Dépouillements

Polycaprolactone strengthening keratin/bioactive glass composite scaffolds with double cross-linking networks for potential application in bone repair / Liying Sun in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 13 p. Titre : Polycaprolactone strengthening keratin/bioactive glass composite scaffolds with double cross-linking networks for potential application in bone repair Type de document : texte imprimé Auteurs : Liying Sun, Auteur ; Shan Li, Auteur ; Kaifeng Yang, Auteur ; Junchao Wang, Auteur ; Zhengjun Li, Auteur ; Nianhua Dan, Auteur Année de publication : 2022 Article en page(s) : 13 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Composites Ingénierie tissulaire kératines La kératine est une protéine, synthétisée et utilisée par de nombreux êtres vivants comme élément de structure, et également l'exemple-type de protéine fibreuse. La kératine est insoluble, et peut être retrouvée sur l'épiderme de certains animaux, notamment les mammifères, ce qui leur garantit une peau imperméable. Parfois, lors d'une friction trop importante, la kératine se développe à la surface de la peau formant une callosité. Les cellules qui produisent la kératine meurent et sont remplacées continuellement. Les morceaux de kératine qui restent emprisonnés dans les cheveux sont couramment appelés des pellicules. La molécule de kératine est hélicoïdale et fibreuse, elle s'enroule autour d'autres molécules de kératine pour former des filaments intermédiaires. Ces protéines contiennent un haut taux d'acides aminés à base de soufre, principalement la cystéine, qui forment un pont disulfure entre les molécules, conférant sa rigidité à l'ensemble. La chevelure humaine est constituée à 14 % de cystéine. Il y a deux principales formes de kératines : l'alpha-kératine, ou α-keratin, présente chez les mammifères notamment, dont l'humain, et la bêta-kératine, ou β-keratin, que l'on retrouve chez les reptiles et les oiseaux. Ces deux types de kératines ne présentent clairement pas d'homologie de séquence. Chez l'être humain, la kératine est fabriquée par les kératinocytes, cellules se trouvant dans la couche profonde de l'épiderme. Les kératinocytes absorbent la mélanine (pigment fabriqué par les mélanocytes), se colorent et ainsi cette pigmentation de l'épiderme permet de protéger les kératinocytes des rayons ultraviolets du Soleil. (Wikipedia) Poly-e-caprolactone Polymères en médecine Régénération (biologie) Réticulation (polymérisation) Tissu osseux Verre Index. décimale : 668.9 Polymères Résumé : In this study, we aimed at constructing polycaprolactone (PCL) reinforced keratin/bioactive glass composite scaffolds with a double cross-linking network structure for potential bone repair application. Thus, the PCL-keratin-BG composite scaffold was prepared by using keratin extracted from wool as main organic component and bioactive glass (BG) as main inorganic component, through both cross-linking systems, such as the thiol-ene click reaction between abundant sulfhydryl groups of keratin and the unsaturated double bond of 3-methacryloxy propyltrimethoxy silane (MPTS), and the amino-epoxy reaction between amino groups of keratin and the epoxy group in (3-glycidoxymethyl) methyldiethoxysilane (GPTMS) molecule, along with introduction of PCL as a reinforcing agent. The success of the thiol-ene reaction was verified by the FTIR and 1H-NMR analyses. And the structure of keratin-BG and PCL-keratin-BG composite scaffolds were studied and compared by the FTIR and XRD characterization, which indicated the successful preparation of the PCL-keratin-BG composite scaffold. In addition, the SEM observation, and contact angle and water absorption rate measurements demonstrated that the PCL-keratin-BG composite scaffold has interconnected porous structure, appropriate pore size and good hydrophilicity, which is helpful to cell adhesion, differentiation and proliferation. Importantly, compression experiments showed that, when compared with the keratin-BG composite scaffold, the PCL-keratin-BG composite scaffold increased greatly from 0.91 ± 0.06 MPa and 7.25 ± 1.7 MPa to 1.58 ± 0.21 MPa and 14.14 ± 1.95 MPa, respectively, which suggesting the strong reinforcement of polycaprolactone. In addition, the biomineralization experiment and MTT assay indicated that the PCL-keratin-BG scaffold has good mineralization ability and no-cytotoxicity, which can promote cell adhesion, proliferation and growth. Therefore, the results suggested that the PCL-keratin-BG composite scaffold has the potential as a candidate for application in bone regeneration field. Note de contenu : - MATERIALS AND METHODS : Materials - Fabrication of keratin-BG and PCL-keratin-BG composite scaffolds CHARACTERIZATION : Analyses of chemical structure - Morphology observation and porosity detection of scaffolds - Hydrophilicity testing - Mechanical properties - In vitro biological activity evaluation - Statistical analysis - RESULTS AND DISCUSSION : Characterization of chemical structure - Porous morphology of keratin-BG and PCL-keratin-BG scaffolds - Hydrophilicity of scaffolds - Mechanical properties - In vitro mineralization characterization - Biocompatibility–cell viability assay - Table 1 : The radio of calcium to phosphorus (Ca/P) of HA after mineralization in keratin-BG and PCL-keratin-BG scaffolds DOI : https://doi.org/10.1186/s42825-021-00077-w En ligne : https://link.springer.com/content/pdf/10.1186/s42825-021-00077-w.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37565 [article]

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Toxicity evaluation of collagen hydrolysates from chrome shavings and their potential use in the preparation of amino acid fertilizer for crop growth / Li Zhao in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 23 p. Titre : Toxicity evaluation of collagen hydrolysates from chrome shavings and their potential use in the preparation of amino acid fertilizer for crop growth Type de document : texte imprimé Auteurs : Li Zhao, Auteur ; Shengdong Mu, Auteur ; Weixiang Wang, Auteur ; Gu Haibin, Auteur Année de publication : 2022 Article en page(s) : 23 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Acides aminés Les acides aminés (ou aminoacides) sont une classe de composés chimiques possédant deux groupes fonctionnels : à la fois un groupe carboxyle –COOH et un groupe amine –NH2. Parmi ceux-ci, les acides α-aminés se définissent par le fait que leur groupe amine est lié à l'atome de carbone adjacent au groupe acide carboxylique (le carbone α), ce qui leur confère la structure générique H2N–CHR–COOH, où R représente la chaîne latérale, qui identifie l'acide α-aminé. Les acides α-aminés jouent un rôle fondamental en biochimie comme constituants élémentaires des protéines : ils polymérisent en formant des liaisons peptidiques qui aboutissent à de longues chaînes macromoléculaires appelées peptides. Analyse toxicologique Chrome Collagène -- Analyse Engrais organiques Evaluation Hydrolysat de collagène Poisson zèbre Solubilité Tests de toxicité Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Resource utilization of chrome shavings (CS) has attracted a lot of attention from scientists and technologists in leather industry. Especially, the collagen hydrolysates extracted from CS are expected to find potential application values in agricultural field. However, there is no biotoxicity analysis of collagen hydrolysates from CS. Herein, the collagen hydrolysates with different molecular weights were produced from CS by three hydrolysis dechroming methods including alkaline hydrolysis, enzymatic hydrolysis and alkaline-enzymatic synergistic hydrolysis, and the optimal hydrolysis process of CS was designed and conducted. To evaluate their toxicity, the three collagen hydrolysates were formulated into a nutrient solution for zebrafish development. The obtained results indicated that the hydrolysates with low concentrations (less than 0.6 mg/mL) were safe and could promote the development for zebrafish embryos. Furthermore, the three collagen hydrolysates were utilized as organic nitrogen sources and formulated into amino acid water-soluble fertilizers (AAWSF) including alkaline type fertilizer (OH), enzymatic type fertilizer (M) and alkaline-enzymatic type fertilizer (OH–M) for the early soilless seeding cultivation of wheat, soybean and rapeseed. It is worth mentioning that the chromium contents in the prepared AAWSF were less than 10 mg/kg, which is far less than the limit value in the standard (China, 50 mg/kg). The growth and development of seedlings (germination rate, plant height, fresh weight of leaves, soluble sugar content and chlorophyll content) were investigated. The corresponding results showed that the growth of seedlings watered with AAWSF was better compared with the other treatments, and the OH–M fertilizer had the best promoting effect on the seedlings growth and development, followed by the M and OH fertilizers. The safe toxicity assessment of the collagen hydrolysates will expand their application scope, and the use of collagen hydrolysates extracted from CS for seedlings growth also provides an effective and reasonable way to deal with the chromium-containing leather solid waste, which is an effective way to realize its resource utilization. Note de contenu : - EXPERIMENTAL : Materials - Preparation of collagen hydrolysate - Analysis of collagen hydrolysate - Zebrafish husbandry and embryos collection - Embryonic acute toxicity test - Preparation of AAWSF - Analysis of AAWSF - Crops seeding and growth experiments - Growth determination of seedlings - RESULTS AND DISCUSSION : Preparation of collagen hydrolysate - Analysis of collagen hydrolysates - Mortality, hatchability and medial lethal concentration of zebrafish embryos - Morphological development and deformity of zebrafish embryos - Body length and cardiomyogenesis of zebrafish embryos - General analysis of amino acid water-soluble fertilizer (AAWSF) - Effect of different AAWSF on the macroscopical growth of various seedlings - Effect of different AAWSF on the contents of Cr, N, P and K, chlorophyll and soluble sugar in seedlings - Table 1 : The pH value, protein and ash contents of ACH, ECH and AECH - Table 2 : The content of heavy metal in ACH, ECH and AECH - Table 3 : Amino acid composition of ACH, ECH and AECH DOI : https://doi.org/10.1186/s42825-021-00072-1 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-021-00072-1.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37566 [article]

