Selectivity of isomeric product formation in solid state photochlorination reactions of methylcyclopentane and methylcyclohexane

Avaliou-se a capacidade de conversão de isoflavonas glicosiladas às suas formas agliconas pelo uso de β- glicosidase de Aspergillus oryzae ATCC 22786. A produção de daidzeína e genisteína foi acompanhada por 96 h de fermentação em estado sólido, usando-se farelo de soja e suspensão de esporos do fungo a 30ºC. Notou-se a conversão de glicosil-isoflavonas após 24 h e redução significativa na sua quantidade, depois de 48 h de fermentação. A atividade enzimática acompanhou a formação de produto até 72 h (0,2 UI/ mL), apresentando leve diminuição em 96 h (0,19 UI/ mL). Após 48 h obteve-se conversão total de daidzina e genistina, com formação de 551,1 e 17,2 µg/g de daidzeína e genisteína, respectivamente. A produção de genisteína, no entanto, mostrou-se significativamente superior em 24 h de fermentação (289,3 µg/g). Concluiuse que a β-glicosidase produzida por Aspergillus oryzae ATCC 22786 foi capaz de converter glicosilisoflavonas em agliconas por fermentação em estado sólido a 30ºC. CONVERSION OF SOY DAIDZEIN AND GENISTEIN BY β -GLUCOSIDASE OF Aspergillus oryzae Abstract The conversion capacity of glucoside isoflavones to aglycones by Aspergillus oryzae ATCC 2786 β-glucosidase was evaluated. The production of daidzein and genistein was observed for 96 h in solid state fermentation, by utilizing soy flour and a suspension of fungal spores at 30ºC. The conversion of glucoside isoflavones was noted after 24 h and a significant reduction in its quantity after 48 h of fermentation. The enzymatic activity followed the product formation until 72 h (0.2 UI/mL), showing a slight reduction in 96 h (0.19 UI/mL). After 48 h total conversion of daidzein and genistein was obtained, with formation of 551.1 and 17.2 µg/g of daidzein and genistein, respectively. The production of genistein, however, was significantly higher in 24 h of fermentation (289.3 µg/g). It was concluded that the produced β-glucosidase by Aspergillus oryzae was capable to convert glucoside isoflavones in to aglycones by solid state fermentation at 30ºC.

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Emission solvatochromic, solid-state and aggregation-induced emissive α-pyrones and emission-tuneable 1H-pyridines by Michael addition–cyclocondensation sequences

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.262 ◽

2019 ◽

Vol 15 ◽

pp. 2684-2703 ◽

Cited By ~ 1

Author(s):

Natascha Breuer ◽

Irina Gruber ◽

Christoph Janiak ◽

Thomas J J Müller

Keyword(s):

Solid State ◽

Michael Addition ◽

Photophysical Properties ◽

Ethyl Cyanoacetate ◽

Product Formation ◽

Quantum Yields ◽

Substitution Pattern ◽

Fluorescence Quantum Yields ◽

Emission Enhancement ◽

Donor Acceptor

Starting from substituted alkynones, α-pyrones and/or 1H-pyridines were generated in a Michael addition–cyclocondensation with ethyl cyanoacetate. The peculiar product formation depends on the reaction conditions as well as on the electronic substitution pattern of the alkynone. While electron-donating groups furnish α-pyrones as main products, electron-withdrawing groups predominantly give the corresponding 1H-pyridines. Both heterocycle classes fluoresce in solution and in the solid state. In particular, dimethylamino-substituted α-pyrones, as donor–acceptor systems, display remarkable photophysical properties, such as strongly red-shifted absorption and emission maxima with daylight fluorescence and fluorescence quantum yields up to 99% in solution and around 11% in the solid state, as well as pronounced emission solvatochromism. Also a donor-substituted α-pyrone shows pronounced aggregation-induced emission enhancement.

