Mechanism Of Modification Research Articles

N6-methyladenosine-modified SRPK1 promotes aerobic glycolysis of lung adenocarcinoma via PKM splicing

BackgroundThe RNA N6-methyladenosine (m6A) modification has become an essential hotspot in epigenetic modulation. Serine–arginine protein kinase 1 (SRPK1) is associated with the pathogenesis of various cancers. However, the m6A modification of SRPK1 and its association with the mechanism of in lung adenocarcinoma (LUAD) remains unclear.MethodsWestern blotting and polymerase chain reaction (PCR) analyses were carried out to identify gene and protein expression. m6A epitranscriptomic microarray was utilized to the assess m6A profile. Loss and gain-of-function assays were carried out elucidate the impact of METTL3 and SRPK1 on LUAD glycolysis and tumorigenesis. RNA immunoprecipitation (RIP), m6A RNA immunoprecipitation (MeRIP), and RNA stability tests were employed to elucidate the SRPK1’s METTL3-mediated m6A modification mechanism in LUAD. Metabolic quantification and co-immunoprecipitation assays were applied to investigate the molecular mechanism by which SRPK1 mediates LUAD metabolism.ResultsThe epitranscriptomic microarray assay revealed that SRPK1 could be hypermethylated and upregulated in LUAD. The main transmethylase METTL3 was upregulated and induced the aberrant high m6A levels of SRPK1. Mechanistically, SRPK1’s m6A sites were directly methylated by METTL3, which also stabilized SRPK1 in an IGF2BP2-dependent manner. Methylated SRPK1 subsequently promoted LUAD progression through enhancing glycolysis. Further metabolic quantification, co-immunoprecipitation and western blot assays revealed that SRPK1 interacts with hnRNPA1, an important modulator of PKM splicing, and thus facilitates glycolysis by upregulating PKM2 in LUAD. Nevertheless, METTL3 inhibitor STM2457 can reverse the above effects in vitro and in vivo by suppressing SRPK1 and glycolysis in LUAD.ConclusionIt was revealed that in LUAD, aberrantly expressed METTL3 upregulated SRPK1 levels via an m6A-IGF2BP2-dependent mechanism. METTL3-induced SRPK1 fostered LUAD cell proliferation by enhancing glycolysis, and the small-molecule inhibitor STM2457 of METTL3 could be an alternative novel therapeutic strategy for individuals with LUAD.

Hierarchical learning multi-objective firefly algorithm for high-dimensional feature selection

Feature selection is a crucial data preprocessing technique extensively employed in machine learning and image processing. However, feature selection encounters significant challenges when addressing high-dimensional data due to the huge and discrete decision space. This paper proposes a hierarchical learning multi-objective firefly algorithm (HMOFA) for solving the feature selection task in high-dimensional data. The main contributions are as follows: 1) Features are clustered based on the evaluation of multiple metrics, which are used to initialize the population and improve the quality of the initial population; 2) A hierarchy-guided learning model is proposed, where individuals move toward superior solutions while moving away from inferior solutions, avoiding the oscillation phenomenon that occurs under the full attraction model, and reducing the likelihood of the population being trapped in a local optimum; 3) Use duplicate solution modification mechanism to reduce the number of duplicate individuals in the population. The proposed method is compared with 8 competitive feature selection methods using 15 datasets, and the results demonstrate that HMOFA can achieve higher classification accuracy while selecting fewer features.

Remodeling of the bone marrow microenvironment during acute myeloid leukemia progression.

Hematopoiesis requires a complex interplay between the hematopoietic stem and progenitor cells and the cells of the bone marrow microenvironment (BMM). The BMM is heterogeneous, with different regions having distinct cellular, molecular, and metabolic composition and function. Studies have shown that this niche is disrupted in patients with acute myeloid leukemia (AML), which plays a crucial role in disease progression. This review provides a comprehensive overview of the components of vascular and endosteal niches and the molecular mechanisms by which they regulate normal hematopoiesis. We also discuss how these niches are modified in the context of AML, into a disease-promoting niche and how the modified niches in turn regulate AML blast survival and proliferation. We focus on mechanisms of modifications in structural and cellular components of the bone marrow (BM) niche by the AML cells and its impact on leukemic progression and patient outcome. Finally, we also discuss mechanisms by which the altered BM niche protects AML blasts from treatment agents, thereby causing therapy resistance in AML patients. We also summarize ongoing clinical trials that target various BM niche components in the treatment of AML patients. Hence, the BM niche represents a promising target to treat AML and promote normal hematopoiesis.

