Magnetoreception and iron biomineralization in honeybees (Apis mellifera) have been investigated for several decades. Numerous open questions are still been hotly debated, especially the location of superparamagnetic magnetite. To solve this argument, we use the size-density purification technique to purify the iron granules of trophocytes and determined their magnetic properties, which include...

Changes in the inherent solid phase and aqueous interfacial properties of magnetite nanoparticles in a Massart type magnetic fluid were investigated. Magnetite nanoparticles were synthesized, purified, dialyzed against 0.001 mol dm–3 HCl and then stored at 4 °C for 6 years. The solid phase transformation of magnetite to maghemite and formation of akageneite shell on the magnetic core, as well a...

Magnetite nanoparticles (Fe₃O₄) represent the most promising materials in medical applications. To favor high-drug or enzyme loading on the nanoparticles, they are incorporated into mesoporous materials to form a hybrid support with the consequent reduction of magnetization saturation. The direct synthesis of mesoporous structures appears to be of interest. To this end, magnetite nanoparticles ...

Electron transfer from zerovalent iron (Fe0) to targeted contaminants is affected by initial Fe0 composition, the oxides formed during corrosion, and surrounding electrolytes. We previously observed enhanced metolachlor destruction by Fe0 when iron or aluminum salts were present in the aqueous matrix and Eh/pH conditions favored formation of green rusts. To understand these enhanced destruction...

Magnetospirillum gryphiswaldense and related magnetotactic bacteria form magnetosomes, which are membrane-enclosed organelles containing crystals of magnetite (Fe3O4) that cause the cells to orient in magnetic fields. The characteristic sizes, morphologies, and patterns of alignment of magnetite crystals are controlled by vesicles formed of the magnetosome membrane (MM), which contains a number...

The gravity sedimentation of three narrow-sized fractions of suspensions of magnetite particles exposed to magnetic fields ranging from 0 to 180 x 10 -4 T was studied experimentally. At volumetric solids concentrations in excess of 15%, the magnetized suspensions of magnetite with size fractions ranging from -75 to +38 μm settled more slowly than the non-magnetized suspensions. However, owing t...

These theses contains realization of a typical technological beneficiation complex for automation of control processes (in the context of beneficiation of iron ore magnetite quartzites). The hierarchy scheme of intelligence control system for such complex combining principles of neurocontrol, classification and optimal control has been shown. Results of computer modeling of classification optim...

In this study, the interaction of DMSA-coated magnetite nanoparticles (5 and 10 nm core-size) with Saccharomyces cerevisae was investigated using magnetic resonance (MR) and transmission electron microscopy (TEM). The TEM micrographs revealed magnetite nanoparticles attached externally to the cell wall. The MR data support the strong interaction among the nanoparticles supported by the cells. A...

Magnetite nanoparticles possess several properties that can make them useful for targeted delivery of radiation to tumors for the purpose of brachytherapy. Such particles are biodegradable and magnetic and can emit secondary radiation when irradiated by an external source. In this work, the dose distribution around a magnetite particle of 10 nm diameter being irradiated by monochromatic X-rays ...

Upon release of engineered nanoparticles (NPs) into the subsurface environment, their fate and transport and hence their potential environmental and public health impacts will largely depend on how stable these NPs are as suspended particles in the natural environment. In this study, we systematically examine the effect of humic acid (HA) on surface charge status and aggregation potential of ma...