Searched for: subject%3A%22Silica%22
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Döpke, M.F. (author)
Experimentally investigating the nanoscale behavior at oxide-electrolyte interfaces has proven to be extremely challenging. Molecular Dynamics (MD) simulations have arisen as a potential computational alternative to gain atomic level insights at these interfaces. But how accurately do these simulations represent the physics and chemistry at the...
doctoral thesis 2023
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Kianfar, B. (author), Hassanizadeh, S. Majid (author), Abdelrady, Ahmed (author), Bogaard, T.A. (author), Foppen, J.W.A. (author)
In the terrestrial environment, interactions between natural organic matter (NOM) and colloids can lead to the formation of an environmental corona around colloids, influencing their transport behaviour and, ultimately, their ecotoxicity. We used a synthetically designed colloid tagged with DNA (DNAcol) as a surrogate for natural colloids and...
journal article 2023
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Kim, S. (author), Dierkes, Wilma K. (author), Blume, Anke (author), Talma, Auke (author), van Ommen, J.R. (author), Courtois, Nicolas (author), Davin, Julian (author), Recker, Carla (author), Schoeffel, Julia (author)
Pre-treated silica with a plasma-deposited (PD) layer of polymerized precursors was tested concerning its compatibility with Natural Rubber (NR) and its influence on the processing of silica-silane compounds. The modification was performed in a tailor-made plasma reactor. The degree of deposition of the plasma-coated samples was analyzed by...
journal article 2023
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Kianfar, B. (author), Tian, Jingya (author), Rozemeijer, Joachim (author), van der Zaan, Bas (author), Bogaard, T.A. (author), Foppen, J.W.A. (author)
In recent years, DNA-tagged silica colloids have been used as an environmental tracer. A major advantage of this technique is that the DNA-coding provides an unlimited number of unique tracers without a background concentration. However, little is known about the effects of physio-chemical subsurface properties on the transport behavior of...
journal article 2022
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Haidari, A.H. (author), Witkamp, G. J. (author), Heijman, Sebastiaan (author)
Silica scaling is one of the major scaling challenges in Reverse Osmosis (RO). The safe operation practice is to keep the silica concentration below 150 mg/L in RO concentrate. This study addresses the effects of divalent cations such as calcium and magnesium on silica scaling in a seawater RO installation used as a pretreatment to Eutectic...
journal article 2022
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Qiu, Xiujiao (author), Chen, J. (author), Ye, G. (author), De Schutter, Geert (author)
A 3D reactive transport model at microscale is proposed for simulating the chemical reaction process of alkali silica reaction (ASR) thermodynamically and kinetically including the dissolution of reactive silica, the nucleation and growth of ASR products and the dissolution of calcium hydroxide (CH) and calcium silicate hydrate (C-S-H) as a...
journal article 2022
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Qiu, Xiujiao (author), Chen, J. (author), Ye, G. (author), De Schutter, Geert (author)
Prediction of alkali silica reaction is still difficult due to the lack of a comprehensive understanding of its chemical fundamentals. In-site experimentally revealing the fundamentals is not realistic as ASR shows over several years or even decades and is affected by many factors. In this paper, by utilizing a 3D reactive-transport...
journal article 2022
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Kongshaug, Simen Sørgaard (author), Hendriks, M.A.N. (author), Kanstad, Terje (author), Markeset, Gro (author)
Alkali–silica reaction (ASR) in concrete causes expansion and degradation of the material, which might give adverse structural consequences. From the structural engineer point view, the greatest concern is if ASR leads to loss of structural integrity. Two natural questions arise when assessing existing concrete structures affected by ASR: (1)...
journal article 2022
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Chakraborty, S. (author), Foppen, J.W.A. (author), Schijven, Jack F. (author)
We investigated the transport and retention kinetics of silica encapsulated – silica core double stranded DNA particles (SiDNASi) through 15cm saturated quartz sand columns as a function of a wide range of colloid injection concentrations (C0 = 8.7×102 - 6.6×108 particles ml-1). The breakthrough curves (BTCs) exhibited an overall 2-log increase...
journal article 2022
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Weijers, M.J. (author), Karanth, P. (author), Ganapathy, S. (author), Mulder, F.M. (author)
Nanostructured solid composite electrolyte or nano-SCE, which is composed of an ionic liquid, nanoporous silica, and residuals of immobilized precursor components, shows promising synergistic properties. The ionic conductivity of nano-SCE is in the range of 2–5 mS cm<sup>−1</sup>, which exceeds the bulk ionic liquid conductivity at ambient...
