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An effective way to prepare high performance biomass-based fatliquoring agent - Bromination modification of rapeseed oil and its fatliquoring and flame-retardant properties / Tao Luo in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXVIII, N° 8 (08/2023)
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Titre : An effective way to prepare high performance biomass-based fatliquoring agent - Bromination modification of rapeseed oil and its fatliquoring and flame-retardant properties Type de document : texte imprimé Auteurs : Tao Luo, Auteur ; Xu Zhang, Auteur ; Biyu Peng, Auteur ; Chunxiao Zhang, Auteur ; Sadaqat Ali Chattha, Auteur Année de publication : 2023 Article en page(s) : p. 346-353 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Absorption
Analyse sensorielle
Biomasse
BromationSubstitution dans une molécule d'un atome d'hydrogène par un atome de brome.
Combustion
Croûte (cuir)On entend par "cuir en croûte" des cuirs ayant subi les opérations jusqu'au tannage, à l'exclusion de toute opération de corroyage ou de finissage, mais qui, par opposition aux wet-blue ont été séchés.
Cuirs et peaux -- Analyse
Douceur (toucher)
Essais accélérés (technologie)
Essais de résilience
Fourier, Spectroscopie infrarouge à transformée de
Huile de colza
IgnifugeantsComposé chimique utilisé pour réduire l'inflammabilité. Il peut être incorporé au produit durant sa fabrication ou appliqué ultérieurement à sa surface.
Produits de nourriture du cuirIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : With the implementation of Carbon Neutralization strategy, it is urgently needed to develop low-carbon leather chemicals through replacing petrochemicals with biomass-based raw materials in leather industry. To solve the problems existing in the leather fatliquored by the biomass-based fatliquoring agents made from vegetable oils with high unsaturation, such as poor storability, unpleasant odor, yellowing and possible formation of hexavalent chromium, the strategy was put forward, improving the oil saturation through the double bonds addition reaction with halogen to solve the abovementioned problems resulting from the poor oxidation resistance of oil, and increase the binding ability of the oil with leather fibers and endow the leather with flame-retardant simultaneously. In this paper, the methods of modified rapeseed oil by bromine addition and its fatliquoring and flame-retardant properties were studied. The results showed that the bromine addition reaction of rapeseed oil was easy to proceed and the iodine value of the modified oil decreased almost linearly with the added amount of bromine. The binding and antioxidant properties of the oil and the physical properties of the fatliquored leather were significantly improved with the increase degree of bromination modification. Furthermore, above mentioned unpleasant odor, yellowing and hexavalent chromium formation problems were effectively solved when the iodine value of modified fatliquors was reduced to 31 g I2/100 g. Additionally, brominemodified rapeseed oil could endow leather with good flame-retardant properties and the fatliquored leather was changed from combustible to flame-retardant material with the increasing amount of bromine in the oil. The limit oxygen index (LOI) increased from 24% to 31%, the flame combustion time decreased from 127.0 s to 4.3 s, and the flameless combustion time decreased from 28.5 s to 0.0 s. This study provided an effective way to develop biomass-based and low-carbon fatliquors based on natural unsaturated oils. Note de contenu : - MATERIALS AND METHODS : Materials - Bromination modification of rapessed oil - Preparation of leather fatliquoring agent - Application of fatliquors in the fatliquoring process - Determination of the iodine value of oils - Fourier Transform Infrared Spectroscopy (FT-IR) of oils - Absorption rate of fatliquors - Distribution of Br element and collagen fibers - Binding ability of modified oils with leather fibers - Limiting oxygen index (LOI) test of crust leather - Vertical combustion test of crust leather - Ageing test of crust leather - Odor level evaluation of crust leather - Yellowing resistance property of crust leather - Softness and physical properties of crust leather
- RESULTS AND DISCUSSION : Preparation and characterization of bromine-modified rapessed oil - Absorption rate of oil and its distribution in leather - Effect of rapessed oil modification degree on the properties of fatliquored leather
- Table 1 : Absorption rate of fatliquors
- Table 2 : Oil extraction test results
