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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1511

Sûreté de fonctionnement des convertisseurs - Nouvelles structures de redondances pour onduleurs sécurisés à tolérance de pannes / Dependability of the converters : New structures for inverters redundancy secure fault-tolerant

Dou, Zhifeng 04 November 2011 (has links)
Au sein d'un convertisseur la défaillance d'un composant de puissance est un événement critique tant par le risque d'explosion du boitier et sa propagation au sein du système (forte énergie stockée dans l'alimentation) que par l'interruption de service qui en découle (systèmes embarqués, systèmes de production en flux tendu). Ce mémoire de thèse propose un ensemble de solutions nouvelles portant sur la problématique de l'isolement ultime de défauts "derniers secours" d'une part, et sur la connexion "automatique" et à faible "coût" d'un circuit en secours. L'objectif de cette approche globale est de concilier "sécurité électrique absolue" et "continuité de service" pour les systèmes de conversion sensibles devant être intégrés au coeur des applications critiques. Le premier chapitre et son annexe permettent de rappeler les causes et les conséquences des défauts internes au sein d'une structure de base d'onduleur à deux niveaux de tension, laquelle fait l'objet de nombreuses simulations de modes dégradés en configuration variateur de vitesse sur machine synchrone. De cette analyse il ressort qu'une structure d'isolement symétrique à deux voies couplées, placées sur les pôles du bus DC, à déclenchement spontané (fusible) et/ou commande (rupteur), est à même de sécuriser toutes les mailles du circuit, de façon modulaire et non intrusive. / In all these traditional industries, or in more sensitive sectors and high technology, it appears that the safe operation of power systems becomes a critical and strategic area essential. In the area of application that focuses, design dependability and now rests primarily on an approach to reliability of components used, the use of close protection, monitoring alarms and management stop / reset / recovery. In our view, this approach is incomplete quickly when electrical safety and absolute continuity of a permanent mission should be carried out simultaneously in the presence of an internal failure of sensitive functions for low and medium power (eg, orders and bodies actuation of vehicles) or highly critical (nuclear). In this area, topologies and failure modes are at the heart of the problem. In this paper, we will focus primarily on the inverters and choppers structures at two levels of voltage (single-cell arm, <1kV), with simple configuration and multiphase parallel, although the concepts are presented, as examples, partially extrapolated to the structures of three voltage levels (arms multicellular) and rectifier (low-frequency phase control and high-frequency switching PWM). We will highlight the need to limit the intensity of these failures and to electrically isolate the defective cell and symmetrically of this inverter by multipole devices, passive or spontaneous breaking mixed cut ordered in the form of fuses integrated and distributed of multi-channel passive isolators, to imagine and develop. We will show that this process of isolation of the last backup is needed to connect, form series or parallel to the defective cell, a cell rescue in passive redundancy. The cell structure backup connection pooled by spontaneous (automatic) is especially promising as detailed in our eyes because of its simplicity and its integrability. Next, we present the isolation technologies fuse (not included, miniatures, CMS and multilayer chip fuse), their characteristics, their current limitations and operating in a switching cell test. A methodology and design of symmetrical two-way fuse (dual-fuse) on FR4 PCB - Copper will be presented in Comsol ™ and evaluated initially in static thermal IR. A passive two-way switch, relatively original material for integrating energy embedded in FR4 substrate, will be presented and fully dimensioned plans on electrical, thermal and mechanical also using finite element simulations in Comsol ™. Another aspect of exploratory analysis, mainly experimental, or to characterize the failure modes of bullets and casings ultimate power compared between the technologies of encapsulation by epoxy resin (standard discrete case) and a silicone gel (module) is provided under conditions of stress controlled and reproducible. This step is necessary to characterize the resistive mode of a chip based on faulty stresses and stability over time of the residual strength according to the nature of the encapsulant, ie the very sustainability of this failure mode. A mixed-encapsulant resin - gel will be presented and characterized, providing an excellent compromise for medium power applications. Positive results and little known today, will allow us to exploit in the next chapter, this property of stable ohmic mode of the chip failed in a structure to aid automated connection series interesting. In the end, we will detail the demonstrator prototype and introduced to the context with which we will validate the isolation structures and prototypes fuses the property of stable ohmic mode highlighted in the aspect of technological analysis of selected devices. These results allow us to refine the solutions adopted for specifications and guide future management strategy of defects whether internal or external to the topology. Supervisor digital device - sensor for the detection and reconfiguration of internal control orders will be assessed.
1512

Transferts dans les systèmes emballage/aliments : structuration à façon de matériaux multicouches pour l’emballage sous atmosphère modifiée des produits frais / Mass transfers in food/packaging systems : Structuring tailor-made multilayer materials for modified atmosphere packaging of respiring produce

