Kinetics of Moisture Movement in Hygroscopic Materials (I. Theoretical Considerations of Drying Phenomena)

1969 ◽  
Vol 12 (1) ◽  
pp. 0109-0113 ◽  
Author(s):  
Chin Shu Chen and W. H. Johnson
Keyword(s):  
Moisture Movement ◽  
Theoretical Considerations ◽  
Kinetics Of

Kinetics of moisture movement during air drying of sugar beet root

2007 ◽  
Vol 9 (3) ◽  
pp. 317-327 ◽  
Author(s):  
LUIS M. VACCAREZZA ◽  
JOSÉ L. LOMBARDI ◽  
JORGE CHIRIFE
Keyword(s):  
Sugar Beet ◽  
Moisture Movement ◽  
Air Drying ◽  
Beet Root ◽  
Sugar Beet Root ◽  
Kinetics Of

scholarly journals The kinetics of the formation of oxygen films on tungsten

1939 ◽  
Vol 173 (952) ◽  
pp. 13-27 ◽  
Keyword(s):  
Partial Pressure ◽  
Adsorbed Layer ◽  
Preceding Paper ◽  
Accommodation Coefficient ◽  
Experimental Results ◽  
Partial Pressure Of Oxygen ◽  
Steady Pressure ◽  
The Wire ◽  
Theoretical Considerations ◽  
Kinetics Of

1. Experimental results In the preceding paper the application of a method for maintaining a very low steady pressure of oxygen to determine the nature of the complex adsorbed layer of this gas on tungsten has been described. We shall now discuss the use of the method to study the process of formation of the adsorbed film. In figure 1 the accommodation coefficient of neon is plotted as a function of the time. At the instant indicated by the arrow oxygen was admitted to the bulb B (see figure 1 of the preceding paper). It will be seen that at the beginning of the experiment, i.e. before the oxygen was admitted, the amount of impurity in the neon was so small that the drift was practically negligible. An idea of the sort of eonditions that are necessary for the drift to be negligible will be realized from the fact that the partial pressure of oxygen established at the wire in this particular experiment was only 2·3 x 10 -9 mm. of mercury. The gradient da/dt of this and similar curves was measured at various points, and in no case were measurements included for points less than 2 min. after the admission of the oxygen. Experimental and theoretical considerations indicate that by this time a steady pressure of oxygen was established at the wire.

Evaluation of Kinetic Light Scattering as an Approach to the Measurement of Specific Proteins with the Centrifugal Analyzer. II. Theoretical Considerations

1975 ◽  
Vol 21 (12) ◽  
pp. 1735-1746 ◽  
Author(s):  
Gregory J Buffone ◽  
John Savory ◽  
J Hermans
Keyword(s):  
Light Scattering ◽  
Reaction Rate ◽  
Analytical Methodology ◽  
Complex Dimension ◽  
Specific Proteins ◽  
Antibody Complex ◽  
Antigen Antibody ◽  
Theoretical Considerations ◽  
Kinetics Of ◽  
Insight Into

Abstract Development of centrifugal analyzers capable of making light-scattering measurements has prompted the investigation of the application of this type of instrumentation to the measurement of specific proteins. Investigation of antigen/antibody complex dimension and the kinetics of the IgG/anti-IgG reaction as followed by light scattering are examined in relation to improved analytical methodology. The effect of nonspecific protein on the reaction rate has been investigated for IgM, and data are presented that provide insight into the mechanism of the effect of periodic mixing.

scholarly journals The kinetics of the interaction of atomic hydrogen with olefines IV. Results obtained by the foregoing techniques

1949 ◽  
Vol 196 (1047) ◽  
pp. 494-509 ◽  
Keyword(s):  
Double Bond ◽  
Hydrogen Atom ◽  
Atomic Hydrogen ◽  
Experimental Techniques ◽  
Effective Diameter ◽  
Collision Efficiency ◽  
Ethylene Propylene ◽  
Theoretical Considerations ◽  
Kinetics Of ◽  
Effect Of Structure

The experimental techniques and theoretical considerations developed in the previous parts have been utilized in obtaining data on the reactions of the type H + C n H 2 n = C n H 2 n +1 . The olefines used were ethylene, propylene, iso -butene, n -pentene-2 ( cis ), and 2, 3, 3, tri-methyl-butene-1. Certain tentative suggestions as to the effect of structure on the reactivity of the double bond are put forward, but in general, the collision efficiency of a hydrogen atom with an olefine lies between 10 –3 and 10 –4 . It is noted that in the computation of the collision efficiency, it seems to be rather unsatisfactory that the diameter of the whole molecule should be used and it is suggested that perhaps the effective diameter of a more intimate part of the molecule in the region of the double bond should be employed.

A general mechanism for the high-temperature pyrolysis of alkanes. The pyrolysis of isobutane

1974 ◽  
Vol 337 (1609) ◽  
pp. 199-216 ◽  
Keyword(s):  
Experimental Data ◽  
Computer Modelling ◽  
Single Pulse ◽  
General Mechanism ◽  
Methyl Radical ◽  
Hydrogen Atoms ◽  
Wide Range ◽  
Independent Experimental Data ◽  
Theoretical Considerations ◽  
Kinetics Of

A general mechanism is proposed to predict the kinetics of pyrolysis of alkanes at high temperatures (> 1000 K), based on theoretical considerations and on existing literature data. An experimental investigation of the pyrolysis of isobutane in a single-pulse shock tube over the temperature range 1200–1500 K is reported and the results are used to test the proposed mechanism. Computer modelling demonstrates that the mechanism is adequate to explain the experimental data provided that the following are included: ‘forbidden' isomerization reactions, non-Arrhenius rate constants for the methyl radical abstraction reactions, and the addition of hydrogen atoms to olefins. Although further refinement of the mechanism is to be expected as more data becomes available, it already enables pyrolytic behaviour to be predicted for a wide range of alkanes. The investigation also demonstrates how computer modelling can provide insight into a reaction mechanism even when the number of unknowns exceeds the independent experimental data available.

The influence of chromatin compactness on the stoichiometry of the Feulgen-Schiff procedure studied in model films. I. Theoretical kinetics and experiments with films containing isolated deoxyribonucleic acid.

1975 ◽  
Vol 23 (12) ◽  
pp. 882-890 ◽  
Author(s):  
W A Duijndam ◽  
P van Duijn
Keyword(s):  
Theoretical Model ◽  
Deoxyribonucleic Acid ◽  
Experimental Results ◽  
Gel Chromatography ◽  
Ultraviolet Absorbance ◽  
Purine Bases ◽  
Chromatin Compactness ◽  
Schiff Reaction ◽  
Theoretical Considerations ◽  
Kinetics Of

Theoretical considerations on the expected kinetics of the course of the Feulgen-Schiff reaction show that the leveling off of the first part of the Feulgen hydrolysis curve can be explained by the gradual conversion of deoxyribonucleic acid (DNA) to apurinic acid (APA). In addition, depolymerization of DNA caused by the acid used for hydrolysis can account for the decline after a maximum is reached in this curve. With the aid of polyacrylamide model films containing DNA, a detailed study was made both of the process of purine liberation which results in the formation of APA and of the depolymerization processes which cause losses of stainable material. The liberation of purine bases was analyzed by ultraviolet absorbance measurements and by gel chromatography of the neutralized hydrolysing acid. APA concentration was monitored by following the loss of ultraviolet absorbance associated with the purine losses. The depolymerization process was followed by phosphorus determinations. The experimental results were found to be in accordance with the kinetics expected from the theoretical model.

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