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Effect of cationic monomer structure on the aggregation behavior of amphoteric acrylic polymer around isoelectric point / Qijun Li in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 9 p. Titre : Effect of cationic monomer structure on the aggregation behavior of amphoteric acrylic polymer around isoelectric point Type de document : texte imprimé Auteurs : Qijun Li, Auteur ; Yudan Yi, Auteur ; Ya-Nan Wang, Auteur ; Jing Li, Auteur ; Bi Shi, Auteur Année de publication : 2022 Article en page(s) : 9 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation Composés amphotériques Monomères cationiques Point isoélectrique En biochimie, le point isoélectrique (pI) ou potentiel hydrogène isoélectrique (pHI) est le pH auquel une molécule est sous forme d'ion mixte ou, en physico-chimie, le pH d'une solution aqueuse dans laquelle un solide existe sous un potentiel électrique neutre. En physico-chimie : Selon Bolger, le caractère acide ou basique d'une surface s'exprime par son point isoélectrique " Is ou IEPS (Iso Electric point for the surface) " ou point de charge nulle " PCN ou PZC (Point of Zero Charge) ", défini comme étant le pH de la solution aqueuse dans laquelle le solide existe sous un potentiel électrique neutre. Si le pH de la solution est basique, la surface est acide, et inversement. La différence entre le PZC et l'IEPS est basée sur le phénomène d'adsorption spécifique. On peut considérer que si la grandeur mesurée ne dépend pas de la solution utilisée pour la mesurer (pH, concentration, nature des ions), alors on a affaire à un PZC. Dans le cas contraire, c'est un IEPS que l'on mesure. Par exemple, quand la mesure de goutte sessile à deux liquides est utilisée, on considère en général qu'il n'y a pas adsorption des ions de cette goutte et que la goutte déplace complètement l'alcane qui sert de deuxième liquide: on est alors en présence d’un PZC. Au contraire, dans les mesures de potentiel d'écoulement (streaming potential), la solution joue un rôle important et c'est un IEPS que l'on mesure. Enfin, la charge nette se définit grâce au pH de la solution aqueuse dans laquelle la surface métallique existe, dans un état électriquement neutre (c’est-à-dire [M-OH2+ surf]=[M-O- surf]) et au PZC. - Si pH < PZC alors la charge nette est positive - Si pH > PZC alors la charge nette est négative. Il existe plusieurs méthodes expérimentales permettant de décrire l’état acido-basique de la surface : la mesure du potentiel d’écoulement, la photoélectrochimie, la mesure de l’angle de contact, et la spectroscopie XPS. Polyacryliques Précipitation (chimie) Retannage Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Amphoteric polymer can be used as retanning agent in leather manufacture. It is particularly useful in chrome-free tanning systems since it can regulate the charge properties of chrome-free leather and enhance the fixation of anionic post-tanning chemicals in leather. However, the aggregation and precipitation of amphoteric polymer retanning agents around the isoelectric point (pI) hinder their wide application. Herein, we synthesized five amphoteric acrylic polymers (AAPs) by free radical copolymerization with acrylic acid and five different cationic acrylic monomers. The effect of cationic monomer structure on the aggregation behavior of AAPs was investigated. The aggregation of AAPs in aqueous solution showed pH and concentration dependence. Light scattering analysis showed that Poly (AA-co-MAPTAC) and Poly (AA-co-DMAPMA) were in the shape of coiled linear flexible chains with small particle size (Rg 7.6 nm and 14.8 nm, respectively) near the pI. However, Poly (AA-co-DAC), Poly (AA-co-DMC) and Poly (AA-co-DMAEMA) were in the shape of hollow spheres and exhibited serious aggregation. Quantum chemical calculations suggested that the amide groups in the cationic monomers MAPTAC and DMAPMA enhanced the nucleophilicity of AAPs. Thus the corresponding AAPs could carry a large number of cationic charges to slow their aggregation when the pH just climbed over the pI. The results are expected to provide theoretical reference for the synthesis and widespread application of AAPs. Note de contenu : - EXPERIMENTAL : Materials - Preparation of AAPs - FT-IR analysis - 13C NMR analysis - SEC analysis - Isoelectric point (pI) and particle size determination - Turbidity measurement - DLS/SLS analysis - DWS analysis - Cationic degree determination - Quantum chemical calculations - RESULTS AND DISCUSSION : Structural characterization of AAPs - Molecular weight and pI of AAPs - Effect of pH on the aggregation behavior of AAPs - Effect of concentration on the aggregation behavior of AAPs - DLS/SLS analysis - DWS analysis - Analysis on the charge-carrying ability of AAPs - Table 1 : Molecular weight and pI of AAPs - Table 2 : Light Scattering Parameters of AAPs - Table 3 : Zeta potentials of AAPs near the pI - Table 4 : Quantum chemical calculations of molecular models of AAPs DOI : https://doi.org/10.1186/s42825-022-00078-3 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00078-3.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37572 [article]

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Bletilla striata polysaccharide modified collagen fiber composite sponge with rapid hemostasis function / Xingyu Yan in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 15 p. Titre : Bletilla striata polysaccharide modified collagen fiber composite sponge with rapid hemostasis function Type de document : texte imprimé Auteurs : Xingyu Yan, Auteur ; Yining Chen, Auteur ; Weihua Dan, Auteur ; Nianhua Dan, Auteur ; Zhengjun Li, Auteur Année de publication : 2022 Article en page(s) : 15 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biopolymères Caractérisation Collagène Composites à fibres Polymères en médecine Polysaccharides microbiens Index. décimale : 668.9 Polymères Résumé : Emergencies often result in uncontrollable bleeding, which is thought to be the leading cause of death at the scene of the injured. Among various hemostasis scenarios, collagen fiber (CF) is gradually replacing traditional hemostatic materials due to its superior properties and ease of sourcing from animals. Herein, we use CF and the natural herbaceous Bletilla striata as raw materials to prepare a collagen fiber-oxidized Bletilla striata composite hemostatic sponge (CFOB). During the cross-linking process, the triple helix structure of collagen stays intact, and its porous three-dimensional network structure brings excellent bulkiness and water absorption properties. Experiments show that the optimal amount of sponge CFOB-10, namely oxidized Bletilla striata polysaccharide 0.5 mg/mL and CF 5 mg/mL, only needed 25 ± 4.06 s for hemostasis time in the rat liver hemorrhage model. In addition, CFOB meets the safety performance requirements of cytotoxicity classification standard 0. Therefore, the optimal amount of CFOB is an excellent new hemostatic material with application potential. Note de contenu : - EXPERIMENTS AND METHODS : Experimental instruments and equipment - Main reagents and materials - Preparation method - Characterization method - RESULTS : FT-IR spectra measurements - CD spectral analysis - Differential scanning calorimetry (DSC) - AFM and SEM - Determination of water absorption and porosity ratio - Hemolysis assay - Activated partially thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) - Evaluation of cell compatibility - Whole-blood clotting assay (CT) - Blood clotting assay in vitro - Evaluation of in vivo hemostatic performance - Analysis of coagulation mechanism and synergy DOI : https://doi.org/10.1186/s42825-022-00079-2 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00079-2.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37573 [article]

