Plasma assisted combustion: kinetic studies and new combustion technology

TMADH (trimethylamine dehydrogenase) is a complex iron-sulphur flavoprotein that forms a soluble electron-transfer complex with ETF (electron-transferring flavoprotein). The mechanism of electron transfer between TMADH and ETF has been studied using stopped-flow kinetic and mutagenesis methods, and more recently by X-ray crystallography. Potentiometric methods have also been used to identify key residues involved in the stabilization of the flavin radical semiquinone species in ETF. These studies have demonstrated a key role for 'conformational sampling' in the electron-transfer complex, facilitated by two-site contact of ETF with TMADH. Exploration of three-dimensional space in the complex allows the FAD of ETF to find conformations compatible with enhanced electronic coupling with the 4Fe-4S centre of TMADH. This mechanism of electron transfer provides for a more robust and accessible design principle for interprotein electron transfer compared with simpler models that invoke the collision of redox partners followed by electron transfer. The structure of the TMADH-ETF complex confirms the role of key residues in electron transfer and molecular assembly, originally suggested from detailed kinetic studies in wild-type and mutant complexes, and from molecular modelling.

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Kinetic studies on the interaction of Rhizopus glucoamylase with maltodextrin and maltotriose, utilizing the absorbance change near 300 nm

Carbohydrate Research ◽

10.1016/s0008-6215(00)83597-1 ◽

1978 ◽

Vol 60 (2) ◽

pp. 335-344

Author(s):

M Ohnishi

Keyword(s):

Kinetic Studies ◽

Absorbance Change

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2-methylpentane catalytic reactions on Pt(3%wt)-HNaβ-zeolite. Kinetic studies

Journal de Chimie Physique ◽

10.1051/jcp:1998167 ◽

1998 ◽

Vol 95 (3) ◽

pp. 536-560 ◽

Cited By ~ 5

Author(s):

S. Siffert ◽

F. Garin

Keyword(s):

Kinetic Studies ◽

Catalytic Reactions

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Detection method of combustion oscillation characteristics under strong noise background

Mechanics & Industry ◽

10.1051/meca/2020085 ◽

2020 ◽

Vol 21 (6) ◽

pp. 612

Author(s):

Yunkun Wei ◽

Tianhong Zhang ◽

Zhonglin Lin ◽

Qi Xie ◽

Yan Zhang

Keyword(s):

Radiation Thermometry ◽

Hydroxyl Group ◽

Interference Signal ◽

Engine Vibration ◽

Combustion Technology ◽

Lean Fuel ◽

Combustion Oscillation ◽

Aero Engines ◽

Temperature Measurement System ◽

Multispectral Radiation Thermometry

After the lean fuel premixed combustion technology is applied to aero engines, severe combustion oscillations will be cased and led to hidden safety hazards such as engine vibration, further energy waste and other problems. Therefore, it is increasingly important to actively control combustion oscillations. In this paper, a multispectral radiation thermometry (MRT) is used to analyze the hydroxyl group, which is a measurable research object in the combustion chamber of an aero engine, and to fit the functional relationship between the radiation intensity ratio and the temperature in different bands. The theoretical value of the error is <2%. At the same time, in order to solve the problem of weak detection signal and excessive interference signal, an improved frequency domain filtering method based on fast Fourier transform is designed. Besides, the FPGA platform is used to ensure the real-time performance of the temperature measurement system, and simulations and experiments are performed. An oscillating signal with an oscillation frequency of 315 Hz is obtained on the established test platform, and the error is only 1.42%.

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Tc-99m Labeled Complexes of Aldehydes and Glutamate as Cholescintigraphic Agents

Nuklearmedizin ◽

10.1055/s-0038-1624914 ◽

1975 ◽

Vol 14 (04) ◽

pp. 330-338

Author(s):

L. G. Colombetti ◽

J. S. Arnold ◽

W. E. Barnes

Keyword(s):

Nuclear Medicine ◽

Gall Bladder ◽

Rose Bengal ◽

Valence State ◽

Monosodium Glutamate ◽

Kinetic Studies ◽

Scintillation Camera ◽

Blood Clearance ◽

Lower Valence ◽

Wire Basket

SummaryTc-99m pyridoxylidene glutamate has proven to be an excellent biliary scanning agent, far superior in many respect to the commonly used 1-131 rose bengal. The preparation of the compound as previously reported by Baker et al is too time consuming and requires the use of an autoclave which is not available in most nuclear medicine departments. In our facility, we have been preparing similar compounds using several aldehydes and monosodium glutamate to make labeled complexes having the same pharmacological characteristics. The mixture of monosodium glutamate, aldehyde, and Tc-99m pertechnetate is made slightly alkaline, purged with helium, and placed in a sealed vial. The vial, which is protected by a wire basket, is then heated in a laboratory oven at 130° C for a period of 15 to 20 minutes. During this time, the technetium is reduced to a lower valence state and bound to the complex formed. Chromatographic data show that these compounds are chemically similar to that previously reported. The compounds prepared concentrate in the gall bladder of the rabbit in less than 10 minutes. Kinetic studies have been performed on dogs with a scintillation camera and small digital computer to measure rates of blood clearance, liver and gall bladder uptake, and excretion into the intestine. The aldehyde — glutamate complex promises to be a useful scanning agent for the diagnosis of biliary and hepatocellular diseases.

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