Édition de : Thèse 3e cycle : Etudes latines : Paris 4 : 1986. / Bibliogr. p. [225]-228 Notes bibliogr. Index.

Made available in DSpace on 2016-08-03T12:18:59Z (GMT). No. of bitstreams: 1 Elcio V S Mendonca.pdf: 938537 bytes, checksum: 5c2862b0c25ee6bf58d1c47c44fb8074 (MD5) Previous issue date: 2012-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Theology of Zion by the tradition of sons of Korah is somewhat curious. Tease is entertaining the idea of a canaanite influence in the Theology of Zion. There isn t denying that fact, because Psalm 48 seems to really have this influence. It is a canaanite influence and also the traditions of South Judahite. This research aims analyze the existing Theology of Zion in Jerusalem and presented in Psalm 48. This is to arrive at an answer about the influence that the sons of Korah may been the canaanite religion, using elements of canaanite myths in the composition of Psalm 48 and other psalms of this collection. Terms like Saphon, sea, death and Mount Zion, and concepts like mythology, sacred mountain, end of the world, Olympus, etc., make us think that really wanted to override the canaanite myths presenting a new reading from the faith in Yahweh. The sons of Korah had were North Israelite traditions, the cities where they lived were located in Ephraim, Manasseh and Dã. Some cities of Manasseh and Ephraim were canaanites cities. The kings of North were mostly promoter of the canaanite Religion. This was the environment where the sons of Korah lived and served your levitical minitstry. / A Teologia de Sião expressa pela tradição dos filhos de Corá é de certa forma curiosa. É implicante admitir a idéia de uma influência cananeia na Teologia de Sião. Não há como negar esse fato, pois o Salmo 48 parece realmente possuir esta influência. É uma influência cananeia e também das tradições do Sul judaíta. Esta pesquisa tem por objetivo analisar tal teologia de Sião existente em Jerusalém e apresentada no Salmo 48. Isto para chegar a uma resposta acerca da influência que os filhos de Corá podem ter sofrido da religião cananeia, ao utilizar elementos dos mitos cananeus na composição do Salmo 48 e de outros salmos de sua coleção. Termos como Safon, mar, morte, Monte Sião e outros, e conceitos como mitologia, montanha sagrada, extremidade do mundo, Olimpo, etc, fazem pensar que eles de fato queriam sobrepor os mitos cananeus apresentando uma nova leitura, a partir da fé em Javé. Os filhos de Corá possuíam tradição do Norte israelita. As cidades onde eles habitaram estavam situadas em Efraim, Manassés e Dã. Algumas cidades de Manassés e Efraim eram cananeias. Os reis do Norte eram em sua maioria promotores da religião cananeia. Este era o ambiente onde os filhos de Corá habitaram e cumpriram seu ministério levítico.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / factor responsible for climate change worldwide. In recent years, several research are intended to developing new methods and technologies to capture and separation CO2. The use of the adsorption method for separating CO2 is a promising alternative in view of the potential to reduce energy costs by eliminating aqueous solutions and providing capture and regeneration rates adequate. In this context, this paper presents the synthesis of composite type materials ZSM-12 / MCM-41 and ZSM-12 / MCM-48, seeking to combining the properties of the zeolitic material to the structural advantages of mesoporous materials, resulting in obtaining materials with high CO2 adsorption capacity. For this, the materials were synthesized by hydrothermal method and mechanosynthesis. The materials were characterized by XRD, absorption spectroscopy in the infrared, thermal analysis, adsorption-desorption analysis of N2 A 77 K, SEM and TEM. The CO2 adsorption capacity of these materials were investigated by gravimetric analysis. The results obtained from the characterization techniques showed that the synthesis methodology, used for desilication phase of ZSM-12, was efficient in obtaining a composite material with integrated micro and mesoporous phases. On the other hand, the results showed that by mechanosynthesis was possible to obtain materials formed by mixing between the micro and mesoporous phases. Also, comparing the results of adsorption CO2 the obtained composite materials by hydrothermal method with those obtained by mechanosynthesis it was concluded that the adsorption capacity is influenced by crystallinity and amount of the phase ZSM-12. The results showed from adsorption, in general, ZM48-75 samples, ZM41 A/MH R3 and ZM41-50 showed higher adsorption capacity than pure zeolitic and mesoporous materials, respectively. Thus, the composite materials of the type ZSM-12/ZSM-41 and MCM-12/MCM-48 are promising adsorbents for CO2 