98/00533 Comparison of different mechanisms for the product formation in the simulation of coal pyrolysis

1998 ◽  
Vol 39 (1) ◽  
pp. 45
Keyword(s):  
Product Formation ◽  
Coal Pyrolysis

scholarly journals A Review on Botswana Coal Potential from a Pyrolysis and Gasification Perspective

2020 ◽  
Vol 65 (1) ◽  
pp. 80-96
Author(s):  
Mmoloki Makoba ◽  
Daniel Erich Botha ◽  
Mpho Thabang Rapoo ◽  
László Zsolt Szabó ◽  
Thapelo Shomana ◽  
...  
Keyword(s):  
Product Formation ◽  
Full Potential ◽  
Coal Pyrolysis ◽  
X Ray Diffraction ◽  
Product Selection ◽  
Complex Processes ◽  
Coal Characterization ◽  
History Of ◽  
Mass And Heat Transfer ◽  
Coal Reserves

Coal pyrolysis and gasification are promising options for the future of Botswana as the country has large coal reserves with severe limitations in terms of export options. Coal characterization facilities will be required in order to harness its full potential and methods such as proximate, ultimate and chemical structure analysis (FTIR, Raman spectroscopy and X-ray diffraction techniques) were investigated. The paper presents a brief history of pyrolysis and gasification, typical types of the reactors as well as factors that influence product selection for Botswana coal. Coal pyrolysis and gasification are complex processes and it is difficult to define the mechanisms of product formation. However, there are several kinetic models that are relevant to the sub-bituminous coal of Botswana which were proposed by researchers to describe the formation of the compounds and mathematical models that were validated by other researchers on mass and heat transfer as also presented herein.

Amidolytic Detection of Prothrombin Activation Products after SDS-Gel Electrophoresis

1989 ◽  
Vol 61 (03) ◽  
pp. 386-391 ◽  
Author(s):  
Guido Tans ◽  
Truus Janssen-Claessen ◽  
Jan Rosing
Keyword(s):  
Gel Electrophoresis ◽  
Activated Protein C ◽  
Factor Xa ◽  
Coagulation Factors ◽  
Product Formation ◽  
Chromogenic Substrate ◽  
Nitrocellulose Membrane ◽  
Activation Products ◽  
Factor Xia ◽  
Prothrombin Activation

SummaryIn this paper we report a method via which enzymatically active products formed during prothrombin activation can be detected by simple photographic means after SDS-gel electrophoresis, blotting onto a nitrocellulose membrane and visualization with the chromogenic substrate, S2238. After amidolytic detection the same nitrocellulose membrane can also be used for immunologic detection of prothrombin activation products, thus allowing a complete description of product formation during prothrombin activation.The detection limit of the so-called “amidoblot” is approximately 3 ng thrombin per gel sample which is comparable to the sensitivity of immunoblotting.It is further shown that the amidoblot technique can also be applied to other coagulation factors for which a suitable chromogenic substrate is available (factor XIIa, kallikrein, factor XIa, factor Xa, plasmin and activated protein C).

THE INFLUENCE OF ETHANOL ON THE CONVERSION OF PREGNENOLONE TO PROGESTERONE BY HUMAN PLACENTAL MICROSOMES

1974 ◽  
Vol 76 (1) ◽  
pp. 178-188 ◽  
Author(s):  
H. Lübbert ◽  
K. Pollow ◽  
R. Wagner ◽  
J. Hammerstein
Keyword(s):  
Kinetic Parameters ◽  
Enzyme Preparation ◽  
Ethanol Concentration ◽  
Hydroxysteroid Dehydrogenase ◽  
Product Formation ◽  
Linear Increase ◽  
Maximal Velocity ◽  
Microsomal Enzyme ◽  
Temperature Optima ◽  
Substrate Concentrations

ABSTRACT The effects of ethanol on kinetic parameters of placental Δ5-3β-hydroxysteroid dehydrogenase were studied. In the presence of high pregnenolone concentrations (50 μm, [S] > Km) the microsomal enzyme preparation exhibited an almost linear increase in activity as the ethanol concentration in the medium was raised from 2.5 to 15 % (v/v). At lower substrate concentrations ([S] << Km) ethanol caused inhibition. Other effects of ethanol were: linearity of product formation with time was prolonged; the maximal velocity was markedly increased; the Km for pregnenolone slightly decreased with increasing ethanol concentrations (2.5 to 10 %, v/v) whereas the Km for NAD remained the same. The pH and temperature optima of the reaction were unaffected by ethanol. Other organic solvents caused similar effects.

Phosphino-Triazole Ligands for Palladium-Catalysed Cross-Coupling

2018 ◽  
Author(s):  
Yiming Zhao ◽  
Huy van Nguyen ◽  
Louise Male ◽  
Philip Craven ◽  
Benjamin R. Buckley ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Cross Coupling ◽  
Product Formation ◽  
Coupling Reactions ◽  
Volume Determination ◽  
Online Tool ◽  
Triazole Derivatives ◽  
Cross Coupling Reactions ◽  
Modelling Approaches

<div>Twelve 1,5-disubtituted and fourteen 5-substituted 1,2,3-triazole derivatives bearing diaryl or dialkyl phosphines at the 5-position were synthesised and used as ligands for palladium-catalysed Suzuki-Miyaura cross-coupling reactions. Bulky substrates were tested, and lead-like product formation was demonstrated. The online tool SambVca 2.0 was used to assess steric parameters of ligands and preliminary buried volume determination using XRD obtained data in a small number of cases proved to be informative. Two modelling approaches were compared for the determination of</div><div>the buried volume of ligands where XRD data was not available. An approach with imposed steric restrictions was found to be superior in leading to buried volume determinations that closely correlate with observed reaction conversions. The online tool LLAMA was used to determine lead-likeness of potential Suzuki-Miyaura cross-coupling products, from which ten of the most lead-like were successfully synthesised. Thus, confirming these readily accessible triazole-containing phosphines as highly suitable ligands for reaction screening and optimisation in drug discovery campaigns.</div>

Nickel-Catalyzed Inter- and Intramolecular Carbon-Sulfur Bond Metathesis by Reversible Arylation

2019 ◽  
Author(s):  
Tristan Delcaillau ◽  
Alessandro Bismuto ◽  
Zhong Lian ◽  
Bill Morandi
Keyword(s):  
Good Yield ◽  
Functional Group ◽  
Product Formation ◽  
Single Bond ◽  
Ring Closing Metathesis ◽  
Catalytic Systems ◽  
Metathesis Reactions ◽  
New Applications ◽  
Further Development ◽  
Sulfur Bond

A nickel-catalyzed carbon-sulfur bond metathesis has been developed to access high-value thioethers. 1,2-bis(dicyclohexylphosphino)ethane (dcype) is essential to promote this highly functional group tolerant reaction. Further, synthetically challenging macrocycles could be obtained in good yield in an unusual example of ring-closing metathesis which does not involve alkene bonds. In-depth organometallic studies support a reversible Ni(0)-Ni(II) pathway to product formation. Overall, this work does not only disclose a more sustainable and more functional group tolerant alternative to previous catalytic systems based on Pd, but also presents new applications and mechanistic information which are highly relevant to the further development and application of unusual single bond metathesis reactions.

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