The search for the active base operating in alkoxide promoted E2 reactions in low polar solvents: A kinetic analysis of the elusive problem

1981 ◽  
Vol 46 (13) ◽  
pp. 3247-3263 ◽  
Author(s):  
Jiří Závada ◽  
Magdalena Pánková ◽  
Antonín Vítek
Keyword(s):  
Experimental Data ◽  
Kinetic Analysis ◽  
Kinetic Models ◽  
The Other ◽  
Polar Solvents ◽  
Tert Butanol ◽  
Isomer Distribution ◽  
Single Substrate ◽  
The One ◽  
Active Base

Partial kinetic orders in base for 1-decene, cis-2-decene and trans-2-decene formation from the reaction of 2-decyl bromide with t-C4H9OK in tetrahydrofuran and in tert-butanol and with t-C4H9ONa in tert-butanol have been determined and their significance for assessment of active base has been probed. It has been ascertained that assessment of active base in alkoxide promoted E2 reactions is model-dependent. An unambiguous evidence has been provided by a kinetic analysis of the effect of base concentration on olefin-isomer distribution in the reaction. Two alternative kinetic models of this effect have been devised, the one assuming a competition of several active base species for a single substrate and the other a competition between an uncomplexed and alkoxide-complexed substrate for a single active base. Compatibility of both kinetic models with experimental data has been demonstrated.

A New Adsorption Rate Equation in Batch Systems

2018 ◽  
Author(s):  
yongson hong ◽  
Kye-Ryong Sin ◽  
Jong-Su Pak ◽  
Chol-Min Pak
Keyword(s):  
Experimental Data ◽  
Kinetic Analysis ◽  
Adsorption Kinetics ◽  
Rate Equation ◽  
Kinetic Models ◽  
Adsorption Kinetic ◽  
Adsorption Rate ◽  
Batch Systems ◽  
New View

<p><b>In this paper, the deficiencies and cause of previous adsorption kinetic models were revealed, new adsorption rate equation has been proposed and its validities were verified by kinetic analysis of various experimental data.</b> <b>This work is a new view on the adsorption kinetics rather than a comment on the previous adsorption papers.</b></p>

The Interaction of Carbon Black with Sulfur, MBT and TMTD in Vulcanization

1961 ◽  
Vol 34 (2) ◽  
pp. 588-599 ◽  
Author(s):  
G. A. Blokh ◽  
Ch. L. Melamed
Keyword(s):  
Experimental Data ◽  
Carbon Black ◽  
Chemical Reactions ◽  
The Other ◽  
Considerable Importance ◽  
Physical Aspect ◽  
Active Centers ◽  
Other Hand ◽  
The One

Abstract The experimental data collected on the interaction of active centers of carbon black with the rubber on the one hand and of the active centers of carbon black with the sulfur and accelerators, and also with the antioxidants, on the other hand, provide a sound basis for belief that the problem of reinforcement of rubber by active fillers in the process of vulcanization cannot be explained from the physical aspect alone. The facts indicate the considerable importance of the chemical reactions between the active groups of carbon black and the compounding ingredients in the course of vulcanization.

Case and φ-feature agreement in advanced L2 Spanish grammars

2002 ◽  
Vol 2 ◽  
pp. 71-86 ◽  
Author(s):  
Florencia Franceschina
Keyword(s):  
Experimental Data ◽  
The Other ◽  
Gender Agreement ◽  
Advanced Learners ◽  
Number Agreement ◽  
Functional Features ◽  
L2 Spanish ◽  
And Gender ◽  
The One ◽  
Case Number

One account of divergence in advanced L2 grammars is that speakers fail to acquire functional features in the L2 that are not part of the L1 inventory, and that this leads to non-native representations. Since this idea was first proposed by Hawkins and Chan (1997), few studies have provided the type of data which would allow for it to be adequately tested. This paper presents experimental data from two studies of the acquisition of Case, number and gender agreement in a group of advanced learners of Spanish who are L1 speakers of English, French, German, Greek, Italian and Portuguese. Differences were found between accuracy on Case and number agreement on the one hand, and gender agreement on the other, in ways predicted by the Failed Functional Features hypothesis.