separation. / O aumento da concentração de dióxido de carbono na atmosfera é apontado como o principal fator responsável pelas mudanças climáticas em escala mundial. Nos últimos anos, várias pesquisas têm por finalidade o desenvolvimento de novos métodos e tecnologias para captura e separação de CO2. A utilização do método de adsorção para separação de CO2 é uma alternativa promissora, tendo em vista o potencial para reduzir os custos energéticos, eliminando soluções aquosas e proporcionando captura e taxa de regeneração adequadas. Nesse contexto, neste trabalho apresenta-se a síntese de materiais compósitos do tipo ZSM-12/MCM-41 e ZSM-12/MCM-48, visando combinar as propriedades do material zeolítico com as vantagens estruturais dos materiais mesoporosos, resultando na obtenção de materiais com elevadas capacidades de adsorção de CO2. Para isto, os materiais foram sintetizados pelo método hidrotérmico e por mecanosíntese. Os materiais obtidos foram caracterizados por DRX, espectroscopia de absorção na região do infravermelho, análise térmica, analise de adsorção-desorção de N2 A 77 K, MEV e TEM. A capacidade de adsorção de CO2 destes materiais foi investigadas através da análise gravimétrica. As técnicas de caracterização mostraram que a metodologia de síntese adotada via dessilicalização da fase ZSM-12 foi satisfatória na obtenção de um material compósito com as fases micro e mesoporosas integradas. Por outro lado, os resultados evidenciaram que através da mecanosíntese foi possível obter materiais formados pela mistura entre as fases micro e mesoporosas. Além disso, comparando-se os resultados de adsorção de CO2 dos materiais compósitos obtidos via método hidrotérmico com os obtidos via mecanosíntese foi possível concluir que a capacidade de adsorção é influenciada pela cristalinidade ou teor da fase ZSM-12. Considerando-se os resultados de adsorção apresentados, de maneira geral, as amostras ZM48-75, ZM41-A/R3-MH e ZM41-50, apresentaram maior capacidade de adsorção que os materiais zeolíticos e mesoporosos puros, respectivamente. Sendo assim, os materiais compósitos do tipo ZSM-12/MCM-41e ZSM-12/MCM-48 são promissores adsorventes para separação de CO2.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / factor responsible for climate change worldwide. In recent years, several research are intended to developing new methods and technologies to capture and separation CO2. The use of the adsorption method for separating CO2 is a promising alternative in view of the potential to reduce energy costs by eliminating aqueous solutions and providing capture and regeneration rates adequate. In this context, this paper presents the synthesis of composite type materials ZSM-12 / MCM-41 and ZSM-12 / MCM-48, seeking to combining the properties of the zeolitic material to the structural advantages of mesoporous materials, resulting in obtaining materials with high CO2 adsorption capacity. For this, the materials were synthesized by hydrothermal method and mechanosynthesis. The materials were characterized by XRD, absorption spectroscopy in the infrared, thermal analysis, adsorption-desorption analysis of N2 A 77 K, SEM and TEM. The CO2 adsorption capacity of these materials were investigated by gravimetric analysis. The results obtained from the characterization techniques showed that the synthesis methodology, used for desilication phase of ZSM-12, was efficient in obtaining a composite material with integrated micro and mesoporous phases. On the other hand, the results showed that by mechanosynthesis was possible to obtain materials formed by mixing between the micro and mesoporous phases. Also, comparing the results of adsorption CO2 the obtained composite materials by hydrothermal method with those obtained by mechanosynthesis it was concluded that the adsorption capacity is influenced by crystallinity and amount of the phase ZSM-12. The results showed from adsorption, in general, ZM48-75 samples, ZM41 A/MH R3 and ZM41-50 showed higher adsorption capacity than pure zeolitic and mesoporous materials, respectively. Thus, the composite materials of the type ZSM-12/ZSM-41 and MCM-12/MCM-48 are promising adsorbents for CO2 separation. / O aumento da concentração de dióxido de carbono na atmosfera é apontado como o principal fator responsável pelas mudanças climáticas em escala mundial. Nos últimos anos, várias pesquisas têm por finalidade o desenvolvimento de novos métodos e tecnologias para captura e separação de CO2. A utilização do método de adsorção para separação de CO2 é uma alternativa promissora, tendo em vista o potencial para reduzir os custos energéticos, eliminando soluções aquosas e proporcionando captura e taxa de regeneração adequadas. Nesse contexto, neste trabalho apresenta-se a síntese de materiais compósitos