Article
Construction & Building Technology
Hongwei Zhu, Zihao Qin, Zhibo Ma, Fazhou Wang, Chuanlin Hu
Summary: Novel C-F-S-H/PCE nanocomposites were successfully synthesized by incorporating Fe3+ during the synthesis of C-S-H/PCE. These nanocomposites showed high-efficiency seeding effect on early cement hydration due to the higher absorption of PCE and smaller particle size of nano-seeds compared to traditional C-S-H/PCE nanocomposites. The best seeding effect was observed when the Ca/Si and Fe/Si ratios were 1.0 and 0.03 respectively.
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Chemistry, Physical
Jiayu Mo, Antonis M. Messinis, Joao C. A. Oliveira, Serhiy Demeshko, Franc Meyer, Lutz Ackermann
Summary: The C-H/C-C functionalization with oxymethylated bicyclopropylidenes using an iron catalyst under external oxidant-free conditions led to the synthesis of various pharmacologically active compounds. The mechanism involving C-C cleavage via beta-C elimination was supported by mechanistic studies, and a rare monoselective C-F/C-H bond functionalization of trifluoromethylarene was observed.
Article
Construction & Building Technology
Matheus Ian Castro Sousa, Joao Henrique da Silva Rego
Summary: By studying the combined effect of Metakaolin and Nanosilica in different ratios, this research found that ternary mixtures with OPC had higher strength values, lower portlandite content, and increased C-A-S-H content with longer molecular chains. A synergistic effect between nanosilica and metakaolin, dependent on their ratio in paste composition, was observed.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Construction & Building Technology
Jinpeng Jia, Nanyan Hu, Yicheng Ye, Nan Yao, Yang Huang, Fanghui Fu
Summary: A novel strategy has been proposed to fabricate C/M-S-H cementitious materials from phosphate tailings, aiming to reduce CO2 emissions in cement preparation. an experimental program was conducted using TG, XRD, SEM, and strength evaluation to study the dehydration and hydration behavior of C/M-S-H. The results showed that appropriate dehydration temperatures and additions could increase early hydration reactivity, improving the concrete's performance.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Multidisciplinary
Yanru Wang, Yubin Cao, Zuhua Zhang, Jizhong Huang, Peng Zhang, Yuwei Ma, Hao Wang
Summary: In this study, two typical binding gels in AAMs, N-A-S-H and C-(N)-A-S-H, were chemically prepared and investigated for their microstructure and composition evolution when exposed to sulfuric acid. The results showed that both gels had increased silica polymerization degree after exposure to sulfuric acid solution, with N-A-S-H gel showing faster dealumination and higher Si/Al ratio increase. The molecular framework changes caused by dealumination in the N-A-S-H gel had less effect on integrity compared to C-(N)-A-S-H gel, where coarse gypsum crystalline grains formed and led to destructive stress in hardened matrix.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Construction & Building Technology
Achutha Prabhu, Jorge S. Dolado, Eddie A. B. Koenders, Rafael Zarzuela, Maria J. Mosquera, Ines Garcia-Lodeiro, Maria Teresa Blanco-Varela
Summary: The proposed coarse graining approach using patchy particles and a modified Patchy Brownian Cluster Dynamics algorithm successfully simulated the formation of C-S-H, showing qualitative kinetic evolution and comparable final structures to previous studies. The model extension to study the role of water in tetraethoxysilane oligomers polymerization also yielded results in good agreement with experiments.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Laura Koering, Arne Stepen, Bernhard Birenheide, Simon Barth, Maxim Leskov, Roland Schoch, Felix Kraemer, Frank Breher, Jan Paradies
Summary: A series of redox-responsive ferrocenyl-substituted boranes and boronic esters were synthesized, and the oxidation of the ferrocenyl ligand to the ferrocenium increased the Lewis acidity beyond the strength of SbF5. This was investigated experimentally and computationally, and the resulting highly Lewis acidic boron compounds were used for catalytic C-F and S-F bond activation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Construction & Building Technology
Han Zhou, Wenxiao Lv, Jiawei Jiao, Duyou Lu, Dongxu Li
Summary: In this study, C-A-S-H with varying Li contents were synthesized via hydrothermal method, with the incorporation of Li leading to changes in interlayer distance, crystallinity, and polymerization degree. The specific surface area of C-(Li)-A-S-H decreased significantly with the addition of LiOH, and the formation of katoite on the surface at high LiOH concentrations altered the pore structure. The Ca/Li ratio was identified as a key parameter for successful Li incorporation into C-A-S-H.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Lina Bouzouaid, Barbara Lothenbach, Alejandro Fernandez-Martinez, Christophe Labbez
Summary: This study investigates the effect of different organic compounds on the solubility of C-S-H, finding that they can form complexes with calcium and hydroxide, with gluconate showing the highest complexation strength. The adsorption order is gluconate > sorbitol > mannitol > galactitol, and a typical adsorption isotherm is found only when buffered with Ca(OH)(2).
