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Analytical control of leather fat by near infrared reflectance spectroscopy / H. Iturriaga in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 47-51 Titre : Analytical control of leather fat by near infrared reflectance spectroscopy Type de document : texte imprimé Auteurs : H. Iturriaga, Auteur ; S. Maspoch, Auteur ; Trinitat Canals, Auteur ; D. Rey, Auteur Année de publication : 2007 Article en page(s) : p. 47-51 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bains de trempe -- Analyse Bains de trempe -- Teneur en matières grasses Cuirs et peaux de bovins Etalonnage Extraction par solvant Spectroscopie de réflectance Wet-blue (tannage) Peau tannée au chrome (le chrome donne une couleur bleue) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : A highly expeditious method for the direct analytical control of leather fat as an alternative to the officially endorsed methods was developed based on solvent extraction. The proposed method uses multivariate calibration with partial least-squares regression (PLSR) of diffuse reflectance spectra (NIRRS) for leather specimens. The reference values of the calibration matrix are used to derive those for powdered leather extracted with methylene chloride using the official method. Two different approaches based on matrices containing spectral information for powdered leather and spectra directly recorded on unpowdered leather samples were developed. The optimum calibration model for powdered samples is based on the second spectral derivative and 3 PLS components, and provides overall relative calibration and prediction errors in the region of 5%. On the other hand, the optimum prediction model uses the first spectral derivative and 5 PLS components; the results are similarly as good as those of the calibration model, but the prediction of some external samples results in larger errors arising from the inability to construct calibration sets encompassing the whole variability of the prediction set. Fibre optic-based NIR spectroscopy in combination with multivariate calibration appears to be an effective alternative to existing methods for the analysis and control of fat in the leather tanning industry as it is a rapid method and uses no reagents. Note de contenu : - EXPERIMENTAL PROCEDURES : Leather and fat-liquoring - Samples - Apparatus and software - Recording of NIR spectra - Processing of data - RESULTS AND DISCUSSION : Powdered sample method - Direct recording method - Table 1 : Fat content in the fat-liquoring baths and values provided by the reference method (RM) - Table 2 : Relative standard errors for the calibration and prediction sets as calculated using various calibration models for the powdered (p) and unpowdered (l) samples - Table 3 : Fat content in each calibration and external prediction sample as determined using both methods (p and l) En ligne : https://drive.google.com/file/d/1jRdhYSyPRuG-TxoFtUWG6VS8NNillbld/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39032 [article]

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Removal of Cr(VI) by emulsion membrane technology / Liu Anjun in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 52-58 Titre : Removal of Cr(VI) by emulsion membrane technology Type de document : texte imprimé Auteurs : Liu Anjun, Auteur ; Ding Shaolan, Auteur ; Zhao Chuanchuan, Auteur ; Ren Huijun, Auteur ; Zhao Quanyong, Auteur Année de publication : 2007 Article en page(s) : p. 52-58 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chrome hexavalent Cuirs et peaux -- Industrie Déchets industriels -- Elimination Eaux usées -- Epuration Emulsification Extraction (chimie) Membrane liquide en émulsion pH -- Mesure Surfactants Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : This article describes our study on the removal of Cr(VI) with the emulsion membrane formed from trioctylamine, secondary capryl alcohol and tributyl phosphate as carriers, Span-80 and Lan-113 as surfactants, and kerosene as the membrane solvent. Further, we have performed an orthogonal experiment regarding the carriers, surfactants for individual use and in combination. We also determined the way in which operational conditions, such as Roi, Rew, the internal and external phase pH values, emulsification mixing speed, time and waste/emulsion mixing rate affected the removal rate of Cr(VI). Note de contenu : - EXPERIMENTAL PROCEDURES : Reagents, instruments and equipment - RESULTS AND DISCUSSION : Selection and determination of the emulsion liquid membrane system - Carriers - Extracting mechanism of extractants - Surfactant concentration and types - Liquid volume rate in emulsion liquid (Voil/Vwi) - oil internal ratio Roi - Emulsification stirring speed and time - Extraction stirring/rotating speed - Extraction time - External phase pH values - NaOH concentration of internal water phase - Vw/o/Vwe - - Table 1 : L27(313) orthoganol experimental design - the factors and levels table - Table 2 : L18(37) orthoganol experimental design - the factors and levels table - Table 3 : L25(56) orthoganol experimental design - the factors and levels table En ligne : This article describes our study on the removal of Cr(VI) with the emulsion memb [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39033 [article]

