Materials
·
2024
·Vol. 17
·期 13
·3137
·
IF 3.1
Yitong Hou,Kaimin Niu,Bo Tian,Junli Chen,Xueyang Li
To develop a cement emulsified asphalt composite (CEAC) that can be sprayed under a plateau negative temperature environment, the effects of the water–solid ratio, calcium aluminate cement substitution rate, emulsified asphalt content, sand–binder ratio, and polyvinyl alcohol (PVA) fiber content on the spraying performance and rheological parameters of CEAC were explored through the controlled variable method. Additionally, the correlation between the spraying performance and rheological parameters of CEAC was established, and the optimal proportion of CEAC was determined. Then, the difference in frost resistance and pore structure between the cement slurry (CS) without emulsified asphalt and CEAC at the optimum proportion was analyzed. The results showed that the optimum proportions for sprayed CEAC were 0.14 water–solid ratio, 0.5 sand–binder ratio, 25% substitution of calcium aluminate cement, 5% emulsified asphalt content, and 1.5% PVA fiber volume mixing. The yield stress and plastic viscosity of CEAC were positively correlated with the build-up thickness, whereas the rebound rate and the latter showed a negative correlation. The spraying performance may be described by the rheological parameters; the ranges of yield stress and plastic viscosity of 2.37–3.95 Pa·s and 77.42–108.58 Pa, respectively, produced the best spray ability. After undergoing an equivalent number of freeze–thaw cycles, CEAC exhibited lower mass and strength loss rates compared to CS, thereby demonstrating superior frost resistance. In addition, the pore structure analysis showed that the difference in capillary and macropore contents was the main reason for the variability in frost resistance between CS and CEAC.
研究领域:
土木工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2019
·
IF 4.046
Mingxu Chen,Laibo Li,Jiaao Wang,Yongbo Huang,Shoude Wang,Piqi Zhao,Lingchao Lu,Xin Cheng
Recent advances have proposed new requirements on the controlling of the hydration, the rheology, and the structural build-up of 3D printing (3DP) sulphoaluminate cement (SAC) paste. In this study, the boric acid (BA), the sodium gluconate (SG), and the diatomite were used to control these behaviors of 3DP SAC paste , and the printed structures could be well built based on the extrusion system. The results show that the building time and printability can be improved by the introduction of BA and SG into SAC paste, but the excessive dosage will cause the structural failure. To decrease the structural deformation of 3DP SAC paste, the diatomite was applied to increase the static yield stress and elasticity modulus. Meanwhile, a paste sample with the structural deformation less than 10% can be achieved when the static and dynamic yield stress was controlled in the range of 590–895 Pa, and 509–722 Pa, respectively. In conclusion, the 3D printed structures and rheology could be well controlled by the introduction of retarders and diotomite in the 3DP SAC paste.
研究领域:
土木工程
·
材料科学
·
3D打印技术
✓ 已验证
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Wenting Shang,Xin Li,Jinyu Du,Yuxin Guo,Dekun Fu,Yanfu He,Fei Pan,Weimin Zhang,Zhongkai Zhou
Effect of complexation of three medium-chain fatty acids (octanoic, decylic and lauric acid, OA, DA and LA, respectively) on structural characteristics, physicochemical properties and digestion behaviors of cassava starch (CS) was investigated. Current study indicated that LA was more easily to combine with CS (complex index 88.9%), followed by DA (80.9%), which was also consistent with their corresponding complexed lipids content. Following the investigation of morphology, short-range ordered structure, helical structure, crystalline/amorphous region and fractal dimension of the various complexes, all cassava starch-fatty acids complexes (CS-FAs) were characterized with a flaked morphology rather than a round morphology in native starch (control CS). X-ray diffraction demonstrated that all CS-FAs had a V-type crystalline structure, and nuclear magnetic resonance spectroscopy confirmed that the complexes made from different fatty acids displayed similar V6 or V7 type polymorphs. Interestingly, small-angle X-ray scattering analysis revealed that α value became greater following increased carbon chain length of fatty acids, indicating the formation of a more ordered fractal structure in the aggregates. Changes in rheological parameters G′ and G′′ indicated that starch complexed with fatty acids was more likely to form a gel network, but difference among three CS-FAs complexes was significant, which might be contributed to their corresponding hydrophobicity and hydrophilicity raised from individual fatty acids. Importantly, digestion indicated that CS-LA complexes had the lowest hydrolysis degree, followed by the greatest RS content, indicating the importance of chain length of fatty acids for manipulating the fine structure and functionality of the complexes.
研究领域:
食品科学
·
分子模拟
·
营养学
·
生物物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）