Pressure and temperature dependence of the rate constants for the association reactions of vinoxy and 1-methylvinoxy radicals with nitric oxideElectronic supplementary information (ESI) available: Experimental conditions and results for reactions (R1) and (R2). G2 molecular properties of the key structures for CH2CHO + NO and CH2C(CH3)O + NO reaction kinetics. See http://www.rsc.org/suppdata/cp/b1/b110100e/

2002 ◽  
Vol 4 (13) ◽  
pp. 2941-2949 ◽  
Author(s):  
Eric Delbos ◽  
Pascal Devolder ◽  
Lahcen ElMaimouni ◽  
Christa Fittschen ◽  
Katarzyna Brudnik ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Reaction Kinetics ◽  
Rate Constants ◽  
Molecular Properties ◽  
Supplementary Information ◽  
Experimental Conditions

A kinetic modeling study of ethylene pyrolysis

2000 ◽  
Vol 78 (1) ◽  
pp. 16-25 ◽  
Author(s):  
John M Roscoe ◽  
Alain R Bossard ◽  
Margaret H Back
Keyword(s):  
Activation Energy ◽  
Kinetic Model ◽  
Temperature Dependence ◽  
Key Words ◽  
Kinetic Modeling ◽  
Rate Constants ◽  
Preexponential Factor ◽  
Isomerization Reaction ◽  
Experimental Measurements ◽  
Experimental Conditions

A kinetic model is presented for the pyrolysis of ethylene at pressures ranging from 0.8 to 27 kPa and temperatures from 774 to 1023 K. The model is based on experimental measurements of C2H2, C2H6, C3H6, 1-C4H8, and 1,3-C4H6. In this temperature range the reaction is initiated by the disproportionation of C2H4 and the observed products result from reactions of the C2H3 and C2H5 radicals produced in this process. The C2H2 and 1,3-C4H6 result from reactions of C2H3 while C2H6, C3H6, and 1-C4H8 result from reactions of C2H5. C2H2 is produced exclusively by the decomposition of the C2H3 radical. This process is in its falloff region throughout the range of experimental conditions examined and the yield of C2H2 provides a measure of the degree of falloff. The production of 1,3-C4H6 is controlled by the reaction C4H7 –> C4H6 + H. The rate constants for this reaction were independent of pressure and are given as a function of temperature by k = 2.2 × 1013 exp (-19.6 × 103/T). Production of C2H6 is controlled by the reaction C2H5 + C2H4 –> C2H6 + C2H3. The rate constant for this reaction is given as a function of temperature by k = 5.83 × 1011 exp (-14.6 × 103/T). C3H6 is produced by decomposition of 2-C4H9 and is controlled kinetically by the isomerization reaction 1-C4H9 –> 2-C4H9. The temperature dependence of the rate constants obtained for this reaction leads to a preexponential factor of approximately 3 × 1016 and an activation energy of approximately 200 kJ mol-1. The yield of 1-C4H8 is controlled by 1-C4H9 –> 1-C4H8 + H. The rate constants for this reaction were independent of pressure and are given as a function of temperature by k = 2.97 × 1012 exp (-17.1 × 103/T). Key words: kinetic modeling, ethylene pyrolysis.

Salt effect in hydrolysis of 3-acyl-1,3-diphenyltriazenes

1981 ◽  
Vol 46 (12) ◽  
pp. 3104-3109 ◽  
Author(s):  
Miroslav Ludwig ◽  
Oldřich Pytela ◽  
Miroslav Večeřa
Keyword(s):  
Sodium Chloride ◽  
Temperature Dependence ◽  
Potassium Chloride ◽  
Rate Constants ◽  
Zinc Sulphate ◽  
Salt Effect ◽  
Sodium Sulphate ◽  
Potassium Sulphate ◽  
Lithium Sulphate ◽  
Hydrolysis Of

Rate constants of non-catalyzed hydrolysis of 3-acetyl-1,3-diphenyltriazene (I) and 3-(N-methylcarbamoyl)-1,3-diphenyltriazene (II) have been measured in the presence of salts (ammonium chloride, potassium chloride, lithium chloride, sodium chloride and bromide, ammonium sulphate, potassium sulphate, lithium sulphate, sodium sulphate and zinc sulphate) within broad concentration ranges. Temperature dependence of the hydrolysis of the substrates studied has been measured in the presence of lithium sulphate within temperature range 20° to 55 °C. The results obtained have been interpreted by mechanisms of hydrolysis of the studied substances.

Radiolysis studies on the corrosion inhibitors 1 -hexyn-3-ol, cinnamonitrile, and 1,3-diethyl-2-thiourea

1995 ◽  
Vol 73 (12) ◽  
pp. 2137-2142 ◽  
Author(s):  
A.J. Elliot ◽  
M.P. Chenier ◽  
D.C. Ouellette
Keyword(s):  
Hydrogen Atom ◽  
Hydroxyl Radical ◽  
Temperature Dependence ◽  
Rate Constant ◽  
Rate Constants ◽  
Corrosion Inhibitors ◽  
Hydrated Electron