New insights into improved SO2＆H2O resistance over MoCrCeOx catalyst by CTAB for medium-low temperatures NH3-SCR: Regulation of surface acid and oxygen species

Selective catalytic reduction (NH3-SCR) of NH3 is the most efficient NOx removal technology. Improving the SO2/H2O resistance of SCR catalyst is of great importance for its industrial application. The Mo(0.3)-CrCeOx catalysts synthesized by the citric acid method exhibited excellent high concentration SO2 resistance but poor H2O tolerance. In this work, cetyltrimethylammonium bromide (CTAB) was used to improve SO2＆H2O resistance over Mo(0.3)-CrCeOx catalyst at medium-low temperatures. The mechanism of CTAB modification and the discrepancy to citric acid (CA) method were investigated. The results indicated that the CTAB catalyst had a large specific surface area, and was conducive to forming a specific structural strength. The enhancement of surface acidity of CTAB is the reason for the further enhancement of SCR activity. The regulation of hydroxyl oxygen to promote the activation of Brønsted acid sites is the key factor to SO2＆H2O resistance. In addition, the in-situ DRIFTS results revealed the different mechanisms of the two catalysts. This paper raised the deactivation reason of sol-gel catalyst caused by SO2＆H2O and presented an effective modification strategy.

Study on antibacterial characteristics and mechanism of synergistic modification of calcined gypsum from phosphogypsum by inorganic antibacterial materials

Mold on the phosphogypsum wallboard seriously hinders the resource utilization of phosphogypsum, and incorporating inorganic antibacterial materials can effectively inhibit mold growth. In this study, Escherichia coli and wallboard mold were used as experimental strains, and the antibacterial activity of antibacterial material-modified calcined gypsum from phosphogypsum (CPG) was determined using the inhibition zone method and mold surface growth area analysis. Characterization techniques such as XRF, XRD, and SEM were used to study the phase composition and microstructure of the samples, and an antibacterial model was constructed to explore the antibacterial mechanism. The results indicated that using E. coli as an indicator bacterium, ZnO-0.05TiO2-CPG exhibited the best bactericidal effect, while ZnO-CPG exhibited the best bacteriostatic effect. Against mold, ZnO contents of 2.5% or 5% demonstrated strong antibacterial properties, with compressive strengths of 10.1 MPa and 9.95 MPa, respectively, meeting the requirements of ≥3.50 MPa for compressive strength according to the ‘Lightweight Partition Plates for Building’ standard (GB/T 23451 2009). The superior antibacterial performance of ZnO compared to TiO2 is attributed to the slow release of Zn2+, which disrupts cell membranes and the generated reactive oxygen species inhibit cell growth.

Insight of indium single atom loading on TiO2 for remarkable photocatalytic hydrogen evolution

Hydrogen production by photocatalysis water splitting is an attractive and promising development method, but the current efficiency is too low for application. Loading single atoms can significantly enhance the photocatalytic efficiency, however, the insightful understanding of the impact of single atom loading on catalytic performance is still ambiguous. In this work, InSA/TiO2 photocatalysts modified with indium single atom (InSA) were synthesized by photo-deposition process. Under 300W Xe lamp illumination, the hydrogen production rate of the optimized InSA/TiO2 photocatalyst achieves 6.11 mmol g−1 h−1, which is 7.6 times that of TiO2 prepared under the same conditions. The results of characterization analysis and density functional theory (DFT) calculations indicate that some of the Ti atoms on the TiO2 surface are replaced by the doped In, and the local electronic structures of the photocatalyst are regulated, which results in effectively separating of the photo-generated carriers, and significant increasing the activity of the surrounding unsaturated oxygen, thus, the photocatalytic hydrogen production performance is effectively improved. This work provides a strategy to improve photocatalytic activity, and also deepens the understanding of metal single atom modification mechanism.

