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An investigation of the ethiopian tanning industry's competitiveness / Fitsum Etefa Ahmed in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXVIII, N° 2 (02/2023)
[article]
Titre : An investigation of the ethiopian tanning industry's competitiveness Type de document : texte imprimé Auteurs : Fitsum Etefa Ahmed, Auteur ; Melkamu Mengistenew Teshome, Auteur ; Awoke Fenta Wodag, Auteur ; Aragaw Bizualem Kassie, Auteur ; Tamrat Tesfaye, Auteur ; Kefyalew Alemayehu Wondmagegn, Auteur ; Lwubtujuibe Lwubtuguha, Auteur ; Hailekiros Debesay, Auteur ; Lijalem Melie Tesfaw, Auteur Année de publication : 2023 Article en page(s) : p. 59-66 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Compétitivité (économie politique)
Cuirs et peaux -- Industrie -- Ethiopie
Tanneries -- EthiopieIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Ethiopia’s leather development plan has prioritized the tanning industry in order to accelerate the sector’s growth. The aim of this study is to identify the factors that allow and prohibit Ethiopian tanning industries from coping with competitive challenges, as well as the competitive advantages and drawbacks that the tanning industry faces.The study followed a primary and secondary data collection methods, which included both qualitative and quantitative approaches. In the study, 13 functioning tanneries in the country involved in leather production from 2020 to 2021 were investigated. The study data were collected through distributing structured questionnaire and having interviews with tanning industry top management body (i.e. managers, directors, and heads). The study results are presented in forms of the mean and standard deviation. The study findings revealed that the tanning industry competitiveness is low due to different determinates factors. With the exception of the country’s natural resource endowment in hides and skins and low labor cost availability, all determinants of competitiveness (raw material, infrastructure, skilled labor, industry and institution linkage, capital and managerial capability, and government policy) are found to be insignificant. Similarly, the tanning industry’s ability to use its cost advantage in raw hides and skins and maintain its market share on the domestic and international market is limited by poor quality of locally supplied raw material, lack of strong supporting institutions and association’s, lack of infrastructure, capital and managerial capability, poor industry and institution linkage as well as factors such as scarcity of skilled labor and raw materials (chemicals and spare parts). In order to enhance the competitiveness of the tanning industry in the country, the industry, government and stakeholders need to work in collaboration in creating strong supporting industries, fulfilling infrastructure, providing investment capital, and supplying experienced managers and skilled workers. Note de contenu : - METHODOLOGY : Data collection
- RESULTS AND DISCUSSION : Method of data processing and analysis - General information of respondent - General information of the tanning industry - Tanning industry ownership status - Analysis of determinant factors of competitiveness - Raw material determinant factors of competitivness - Infrastructure determinant factors of competitiveness - Industry and institution linkage determinant factors of competitiveness - Skilled labor determinant factors of competitiveness - Government policy dterminant factors of competitiveness : Government policy as a factor - Fapital and managerial capability determinant factors of competitiveness - Competitiveness measure factors
- Table 1 : Respondent position in the tanning industries
- Table 2 : Name and place of the tanning industries available
- Table 3 : Ownership of tanning industry
- Table 4 : The degree of mean scores based on the criteria for clas interval scale rating
- Table 5 : Raw material determinant factors of competitiveness
- Table 6 : Infrastructure determinant factors of competitiveness
- Table 7 : Industry and institution linkage determinant factors of competitiveness
- Table 8 : Skilled labor determinant factors of competitiveness
- Table 9 : Government policy determinant factors of competitiveness
- Table 10 : Capital and managerial capability determinant factors of competitivnesss
- Table 11 : Competitiveness measure factorsEn ligne : https://drive.google.com/file/d/1rrySHeKtEQaX7818mtvQm1zToRLg2jtl/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38812
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXVIII, N° 2 (02/2023) . - p. 59-66[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 23871 - Périodique Bibliothèque principale Documentaires Disponible Exploring structural features of bovine, ovine, fish, poultry, reptile, amphibian, and porcine skins through scanning electron microscopy / R. Karthikeyan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIX, N° 5 (05/2024)
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Titre : Exploring structural features of bovine, ovine, fish, poultry, reptile, amphibian, and porcine skins through scanning electron microscopy : insights for material science and sustainable design Type de document : texte imprimé Auteurs : R. Karthikeyan, Auteur ; Zerihun Teshome, Auteur ; Tamrat Tesfaye, Auteur Année de publication : 2024 Article en page(s) : p. 207-214 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux -- Analyse
Cuirs et peaux de bovins
Cuirs et peaux de grenouilles
Cuirs et peaux de moutons
Cuirs et peaux de Poissons
Cuirs et peaux de porcs
Cuirs et peaux de volailles
Microscopie électronique à balayage
TopographieIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : In leather research, the Scanning Electron Microscope (SEM) proves to be an invaluable tool, offering detailed and high-resolution images of both the surface and fiber structure. This information plays a critical role in optimizing manufacturing processes within the leather industry, enhancing the quality of leather products, and contributing to the development of new materials. In the current study, our focus is on unraveling the microscopic details of skins sourced from various biological origins. We aim to provide insights into the distinctive morphological features, fiber arrangements, and surface topographies of bovine, ovine, fish, poultry, reptile, amphibian, and porcine skins, which were converted into crust leathers. We captured microphotographs of the surfaces and crosssections of the leathers through scanning electron microscopy analysis. This paper presents a comprehensive comparison and discussion of the findings, seeking to identify key differences and similarities. Such a comparative analysis contributes to our understanding of material science, fashion, and sustainable design, offering potential implications for these diverse fields. Note de contenu : - EXPERIMENTAL : Materials - Material preparation for structural investigation - SEM study of crust leathers
- RESULTS AND DISCUSSION : Structural characterization of bovine and ovine leathers - Structural characterization of fish leathers - Structural characterization of poultry leathers - Structural characterization of reptile leathers - Structural characterization of pig and frog leathersDOI : https://doi.org/10.34314/81027s27 En ligne : https://drive.google.com/file/d/1Oim8_1wTCHXPbPbVq0vW4wSjFodtarqe/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40974
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Code-barres Cote Support Localisation Section Disponibilité 24675 - Périodique Bibliothèque principale Documentaires Disponible Optimizing soft leather production from back cut skins : Sustainable practices at ethiopian Nile crocodile farms / Gemechu Chala in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIX, N° 8 (08/2024)
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Titre : Optimizing soft leather production from back cut skins : Sustainable practices at ethiopian Nile crocodile farms Type de document : texte imprimé Auteurs : Gemechu Chala, Auteur ; R. Karthikeyan, Auteur ; Tamrat Tesfaye, Auteur Année de publication : 2024 Article en page(s) : p. 331-338 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Crocodile du Nil
Cuirs et peaux -- Analyse
Cuirs et peaux -- Propriétés organoleptiques
Cuirs et peaux -- Propriétés physiques
Essais (technologie)
Souplesse (mécanique)
Tannage au chromeIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : This research addresses the significant challenges in converting back cut skins of Nile crocodiles (Crocodylus niloticus) into soft leather. The process is complicated by the skins’ inherent hardness and distinct texture. Sourced from the Arba Minch Crocodile Farm, these skins are aesthetically pleasing due to their unique scale patterns. However, they are often overlooked by leather manufacturers because of their rigidity and the complexities involved in processing. Our study proposes a critical modification in the pickling and chrome tanning process, specifically designed to improve fiber opening and separation. This method effectively transforms the durable back cut skins into flexible, soft leather, enhancing their applicability in various leather goods. Furthermore, the research encompasses an extensive evaluation of the raw materials, focusing on their fat and nitrogen composition. Advanced techniques, such as scanning electron microscopy analysis, along with visual examinations and physical tests, affirm the modified tanning process’s efficacy in producing soft leather from crocodile back cut skins. These findings underscore the potential of this refined approach not only to overcome processing challenges but also to expand the use of back cut skins in the leather industry. This research not only offers new opportunities for product diversification but also promotes sustainable practices at Ethiopian Nile Crocodile Farms, contributing to innovative and environmentally responsible leather production methods. Note de contenu : - EXPERIMENTAL : Materials - Determination of moisture content - Determination of fat content - Determination of protein content - Process details for conversion of back cut skins into soft crocodile leathers - Scanning electron microscopy of back cut crocodile leathers - Physical testing of leathers - Organoleptic properties
- RESULTS AND DISCUSSION : Crocodile back cut skins : Moisture, nitrogen and fat content - Effect of tanning on the structural characteristics of back cut leather - Physical and organoleptic properties of tanned crocodile back cut leathers
- Table 1 : Physical properties of back cut crocodile leathersDOI : https://doi.org/10.34314/bg0z6y08 En ligne : https://drive.google.com/file/d/1gFZkONhvqRRO_a1PzzyZ0he-Jjsv_7ym/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41286
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXIX, N° 8 (08/2024) . - p. 331-338[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 24767 - Périodique Bibliothèque principale Documentaires Disponible Xylanase-assisted fibre opening - A sustainable approach to stingray leather production / R. Karthikeyan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 108, N° 3 (05-06/2024)
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Titre : Xylanase-assisted fibre opening - A sustainable approach to stingray leather production Type de document : texte imprimé Auteurs : R. Karthikeyan, Auteur ; Zerihun Teshome, Auteur ; Genet Teka, Auteur ; Biniyam Solomon, Auteur ; Tamrat Tesfaye, Auteur Année de publication : 2024 Article en page(s) : p. 147-155 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Chaux Sulfurée
Dépigmentation de la peau
EnzymesUne enzyme est une protéine dotée de propriétés catalytiques. Pratiquement toutes les biomolécules capables de catalyser des réactions chimiques dans les cellules sont des enzymes ; certaines biomolécules catalytiques sont cependant constituées d'ARN et sont donc distinctes des enzymes : ce sont les ribozymes.