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Diagnosing the environmental impacts of typical fatliquors in leather manufacture from life cycle assessment perspective / Yue Yu in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 14 p. Titre : Diagnosing the environmental impacts of typical fatliquors in leather manufacture from life cycle assessment perspective Type de document : texte imprimé Auteurs : Yue Yu, Auteur ; Qingyong Sun, Auteur ; Yunhang Zeng, Auteur ; Yirui Lin, Auteur ; Ya-Nan Wang, Auteur ; Bi Shi, Auteur Année de publication : 2022 Article en page(s) : 14 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Industrie -- Aspect de l'environnement Durée de vie (Ingénierie) Environnement -- Etudes d'impact Produits de nourriture du cuir Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The environmental impacts of typical fatliquors were diagnosed by the life cycle assessment of industrial production and use (post-tanning) processes. Life cycle impact assessment and sensitivity analysis showed that fatliquor and fatliquoring operation were the major contributors to the environmental impacts of post-tanning because a large amount of fatliquors was consumed during fatliquoring operation. The environmental impacts of fatliquors decreased in the following order: chlorinated paraffin (CP) > sulfonated rape oil (SNR) > sulfated rape oil (SR) > phosphated rape oil (PR) > oxidized–sulfited rape oil (OSR). Sulfuric acid, fuming sulfuric acid, and chlorine used for fatliquor modification gave the main contribution to most impact categories for SR, SNR, and CP production, whereas rape oil contributed the most for PR and OSR production. OSR use process reduced the primary energy demand, abiotic depletion potential, and global warming potential by 38.5%, 56.0%, and 48.5%, respectively, compared with CP use process. These results suggested that biomass-derived fatliquors, especially oxidized–sulfited and phosphate modified fatiliquors, helped reduce the environmental burdens in leather manufacturing. Note de contenu : - MATERIALS AND METHODS : Materials - Goal and scope definition - Functional unit and system boundary - Life cycle inventory analysis - LCIA - Sensitivity and uncertainty analyses - RESULTS AND DISCUSSION : Environmental impacts of fatliquor production process - Environmental impacts of fatliquor use process - Sensitivity and uncertainty analyses - Table 1 Description of impact categories - Table 2 Sensitivities of chemicals, energy, and effluents to impact categories for various fatliquor use processes DOI : https://doi.org/10.1186/s42825-022-00084-5 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00084-5.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37574 [article]

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Deep learning and machine learning neural network approaches for multi class leather texture defect classification and segmentation / Praveen Kumar Moganam in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 21 p. Titre : Deep learning and machine learning neural network approaches for multi class leather texture defect classification and segmentation Type de document : texte imprimé Auteurs : Praveen Kumar Moganam, Auteur ; Denis Ashok Sathia Seelan, Auteur Année de publication : 2022 Article en page(s) : 21 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Apprentissage automatique L'apprentissage automatique (en anglais : machine learning, litt. "apprentissage machine"), apprentissage artificiel ou apprentissage statistique est un champ d'étude de l'intelligence artificielle qui se fonde sur des approches mathématiques et statistiques pour donner aux ordinateurs la capacité d'"apprendre" à partir de données, c'est-à-dire d'améliorer leurs performances à résoudre des tâches sans être explicitement programmés pour chacune. Plus largement, il concerne la conception, l'analyse, l'optimisation, le développement et l'implémentation de telles méthodes. (Wikipedia) Cuirs et peaux -- Défauts Détection de défauts (Ingénierie) Réseaux neuronaux (informatique) Tags : 'Réseaux  de  neurones  à  convolution'  'Classificateur  d'apprentissage  automatique'  'Défauts  du  cuir'  'Classement  multi-classes'  'Carte  d'activation  classe'  Segmentation Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Modern leather industries are focused on producing high quality leather products for sustaining the market competitiveness. However, various leather defects are introduced during various stages of manufacturing process such as material handling, tanning and dyeing. Manual inspection of leather surfaces is subjective and inconsistent in nature; hence machine vision systems have been widely adopted for the automated inspection of leather defects. It is necessary develop suitable image processing algorithms for localize leather defects such as folding marks, growth marks, grain off, loose grain, and pinhole due to the ambiguous texture pattern and tiny nature in the localized regions of the leather. This paper presents deep learning neural network-based approach for automatic localization and classification of leather defects using a machine vision system. In this work, popular convolutional neural networks are trained using leather images of different leather defects and a class activation mapping technique is followed to locate the region of interest for the class of leather defect. Convolution neural networks such as Google net, Squeeze-net, RestNet are found to provide better accuracy of classification as compared with the state-of-the-art neural network architectures and the results are presented. Note de contenu : - MACHINE VISION-BASED LEATHER INSPECTION SYSTEM : Leather Image acquisition - Leather texture defects - DEEP LEARNING NEURAL NETWORK APPROACH FOR CLASSIFICATION AND LOCALIZATION OF LEATHER DEFECTS : Leather image Data Set preparation and preprocessing - Deep learning convolutional neural network architectures - Visualization of region of interest for defect localization - MACHINE LEARNING BASED APPROACHES FOR MULTI CLASS DEFECT CLASSIFICATION OF LEATHER DEFECTS : Hand crafted Feature extraction from leather images - Shallow feed-forward neural network-based machine learning classifier - PERFORMANCE METRICS OF DEEP LEARNING AND MACHINE LEARNING CLASSIFIERS - RESULTS AND DISCUSSION : Feature maps of convolution neural networks - Feature extraction using GLCM, autocorrelation - Training and testing performance of deep learning neural networks Training performance of shallow feed forward neural network classifier - Classification performance of deep learning neural networks - Classification performance of machine learning approaches - Class activation maps for selection of region of interest in leather images DOI : https://doi.org/10.1186/s42825-022-00080-9 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00080-9.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37575 [article]

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Methods for determination of plasticizer migration from polyvinyl chloride synthetic materials : a mini review / Yi Chen in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 10 p. Titre : Methods for determination of plasticizer migration from polyvinyl chloride synthetic materials : a mini review Type de document : texte imprimé Auteurs : Yi Chen, Auteur ; Shuai Zhou, Auteur ; Siyu Pan, Auteur ; Dongfang Zhao, Auteur ; Jianshe Wei, Auteur ; Minzhong Zhao, Auteur ; Haojun Fan, Auteur Année de publication : 2022 Article en page(s) : 10 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chlorure de polyvinyle Cuir Essais (technologie) Evaporation Exsudation Extraction (chimie) Plastifiants Produits chimiques -- Migration Index. décimale : 668.9 Polymères Résumé : Plasticizer migration is responsible for premature coating failure in polyvinyl chloride (PVC) synthetic materials that continue to benefit our daily life as a reliable and cost-efficient simulant of genuine leather. In this context, the establishment of standard assays that measure the migration rate of plasticizers under varying scenarios plays a pivotal role in comparing durability of those PVC-derived leather-simulants. In this review, multiple methodologies developed over the last decade for determining plasticizer migration from PVC coating are compiled, with their operational principles, merits, and limitations being taken into consideration along with specific apparatus required for each. A concluding section discusses current challenges in this field, and highlights how nuclear magnetic resonance and computational simulation surpass conventional assays in yielding intercomparable results, and hence screening migration-resistant plasticizers in a labor- and time-saving way. Since migration resistance represents a decisive performance indicator of plasticizers, this systematic review may provide guidance to quite a few practitioners in PVC synthetic material industry, who are now engaged in validating various sustainable alternatives with performance allegedly equal to conventional but toxic di-(2-ethylhexyl) phthalate plasticizer. Note de contenu : - Test methods for plasticizer migration : Test methods for plasticizer volatilization - Test methods for plasticizer exudation - Test methods for plasticizer extraction - Table 1 : Methods currently available for determination of plasticizer migration from PVC synthetic materials DOI : https://doi.org/10.1186/s42825-022-00081-8 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00081-8.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37576 [article]