Enhancing Water Tolerance and N2 Selectivity in NH3-SCR Catalysts by Protecting Mn Oxide Nanoparticles in a Silicalite-1 Layer.

Mn-based catalysts are promising candidates for eliminating harmful nitrogen oxides (NOx) via selective catalytic reduction with ammonia (NH3-SCR) due to their inherent strong redox abilities. However, poor water tolerance and low N2 selectivity are still the main limitations for practical applications. Herein, we succeeded in preparing an active catalyst for NH3-SCR with improved water tolerance and N2 selectivity based on protecting MnOx with a secondary growth of a hydrophobic silicalite-1. This protection suppressed catalyst deactivation by water adsorption. Interestingly, impregnating MnOx on MesoTS-1 followed by silicalite-1 protection allowed for a higher dispersion of MnOx species, thus increasing the concentration of acid sites. Consequently, the level of N2O formation is decreased. These improvements resulted in a broader operating temperature of NOx conversion and a modification of the NH3-SCR mechanism. Diffuse reflectance infrared Fourier transform spectroscopy analysis revealed that unprotected Mn/MesoTS-1 mainly followed the Eley-Rideal mechanism, while Mn/MesoTS-1@S1 followed both Langmuir-Hinshelwood and Eley-Rideal mechanisms.

Mitochondrial targeted modification and anticancer mechanism of natural product ergosterol peroxide

Ergosterol peroxide (EP) isolated from the edible medicinal fungus Pleurotus ferulae has a wide range of anti-tumor activity, but poor water solubility and low bioavailability limit further application. In this study, EP was structurally modified using triphenylphosphine (TPP+), which combines mitochondrial targeting, amphiphilicity, and cytotoxicity. A series of TPP+-conjugated ergosterol peroxide derivatives (TEn) with different length linker arms were synthesized. The structure–activity relationship showed that the anticancer activity of TEn gradually decreased with the elongation of the linker arm. The compound TE3 has the optimal and broadest spectrum of antitumor effects. It mainly through targeting mitochondria, inducing ROS production, disrupting mitochondrial function, and activating mitochondria apoptosis pathway to exert anti-cervical cancer activity. Among them, TPP+ only acted as a mitochondrial targeting group, while EP containing peroxide bridge structure served as an active group to induce ROS. In vivo experiments have shown that TE3 has better anti-cervical cancer activity and safety than the first-line anticancer drug cisplatin, and can activate the immune response in mice. Although TE3 exhibits some acute toxicity, it is not significant at therapeutic doses. Therefore, TE3 has the potential for further development as an anti-cervical cancer drug.

Study of electronic properties, mechanical properties and corrosion properties of trace Ce added to Al–Si–Mg–Cu alloys

Corrosion and deformation are one of the main causes of material failure in aluminum alloys, which increases the probability of accidents and causes huge economic losses. In this paper, the mechanism of modification of Al–Si–Mg–Cu alloy by Ce addition was investigated. The effects of common elements in aluminum alloys on Ce solid solution were calculated, in which the ability to promote Ce solid solution in Al was in the following order: Cu＞Mg＞Fe＞Ti＞O＞Si. The changes in the properties of the experimental alloys with different Ce contents were investigated by nanoindentation, tensile test and electrochemistry. The results show that the addition of Ce effectively improves the corrosion resistance and strength of the extruded Al–Si–Mg–Cu alloy. However, the addition of excess Ce decreases the corrosion resistance of the alloy, which was highest with the addition of 0.4 wt% Ce. The Ecorr value is shifted in a positive direction, increasing from the standard electrode potential of Al (−1.66 V) to −0.997 V. In addition, the growth of tensile strength and yield strength becomes slow when the Ce addition exceeds 0.4 %. The results provide technical guidance for the development of new aluminum alloy materials with high corrosion resistance, high strength, and low cost.

