Publications by authors named "M A Gorbunov"

Phytoplankton in the ocean account for less than 1% of the global photosynthetic biomass, but contribute about 45% of the photosynthetically fixed carbon on Earth. This amazing production/biomass ratio implies a very high photosynthetic efficiency. But, how efficiently is the absorbed light used in marine photosynthesis? The introduction of picosecond and then femtosecond lasers for kinetic measurements in mid 1970s to 90 s was a revolution in basic photosynthesis research that vastly improved our understanding of the energy conversion processes in photosynthetic reactions.

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NaFeSeO with the 4/ space group was studied in sodium-ion batteries, delivering a reversible specific capacity of more than 140 mA h g. XRD and XAS studies disclosed bifunctional redox behaviour with the prevalence of anionic electrochemical activity and a likely partial decomposition of the material, which, however, does not influence the electrochemical behaviour of the system.

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The Southern Ocean contributes substantially to the global biological carbon pump (BCP). Salps in the Southern Ocean, in particular Salpa thompsoni, are important grazers that produce large, fast-sinking fecal pellets. Here, we quantify the salp bloom impacts on microbial dynamics and the BCP, by contrasting locations differing in salp bloom presence/absence.

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NaVO (η-NaVO) has been synthesized via solid-state reaction in an evacuated sealed silica ampoule and tested as electroactive material for Na-ion batteries. According to powder X-ray diffraction, electron diffraction and atomic resolution scanning transmission electron microscopy, NaVO adopts a monoclinic structure consisting of layers of corner- and edge-sharing VO tetragonal pyramids and VO tetrahedra with Na cations positioned between the layers, and can be considered as sodium vanadium(IV,V) oxovanadate NaVO(VO). Behavior of NaVO as a positive and negative electrode in Na half-cells was investigated by galvanostatic cycling against metallic Na, synchrotron powder X-ray diffraction and electron energy loss spectroscopy.

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Article Synopsis
  • Nearly 45% of the carbon fixed through photosynthesis comes from oceanic phytoplankton, which represent less than 1% of the total photosynthetic biomass on Earth.
  • This indicates a very high efficiency in converting solar energy into chemical energy through photosynthesis, but questions remain about the actual efficiency of this process.
  • Recent advancements in ultra-sensitive instruments have enabled precise measurements of energy conversion processes in phytoplankton, helping scientists understand their responses to nutrients and climate changes over various timescales.
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