- Table 3 : Leather vertical combustion test results
- Table 4 : Leather softness test resultsDOI : https://doi.org/10.34314/jalca.v118i8.8092 En ligne : https://drive.google.com/file/d/12reqFQXSFwDRWiNVXr_pFHQVWb2biTpR/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39674
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXVIII, N° 8 (08/2023) . - p. 346-353[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 24134 - Périodique Bibliothèque principale Documentaires Disponible An environmentally friendly leather-making process based on silica chemistry / Yuansen Liu in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CV, N° 3 (03/2010)
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Titre : An environmentally friendly leather-making process based on silica chemistry Type de document : texte imprimé Auteurs : Yuansen Liu, Auteur ; Chen Yi, Auteur ; Jian Yao, Auteur ; Haojun Fan, Auteur ; Bi Shi, Auteur ; Biyu Peng, Auteur Année de publication : 2010 Article en page(s) : p. 84-93 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : An environmentally friendly leather process involving a lime-free liming process and a nano-SiO2 tanning process based on silica chemicals was investigated. The investigation included evaluation of the environment characteristics of this process, gelatin recovery from shavings together with the hydrothermal stability and mechanical properties of resultant leathers. The results indicated that the lime-free liming process based on sodium silicate and enzyme had an equivalent effect on fiber opening compared with conventional liming process. The physical strength and shrinkage temperature of the resultant leather tanned with nano-SiO2 were all higher than the stipulated chinese standards of chrome-free leather and were close to the chrome tanned leather control. More importantly, the lime sludge and chromium were at zero discharge because lime and chrome were not used in this experimental in this experimental proces. The total water consumption, raw shin basis, was decreased from 16.15L./Kg to 14.20L/Kg. At the same time, the values of biochemical oxygen demand (BOD5), the chemical oxygen demand (COD), the total nitrogen content (TNC) and total solids (S) in wastewater were all lower than the conventional process, showing reductions of 30 %, 45 %, 55 % and 72 %, respectively. BOD5/COD analysis revealed that the waste water from experimental treatment was more biodegradable than that of control treatment. Another interesting result was that the nano-SiO2 shavings produced in this process could be easily reused. High quality gelatin without chromium was obtained and large amount of water and chemical materials was saved in recovery process, so the secondary pollution caused by the traditional recovery of chrome shaving could be avoided. En ligne : https://drive.google.com/file/d/12yIYt3clTocc0TfDF3GZQ0P6CG6X2IxL/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8733
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Code-barres Cote Support Localisation Section Disponibilité 012029 - Périodique Bibliothèque principale Documentaires Disponible Application of acidic protease in the pickling to simplify the pelt bating process / Xu Zhang in JOURNAL OF LEATHER SCIENCE AND ENGINEERING, Vol. 3 (Année 2021)
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Titre : Application of acidic protease in the pickling to simplify the pelt bating process Type de document : texte imprimé Auteurs : Xu Zhang, Auteur ; Mengchu Gao, Auteur ; Sadaqat Ali Chattha, Auteur ; Yiwen Zhu, Auteur ; Biyu Peng, Auteur ; Yongbin Ye, Auteur Année de publication : 2021 Article en page(s) : 14 p. Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Confitage Le confitage est une action biochimique effectuée au moyen de produits enzymatiques, qui a pour but de dégrader les fibres élastiques, contribuant ainsi à augmenter la souplesse du cuir. En outre, les enzymes complètent la dégradation des résidus épidermiques, donnant ainsi une fleur plus propre et plus lisse.
Croûte (cuir)On entend par "cuir en croûte" des cuirs ayant subi les opérations jusqu'au tannage, à l'exclusion de toute opération de corroyage ou de finissage, mais qui, par opposition aux wet-blue ont été séchés.
Cuirs et peaux
Peptidases
PicklageLe picklage consiste à faire absorber à la peau en tripe une quantité importante d'acide, en présence de sel neutre (NaCl) pour réprimer le gonflement que provoquerait l'acidité du milieu.
TrypsineLa trypsine (EC 3.4.21.4) est une enzyme digestive du suc pancréatique qui a pour rôle de digérer les protéines.
