Quantum chemical prediction of effects of temperature on hydrolysis rate of penicillin under weakly acidic condition

2022 ◽  
Vol 806 ◽  
pp. 150509
Author(s):  
Haiqin Zhang ◽  
Jichi Bai ◽  
Weifeng Xue ◽  
Yang Xue ◽  
Ya'nan Zhang
Keyword(s):  
Quantum Chemical ◽  
Acidic Condition ◽  
Hydrolysis Rate ◽  
Effects Of Temperature

Hydrolysis kinetics and mechanism of acyl-1,3-diphenyltriazenes

1980 ◽  
Vol 45 (4) ◽  
pp. 1269-1278 ◽  
Author(s):  
Oldřich Pytela ◽  
Miroslav Večeřa ◽  
Pavel Vetešník
Keyword(s):  
Quantum Chemical Calculation ◽  
Quantum Chemical ◽  
Aqueous Media ◽  
Activation Parameters ◽  
Base Catalysis ◽  
Hydrolysis Rate ◽  
Chemical Calculation ◽  
Hydrolysis Kinetics ◽  
Acid And Base ◽  
Acid Catalyzed

The hydrolysis rate constants of 3-(N-methylcarbamoyl)-1,3-diphenyltriazene (I), 3-(N-phenylcarbamoyl)-1,3-diphenyltriazene (II) and 3-acetyl-1,3-diphenyltriazene (III) have been determined in aqueous media within pH 0 to 14, Ho to 3 and H- to 15. The hydrolysis at pH < 2 and pH > 11 show specific acid and base catalysis, respectively, whereas within pH 2 to 11 non-catalyzed hydrolysis takes place. Activation parameters of the non-catalyzed and catalyzed hydrolysis have been determined. Quantum-chemical calculation of 3-carbamoyltriazene (IV) has been carried out by the MINDO/2 method. Hydrolysis mechanism of the studied compounds is suggested for the non-catalyzed, specific acid catalyzed and specific base catalyzed hydrolysis.

scholarly journals Acidic and alkaline bimolecular hydrolysis of substituted formanilides. Computational analysis and modelling of substitution effects

2017 ◽  
Vol 10 (1) ◽  
pp. 35-40
Author(s):  
Martin Michalík ◽  
Peter Škorňa ◽  
Vladimír Lukeš ◽  
Erik Klein
Keyword(s):  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Quantum Chemical ◽  
Computational Analysis ◽  
Hydrolysis Rate ◽  
Substitution Effects ◽  
Chemical Methods ◽  
Quantum Chemical Methods ◽  
Hydrolysis Of

Abstract In this article, the study of 67 compounds representing various para-, meta- and ortho- substituted formanilides is presented. These molecules and the products of their acidic and alkaline hydrolysis were studied using DFT quantum chemical methods in order to calculate the reaction enthalpies. These enthalpies are correlated with the hydrolysis rate constants, kH, published for the acid-catalysed acyl cleavage bimolecular (AAC2) mechanism and the modified base-catalysed acyl cleavage bimolecular (BAC2) mechanism. The found linear dependences can be used for the prediction of rate constants of non-synthesised formanilide derivatives.

EFFECTS OF TEMPERATURE AND PHOSPHATE CONCENTRATION ON RATE OF SODIUM PYROPHOSPHATE AND SODIUM TRIPOLYPHOSPHATE HYDROLYSIS IN SOIL

1977 ◽  
Vol 57 (3) ◽  
pp. 271-278 ◽  
Author(s):  
C. CHANG ◽  
G. J. RACZ
Keyword(s):  
Incubation Temperature ◽  
Sodium Tripolyphosphate ◽  
Phosphate Concentration ◽  
Water Soluble ◽  
Sodium Pyrophosphate ◽  
Hydrolysis Rate ◽  
Rate Of Hydrolysis ◽  
Effects Of Temperature ◽  
Hydrolysis Of ◽  
Pyrophosphate Hydrolysis

Rates of hydrolysis of water-soluble sodium pyrophosphate and sodium tripolyphosphate, applied to soil at 200 ppm P, were extremely rapid (about 2–7%/h) during the 0 to 24- or 0- to 48-h period following phosphate application but decreased with time of incubation. Rates of hydrolysis increased linearly and increased about two- to threefold as temperatures were increased from 5 to 35 C or from 5 to 50 C. Inconsistent results were obtained at temperatures above 50 C. Increases in incubation temperature increased the total amount of added polyphosphate hydrolyzed by the soil in 120 h from about 40 to 70% at 5 C to about 80 to 95% at 35 C and 50 C. Water-soluble polyphosphate hydrolyzed at a greater rate than 0.5 N H2SO4-soluble polyphosphate. However, the effects of temperature on rate of hydrolysis of acid-soluble polyphosphate and water-soluble polyphosphate were similar. Polyphosphate hydrolyzed at a greater rate in the noncalcareous Newdale soil than in the calcareous Lakeland soil. Rate of tripolyphosphate hydrolysis was usually greater than rate of pyrophosphate hydrolysis. Rate of hydrolysis of water-soluble polyphosphate, expressed as %/h, decreased exponentially as concentration of applied polyphosphate increased from 200 to 1,600 ppm. However, rate of orthophosphate production per unit time increased exponentially with increased substrate concentration.

Effects of temperature on life history set the sensitivity to fishing in Atlantic cod Gadus morhua

2014 ◽  
Vol 514 ◽  
pp. 217-229 ◽  
Author(s):  
HY Wang ◽  
LW Botsford ◽  
JW White ◽  
MJ Fogarty ◽  
F Juanes ◽  
...  
Keyword(s):  
Life History ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Effects Of Temperature

Relationships between temperature and Pacific hake distribution vary across latitude and life-history stage

2020 ◽  
Vol 639 ◽  
pp. 185-197 ◽  
Author(s):  
MJ Malick ◽  
ME Hunsicker ◽  
MA Haltuch ◽  
SL Parker-Stetter ◽  
AM Berger ◽  
...  
Keyword(s):  
Life History ◽  
Environmental Effects ◽  
Environmental Conditions ◽  
Vancouver Island ◽  
Additive Models ◽  
Life History Stage ◽  
Fish Stocks ◽  
Merluccius Productus ◽  
Multiple Dimensions ◽  
Effects Of Temperature

Environmental conditions can have spatially complex effects on the dynamics of marine fish stocks that change across life-history stages. Yet the potential for non-stationary environmental effects across multiple dimensions, e.g. space and ontogeny, are rarely considered. In this study, we examined the evidence for spatial and ontogenetic non-stationary temperature effects on Pacific hake Merluccius productus biomass along the west coast of North America. Specifically, we used Bayesian additive models to estimate the effects of temperature on Pacific hake biomass distribution and whether the effects change across space or life-history stage. We found latitudinal differences in the effects of temperature on mature Pacific hake distribution (i.e. age 3 and older); warmer than average subsurface temperatures were associated with higher biomass north of Vancouver Island, but lower biomass offshore of Washington and southern Vancouver Island. In contrast, immature Pacific hake distribution (i.e. age 2) was better explained by a nonlinear temperature effect; cooler than average temperatures were associated with higher biomass coastwide. Together, our results suggest that Pacific hake distribution is driven by interactions between age composition and environmental conditions and highlight the importance of accounting for varying environmental effects across multiple dimensions.

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