Cagnon, Thibaut 13 November 2012 (has links)
Malgré l'ampleur que prend la technologie sous atmosphère modifiée pour le conditionnement des fruits et légumes frais, l'adéquation des matériaux d'emballage avec les besoins des produits est insuffisante. D'une part parce que la conception de ces emballages repose encore sur des approches empiriques de type essai-erreur, et d'autre part parce que la plupart des matériaux disponibles sur le marché présentent des propriétés de transfert aux gaz trop restreintes compte tenu de la gamme de propriétés nécessaire pour couvrir les besoins de ces produits. En vue d'apporter des solutions à ces deux verrous, les travaux de thèse ont porté sur :-la mise en place et la validation d'une approche basée sur l'ingénierie reverse visant à identifier les propriétés de transfert requises ou cibles pour un végétal donné ;-l'étude des procédés de structuration à différentes échelles pour moduler les propriétés de transferts de papiers enduits de protéines de blé, issus de ressources renouvelables.Une démarche d'ingénierie reverse organisée en 5 étapes dont l'identification des besoins des produits et la prédiction des propriétés de transferts requises a été proposée et validée à travers la conception d'un papier enduit actif pour l'emballage sous atmosphère modifiée adapté à la conservation de fraises. Les différents procédés de structuration étudiés ont permis de produire des matériaux couvrant des gammes de permsélectivité allant de 5 à 18 et de perméance à l'oxygène allant de 0,02x10-10 à 2x10-10 mol.Pa-1.m-2.s-2, ce qui répond parfaitement aux besoins d'une sélection représentative de produits frais respirant. Que ce soit des papiers enduits par des procédés conventionnels (couche épaisse) ou des procédés innovants (nano-structuration couche par couche en présence de feuillets d'argile, montmorillonites), il est possible de moduler les propriétés de transferts aux gaz des papiers enduits soit en jouant sur le raffinage des papiers supports, le nombre de paires de couche (gluten/montmorillonite), ou encore en soumettant les matériaux ainsi obtenus à un balayage gazeux de CO2. Cette nouvelle approche et l'efficacité des matériaux protéiques à couvrir les besoins des fruits et légumes ouvrent la voie à la conception de nouveaux emballages mieux adaptés aux produits respirant. / Despite the growing importance of the modified atmosphere packaging (MAP) technology for fresh fruits and vegetable preservation, the adequacy of the packaging materials with the produce needs remains a problem. On one hand because the packaging development approaches are still based on empirical trial and error methods, and on the other hand, because of the non-adequate gas transfer properties (too restricted to cover the large game of gas transfer properties required) of the vast majority of conventional synthetic plastics currently used for fresh food packaging. In order to overcome these hindrances, the thesis work was split on two parts:-the establishment and the validation of a new approach based on reverse engineering aiming to identify the optimal (targeted) properties for optimal preservation of a selected produce;-the study of the various structuration processes at different scales to modulated the gas transfer properties of bio-sourced wheat gluten coated papers.The new reverse engineering approach for MAP conception consisted in 5 steps including the definition of the produce needs and the prediction of the optimal gas transfer properties of the packaging, and was validated through the conception of an active optimal packaging for strawberry preservation. The different structuration processes studied allowed production of a gluten based materials able to cover ranges of permselectivity and oxygen permeations going from 5 to 18 and 0.02x10-10 à 2x10-10 mol.Pa-1.m-2.s-2, which perfectly matched the needs of a representative selection of fresh produce. Be it for conventional coating techniques (thick layer) or innovative processes (layer-by-layer nano-structuring of gluten/montmorillionites layers), it was possible to modulate the transfer properties of coated papers by changing the refining degree of the support paper, the number of layer pairs (gluten/montmorillionites) deposited, or even by submitting such materials to a CO2 treatment.This new approach and the efficiency of the protein-based materials for covering the fresh fruits and vegetable needs open the way for conception of new optimal packaging for respiring produces.
1513

Développement d'un matériau thermoplastique biodégradable et hydrosoluble à base d'une protéine du lait / Synthesis of a thermoplastic biodegradable and water soluble material based on a milk protein

Belyamani, Imane 08 November 2011 (has links)
La biomasse représente l’une des principales alternatives à l’utilisation du pétrole dans la plasturgie. Grâce à leurs propriétés fonctionnelles, les caséinates sont une matière première prometteuse pour la fabrication de films plastiques pour des applications dans l’emballage biodégradable et hydrosoluble. La transformation du caséinate de sodium par les techniques habituellement utilisées dans la plasturgie a été démontrée. Des extrudats de caséinate plastifié au glycérol ont été obtenus au moyen d’une extrudeuse bi-vis corotative. La caractérisation physico-chimique du matériau obtenu a confirmé la thermostabilité de cette protéine et a montré la dépendance du comportement du matériau vis-à-vis de l’humidité ambiante. Pour une variation du taux d’Humidité Relative, de 40 à 90% et une augmentation de la concentration du glycérol, plastifiant hygroscopique, le matériau passe d’un état vitreux (rigide) à un état caoutchouteux (mou). Des films fins ont été ensuite réalisés, à partir des extrudats thermoplastiques, par extrusion gonflage. La perméabilité à la vapeur d’eau des films de caséinate de sodium a été étudiée et a montré que ces matériaux sont de mauvaises barrières à l’humidité. La deuxième partie a été consacré à l’étude de mélanges caséinate de sodium/caséinate de calcium d’un côté et caséinate de sodium/PBAT de l’autre. Le mélange des deux caséinates a permis d’augmenter la tenue mécanique du mélange, à partir de 50% de caséinate de calcium, et de retarder le transfert hydrique à travers le film. Dans le même sens, l’ajout du PBAT, a augmenté jusqu’à deux fois plus, le module d’Young des mélanges mais a baissé la résistance au transfert d’humidité du film à cause de l’incompatibilité des deux polymères / Biomass is one of the main alternatives to the use of oil in plastics field. Due to their various functional properties, caseinates are considered as an interesting raw material for making biodegradable and water-soluble packaging. The transformation of sodium caseinate by the processes used for synthetic plastics industry has been demonstrated. A corotating twin-screw extruder was used to get glycerol plasticized caseinate pellets. The physicochemical properties of the obtained material have confirmed the thermal stability of this protein and demonstrated the influence of surrounding moisture on material behavior. With the Relative Humidity varying from 40 to 90% and increasing the glycerol content, an hydrous plasticizer, the mechanical properties of sodium caseinate based materials changed from those of glassy (rigid) to rubbery (soft) plastics. The pellets were then taken over to make film using a blown-film extruder. The water vapour permeability of blown film was studied and showed that sodium caseinate based films are a poor moisture barrier. The second part dealt with the sodium caseinate blend. Sodium caseinate/calcium caseinate and sodium caseinate/PBAT blends was performed. Adding calcium caseinate, started from 50%, improved the mechanical properties and delayed hydrous transfer through the film. Concerning the sodium caseinate/PBAT blends, adding PBAT increased until twice more the material’s Young modulus but decreased the moisture transfer resistance because of the incompatibility between the two polymers
1514