Elle est synthétisée par le pancréas sous forme de trypsinogène (proenzyme inactive), puis stockée dans les vésicules enzymatiques des cellules acineuses d'où elle est excrétée au moment de la digestion. L'activation du trypsinogène en trypsine est le résultat de l'hydrolyse d'un propeptide sous l'action de l'entérokinase ou par un effet d'autoactivation de la trypsine par elle-même. La cholecystokinine-pancréozymine active la sécrétion des enzymes (donc de la trypsine) dans le suc pancréatique.
La trypsine est une endoprotéase qui hydrolyse les liaisons peptidiques dans lesquelles un acide aminé basique (Lys-|-Xaa ou Arg-|-Xaa) engage sa fonction acide (sauf dans le cas où l'acide aminé suivant (schématisé ici par "Xaa") est une Proline). Elle coupe en C-terminal de ces acides aminés. En d'autres mots, elle transforme les chaînes polypeptides en chaînes protéiques plus courtes pour permettre la digestion. Efficace à pH 7,5 - 8,5, elle est inactivée et digérée en quelques heures à pH neutre (=7) dans l'intestin.
La trypsine participe à l'activation d'autres enzymes comme l'alpha-chymotrypsine par coupure hydrolytique de la chaîne polypeptidique du chymotrypsinogène.
Cette enzyme sert également lors de la 2e semaine du développement embryonnaire humain. Elle est sécrétée par le trophoblaste afin de digérer la zone pellucide entourant le blastocyste. Ce phénomène s'appelle l'éclosion.Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Traditionally, universally used pelt bating technologies rely on the application of trypsin, neutral and alkaline microbial proteases but suffer from complicated operation, limited bating efficiency and unsatisfactory leather performance. Therefore, devising a new pelt bating approach to achieve high bating efficiency and excellent leather performance has always been wished for by the leather industry. To pursue this goal, years of persistent research work enabled us to develop a novel approach for pelt bating by means of acidic proteases in pickling process. Initially, basic enzymatic characteristics and bating effectiveness of several typical acidic proteases in pelt pickling medium were investigated; then, the bating effectiveness through the quantitative characterization of protease activity of the optimal acidic protease was compared with that of the conventional bating enzyme. The results indicated that all of the selected acidic proteases had good salt-tolerance and exhibited optimum activity at pH 3.0–4.0. The novel pickling-bating method based on microbial origin acidic protease L80A led to an outstanding performance on pelt bating at the dosage of 150 U/mL of collagenolytic activity. The bating effectiveness of acidic protease L80A was comparable to and even better than that of trypsin BEM due to its moderate proteolytic ability. Moreover, the deep and even penetration of acidic protease in the pelt permitted it to produce soft, organoleptically stable and overall better quality crust leather than that of the conventional trypsin bating method. Additionally, pelt bating was performed along with the pickling process without extra inactivation and washing operation, making the bating operation more efficient, economical, and environment friendly. Results had made us to conclude that this cutting-edge acidic proteases based pickling-bating method could be the first step/ way forward to replace the decades-old traditional pelt bating technology. Note de contenu : - MATERIALS AND METHODS : Materials - Assay of proteolytic activity on casein substrate - Assay of proteolytic activity on collagen fiber substrate - Effect of salt concentration on the collagenolytic activity of acidic proteases - Bating pickling pelt with typical proteases - Comparison of the bating effectiveness of acidic protease L80A and trypsin BEM - Determination of soluble protein (SP) concentration in bating liquor - Determination of hydroxyproline concentration in bating liquor - Determination of chromium content in spent tanning liquors and wet blue - Histological analysis of collagen and elastin fiber - Scanning electron microscopy (SEM) analysis - Test of softness and physical properties of crust leather
- RESULTS : Proteolytic characteristics of typical acidic proteases - Comparison bating effectiveness of different acidic proteases in pickling process - Relationship between collagenolytic activity and bating effect of pickling pelts - Comparison of bating effectiveness of the novel pickling-bating and conventional trypsin bating method
- Table 1 The selected proteases
- Table 2 Enzymatic characteristics of acidic proteases (25 ℃, pH 3.5)
- Table 3 Amounts of proteases, soluble protein, hydroxyproline in the bating liquor and the softness of crust leather treated by the same dosage of caseinolytic activity (25℃, pH 3.5)
