Dépouillements

Synthesis and urea-loading of a novel biosuperabsorbent polymer based on leather waste / Hu Zaiyin in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 2 (03-04/2015)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 2 (03-04/2015) . - p. 51-57 Titre : Synthesis and urea-loading of a novel biosuperabsorbent polymer based on leather waste Type de document : texte imprimé Auteurs : Hu Zaiyin, Auteur ; Yi Shouhong, Auteur ; Hu Wei, Auteur ; Yuling Tang, Auteur ; Wang Ru, Auteur Année de publication : 2015 Article en page(s) : p. 51-57 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Absorbants et adsorbants Copolymère acide acrylique acrylamide Copolymères -- Synthèse Cuirs et peaux -- Déchets -- Recyclage Greffage (chimie) Humidité -- Absorption:Eau -- Absorption Urée Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In order to develop an eco-friendly polymer, a novel superabsorbent polymer was synthesized by grafting the alkaline hydrolysis product of Leather waste (LW) to a copolymer of acrylic acid (AA) and acrylamide (Afv1)(PLW-g-(AA-co-AM) with microwave method assistance. The morphology of the samples was examined by scanning electron microscopy (SEM). Through a single factor experiment, various factors were explored which may affect the water absorption of such a superabsorbent polymer du ring preparation. The results showed that the optimum technological conditions of synthesizing PLW-g-(AA-co-AM) were : dosage of LW 15wt.% of total monomer mass, cross-linking agent 0.06wt.°/0 of monomer mass, neutralization degree 75%, AA: AM= 6 :1, initiator 0.6wt.% of monomer mass. According to this procedure, the PLW-g-(AA-co-AM) with a water-absorbency of 1191.5g/g and salt-absorbency of 94.4g/g was obtained. The product was used as adsorbant for urea, the urea load rate reached 87.76% when the concentration of urea was 10g/L. Meanwhile, the release of urea from the loaded PLW-g-(AA-co-AM) in deionized water exhibited specific release properties. Note de contenu : - EXPERIMENTAL PROCEDURE : Materials - Swelling measurements : Tea-bag method - Instrumental analysis - RESULTS AND DISCUSSIONS : Optimization of the grafting conditions - Loading and release of urea En ligne : https://drive.google.com/file/d/1PiVWaSmKFsQTY_zL8lgdvGzkXTi9x7V3/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23741 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17138	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Effect of hyaluronic acid on the properties of chrome-tanned leather / M. A. R. Siddique in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 2 (03-04/2015)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 2 (03-04/2015) . - p. 58-69 Titre : Effect of hyaluronic acid on the properties of chrome-tanned leather Type de document : texte imprimé Auteurs : M. A. R. Siddique, Auteur ; A. Paula M. Antunes, Auteur ; Anthony D. Covington, Auteur Année de publication : 2015 Article en page(s) : p. 58-69 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Acide hyaluronique -- Elimination Cuirs et peaux -- Analyse Stabilité hydrothermale Travail de rivière (cuir) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In conventional beamhouse operations, the elimination of hyaluronic acid from hides takes place in the soaking stage in the presence of a neutral salt. The impact of sodium chloride and sodium silicate (sodium metasilicate salt)-cured hides along with green hides were investigated in terms of removal of hyaluronic acid. Throughout beamhouse operations, the opening up of fibre structure was investigated by scanning electron microscope (SEM). The residual hyaluronic acid in hide and pelt samples taken after each beamhouse operation was analysed through bio-chemical analysis assisted by UV-visible spectrophotometry. The interaction of residual hyaluronic acid with chromium (III) was investigated in terms of deposition of chromium(III) in cross-sectional layers of chrome-tanned leather through scanning electron microscope — energy dispersive x-ray spectroscopy (SEM-EDX). The hydrothermal stability of chrome tanned leather was investigated by differential scanning calorimetry (DSC). It was found that sodium chloride can remove hyaluronic acid completely in the soaking operation and facilitate good opening and splitting up of fibre structure, which enables good penetration and fixation of chromium(III) species with the purifier collagen. In contrast, in the absence of a neutral salt, residual hyaluronic acid existed throughout the beamhouse operations which resulted in poor opening and splitting up of fibre bundles and later inhibited the penetration of chromium(Ill) species in cross-sectional layers. As a result, comparatively lower hydrothermal stability was observed. Sodium silicate-cured hides did not provide satisfactory results in terms of removing the hyaluronic acid present in the hide, poor opening and splitting up of fibre structure were observed and residual hyaluronic acid was identified even at pickle stage. As a result, the distribution of chromium(Ill) species at the cross-sectional layers varied widely and poor