Optimizing binders with maximum using of industrial waste to develop low carbon ultra-high performance concrete

Optimizing binders by using industrial waste and then adjusting microstructure has potential to develop low production cost and low carbon emission ultra-high performance concrete (UHPC) to meet different practical engineering requirements. This study first investigates the influence of silica fume, cenosphere and fly ash on paste mixing time, flowability, flexural and compressive strength of UHPC by using three-factor and four-level orthogonal test. Moreover, the effect of fly ash and slag content were further discussed, and the modification mechanisms of binders were revealed by analyzing pore structure, interface and characteristics of hydration products. The results show that silica fume and cenosphere are the most sensitive factors affecting paste mixing time and flowability of UHPC, respectively. The sensitivity of binders on compressive and flexural strength of UHPC can be ranked according to silica fume > fly ash > cenosphere and cenosphere > fly ash > silica fume, respectively. The binders’ composition for low-carbon UHPC with compressive strength grade of 120 MPa is that cement: cenosphere: silica fume: fly ash equals to 1:0.33:0.33:0.56, and the total amount of fly ash reaches 40%. Meanwhile, the 28d compressive/flexural strength decreases and the flowability increases with the increase of fly ash content, resulting from pore volume with size of 5–50 nm and Ca/Si ratio on the interface between steel fiber and matrix increase. The flowability of UHPC with slag is reduced and the cumulative pore volume with size of 50 nm–5 um pores is increased due to the influence of slag morphology, but the porosity and interfacial Ca/Si ratio is reduced because of the high pozzolanic activity of slag, leading to similar compressive and flexural strength with that of UHPC with fly ash.

Methylation Modification in Ornamental Plants: Impact on Floral Aroma and Color.

Methylation represents a crucial class of modification that orchestrates a spectrum of regulatory roles in plants, impacting ornamental characteristics, growth, development, and responses to abiotic stress. The establishment and maintenance of methylation involve the coordinated actions of multiple regulatory factors. Methyltransferases play a pivotal role by specifically recognizing and methylating targeted sites, which induces alterations in chromatin structure and gene expression, subsequently influencing the release of volatile aromatic substances and the accumulation of pigments in plant petals. In this paper, we review the regulatory mechanisms of methylation modification reactions and their effects on the changes in aromatic substances and pigments in plant petals. We also explore the potential of methylation modifications to unravel the regulatory mechanisms underlying aroma and color in plant petals. This aims to further elucidate the synthesis, metabolism, and regulatory mechanisms of various methylation modifications related to the aroma and color substances in plant petals, thereby providing a theoretical reference for improving the aroma and color of plant petals.

Experimental Investigation on the Damage Evolution of Thermally Treated Granodiorite Subjected to Rapid Cooling with Liquid Nitrogen

In many thermal geotechnical applications, liquid nitrogen (LN2) utilization leads to damage and cracks in the host rock. This phenomenon and associated microcracking are a hot topic that must be thoroughly researched. A series of physical and mechanical experiments were conducted on Egyptian granodiorite samples to investigate the effects of liquid nitrogen cooling on the preheated rock. Before quenching in LN2, the granodiorite was gradually heated to 600 °C for two hours. Microscopical evolution was linked to macroscopic properties like porosity, mass, volume, density, P-wave velocity, uniaxial compressive strength, and elastic modulus. According to the experiment results, the thermal damage, crack density, porosity, and density reduction ratio increased gradually to 300 °C before severely degrading beyond this temperature. The uniaxial compressive strength declined marginally to 200 °C, then increased to 300 °C before monotonically decreasing as the temperature rose. On the other hand, at 200 °C, the elastic modulus and P-wave velocity started to decline significantly. Thus, 200 and 300 °C were noted in this study as two mutation temperatures in the evolution of granodiorite mechanical and physical properties, after which all parameters deteriorated. Moreover, LN2 cooling causes more remarkable physical and mechanical modifications at the same target temperature than air cooling. Through a deeper comprehension of how rocks behave in high-temperature conditions, this research seeks to avoid and limit future geological risks while promoting sustainability and understanding the processes underlying rock failure.