Le verre comme mode d’emballage en Provence à l’époque moderne et contemporaine : Industrie, productions, commerce (1720 – 1920) / Packaging glass in Provence in the modern and contemporary era : Industry, Products and Trade (1720 – 1920)

Serra, Laurence 08 December 2011 (has links)
Conditionner les produits alimentaires, pharmaceutiques et cosmétiques pour les conserver et les transporter a toujours été une nécessité pour des hommes à la fois consommateurs et commerçants. Cette étude, qui relève à la fois de l’histoire et de l’archéologie, souligne le rôle majeur joué par le verre, en Provence, au XVIIIe et au XIXe siècle, comme mode de conditionnement des marchandises de qualité. Depuis l’Antiquité jusqu’à nos jours, les produits de luxe, vins fins, huiles surfines et parfums sont protégés et mis en valeur par leur emballage en verre. Il est le matériau idéal car il possède toutes les qualités physiques et chimiques pour devenir fonctionnel et esthétique. Lorsque la Provence se lance, dans les premières décennies du XVIIIe siècle, à la conquête marchande des espaces maritimes, elle bénéficie d’une économie fondée sur la transformation d’agro-alimentaire local ou importé. L’industrie des emballages prend alors un essor considérable en Provence en lien avec cette économie. Les contenants en verre vont ainsi s’exporter à travers le monde, par bateau, grâce à l’action conjuguée de facteurs favorables : le rayonnement international du port de Marseille ainsi que les progrès techniques liés à l’adoption d’une nouvelle source d’énergie, le charbon. Influencée par l’exemple des autres régions, françaises et européennes, la verrerie provençale connaît une métamorphose notable qui conduit à l’abandon progressif des ateliers forestiers au profit d’une implantation portuaire. Sources écrites et iconographiques constituent une grande part de notre documentation complétée par les sources archéologiques. Elles sont liées principalement à la découverte et à l'étude récente d'épaves ainsi qu'à l'inventaire d'un mobilier diversifié, issu des collections publiques et privées. / Packaging food products, pharmaceuticals, and cosmetics to store them and transport them has always been a necessity for humans, both as consumers and merchants. This study, which deals with both history and archeology, highlights the major role played by glass, in Provence, in the 18th and 19th centuries, as a packaging quality method. Since Antiquity, and until the present day, luxury products, fine wines, delicate olive oils, and perfumes have been protected and emphasized through their glass packaging. It is the ideal material because it has all of the necessary physical and chemical properties to become functional and aesthetic. When Provence set out, in the early decades of the 18th century, in merchant conquest of the seas, it had an economy based on the transformation of local or imported agricultural goods. The manufacture of packaging then saw a considerable rise in Provence tied to this economy. Glass containers were then exported throughout the world, by sea, thanks to the combined action of favorable factures: the international reputation of the port of Marseille as well as the technical progress tied to the adoption of a new energy source : coal extraction. Influenced by the example of other regions, both French and European, Provencal glassworks underwent a notable metamorphosis which led to the gradual abandonment of forest glasshouse for port locations. Written and iconographic sources constitute a large part of our documentation supplemented by field sources. These are mainly tied to the discovery and recent study of shipwrecks as well as the survey of a diversified archeological inventory, derived from public and private collections.
1515

Fonctionnalisation et caractérisatin de films bioactifs à base d'HPMC : influence de l'introduction d'antioxydants sur les propriétés des films et la conservation des aliments / Functionalization and Characterization of Bioactive Films Based on HPMC : Influence of Antioxidants Inclusion on Films Properties and Food Preservation

Akhtar, Muhammad Javeed 13 September 2012 (has links)
La fonctionnalisation d'emballages biodégradables avec des antioxydants naturels est l'une des techniques prometteuses pour améliorer la conservation des aliments, diminuer la quantité de conservateurs chimiques utilises, protéger la dégradation aromatique des produits et ainsi conserver une meilleure qualité globale. Le contrôle du relargage de ces composés actifs de l'emballage vers l'aliment permet d'étendre l'efficacité de la fonctionnalisation en libérant progressivement les antioxydants à la surface de l'aliment. L'objectif global de ce travail était de fonctionnaliser le polymère HPMC afin de produire un film d'emballage coloré à activité antioxydante et d'évaluer son aptitude à servir d'emballage actif. Tout d'abord, des films d'HPMC contenant différents colorants synthétiques comme le bleu, le vert, le jaune, le rouge et le blanc ont été testés afin de déterminer la couleur la plus adaptée pour le contrôle de la photo-oxydation de produits gras. Ensuite, la couleur rouge synthétique, montrant un maximum de contrôle contre la photo-oxydation, a été remplacée par des composés actifs naturels de même couleur. Ces composés provenaient soit d'un mélange d'extraits de betterave et de carottes pourpres, d'un mélange de bétalaïnes soit d'un mélange d'anthocyanes. Le mode d'incorporation de ces composés actifs dans la matrice d'HPMC, leurs effets sur les propriétés thermiques, mécaniques, barrière et structurales des films ont été étudiés. Les résultats ont montré que l'intégration de ces différents composés actifs naturels a permis d'améliorer les propriétés des films. Les composés actifs utilisés ont la capacité de contrôler le photo-vieillissement de la matrice polymérique et que l'HPMC est un bon candidat pour incorporer ces molécules et permettre le contrôle de la dégradation de produits alimentaires riches en lipides / Biodegradable packaging functionalized with natural antioxidants is one of the promising techniques to enhance foods shelf-life, lower use of preservatives in food formations, higher protection of flavours and higher food qualities. Controlled release of these bioactive compounds from packaging to food surface provides longer food stability by continuously librating antioxidants at food surface. The overall objective of the present work was to functionalize the HPMC polymer as colored antioxidant packaging and investigate its suitability as active packaging for unsaturated lipids. Firstly, HPMC films containing different synthetic colours like blue, green, yellow, red and white were tested to chose a suitable color having control against photo-oxidation. Secondly, red synthetic color (showing maximum control against pho-oxidation) was replaced by natural active red compounds including "natural red color" (beetroot extract + purple carrot extract), betalains and anthocyanins to produce bioactive food packaging. Mode of incorporation of these active compounds in HPMC matrix and also their potential effects on thermal, mechanical, barrier and structural properties of films were investigated. Controlled release kinetics, antioxidant capacity and light stability of bioactive compounds in HPMC films were also investigated. The overall results showed that successful incorporation of different natural active compounds have capability to improve film properties. The active compounds under discussion have ability to control photo ageing of polymer matrix and HPMC has the capability for being a suitable carrier for antioxidant active packaging for some food products
1516