do tipo ZSM-12/MCM-41 e ZSM-12/MCM-48, visando combinar as propriedades do material zeolítico com as vantagens estruturais dos materiais mesoporosos, resultando na obtenção de materiais com elevadas capacidades de adsorção de CO2. Para isto, os materiais foram sintetizados pelo método hidrotérmico e por mecanosíntese. Os materiais obtidos foram caracterizados por DRX, espectroscopia de absorção na região do infravermelho, análise térmica, analise de adsorção-desorção de N2 A 77 K, MEV e TEM. A capacidade de adsorção de CO2 destes materiais foi investigadas através da análise gravimétrica. As técnicas de caracterização mostraram que a metodologia de síntese adotada via dessilicalização da fase ZSM-12 foi satisfatória na obtenção de um material compósito com as fases micro e mesoporosas integradas. Por outro lado, os resultados evidenciaram que através da mecanosíntese foi possível obter materiais formados pela mistura entre as fases micro e mesoporosas. Além disso, comparando-se os resultados de adsorção de CO2 dos materiais compósitos obtidos via método hidrotérmico com os obtidos via mecanosíntese foi possível concluir que a capacidade de adsorção é influenciada pela cristalinidade ou teor da fase ZSM-12. Considerando-se os resultados de adsorção apresentados, de maneira geral, as amostras ZM48-75, ZM41-A/R3-MH e ZM41-50, apresentaram maior capacidade de adsorção que os materiais zeolíticos e mesoporosos puros, respectivamente. Sendo assim, os materiais compósitos do tipo ZSM-12/MCM-41e ZSM-12/MCM-48 são promissores adsorventes para separação de CO2.

Bacillus amyloliquefaciens FZB42 ist ein grampositives Bodenbakterium. Es kann in der Rhizosphäre das Wachstum von Pflanzen fördern und durch die Produktion von Sekundärmetaboliten phytopathogene Organismen hemmen. Aus der Genomanalyse und den dazugehörigen Arbeiten war bekannt, dass Bacillus amyloliquefaciens FZB42 nicht-ribosomal je drei antimikrobielle Polyketide und Lipopeptide herstellt, sowie zwei Siderophore und das Dipeptid Bacilysin. Für Bacillus typische Lantibiotika oder große Bacteriocine wurden nicht gefunden. In dieser Arbeit wird erstmalig gezeigt, dass Bacillus amyloliquefaciens FZB42 auf ribosomale Weise antibakterielle Peptide herstellt. Zwei bisher unbekannte Bacteriocine, Amylocyclicin A und Plantazolicin, und deren dazugehörigen Gencluster konnten identifiziert und charakterisiert werden. Amylocyclicin A ist ein unmodifiziertes Peptid, dessen N- und C-Terminus kovalent verbunden sind. Es wurde der Gruppe I der zirkulären Bacteriocine zugeordnet, dessen Mitglieder sich durch schwache Homologie untereinander, aber durch wahrscheinlich ähnliche 3D-Strukturen auszeichnen. Die Masse beträgt 6381 Da und die Substanz ist stark aktiv gegen grampositive Bakterien. Das Biosynthesecluster umfasst sechs Gene für die Synthese, den Export, die Zyklisierung und die Immunität. Plantazolicin ist ein hydrophobes, stark modifiziertes Peptid aus der TOMM-Gruppe, einer Gruppe aus Microcin B17-ähnlichen Peptiden, die nach neueren Erkenntnissen verbreiteter ist, als bisher bekannt. Plantazolicin ist schwach aktiv gegen grampositive Bakterien und besitzt die Masse 1335 Da. Das Biosynthesecluster umfasst zwölf Gene, mit allen nötigen Genen für Synthese, Modifikation, Regulation, Immunität und Export. / Bacillus amyloliquefaciens FZB42 is a Gram-positive, plant-associated bacterium, which stimulates plant growth and produces secondary metabolites that suppress soil-borne plant pathogens. Five gene clusters direct the non-ribosomal synthesis of the cyclic lipopeptides surfactin, bacillomycin, fengycin, an unknown peptide and the iron-siderophore bacillibactin. Three gene clusters direct the non-ribosomal synthesis of the antibacterial acting polyketides macrolactin, bacillaene and difficidin; in addition to the non-ribosomal synthesis of the antibacterial dipeptide bacilysin. Genes involved in ribosome-dependent synthesis of lantibiotics and other peptides are scarce. Only two incomplete gene clusters directing immunity against mersacidin and subtilin were found. In this work two ribosomally synthesized antibacterial peptides, amylocyclicin A and plantazolicin, and their corresponding gene clusters were identified. Amylocyclicin A is a circular peptide with a mass of 6381 Da and strong activity against Gram-positive bacteria. Six genes are responsible for the synthesis, maturation, export and immunity of this peptide belonging to group I of circular bacteriocins. Plantazolicin is a strongly modified hydrophobic peptide bearing a molecular mass of 1,335 Da and displaying antibacterial activity toward closely related Gram-positive bacteria. Essential modification contains the incorporation of azole heterocycles, which derive from Cys, Ser, and Thr residues of the precursor peptide and addition of two methyl groups. Twelve genes are responsible for synthesis, modification, export and immunity of this peptide belonging to the TOMM group of thiazol/oxazol modified microcins.