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Kinetics of accelerated solid-state fermentation of organic-rich municipal solid waste

Water Science & Technology ◽

10.2166/wst.2000.0076 ◽

2000 ◽

Vol 41 (3) ◽

pp. 231-238 ◽

Cited By ~ 19

Author(s):

E.R. Viéitez ◽

J. Mosquera ◽

S. Ghosh

Keyword(s):

Solid State ◽

Solid State Fermentation ◽

Anaerobic Fermentation ◽

Landfill Gas ◽

Product Formation ◽

Hydrolysis Rate ◽

Methane Formation ◽

Effluent Recirculation ◽

Rapid Hydrolysis ◽

Biphasic Process

Biotransformation of landfill solid wastes is a slow process requiring decades for completion. Accelerated anaerobic fermentation in modulated landfill environments may alleviate or eliminate pollution of land, water and air. This research was undertaken to demonstrate the application of biphasic fermentation to a simulated laboratory-scale landfill to effect rapid biomethanation of biodegradable solids. The biphasic process consisted of solid-state, acidogenic fermentation of the organic fraction of MSW followed by biomethanation of acidic hydrolysates in a separate methane fermenter. Solid-state fermentation of the MSW with effluent recirculation resulted in rapid hydrolysis, acidification and denitrification, with soluble COD and VFA concentrations accumulating to inhibitory levels of 60,000 mg/l and 13,000 mg/l, respectively, at a pH of 4.5. The landfill gas methane concentration reached a maximum of 55 mol.%. By comparison, the methanogenic reactor produced high methane-content (70–85 mol.%) gases. The biphasic process effected carbohydrate, lipid, and protein conversion efficiencies of 90%, 49%, and 37%, respectively. Development of a Monod-type product-formation model was undertaken to predict methane formation and to determine kinetic parameters for the methanogenic processes in the simulated landfill and separate methane reactors. A first-order solids hydrolysis rate constant of 0.017 day−1 was evaluated to show that landfill solids hydrolysis was slower than the inhibited methanogenesis rate.

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Investigation of the Reaction between Fe2O3 and Al Accomplished by Ball Milling and Self-Propagating High-Temperature Techniques

Zeitschrift für Naturforschung A ◽

10.1515/zna-1997-6-713 ◽

1997 ◽

Vol 52 (6-7) ◽

pp. 539-549 ◽

Cited By ~ 8

Author(s):

Giacomo Cao ◽

Giorgio Concas ◽

Anna Corrias ◽

Roberto Orru' ◽

Giorgio Paschina ◽

...

Keyword(s):

High Temperature ◽

Solid State ◽

Ball Milling ◽

Reaction Mechanisms ◽

Product Formation ◽

Solid State Reactions ◽

X Ray Diffraction ◽

X Ray ◽

Air Atmosphere ◽

Aluminothermic Reaction

Abstract In this work we investigate the mechanism of product formation of the aluminothermic reaction of Fe2O3 in the presence of Al2O3 using Ball Milling and Self-propagating High-temperature techniques. Results obtained by experiments under either argon or air atmosphere are analysed by X-ray diffraction and Mössbauer spectroscopy, together with microstructure observations. It is shown that ball milling products are strongly affected by the kind of atmosphere, while self-propagating high-temperature ones are only weakly influenced. Reaction mechanisms taking place in these cases are proposed. While ball milling involves only solid state reactions, the formation of a melt occurs under self-propagating high-temperature conditions.

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Crystallizing Vanadium Pentoxide Nanostructures in the Solid-State Using Modified Block Copolymer and Chitosan Complexes

Journal of Nanomaterials ◽

10.1155/2015/105157 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 6

Author(s):

C. Diaz ◽

G. Barrera ◽

M. Segovia ◽

M. L. Valenzuela ◽

M. Osiak ◽

...

