A5018676502- Calcium Carbonate Crystallization and Inhibition
- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Air Quality and Health Impacts
- Radioactive element chemistry and processing
- Air Quality Monitoring and Forecasting
- Bone Tissue Engineering Materials
- Thermal and Kinetic Analysis
- Paleontology and Stratigraphy of Fossils
- Atmospheric and Environmental Gas Dynamics
- Advanced X-ray and CT Imaging
- X-ray Spectroscopy and Fluorescence Analysis
- Nuclear Materials and Properties
- Cephalopods and Marine Biology
- Building materials and conservation
- Groundwater flow and contamination studies
- Catalytic Processes in Materials Science
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
Paul Scherrer Institute
2016-2022
ETH Zurich
2018-2019
Swiss Light Source
2018-2019
Bioengineering (Switzerland)
2019
Institute for Biomedical Engineering
2019
The University of Sydney
2016
Mechanisms of CaCO3 nucleation from solutions that depend on multistage pathways and the existence species far more complex than simple ions or ion pairs have recently been proposed. Herein, we provide a tightly coupled theoretical experimental study precede initial stages nucleation. Starting molecular simulations, succeed in correctly predicting bulk thermodynamic quantities data, including equilibrium constants, titration curves, detailed x-ray absorption spectra taken supersaturated...
Abstract In viscous, organic-rich aerosol particles containing iron, sunlight may induce anoxic conditions that stabilize reactive oxygen species (ROS) and carbon-centered radicals (CCRs). laboratory experiments, we show mass loss, iron oxidation radical formation release from photoactive organic iron. Our results reveal a range of temperature relative humidity, including ambient conditions, control ROS build up CCR persistence in photochemically active, viscous particles. We find can attain...
Nature possesses a unique control over the formation of CaCO3 crystals that imparts fascinating mechanical properties to many CaCO3-based biomaterials. This high level is, at least in part, achieved through use certain soluble additives influence crystallization amorphous (ACC). Inspired by nature, excellent work has been performed elucidate on ACC is dispersed bulk aqueous solutions or subjected elevated temperatures. By contrast, very little known about when exposed humid environment...
Abstract. Iron(III) carboxylate photochemistry plays an important role in aerosol aging, especially the lower troposphere. These complexes can absorb light over a broad wavelength range, inducing reduction of iron(III) and oxidation ligands. In presence O2, ensuing radical chemistry leads to further decarboxylation, production .OH, HO2., peroxides, oxygenated volatile organic compounds, contributing particle mass loss. The peroxides turn reoxidize iron(II) back iron(III), closing...
A facile aerosol-based method for the synthesis of pure and stable amorphous calcium carbonate (ACC) is presented. The relies on instantaneous carbonation hydroxide aerosols with carbon dioxide followed by rapid drying freshly formed ACC. ACC display extended stability against humidity induced crystallization.
Under ambient conditions, marine organisms are able to synthesize a variety of functional materials, ranging from eye lenses protective shells through the meticulous control over magnesium incorporation into calcite during its crystallization. The mechanistic understanding how they achieve such exquisite control, at constant magnesium-to-calcium ratio and is important in development bioinspired materials. However, replication these processes laboratory still challenging. Herein, we present...
The understanding of nucleation and crystallization is fundamental in science technology. In solution, these processes are complex involving multiple transformations from ions ion pairs through amorphous intermediates to crystalline phases. X-ray absorption spectroscopy (XAS), which sensitive liquid, phases offers prospects demystifying processes. However, for low Z elements the use situ requires tender range, often limited by vacuum requirements thereby complicating measurements. To...
Abstract. Iron(III) carboxylate photochemistry plays an important role in aerosol aging, especially the lower troposphere. These complexes can absorb light over a broad wavelength range, inducing reduction of iron(III) and oxidation ligands. In presence O2, ensuing radical chemistry leads to further decarboxylation, production ·OH, HO2·, peroxides, oxygenated volatile organic compounds, contributing particle mass loss. The peroxides turn re-oxidize iron(II) back iron(III), closing...
Here we demonstrate a method for performing X-ray absorption spectroscopy (XAS) on airborne aerosols. XAS provides unique insight into elemental composition, chemical and phase state, local coordination electronic structure of both crystalline amorphous matter. The aerosol is generated from different salt solutions using commercial atomizer dried diffusion drier. Embedded in carrier gas, the guided experimental chamber analysis. Typical particle sizes range some 10 to few 100 nm. Inside...
A comparative study of ex-situ and in-operando X-ray diffraction experiments using the fast lithium ion conductor Li 0.18 Sr 0.66 Ti 0.5 Nb O 3 will be presented.Ex-situ analysis synchrotron data suggests that a single phase material exists for all discharges to as low 0.422 V.For samples with higher content, it is possible determine position from data.However, reveals kinetically driven two region on cycling below 1 V. Monitoring change in unit cell dimension during electrochemical showed...
<p>Heavy aerosol loading threatens human health across the globe and is typically related to photochemical processing associated with emission of organic, inorganic trace metal compounds. Aerosol particles dominated by organic solutes may attain a high or ultra-high viscosity (> 10<sup>12</sup> Pa s) becoming solid-like in cold dry air, limiting diffusion reactive molecules through particle volume, thus slowing chemistry. In contrast,...