Une enzyme agit en abaissant l'énergie d'activation d'une réaction chimique, ce qui accroît la vitesse de réaction. L'enzyme n'est pas modifiée au cours de la réaction. Les molécules initiales sont les substrats de l'enzyme, et les molécules formées à partir de ces substrats sont les produits de la réaction. Presque tous les processus métaboliques de la cellule ont besoin d'enzymes pour se dérouler à une vitesse suffisante pour maintenir la vie. Les enzymes catalysent plus de 5 000 réactions chimiques différentes2. L'ensemble des enzymes d'une cellule détermine les voies métaboliques qui peuvent avoir lieu dans cette cellule. L'étude des enzymes est appelée enzymologie.
Les enzymes permettent à des réactions de se produire des millions de fois plus vite qu'en leur absence. Un exemple extrême est l'orotidine-5'-phosphate décarboxylase, qui catalyse en quelques millisecondes une réaction qui prendrait, en son absence, plusieurs millions d'années3,4. Comme tous les catalyseurs, les enzymes ne sont pas modifiées au cours des réactions qu'elles catalysent, et ne modifient pas l'équilibre chimique entre substrats et produits. Les enzymes diffèrent en revanche de la plupart des autres types de catalyseurs par leur très grande spécificité. Cette spécificité découle de leur structure tridimensionnelle. De plus, l'activité d'une enzyme est modulée par diverses autres molécules : un inhibiteur enzymatique est une molécule qui ralentit l'activité d'une enzyme, tandis qu'un activateur de cette enzyme l'accélère ; de nombreux médicaments et poisons sont des inhibiteurs enzymatiques. Par ailleurs, l'activité d'une enzyme décroît rapidement en dehors de sa température et de son pH optimums.
GaluchatLe galuchat (1755 galucha, de Jean-Claude Galluchat, nom de l'inventeur, mort en 1774) est un cuir de poisson cartilagineux (de raie ou de requin) utilisé depuis longtemps en ébénisterie, gainerie, et plus récemment en maroquinerie.
À mi-chemin entre le cuir et le minéral, le galuchat est recouvert de perles de silice donc difficile à tanner. Il présente différents aspects : granuleux et brillant, ou bien poncé : dans ce cas, il est lisse et laisse apparaître une surface cloisonnée de petites cellules.
Ouverture des fibres (cuirs et peaux)
Peau -- Histologie
Pollution -- Mesure
Stabilité thermique
XylanaseIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : The unique and distinctive texture of stingray skin is largely attributed to dermal denticles. These structures not only enhance the skin's uniqueness but also contribute to its remarkable hardness and toughness, qualities that persist even after traditional lime-sulfide fibre-opening treatments. However, conventional beamhouse operations, utilizing sulphide for dehairing and liming for fibre disaggregation, face global environmental and health criticism due to their significant pollution impact. Sulphide, a toxic chemical, increases the chemical oxygen demand load in effluents from hair decomposition, while lime usage, constituting approximately 10% of the raw skins' weight, results in substantial sludge production and disposal challenges. In response, this study explores the use of the enzyme xylanase for the depigmentation and disaggregation of the layered fibre structure in stingray skin. Following soaking, a 3% xylanase enzyme solution was applied, followed by pickling and chrome tanning. We assessed the structural and physical properties of the treated leathers and evaluated the pollution load parameters of the xylanase-assisted fibre-opening process. A comparative analysis with the traditional lime-sulphide process was conducted to evaluate the efficacy and environmental impact of the xylanase method. The results of this comparison are detailed herein, highlighting the potential of xylanase as a sustainable alternative in stingray leather processing. Note de contenu : - EXPERIMENTAL SECTION : Materials - Xylanase assisted depigmentation and fibre opening method - Conventional lime sulphide process - Determination of thermal stability by Differential Scanning Calorimetry (DSC) - Histological studies - Scanning Electron Microscopy (SEM) analysis - Histological studies with Alcian blue - Pollution load measurement - Post tanning - Physical testing
- RESULTS AND DISCUSSION : Effect of xylanase on fibre opening : Histological evaluation with Van Gieson stain - Effect of xylanase on fibre opening : SEM studies - Effect of xylanase on glycosaminoglycans - Xylanase treated leather : Thermal stability insights from DSC analysis - Pollution analysis : Xylanase vs. Lime sulphide fibre opening - Physical characteristics of xylanase treated stingray leather
- Table 1 : Post tanning procedures for stingray leathers
- Table 2 : Comparative pollution load analysis of xylanase-based and lime sulphide fibre opening methods
- Table 3 : Physical properties of stingray crust leathersPermalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41141
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