Étude des interactions physico-chimiques entre les préparations parentérales et un nouveau conditionnement primaire utilisable en unité de préparation centralisée, le flacon Crystal® / Physicochemical interaction study between parenteral products and Crystal® vial, a new primary packaging usable in centralized intravenous additive services

Feutry, Frédéric 08 November 2016 (has links)
La centralisation de la préparation des médicaments injectables à la pharmacie permet d’assurer un haut niveau de qualité mais nécessite une stabilité du médicament dans le conditionnement choisi et une capacité de production suffisantes. Aseptic Technologies a développé un système de remplissage automatisé de conditionnement primaire utilisant un flacon en copolymères d’oléfines cycliques (COC) clos, stérile et prêt à l’emploi appelé « flacon Crystal® ». Ce flacon est rempli à travers le bouchon et est re-scellé par laser, réduisant ainsi le risque de contamination microbiologique.Nous avons évalué les risques liés à l’utilisation du flacon Crystal® :• Le risque de sorption est corrélé à la lipophilie de la substance conditionnée. Pendant 3 mois, nous avons évalué l’évolution de la concentration de 8 molécules cytotoxiques (de coefficients de partage octanol/eau différents) par CLHP/MS. Une méthodologie identique a permis le suivi des concentrations, pendant 24 heures de 3 molécules dérivées du platine par RMN.• Concernant le risque de perméation, nous avons évalué l’évolution des concentrations en phénol et métacrésol dans une solution à 1UI/mL d’insuline conditionnée dans des flacons Crystal® conservés droits et retournés pendant 50 jours par CLHP/UV. Deux formulations différentes de bouchons ont été testées.• Les solutions de pH extrêmes peuvent conduire à la présence de particules dans la solution injectable. L’impact sur la contamination particulaire du conditionnement de ces solutions dans les flacons Crystal® a été étudié et les particules caractérisées.• Les plastifiants peuvent migrer du conditionnement primaire vers la préparation parentérale. Après extraction par reflux à l’isopropanol sur le corps en COC et le bouchon en élastomère, les éventuels plastifiants ont été identifiés et dosés par RMN.Enfin, les stabilités de solutions de céfuroxime, midazolam et noradrénaline conditionnées en flacon Crystal® ont été déterminées et comparées à la seringue en polypropylène (PP).Les concentrations moyennes des 8 molécules cytotoxiques étaient comprises entre 90% et 110% à J62 sans corrélation avec le coefficient de partage. L’absence d’interaction a aussi été démontré pour le carboplatine et l’oxaliplatine par RMN. La précision de la quantification par RMN du cisplatine n’était pas suffisante.Il existe un risque de perméation du métacrésol lors du stockage à 25°C/60%RH pendant 50 jours (perte de 19,7% et de 20,3% pour les flacons Crystal® droits et retournés respectivement). La seconde formulation du bouchon permet de maîtriser le phénomène (perte de 2,6% à J50).Une contamination particulaire importante a été observée lors du conditionnement d’une solution basique et d’un contact avec le bouchon pendant 7 jours (6820 particules 3; 10µm dans un flacon Crystal® de 20mL) Les particules sont fibreuses et composées essentiellement de molécules inorganiques.Les analyses RMN mettent en évidence la présence de plastifiants dans le corps en COC et le bouchon à des concentrations largement en-dessous de la limite de 1000µg/g définie par la réglementation REACH.La solution de céfuroxime (1mL à 10mg/mL) était stable 365 jours à -20°C. Les solutions de midazolam (50mL à 1mg/mL) et de noradrénaline (20mL et 50mL à 0,2mg/mL ; 50mL à 0,5mg/mL) étaient stables 365 jours à 5°C. Des résultats similaires ont été obtenus lors de la conservation en seringue PP.Les flacons Crystal® ne sont pas sujets aux phénomènes de sorption. Il n’y a pas de risque de migration de plastifiants. Le risque de perméation du métacrésol est contrôlé par l’utilisation du nouveau bouchon. Le conditionnement de solutions basiques doit être surveillé. Les solutions de céfuroxime (à -20°C), de midazolam et de noradrénaline (à 5°C) sont stables 1 an. Par rapport à la seringue PP, le flacon Crystal® pourrait être préféré de par son système de remplissage aseptique automatisé ainsi que pour des considérations logistiques, en particulier le gain de place. / Centralized preparation of parenteral products in the pharmacy can ensure a higher quality but requires a stability of the drugs in the chosen primary packaging and a sufficient production capacity. Aseptic Technologies has developed an automated primary packaging filling system using a closed, sterile and ready-to-use cyclic olefin copolymer vial called ‘‘Crystal® vial’’. This vial is filled through the elastomeric septum and then immediately re-sealed by laser, thus reducing the risk of microbial contamination.We have evaluated risks linked to the use of Crystal® vials:- Sorption risk is correlated with substance lipophilicity. During 3 months, we have evaluated concentration evolution of 8 cytotoxic drugs (with different water/octanol partition coefficients) by HPLC/MS. Same methodology was used to measure concentration evolution of 3 platinum-derived drugs by NMR during 24 hours.- About the permeation risk, we have evaluated concentration evolution of phenol and metacresol in a 1UI/mL insulin solution during 50 days by HPLC/UV in Crystal® vials stored upright and upside down. Two stoppers formulations exist and were tested.- Extreme pH solutions can lead to the presence of particles in the parenteral product. Impact of these solutions in Crystal® vials on particles contamination was studied and particles characterized.- Plasticizers may migrate from the primary packaging to the parenteral products. After isopropanol reflux extraction on the COC body and thermoplastic elastomer stopper, potential plasticizers were identified and quantified using NMR.Finally, stabilities of ready-to-use cefuroxime, midazolam and noradrenaline solutions in Crystal® vials were determined and compared to polypropylene syringes.The 8 cytotoxic drugs mean concentrations were between 90% and 110% at day 62 with no correlation with partition coefficient. Lack of interactions was demonstrated too for the oxaliplatin and carboplatin solution by NMR. Accuracy of NMR cisplatin quantification was not sufficient.Studies performed on preservatives highlighted a metacresol permeation risk during storage at 25°C/60%RH for 50 days (loss of 19.7% and 20.3% respectively for Crystal® vials stored upright and upside down). Use of the second formulation stopper allowed a large decrease of permeation (loss of 2.6% at day 50).An important particles contamination was observed only with extrem alkaline pH and contact with the stopper (6820 particles 10µm in a 20mL Crystal® vials stored upside down during 7 days). Particles are fibrous and essentially composed by non-organic substances.NMR analysis highlighted presence of plasticizers in both COC body and elastomer stopper but concentrations were below the 1000µg/g threshold described by the REACH regulation.Cefuroxime solution (1mL at 10mg/mL) was stable 365 days at -20°C. Midazolam solution (50mL at 1mg/mL) and noradrenaline solution (20mL and 50mL at 0.2mg/mL ; 50mL at 0.5mg/mL) were stable 365 days at 5°C. Same results were achieved in polypropylene syringes.Crystal® vials were not subject to sorption phenomena. There was no risk of plasticizer migration. Metacresol permeation risk was controlled using the new stopper. Packaging of alkaline solution must be monitored. Solutions of cefuroxime (-20°C), midazolam and noradrenaline (5°C) are stable 1 year. In regards to storage in polypropylene syringes, Crystal® vials could be prefered for their automated aseptic filling process and for logistic considerations particularly taking into account the space gains.
1517