Keyword(s):

Solid State ◽

Preparation Method ◽

Product Formation ◽

Polymeric Chain ◽

Calcination Process ◽

Molar Ratios ◽

Light Region ◽

Modified Block ◽

Metal Polymer ◽

Coordination Reaction

A systematic study of the synthesis of V2O5nanostructured materials using macromolecular PS-co-4-PVP·(VCl3)yand chitosan·(VCl3)ycomplexes is presented. It is demonstrated that various coordination degrees of the metal into the polymeric chain specifically influence the product formation after pyrolysis. PS-co-4-PVP·(VCl3)yand chitosan·(VCl3)ycomplexes were prepared by simple coordination reaction of VCl3with the respective polymer in molar ratios 1 : 1, 1 : 5, and 1 : 10 metal/polymer and characterized by elemental analysis, IR spectroscopy, and TGA/DSC analysis. Solid-state thermolysis of these precursors at several temperatures under air results in nanostructured V2O5using all precursors. The size and shape of the nanostructured V2O5depend on the nature of the polymer. For the chitosan·(VCl3)yprecursors sub-10 nm nanocrystals are formed. The calcination process, involved in the preparation method, produces V2O5with photoluminescence in the visible light region, suggesting the possible application in oxygen sensing devices.

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Electrocatalysts derived from copper complexes transform CO into C2+ products effectively in a flow cell

10.21203/rs.3.rs-83176/v2 ◽

2021 ◽

Author(s):

Shaoxuan Ren ◽

Zishuai Zhang ◽

Eric Lees ◽

Arthur Fink ◽

Luke Melo ◽

...

Keyword(s):

Solid State ◽

Copper Complexes ◽

Copper Phthalocyanine ◽

Product Formation ◽

Flow Cell ◽

Reduction Reaction ◽

Flow Cells ◽

New Class ◽

Current Densities ◽

Performance Flow

Abstract The highest performance flow cells capable of electrolytically converting CO2 into higher value chemicals and fuels pass a concentrated hydroxide electrolyte across the cathode. A major problem for CO2 electrolysis is that this strongly alkaline medium converts the majority of CO2 into unreactive HCO3– and CO32– rather than CO2 reduction reaction (CO2RR) products. The electrolysis of CO (instead of CO2) does not suffer from this same problem because CO does not react with hydroxide. Moreover, CO can be more readily converted into products containing two or more carbon atoms (i.e., C2+ products). While several solid-state electrocatalysts have proven competent at converting CO into C2+ products, we demonstrate here that molecular electrocatalysts are also effective at mediating this transformation in a flow cell. Using a molecular copper phthalocyanine (CuPc) electrocatalyst, CO was electrolyzed into C2+ products at high rates of product formation (i.e., current densities J ≥200 mA/cm2), and at high Faradaic efficiencies for C2+ production (FEC2+; 72% at 200 mA/cm2). These findings present a new class of electrocatalysts for making carbon-neutral chemicals and fuels.

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Isomeric product distributions from solid-state chain reactions and low-temperature microexplosions of acetylene and chlorine

The Journal of Physical Chemistry ◽

10.1021/j100192a042 ◽

1992 ◽

Vol 96 (13) ◽

pp. 5411-5414 ◽

Cited By ~ 1

Author(s):

Mikhail A. Ovchinnikov ◽

Charles A. Wight

Keyword(s):

Solid State ◽

Low Temperature ◽

Chain Reactions ◽

Product Distributions ◽

Isomeric Product

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Preparation of Thin Cadmium Telluride Samples for Electron Microscope Studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052754 ◽

1974 ◽

Vol 32 ◽

pp. 548-549

Author(s):

T. J. Magee ◽

J. Peng ◽

J. Bean

Keyword(s):

Electron Microscope ◽

Sulfuric Acid ◽

Solid State ◽

Sample Preparation ◽

Cadmium Telluride ◽

Potassium Dichromate ◽

Optical Components ◽

The Past ◽

Solid State Devices

Cadmium telluride has become increasingly important in a number of technological applications, particularly in the area of laser-optical components and solid state devices, Microstructural characterizations of the material have in the past been somewhat limited because of the lack of suitable sample preparation and thinning techniques. Utilizing a modified jet thinning apparatus and a potassium dichromate-sulfuric acid thinning solution, a procedure has now been developed for obtaining thin contamination-free samples for TEM examination.

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