Experimental Estimation of the Measured Loss Power of Magnetic Nanoparticles

July 27, 2017

In clinical and biomedical applications of magnetic nanoparticle heating, the importance of accurate and precise heating rate measurements cannot be understated. There is currently no standard equipment, methodology, or reference materials to inform and validate data obtained from such measurements. Theoretical modelling relies upon data from such measurements to guide improvements and to distinguish among competing models. Yet, measurement methods vary and are often conducted under conditions that violate the underlying thermodynamic principles upon which the measurement is founded.

Robert Ivkov, Frederik Soetaert et al independently ascertained regions of data that adhere to the thermodynamic criteria, and yet even within these regions significant variability of measurement is observed. Variations within a single measurement actually exceed the variance among replicate measurements. Such variation within the measurements can be attributed to complex magnetohydrodynamic responses of the magnetic fluid and to heat transfer within the sample. Distinguishing between these effects is not possible without additional orthogonal measurements.

Check out this careful and important work for the magnetic hyperthermia community here. It was just published in the journal "Scientific Reports".

The Future of Transport is Magnetic

June 22, 2017

The idea of creating new high-speed mass transit systems is a hot topic for many scientists around the world. Spurred on by technology engineering entrepreneur, Elon Musk, the race is on to create pods that can transport passengers and cargo at high speeds. Musk, the founder and co-founder of several innovative companies including Tesla (premium electric cars), SolarCity (solar energy supply), and PayPal (online payment portal), has inaugurated the Hyperloop project with one of his companies, SpaceX. Although SpaceX was originally set up to explore aerospace manufacture and transport, with the ultimate goal of enabling colonization of other planets, Musk recognized that harnessing the expertise of aeronautical engineers could revolutionize ground transport, and so set up Hyperloop.
The Hyperloop concept is being developed so that pods will travel at very high speeds along a tube, to provide an alternative to flying, rail transportation and driving, while also being safe, convenient and kinder to the environment in not using power that is dependent on fossil fuels. There are several Hyperloop sites being established around the world, and in 2015 Musk launched a competition to encourage the best international student groups to push the boundaries of science and create their ideas of how pods could operate.
Two such top universities, Massachusetts Institute of Technology (MIT, in the US) and Delft University of Technology (TU Delft, in the Netherlands), took part in the first phase of a competition in January this year to unveil their prototype pods at a Hyperloop test track in California. Challenged with a tunnel of one mile in length and six-feet diameter, the teams had to demonstrate that their pods could safely accelerate to speeds of up to 250 mph and break to a standstill without crashing. Both teams used magnetic levitation as their method of propulsion.
For more information, click here.

On the 'Centre of Gravity' Method for Measuring the Composition of Magnetite/Maghemite Mixtures

June 14, 2017

The composition or stoichiometry of magnetite and maghemite mixtures or solid solutions is an important parameter in the physical and geological sciences, and materials science. It is also significant in biomedical science, where magnetic nanoparticles are used both in vitro and clinically, and where both ferrous and ferric iron ions are known to play active roles in the production of reactive oxygen species. However, the accurate determination of the composition/stoichiometry can be problematic, as it requires either well-crystallised samples suitable for x-ray diffraction studies, or it relies on destructive testing methods involving chemical dissolution that, depending on the nature of the sample, are often either unfeasible or inappropriate.

Quentin Pankhurst together with different other groups from Denmark and Spain recently published a thorough paper on the determination of magnetite/maghemite ratios in magnetic nanoparticles. They used Fe-57 Mössbauer spectroscopy and curve-fitted it and then extracted the so-called "centre of gravity" parameter, which is the area weighted mean isomer shift at room temperature. 

The authors focused in their paper on the application of the method to materials for which the more conventional techniques are not easily applied—such as in nanoparticles or poorly crystallised particles. It is somewhat salutary to note that the Mössbauer method may find application even in more routine assays. 

Check out the paper here.

Ferrofluid Workshop 2017 - in Dresden

June 13, 2017

The basic idea in 1997, when we started the first ferrofluid workshop in Bremen (at that time „Bremer Ferrofluidworkshop“) had been to coordinate the few groups working with ferrofluids in Germany a bit better and to induce a somewhat stronger interaction. The result of this activity had been the establishment of the first DFG priority program for this field of research – the SPP 1104. In addition a series of conferences has been established – now lasting for 20 years.

