Concept

Biogenic silica

Publications associées (87)

Controlled Microsynthesis of Silica Particles in a Microfluidic Setup

Martinus Gijs, Virendra Kumar Parashar, Josias Basil Wacker

We report on a novel microsynthesis method for easy controlling the size of silica micro- and nanoparticles. Colloids are synthesized in a microfluidic chamber by layer-wise adsorption of silica to precipitated nuclei. We prepare samples of spherical parti ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2009

Balancing nutrient inputs to Lake Kivu

Alfred Johny Wüest, Beat Mueller, Martin Schmid

The primary production in meromictic Lake Kivu is sustained by external nutrient inputs and by internal loading due to upwelling caused by sub-aquatic sources. We present here the results of external loading of phosphorus (P), nitrogen (N) and silica (Si) ...

Elsevier Sci Ltd2009

Physical and biogeochemical limits to internal nutrient loading of meromictic Lake Kivu

Alfred Johny Wüest, Beat Mueller, Martin Schmid, Bernhard Wehrli

Lake Kivu is one of the large African Rift lakes situated between the Democratic Republic of the Congo and Rwanda. In its permanently stratified hypolimnion, unusually high methane concentrations have increased further in recent decades. Because methanogen ...

Amer Soc Limnology Oceanography2009

Dissolution kinetics of biogenic silica collected from the water column and sediments of three Southern California borderland basins

Janet Gordon Hering, Tian Cheng

Understanding biogenic silica (bSi) dissolution kinetics in margin environments is important in assessing the global silicon cycle, a cycle closely linked to the global carbon cycle. This understanding is also essential to answer the question of whether bS ...

2009

Natural attenuation of arsenic by sediment sorption and oxidation

Janet Gordon Hering

Arsenic sorption onto aquifer sediments was investigated in anaerobic laboratory batch and column uptake experiments and characterized by As, Fe, and Mn X-ray absorption spectroscopy (XAS) to estimate the extent and mechanism of abiotic sorption and oxidat ...

2009

Process integration aspects of the design of a gas separation system for the upgrade of crude Synthetic Natural Gas (SNG) to grid quality in a wood to methane process

François Maréchal, Martin Gassner

The present paper investigates the prospects of process integration of the biogenic production of crude synthetic natural gas (SNG) and its upgrade to grid quality. At the example of a separation by means of a membrane cascade, a holistic design approach t ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2009

Gold Nanoparticles Supported on Passivated Silica: Access to an Efficient Aerobic Epoxidation Catalyst and the Intrinsic Oxidation Activity of Gold

David Lyndon Emsley, David Benjamin Roger Antoine Gajan

Well-defined and perfectly dispersed [(square SiO)Au(1)] surface species supported on silica have been obtained via surface organometallic chemistry and transformed upon mild reduction (H(2), 300 degrees C) into small (1.8 +/- 0.6 nm) Au particles supporte ...

AMER CHEMICAL SOC2009

Stretched-exponential a-Si:H/c-Si interface recombination decay

Christophe Ballif, Stefaan De Wolf

The electronic properties of hydrogenated amorphous silicon (a-Si:H) relax following stretched exponentials. This phenomenon was explained in the past by dispersive hydrogen diffusion, or by retrapping included hydrogen motion. In this letter, the authors ...

2008

Optical properties of annealed Mn2+-doped ZnS nanoparticles

Heinrich Hofmann, Alke Fink, Benedikt Steitz, Yvonne Axmann

Cysteine stabilized ZnS and Mn2+-doped ZnS nanoparticles were synthesized by a wet chemical route. Using the ZnS:Mn2+ nanoparticles as seeds, silica-coated ZnS (ZnS@Si) and ZnS:Mn2+ (ZnS:Mn2+@Si) nanocomposites were formed in water by hydrolysis and conden ...

2008

Hierarchical assembly of the siliceous skeletal lattice of the hexactinellid sponge Euplectella aspergillum

Georg Fantner

Despite its inherent mechanical fragility, silica is widely used as a skeletal material in a great diversity of organisms ranging from diatoms and radiolaria to sponges and higher plants. In addition to their micro- and nanoscale structural regularity, man ...

2007

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