Measurement of char oxidation rate of larch Glue Laminated Timber

Kinetics have been studied of oxidation of (1-hydroxybenzyl)ferrocenes substituted in phenyl ring with bis(triphenylsilyl) chromate in benzene solutions as well as protonation of these alcohols in sulphuric acid medium. Logarithms of the oxidation rate constants (kobs, 20-40 °C) and those of the protonation equilibrium constants (KR+, 25 °C) show linear dependence on the Hammett σ constants, the ρ constant values being -0.86 to -0.40 and -2.50, respectively. These negative values suggest that the both processes are influenced by the same effects and confirm the mechanism proposed earlier for oxidation of alcohols with ferrocenyl substituent by action of bis(triphenylsilyl) chromate in aprotic solvents.

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96/04148 Laboratory studies on devolatilization and char oxidation under PFBC conditions. 2. fuel nitrogen conversion to nitrogen oxides

Fuel and Energy Abstracts ◽

10.1016/0140-6701(96)82430-1 ◽

1996 ◽

Vol 37 (4) ◽

pp. 288

Keyword(s):

Nitrogen Oxides ◽

Laboratory Studies ◽

Nitrogen Conversion ◽

Char Oxidation

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Formation of synthetic analogues of double metal-hydroxy carbonate minerals under controlled pH conditions: I. The synthesis of pyroaurite and reevesite

Clay Minerals ◽

10.1180/claymin.1990.025.2.03 ◽

1990 ◽

Vol 25 (2) ◽

pp. 161-179 ◽

Cited By ~ 22

Author(s):

H. C. B. Hansen ◽

R. M. Taylor

Keyword(s):

Oxidation Rate ◽

Reasonable Agreement ◽

Single Phase ◽

Morphological Features ◽

Air Oxidation ◽

Synthetic Analogues ◽

Synthesis Technique ◽

Homogeneous Product ◽

Ph Conditions ◽

Hydroxy Carbonate

AbstractTwo-layered Fe(III)-M(II) hydroxy carbonates (M(II) = Ni or Mg) have been synthesized by induced hydrolysis using controlled air oxidation of an aqueous Fe(II)-M(II) mixture (M(II)/Fe(II) ratio >3) at a pH below which the hydroxide of the M(II) cation precipitates. The crystalline, homogeneous product can be a single phase consisting of very thin circular to hexagonal plates (0·2–0·8 µm diam.). For synthetic reevesite (Ni(II)-Fe(III) hydroxy carbonate), stable spherular aggregates are formed. The well crystallized products have an M(II)/Fe(III) ratio of about two. However, by varying the pH, the initial M(II)-Fe(III) ratio and the oxidation rate, the M(II)/Fe(III) ratio in the product and its crystallinity can be varied. The derived formulae are in reasonable agreement with the known composition of pyroaurite-type compounds. Possible synthesis pathways are discussed. The ability to control some physical and morphological features of the products indicates that the synthesis technique could prove advantageous in the preparation of certain catalyst precursors.

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NADPH-dependent reduction of 2,6-dichlorophenol-indophenol by the phagocytic vesicles of pig polymorphonuclear leucocytes

Biochemical Journal ◽

10.1042/bj2100577 ◽

1983 ◽

Vol 210 (2) ◽

pp. 577-581 ◽

Cited By ~ 24

Author(s):

H Wakeyama ◽

K Takeshige ◽

S Minakami

Keyword(s):

Oxidation Rate ◽

Cetyltrimethylammonium Bromide ◽

Reductase Activity ◽

Tween 20 ◽

Polymorphonuclear Leucocytes ◽

Resting Cells ◽

Low Concentrations ◽

Km Value ◽

Nadph Oxidation

NADPH-dependent 2,6-dichlorophenol-indophenol (DCIP) reductase activity in the homogenate of phagocytosing pig polymorphonuclear leucocytes was twice that of the resting cells and the activity in the phagocytic vesicles corresponded to the activity increment due to phagocytosis. The apparent Km value of the reductase activity in the vesicles for NADPH was 30 microM, which is similar to that of the NADPH-dependent superoxide (O2-) formation. Increasing the DCIP reductase activity by increasing the DCIP concentration caused a decrease in the O2- –forming activity, the NADPH oxidation rate being constant and independent of the dye concentration. p-Chloromercuribenzoate and cetyltrimethylammonium bromide at low concentrations inhibited the O2- –forming activity of the vesicles without inhibiting the DCIP reductase. Quinacrine inhibited both O2- formation and DCIP reduction. The DCIP reductase activity could be extracted with a mixture of deoxycholate and Tween-20, which extracts the O2- –forming activity. The reductase activity in the extract was enhanced 2-fold by the addition of FAD, and its apparent Km was 0.085 microM. These results indicate that the NADPH-dependent DCIP reductase activity of the phagocytic vesicles is catalysed by a flavin-containing component of the O2- –forming system.

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The mitochondrial consequences of uncoupling intact cells depend on the nature of the exogenous substrate

Biochemical Journal ◽

10.1042/bj3550231 ◽

2001 ◽

Vol 355 (1) ◽

pp. 231-235 ◽

Cited By ~ 6

Author(s):

Brigitte SIBILLE ◽

Céline FILIPPI ◽

Marie-Astrid PIQUET ◽

Pascale LECLERCQ ◽

Eric FONTAINE ◽

...

Keyword(s):

Oxidation Rate ◽

Marked Decrease ◽

Electrical Potential ◽

Atp Synthesis ◽

Intact Cells ◽

Isolated Mitochondria ◽

Exogenous Substrate ◽

High Oxidation ◽

Transmembrane Electrical Potential ◽

Sustained Increase

In isolated mitochondria the consequences of oxidative phosphorylation uncoupling are well defined, whereas in intact cells various effects have been described. Uncoupling liver cells with 2,4-dinitrophenol (DNP) in the presence of dihydroxyacetone (DHA) and ethanol results in a marked decrease in mitochondrial transmembrane electrical potential (∆ψ), ATP/ADP ratios and gluconeogenesis (as an ATP-utilizing process), whereas the increased oxidation rate is limited and transient. Conversely, when DHA is associated with octanoate or proline, DNP addition results in a very large and sustained increase in oxidation rate, whereas the decreases in ∆ψ, ATP/ADP ratios and gluconeogenesis are significantly less when compared with DHA and ethanol. Hence significant energy wastage (high oxidation rate) by uncoupling is achieved only with substrates that are directly oxidized in the mitochondrial matrix. Conversely in the presence of substrates that are first oxidized in the cytosol, uncoupling results in a profound decrease in mitochondrial ∆ψ and ATP synthesis, whereas energy wastage is very limited.

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