scholarly journals The homogeneous catalysis of gaseous reactions by iodine. The decomposition of propionic aldehyde, and a general discussion

1933 ◽  
Vol 142 (846) ◽  
pp. 77-88 ◽  
Keyword(s):  
Kinetic Analysis ◽  
Homogeneous Catalysis ◽  
Chemical Change ◽  
Point Of View ◽  
The Other ◽  
Side Reactions ◽  
General Point ◽  
Chemical Changes ◽  
Secondary Reactions ◽  
The One

Previous papers have dealt with the homogeneous catalysis of the decomposition of ethers and of acetaldehyde by iodine. The problem of the mechanism of these catalysed reactions can be approached in two ways: on the one hand, by seeking to obtain as complete a picture as possible of the types of chemical change which are susceptible to the action of a given catalyst, and, the catalysts which will promote a given chemical change; and, on the other hand, by investigating in detail the kinetics and molecular statistics of individual reactions. Experiments on the different kinds of reaction which iodine will catalyse are being published elsewhere. Most of the chemical changes have involved too many side reactions, or secondary reactions with the catalyst, to be suitable for complete kinetic analysis. Nevertheless, they show the chemical specificity of the action of iodine in the clearest manner, and this aspect of the problem is discussed from a general point of view in the last section of the present paper.

A New Adsorption Rate Equation in Batch Systems

2018 ◽  
Author(s):  
yongson hong ◽  
Kye-Ryong Sin ◽  
Jong-Su Pak ◽  
Chol-Min Pak
Keyword(s):  
Experimental Data ◽  
Kinetic Analysis ◽  
Adsorption Kinetics ◽  
Rate Equation ◽  
Kinetic Models ◽  
Adsorption Kinetic ◽  
Adsorption Rate ◽  
Batch Systems ◽  
New View

<p><b>In this paper, the deficiencies and cause of previous adsorption kinetic models were revealed, new adsorption rate equation has been proposed and its validities were verified by kinetic analysis of various experimental data.</b> <b>This work is a new view on the adsorption kinetics rather than a comment on the previous adsorption papers.</b></p>

Study of Electromagnetic Multipole Transition Half-Lives of One-Hole 15O–15N and One-Particle 17O–17F Mirror Nuclei

2013 ◽  
Vol 68 (10-11) ◽  
pp. 709-714 ◽  
Author(s):  
Mohammadreza Pahlavani ◽  
Behnam Firoozi
Keyword(s):  
Experimental Data ◽  
Wave Functions ◽  
The Other ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Matrix Elements ◽  
Saxon Potential ◽  
N Isotopes ◽  
The One ◽  
Theoretical Results

Energy spectrum and wave functions are obtained numerically with a potential consisting of Woods-Saxon, Coulomb, and spin-orbit coupling parts for the nuclei 15O, 15N, 17O, and 17F. The radial parts of the wave functions are used to calculate some matrix elements of electromagnetic transitions. These results are applied to calculate half-lives of low-lying exited states in the one-particle 17O and 17F as well as in the one-hole 15O and 15N isotopes. The calculated half-lives are compared with available experimental and theoretical results based on harmonic oscillator wave functions and Weisskopf units. In comparison with the results calculated from the other methods, our results based on the Woods-Saxon potential indicate a satisfactory agreement with accessible experimental data.

Modeling the Combined Effect of pH and Temperature on the Heat Resistance of Bacillus stearothermophilus Spores Heated in a Multicomponent Food Extract

2001 ◽  
Vol 64 (10) ◽  
pp. 1631-1635 ◽  
Author(s):  
W. TEJEDOR ◽  
M. RODRIGO ◽  
A. MARTÍNEZ
Keyword(s):  
Experimental Data ◽  
Heat Resistance ◽  
Mathematical Models ◽  
Bacillus Stearothermophilus ◽  
Combined Effect ◽  
The Other ◽  
Distilled Water ◽  
Effect Of Ph ◽  
Food Extract ◽  
The One