- Table 4 Amounts of proteases, soluble protein, hydroxyproline in the bating liquor and the softness of crust leather treated by the same dosage of collagenolytic activity (25℃, pH 3.5)
- Table 5 Relation of the softness and physical properties of the crust leathers to the collagenolytic activity of protease L80A (25℃, pH 3.5)
- Table 6 Amounts of protease and testing results of the effluents and crust leathersDOI : https://doi.org/10.1186/s42825-021-00068-x En ligne : https://link.springer.com/content/pdf/10.1186/s42825-021-00068-x.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37552
in JOURNAL OF LEATHER SCIENCE AND ENGINEERING > Vol. 3 (Année 2021) . - 14 p.[article]Characteristics of leather tanned with Nano-SIO2 / Haojun Fan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. C, N° 1 (01/2005)
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Titre : Characteristics of leather tanned with Nano-SIO2 Type de document : texte imprimé Auteurs : Haojun Fan, Auteur ; Biyu Peng, Auteur ; Qiang He, Auteur ; Bi Shi, Auteur ; Ling Li, Auteur Année de publication : 2005 Article en page(s) : p. 22-28 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : A nano-precusor which can, in-situ, produce nano-SiO2 under particular triggering condition was introduced into leather to improve the hydrothermal stability. In order to elucidate the reaction of nano-SiO2 with proteinand how it influences the properties of the protein, collagen was used as a model in a detailed investigation. The results from FTIR (Infrared) indicated that two new chemical bonds arose during the formation of the organic-inorganic nano-hybrid. One appears to be the reaction between nano-SiO2 formed in-situ by the hydrolysis of tetraethoxy silane and the -C=N-groups of arginine, histidine, and tryptophane in the backbone of collagen. In a second bond, occurring at the same time as the condensation of silanol proceeds, the pendent hydroxyl groups of collagen may partly react with Si-OH and form a strong interaction between the organic and inorganic phases. These two chemical bonds seem to contribute to the leather's high hydrothermal stability. The size distribution of nano-SiO2 as determined by Atomic Force Microscopy is approximately 50-80 nm and there appeared to be no agglomeration. Organic-inorganic nano-hybrid can improve the hydrolysis stability of collagen efficiently in the presence of enzyme, acid, and alkali. When the bated pelt is treated with 0.3 wt % nano-SiO2 (based on bated pelt weight), the shrinkage temperature reached above 95°C. Although the mechanical properties of nano-SiO2 tanned leather are inferior to chromium tanned leather, other properties of nano-SiO2 tanned leather, such as yield, grain, fullness and softness together with washability are all superior to chromium tanned leather. En ligne : https://drive.google.com/file/d/1ohLq2CUJ-Oo_mR-8noT-ldL7pN59s7c6/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4087
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Code-barres Cote Support Localisation Section Disponibilité 000685 - Périodique Bibliothèque principale Documentaires Disponible Covalent immobilization of organophosphorus hydrolase onto insoluble bovine collagen fibers / Yanhong Li in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CIX, N° 6 (06/2014)
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Titre : Covalent immobilization of organophosphorus hydrolase onto insoluble bovine collagen fibers Type de document : texte imprimé Auteurs : Yanhong Li, Auteur ; Xinju Jia, Auteur ; Biyu Peng, Auteur Année de publication : 2014 Article en page(s) : p. 197-206 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Caractérisation
Cinétique chimique
Glutaraldéhyde
Hydrolase
pH
Poudre de peaux
TempératureIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : An organophosphorous hydrolase (OPH) was prepared and partially purified from Flavobacterium sp. The crude enzyme, with an activity of 1030U/g, was immobilized onto insoluble bovine collagen fibers (hide powder), instead of collagen membrane, through glutaraldehyde coupling. Optimal conditions of enzyme immobilization and properties of the immobilized enzyme preparation were investigated. Compared to glutaraldehyde tanned and chrome tanned hide powders, non-tanned hide powder showed higher immobilized enzyme activity. The optimal enzyme immobilization conditions are as follows: 10mg of enzyme was immobilized onto 500mg of hide powder in a 50mM phosphate buffer of pH 7.5 at 20°C, and 20% glutaraldehyde offer (based on the hide powder weight) was used to couple the enzyme and collagen fibers. The enzyme activity yield was about 35% and the hide powder immobilized OPH has an enzyme activity of about 7U/g. The immobilized enzyme showed the same temperature and pH profiles as the free