Boosting the Electrocatalytic Oxygen Reduction Activity of MnN4-Doped Graphene by Axial Halogen Ligand Modification.

Exploring highly active electrocatalysts as platinum (Pt) substitutes for the oxygen reduction reaction (ORR) remains a significant challenge. In this work, single Mn embedded nitrogen-doped graphene (MnN4) with and without halogen ligands (F, Cl, Br, and I) modifying were systematically investigated by density functional theory (DFT) calculations. The calculated results indicated that these ligands can transform the dyz and dxz orbitals of Mn atom in MnN4 near the Fermi-level into dz2 orbital, and shift the d-band center away from the Fermi-level to reduce the adsorption capacity for reaction intermediates, thus enhancing the ORR catalytic activity of MnN4. Notably, Br and I modified MnN4 respectively with the lowest overpotentials of 0.41 and 0.39 V, possess superior ORR catalytic activity. This work is helpful for comprehensively understanding the ligand modification mechanism of single-atom catalysts and develops highly active ORR electrocatalysts.

Research on the wear resistance and impact resistance of modified rubberized concrete

Rubber can improve the ductility and durability of concrete and reduce compressive strength. Tests were conducted to investigate the mechanical properties, wear resistance, and impact resistance of modified rubberized concrete (MRC) by mixing basalt fibers (BF), curing agent, and epoxy resin mixture. The results showed that the epoxy polymer improved the flowability of the rubberized concrete. The BF changed the failure mode of the rubberized concrete and enhanced the mechanical properties. When the curing agent-epoxy resin ratio was 4:8, the wear rate of BF6E8C4 after 120 times was 4.59 kg/m2, which was 70.02% and 3.77% less than that of BF2E8C4 and BF4E8C4. The impact strength of BF6E8C4 was increased by 256% and 409% compared with the BF2E8C4 and BF4E8C4, respectively. By analyzing the mechanism of the synergistic modification of BF and epoxy polymer, it was found that the synergistic work of BF and epoxy polymer could make the internal structure of concrete denser. At last, the wear damage and impact damage models of MRC were established, and the coefficient of determination exceeded 0.92.

Synergistic enhancement of rheological and anti-aging properties of asphalt modified with bio-oil and layered silicate

Applying bio-oil to asphalt pavement effectively reduces the dependence on traditional petroleum asphalt in pavement industry. However, the utilization of bio-oil can encounter rutting and aging issue of modified asphalt. To solve the aforementioned issue, two kinds of organic layered silicates with typical structures were adopted to enhance the high-temperature and anti-aging performance of the bio-modified asphalt. The modification mechanism and the synergistic effect of bio-oil and organic layered silicate on asphalt were explored through rheological characterization, infrared spectroscopy tests, gel chromatography tests, etc. Results showed that the incorporation of layered silicate in bio-modified asphalt can improve asphalt-filler interaction and hence the high-temperature and fatigue performance of asphalt. When the content of layered silicate is 5 %, the negative effect of Castor oil on the high-temperature performance of asphalt can be eliminated. Still, for Turpentine wood oil and Straw oil, the content of layered silicate is 7 %, which shows the same effect. The waste bio-oils can balance the low-temperature performance of asphalt modified with layered silicates. Furthermore, the addition of layered silicates was effective to reduce oxidation reaction and improve the anti-aging performance of bio-oil modified asphalt. When the ratio of layered silicate to bio-oil is 1 1, the composite-modified asphalt maintains the best anti-aging performance. Specifically, Castor oil, Straw oil, and OMMT are more suitable, and Turpentine wood oil and OREC are more appropriate. According to the quantification of the functional group aging index, the SI and CI of the optimal ratio of different types of bio-oil asphalt are Castor oil: 61.64 % and 59.41 %, Turpentine wood oil: 50.02 % and 53.57 %, Straw oil: 50.01 % and 55.05 %. Composite modified asphalt can be applied to complex service conditions.