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Mohammad Amiri, Mahmood Sanjari, Fatemeh Porhonar
Summary: Red soil, commonly used as pavement material in southern Iran, can be improved by adding cement, which promotes the formation of Calcium Ferrite Hydrate (C-F-H) and ilavite (C-F-S-H), enhancing the stability and compressive strength of the soil.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Computer Science, Artificial Intelligence
J. Jayapradha, M. Prakash
Summary: The research introduces a model called f-slip that tackles various attacks in 1:M datasets and proposes solutions. By anatomizing and slicing the dataset, it can protect sensitive attributes effectively and implement k-anonymity.
Article
Chemistry, Organic
Pavel S. Gribanov, Daria V. Vorobyeva, Sergey D. Tokarev, Dmitry A. Loginov, Anastasya A. Danshina, Salekh M. Masoud, Sergey N. Osipov
Summary: An efficient pathway to a new family of fluorinated polyheteroaromatic D-A molecules has been developed. This method allows the modification of the acceptor block and provides a good yield of the target D-A systems. The discovery of different reactivity between aryl boronic reagents enables the divergent modification of the BTD acceptor block through ortho-selective C-F activation.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Zhipeng Guan, Shuxiang Zhu, Yankai Yang, Yanlong Liu, Siyuan Wang, Faxiang Bu, Hengjiang Cong, Hesham Alhumade, Heng Zhang, Aiwen Lei
Summary: The study demonstrates a new method for formation of C(sp(2))-S/Se and C(sp(2))-N bonds with isocyanides, providing access to novel multiple isothioureas and rare selenoureas. The protocol shows good atom-economy and step-economy, with theoretical calculations explaining the stereoselectivity of products. The electrochemical reaction specifically occurs at the isocyano part, regardless of the presence of radical acceptors.
Article
Chemistry, Multidisciplinary
Philipp Dabringhaus, Ingo Krossing
Summary: This study reports the synthesis of AlCp*-complexes with low-valent main-group metals, including the first covalent Al-In and Al-Tl bonds. The Ga complex exhibits a solvent and temperature dependent equilibrium between monomeric and dimeric forms, while the In and Tl complexes are monomeric and can be reduced by AlCp*. Addition of Me(3)TACN leads to the isomerization to a novel low-valent Al-4(+) cation. This research provides valuable insights into the reactivity of metal-main-group element complexes.
Article
Construction & Building Technology
Xin Liu, Pan Feng, Xiaohan Yu, Xuyan Shen, Guoqing Geng, Barbara Lothenbach
Summary: This study comprehensively analyzes the effects of magnesium on the physiochemical properties of C-S-H. The stability of C-S-H is impaired under magnesium attack, leading to the precipitation of M-S-H and brucite on its surface. The dominance of M-S-H phase increases with higher magnesium concentrations. The Ca/Si and Mg/Si ratios of hydrates increase with the Ca/Si ratio of starting C-S-H samples. A small amount of magnesium may enter the C-S-H structure after exposure to magnesium solution, presenting a different binding energy compared to pure M-S-H. Anion types have a limited influence on the deterioration of C-S-H, except when sulfate ions are present and gypsum is observed.
CEMENT AND CONCRETE RESEARCH
(2022)
