CONSTRUCTION AND BUILDING MATERIALS
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2024
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IF 7.4
Meijie Liao,Lei Luo,Yingli Gao,Zhengkang Li,Pengfei Liu
SBS modified asphalt is widely used due to its excellent performance at both high and low temperatures, but its water resistance still needs improvement. To enhance its moisture damage resistance, this study modified SBS asphalt with three hydrophobic materials: polytetrafluoroethylene (PTFE), hydrophobic nano-SiO 2 , and trimethoxymethylsilane (MTMS). Viscosity tests, FTIR analysis, and the Langmuir water diffusion model were used to evaluate the modification effects. The results showed that all three hydrophobic materials effectively reduced viscosity changes of the asphalt in neutral rainwater, seawater, and acid rain.the hydrophobic modifiers significantly enhanced the stability and deformation resistance of SBS modified asphalt mixtures (by 57.7 %, 43.5 %, and 30.5 %) During water aging, asphalt undergoes saturated hydrocarbon degradation and unsaturated functional group oxidation, which is accelerated by acid rain and seawater. PTFE delayed asphalt degradation through crosslinking, while nano-SiO 2 and MTMS formed a Si-O-Si network, reducing water and oxygen diffusion, thereby improving water aging resistance. The hydrophobic modification significantly lowered the asphalt's water absorption and diffusion rate, preventing moisture from reaching the asphalt-aggregate interface. Aging-generated functional groups like carboxyl and ether groups intensified internal moisture diffusion, but the hydrophobic materials effectively delayed aging and prevented water penetration. This study reveals the modification mechanisms of hydrophobic materials in complex water environments, providing theoretical support for improving SBS asphalt's water damage resistance.
研究领域:
土木工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2025
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IF 4
Wenhui Lu,Jing Chen,Liangliang Zhang,Zixuan Nie
Determining the temporal evolution of inks remains a critical challenge in forensic document analysis. The temporal evolution stages classification and aging time prediction of gel-pen ink were investigated by integrating gas chromatography-ion mobility spectrometry (GC-IMS) with machine learning algorithms. Ink-specific volatile markers were correlated with aging mechanisms through kinetic modeling and heatmap analysis. Three distinct temporal evolution stages were categorized into the rapid evaporation stage, slow-release stage, and chemical stabilization stage through multivariate analysis of volatiles. Furthermore, six tree-based machine learning algorithms were systematically evaluated, with the Categorical Boosting (CatBoost) model achieving superior performance (accuracy=100 %) in classifying five detailed aging stages of gel-pen ink. The decision tree regression model demonstrated high temporal prediction accuracy (test R²=0.954) through interpretable feature engineering. A stepwise strategy combining classification and regression models was proposed, enabling simultaneous ink characterization and age estimation. This methodology is expected to provide a validated approach for classifying temporal evolution stages and predicting aging time, significantly improving the efficiency of forensic analysis in judicial investigations.
研究领域:
分析化学
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法医学
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数据科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Zhejiang University-SCIENCE B
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2021
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IF 3.066
Zhiwei SU,Mingxing LI,Ling ZHANG,Chaoyang WANG,Leiqing ZHANG,Jingqiu XU,Baiping FU
Objective To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength (SBS). Methods A silica-zirconia suspension was prepared and used to coat a zirconia surface using a dip-coating technique. One hundred and eighty-nine zirconia disks were divided into three groups according to their different surface treatments (polishing, sandblasting, and silica-zirconia coating). Scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) were used to analyze the differently treated zirconia surfaces. Different primer treatments (Monobond N, Z-PRIME Plus, and no primer) were also applied to the zirconia surfaces. Subsequently, 180 composite resin cylinders (Filtek Z350) were cemented onto the zirconia disks with resin cement (RelyX Ultimate). The SBS was measured after water storage for 24 h or 6 months. The data were analyzed by two-way analysis of variance (ANOVA). Results SEM and EDX showed that the silica-zirconia coating produced a porous layer with additional Si, and XRD showed that only tetragonal zirconia was on the silica-zirconia-coating surface. Compared with the control group, the resin-zirconia SBSs of the sandblasting group and silica-zirconia-coating group were significantly increased ( P <0.05). The silica-zirconia coating followed by the application of Monobond N produced the highest SBS ( P <0.05). Water aging significantly reduced the resin-zirconia SBS ( P <0.05). Conclusions Dip-coating with silica-zirconia might be a feasible way to improve resin-zirconia bonding.
研究领域:
牙科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Qiliang Zhu,Wenxuan Huang,Jianhua Shen,Haibo Jiang,Yihua Zhu,Chunzhong Li
Metal halide perovskite nanocrystals have garnered significant attention in the realm of photocatalytic CO 2 reduction in recent years owing to their remarkable reducing properties and high selectivity. However, the issue of low photocatalytic activity due to severe carrier recombination phenomena in perovskite has posed a significant challenge. To address this, a one-pot in-situ preparation strategy was employed to create a BiOBr/Bi-doped perovskite nanocrystal S-scheme heterojunction, resulting in a significant improvement in the CO 2 photoreduction performance. The heterojunction material exhibited a CO yield of 151.56 μmolg -1 h −1 , with a selectivity for CO of 93.6 %. The molar ratio of the components was modulated using an in-situ water aging strategy, yielding a photocatalyst performance that exceeded that of pure BiOBr. The synthesis strategy of one-step in-situ preparation of heterojunctions overcomes the problem of insufficient bonding caused by two-step methods. And various characterizations and DFT calculations strongly support the S-scheme mechanism of the photocatalyst. The active site effectively reduces the energy barrier for the transition from *COOH to *CO intermediate, thereby significantly improving photocatalytic activity.
研究领域:
材料科学
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光催化
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纳米技术
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）