Small Angle Scattering of X-Rays

Application of nanoparticles in biofuels: an overview

Biocatalysis community has witnessed a drastic increase in the number of studies for the use of enzymes in continuously operated flow reactors. This significant interest arose from the possibility of combining the strengths of the two worlds: enhanced mass transfer and resource efficient synthesis achieved in flow chemistry at micro-scales and excellent selectivities obtained in biocatalysis. Within this review, we present very recent (from 2018 to September 2020) developments in the field of biocatalysis in continuously operated systems. Briefly, we describe the fundamentals of continuously operated reactors with a special focus on enzyme-catalyzed reactions. We devoted special attention on future perspectives in this key emerging technological area ranging from process analytical technologies to digitalization.

/pdf/the-rise-of-continuous-flow-biocatalysis-fundamentals-very-yvdsie0fcf.pdf

The rise of continuous flow biocatalysis – fundamentals, very recent developments and future perspectives

A facile and tunable approach for synthesis of pure silica nanostructures from rice husk for the removal of ciprofloxacin drug from polluted aqueous solutions

Renaissance of Stöber method for synthesis of colloidal particles: New developments and opportunities.

Synthesis of nanometric silica particles via a modified Stöber synthesis route

Correlation of pore size distribution with thermal conductivity of precipitated silica and experimental determination of the coupling effect

The thermal accommodation coefficient is a measure for the quality of thermal energy exchange between gas molecules and a solid surface. It is an important parameter to describe heat flow in rarefied gases, for example, in aerospace or vacuum technology. As special application, it plays a decisive role for the thermal transport theory in silica filled vacuum insulation panels. So far, no values have been available for the material pairings of silica and various gases. For that reason, this paper presents thermal conductivity measurements under different gas-pressure conditions for precipitated and fumed silica in combination with the following gases: helium, air, argon, carbon dioxide (CO$_{2}$), sulfur dioxide (SO$_{2}$), krypton, and sulfur hexafluoride (SF$_{6}$). Additionally, a calculation method for determining thermal accommodation coefficients from the thermal conductivity curves in combination with the pore size distribution of silica determined by mercury intrusion porosimetry is introduced. The results are compared with existing models.

Thermal accommodation in nanoporous silica for vacuum insulation panels

The immobilization of enzymes into polymer hydrogels is a versatile approach to improve their stability and utility in biotechnological and biomedical applications. However, these systems typically show limited enzyme activity, due to unfavorable pore dimensions and low enzyme accessibility. Here, 3D jet writing of water-based bioinks, which contain preloaded enzymes, is used to prepare hydrogel scaffolds with well-defined, tessellated micropores. After 3D jet writing, the scaffolds are chemically modified via photopolymerization to ensure mechanical stability. Enzyme loading and activity in the hydrogel scaffolds is fully retained over 3 d. Important structural parameters of the scaffolds such as pore size, pore geometry, and wall diameter are controlled with micrometer resolution to avoid mass-transport limitations. It is demonstrated that scaffold pore sizes between 120 µm and 1 mm can be created by 3D jet writing approaching the length scales of free diffusion in the hydrogels substrates and resulting in high levels of enzyme activity (21.2% activity relative to free enzyme). With further work, a broad range of applications for enzyme-laden hydrogel scaffolds including diagnostics and enzymatic cascade reactions is anticipated.

/pdf/enzyme-scaffolds-with-hierarchically-defined-properties-via-4g7g9zj6gd.pdf

Enzyme Scaffolds with Hierarchically Defined Properties via 3D Jet Writing.

https://publikationen.bibliothek.kit.edu/1000096145/83135308

Manuel Meier

Papers

Synthesis of nanometric silica particles via a modified Stöber synthesis route

Correlation of pore size distribution with thermal conductivity of precipitated silica and experimental determination of the coupling effect

Thermal accommodation in nanoporous silica for vacuum insulation panels

Enzyme Scaffolds with Hierarchically Defined Properties via 3D Jet Writing.

Multi-scale characterization of precipitated silica