hydrothermal stability of tanned leather was observed after chrome tanning. Note de contenu : - APPROACH AND METHODOLOGY - EXPERIMENTAL METHODS : Raw materials and sampling - Curing of green hides - Chrome tanning - Chemical analysis for hyaluronic acid - Analysis of the opening up of fibre structure - Analysis of chromium distribution in the leather - Characterization of hydrothermal stability - Curing of green hides - Removal of hyaluronic acid - Opening up of fibre structure - Chromium(III) distribution in the cross-sectional layers of tanned leather (grain to flesh - Hydrothermal stability (shrinkage temperature) of chrome-tanned leather En ligne : https://drive.google.com/file/d/1j-K08EqSzq5G2G1bUGnf1uNHq0iy1z_n/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23742 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17138	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Assessment of carbon contribution to the East Kolkata Wetland ecosystem (Ramsar Site : 1208) by leather producing units of the Calcutta leather complex : Part II / Sudin Pal in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 2 (03-04/2015)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 2 (03-04/2015) . - p. 70-79 Titre : Assessment of carbon contribution to the East Kolkata Wetland ecosystem (Ramsar Site : 1208) by leather producing units of the Calcutta leather complex : Part II Type de document : texte imprimé Auteurs : Sudin Pal, Auteur ; Buddhadeb Chattopadhyay, Auteur ; Subhra Kumar Mukhopadhyay, Auteur Année de publication : 2015 Article en page(s) : p. 70-79 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bilan des émissions de gaz à effets de serre Cuirs et peaux -- Industrie -- Inde Dioxyde de carbone Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : ln the context of addition of carbon to East Kolkata Wetland (EKW) ecosystem, an attempt has been made to provide a comprehensive computation of carbon input by raw hides-skins and different chemicals ; and carbon output by various solid and liquid waste from the leather industry. The calculations are based on the conventional operations of nine tanneries of which three produce bag leather, three gloves and three shoe uppers. The amount of carbon that enters into the leather industry depends upon the selection of raw hides and skins, percentage of chemicals used and purity of chemicals. In case of bag leather and shoe upper manufacturing units the carbon value changes depending on the tannery specific finishing recipe, spray types and number of mats. Besides this the carbon value also changes with the customerfs required finish. Whereas the carbon value of solid and liquid wastes changes depending upon the carbon input, mechanical operations and the binding of chemicals with hides and skins. The analysis of large samples from nine selected tanneries has permitted us to calculate that 396.1 ± 11.67kg carbon are present in one tonne raw catie hides or skins. The processing of this one tonne caille raw hides and skins results in 65.54 t 13.06kg carbon being incorporated with chemicals and, from which 320.75 ± 16.37kg of carbon are discharged in the EKW area through different solid and liquid wastes. The tannery agglomerates at the Calcutta Tannery Complex at Bantala, Kolkata are situated on the boundary of the EKW, a Flamsar site, and sa this work is thought to be important to assess the carbon-budget of the EKW ecosystem. En ligne : https://drive.google.com/file/d/11Aom5PWXk90trk2XyRQD5hDlRulnxAzT/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23743 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17138	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Bovine demodicosis : leather from the raw material to the finished product / Mukhtar Taha Abu-Samra in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 2 (03-04/2015)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 2 (03-04/2015) . - p. 80-90 Titre : Bovine demodicosis : leather from the raw material to the finished product Type de document : texte imprimé Auteurs : Mukhtar Taha Abu-Samra, Auteur ; Yassir Adam Shuaib, Auteur Année de publication : 2015 Article en page(s) : p. 80-90 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Analyse Cuirs et peaux de bovins Démodécie Parasitoses Peau -- Maladies chez les animaux Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Demodex bovis mites and associated bacteria produced lesions ranging from 25 to 3618 per hide. Infected hides were compared to non-infected ones, from the raw material to the finished product. Infected hides showed the following defects: (1) Severely infected hides were green-graded as rejects. (2) The curing time was longer than non-infected ones. (3) The rate of water absorption was reduced by more than 50% (4) Liming resulted in dark blue precipitate on the lesions due to uneven distribution of the sulphide. (5) Scudding was very difficult. (6) Deliming and pickling resulted in circuler white blemishes on the grain surface. (7) Slipping-off of the grain surface over severely infected areas. (8) The degree of plumping was only 12-22%. (9) Splitting was very difficult, and