enzyme, and it performed at much higher pH and with better thermal stability. The Km value of the immobilized enzyme was a somewhat higher (0.388mM) than that of the free enzyme (0.215mM). The reusability test showed that about 85% activity was retained after 10 use cycles. After storing for eight months at 20°C, the residual activity of the immobilized enzyme preparation was 98%. Note de contenu : - MATERIALS AND METHODS : Materials - Methods (Preparation and partial purification of organophosphorus hydrolase (OPH) from flavobacterium sp. - Preparation of tanned hide powder - OPH activity assay - OPH activity stability against glutaraldehyde - Immobilization of OPH on hide powders - Activity assay and characterization of immobilized OPH)
- RESULTS AND DISCUSSION : The influence of glutaraldehyde on OPH activity - Factors affecting immobilization of OPH on hide powder (OPH immobilized on different hide powders - Effect of pH - Effect of glutaraldehyde dosage - Effect and temperature - Effect of added enzyme amount) - Characterization of immobilized OPH (pH and temperature-activity profiles - pH and thermal stability of immobilized enzyme - Kinetics parameters - Operational and storage stability)En ligne : https://drive.google.com/file/d/1-aAAxLzbsyLkcO9tzzpc_gUMX5hFAqhP/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21518
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Code-barres Cote Support Localisation Section Disponibilité 16325 - Périodique Bibliothèque principale Documentaires Disponible 16406 - Périodique Bibliothèque principale Documentaires Disponible Effect of electrostatic interaction between collagen and enzymes on permeation of protease into the pelt during leather bating process / Yiwen Zhu in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXVIII, N° 10 (10/2023)
PermalinkEffects of calcium content on the enzymatic bating of delimed hides / Chunxiao Zhang in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXVII, N° 12 (12/2022)
PermalinkEnzymatic balting technology for wet blue : I. Characterization of protease activities towards chrome-tanned elastin and collagen fibers / Xu Zhang in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIII, N° 7 (07/2018)
PermalinkEnzymatic bating technology for wet blue : II. The basic properties and application effectiveness of typical acidic proteases / Xu Zhang in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXV, N° 12 (12/2020)
PermalinkExploration of the diffusion, binding and crosslinking of chromium complex within hides during chrome tanning / Chunxiao Zhang in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIV, N° 5 (05/2019)
PermalinkHigh-efficiency bio-degreasing technology for leather making - Characterization of catalytic hydrolysis properties of lipases towards fats based on greasy skin powder substrate / Yongkang Luo in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIV, N° 11 (11/2019)
PermalinkIdentification of gaps in knowledge and practices affecting the quality of skins/hides on the eve of Eid-ul-Adha in Pakistan / Sadaqat Ali Chattha in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXVIII, N° 11 (11/2023)
PermalinkInfluence of hydrophobic side chain structure on the performance of amphiphilic acrylate copolymers in leather making / Jinxia Du in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 100, N° 2 (03-04/2016)
PermalinkKey mechanism of enzymatic dehairing technology for leather-making : permeation behaviors of protease into animal hide and the mechanism of charge regulation / Mengchu Gao in COLLAGEN AND LEATHER, Vol. 5 (2023)
PermalinkMinimization of chromium discharge in leather processing by using methanesulfonic acid : A cleaner pickling-masking-chrome tanning system / Chunxiao Zhang in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXI, N° 12 (12/2016)
PermalinkNano-SiO2-oxazolidine combination tannage-potential for chrome-free leather / Lu Yan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 92, N° 6 (11-12/2008)
PermalinkA novel approach for quantitative characterization of hydrolytic action of glycosidases to glycoconjugates in leather manufacturing / Fengxiang Luo in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXV, N° 7 (07/2020)
PermalinkNovel titanium (IV) tanning for leathers with superior hydrothermal stability / Biyu Peng in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CII, N° 9 (09/2007)
PermalinkNovel titanium (IV) tanning for leathers with superior hydrothermal stability / Biyu Peng in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CII, N° 10 (10/2007)
PermalinkPerformance evaluation of pelts and leather from domestic hair sheep crossbreeds / Dennis C. Shelly in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CIV, N° 6 (06/2009)
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