The micronutrient iron (Fe) is recognized as a key factor in controlling oceanic primary productivity, and subsequently impacting the carbon cycle and marine ecosystem. The high-latitude area of the North Pacific is one of the three main high-nutrient and low-chlorophyll (HNLC) regions on Earth. Also, the growth of phytoplankton is limited by the availability of Fe. Climate change, human activities and ocean acidification are expected to influence the availability and transport of Fe in the ocean. Therefore, it is of great importance to study the Fe cycle and make reliable predictions for the future.
"As a result of human activity, the amount and composition of Fe induced by atmospheric decomposition has changed and affected the ocean. After depositing into the ocean, the distribution and transport of Fe is mainly determined by physical processes, e.g., mixing and upwelling.
So, clarifying the sources and transport of biologically available Fe are key scientific questions for understanding the marine ecosystem," explains Dr. Fei Chai, a researcher at the Second Institute of Oceanography and corresponding author of a project report recently published in Atmospheric and Oceanic Science Letters.
"The biological availability of Fe in the ocean also depends on the amount and strength of organic complex ligands. The spatial distribution of Fe-binding ligands is highly variable, with more ligands found in the Northwest Pacific than Northeast Pacific.
Also, the strength of ligands is mainly affected by the pH of water, with lower pH reducing the strength of ligands and decreasing the Fe uptake rate of diatoms. Therefore, under the influence of ocean acidification, the distribution and strength of Fe-binding ligands will change considerably, with subsequent impacts on the ecosystem of the North Pacific," adds Dr. Chai.
Dr. Fei Chai and his team, from the Second Institute of Oceanography, will develop and utilize a coupled physical-biological-Fe model, named ROMS-CoSiNE-Fe, in the North Pacific.
The model will incorporate the Fe cycle for the upper North Pacific and make predictions of primary production and marine ecosystems in the future. The project is funded by the National Natural Science Foundation of China from 2018 to 2022.
"These studies will explore the sources and transport of biologically available Fe in the HNLC region. The results can give scientific advice to stakeholders on the feasibility of conducting ocean Fe fertilization," says Dr. Chai, "In the future, we hope to better understand the rate of Fe uptake by phytoplankton and make predictions of changes in the marine ecosystem of the North Pacific."
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Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.
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Process engineers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have developed a method which allows the size and shape of nanoparticles in dispersions to be determined considerably quicker than ever before. Based on gold nanorods, they demonstrated how length and diameter distributions can be measured accurately in just one step instead of the complicated series of electron microscopic images which have been needed up until now. Nanoparticles from precious metals are used, for example, as catalysts and contrast agents for diagnosing cancer. The results have been published in the renowned journal Nature Communications (doi: 10.1038/s41467-018-07366-9).
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The experiments conducted from July until November at the Wendelstein 7-X fusion device at the Max Planck Institute for Plasma Physics (IPP) in Greifswald have achieved higher values for the density and the energy content of the plasma and long discharge times of up to 100 seconds – record results for devices of the stellarator type. Meanwhile, the next round of the step-by-step upgrading of Wendelstein 7-X has begun. It is to equip the device for greater heating power and longer discharges. Wendelstein 7-X, the world’s largest fusion device of the stellarator type, is to investigate the suitability of this configuration for use in a power plant.
During the course of the step-by-step upgrading of Wendelstein 7-X, the plasma vessel was fitted with inner cladding since September of last year.
Advances in environmental technology: You don’t need complex filters and laser systems to destroy persistent pollutants in water. Chemists at Martin Luther University Halle-Wittenberg (MLU) have developed a new process that works using mere sunlight. The process is so simple that it can even be conducted outdoors under the most basic conditions. The chemists present their research in the journal “Chemistry - a European Journal”.
The chemists at MLU rely on electrons moving freely in water, so-called hydrated electrons, to degrade dissolved pollutants.
The experimental investigation of ultracold quantum matter makes it possible to study quantum mechanical phenomena that are otherwise hardly accessible. A team led by the Innsbruck physicist Francesca Ferlaino has now succeeded for the first time in mixing quantum gases of the strongly magnetic elements Erbium and Dysprosium and creating a dipolar quantum mixture.
Only a few years ago it seemed unfeasible to extend the techniques of atom manipulation and deep cooling in the ultracold regime to many-valence-electron...
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