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Tannery wastewater treatment : conventional and promising processes, an updated 20-year review / Jun Zhao in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 22 p. Titre : Tannery wastewater treatment : conventional and promising processes, an updated 20-year review Type de document : texte imprimé Auteurs : Jun Zhao, Auteur ; Qinglian Wu, Auteur ; Yuling Tang, Auteur ; Jianfei Zhou, Auteur ; Hongguang Guo, Auteur Année de publication : 2022 Article en page(s) : 22 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Adsorption Coagulation Cuirs et peaux -- Industrie -- Aspect de l'environnement Eau -- Epuration -- Traitement biologique Eaux usées -- Analyse Eaux usées -- Décontamination Eaux usées -- Recyclage Electrochimie Filtration Floculation Oxydation Tannage Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Mismanagement of various wastes especially waste water produced by tanning processes has caused serious environmental problems and ultimately impaired human health. Constant efforts have been making to alleviate the pollution of tannery wastewater (TWW), yet terminal treatment still takes dominance. In this review, research on TWW treatment from 2000 to 2021 was summarized, and main methods such as coagulation and flocculation, adsorption, biological treatment, membrane filtration, advanced oxidation process were briefly discussed. More detailed introduction was given to the method of electrochemical treatment since it has excellent performance such as environmental friendliness and high efficiency, hence attracting more and more research attention in recent years. In view of the harsh physi-chemical conditions of TWW, integrated or combined treatment methods are accordingly recommended with better performance and multi-function, however comprehensive studies on optimization of methods combination and cost-effectiveness are needed. The certain issues that the residue Cr in treatment sludge and high salinity in effluent still remain were put forward in this work and potential solutions were provided. Moreover, this review proposed the perspective that realizing multi-function, recycling, and intensification should be the developing direction for future TWW treatment. This review is expected to provide a general guide for researchers who aspire to ameliorate TWW pollution problems and understand various methods utilized in this field. Note de contenu : - CHARACTERISTICS OF TANNERY WASTEWATER - TREATMENT FOR TANNERY WASTEWATER : Flocculation and coagulation - Biological treatment - Membrane filtration - Advanced oxidation processes - Electrochemical treatment - Adsorption - Integrated methods - PROBLEMS TO BE SOLVED AND POTENTIAL SOLUTIONS - TWW TREATMENT FOR THE FUTURE - Table 1 Direct discharge standard of treated TWW in different countries - Table 2 Qualitative comparisons of all TWW treatment methods - Table 3 Selected reports (2010–2020) related to combined/integrated methods to treat real or synthetic TWW DOI : https://doi.org/10.1186/s42825-022-00082-7 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00082-7.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37577 [article]

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Recent strategies of collagen-based biomaterials for cartilage repair : from structure cognition to function endowment / Xiaoyue Yu in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 23 p. Titre : Recent strategies of collagen-based biomaterials for cartilage repair : from structure cognition to function endowment Type de document : texte imprimé Auteurs : Xiaoyue Yu, Auteur ; Haiping Zhang, Auteur ; Yiliang Miao, Auteur ; Shanbai Xiong, Auteur ; Yang Hu, Auteur Année de publication : 2022 Article en page(s) : 23 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biopolymères Cartilage Collagène Ingénierie tissulaire Polymères en médecine Régénération (biologie) Index. décimale : 668.9 Polymères Résumé : Collagen, characteristic in biomimetic composition and hierarchical structure, boasts a huge potential in repairing cartilage defect due to its extraordinary bioactivities and regulated physicochemical properties, such as low immunogenicity, biocompatibility and controllable degradation, which promotes the cell adhesion, migration and proliferation. Therefore, collagen-based biomaterial has been explored as porous scaffolds or functional coatings in cell-free scaffold and tissue engineering strategy for cartilage repairing. Among those forming technologies, freeze-dry is frequently used with special modifications while 3D-printing and electrospinning serve as the structure-controller in a more precise way. Besides, appropriate cross-linking treatment and incorporation with bioactive substance generally help the collagen-based biomaterials to meet the physicochemical requirement in the defect site and strengthen the repairing performance. Furthermore, comprehensive evaluations on the repair effects of biomaterials are sorted out in terms of in vitro, in vivo and clinical assessments, focusing on the morphology observation, characteristic production and critical gene expression. Finally, the challenge of biomaterial-based therapy for cartilage defect repairing was summarized, which is, the adaption to the highly complex structure and functional difference of cartilage. Note de contenu : - STRUCTURE AND DEFECTS OF CARTILAGE : The composition of articular cartilage - Hierarchical structure of articular cartilage - The etiology and degree of cartilage defect - Current repair strategies - - STRUCTURE AND FUNCTION OF COLLAGEN : Hierarchical structure of COL I - The role of COL I in cartilage repair - DESIGN AND PREPARATION OF COLLAGEN-BASED BIOMATERIALS FOR CARTILAGE DEFECT REPAIR : Forming and cross-linking of collagen-based biomaterials - Incorporated fabrication of collagen-based biomaterials for cartilage repair - COMPREHENSIVE EVALUATIONS OF CARTILAGE REPAIR BY COLLAGEN-BASED BIOMATERIALS : Physicochemical properties - Bioactivities for cartilage repair - Clinical diagnosis - Table 1 : General methods used to evaluate the bioactivities of biomaterials DOI : https://doi.org/10.1186/s42825-022-00085-4 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00085-4.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37578 [article]

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The dynamic characteristics of the center of pressure for toe-out gait : implications for footwear design / Bo Li in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 9 p. Titre : The dynamic characteristics of the center of pressure for toe-out gait : implications for footwear design Type de document : texte imprimé Auteurs : Bo Li, Auteur ; Xianyi Zhang, Auteur Année de publication : 2022 Article en page(s) : 9 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Marche Tags : Pincement  'Centre  de  pression'  Marche  Rapidité Index. décimale : 685.3 Chaussures Résumé : - Background : Toe-out gait is often used as a conservative technique to reduce knee adduction moment, which has been targeted to modify knee osteoarthritis progression. The center of pressure (COP) can not only be used to evaluate gait stability, but is also more reliable and practical than local plantar pressures as it does not depend on accurate foot zone divisions. However, to the authors’ knowledge, few study has reported the influence of the foot progression angle on the dynamic characteristics of the COP. - Research question : The aim of the study was to investigate the effects of the deliberately toe-out gait on the COP trajectory and stability during walking in healthy individuals. - Methods : Thirty healthy young adults were asked to walk along an 8-m walkway. A Footscan 1 m pressure plate was used to measure the center of pressure during walking. - Results : Compared to the normal gait, the COP of the toe-out gait shifted laterally during the initial contact phase, and shifted laterally and anteriorly during the forefoot contact phase. The mean anterior–posterior velocity of COP reduced by 0.109 m/s during the foot flat phase and the duration of the foot flat phase and forefoot push off phase increased by 4.5% and reduced by 7.0%, respectively. - Significance : Compared to the normal gait, the findings of this study suggest that biomechanical alteration of foot under our experimental conditions may decrease gait stability and increase forefoot load during toe-out walking. The situation may be improved by well-designed footwear or custom-made insole and the biomechanics analysis method can be used to test the efficacy of therapeutic footwear or insole for individuals with deliberately toe-out walking. Note de contenu : - Participants - Materials and apparatus - Procedures - Data analysis - Table 1 Comparison of ML-COP deviation and velocity between toe-out and normal gait - Table 2 Comparison of AP-COP deviation and velocity between toe-out and normal gait - Table 3 Time comparisons between toe-out and normal gait DOI : https://doi.org/10.1186/s42825-022-00088-1 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00088-1.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37579 [article]