Returlådan som försvann : En studie med syfte att minska saldoavvikelser av returlådor mellan ICAs centrallager och butiker

Posko, Alen, Andersson, Jim, Bergman, Jakob January 2019 (has links)
Title: The disappearing crate Context: Return logistics is an often forgotten but essential part of a company’s supply chain. As growing supply chains become increasingly complex, increased demands are placed on efficient logistics to create a competitive advantage over other parties on the market. ICA Sweden is currently using returnable packaging containers (RPCs) from Svenska Retursystem for transporting goods to their stores. The goods are sent via pallets and returnable packaging containers from a central warehouse or an external supplier. Empty packaging are then sent back to Svenska Retursystem. Each time a RPC changes hands, a debit fee is charged. When the RPC changes process owners, they transfer the debit fee to the next operator in the flow. If there is a loss of returnable packaging containers between two operators, a cost is incurred on this operator. The stores are charged through a so-called logistics cost, which can amount to about 0.7-0.9% of the stores' annual turnover. Purpose: The purpose of this study is to map the logistics process between the central warehouse and the stores and identify deficiencies in the process. Furthermore, the purpose of the study is to develop improvement proposals to reduce the negative balance of returnable packaging containers and reduce logistics costs for the stores. Method: The study has a comparative design of qualitative nature that adopts a critical realism approach. The research approach is deductive with a theoretical frame of reference as a starting point for the empirical material. Furthermore, the empirical material has been analyzed using pattern comparison. Results: The study has identified a number of different reasons why there may be a negative balance of returnable packaging containers at many ICA stores. Broadly speaking, we concluded that the problem stems from returnable packaging containers not being traceable. Human error throughout the process can also cause a mismatch of the administrative and physical flows. Improvement measures such as working with Lean, 5S, introducing RFID technology and investing in own trucks are discussed. / Titel: Returlådan som försvann Bakgrund och problemdiskussion: Returlogistik är en ofta glömd men likväl en viktig del av ett företags försörjningskedja. I takt med att växande försörjningskedjor blir alltmer komplexa ställs också ökade krav på en effektiv logistik för att skapa en konkurrensfördel gentemot andra aktörer på marknaden. ICA Sverige använder sig i dagsläget av returlådor från Svenska Retursystem för transport av varor till sina butiker. Varorna skickas bland annat via pall och returlådor till butikerna från ett centrallager eller en extern leverantör. Tomgods och tomemballage skickas sedan tillbaka till Svenska Retursystem. Hos varje aktör i ledet av de som använder returlådan debiteras en pantavgift. När returlådan byter processägare debiterar de nästa aktör i flödet. Sker ett bortfall av returlådor mellan två aktörer, uppstår en kostnad för denna aktören. Butikerna debiteras genom en så kallad logistikkostnad som kan uppgå till ca 0,7-0,9% av butikernas årliga omsättning. I dagsläget upplever många ICA butiker detta problem. Syfte: Syftet med denna studien är att kartlägga logistikprocessen mellan centrallager och butik samt identifiera brister i processen. Vidare är syftet med studien är att ta fram förbättringsförslag för att minska felsaldon och reducera logistikkostnader för butikerna. Metod: Studien har en jämförande design av kvalitativ art som antar ett kritiskt realism synsätt. Forskningsansatsen är deduktiv med en teoretisk referensram som utgångspunkt till det empiriska materialet. Datan för det empiriska materialet grundar sig på primärdata insamlat via semi-strukturerade intervjuer. Vidare har det empiriska materialet analyserats med hjälp av mönsterjämförelse. Slutsats: Studien har identifierat ett antal olika anledningar till varför det kan uppstå ett negativt saldo av returlådor hos många ICA butiker. I stora drag handlar det om att returlådorna inte kan spåras. Orsaker som mänskliga fel genom processen kan orsaka att det administrativa och fysiska flödet inte stämmer överens med varandra. Förbättringsåtgärder som att arbeta med 5S, införa RFID teknologi och investering i egna lastbilar diskuteras.
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O impacto do marketing "verde" nas decisões sobre embalagens das cervejarias que operam no Brasil / The impact of "green" marketing on packaging decisions in the beer industry in Brazil

