Concept

Calcium

Publications associées (27)

Nanoscale thermal control of a single living cell enabled by diamond heater-thermometer

We report a new approach to controllable thermal stimulation of a single living cell and its compartments. The technique is based on the use of a single polycrystalline diamond particle containing silicon-vacancy (SiV) color centers. Due to the presence of ...

Nature Portfolio2023

Atomic-Level and Surface Structure of Calcium Silicate Hydrate Nanofoils

Karen Scrivener, Paul Bowen, Ziga Casar, Aslam Kunhi Mohamed

Deciphering the calcium silicate hydrate (C-S-H) surface is crucial for unraveling the mechanisms of cement hydration and property development. Experimental observations of C-S-H in cement systems suggest a surface termination which is fundamentally differ ...

AMER CHEMICAL SOC2023

Cholesterol-Containing Liposomes Decorated With Au Nanoparticles as Minimal Tunable Fusion Machinery

Francesco Stellacci, Paulo Henrique Jacob Silva

Membrane fusion is essential for the basal functionality of eukaryotic cells. In physiological conditions, fusion events are regulated by a wide range of specialized proteins, operating with finely tuned local lipid composition and ionic environment. Fusog ...

WILEY-V C H VERLAG GMBH2023

Structure analysis of beta dicalcium silicate via scanning transmission electron microscope (STEM)

Franco Alberto Zunino Sommariva, Qiao Wang

Beta-dicalcium silicate (beta-C2S), one of the main phases in Portland cement clinker, offers some promising overviews regarding CO2 and energy savings potential compared to alite. Understanding the crystalline structure and reactive sites on beta-C2S surf ...

ELSEVIER SCI LTD2022

Competing Effects of Hydration and Cation Complexation in Single-Chain Alginate

Zezhong Li

Alginic acid, a naturally occurring anionic polyelectrolyte, forms strong physically cross-linked hydrogels in the presence of metal cations. The latter engage in electrostatic interactions that compete with intra- and intermolecular hydrogen bonds, determ ...

American Chemical Society2022

A method for the reliable and reproducible precipitation of phase pure high Ca/Si ratio (>1.5) synthetic calcium silicate hydrates (C-S-H)

Karen Scrivener, Paul Bowen, Maya Nicole Harris

Various methods have been developed to synthesize C-S-H; however, these methods have only allowed for the successful production of pure-phase C-S-H with Ca:Si of 1.5 or less. Attempts to form higher Ca:Si ratios by these methods gives C-S-H (Ca:Si 1.5 or l ...

Pergamon-Elsevier Science Ltd2022

Iron incorporation in synthetic precipitated calcium silicate hydrates

David Lyndon Emsley, Paul Bowen, Brennan James Walder, Jirawan Siramanont

Effect of Fe3+ on the precipitation of synthetic calcium silicate hydrates (C-S-H) under controlled conditions has been evaluated. Using extremely basic either initial calcium nitrate or sodium silicate solutions (pH > 11), incipient formation of ferrihydr ...

Pergamon-Elsevier Science Ltd2021

Hardware and Software Interfaces Design for Multi-Panel Electrochemical Sensors

Mandresy Ivan Ny Hanitra

The exponential growth of wearable healthcare devices market is fostered by the internetof- things (IoT) era. Connected smart biosensors enable a decentralized healthcare that does not constrain the user to be in a medical facility to get a real-time insig ...

EPFL2021

Revisiting Cation Complexation and Hydrogen Bonding of Single-Chain Polyguluronate Alginate

Zezhong Li

Modifying the properties of bio-based materials has garnered increasing interest in recent years. In related applications, the ability of alginates to complex with metal ions has been shown to be effective in liquid-to-gel transitions, useful in the develo ...

American Chemical Society2021

Size-resolved aerosol pH over Europe during summer

Athanasios Nenes

The dependence of aerosol acidity on particle size, location, and altitude over Europe during a summertime period is investigated using the hybrid version of aerosol dynamics in the chemical transport model PMCAMx. The pH changes more with particle size in ...

