Iron oxide nanoparticles of reduced oxidation state, mainly in the form of magnetite, have been synthesized utilizing a new continuous, gas-phase, nonpremixed flame method using hydrocarbon fuels. This method takes advantage of the characteristics of the inverse flame, which is produced by injection of oxidizer into a surrounding flow of fuel. Unlike traditional flame methods, this configuration allows for the iron particle formation to be maintained in a more reducing environment. The effects of flame temperature, oxygen-enrichment and fuel dilution (i.e. the stoichiometric mixture fraction), and fuel composition on particle size, Fe oxidation state, and magnetic properties are evaluated and discussed. The crystallite size, Fe(II) fraction, and saturation magnetization were all found to increase with flame temperature. Flames of methane and ethylene were used, and the use of ethylene resulted in particles containing metallic Fe(0), in addition to magnetite, while no Fe(0) was present in samples synthesized using methane.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2835527PMC
http://dx.doi.org/10.1016/j.jaerosci.2010.01.003DOI Listing

Publication Analysis

Top Keywords

oxidation state
12
iron oxide
8
oxide nanoparticles
8
nanoparticles reduced
8
reduced oxidation
8
flame temperature
8
flame
5
gas-phase flame
4
flame synthesis
4
synthesis properties
4

Similar Publications

Waterlogging is a significant stressor for crops, particularly in lowland regions where soil conditions exacerbate the problem. Waterlogged roots experience hypoxia, disrupting oxidative phosphorylation and triggering metabolic reorganization to sustain energy production. Here, we investigated the metabolic aspects that differentiate two soybean sister lines contrasting for waterlogging tolerance.

View Article and Find Full Text PDF

Cholecystokinin (CCK) is a major neuropeptide in the brain that functions as a neurotransmitter, hormone, and growth factor. The peptide and its receptors are widely expressed in the brain. CCK signaling modulates synaptic plasticity and can improve or impair memory formation, depending on the brain areas studies and the receptor subtype activated.

View Article and Find Full Text PDF

Freezing extends the shelf life of foods but often leads to structural damage due to ice crystal formation, negatively impacting quality attributes. Oscillating magnetic field (OMF)-assisted supercooling has emerged as a potential technique to overcome these limitations by inhibiting ice nucleation and maintaining foods in a supercooled state. Despite its potential, the effectiveness and underlying mechanisms of OMF-assisted supercooling remain subjects of debate.

View Article and Find Full Text PDF

Shifts of abundance and community composition of nitrifying microbes along the Changjiang Estuary to the East China Sea.

World J Microbiol Biotechnol

January 2025

Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, School of Geographical Sciences, Fujian Normal University, Fuzhou, China.

Nitrification, the oxidation of ammonium to nitrate via nitrite, links nitrogen fixation and nitrogen loss processes, playing key roles in coastal nitrogen cycle. However, few studies have simultaneously examined both ammonia-oxidizing and nitrite-oxidizing microbes. This work investigated the abundance and community structure of ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), and nitrite-oxidizing bacteria (NOB) using archaeal amoA gene, bacterial amoA gene, and NOB nxrB gene, respectively, through q-PCR and Sanger sequencing along the Changjiang Estuary salinity gradient.

View Article and Find Full Text PDF

Direct formate fuel cells (DFFCs) have received increasing attention due to their environmentally benign and highly safe characteristics. However, the absence of highly active electrocatalysts for the formate oxidation reaction (FOR) restricts their widespread application. Currently, the design of FOR catalysts, which relies on experimental trial-and-error and high-throughput DFT calculations, is costly and time-consuming.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!