Modified Bentonite As a Dissolve-Extrusion Composite and Its Modification Mechanism.

In the geological core drilling industry, simple and low-cost drilling fluid formulations are required that are easy to apply and maintain. Currently, drilling fluid systems with simple formulations generally exhibit poor performance and do not satisfy the requirements of complex formations. The application of powder surface modification technology has been extensively investigated in several fields; however, few are the studies focusing on the modification of bentonite. Consequently, in this study, based on the surface modification technology of powders, bentonite is modified using the modifiers ZJ-1 and ZJ-2, giving it the characteristic of "one additive with multiple functions". This allows the construction of a new type of drilling fluid system with a simple formulation (water + modified bentonite), excellent performance, and easy application and maintenance. First, a new composite modification method named the dissolution and extrusion composite modification method was proposed, and the dosage of the modifier and the optimal ratio of each modifier were determined experimentally. Second, orthogonal design experiments were conducted to determine the optimal preparation conditions based on the rheological properties of the drilling fluid, dynamic plastic ratio, and filtration loss. Subsequently, the performance of the modified bentonite drilling fluid was analyzed by comparing it to that of a regular bentonite drilling fluid. Finally, the modification mechanism of bentonite was analyzed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). It was revealed that a total modifier dosage of 2% and a ratio of ZJ-1 to ZJ-2 of 1.5:0.5 afforded a modified bentonite drilling fluid with significantly enhanced performance compared to a regular bentonite drilling fluid. The modified bentonite exhibited a filtration loss of 7.5 mL, funnel viscosity of 51.5 s, static shear force of 2.5 Pa, dynamic shear force of 9.198 Pa, apparent viscosity of 29 mPa·s, and plastic viscosity of 20 mPa·s. The experimental repeatability was good, and the optimal preparation conditions for modified bentonite involved a reaction time of 10 h, a reaction temperature of 100 °C, and a mechanical pressure of 0.5 MPa. Microscopic analysis showed that the modifiers were incorporated into bentonite through intercalation and surface adsorption and that the modified bentonite can form a dense filter cake. Our study provides a new drilling fluid solution for the geological core drilling industry, effectively promoting the advancement of drilling fluid technologies.

Laboratory evaluation of performances and thermo-oxidative aging characteristics of high-viscosity modified asphalt

High construction temperatures and complex application conditions make the high-viscosity modified asphalt (HVMA) susceptible to aging. This work presents a comprehensive investigation of the performances and thermo-oxidative aging characteristics of HVMA. Fistly, an instant high-viscosity modifier (HVM) was synthesized and then optimized by entropy weight method. The modification mechanism and high- and low-temperature performances of HVMAs were investigated by the Fourier transform infrared spectroscopy (FTIR), temperature sweep, and low temperature creep tests. Besides, thermo-oxidative aging characteristics were evaluated by the frequency sweep, multiple stress creep recovery (MSCR) and fluorescence microscopy (FM) tests. Results shows that the recommended formulation of instant HVMA (HVMA-I) was 12 % instant HVM and 0.2 % stabilizer. Grafting and cross-linking reactions involved in HVMA-I, thus ensuring the excellent high- and low-temperature performances. The thermo-oxidative aging of HVMA consisted of the modifier degradation and the binder oxidation. Short-term aging produced a marginal effect as a fluctuating change direction for complex modulus. Long-term aging had pronounced effects on the performances of HVMA. At the macroscopic level, the complex modulus was increased and the nonrecoverable creep compliance was decreased; at the microscopic level, the fluorescence area was reduced and phase network was degraded.