The impact of a mandatory Part 48 training program on the health and safety knowledge level of newly employed inexperienced miners in Texas was studied. Part 48 training was defined by compliance with Mine Safety and Health Administration's (MSHA) mandatory health and safety training requirements. A two-group pretest, posttest research design was utilized. Group one individuals were newly employed inexperienced persons who received mandatory Part 48 training in accordance with MSHA guidelines. Group two subjects were newly employed inexperienced persons who worked for companies that were exempt from conducting a Part 48 training program. MSHA's health and safety knowledge inventory was utilized. A significant difference was found in the health and safety training program when compared with individuals who did not receive the training . A significant difference was also found in the posttest scores for eight of the ten subject areas of the MSHA health and safety knowledge inventory for persons who completed a Part 48 training program when compared to persons who did not receive the training . Analysis of gain scores resulted in significant differences in the same subject areas indicated by posttest scores. It was concluded that MSHA Part 48 did have a significant impact on the health and safety knowledge level of newly employed inexperienced miners. Additional implications noted relate to the impact of a Part 48 training program on accidents, productivity, absenteeism, turnover, job satisfaction and management styles; role of MSHA in miner training; development of new training materials; methods of training; and the evaluation of health and safety training programs.

L’IRM mammaire a une place prépondérante dans l’imagerie mammaire. Son utilisation plus large est limitée notamment par son coût et le nombre limité de machines. Nous avons travaillé sur plusieurs aspects de cette problématique. Dans un premier temps, nous avons modifié le positionnement en passant du procubitus au décubitus. Ceci a permis de montrer que le décubitus permettait une meilleure corrélation topographique des lésions avec l’échographie et était mieux toléré par les patientes. Dans un deuxième temps, nous avons étudié les facteurs de réduction du temps d’acquisition par l’intermédiaire des séquences à haute résolution temporelle et d’un protocole abrégé. Ces changements devraient permettre de faciliter l’accessibilité de l’IRM aux patientes, de réduire son coût tout en conservant les mêmes valeurs de sensibilité et spécificité que le protocole standard / Breast MRI has a prominent place in breast imaging. Its wider use is limited in particular by its cost and the limited number of machines. We have worked on several aspects of this problem. In a first step, we changed the positioning from procubitus to decubitus. This showed that the decubitus allowed a better topographic correlation of the lesions with the ultrasound and was better tolerated by the patients. In a second step, we studied the factors of reduction of the acquisition time via the sequences with high temporal resolution and an abbreviated protocol. These changes should make it easier for patients to access MRI, reduce costs while maintaining the same sensitivity and specificity values as the standard protocol

Avec une population mondiale vieillissante, de plus en plus de personnes sont à risque de présenter des pathologies pour lesquelles l’Imagerie par Résonance Magnétique (IRM) est une modalité de choix : ainsi, le nombre d’examens IRM est en constante augmentation. Les patients âgés étant par ailleurs une population davantage susceptible de recevoir une implantation de dispositifs médicaux (tels qu’un pacemaker ou une prothèse de hanche), la sécurité des patients implantés en IRM est primordiale. En effet, cet appareil d’imagerie médicale fait intervenir différents champs électromagnétiques pouvant interagir avec un implant métallique et donner lieu à des risques potentiels pour le patient. Si des normes de compatibilité existent aujourd’hui pour soumettre individuellement les dispositifs médicaux à des tests standardisés et assurer leur innocuité en environnement IRM, les interactions entre multiples dispositifs médicaux vis-à-vis des ondes électromagnétiques radiofréquence (et des dangers qui peuvent en résulter) sont un domaine complexe qu’il est nécessaire de comprendre. L’objet de cette thèse est d’étudier ces interactions sur plusieurs niveaux : interactions intra-dispositif, interactions inter-dispositifs et interactions entre dispositif et plusieurs