Dynamics and Kinetics of Methanol‐Graphite Interactions at Low Surface Coverage

In this paper we investigate three two-dimensional in space mathematical models of the kinetics of unimolecular heterogeneous reactions proceeding onto planar surfaces. All models include the diffusion of the reactant from a bounded vessel towards an adsorbent, adsorption of the molecules of the reactant, their desorption, conversion (reaction) of the adsorbate into a product, instantaneous product desorption, and the diffusion of the product from the adsorbent into the same vessel. One of these models is based on the Langmuir-type kinetics of the surface reactions, the other one is based on the local steady-state value of the surface coverage, and the last one, in addition to the first model, involves the diffusion of the adsorbate along the adsorbent. Diffusivity of all species is assumed to be constant. Models were solved numerically by using the finite difference technique. By changing input parameters the effects of the rate constants of the reactant adsorption, desorption, and reaction and the influence of the surface diffusion of the adsorbate and approximation of the surface coverage by its steady-state value on the kinetics of surface reactions were studied numerically.

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The effect of surface coverage by adsorbed oxygen on the kinetics of oxygen reduction at oxide free platinum

Electrochimica Acta ◽

10.1016/0013-4686(73)87026-4 ◽

1973 ◽

Vol 18 (12) ◽

pp. 945-951 ◽

Cited By ~ 21

Author(s):

Marta Paucirova ◽

D.M. Drazic ◽

A. Damjanovic

Keyword(s):

Oxygen Reduction ◽

Surface Coverage ◽

Adsorbed Oxygen ◽

Kinetics Of ◽

Effect Of Surface

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Heparin Stimulates Staphylococcus aureus Biofilm Formation

Infection and Immunity ◽

10.1128/iai.73.8.4596-4606.2005 ◽

2005 ◽

Vol 73 (8) ◽

pp. 4596-4606 ◽

Cited By ~ 180

Author(s):

Robert M. Q. Shanks ◽

Niles P. Donegan ◽

Martha L. Graber ◽

Sarah E. Buckingham ◽

Michael E. Zegans ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Biofilm Formation ◽

Surface Coverage ◽

Anticoagulant Activity ◽

Bloodstream Infections ◽

Dependent Manner ◽

Abiotic Surfaces ◽

Primary Attachment ◽

Kinetics Of ◽

Stimulation Of

ABSTRACT Heparin, known for its anticoagulant activity, is commonly used in catheter locks. Staphylococcus aureus, a versatile human and animal pathogen, is commonly associated with catheter-related bloodstream infections and has evolved a number of mechanisms through which it adheres to biotic and abiotic surfaces. We demonstrate that heparin increased biofilm formation by several S. aureus strains. Surface coverage and the kinetics of biofilm formation were stimulated, but primary attachment to the surface was not affected. Heparin increased S. aureus cell-cell interactions in a protein synthesis-dependent manner. The addition of heparin rescued biofilm formation of hla, ica, and sarA mutants. Our data further suggest that heparin stimulation of biofilm formation occurs neither through an increase in sigB activity nor through an increase in polysaccharide intracellular adhesin levels. These finding suggests that heparin stimulates S. aureus biofilm formation via a novel pathway.

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Adsorption affinity of Zn (II) ions for nanostructured zirconium phosphate/silica or titania composites

Applied Nanoscience ◽

10.1007/s13204-021-01722-w ◽

2021 ◽

Author(s):

W. Janusz ◽

V. Sydorchuk ◽

E. Skwarek ◽

S. Khalameida ◽

J. Skubiszewska-Zięba ◽

...

Keyword(s):

Zirconium Phosphate ◽

Surface Coverage ◽

Complete Removal ◽

Mechanical Processing ◽

Zinc Ions ◽

Titanium Oxides ◽

Initial Concentration ◽

Adsorption Affinity ◽

Kinetics Of ◽

Silica And Titania

AbstractThe paper presents the kinetics of Zn (II) ions adsorption as well as its dependence as a function of pH on nanostructured zirconium phosphate and its composites with silica and titania. The nanostructured zirconium phosphate-containing composites were obtained by mechanical processing in the Pulverisette-7 (Fritsch Gmbh) mill. The obtained composites were characterized by a heterogeneous surface coverage of silica gel or titanium oxides. Zinc ions adsorption studies on these adsorbents showed practically complete removal of Zn (II) from aqueous solutions with an initial concentration of < 0.0001 mol/dm3 and a pH > 4 within 10 min.

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COMPARATIVE STUDY ON THE ADSORPTION PROCESSES OF ALKANETHIOL AND ALKANEDITHIOL ON GOLD

Surface Review and Letters ◽

10.1142/s0218625x10014211 ◽

2010 ◽

Vol 17 (04) ◽

pp. 397-403 ◽

Cited By ~ 4

Author(s):

HUI HE ◽

YAN GUO ◽

SHOUFU WANG ◽

YAQING JIANG

Keyword(s):

Self Assembly ◽

Surface Coverage ◽

Self Assembled Monolayers ◽

Diffusion Controlled ◽

Assembled Monolayers ◽

Adsorption Processes ◽

Kinetics Of Formation ◽

Initial Adsorption ◽

Adsorption Rates ◽

Kinetics Of

The kinetics of formation of self-assembled monolayers on gold generated by the adsorption of 1-octanethiol and 1,8-octanedithiol were explored by electrochemistry measurement. The time dependence of capacitance and surface coverage supported that the adsorption of thiols typically processed with a two-step adsorption consisted of a fast initial adsorption and a slowly following reorganization. From the function of surface coverage versus time, one could get rate constants of adsorption of thiols, and the adsorption process was demonstrated to follow a diffusion-controlled Langmuir model. A comparison of the adsorption rates for different concentration between 1-octanethiol and 1,8-octanedithiol revealed that their adsorption processes were almost identical and independent on the concentration, inferring that only one sulfur atom contributed to the self-assembly of dithiol molecule.

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