomain. These HP1 proteins, namely, CBX1 (HP1β), CBX3 (HP1γ), and CBX5 (HP1α), are commonly associated with regions of pericentric heterochromatin, but recent literature studies suggest that regulation by these proteins is likely more dynamic and includes other loci. Importantly, there are no chemical tools toward HP1 chromodomains to spatiotemporally explore the effects of HP1-mediated processes, underscoring the need for novel HP1 chemical probes. Here, we report the discovery of HP1 targeting peptidomimetic compounds, UNC7047 and UNC7560, and a biotinylated derivative tool compound, UNC7565. These compounds represent an important milestone, as they possess nanomolar affinity for the CBX5 chromodomain by isothermal titration calorimetry (ITC) and bind HP1-containing complexes in cell lysates. These chemical tools provide a starting point for further optimization and the study of CBX5-mediated processes.This research reports the synthesis of new benzimidazole-derived N-acylhydrazones (NAH), their characterization using various spectroscopic methods, and in vitro evaluation as potent carbonic anhydrase-II inhibitors. Among the target compounds (9-29), few showed higher inhibition than the standard acetazolamide (IC50 18.6 ± 0.43 μM), for example, compound 9 (IC50 13.3 ± 1.25 μM), 10 (IC50 17.2 ± 1.24 μM), 12 (IC50 14.6 ± 0.62 μM), and 15 (IC50 14.5 ± 1.05 μM). Molecular docking was performed on the most active compounds, which revealed their binding interactions with the active site of the enzyme, thus supporting the experimental findings.Despite its remarkable properties, phosphorene is not promising for device application due to its instability or gradual degradation under ambient conditions. The issue still persists, and no technological solution is available to address this degradation due to a lack of clarity about degradation dynamics at the atomic level. Here, we discuss atomic level degradation dynamics of phosphorene under ambient conditions while investigating the involvement of degrading agents like oxygen and water using density functional theory and first-principles molecular dynamics computations. The study reveals that the oxygen molecule dissociates spontaneously over pristine phosphorene in an ambient environment, resulting in an exothermic reaction, which is boosted further by increasing the partial pressure and temperature. The surface reaction is mainly due to the lone pair electrons of phosphorous atoms, making the degradation directional and spontaneous under oxygen atoms. We also found that while the pristine phosphorene is hydrophobic, it becomes hydrophilic after surface oxidation. Furthermore, water molecules play a vital role in the degradation process by changing the reaction dynamics path of the phosphorene-oxygen interaction and reducing the activation energy and reaction energy due to its catalyzing action. In addition, our study reveals the role of phosphorous vacancies in the degradation, which we found to act as an epicenter for the observed oxidation. The oxygen attacks directly over the vacant site and reacts faster compared to its pristine counterpart. As a result, phosphorene edges resembling extended vacancy are prominent reaction sites that oxidize anisotropically due to different bond angle strains. Our study clears the ambiguities in the kinetics of phosphorene degradation, which will help engineer passivation techniques to make phosphorene devices stable in the ambient environment.