antennes. Une méthode de prédiction d’échauffement a été proposée pour simplifier l’étude de larges gammes d’implants, suivant les variations de paramètres caractérisant les différentes parties au sein d’une prothèse. Des simulations électromagnétiques et thermiques, associées à des mesures expérimentales dans un environnement IRM clinique, ont permis de mettre en évidence des phénomènes de couplages entre deux implants simplifiés et d’introduire une nouvelle métrique pour les quantifier. Enfin, une étude multi-antennes a fourni des éléments de réponse à la question de la sécurité d’un patient implanté en présence de plusieurs antennes, dans une configuration semblable à celle des examens en routine clinique. Les travaux présentés dans cette thèse ont ainsi permis d’évaluer les interactions vis-à-vis de la radiofréquence de l’IRM en présence d’un ou plusieurs dispositifs médicaux et antennes, ouvrant plusieurs perspectives pour aller vers une IRM sûre pour tous / With an aging population worldwide, more and more persons are at risk of suffering from pathologies which are best diagnosed or monitored with Magnetic Resonance Imaging (MRI): thus, the number of MRI exams is constantly increasing. Moreover, elderly patients being likely to undergo a medical device implantation (such as a pacemaker or a hip prosthesis) the safety of implanted patient in MRI is crucial. The medical imaging technique involves indeed different electromagnetic fields which can interact with a metallic implant and lead to potential hazard for the patient. Even though compatibility guidelines exist today to subject individually medical devices to standardized tests and ensure their harmlessness in an MRI environment, the interactions between multiple medical devices with respect to radiofrequency electromagnetic waves (and to the hazards that may follow) are a complex research area that has to be understood. The aim of this thesis is to study these interactions on different levels: intra-device interactions, inter-devices interactions and interactions between a device and several antennas. A prediction method has been proposed to simplify the study of large range of implants, according to the variations of parameters characterizing the different parts of a prosthesis. Electromagnetic and thermal simulations, associated with experimental measurements in a clinical MRI environment, allowed to highlight a coupling phenomenon between two simplified implants and to introduce a new metric to quantify them. Finally, a multi-antenna study led to some insights to answer the question of the safety of an implanted patient with several antennas, in a configuration similar to a clinical routine exam. Thus, the research work presented in this thesis allowed to assess the interactions with respect to MRI radiofrequency in presence of one or several medical devices and antennas, opening new prospects towards a safe MRI for everyone

High mass loss rates in evolved stars make them the major contributors to recycling processed material back into the interstellar medium. This mass loss creates large circumstellar shells, rich in molecular material. This dissertation presents millimeter and submillimeter studies of the end stages of low mass and high mass stars in order to probe their molecular content in more detail. In low mass stars, the molecular material is carried on into the planetary nebula (PN) stage. Observations of CS, HCO⁺, and CO in planetary nebulae (PNe) of various post-asymptotic giant branch ages have shown that molecular abundances in these objects do not significantly vary with age, as previously thought. More detailed observations of the slightly oxygen-rich PN NGC 6537 resulted in the detection of CN, HCN, HNC, CCH, CS, SO, H₂CO, HCO⁺ and N₂H⁺, as well as numerous ¹³C isotopologues. Observations of the middle-aged PN M2-48 showed the presence of CN, HCN, HNC, CS, SO, SO₂, SiO, HCO⁺, N₂H⁺, and several ¹³C isotopologues. These observations represent the first detections of CS, SO, SO₂, and SiO in any planetary nebula. The implications of these observations are discussed. A 1 mm spectral survey of the supergiant star NML Cygni has been carried out with the Arizona Radio Observatory Submillimeter Telescope resulting in the observation of 102 emission features arising from 17 different molecules and 4 unidentified features. The line profiles observed in this circumstellar shell are asymmetric and vary between different molecules, akin to what has been seen in another supergiant, VY Canis Majoris. The non-LTE radiative transfer code ESCAPADE has been used to model molecular abundances in the various asymmetric outflows of VY Canis Majoris, showing just how chemically and kinematically complex these supergiant circumstellar envelopes really are.