The combined effect of pH and temperature on the heat resistance of Bacillus stearothermophilus spores heated in an extract of complex food was studied. The results showed that, in general, reducing the pH reduced the heat resistance of the spores. Similarly, the value for the D parameter in the nonacidified extract was between 30 and 70% lower than the one obtained with double-distilled water. This result once again shows the importance of the substrate in inactivation studies of microorganisms. The experimental data were used to carry out a comparison of two predictive mathematical models of inactivation, one based on a multiparametric regression obtained in this study and the other obtained from the bibliography and based on a linear-Bigelow equation. Both models predict reasonably well, although the multiparametric model presented a slightly better accuracy factor (1.11) than the one obtained with the linear-Bigelow equation (1.13).

scholarly journals Utilization of MOSFET transistor as an electronic load to trace I-V and P-V curve of a solar panel

2021 ◽  
Vol 229 ◽  
pp. 01021
Author(s):  
Abdellah Asbayou ◽  
Mohamed Agdam ◽  
Amine Aamoume ◽  
Ahmed Soussi ◽  
Ahmed Ihla ◽  
...  
Keyword(s):  
Experimental Data ◽  
Simple Technique ◽  
The Other ◽  
Variable Load ◽  
Electrical Behavior ◽  
Variable Resistor ◽  
Photovoltaic Panel ◽  
Standard Temperature ◽  
Electronic Load ◽  
The One

To understand the electrical behavior of a photovoltaic panel, it is necessary to know the characteristic Ipv = f(Vpv). The best way to obtainthis I-V curve is to use a variable resistor. This paper proposes a new and simple technique based on a MOSFET transistor as a variable load, which whose gate voltage is controlled by an RC filter from the Arduino. A comparison under standard temperature and illumination conditions between the manufacturer’s datasheet with the simulation by MATLAB/Simulink on the one hand, and on the other hand between the manufacturer’s datasheet with the experimental data for the evaluation of this technique that has been performed.

scholarly journals Putting Biomedical Ontologies to Work

2010 ◽  
Vol 49 (02) ◽  
pp. 135-140 ◽  
Author(s):  
M. Brochhausen ◽  
B. Smith
Keyword(s):  
Experimental Data ◽  
General Trend ◽  
Information Resources ◽  
The Other ◽  
Ontology Development ◽  
Biomedical Ontologies ◽  
Snomed Ct ◽  
User Friendliness ◽  
Cross Domain ◽  
The One

Summary Objectives: Biomedical ontologies exist to serve integration of clinical and experimental data, and it is critical to their success that they be put to widespread use in the annotation of data. How, then, can ontologies achieve the sort of user-friendliness, reliability, cost-effectiveness, and breadth of coverage that is necessary to ensure extensive usage? Methods: Our focus here is on two different sets of answers to these questions that have been proposed, on the one hand in medicine, by the SNOMED CT community, and on the other hand in biology, by the OBO Foundry. We address more specifically the issue as to how adherence to certain development principles can advance the usability and effectiveness of an ontology or terminology resource, for example by allowing more accurate maintenance, more reliable application, and more efficient interoperation with other ontologies and information resources. Results: SNOMED CT and the OBO Foundry differ considerably in their general approach. Nevertheless, a general trend towards more formal rigor and cross-domain interoperability can be seen in both and we argue that this trend should be accepted by all similar initiatives in the future. Conclusions: Future efforts in ontology development have to address the need for harmonization and integration of ontologies across disciplinary borders, and for this, coherent formalization of ontologies is a prerequisite.

Phases of hormone action

1926 ◽  
Vol 22 (3) ◽  
pp. 354-355
Author(s):  
R. Luria
Keyword(s):  
Experimental Data ◽  
Salivary Glands ◽  
The Body ◽  
The Other ◽  
Hormone Action ◽  
Series Of Experiments ◽  
Set Up ◽  
The One

Phases of hormone action. Proceeding from the provisions of the Kraus school, which established the value of electrolytes as a factor determining the course of life processes in the body, on the one hand, and on the basis of experimental data on the antagonism between insulin and adrenaline, on the other, V.M. Kogan, Kamenev and Mants (Pr. Doctor, 1925, No. 5) set up a series of experiments to study the effect of increments on the separation of the salivary glands in various combinations of insulin, adrenaline and electrolytes K and Ca.

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