Mechanism and Kinetics of Stabilization Reactions of Polyacrylonitrile and Related Copolymers III. Comparison among the Various Types of Copolymers as Viewed from Isothermal DSC Thermograms and FT-IR Spectral Changes

The reaction of an aqueous solution of formaldehyde with gelatin dispersed in a potassium bromide pellet is monitored in real time by FT-IR spectroscopy. Principal component regression analysis of the spectra recorded at different times is carried out. On the whole, the latter results and the observed spectral changes are in agreement with a previously reported interpretation for the kinetics of the crosslinking reaction of gelatin with formaldehyde, according to which the reaction is initialized by the lysine–methylol formation and is subsequently followed by arginine–methylol, which, in turn, reacts with lysine–methylol to originate arginine–lysine crosslinks.

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Design and Evaluation of Sustained Release Solid Dispersions of Verapamil Hydrochloride

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2010.3.4.10 ◽

2011 ◽

Vol 3 (4) ◽

pp. 1252-1262

Author(s):

Swain S K ◽

Niranjan Patra Patra ◽

Sruti J ◽

M.E. Bhanoji Rao

Keyword(s):

Solid Dispersions ◽

Verapamil Hydrochloride ◽

Ir Studies ◽

Dissolution Properties ◽

Rate Of Dissolution ◽

Release Studies ◽

Ft Ir ◽

Mechanism And Kinetics ◽

Model Drug ◽

Kinetics Of

The Purpose of this study was to prepare and characterize solid dispersions of this antiarrhythmic drug Verapamil hydrochloride (VPH) with HPMCK4M, EudragitRSPO and their combination with a view to sustain its dissolution properties. Investigation of the properties of the prepared solid dispersions were performed using release studies and Fourier transform infrared (FT-IR). The results obtained showed that the rate of dissolution of Verapamil hydrochloride was considerably more sustained when formulated in solid dispersions with HPMCK4M and Eudragit RSPO as compared with pure drug and physical mixtures. FT-IR studies confirmed absence of any possible solid state drug and polymer interactions. In order to establish the mechanism and kinetics of drug release, the experimental data was fitted to different kinetic models likes zero order, first order, Higuchi’s model, korsmeyer peppa’s model. From the above research it may be concluded that HPMCK4M acts as a better release retardant for the model drug.

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Work function in studying mechanism and kinetics of heterogeneous reactions in the system : oxygen-nonstoichiometric oxides

Journal de Chimie Physique ◽

10.1051/jcp/1978750689 ◽

1978 ◽

Vol 75 ◽

pp. 689-702 ◽

Cited By ~ 10

Author(s):

Janusz Nowotny

Keyword(s):

Work Function ◽

Heterogeneous Reactions ◽

Nonstoichiometric Oxides ◽

Mechanism And Kinetics ◽

Kinetics Of

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The Influence of CaF2 and AIF3 upon Mechanism and Kinetics of the Anodic Reaction in Cryolite-Alumina Melts

High Temperature Material Processes An International Quarterly of High-Technology Plasma Processes ◽

10.1615/hightempmatproc.v3.i2-3.150 ◽

1999 ◽

Vol 3 (2-3) ◽

pp. 311-319

Keyword(s):

Anodic Reaction ◽

Mechanism And Kinetics ◽

Kinetics Of

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Oil extraction from the sunflower seeds, mechanism and kinetics of the process

Chemistry, Technology and Application of Substances ◽

10.23939/ctas2020.01.155 ◽

2020 ◽

Vol 3 (1) ◽

pp. 155-160

Author(s):

Ye. M. Semenyshyn ◽

◽

V. M. Atamanyuk ◽

O. Ya. Dobrovetska ◽

T. I. Rymar ◽

...

Keyword(s):

Oil Extraction ◽

Sunflower Seeds ◽

Mechanism And Kinetics ◽

Kinetics Of

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Studies on the Behavior Some Paints in Electro-insulating Fluid Based on Vegetable Esters

Revista de Chimie ◽

10.37358/rc.18.5.6276 ◽

2018 ◽

Vol 69 (5) ◽

pp. 1139-1144

Author(s):

Iosif Lingvay ◽

Adriana Mariana Bors ◽

Livia Carmen Ungureanu ◽

Valerica Stanoi ◽

Traian Rus

Keyword(s):

Structural Changes ◽

Oxidation Processes ◽

High Oleic ◽

Painting Materials ◽

Insulating Paper ◽

Different Types ◽

Mechanism And Kinetics ◽

Kinetics Of ◽

Natural Ester

For the purpose of using three different types of painting materials for the inner protection of the transformer vats, their behavior was studied under actual conditions of operation in the transformer (thermal stress in electro-insulating fluid based on the natural ester in contact with copper for electro-technical use and electro-insulating paper). By comparing determination of the content in furans products (HPLC technique) and gases formed (by gas-chromatography) in the electro-insulating fluid (natural ester with high oleic content) thermally aged at 130 �C to 1000 hours in closed glass vessels, it have been found that the presence the investigated painting materials lead to a change in the mechanism and kinetics of the thermo-oxidation processes. These changes are supported by oxygen dissolved in oil, what leads to decrease both to gases formation CO2, CO, H2, CH4, C2H4 and C2H6) and furans products (5-HMF, 2-FOL, 2 -FAL and 2-ACF). The painting materials investigated during the heat treatment applied did not suffer any remarkable structural changes affecting their functionality in the electro-insulating fluid based on vegetable esters.

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