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Efficient and ecological leather processing : replacement of lime and sulphide with dispase assisted by 1-allyl-3-methylimidazolium chloride / Hui Liu in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 13 p. Titre : Efficient and ecological leather processing : replacement of lime and sulphide with dispase assisted by 1-allyl-3-methylimidazolium chloride Type de document : texte imprimé Auteurs : Hui Liu, Auteur ; Keyong Tang, Auteur ; Xiumin Li, Auteur ; Jie Liu, Auteur ; Xuejing Zheng, Auteur ; Ying Pei, Auteur Année de publication : 2022 Article en page(s) : 13 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chaux Sulfurée Chlorure de 1-allyl-3-méthylimidazolium Cuirs et peaux -- Industrie -- Aspect de l'environnement Cuirs et peaux -- Propriétés physiques Cuirs et peaux de bovins Dispase est une protéase qui clive la fibronectine , le collagène IV et dans une moindre mesure le collagène I. Elle se trouve dans certaines bactéries et peut être isolée à partir de filtrats de culture de Bacillus polymyxa . Il peut être extrait, purifié et utilisé dans la recherche. Il peut être particulièrement utile de séparer les épithéliums embryonnaires et le mésenchyme . La Dispase II est spécifique du clivage des liaisons leucine - phénylalanine . La Dispase est souvent utilisée pour digérer les cellules primaires adhérentes en culture, car ce traitement s'est avéré plus doux que la digestion à la trypsine. (Wikipedia) Eaux usées -- Analyse Epilage Produits chimiques -- Suppression ou remplacement Ressources renouvelables Stabilité hydrothermale Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 system used in unhairing and fiber opening has given rise to the pollution to the environment. It is necessary to develop substitute technology for the Na2S/Ca(OH)2. In the present study, 1-allyl-3-methylimidazolium chloride ([AMIm]Cl) was used to cooperate with dispase for cycle unhairing and one-pot beamhouse to recycle waste bovine hides and compared with conventional processing. During those processes, the mechanism of [AMIm]Cl-dispase synergistic unhairing and collagen fibers opening were studied. Besides, plant hazard, organic matter and [AMIm]Cl of wastewater from [AMIm]Cl-dispase process were respectively investigated and separated to evaluate the environmental and economic benefits of the [AMIm]Cl-dispase process. As a result, enzyme activity after unhairing by [AMIm]Cl-diapase system for using 5 times is higher than that by KCl-dispase system, and needs lower unhairing time, which is because of rapid penetration of [AMIm]Cl-dispase solution in bovine hides. For this reason, the tensile strength and elastic modulus of tanned leather from [AMIm]Cl-dispase process are higher than those from the KCl-diapase and conventional processes, and its hydrothermal shrinkage temperature is comparable to that of the conventional one. Because of the 58.13% lower wastewater discharge (WD), 66.60% lower total solids (TS), 97.23% lower ammonia nitrogen (NH3-N), non-toxic wastewater and organic matter recovery in wastewater are reached from [AMIm]Cl-dispase process, which is expected to be an alternative to the conventional process to reduce environmental pollution and realize the sustainable development of technology for leather manufacturing. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Experimental and conventional processes - Investigation of the dispase penetration by FITC - Organic matter and saline solution separation in wastewater - The harm of wastewater to plant growth - RESULTS AND DISCUSSION : Effect of [AMIm]Cl-dispase synergistic cycle unhairing - Effect of [AMIm]Cl-dispase ecological beamhouse - Hydrolysis of interfibrillar substance in hides - Distribution of dispase - Mechanism of one-pot beamhouse and recovery of organic matter in wastewater - Grain morphology and collagen fibers aggregation structure of tanned leathers - Physical and hydrothermal properties of tanned leather - Environmental and economic benefits Table 1 : Physical properties and hydrothermal stability of tanned leathers from conventional (C), KCl-dispase (KCl/D) and [AMIm]Cl-dispase ([AMIm]Cl/D) processes - Table 2 : Pollutant loads and wastewater discharge (WD) from different methods (unit: kg/t of raw hide) DOI : https://doi.org/10.1186/s42825-022-00086-3 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00086-3.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37580 [article]

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Self-driven directional dehydration enabled eco-friendly manufacture of chrome-free leather / Yawen Huang in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 12 p. Titre : Self-driven directional dehydration enabled eco-friendly manufacture of chrome-free leather Type de document : texte imprimé Auteurs : Yawen Huang, Auteur ; Hanzhong Xiao, Auteur ; Haoliang Pu, Auteur ; Ni Xue, Auteur ; Baicun Hao, Auteur ; Xin Huang, Auteur ; Bi Shi, Auteur Année de publication : 2022 Article en page(s) : 12 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Alcool Caractérisation Déshydratation Peaux brutes -- Teneur en eau Tannage chrome free Zéolites Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Manufacture of eco-friendly chrome-free leather is of great significance for realizing sustainable development of leather industry. Conventional tanning theory believes that it is impossible to convert raw hide to leather without the utilization of cross-linking agent (e.g., chrome salts) among collagen fibers in raw hide. Here, we developed a brand-new leather manufacture strategy that relied on the composite dehydration media enabled self-driven directional dehydration mechanism to accomplish chrome-free leather manufacture for the first time, rather than followed the classic cross-linking mechanism that has been obeyed for more than one century in leather industry. We demonstrated that the essence of leather making is to regulate the water content in raw hide rather than to form cross-linkage among collagen fibers. The composite dehydration media comprised of anhydrous ethanol and molecular sieves (3A activated zeolite powder) successfully guaranteed continuous self-driven directional dehydration of raw hide by establishing stable water concentration gradient between raw hide and ethanol, which significantly increased the dispersity of collagen fibers in raw hide (with the water content reduced from 56.07% to 5.20%), thus obtaining chrome-free leather that is more ecological than chrome-tanned leather due to the elimination of any tanning agent. The as-prepared chrome-free leather exhibited outstanding tear force (174.86 N), tensile strength (24.56 N mm−2), elongation at break (53.28%) and dry-thermal stability, superior to chrome-tanned leather. Notably, the used composite dehydration media was recyclable for chrome-free leather manufacture, therefore facilitating an environmentally benign leather manufacture process. Our investigations are expected to open up a new conceptual leather making strategy that is applicable for realizing substantial manufacture of eco-friendly leather. Note de contenu : - Materials - Preparation of eco-friendly chrome-free leather - Dehydration of raw hide using anhydrous ethanol - Preparation of chrome-tanned leather - Selective adsorption of 3A activated zeolite powder to water from the water-ethanol mixture - Characterization DOI : https://doi.org/10.1186/s42825-022-00089-0 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00089-0.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37582 [article]

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Extraction of a novel tanning agent from indigenous plant bark and its application in leather processing / Raju Kumar Das in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 15 p. Titre : Extraction of a novel tanning agent from indigenous plant bark and its application in leather processing Type de document : texte imprimé Auteurs : Raju Kumar Das, Auteur ; Al-Mizan, Auteur ; Fatema Tuj Zohra, Auteur ; Sobur Ahmed, Auteur ; Khondoker Shahin Ahmed, Auteur ; Hemayet Hossain, Auteur Année de publication : 2022 Article en page(s) : 15 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Agents de tannage Cuirs et peaux de chèvres Extraction par solvant Retannage Tanins -- analyse Tanins végétaux Tannage chrome free Tannage végétal Température de retrait Xylocarpus granatum Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made to extract vegetable tannins from Xylocarpus granatum bark using different solvents (e.g., water, methanol, ethanol, and chloroform) and compare with conventional vegetable tanning agents such as mimosa and quebracho. The highest extraction efficiency was observed 31.22% by methanol. The presence of tannin content and polyphenolic compounds, e.g. (-)epicatechin (503 mg/100 g dry extract), catechin hydrate (218 mg/100 g dry extract), catechol (29 mg/100 g dry extract) were ensured by UV–Vis, FT-IR spectroscopy and HPLC. Again, condensed tannins, moisture content, and pH of the methanol extracted tannin were found 47.80%, 5.82%, and 3.97 respectively. The leather tanned by Xylocarpus granatum tannin showed a shrinkage temperature of 86.34 ± 1.52 °C. Other properties such as tensile strength, tear strength, grain cracking load, and distention at grain cracking were comparable to conventional vegetable-tanned leather. The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy (SEM) which revealed a compact structure of the leather fibers. In light of the findings from the study, X. granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry. Note de contenu : - MATERIALS AND METHODS : Materials - Methods - Determination of the properties of X. granatum tanned leather - RESULTS AND DISCUSSION : Extraction efficiency of X. granatum tannin by different solvents - Composition of extracted tanning material - Qualitative identification of X. granatum tannin - Chemical structure of X. granatum tannin - Tanning performances of X. granatum tannin - Table 1 : Tanning, and retanning process of goat skin - Table 2 : pH, moisture content of the extracted sample, and standard tanning materials (Mean ± SD) - Table 3 : Chemical tests for the presence of tannin in Xylocarpus granatum extracted sample - Table 4 : Total tannin content and condensed tannin of Mimosa, Quebracho and Xylocarpus granatum - Table 5 : Physical–mechanical properties of leather tanned by conventional and extracted tannin (mean ± SD) DOI : https://doi.org/10.1186/s42825-022-00092-5 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00092-5.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38214 [article]