when split, holes and cavities were evident. (10) Shaving resulted in detachment of all the lesions on the flash side leaving numerous pits and holes. (11) The aesthetic appeal and cutting areas of the leather were markedly reduced. (12) Severely infected hides were difficult to finish, required more effort in buffing and utilized more dye without producing a drastic improvement in acceptability, and the grain surface was unsightly, uneven, full of elevations and depressions. Leather sections revealed ragged cavities with no definite boundaries. The fibres round those cavities were distorted, thinner than normal and compressed. The grain of the leather showed many small shallow depressions and separation of the grain surface from the corium in areas with large lesions. Severely affected leather showed complete damage and distortion of bath the grain surface and corium. Bovine demodicosis infected hides resulted in a significant reduction at (p<0.01) in the cure-index, tensile strength, tearing load, percentage elongation, correlation coefficient of tensile strength versus tearing load, apparent density, flexing endurance, distension at grain crack, hide substance, moisture, fat and ash contents compared to non-infected ones. However, the distension at grain burst of infected specimens showed a significant reduction at (p<0.05) over non-infected ones. The deleterious effects of bovine demodicosis revealed in this study ; would definitely culminate in serious economic losses in the national economy of the Sudan. The government, veterinarians and research workers should devote more time to the prevention and control of the disease. They should create awareness of the cattle owners regarding the damaging effects of demodectic mange in the quallty of cattle hides, animal health and production. Tanneries should avoid selecting infected bides, involving unnecessary expenditure on the production of otherwise reject finished product because the deleterious effects of this disease persists in any leather goods manufactured from the leather produced. Note de contenu : - MATERIALS AND METHODS : Animals - Laboratory investigations - Preparation of crust leather - Physical tests of crust leather - Chemical analysis of crust leather - Statistical analysis - RESULTS : Findings recorded during the preparation of crust leather - Microscopic examination of crust leather - Physical testing and chemical analysis of crust leather En ligne : https://drive.google.com/file/d/1AvBEdjQ-mMyMPNZpdCzY4-WsK4rfGKY8/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23744 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17138	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Stabilization of collagen by cross-linking with a ferrous-gluconic acid compound / Yang Mao in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 2 (03-04/2015)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 2 (03-04/2015) . - p. 91-94 Titre : Stabilization of collagen by cross-linking with a ferrous-gluconic acid compound Type de document : texte imprimé Auteurs : Yang Mao, Auteur ; Meng Yang, Auteur ; Shan Zhihua, Auteur ; Hongliang Zhu, Auteur ; Chen Hui, Auteur Année de publication : 2015 Article en page(s) : p. 91-94 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Collagène -- Stabilité Gluconique, Acide L'acide gluconique (C6H12O7) est un acide très répandu aussi bien chez les animaux que dans les plantes. Il est le plus souvent intégré dans une molécule plus grande comme c'est le cas dans diverses gommes. Il est obtenu à partir de la gomme d'acacia, à partir de laquelle on l'isole sous la forme de cristaux en aiguilles fondant à 165 °C. Il est soluble dans l'eau et l'alcool. Il est autorisé en Europe comme additif alimentaire (E5748). Réticulation (polymérisation) Stabilité thermique Sulfate de fer Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The stabilization of type I collagen is important to applications of collagen protein. In this paper, the stabilization of type I collagen with Fe-gluconic acid has been studied by various methods such as UV-vis and IR spectra, CD and DSC etc. Gluconic acid can form a compound with ferrous sulphate which can improve the thermal stability of type I collagen to an extent greater than that of Fe atone. The reaction molar ratio was 1:3 between Fe and gluconic acid. The increase of thermal stability is owed to cross-link formation between the compound and collagen. Note de contenu : - MATERIALS AND METHODS : Materiasl - Preparation of the ferrous-gluconic acid compound - UV-Vis spectra - FT-IR spectra - Elemental analysis - Viscosity measurements - Circular dichroism spectropolarimetry - Differential scanning calorimetry (DSC) - RESULTS AND DISCUSSION : UV-vis spectral studies - IR studies - Elemental analysis - Viscosity analysis of collagen-Fe-gluconic acid system - CD studies - DSC studies En ligne : https://drive.google.com/file/d/1c2YGlN8nKFP1Sllk9rvbveFNHT5ENQiM/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23745 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
17138	-	Périodique	Bibliothèque principale	Documentaires	Disponible