Palhares, Marcos Fruet 15 December 2003 (has links)
Nos últimos anos, tem ganhado importância o debate sobre a preservação ambiental. Para responder às crescentes demandas do governo, traduzidas em uma legislação cada vez mais rigorosa, e dos consumidores, expressas em suas preferências no momento de compra, as empresas vêem-se obrigadas a observar cuidadosamente seu desempenho ambiental. Às vezes, contudo, temem-se eventuais incompatibilidades entre ações corporativas orientadas ecologicamente e aquelas direcionadas economicamente. Esta dissertação concentra suas atenções em embalagens, por serem estas identificadas, muitas vezes, com problemas ambientais, especialmente aqueles relacionados com a questão do lixo urbano. Partindo da análise de três casos da indústria cervejeira no Brasil, procurou-se identificar como – e se – a dimensão “verde" tem afetado as decisões sobre embalagem nas empresas de bens de consumo. Recorrendo à bibliografia produzida na área de marketing “verde", comportamento “verde" do consumidor e desenvolvimento sustentável, este trabalho mostra que ações “ambientalmente corretas" não são necessariamente incompatíveis com o bom desempenho econômico das empresas. Mais que isso, evidencia que o uso de ferramentas como a contabilidade ambiental, a análise de ciclo de vida e a logística reversa podem auxiliar na obtenção de vantagem competitiva. / In recent years, the debate about environmental preservation has gained importance. In order to respond to growing demands from the government, in the form of an ever more stringent legislation, and from the consumers, expressed by their preferences in buying situations, companies see themselves forced to watch carefully their environmental performance. Sometimes, though, it is feared that there are trade-offs between environmentally and economically oriented corporate actions. This dissertation puts packaging in the spotlight, because packages are, very often, closely identified with environmental problems, especially those related to urban waste issues. From the analysis of three cases in the Brazilian beer industry, it is sought here to identify how – and if – the “green" dimension has affected packaging decisions in consumer goods industries. Referring to bibliography on “green" marketing, “green" consumer behaviour, and sustained development, this research shows that “environmental correctness" and good economic performance are not necessarily antagonistic goals. More than that, it shows that the use of tools such as environmental accountability, life cycle assessment, and reverse logistics can help companies to obtain competitive advantage.
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Técnicas de conservação pós-colheita para cenoura roxa recém-introduzida no Brasil / Postharvest conservation techniques for purple carrot newly introduced in Brazil