In this publication we report: (i) the rate constants for reaction of the hydrated electron with 1-hexyn-3-ol ((8.6 ± 0.3) × 108 dm3 mol−1 s−1 at 18 °C), cinnamonitrile ((2.3 ± 0.2) × 1010 dm3 mol−1 s−1 at 20 °C), and 1,3-diethyl-2-thiourea ((3.5 ± 0.3) × 108 dm3 mol−1 s−1 at 22 °C). For cinnamonitrile and diethylthiourea, the temperature dependence up to 200 °C and 150 °C, respectively, is also reported; (ii) the rate constants for the reaction of the hydroxyl radical with 1-hexyn-3-ol ((5.5 ± 0.5) × 109 dm3 mol−1 s−1 at 20 °C), cinnamonitrile ((9.2 ± 0.3) × 109 dm3 mol−1 s−1 at 21 °C), and diethylthiourea ((8.0 ± 0.8) × 108 dm3 mol−1 s−1 at 22 °C). For cinnamonitrile, the temperature dependence up to 200 °C is also reported; (iii) the rate constant for the hydrogen atom reacting with 1-hexyn-3-ol ((4.3 ± 0.4) × 109 dm3 mol−1 s−1 at 20 °C). Keywords: radiolysis, corrosion inhibitors, rate constants.

scholarly journals Ribo-ODDR: Oligo design pipeline for experiment-specific rRNA depletion in ribo-seq

2021 ◽  
Author(s):  
Ferhat Alkan ◽  
Joana Silva ◽  
Eric Pintó Barberà ◽  
William J Faller
Keyword(s):  
Ribosome Profiling ◽  
Supplementary Information ◽  
Experimental Conditions ◽  
Computational Framework ◽  
Rna Translation ◽  
Rrna Depletion ◽  
Selection For ◽  
Nucleotide Resolution ◽  
User Friendly ◽  
Oligo Design

Abstract Motivation Ribosome Profiling (Ribo-seq) has revolutionized the study of RNA translation by providing information on ribosome positions across all translated RNAs with nucleotide-resolution. Yet several technical limitations restrict the sequencing depth of such experiments, the most common of which is the overabundance of rRNA fragments. Various strategies can be employed to tackle this issue, including the use of commercial rRNA depletion kits. However, as they are designed for more standardized RNAseq experiments, they may perform suboptimally in Ribo-seq. In order to overcome this, it is possible to use custom biotinylated oligos complementary to the most abundant rRNA fragments, however currently no computational framework exists to aid the design of optimal oligos. Results Here, we first show that a major confounding issue is that the rRNA fragments generated via Ribo-seq vary significantly with differing experimental conditions, suggesting that a “one-size-fits-all” approach may be inefficient. Therefore we developed Ribo-ODDR, an oligo design pipeline integrated with a user-friendly interface that assists in oligo selection for efficient experiment-specific rRNA depletion. Ribo-ODDR uses preliminary data to identify the most abundant rRNA fragments, and calculates the rRNA depletion efficiency of potential oligos. We experimentally show that Ribo-ODDR designed oligos outperform commercially available kits and lead to a significant increase in rRNA depletion in Ribo-seq. Availability Ribo-ODDR is freely accessible at https://github.com/fallerlab/Ribo-ODDR Supplementary information Supplementary data are available at Bioinformatics online.

A kinetic standard for precise calibration of spectrophotometer cell temperature.

1981 ◽  
Vol 27 (5) ◽  
pp. 753-755 ◽  
Author(s):  
P A Adams ◽  
M C Berman
Keyword(s):  
Temperature Dependence ◽  
Rate Constants ◽  
Cell Temperature ◽  
First Order ◽  
Order Rate ◽  
Acid Catalyzed ◽  
Pseudo First Order ◽  
Hydrolysis Of

Abstract We describe a simple, highly reproducible kinetic technique for precisely measuring temperature in spectrophotometric systems having reaction cells that are inaccessible to conventional temperature probes. The method is based on the temperature dependence of pseudo-first-order rate constants for the acid-catalyzed hydrolysis of N-o-tolyl-D-glucosylamine. Temperatures of reaction cuvette contents are measured with a precision of +/- 0.05 degrees C (1 SD).

scholarly journals Reactivity of cyclohex-1-enylcarboxylic and 2-methylcyclohex-1-enylcarboxylic acids with diazodiphenylmethane in aprotic solvents

2000 ◽  
Vol 65 (12) ◽  
pp. 839-846
Author(s):  
Jasmina Nikolic ◽  
Gordana Uscumlic ◽  
Vera Krstic
Keyword(s):  
Hydrogen Bond ◽  
Rate Constants ◽  
Kinetic Data ◽  
Linear Regression Analysis ◽  
Spectroscopic Method ◽  
Reaction Rates ◽  
Aprotic Solvents ◽  
Experimental Conditions ◽  
Hydrogen Bond Acceptor ◽  
Protic Solvents

Rate constants for the reaction of diazodiphenylmethane with cyclohex-1-enylcarboxylic acid and 2-methylcyclohex-1-enylcarboxylic acid were determined in nine aprotic solvents, as well as in seven protic solvents, at 30?C using the appropriate UV-spectroscopic method. In protic solvents the unsubsituted acid displayed higher reaction rates than the methyl-substituted one. The results in aprotic solvents showed quite the opposite, and the reaction rates were considerably lower. In order to explain the obtained results through solvent effects, reaction rate constants (k) of the examined acids were correlated using the total solvatochromic equation of the form: log k=logk0+s?*+a?+b?, where ?* is the measure of the solvent polarity, a represents the scale of the solvent hydrogen bond donor acidities (HBD) and b represents the scale of the solvent hydrogen bond acceptor basicities (HBA). The correlation of the kinetic data were carried out by means of multiple linear regression analysis and the opposite effects of aprotic solvents, as well as the difference in the influence of protic and aprotic solvents on the reaction of the two examined acids with DDM were discussed. The results presented in this paper for cyclohex-1-enylcarboxylic and 2-methylcyclohex-1-enylcarboxylic acids were compared with the kinetic data for benzoic acid obtained in the same chemical reaction, under the same experimental conditions.

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