Hydrothermal degradation of β-estradiol and oxytetracycline at selective reaction severities

In an attempt to identify polysaccharide components in thin sections of D. maydis, procedures were employed such that a PAS localization could be carried out. Three different fixatives were evaluated ie. glutaraldehyde, formaldehyde and paraformaldehyde. These were used in conjunction with periodic acid (PA), thiosemicarbazide(TSC), and osmium tetroxide(Os) to localize polysaccharides in V. maydis using a pre-embedded reaction procedure. Polysaccharide localization is based on the oxidation of vic-glycol groups by PA, and the binding of TSC as a selective reaction center for the formation of osmium black. The reaction product is sufficiently electron opaque, insoluble in lipids, not altered when tissue is embedded, and has a fine amorphous character.

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Mechanistic Study on Facet-Dependent Deposition of Metal Nanoparticles on Decahedral-Shaped Anatase Titania Photocatalyst Particles

Catalysts ◽

10.3390/catal8110542 ◽

2018 ◽

Vol 8 (11) ◽

pp. 542 ◽

Cited By ~ 4

Author(s):

Kenta Kobayashi ◽

Mai Takashima ◽

Mai Takase ◽

Bunsho Ohtani

Keyword(s):

Mechanistic Study ◽

Phase Reaction ◽

Surface Charges ◽

Platinum Nanoparticle ◽

Nanoparticle Deposition ◽

Selective Reaction ◽

Anatase Titania ◽

Deposition Density ◽

Titania Photocatalyst ◽

Source Materials

Facet-selective gold or platinum-nanoparticle deposition on decahedral-shaped anatase titania particles (DAPs) exposing {001} and {101} facets via photodeposition (PD) from metal-complex sources was reexamined using DAPs prepared with gas-phase reaction of titanium (IV) chloride and oxygen by quantitatively evaluating the area deposition density on {001} and {101} and comparing with the results of deposition from colloidal metal particles in the dark (CDD) or under photoirradiation (CDL). The observed facet selectivity, more or less {101} preferable, depended mainly on pH of the reaction suspensions and was almost non-selective at low pH regardless of the deposition method, PD or CDL, and the metal-source materials. Based on the results, the present authors propose that facet selectivity is attributable to surface charges (zeta potential) depending on the kind of facets, {001} and {101}, and pH of the reaction mixture and that this concept can explain the observed facet selectivity and possibly the reported facet selectivity without taking into account facet-selective reaction of photoexcited electrons and positive holes on {101} and {001} facets, respectively.

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An extensive parameter study of hydrotropic extraction of steam-pretreated birch

Biomass Conversion and Biorefinery ◽

10.1007/s13399-021-01425-w ◽

2021 ◽

Author(s):

Johanna Olsson ◽

Michael Persson ◽

Mats Galbe ◽

Ola Wallberg ◽

Ann-Sofi Jönsson

Keyword(s):

Residence Time ◽

Steam Explosion ◽

Room Temperature ◽

Initial Step ◽

Parameter Study ◽

Hydrothermal Degradation ◽

Steam Explosion Pretreatment ◽

Lignin Extraction ◽

Extraction Step ◽

Lignin Recovery

AbstractEfficient fractionation of lignocellulosic biomass is an important step toward the replacement of fossil-based products. However, the utilisation of all of the components in biomass requires various fractionation techniques. One promising process configuration is to apply steam explosion for the recovery of hemicelluloses and a subsequent hydrotropic extraction step for the delignification of the remaining solids. In this work, the influence of residence time, temperature and biomass loading on lignin recovery from birch using sodium xylene sulphonate as a hydrotrope was investigated. Our results show that residence time, temperature and biomass loading correlate positively with lignin extraction, but the effects of these parameters were limited. Furthermore, when steam explosion was implemented as the initial step, hydrotropic extraction could be performed even at room temperature, yielding a lignin extraction of 50%. Also, hydrothermal degradation of the material was necessary for efficient delignification with sodium xylene sulphonate, regardless of whether it occurs during steam explosion pretreatment or is achieved at high temperatures during the hydrotropic extraction.

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