The 16th German Ferrofluid Workshop (only 16, not 20 since no workshops had been held in the years of the international ICMF conferences) stands therefore for a remarkable anniversary. 20 years with continuous development of the research field, with the establishment of a second DFG priority program and with permanently growing interest in the national research community are a clear indication that a sustainable structure has been developed.This anniversary will be celebrated this year in Dresden – where the workshop has never been held before. Therefore we invite you for the 16th German Ferrofluid Workshop from July 17 - 19, 2017 in Dresden. The usual details for the conference, the registration and all further details can be found on the website under www.magnetofluiddynamik.de/ffworkshop16th/.

Stefan Odenbach is looking forward to welcome you in Dresden mid of July!

Oxford Chemist Closing in on How a Bird's Magnetic Compass Works

June 13, 2017

Migratory birds make epic journeys of thousands of kilometers each year, navigating with the help of Earth’s magnetic field. Yet the mechanism behind the biological compass that enables them to achieve this astonishing feat remains a mystery. Peter Hore of the University of Oxford is a leading proponent of the idea that this magnetic sense depends on chemical reactions involving excited radicals produced in a protein in the birds’ retinas. Mark Peplow spoke to him about the growing body of evidence behind the hypothesis.
How do we know that birds have a magnetic sense?
Experiments in the 1960s applied magnetic fields to migratory birds in cages. They tried to get out of the cages in different directions, depending on the direction of the field. In controlled experiments, birds can detect the axis of a magnetic field to within 5 degrees, and we suspect it would be more accurate in the wild, under natural conditions.
To read the whole story, check it out here.

Project MagNaStand - Towards an ISO Standard for Magnetic Nanoparticles

June 12, 2017

Uwe Steinhoff from the PTB (Berlin, Germany) has launched a new project, called MagNaStand "Towards an ISO standard for magnetic nanoparticles". This project is a direct spin-off  from RADIOMAG activities. There will be a 1st Industrial Stakeholder Workshop taking place at the PTB in Berlin on 4 July 2017. Please have a look at the attached flyer
Registration deadline: June 30, 2017
Main objectives:
1. To develop measurement methods and techniques to ensure highly qualified scientific input into the preparation of ISO 19807
2. To summarise metrological knowledge on MNPs gained in this project according to the “Metrological Checklist” ISO/TC 229 N 673, so that further normative documents covering measurement techniques for MNPs (e.g. static magnetic susceptibility, dynamic magnetic susceptibility and specific loss power) can be prepared.
3. To ensure the take up of results from finalised and ongoing FP7 and Horizon 2020 EU research projects on MNPs, e.g., “NanoMag” and “RADIOMAG”, into the international standardisation process.
4. To ensure coordinated participation of European NMIs and stakeholders in ISO’s standardisation process on MNPs to provide highest impact and fastest development of the standard.
5. To facilitate the take up of methods and technology developed in the project by technical committees, e.g., ISO/TC 229 and end-users in biomedicine, mechanical engineering and environmental remediation sectors.

Combining Protein Fibers and Iron Nanoparticles to Fortify Foods

June 12, 2017

ETH researchers are developing a new and highly effective way of fortifying iron into food and drinks. Protein nanofibrils are formed from native whey protein. The researchers combined these nanofibrils with iron nanoparticles which can be readily absorbed by the body. The iron-coated whey protein nanofibrils can be administered either in powder or liquid form, and the new compound can be easily added to different types of food without affecting their taste or smell or color. Around 1.2 billion people worldwide suffer from iron deficiency, with women worse affected than men. The ingredients are cheap and in plentiful supply. This iron food supplement would also be a good alternative for people living in poor countries who are more prone to iron deficiency than those living in western industrialized nations.


Magnetocaloric Cooling Device Using Recycled NdFeB Magnets

June 01, 2017

Magnetocaloric devices hold the potential to satisfy the rising demand for cooling in the future. One of the challenges remaining is to reduce the high ecological footprint of the permanent magnets driving the magnetic cooling cycle. Existing devices use neodymium-iron-boron (NdFeB)-type permanent magnets, which account for more than 50% of the ecological footprint of the appliance. To overcome this hurdle, TU Darmstadt and Urban Mining Company have built the first working magnetocaloric demonstrator that uses recycled NdFeB as a magnetic field source. Coupling this with the optimization of the magnets and their geometry, it is possible to further reduce the ecological footprint. Together, these two approaches help to position magnetic cooling as a realistic and sustainable cooling technology.

See more here at TU Darmstadt's website.

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