Berno, Natalia Dallocca 29 November 2018 (has links)
O cultivo da cenoura (Daucus carota L.) se dá em diversas regiões do mundo, com produção anual ultrapassando 35 milhões de toneladas. Cenouras roxas foram recentemente introduzidas no Brasil e tem disponibilidade restrita, devido ao plantio ainda em fase de expansão. Dessa forma, essa hortaliça é novidade tanto para consumidores quanto para produtores. As práticas pós-colheita ainda são pouco estudadas e requerem mais conhecimento para viabilizar o armazenamento e ter um produto com qualidade físico-química e nutricional. Assim, o objetivo do presente trabalho foi estudar diferentes tecnologias pós-colheita para cenoura roxa recém-introduzidas no Brasil. Primeiramente, foram estudadas diferentes condições de armazenamento e suas implicações na qualidade de cenouras roxas. Os resultados mostraram que as perdas estão diretamente relacionadas ao aumento da temperatura de armazenamento, ou seja, quanto maior a temperatura, maiores são as perdas qualitativas e quantitativas. A condição ambiente (25°C e 70% UR) proporciona aumentos dos processos metabólicos, provocando maiores perdas, na aparência e nos compostos bioativos presentes. Cenouras mantidas a 2°C apresentaram vida útil de 60 dias e mantiveram a qualidade físico-química e nutricional, com menores perdas dos compostos fenólicos e polifenóis e aumento de antocianinas, flavonóis e da capacidade antioxidante, sendo essa a temperatura mais indicada para o armazenamento de cenouras roxas. Após definida a temperatura de armazenamento, cenouras foram armazenadas em diferentes atmosferas modificadas geradas por diferentes embalagens de forma a identificar a que resulte em manutenção da qualidade de cenouras roxa no armazenamento. O uso de atmosfera modificada em cenouras roxas inibiu perdas por murchamento e resultou em maior manutenção da aparência e dos aspectos bioquímicos, além de prolongar a vida útil. Em cenouras não embaladas foi verificado alto índice de murchamento e de perda de massa, com durabilidade de apenas 15 dias, e menores concentrações de compostos bioativos. Concentrações de O2 entre 11% e 12% e de CO2 a 0,5% são indicadas para o armazenamento prolongado de cenouras roxas em embalagens de atmosfera modificada. Em seguida, foi avaliado o uso de diferentes concentrações de revestimentos a base de quitosana e cera de carnaúba, na conservação de cenouras roxas. O uso de recobrimentos comestíveis em cenoura roxa se mostrou eficiente como técnica pós-colheita para preservação da qualidade comercial. Recobrimento a base de quitosana a 3%, aliada a alta umidade relativa e a baixa temperatura durante o armazenamento, é mais eficiente na manutenção da qualidade de cenouras roxas e proporciona aumento da vida útil em 15 dias, em relação ao controle. Os resultados evidenciam a importância de conhecer a fisiologia pós-colheita e de aplicar as boas práticas, principalmente aquelas vinculadas à redução do metabolismo vegetal, como as tecnologias estudadas. Tais resultados poderão ser prontamente aplicados pelos produtores, a fim de prolongar a vida útil dessa hortaliça recém-chegada ao mercado brasileiro. / The cultivation of carrots (Daucus carota L.) occurs in several regions of the world, with annual production exceeding 35 million tons. Purple carrots have recently been introduced in Brazil and have restricted availability due to planting still in expansion. Thus, this vegetable is new for consumers and producers. Postharvest practices are still poorly studied and require more knowledge to enable storage and have a product with physical-chemical and nutritional quality. In this way, the objective of the present work was to study different postharvest technologies for carrot newly introduced in Brazil. First, different storage conditions and their implications on the quality of purple carrots were investigated. The data showed that the losses are directly related to the increase of the storage temperature, that is, the higher temperature induce greater qualitative and quantitative losses. Ambient conditions (25°C and 70% RH) provide increases in metabolic processes, causing greater losses in appearance and bioactive compounds present. Carrots storage at 2°C, besides having a longer shelf life (60 days), maintained the physical-chemical and nutritional quality, with lower losses of phenolic compounds and polyphenols and increase of anthocyanins, flavonols and antioxidant capacity. That way, this is the best temperature for storage of purple carrots. With the storage temperature defined, it was aimed to study different modified atmospheres packaging (MAP) and to identify the one that results in greater maintenance of quality of purple carrots in storage. The MAP in purple carrots inhibited wilting losses and resulted in greater maintenance of appearance and biochemical aspects, as well as prolonged shelf life. In unpackaged carrots, a high wilting index and a loss of fresh weight were observed, with a durability of only 15 days, and lower concentrations of bioactive compounds. Concentrations of O2 between 11% and 12% and CO2 at 0.5% are indicated for the prolonged storage of purple carrots in MAP. Then, the use of different concentrations of chitosan and carnauba wax coatings in the conservation of purple carrots was evaluated. The use of edible coatings in purple carrots is a efficient postharvest technique for the preservation of commercial quality. The coating of 3% chitosan, combined with high relative humidity and low temperature during storage, is more efficient to maintain the quality of purple carrots and increases shelf life by 15 days compared to uncoating carrots. The results showed the importance of knowing postharvest physiology and applying good practices, especially those related to the reduction of plant metabolism, such as the technologies studied. The results could be readily applied by the producers, for extending the shelf life of the newly introduced vegetable to the Brazilian market.
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Avaliação dos efeitos da radiação por feixe de elétrons na resistência de embalagens a Lasioderma serricorne, Plodia interpunctella e Sitophilus zeamais / Radiation effects evaluation for electrons sheaf in packages resistance in a Lasioderma serricorne, Plodia interpunctella and Sitophilus zeamais