Property improvement of epoxy emulsified asphalt modified by waterborne polyurethane in consideration of environmental benefits

Waterborne epoxy modified emulsified asphalt (EMEA) has the shortcomings of insufficient toughness and poor aging resistance, which limits its application of low-carbon cold-paving technology in plateau zones. To obtain a cold-mix asphalt binder with excellent performance, waterborne polyurethane (WPU) was utilized to modify EMEA in this work. Properties, modification mechanism, action process, environmental benefits, and cost-benefit of composite-modified emulsified asphalt (CMEA) were analyzed. Results show that CMEA had good rutting resistance, low-temperature rheological, tensile toughness, adhesion with aggregate and moisture damage resistance, and aging resistance properties. These were closely related in that WPU was cross-linked with the waterborne epoxy resin (WER) to form an interpenetrating polymer network (IPN) structure, when the space network structure of WER and the soft and hard segments of WPU worked together. Based on the above results, it was recommended that EA containing 4.0 wt% WER was modified by 7.5 wt% WPU to achieve the best pavement properties. Furthermore, it was discovered that a physical process by which WER and WPU modified EA, served as a skeleton connection and toughening agent. CMEA has excellent performance and is especially suitable for use in low-temperature and strong aging areas, while can bring good environmental benefits.

Effects and Modification Mechanisms of Different Plasma Treatments on the Surface Wettability of Different Woods

Plasma treatment of wood surfaces has shown significant effects, but different excitation methods used for different species of wood generally result in varied characteristics of wood surfaces. Secondly, plasma modification greatly enhances the absorption of liquids by wood, but the relationship between liquid absorption and surface wettability is rarely studied. Limited detailed investigation of the modification effects and mechanisms has hindered the large-scale applications of plasma treatment in the wood industry. In this study, two typical plasmas, radio frequency (RF) plasma and gliding arc discharge (GAD) plasma, were employed to treat three species of wood: poplar, black walnut, and sapele. By focusing on changes in the contact angle of the wood surface, an exponential equation fitting method is used to determine the measurement time for contact angles. The research identified that factors contributing to the decrease in contact angle after plasma modification include not only the increase in surface energy but also liquid absorption. SEM and XPS analyses demonstrate that plasma etching accelerated liquid absorption by modifying the surface topography, while the increase in surface energy was due to the addition of oxygen-containing groups. High-valence C=O and O-C=O groups serve as indicators of plasma-induced surface chemical reactions. RF modification primarily features surface etching, whereas GAD significantly increases the active surface groups. Thus, different plasmas, due to their distinct excitation modes, produce diverse modification effects on wood. Considering the various physical and chemical properties of plasma-modified wood surfaces, recommendations for adhesive use on plasma-modified wood are provided.

Robust superhydrophobic self-cleaning coating prepared by silane modified multi-walled carbon nanotubes: A combined experimental and molecular dynamics study

As a functional material, superhydrophobic coating has been widely studied in the field of self-cleaning. However, obtaining superhydrophobic coatings with robustness through simple preparation processes remains a challenge. In this paper, a robust superhydrophobic coating is prepared based on multi-walled carbon nanotubes modified by octyltrimethoxysilane, and its performance and hydrophobic mechanism are studied by experiments and molecular dynamics simulation. The superhydrophobic coating is prepared by one-step spraying method. The coating is characterized and analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy, and the properties of the coating are tested by experiments. Molecular dynamics simulation is used in the study to construct a molecular model system, and the molecular modification mechanism and coating wettability are simulated under the COMPASSII force field. The results show that octyltrimethoxysilane successfully modified carbon nanotubes, and the hydroxyl groups at the head of the molecular chain are bound to the surface of the carbon nanotubes in the form of hydrogen bonds, while the tail of the molecular chain is far away from the surface. After modification, the surface of carbon nanotubes changed from hydrophilic to hydrophobic. The prepared superhydrophobic coating not only has excellent self-cleaning properties, but also exhibits corrosion resistance to acid and alkali solutions. The coating still has superhydrophobic when the wear length is in the range of 400 cm. It can be seen that a robust superhydrophobic self-cleaning coating is successfully prepared by a simple one-step spraying method. The modification mechanism and the hydrophobic mechanism of the coating were obtained by the combination of experiment and molecular dynamics simulation, which provided theoretical support for the superhydrophobic of the coating at the micro level.