Copernicus GmbH2021

Young's modulus and creep of calcium-silicate-hydrate compacts measured by microindentation

Karen Scrivener, Zhangli Hu

In this paper, compacts of synthetic calcium silicate hydrate (C-S-H) with 0.8-1.5 calcium-to-silicon ratio (Ca/Si) and 30-80% porosity were prepared by one-direction cold pressing. The Young's modulus and the creep of C-S-H compacts were measured by micro ...

Pergamon-Elsevier Science Ltd2020

Catechol Containing Polyelectrolyte Complex Nanoparticles as Local Drug Delivery System for Bortezomib at Bone Substitute Materials

Martin Guillermo Mueller, Jeremy Pak Hei Wong

The proteasome inhibitor bortezomib (BZM) is one of the most potent anti-cancer drugs in the therapy of multiple myeloma. In this study, an adhesive drug delivery system (DDS) for BZM was developed. Therefore, we extended the present DDS concept of polyele ...

2020

The effect of sodium hydroxide on Al uptake by calcium silicate hydrates (C S H)

Christian Ludwig, Sonya Barzgar

To reduce the CO2 emissions from cement production, Portland cement (PC) is partially replaced by supplementary cementitious materials (SCM). Reactions of SCM with PC during hydration leads to the formation of CSH with more silicon and aluminum than in PC, ...

2020

Extent of N-terminus exposure of monomeric alpha-synuclein determines its aggregation propensity

Hilal Lashuel, Anass Chiki

As an intrinsically disordered protein, monomeric alpha-synuclein (aSyn) occupies a large conformational space. Certain conformations lead to aggregation prone and non-aggregation prone intermediates, but identifying these within the dynamic ensemble of mo ...

Nature Research2020

Design of Ductile Rare-Earth-Free Magnesium Alloys

William Curtin, Binglun Yin, Rasool Ahmad

Pure Mg has low ductility due to a transition of < c+a > pyramidal dislocations to a sessile basal-oriented structure. Dilute alloying generally improves ductility. Enhancement of pyramidal cross-slip from the lower-energy pyramidal II plane to the higher- ...

SPRINGER INTERNATIONAL PUBLISHING AG2020

In Situ Liquid SAXS Studies on the Early Stage of Calcium Carbonate Formation

Andrea Testino, Agnese Carino, Mohammad Reza Andalibi

Calcium carbonate is a model system to investigate the mechanism of solid formation by precipitation from solutions, and it is often considered in the debated classical and nonclassical nucleation mechanism. Despite the great scientific relevance of calciu ...

2019

Tuning the Incorporation of Magnesium into Calcite during Its Crystallization from Additive-Free Aqueous Solution

Esther Amstad, Huachuan Du

Under ambient conditions, marine organisms are able to synthesize a variety of functional materials, ranging from eye lenses to protective shells through the meticulous control over magnesium incorporation into calcite during its crystallization. The mecha ...

AMER CHEMICAL SOC2019

Effect of Ions and Admixtures on the Growth of Synthetic Calcium Silicate Hydrate (C-S-H)

Jirawan Siramanont

This thesis investigates the effect of different parameters such as Fe (III), D-gluconate and heterogeneous particles on the nucleation and growth of synthetic C-S-H by using the dropwise precipitation method. Firstly, the effect of Fe (III) on the synthet ...

EPFL2018

Calcium phosphate formation on titanium-based surfaces: bioactivity evaluated by in vitro methods

Weitian Zhao

The prediction of implant behaviors in vivo by the use of easy-to-perform in vitro methods is of great interest in biomaterials research. In the field of bone implants, it is commonly accepted that a spontaneous formation of a hydroxyapatite (HA) layer on ...

EPFL2018

Reactivity and Performance of Limestone Calcined-Clay Cement (LC3) Cured at Low Temperature

Karen Scrivener, Franco Alberto Zunino Sommariva

Limestone calcined-clay cements (LC3) take advantage of the synergetic effects of calcium carbonate reaction with the additional aluminium provided by the calcined clay. As temperature decreases, calcium carbonate solubility increase, therefore, the early- ...

SPRINGER2018