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Technical and technological constraints facing Tanzania leather value chain : a snapshot of intervention measures / Cecilia Rolence China in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 12 p. Titre : Technical and technological constraints facing Tanzania leather value chain : a snapshot of intervention measures Type de document : texte imprimé Auteurs : Cecilia Rolence China, Auteur ; Rahel Elibariki, Auteur ; Jamal Msami, Auteur ; Stephen Mwombela, Auteur ; Lugano Wilson, Auteur Année de publication : 2022 Article en page(s) : 12 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chaîne de valeur La chaîne de valeur est l'ensemble des étapes déterminant la capacité d'un domaine d'activité stratégique (DAS), d'une entreprise ou d'une organisation à obtenir un avantage concurrentiel. Ces étapes correspondent aux services de l'entreprise ou, de manière arbitraire, aux activités complexes imbriquées qui constituent l'organisation. Cuirs et peaux -- Industrie et commerce -- Tanzanie Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The leather value chain starts with livestock, the key source of hides and skins, and the main raw materials for the industry. Despite having the second-largest livestock population in Africa, Tanzania is only the 11th largest exporter of leather on the continent, underlining the disproportionate contribution of the sector to the economy. This study presents the results of a recent assessment aimed at identifying performance bottlenecks in Tanzania's leather sector. The assessment took place in October–December 2020 and involved 10 tanneries, 30 leather goods factories and 11 service providers/institutions. Findings reveal that 90% of tanneries are dissatisfied with the quality of hides and skins due to brand marks, flay cuts, skin diseases, and inadequate curing. These supply chain bottlenecks are further compounded by skill deficiencies among processors, poor waste management, and limited awareness about laws, policies and regulations governing trade in the sector. At the downstream end of the value chain, the trade in leather and related articles is facing competition from high importation of low-grade products like plastic shoes and second-hand products. This paper recommends that efforts to increase leather's economic and trade value need to focus on upgrading Tanzania’s production, processing, branding and marketing capacities. Note de contenu : - METHODOLOGY : sample size and sampling technique - Data collection - Data analysis - RESULTS AND DISCUSSION : Current status of Tanzania leather value chain - Constraints in the Tanzanian leather value chain - CONCLUSION, RECOMMENDATIONS AND WAY FORWARD DOI : https://doi.org/10.1186/s42825-022-00095-2 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00095-2.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38215 [article]

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Laccase-functionalized magnetic framework composite enabled chlorophenols degradation, a potential remediation for fungicides residues in leather / Min Cao in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 11 p. Titre : Laccase-functionalized magnetic framework composite enabled chlorophenols degradation, a potential remediation for fungicides residues in leather Type de document : texte imprimé Auteurs : Min Cao, Auteur ; Jie Yu, Auteur ; Xing Zhang, Auteur ; Yamei Lin, Auteur ; He Huang, Auteur Année de publication : 2022 Article en page(s) : 11 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chlorophénols Un chlorophénol est un composé aromatique constitué d'un cycle benzénique substitué par un groupe hydroxyle (phénol) et par un ou plusieurs atomes de chlore (chlorobenzène). Les chlorophénols sont produits par halogénation électrophile aromatique du phénol par le dichlore. Le groupe hydroxyle étant orienteur ortho-para (effet -I/+M), on obtient préférentiellement un mélange de 2-chlorophénol et de 4-chlorophénol, puis le 2,4-dichlorophénol et enfin le 2,4,6-trichlorophénol. La tétra- et pentachloration nécessitent la présence d'un catalyseur (AlCl3). La plupart des chlorophénols sont solides à température ambiante ; ils ont un très fort goût et odeur "médical". Les chlorophénols sont couramment utilisés comme pesticides, herbicides et désinfectants. Détérioration enzymatique Fongicides Laccases Les laccases (EC 1.10.3.2) appartiennent à une famille d'enzymes ayant pour cofacteur du cuivre. C'est une oxydase (oxydoréductase, EC 1) que l'on retrouve dans de nombreuses plantes, champignons et micro-organismes. Le cuivre est lié sur plusieurs sites de la protéine. On distingue trois types. Les types 2 et 3 sont appelés grappe tri-nucléaire. Le cuivre du type 1 est soluble dans l'eau. Le mercure déplace le cobalt complexé dans les laccases. Les complexants du cuivre peuvent le déplacer et le remplacer par du cobalt. Les cyanures complexent également le cuivre, mais dans ce cas il n'est pas possible de réinsérer du cobalt. Les laccases oxydent les dérivés phénoliques mais d'une façon ménagée qui transforme la lignine en monolignol. Magnétisme Nanoparticules Nanoparticules -- Synthèse Polluants organiques -- Détérioration Remédiation (technologie) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Chlorophenols, used as the fungicides in leather, are strictly limited in leather products. In this work, a metal–organic framework material, zeolitic metal azolate framework-7 (MAF-7), was first used to encapsulate laccase (Lac) to prepare MAF-7/Lac bio-composites with 98.5% immobilization yield. Afterward, Lac/MNP@MOM was formed by introducing the magnetic nanoparticles (MNPs) into the Lac@MOM. MAF-7 with better hydrophilicity and stronger pH buffering ability, exhibits good compatibility with laccase, which can reserve the activity of laccase after immobilization. Moreover, the porous structure of MAF-7 is favorable for the sufficient contact between laccase and substrates. Lac/MNP@MOM exhibited excellent activity when exposed to high temperature, extreme pH, and organic solvents, which also simplified complex recovery steps. Furthermore, the degradation rate of 2,4-dichlorophenol (2,4-DCP) could reach as high as 97% within 24 h by immobilized laccase, and after nine consecutive cycles of operation, enzyme activity could remain over 80%, which gives it the potential for practical applications. Note de contenu : - EXPERIMENTAL SECTION : Materials - Synthesis method for magnetic nanoparticles (MNPs) - Synthesis method for Lac/MNP@MOM, Lac@MOM, and MAF-7 - Characterization - Laccase activity assay and steady-state kinetic assay - Laccase activity in harsh conditions - Removal of 2,4-dichlorophenol - RESULTS AND DISCUSSION : Characterization of as-prepared composites - Catalytic activity and Michaelis–Menten kinetic parameters of Lac@MOM, and Lac/MNP@MOM - Laccase activity in harsh conditions - Removal of 2,4 -dichlorophenol - Table 1 : Kinetic parameters of free laccase, Lac@MOM, and Lac/MNP@MOM DOI : https://doi.org/10.1186/s42825-022-00094-3 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00094-3.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38216 [article]

