The freezing and thawing of construction concrete is becoming an increasingly important structural challenge. In this study, a shrinkage-compensating concrete based on a double expansive admixture was developed and its frost resistance was assessed through rapid freezing and thawing cycling. The frost resistance of the concrete was derived through the measurement and calculation of the relative dynamic modulus of elasticity (RDME) and the mass loss rate (MLR), and the freezing- and thawing-cycle microstructures and products of concretes with different expansive agents were analyzed using scanning electron microscopy (SEM). It was shown that changes in the properties of the concrete under freezing and thawing could be divided into three stages: slow-damage stage, fast-damage stage, and stable stage. Compared to concrete without an expansive agent, a single-expansive-agent concrete demonstrated excellent frost resistance during the slow-damage stage, but the frost resistance rapidly decreased during the fast-damage age. After 150 cycles (the stable-damage stage), the concrete with a U-type expansive agent (UEA): MgO expansive agent (MEA) mix proportion of 2:1 had the best frost resistance, with RDME and MLR values 17.35% higher and 25.1% lower respectively, than that of an expansive-agent-free concrete. These test results provide a basis for the study of frost resistance in large-scale hydraulic concrete structures.
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http://dx.doi.org/10.3390/ma13081850 | DOI Listing |
Plant Physiol Biochem
January 2025
Shandong Institute of Pomology, Shandong Academy of Agricultural Sciences, Taian, 271000, China. Electronic address:
Frost damage to apple flowers significantly affects both the quality and yield of apples, potentially leading to substantial economic losses. This study investigates the application of the environmentally friendly plant hormone 24-epibrassinolide (EBR) on apple flowers to assess its effects under frost stress conditions. The findings indicate that exogenous EBR treatment maintained favorable flower morphology, mitigated pistil browning, and reduced ion leakage.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources; College of Chemistry, Xinjiang University, Urumqi, 830017, Xinjiang, PR China; School of Materials Science and Engineering, Xinjiang Engineering Research Center of Environmental and Functional Materials, Xinjiang University, Urumqi, 830017, Xinjiang, PR China. Electronic address:
Antibiotic residues pose a significant threat to global health. Traditional detection methods for antibiotics are cumbersome, time-consuming and often incapable of achieving non-destructive detection at low temperatures. This research introduces a groundbreaking innovation in antibiotic detection: a flexible Surface-Enhanced Raman Scattering substrate based on a silver composite deep eutectic solvent (DES) gel, specifically engineered for low-temperature antibiotic detection.
View Article and Find Full Text PDFPlants (Basel)
January 2025
College of Life Sciences, Shihezi University, Shihezi 832000, China.
Plants have large amounts of the late embryogenesis abundant protein (LEA) family of proteins, which is involved in osmotic regulation. The Korla Pear () is an uncommon pear species that thrives in Xinjiang and can survive below-freezing conditions. We found that the gene was more expressed after cold treatment by looking at the transcriptome data of the Korla Pear.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
School of Civil Engineering and Transportation, Northeast Forestry University, Harbin 150040, China.
This article systematically investigated the improvement effect of polypropylene fiber (PPF) on the mechanical and freeze-thaw properties of alkali-activated fly ash slag concrete (AAFSC) with high fly ash content and cured at room temperature. Fly ash and slag were used as precursors, with fly ash accounting for 80% of the total mass. A mixed solution of sodium hydroxide and sodium silicate was used as alkali activator, and short-cut PPF was added to improve the performance of AAFSC.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Department of Inorganic and Analytical Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91-403 Lodz, Poland.
The aim of this research was to obtain two-layer polymer composites with favorable mechanical and functional properties. The composites consisted of one lower layer of polymer with less elastic properties, containing no admixtures, and one upper layer of polymer with more elastic properties, containing plant admixtures, in the amount of 10% by weight of either goldenrod ( L.), or of turmeric ( L.
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