New insights into globoids of protein storage vacuoles in wheat aleurone using synchrotron soft X-ray microscopy

Mature developed seeds are physiologically and biochemically committed to store nutrients, principally as starch, protein, oils, and minerals. The composition and distribution of elements inside the aleurone cell layer reflect their biogenesis, structural characteristics, and physiological functions. It is therefore of primary importance to understand the mechanisms underlying metal ion accumulation, distribution, storage, and bioavailability in aleurone subcellular organelles for seed fortification purposes. Synchrotron radiation soft X-ray full-field imaging mode (FFIM) and low-energy X-ray fluorescence (LEXRF) spectromicroscopy were applied to characterize major structural features and the subcellular distribution of physiologically important elements (Zn, Fe, Na, Mg, Al, Si, and P). These direct imaging methods reveal the accumulation patterns between the apoplast and symplast, and highlight the importance of globoids with phytic acid mineral salts and walls as preferential storage structures. C, N, and O chemical topographies are directly linked to the structural backbone of plant substructures. Zn, Fe, Na, Mg, Al, and P were linked to globoid structures within protein storage vacuoles with variable levels of co-localization. Si distribution was atypical, being contained in the aleurone apoplast and symplast, supporting a physiological role for Si in addition to its structural function. These results reveal that the immobilization of metals within the observed endomembrane structures presents a structural and functional barrier and affects bioavailability. The combination of high spatial and chemical X-ray microscopy techniques highlights how in situ analysis can yield new insights into the complexity of the wheat aleurone layer, whose precise biochemical composition, morphology, and structural characteristics are still not unequivocally resolved

Plasma–liquid interactions: a review and roadmap

Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on non-equilibrium plasmas

SiC Fabrication by carbothermal reduction of sepiolite

In this paper, the possibility of using sepiolite as Si precursor for low temperature synthesis of silicon carbide (SiC) via carbothermal-reduction reactions was studied. A sepiolite of Serbian origin and carbon (precursor-saccharose) as reducing agent were used. The green bodies with C/SiO2 = 7 ratio were carbonised at 1073K and heat-treated at 1673K (controlled Ar flow atmosphere). Phase evolution, phase content and weight loss were followed as a function of temperature and chemical activation processes of sepiolite. Starting materials and products have been characterized by means of XRD and SEM (EDS) investigations. The results show that sepiolite can be very effective source for obtaining of silicon carbide powders.5th International Conference on New Research Trends in Materials Science, Sep, 2007, Sibiu, Romani

SiC Fabrication by carbothermal reduction of sepiolite

In this paper, the possibility of using sepiolite as Si precursor for low temperature synthesis of silicon carbide (SiC) via carbothermal-reduction reactions was studied. A sepiolite of Serbian origin and carbon (precursor-saccharose) as reducing agent were used. The green bodies with C/SiO2 = 7 ratio were carbonised at 1073K and heat-treated at 1673K (controlled Ar flow atmosphere). Phase evolution, phase content and weight loss were followed as a function of temperature and chemical activation processes of sepiolite. Starting materials and products have been characterized by means of XRD and SEM (EDS) investigations. The results show that sepiolite can be very effective source for obtaining of silicon carbide powders.5th International Conference on New Research Trends in Materials Science, Sep, 2007, Sibiu, Romani