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Gaseous efficiency of methane fermentation of chromium-free tannery wastes / M. Urbaniak in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 59-62 Titre : Gaseous efficiency of methane fermentation of chromium-free tannery wastes Type de document : texte imprimé Auteurs : M. Urbaniak, Auteur Année de publication : 2007 Article en page(s) : p. 59-62 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biodégradation Boues d'épuration Cuirs et peaux -- Industrie Fermentation Mélange Méthane Tannage -- Déchets Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The aim of the research was the neutralisation of particularly environmentally nasty chromium-free tannery wastes by their use for gas making. Methane fermentation of wastes with the addition of excessive sludge from municipal sewage has been carried out. It has been found that, more gas with a higher methane content is obtained from the fermentation of tannery wastes than from the fermentation of municipal sewage sludge. Gaseous efficiency of the fermentation of tannery wastes varies between 950 – 1120dm3 per 1kg of decomposed organic dry substance. Gas obtained from fermentation of these tannery wastes may contain over 70% of methane. The biodegradability of chromium-free tannery wastes in the methane fermentation process may additionally be increased by means of thermal treatment applied before fermentation. Note de contenu : - EXPERIMENTAL PROCEDURES : Analytical tests - Materials - Procedures - DISCUSSION OF RESULTS : Possible industrial benefits - Table 1 : Materials prepared for fermentation and post-fermentation mixtures obtained after 10 days fermentation En ligne : https://drive.google.com/drive/folders/1s-_z15S5jTWCU6O-yOgZT8wOxOwbzS-G?usp=sha [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39034 [article]

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Evaluating combinations of leather fungicides by inhibition zone / Gu Haibin in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 63-68 Titre : Evaluating combinations of leather fungicides by inhibition zone Type de document : texte imprimé Auteurs : Gu Haibin, Auteur ; Changqing Zhao, Auteur ; Wuyong Chen, Auteur ; Yan Li, Auteur Année de publication : 2007 Article en page(s) : p. 63-68 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Conservation Fongicides Inhibition microbienne Synergie Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : synergism index (SI, Formula (1)) and graphical method (Fig. 1) expressed by the minimum inhibitory concentrations (MIC) are often used to evaluate the type of action of combined leather fungicides. The determination of MIC is a complicated and time-consuming process and the exact value is difficult to determine, so a rapid, simple method would be useful to evaluate synergistic combinations. In this study, a formula of the synergism index (SI*, Formula (3)) and the graphical method (Fig. 3) expressed by the diameters of inhibition zones were defined. (2-thiocyanoethyl)-cinnamate (A) and a commercial product of Isothiazoline whose active ingredients are the mixture 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (B) were chosen for combination, and the diameters of inhibition zones and minimum inhibitory concentrations for the effectiveness of different combinations to nine fungi were determined to verify the feasibility of the two methods. Results show that the values of SI calculated by MIC and the value of SI* calculated by diameters of inhibition zones are only slightly different, but they both show the same tendency in that, to most fungi and for most proportions, the values of SI and SI* are all less than 1.0. So, the different combinations of A and B show a synergistic effect or additive effect and the method of SI* is viable to evaluate their action. The relation between the value of SI* and the type of action is same as that of SI. Regarding the graphical method, the results for MIC show a dramatic synergistic effect that is different from that of SI method, and the results of evaluation of diameters of inhibition zones is similar to that of SI* method. So the graphical method expressed by the diameters of inhibition zones is also usable. As the determination of inhibition zones is a relative simple process, the two new methods are very convenient for evaluating synergistic combinations of leather fungicides. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Preparation off ungal spore suspensions - Preparation ofme dium containing fungal spores - Evaluation ofaction type by crossed filter paper strip - Mensuration ofdiam eter ofinhibit ion zone - Determination ofminim um inhibitory concentration (MIC) - RESULTS AND DISCUSSION : Evaluation by crossed filter paper strip - Evaluation by synergism index - Evaluation ofacti on type by the graphical method En ligne : https://drive.google.com/file/d/1wYcVNUB_nVyO6LGAkIDktar9D2dydMan/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39035 [article]

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Inhibiting lipolytic haloarchaeal damage on brine cured hide with halocin producer strains / Meral Birbir in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 69-72 Titre : Inhibiting lipolytic haloarchaeal damage on brine cured hide with halocin producer strains Type de document : texte imprimé Auteurs : Meral Birbir, Auteur ; S. Erylmaz, Auteur Année de publication : 2007 Article en page(s) : p. 69-72 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bactériocines Les bactériocines sont une famille de peptides ou protéines synthétisés naturellement par certaines bactéries. Une bactériocine consiste généralement en un composé protéique de 20 à 60 acides aminés. Les bactériocines ne sont pas des antibiotiques mais elles possèdent des propriétés antibiotiques : - Elles peuvent être bactériocides, c'est-à-dire éliminer certains micro-organismes. - Elles peuvent être bactériostatiques, c'est-à-dire inhiber la croissance de certains micro-organismes. Cuirs et peaux -- Conservation Inhibition microbienne Lipases Les lipases sont des enzymes hydrosolubles capables d'effectuer l'hydrolyse de fonctions esters et sont spécialisées dans la transformation de triglycéride en glycérol et en acides gras (lipolyse). À ce titre, elles constituent une sous-classe des estérases. Lipolyse Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The Kaldırım and Kayacık Salterns of Tuz Lake in Central Anatolia are the main salt sources of Turkey. 55% of the salt requirements of Turkey is supplied from these salterns. 492 000 and 620 000 tons of salt were produced from Kaldırım and Kayacık Salterns in 2004, respectively. Crude salt extracted from these salt sources is commonly used in hide preservation. Lipolytic extremely halophilic Archaea found in the salt may reduce hide quality. Therefore, a microbial survey was conducted to examine lipolytic activities of the strains isolated from Kaldırım and Kayacık Salterns and determine whether or not halocins which were produced by the strains of Kaldırım and Kayacık Salterns may be used to inhibit lipolytic haloarchaeal strains in brine solutions. The levels of lipase producer strains in the both salterns was found to be almost similar. 39% of Kaldırım Saltern’s strains and 43% of Kayacık Saltern’s strains produced lipase. 89% of Kaldırım Saltern’s strains and 29% of Kayacık Saltern’s strains produced halocins effective against each other. It was found that lipase negative halocin producers of both Kaldırım and Kayacık Salterns were able to inhibit lipase positive strains in these salterns. Hence, it is recommended that lipase negative halocin producers or their halocin extracts may be used in preventing the haloarchaeal deterioration that can occur during brine curing of hides when using crude salt from whatever source. Note de contenu : - Growth conditions of extremely halophilic strains - Lipase activity - Halocin activity - Table 1 : Lipase activities and sensitivities of Kaldırım Saltern strains against Kaldırım Saltern halocin producers - Table 2 : Lipase activities and sensitivities of Kayacık Saltern strains against Kayacık Saltern halocin producers En ligne : https://drive.google.com/file/d/1Vt2v6Xm7xD0XM_JcJjeaNYf6-EoS025q/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39036 [article]