Η κλασική Απεικόνιση του Μαγνητικού Συντονισμού (ΑΜΣ) βασίζεται στο φαινόμενο του πυρηνικού μαγνητικού συντονισμού όπου η κάθε λέξη ξεχωριστά μας βοηθάει να κατανοήσουμε ποια είναι η προέλευση αυτού του φαινομένου. Συγκεκριμένα, το μετρούμενο σήμα προέρχεται από τους πυρήνες των ατόμων της ύλης, η αλληλεπίδραση μεταξύ των οποίων είναι μαγνητική και το τελικό σήμα εκφρασμένο σε μορφή φασμάτων ή εικόνων λαμβάνεται χρησιμοποιώντας το φαινόμενο του πυρηνικού μαγνητικού συντονισμού. Στην κατηγορία της ποσοτικής ΑΜΣ (πΑΜΣ), όμως, μετράμε άμεσα τις ποσοτικές παραμέτρους από τις οποίες εξαρτώνται τα τελικά σήματα όπως χρόνους μαγνητικής αποκατάστασης, μοριακή διάχυση, pH, μικρο-ιξώδες κτλ. Η ρύθμιση και η βαθμονόμηση των παραμέτρων του τελικού μετρητικού συστήματος (σύστημα ΑΜΣ) παίζουν βασικό ρόλο στα τελικά αποτελέσματα των μετρήσεών μας. Για το λόγο αυτό είναι απαραίτητη η χρήση ειδικών ομοιωμάτων για τη βαθμονόμηση του μετρητικού συστήματος καθώς και για την αξιολόγηση και βελτιστοποίηση των μετρητικών μεθόδων. Τα ομοιώματα ελέγχου θα πρέπει να έχουν κάποια συγκεκριμένα βασικά χαρακτηριστικά, για να προσομοιάζουν όσο το δυνατόν καλύτερα τις μαγνητικά μετρούμενες παραμέτρους σε σχέση πάντα με εκείνες των ανθρωπίνων ιστών. Τέτοιες παράμετροι είναι κυρίως οι χρόνοι μαγνητικής αποκατάστασης (Τ1, Τ2, Τ2*) και η μοριακή διάχυση. Στα υλικά των ομοιωμάτων θα πρέπει να υπάρχει επιπλέον η δυνατότητα ανεξάρτητου ελέγχου των χρόνων μαγνητικής αποκατάστασης Τ1 και Τ2. Επίσης, θα πρέπει τα υλικά αυτά να έχουν φυσική και χημική σταθερότητα στο χρόνο και τέλος να παρασκευάζονται εύκολα και να είναι οικονομικά. Στην παρούσα εργασία παρασκευάστηκαν ειδικά ομοιώματα ενός πολυσακχαρίτη, της αγαρόζης, με πρόσμιξη μιας παραμαγνητικής ουσίας, του γαδολινίου (Gd-DTPA), σε 20 διαφορετικούς συνδυασμούς συγκεντρώσεων μεταξύ τους. Με βάση αυτά τα ομοιώματα μετρήσαμε τους χρόνους μαγνητικής αποκατάστασης Τ1, Τ2, Τ2* για οκτώ επαναλήψεις σε διάστημα τεσσάρων μηνών. Διαπιστώσαμε ότι η πιο αποτελεσματική ακολουθία για τη μέτρηση της Τ2 είναι σε μια ακολουθία πολλαπλών συμμετρικά επαναλαμβανόμενων Spin Echo (32 echo) με αρχική τιμή ΤΕ = 20ms. Με την χρήση της ακολουθίας αυτής καλύπτεται το μεγαλύτερο φάσμα μετρήσεων τιμών Τ2 για τους μαλακούς βιολογικούς ιστούς και επίσης τηρείται το 6 επιτρεπτό όριο του συντελεστή μεταβλητότητας για αυτόν τον τύπο των μετρήσεων (CV=±5%). Για τη μέτρηση της Τ1 εφαρμόσαμε δύο μεθόδους (Variable Flip Angle-VFA, Variable Time Inversion-VTI). Η πιο αποτελεσματική μέθοδος αποδείχθηκε η VTI. Η VFA υστερούσε στις μετρήσεις λόγω της αδυναμίας προσαρμογής των δεδομένων στην μαθηματική συνάρτηση περιγραφής των σημάτων λήψης Y(FA) = f (FA). Επιπλέον, διαπιστώσαμε ότι το παραμαγνητικό ιόν του γαδολινίου επηρεάζει την μέτρηση της Τ1 ανεξάρτητα από το μοριακό τύπο ή το είδος της χειλικής χημικής ένωσης στην οποία ανήκει. Τέλος, διαπιστώσαμε ότι σε όλες τις μετρήσεις η μεγαλύτερη ανομοιογένεια του τοπικού μαγνητικού πεδίου παρουσιάζεται στα πυκνά διαλύματα σε αγαρόζη και γαδολίνιο κυρίως λόγω της παραμαγνητικής ιδιότητας του γαδολινίου, η οποία επηρεάζει το τοπικό μαγνητικό πεδίο της μέτρησης. Μεγάλο συντελεστή μεταβλητότητας στις μετρήσεις της ανομοιογένειας του τοπικού μαγνητικού πεδίου παρουσιάζουν τα αραιά κολλοειδή διαλύματα και το νερό, διότι επηρεάζονται ευκολότερα από τις εξωτερικές επιδράσεις της μέτρησης (π.