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An exploration of enhancing thermal stability of leather by hydrophilicity regulation : effect of hydrophilicity of phenolic syntan / Sun Qingyong in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 10 p. Titre : An exploration of enhancing thermal stability of leather by hydrophilicity regulation : effect of hydrophilicity of phenolic syntan Type de document : texte imprimé Auteurs : Sun Qingyong, Auteur ; Zeng Yunhang, Auteur ; Yue Yu, Auteur ; Ya-Nan Wang, Auteur ; Bi Shi, Auteur Année de publication : 2022 Article en page(s) : 10 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Analyse Cuirs et peaux -- Teneur en eau Dynamique moléculaire Hydrophobie Phénoplastes Retannage Simulation, Méthode de Stabilité thermique Syntans Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Effect of retanning on the thermal stability of leather is eliciting increasing attention. However, the relationship between the hydrophilicity of retanning agents and the heat resistance of leather and the corresponding mechanism remain unclear. Herein, phenolic formaldehyde syntans (PFSs) were selected as models to explore the effect of the hydrophilicity of retanning agents on the thermal stability of retanned leather. The thermal stability of leather was closely correlated to the hydrophilic group content (sulfonation degree) of PFSs. As the sulfonation degree increased, the water absorption rate of PFSs and their retanned leathers decreased, whereas the thermal stability of leather increased. Molecular dynamics simulation results proved that the introduction of PFSs could reduce the binding ability of collagen molecules with water and thus decreased the water molecules around the PFS-treated collagen. These results may provide guidance for the tanners to select retanning agents reasonably to improve the thermal stability of leather. Note de contenu : - EXPERIMENTAL : Materials - Water adsorption behavior of PFSs - Retanning experiments - Analysis of leather - MD simulation - RESULTS AND DISCUSSION : Effect of DS on the water adsorption behavior of PFSs - Effect of DS on the water adsorption of PFSs retanned leather - Effect of DS on the thermal stability of PFSs retanned leathers - Table 1 : Retanning and fatliquoring processes - Table 2 : Sequence of the collagen peptide used for constructing collagen model - Table 3 : Simulation details - Table 4 : Adsorption kinetics parameters fitted by the pseudo-second-order rate model - Table 5 : Weight loss of PFSs retanned leathers and control leather at different stages and residual weight DOI : https://doi.org/10.1186/s42825-022-00096-1 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00096-1.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38217 [article]

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A review on room-temperature self-healing polyurethane : synthesis, self-healing mechanism and application / Yupeng Li in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 22 p. Titre : A review on room-temperature self-healing polyurethane : synthesis, self-healing mechanism and application Type de document : texte imprimé Auteurs : Yupeng Li, Auteur ; Yong Jin, Auteur ; Fan Wuhou, Auteur ; Rong Zhou, Auteur Année de publication : 2022 Article en page(s) : 22 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Polymères -- Synthèse Polymères autoréparants Polyuréthanes Index. décimale : 668.9 Polymères Résumé : Polyurethanes have been widely used in many fields due to their remarkable features such as excellent mechanical strength, good abrasion resistance, toughness, low temperature flexibility, etc. In recent years, room-temperature self-healing polyurethanes have been attracting broad and growing interest because under mild conditions, room-temperature self-healing polyurethanes can repair damages, thereby extending their lifetimes and reducing maintenance costs. In this paper, the recent advances of room-temperature self-healing polyurethanes based on dynamic covalent bonds, noncovalent bonds and combined dual or triple dynamic bonds are reviewed, focusing on their synthesis methods and self-healing mechanisms, and their mechanical properties, healing efficiency and healing time are also described in detial. In addition, the latest applications of room-temperature self-healing polyurethanes in the fields of leather coatings, photoluminescence materials, flexible electronics and biomaterials are summarized. Finally, the current challenges and future development directions of the room-temprature self-healing polyurethanes are highlighted. Overall, this review is expected to provide a valuable reference for the prosperous development of room-temperature self-healing polyurethanes. Note de contenu : - DYNAMIC COVALENT BONDS : Disulfide, diselenide, and detelluride bonds - Imine bonds - Boroxine bonds - Alkoxyamine bonds - DYNAMIC NONCOVALENT BONDS : Multiple hydrogen bonds - Metal–ligand coordination bonds - Ionic bonds - COMBINED DUAL OR TRIPLE DYNAMIC BOND SYSTEMS - CURRENT APPLICATIONS OF ROOM-TEMPERATURE SELF-HEALING POLYURETHANES : Leather coatings - Photoluminescence materials - Flexible electronics - Biomaterials - Table 1 : Types and self-healing mechanisms of main dynamic covalent bonds for room temperature self-healing polyurethanes - Table 2 : Types and self-healing mechanisms of main dynamic noncovalent bonds for room-temperature self-healing polyurethanes - Table 3 : Summary of the healing mechanisms, mechanical properties, healing time and healing efficiency of room-temperature self-healing polyurethanes DOI : https://doi.org/10.1186/s42825-022-00097-0 En ligne : https://link.springer.com/content/pdf/10.1186/s428 Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38218 [article]

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Essential role of isoelectric point of skin/leather in leather processing / Ya-Nan Wang in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 3 p. Titre : Essential role of isoelectric point of skin/leather in leather processing Type de document : texte imprimé Auteurs : Ya-Nan Wang, Auteur ; Longyu Hu, Auteur Année de publication : 2022 Article en page(s) : 3 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Collagène Cuirs et peaux Point isoélectrique En biochimie, le point isoélectrique (pI) ou potentiel hydrogène isoélectrique (pHI) est le pH auquel une molécule est sous forme d'ion mixte ou, en physico-chimie, le pH d'une solution aqueuse dans laquelle un solide existe sous un potentiel électrique neutre. En physico-chimie : Selon Bolger, le caractère acide ou basique d'une surface s'exprime par son point isoélectrique " Is ou IEPS (Iso Electric point for the surface) " ou point de charge nulle " PCN ou PZC (Point of Zero Charge) ", défini comme étant le pH de la solution aqueuse dans laquelle le solide existe sous un potentiel électrique neutre. Si le pH de la solution est basique, la surface est acide, et inversement. La différence entre le PZC et l'IEPS est basée sur le phénomène d'adsorption spécifique. On peut considérer que si la grandeur mesurée ne dépend pas de la solution utilisée pour la mesurer (pH, concentration, nature des ions), alors on a affaire à un PZC. Dans le cas contraire, c'est un IEPS que l'on mesure. Par exemple, quand la mesure de goutte sessile à deux liquides est utilisée, on considère en général qu'il n'y a pas adsorption des ions de cette goutte et que la goutte déplace complètement l'alcane qui sert de deuxième liquide: on est alors en présence d’un PZC. Au contraire, dans les mesures de potentiel d'écoulement (streaming potential), la solution joue un rôle important et c'est un IEPS que l'on mesure. Enfin, la charge nette se définit grâce au pH de la solution aqueuse dans laquelle la surface métallique existe, dans un état électriquement neutre (c’est-à-dire [M-OH2+ surf]=[M-O- surf]) et au PZC. - Si pH < PZC alors la charge nette est positive - Si pH > PZC alors la charge nette est négative. Il existe plusieurs méthodes expérimentales permettant de décrire l’état acido-basique de la surface : la mesure du potentiel d’écoulement, la photoélectrochimie, la mesure de l’angle de contact, et la spectroscopie XPS. Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Leather, made from animal hide or skin, is mainly composed of collagen. Collagen is a type of fibrous protein. The basic amino acid residues (lysine, arginine and histidine) and acidic amino acid residues (glutamic acid and aspartic acid) of the protein confer zwitterionic character to collagen, making the protein positively or negatively charged at different pH values. The pH at which the net charge of collagen becomes zero is defined as isoelectric point (IEP, the value is labeled as pI). DOI : https://doi.org/10.1186/s42825-022-00099-y En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00099-y.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38219 [article]