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Aliphatic anionic polyurethane microemulsion leather filling-retanning agent / Bao Lihong in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 91, N° 2 (03-04/2007)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 91, N° 2 (03-04/2007) . - p. 73-80 Titre : Aliphatic anionic polyurethane microemulsion leather filling-retanning agent Type de document : texte imprimé Auteurs : Bao Lihong, Auteur ; Lan Yunjun, Auteur ; Shufen Zhang, Auteur Année de publication : 2007 Article en page(s) : p. 73-80 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Agents de tannage Caractérisation Charges (matériaux) Chimie analytique Cuirs et peaux -- Propriétés mécaniques Cuirs et peaux -- Propriétés organoleptiques Cuirs et peaux -- Propriétés physiques Formulation (Génie chimique) Imperméabilisation Microémulsions Poids moléculaires Polymères aliphatiques Polyuréthanes Retannage Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The retanning process plays an important role in optimizing the leather’s colour, levelness, softness, fullness, and hydrophobicity. Polymer retanning agents are important materials for this process. The present study used maleic anhydride modified castor oil (MCO), PEG1000 (polyethylene glycol) and IPDI (isophorone diisocyanate) as main materials to synthesize polyurethane microemulsions (MC-PURs) and employed them to retan chrometanned leathers. The hydroxyl functionality of MCO was investigated by chemical and 1HNMR analysis, and confirmed to be about 2.0. The chemical structures of MCO, prepolymer and MC-PUR were characterized by IR. The optimized synthesis formulation and polyurethane microemulsion MC-PUR3 for MC-PURs as retanning agent was selected by comparing the properties of retanned leathers, such as softness, fullness, grain tightness, tensile strength, extension at break, depth of shade, waterproof properties et al. Then, MC-PUR3 was characterized by means of DSC, TG/DTG and TEM techniques. SEM microgram of MC-PUR3 retanned leather shows that the fibres are well dispersed. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Preparation of maleic anhydride modified castor oil (MCO) - Preparation of microemulsions of polyurethane filling retanning agents (MC-PURs) - Determination of molecular weight - H n.m.r. spectroscopy - Purification - FT-IR spectroscopy - Differential scanning spectroscopy - Thermo-gravimetric analysis - Transmission electron microscope analysis - Measurement of final dyebath exhaustion - Physical and waterproofness properties of leathers - Organoleptic properties of the final leathers - Scanning electron microscopic analysis - RESULTS AND DISCUSSION : Determination of the average molecular weight, hydroxyl number and average hydroxyl functionality (Fn(OH)) of MCO - Determination of the average hydroxyl functionality of MCO by chemical analysis - Determination of the average hydroxyl functionality of MCO by 1HNMR - Chemical structure analysis by IR - OPTIMIZATION OF RETANNING AGENT : Effect of MCO/PEG1000 mass ratio on the properties of retanned leathers - Effect of carboxyl content of MC-PUR on the properties of retanned leathers - Effect of NCO/OH molar ratio on the properties of retanned leathers - Thermal properties of MC-PUR3 - Table 1 : Basic formulations of MC-PURs - Table 2 : Filling, retanning and wet finishing processes - Table 3 : Effect of MCO/PEG1000 mass ratio on the properties of retanned leathers - Table 4 : Effect of carboxyl content of MC-PUR on the properties of retanned leathers - Table 5 : Effect of NCO/OH molar ratio on the properties of retanned leathers En ligne : https://drive.google.com/file/d/19ti2BicD3kfHFF4Z4QLX1cSWPC0J39gs/view?usp=share [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39037 [article]

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