χ. θερμοκρασία) εξαιτίας της ασθενούς σύνδεσης μεταξύ των μορίων του υλικού τους. / The typical Magnetic Resonance Imaging (MRI) is based in the phenomenon of the nuclear magnetic resonance where each individual word, helps us understand its origin. Specifically, the measured signal is generated by the nucleus of the matter's atoms. The interaction of the latter is magnetic and the final signal is detected in the form of spectrum or images through the phenomenon of nuclear magnetic resonance. Nevertheless, in the field of quantitative MRI, we can measure quantitative parameters like magnetic relaxation time, molecular diffusion, micro-viscosity etc., on which the final signals depend. The adjustment and calibration of the parameters of the final metering systems (system MRI) are crucial for the final results. Therefore, it is essential to use special phantoms for the calibration of the metering system as well as for the valuation and optimization of the metering processes. The control phantoms need to have specific characteristics in order to simulate as much as possible the magnetically measured parameters with respect to the ones of the human tissues. Such parameters are mainly the magnetic relaxation times (T1, T2, T2*) and the molecular diffusion. The phantoms should also provide the option of individual testing of the magnetic relaxation times T1 and T2. Moreover, these materials should have the same physical and chemical stability in time and their production needs to be financially effective. In this paper, special agarose phantoms were produced, by mixing gadolinium, a paramagnetic substance, in 20 different concentrations. Based on these phantoms we measured 8 times the magnetic relaxation times Τ1, Τ2, Τ2* within a period of 4 months. We noted that the most effective sequence for measuring T2 is by symmetrically spin echo sequence with the initial time having the value of 20ms. Using this method, the widest range of T2 values is covered with regards to soft tissues. Additionally, the variation coefficient permissible figures for such measurements is respected (CV=±5%). In order to measure T1 we used two methods, Variable Flip Angle-VFA, Variable Time Inversion-VTI. The most effective one, was proven to be the VTI one. VFA method was presenting delays in the measurements due to the inability to adjust the data in the function of signal reception description Y(FA) = f (FA). Moreover, we discovered that the paramagnetic ion of gadolinium is affecting the measurement of T1 regardless the molecular type or the type of chemical ligand that this belongs to. Finally, we noted that throughout the experiments, the highest inhomogeneity of the local magnetic field is found in the dense solutions of agarose and gadolinium mainly due to the paramagnetic properties of gadolinium which affects the local magnetic field of the measurement. High variability factor of inhomogeneity of the local magnetic field demonstrated the dilute gels and water because of the poor connection between the molecules of their material.