journal article 2022
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Roza, Rintati (author)
This thesis aims to find out whether electrokinetic transport of a calcium chloride solution can be controlled by adding sodium ions by performing molecular dynamics simulations. The idea that electrokinetic transport control is a possibility originates from research that found that charge inversion is reduced when monovalent ions are added to a...
master thesis 2021
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Ni, Chenxin (author), Yu, Zhuqing (author), Shen, Xiaodong (author)
As one of the mineral admixtures, silica fume (SF) with high pozzolanic reactivity is generally used to improve the properties of concrete. Most commercial silica fume used in concrete project is dry densified silica fume (DSF). It consists of a good deal of agglomerates of sizes ranging from 10 μm to several millimeters. The size of the...
conference paper 2021
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Shi, Zhenguo (author), Lothenbach, Barbara (author)
Using Al-rich supplementary cementitious materials to partially replace Portland cement is a well-established empirical approach to mitigate expansion of concrete caused by alkali-silica reaction (ASR). However, the mechanisms behind it are still not completely understood. Synthesis of ASR products in the laboratory provides a unique opportunity...
conference paper 2021
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Oesch, Tyler (author), Weise, Frank (author), Marx, Heidi (author), Kositz, Mario (author), Huenger, Klaus-Juergen (author)
Intensified Alkali-Silica Reaction (ASR) damage has occurred on German roadways in recent years, leading to requirements for compulsory pre-construction investigation of aggregate alkali sensitivity using concrete tests with external alkali supply. However, since these tests are time-consuming and cost-intensive, there is interest in replacing...
conference paper 2021
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Liu, Qing-feng (author), Mao, Li-xuan (author), Hu, Zhi (author)
Existing reinforced concrete structures experience severe durability degradation when subjected to alkali–silica reaction (ASR) and chloride attack. A special electrochemical rehabilitation treatment, containing lithium compound anolyte, has been developed to drive lithium ions into concrete as well as remove chlorides simultaneously, for...
conference paper 2021
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Takahashi, Yuya (author), Gong, Fuyuan (author), Maekawa, Koichi (author)
Using numerical simulations, this study investigated the concrete expansion damage caused by the coupled action of freeze-thaw cycles (FTC) and alkali silica reactions (ASR). In the authors’ previous experiments, it was shown that a preceding ASR definitely accelerated the succeeding expansion by FTC. Further, even if the specimens have...
conference paper 2021
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Wang, Wei (author), Zhang, Shizhe (author), Guang, Ye (author), Noguchi, Takafumi (author)
Alkali activated materials (AAMs) have received worldwide attention due to its lower embodied energy and environmental impact than that of traditional cementitious materials. However, the activators with high alkalinity may raise the risk of alkali silica reaction (ASR) induced deterioration when reactive aggregates are used, which thereby...
conference paper 2021
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Kongshaug, Simen Sørgaard (author), Larssen, Rolf Magne (author), Hendriks, M.A.N. (author), Kanstad, Terje (author), Markeset, Gro (author)
Material modelling, from the micro to the macro level, of concrete affected by alkali–silica reaction (ASR) has been devoted a lot of research. However, the application of the material models in structural analyses of reinforced concrete (RC) structures, showing the structural implications/consequences of ASR, has got little attention in the...
journal article 2021
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Zheng, X. (author), Jiang, N. (author), Zheng, Huaili (author), Wu, Yuyang (author), Heijman, Sebastiaan (author)
One framework type of high-silica zeolite only can effectively remove a limited range of organic micropollutants (OMPs) from water. In order to extend the OMP removal range, different types of high-silica zeolites need to be combined in the adsorption process. In this study, Mordernite (MOR) and ZSM-5 (MFI) high-silica zeolite powders were mixed...
journal article 2021
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Wang, Wei (author), Zhang, Shizhe (author), Ye, G. (author), Noguchi, Takafumi (author)
Alkali activated materials (AAMs) have received worldwide attention due to its lower embodied energy and environmental impact than that of traditional cementitious materials. However, the activators with high alkalinity may raise the risk of alkali silica reaction (ASR) induced deterioration when reactive aggregates are used, which thereby...
conference paper 2021
Searched for: subject%3A%22Silica%22
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