Dépouillements

Development of a control algorithm for the optimized soaking of cured hides / Karel Kolomaznik in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CI, N° 9 (09/2006)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CI, N° 9 (09/2006) . - p. 309-316 Titre : Development of a control algorithm for the optimized soaking of cured hides Type de document : texte imprimé Auteurs : Karel Kolomaznik, Auteur ; Z. Prokopova, Auteur ; Vladimir Vasek, Auteur ; David G. Bailey, Auteur Année de publication : 2006 Article en page(s) : p. 309-316 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The advantages and possible complications of mathematical simulations - indirect modelling of tanning processes are discussed in the Introduction. As an example of deterministic models of mathematical simulation, a diffusion model for the cured hide soaking operation is presented. The minima of the main operating costs are determined, following from their dependence on the consumption of the soaking liquid - technological water. The minimum of the costs depends, besides economical and technological parameters, on the values of physical constants - the speed constant of the dissolving of the surface solid salt (pre-soak washing), the transport parameter that enables a qualified approximation of the duration of the soaking operation itself, and the effective diffusion coefficient of salt in the inner volume of the cured hide. A possible occurrence of concentration shock is modelled, as well as a method of its prevention. Experimental methods for the determination of physical constants are also presented. En ligne : https://drive.google.com/file/d/13IrapmCZ1GKnvbwCJtVejPFnj0it8Peq/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3976 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
005598	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Interaction of aluminum and hydrolysable tannin polyphenols : An approach to understanging the mechanism of aluminum vegetable combination tannage / Balaraman Madhan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CI, N° 9 (09/2006)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CI, N° 9 (09/2006) . - p. 317-323 Titre : Interaction of aluminum and hydrolysable tannin polyphenols : An approach to understanging the mechanism of aluminum vegetable combination tannage Type de document : texte imprimé Auteurs : Balaraman Madhan, Auteur ; Rathinam Aravindhan, Auteur ; M. S. Siva, Auteur ; S. Sadulla, Auteur ; Jonnalagadda Raghava Rao, Auteur ; Balachandran Unni Nair, Auteur Année de publication : 2006 Article en page(s) : p. 317-323 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Semi-metal tanning systems have gained importance in recent times as an alternative for chrome tanning. Many reports are available regarding vegetable-aluminum combination tanning systems, but the mechanism of interaction between the aluminum and the vegetable tanning molecules has not been elucidated in detail. This study involves the determination of the complexing behavior of aluminum with the hydrolysable tannin, myrobalan and with the molecular species viz., gallic and tannic acid of hydrolysable tannin. Stoichiometry and binding constant of the polyphenolics-aluminum complex have been studied. It is observed that aluminum exhibits strong binding with hydrolysable tannin polyphenols. Externally prepared myrobalan-aluminum complex has been employed for the tanning studies, which showed a 10°C increase in shrinkage temperature compared to the self-tanning of the combination system. En ligne : https://drive.google.com/file/d/1EnrRbplVRxjP2rCeCkFkjrOkM4bnfb2E/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3977 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
005598	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Rapid oxidative dehairing with magnesium peroxide and potassium peroxymonosulfate / Andrew G. Gehring in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CI, N° 9 (09/2006)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CI, N° 9 (09/2006) . - p. 324-329 Titre : Rapid oxidative dehairing with magnesium peroxide and potassium peroxymonosulfate Type de document : texte imprimé Auteurs : Andrew G. Gehring, Auteur ; William N. Marmer, Auteur ; Chad E. Mazenko, Auteur ; Robert L. Dudley, Auteur Année de publication : 2006 Article en page(s) : p. 324-329 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Sodium sulfide is traditionally used to remove hair from animal hides during tanning operations. However, alternatives to sodium sulfide are desired because sodium sulfide is an environmental pollutant that is quickly converted to highly toxic hydrogen sulfide gas if accidentally exposed to acid. In past research, we demonstrated that either alkaline calcium peroxide or alkaline hydrogen peroxide may be used as an effective substitute for concentrated sodium sulfide for rapid dehairing. More recently, we demonstrated the effectiveness of alkaline hydrogen peroxide with potassium cyanate. Here we similarly present alternative oxidative dehairing reagents/conditions, using magnesium peroxide and potassium peroxymonosulfate, which may also find application in either the packing plant or beamhouse. As observed with previously reported rapid dehairing, dehairing often is not thorough, leaving very short stubble. However, residual hair was readily removed with a sodium sulfide sharpening/hairburn, indicating that hair stubble was not immunized by the oxidative treatment. Dehairing reaction conditions that rapidly removed 80% or greater of hair from cattle hide pieces were observed for magnesium peroxide (5%, 15% NaOH, 200% float, 45°C, 8 min, hairburn process) and potassium peroxymonosulfate (5%, 15% NaOH, 200% float, 45°C, 7 min, hairburn process). Leather produced from matched side pieces that were subjected to these oxidative dehairing treatments was determined to take up less chromium yet was tougher than leather produced using conventional hairburn with sodium sulfide. Other physical testing results are also reported. En ligne : https://drive.google.com/file/d/187W3ZURmZXXDSwg5-Ulz-bJ-XteOfmY2/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3991 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
005598	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Effects of stretching and drying rate on the mechanical properties of chrome-free Leather / Cheng-Kung Liu in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CI, N° 9 (09/2006)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CI, N° 9 (09/2006) . - p. 330-336 Titre : Effects of stretching and drying rate on the mechanical properties of chrome-free Leather Type de document : texte imprimé Auteurs : Cheng-Kung Liu, Auteur ; Peter H. Cooke, Auteur ; Nicholas P. Latona, Auteur Année de publication : 2006 Article en page(s) : p. 330-336 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Stretching chrome-free leather tanned with glutaraldehyde during vacuum drying may possibly be the best drying method for this particular type of leather, because it results in an improved area yield and better mechanical properties due to a lower drying temperature. We explored this composite drying method and investigated how drying variables affect the drying rate and mechanical properties of chrome-free leather that was tanned with glutaraldehyde. Using a statistical experimental design, a second order polynomial equation was derived to quantitatively describe the relationship between the drying rate and three major independent variables: drying temperature, stretch %, and drying time. Drying rate models derived from this investigation provide a clear understanding of the drying process for chrome-free leather. The drying constant indicates that chrome free leather dries faster than chrome-tanned leather. These models will help the leather industry estimate the proper drying parameters. Our studies showed that stretch % during vacuum drying is the most significant variable affecting the stiffness and area retention of leather. This research indicated that stretching should not be overdone and the preferable length increase should not be greater than 10%; otherwise poor leather properties may result, such as an elongation less than 40% and toughness index less than 1 En ligne : https://drive.google.com/file/d/1rUVS5gwwTB3xnBOW2ngqSbZsPNOS4qPC/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3992 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
005598	-	Périodique	Bibliothèque principale	Documentaires	Disponible