Alves, Juliana Nazaré 16 August 2011 (has links)
As pragas de produtos armazenados constituem um problema para o homem, depreciando produtos e causando prejuízos econômicos. Dentre estas pragas temos o Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) e Plodia interpunctella (H. 1813) conhecidos por infestar produtos armazenados como: grãos, farelos, farinhas, café, fumo, frutas secas e especiarias. Essas pragas perfuram e adentram as embalagens, ovipositando sobre o substrato. Neste contexto a embalagem desempenha um papel fundamental, impedindo o contato e proliferação de pragas no produto acondicionado. Assim, para proteger o produto acondicionado e prolongar a sua vidaútil a embalagem deve apresentar boa resistência mecânica à tração e à perfuração, boa selabilidade, boas propriedades de barreira e não transferir odores nem sabores estranhos ao produto acondicionado. A radiação ionizante pode causar mudanças estruturais nos materiais poliméricos de embalagens, essas mudanças são causadas pelos processos de cisão e reticulação das cadeias poliméricas. Estes são processos concorrentes e a predominância de um sobre o outro depende da estrutura química do polímero, das condições da irradiação e de fatores específicos do material que irá absorver a energia. Este trabalho teve o objetivo de avaliar as mudanças nas propriedades mecânicas de estruturas de embalagem utilizadas para armazenar granola, barra de cereais e macarrão, bem como suas resistências a perfuração por L. serricorne, P. interpunctella e S. zeamais, quando submetidas a radiação por feixe de elétrons. Na metodologia foram utilizadas cinco estruturas de embalagem comercialmente utilizadas para armazenar granola, barra de cereais e macarrão compostas por (Polipropileno bi-orientado metalizado/Polipropileno bi-orientado coextrusado - BOPPmet/BOPP 50 &mu;m), (Polipropileno bi-orientado/Polipropileno - BOPP/PP 50 &mu;m), Poli(tereftalato de etileno) metalizado/Polipropileno bi-orientado coextrusado - PETmet/BOPP 32 &mu;m), Poli(tereftalato de etileno)/Polipropileno - PET/PP1 72 &mu;m) e Poli(tereftalato de etileno)/Polipropileno - PET/PP2 32 &mu;m). As estruturas de embalagens foram submetidas à doses de radiação entre 0, 10, 20 e 60 kGy, em um acelerador de elétrons de 1,5 MeV, 25 mA e 37,5 kW, à taxa de dose de 11,22 kGy/s, temperatura ambiente e presença de ar. Oito dias, 2 meses e 6 meses após as irradiações foram realizados ensaios mecânicos de resistência a tração e elongação na ruptura, resistência da selagem e resistência à perfuração, todos com base nas suas respectivas normas ASTM [35]. Os ensaios de perfuração por insetos foram realizados em sala climatizada, onde amostras irradiadas nas doses de 0, 10, 20 e 60 kGy foram seladas contendo 40 g de granola, 40 g de macarrão e barra de cereais em número de nove por ensaio, e divididas igualmente em três caixas plásticas teladas por dose estudada. Em cada caixa foram adicionados 20 adultos de cada inseto em por 60 dias, quando as embalagens foram avaliadas para verificação de possíveis perfurações. As diferenças entre os resultados das amostras foram estatisticamente avaliados pelo método ANOVA (p<0,05). Os resultados mostraram que quanto à resistência a perfuração por L. serricorne, P. interpunctella e S. zeamais as estruturas poliméricas avaliadas apresentaram baixa resistência à perfuração por insetos antes e após o tratamento. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) e PET/PP2 (32 &mu;m) apresentaram perdas significativas nas estruturas nas propriedades mecânicas estudadas. O BOPP/PP (50 &mu;m) apresentou o melhor conjunto de respostas nas propriedades mecânicas ao tratamento por radiação com feixe de elétrons em doses de até 10 kGy. Dentre as propriedades mecânicas avaliadas a selagem foi a mais afetada pela radiação ionizante, tendo apresentado, em geral, perdas crescentes com a dose de radiação. / The plagues of stored products consist of a man problem, depreciating products and causing economical damages. Among these curses we have Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) and Plodia interpunctella (H. 1813) known by infesting stored products as: grains, brans, flours, coffee, tobacco, dried fruits and spices. These curses perforate and penetrate the packages, ovipositing over the substratum. In this context the package plays a fundamental part, preventing the contact and curses proliferation in the packed product. So, to protect the packed product and to prolong its shelf life, the package should have good mechanical resistance to tension and perforation, good sealing, good barrier properties and should not transfer odors nor strange flavors to the packed product. The ionizing radiation can cause structural changes in polymer packages, these changes are caused by the scission processes and reticulation of the polymers chains. These are concurrent processes and the predominance of one over the other depends on the chemical structure of the polymer, the irradiation conditions and specific factors of the material that will absorb the energy. This work had the objective to evaluate the changes in mechanical properties of package structures used to store granola, cereal bar and pasta, as well as its resistance to perforation by L. serricorne, P. interpunctella and S. zeamais, when submitted to electrons sheaf radiation. In this methodology were used five structures of commercially utilized packages to store granola, cereal bar and pasta composed by (Polypropylene bi-oriented metallic/Polypropylene bi-oriented coextruded - BOPPmet/BOPP 50 &mu;m), (Polypropylene bi-oriented/Polypropylene - BOPP/PP 50 &mu;m), Poli (ethylene terephthalate) metallic/Polypropylene bi-oriented coextruded - PETmet/BOPP 32 &mu;m), Poli (ethylene terephthalate) /Polypropylene - PET/PP1 72 &mu;m), Poli (ethylene terephthalate)/Polypropylene - PET/PP2 32 &mu;m). The structures of packaging were submitted to radiation doses between 0, 10, 20 and 60 kGy, in one electron accelerator of 1,5 M and V, 25 mA and 37,5 kW, dose tax of 11,22 kGy / s, room temperature and air presence . Eight days, Two and Six months after irradiations, mechanical resistance experiment were accomplished to tension and elongating in rupture, sealing resistance and perforation resistance, all based in respective ASTM norms. The perforation experiment by insects were realized in an acclimatized room, where irradiated samples in doses of 0, 10, 20 and 60 kGy were sealed containing 40 g of granola, 40 g of pasta and cereal bar in number of nine by experiment, and equally divided in three plastic screened boxes by studied dose. In each box 20 adults of each insect were added in for 60 days, when the packages were evaluated to verify possible perforations. The differences between the sample results were statistically evaluated by ANOVA (p<0.05). The results showed that concerning the perforation resistance by L. serricorne, P. interpunctella and S. zeamais the polymeric structures evaluated showed low resistance by insects perforation before and after the treatment. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) and PET/PP2 (32 &mu;m) structures showed significant losses in mechanical properties studied. The BOPP/PP (50 &mu;m) showed the best set of answers in mechanical properties to the radiation treatment with electrons sheaf up to 10 kGy doses. Among the mechanical properties evaluated, sealing was the most affected by ionizing radiation, has shown, in general, increasing losses with radiation dose.

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