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The improvement of dispersity, thermal stability and mechanical properties of collagen fibers by silane modification : an exploration for developing new leather making technology / Shuangfeng Xu in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 11 p. Titre : The improvement of dispersity, thermal stability and mechanical properties of collagen fibers by silane modification : an exploration for developing new leather making technology Type de document : texte imprimé Auteurs : Shuangfeng Xu, Auteur ; Hanzhong Xiao, Auteur ; Bi Shi, Auteur Année de publication : 2022 Article en page(s) : 11 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation Collagène Cuirs et peaux Procédés de fabrication Réaction de couplage Silanes Stabilité thermique Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The effect of hydrophobic modification on the performances of collagen fibers (CFs) was investigated by using silane coupling agents with different alkyl chains as hydrophobic modifiers. It was found silane could be easily grafted onto CF surface through covalent bonds under 5% water content. This modification led to the transformation of surface wettability of CF from hydrophilic to hydrophobic. Interestingly, the change of surface wettability resulted in substantial improvement of the modified CF properties, presenting well dispersity of collagen fibers, higher thermal stability and enhanced mechanical properties in comparison with natural CF. The degree of improvement mainly depended on the length of alkyl chain in silane. Longer alkyl chain produced strong hydrophobicity and subsequently more superior performances of the modified CF. When the length of alkyl chain increased to 18 carbon atoms, the modified CF possessed durable superhydrophobicity even exposed to aqueous solutions of different pH, UV, and organic solvents, and had excellent thermal and mechanical properties like leather fibers. In general, this work clearly revealed that the properties of CF are closely and positively related to the hydrophobicity, which is suggestive in developing new leather making technology. Note de contenu : - Materials - Fabrication of dehydrated collagen fibers (CFs) - Fabrication of hydrophobic collagen fibers (TMSx-CF) - Characterization DOI : https://doi.org/10.1186/s42825-022-00100-8 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00100-8.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38220 [article]

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Organosilicon leather coating technology based on carbon peak strategy / Wenkai Wang in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)  

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 11 p. Titre : Organosilicon leather coating technology based on carbon peak strategy Type de document : texte imprimé Auteurs : Wenkai Wang, Auteur ; Haojun Fan, Auteur ; Lijiang Song, Auteur ; Zhenya Wang, Auteur ; Heng Li, Auteur ; Jun Xiang, Auteur ; Qiang Huang, Auteur ; Xiangquan Chen, Auteur Année de publication : 2022 Article en page(s) : 11 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation Cuir synthétique Gaz à effet de serre -- Réduction Polydiméthylsiloxane Le polydiméthylsiloxane —[O-Si(CH3)2]n—, ou poly(diméthylsiloxane) selon la nomenclature systématique, communément appelé PDMS ou diméthicone, est un polymère organominéral de la famille des siloxanes souvent présent dans les shampoings. On l'y ajoute pour augmenter le volume des cheveux mais il peut également aller boucher les pores du cuir chevelu et rendre les cheveux gras. C'est une des raisons pour lesquelles se laver les cheveux tous les jours est très déconseillé avec un shampooing contenant des silicones. Il existe également de l'amodiméthicone, qui est un dérivé du diméthicone. Le polydiméthylsiloxane est un additif alimentaire (E900), utilisé comme antimoussant dans les boissons (Coca-Cola BlāK). La chaîne de poly(diméthylsiloxane) forme également la structure de base des huiles et des caoutchoucs silicones. Revêtements -- Propriétés mécaniques Revêtements organiques Silylation La silylation est l'introduction d'un groupe silyle, généralement substitué (R3Si–), dans une molécule. Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Based on the demand of carbon peak and carbon emission reduction strategy, divinyl-terminated polydimethylsiloxane (ViPDMSVi), poly(methylhydrosiloxane) (PMHS), divinyl-terminated polymethylvinylsiloxane (ViPMVSVi), and fumed silica were used as primary raw materials, polydimethylsiloxane (PDMS) synthetic leather coating was in situ constructed by thermally induced hydrosilylation polymerization on the synthetic leather substrate. The effect of the viscosity of ViPDMSVi, the active hydrogen content of PMHS, the molar ratio of vinyl groups to active hydrogen, the dosage of ViPMVSVi and fumed silica on the performance of PDMS polymer coating, including mechanical properties, cold resistance, flexural resistance, abrasion resistance, hydrophobic and anti-fouling properties were investigated. The results show that ViPDMSVi with high vinyl content and PMHS with low active hydrogen content is more conducive to obtaining organosilicon coating with better mechanical properties, the optimized dosage of ViPMVSVi and fumed silica was 7 wt% and 40 wt%, respectively. In this case, the tensile strength and the broken elongation of the PDMS polymer coating reached 5.96 MPa and 481%, showing reasonable mechanical properties for leather coating. Compared with polyurethane based or polyvinyl chloride based synthetic leather, the silicon based synthetic leather prepared by this method exhibits excellent cold resistance, abrasion resistance, super hydrophobicity, and anti-fouling characteristics. Note de contenu : - EXPERIMENTAL : Materials - Preparation of PDMS synthetic leather - Characterization - RESULTS AND DISCUSSION : FT-IR analysis of PDMS polymer film - Mechanical properties of PDMS polymer coating - Characteristics of PDMS synthetic leather coating - Table 1 : Surface energy and their parameters of the test liquids - Table 2 : Effect of ViPDMSVi viscosity on mechanical properties of PDMS polymer film - Table 3 : Effect of ViPDMSVi mixture with different viscosity on mechanical properties of PDMS polymer film - Table 4 : Effect of active hydrogen content on mechanical properties of PDMS polymer film - Table 5 : Effect of molar ratio of vinyl groups to active hydrogen on mechanical properties of PDMS polymer film - Table 6 : Effect of ViPMVSVi mass fraction on mechanical properties of PDMS polymer film - Table 7 : Effect of fumed silica mass fraction on mechanical properties of PDMS polymer film DOI : https://doi.org/10.1186/s42825-022-00101-7 En ligne : https://link.springer.com/content/pdf/10.1186/s42825-022-00101-7.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38221 [article]

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Optimization and application of UVC irradiation for prevention of fungal biodeterioration of vegetable tanned and chrome tanned leather / Eshita Jhahan in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 4 (Année 2022)

[article]  inJOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 4 (Année 2022) . - 14 p. Titre : Optimization and application of UVC irradiation for prevention of fungal biodeterioration of vegetable tanned and chrome tanned leather Type de document : texte imprimé Auteurs : Eshita Jhahan, Auteur ; Subarna Bhattacharyya, Auteur ; Anirban Chaudhuri, Auteur ; Nirmal Sarkar, Auteur ; Shaheen Akhtar, Auteur ; Punarbasu Chaudhuri, Auteur Année de publication : 2022 Article en page(s) : 14 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Aspergillus Biodégradation Cuir Rayonnement ultraviolet Résistance à la traction Tannage au chrome Tannage végétal Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : UV-C irradiation critically effects the growth of micro-fungi and also deteriorate leather materials. In the present study vegetable tanned and chrome tanned leather were infected with pure cultures of Aspergillus niger and Aspergillus flavus, which were isolated from stored leather materials. UV-C light (λ = 254 nm) was applied on infected leather for 15 and 60 min. The changes in leather qualities were examined through weight, tensile strength, scanning electron microscope, energy dispersive X-ray and Fourier transform infrared spectroscopy study after 15 and 30 days of fungal inoculation. Vegetable tanned leather was more vulnerable in case of fungal attack than chrome tanned leather while A. flavus showed more influence on leather deterioration than A. niger. The results showed that weight loss after 30 days for 15 and 60 min irradiation exposure was 1.3% compared to A. flavus infected leather (3.93%). The tensile strength of vegetable and chrome tanned UV irradiated leather was increased by 44% and 7% respectively. The scanning electron microscopic images exhibit the limited presence of conidiophores in UV-C exposed leather which confirmed the potentiality of irradiation for controlling fungal growth. The infrared spectral analysis of UV-C exposed infected leather samples showed neither shifting of wavenumber nor displacement of any functional groups. Altogether the efficacy of UV-C irradiation against biodeterioration of leather was concluded to be effective. This method can be used to control fungal growth without compromising the leather quality. Note de contenu : - MATERIALS AND METHODS : Isolation and identification - Biodeterioration study on leather - UV exposure study on fungal infected leather - Analysis - RESULTS AND DISCUSSION : Weight loss measurement - Physical strength analysis - FT-IR analysis - SEM and SEM–EDX analysis - Conceptual model for UV-C irradiation - Table 1 : Tensile strength and percentage of elongation at break of vegetable tanned leather sample - Table 2 : Tensile strength and percentage of elongation at break of chrome tanned leather sample - Table 3 : Elemental analysis of vegetable tanned leather sample after 30 days - Table 4 : Elemental analysis of chrome tanned leather sample after 30 days Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38222 [article]

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