Section of an Iconostasis Beam from the Monastery of Mount Sinai with Scenes from the Life of the Virgin

Μη διαθέσιμη περίληψηno abstrac

Study of the geological - geptechnical conditions along the Line 4 route of Athens Metro, Section: Faros - Maroussi

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Σχεδιασμός και Κατασκευή Υπόγειων Έργων”300 σ.Η παρούσα διπλωματική εργασία έχει ως θέμα τη «Διερεύνηση των γεωλογικών – γεωτεχνικών συνθηκών κατά μήκος της χάραξης της Γραμμής 4 του Μετρό Αθηνών, στο τμήμα Φάρος Ψυχικού – Μαρούσι». Σκοπός της εργασίας ήταν η αποσαφήνιση του γεωλογικού – γεωτεχνικού προσομοιώματος του υπεδάφους κατά μήκος της χάραξης του συγκεκριμένου τμήματος της νέας γραμμής που πρόκειται να κατασκευασθεί τα επόμενα χρόνια, η επισήμανση των κρίσιμων ή προβληματικών ζητημάτων που ενδέχεται να προκύψουν και η διατύπωση προτάσεων για την ορθή και ασφαλή αντιμετώπισή τους. Αρχικά, συλλέχθηκαν όλες οι διαθέσιμες γεωτεχνικές έρευνες που έχουν εκτελεσθεί στην ευρύτερη περιοχή του έργου καθώς και οι σχετικές υπάρχουσες βιβλιογραφικές πηγές. Στη συνέχεια έγινε επεξεργασία και παρουσίαση των γεωλογικών στοιχείων και ακολούθως έγινε η αξιολόγηση αυτών, η οποία περιελάμβανε την δημιουργία γεωλογικού χάρτη & γεωλογικής μηκοτομής κατά μήκος της χάραξης και διαχωρισμό επιμέρους υποτμημάτων βάσει κοινών γεωλογικών χαρακτηριστικών. Ακολούθως έγινε ψηφιακή καταγραφή και διαχείριση του συνόλου των στοιχείων που συγκεντρώθηκαν σε μία ενιαία γεωτεχνική βάση δεδομένων με αποτέλεσμα την συγκεντρωτική πινακοποίησή τους ανά κατηγορία και ανά διακριθείσα γεωτεχνική ενότητα. Η επεξεργασία των στοιχείων που συγκεντρώθηκαν σε Γεωγραφικό Σύστημα Πληροφοριών (G.I.S.) είχε ως αποτέλεσμα τη δημιουργία ψηφιακών χαρτών για την οπτικοποίηση σημαντικών πληροφοριών σε σχέση με το υπό μελέτη έργο. Επιπλέον εκτελέστηκε στατιστική επεξεργασία των αποτελεσμάτων των επιτόπου και εργαστηριακών δοκιμών ανά διακριθείσα γεωτεχνική ενότητα, προκειμένου να καθορισθούν οι χαρακτηριστικές τιμές όλων των παραμέτρων και να επιλεχθούν οι κατάλληλες παράμετροι σχεδιασμού για κάθε ενότητα. Τέλος, μετά την ολοκλήρωση της επεξεργασίας και αξιολόγησης όλων των διαθέσιμων στοιχείων, επισημάνθηκαν τα κρίσιμα σημεία που αναμένεται να αντιμετωπιστούν κατά τη φάση κατασκευής του έργου και διατυπώθηκαν προτάσεις – λύσεις για την ορθή και ασφαλή αντιμετώπισή τους.The subject of this dissertation is “Study of the geological – geotechnical conditions along the Line 4 route of Athens Metro, section Faros – Maroussi”. The scopes of this dissertation were to determine the geological – geotechnical model of the ground along the particular section of the new line route that is planned to be constructed shortly, to point out the crucial issues that may be faced and to propose solutions for the proper and safe construction of the project. The first step was to gather all the geotechnical research data available for the wider area of the project and the relevant bibliographical sources. After that, we proceeded with the presentation of the geological data and the evaluation of the geological conditions at the study area, that included the design of a geological map and a geological cross-section along the route, such as the determination of subsections with common geological characteristics. The next step of the present study was the digital recording and the management of all the data gathered in a unique geotechnical data base, concluding to the categorization of the geotechnical parameters of the geotechnical units met in the wider area. The data obtained were then inserted to a Geographical Information System (G.I.S.) in order to create digital maps for the visualization of important information related to the project. Additionally, we executed a statistical elaboration of the insitu and laboratory tests results, so as to determine the characteristic values of all the parameters and to choose the proper design parameters values for each geotechnical unit. At the end, the crucial issues that are expected to be found during the construction of the project and suggestions for the proper and safe solution of these issues were pointed out.Εμμανουήλ Γ. Βαρδαβάκη

Effects of ozone fumigation on cotton (Gossypium hirsutum L.) morphology, anatomy, physiology, yield and qualitative characteristics of fibers

This experiment was conducted to study the effect of high ozone concentrations on two cotton (Gossypium hirsutum L.) cultivars. Two cotton cultivars (Roma nos and Allegria) were exposed to con trol (CF < 4 ppb O(3)) and 100 ppb O(3). Plant expos ore to ozone began eight days after emergence and was interrupted one day before removing the leaves, to calculate the leaf area. Plants were exposed to ozone 7 h/day, in closed and controlled-environment chambers, during their illumination with artificial visible light. In comparison to control plants. plants exposed to O(3) showed chlorotic and necrotic patches on their leaves. increased stomatal or epidermal cell density and yellowness of cotton fibers. Elevated ozone concentration did not have a significant effect on stomatal width, total leaf thickness and thickness of histological components of leaves. Exposure to ozone concentration reduced non-glandular hair density of main leaf veins, plant height, mainstem internode length, chlorophyll content, net photosynthetic rate, stomatal conductance and length and area of bracts and petals. Elevated ozone treatment reduced the maximum length of staminal tube, anther number, pollen grain germination, leaf area, leaf dry weight, boll number, raw cotton weight, total branch length, dry weight of the mainstem-branches-bracts-carpophylls and of root dry weight. Furthermore, exposure to O(3) reduced the seed weight, the lint weight. the yield, the ratio of lint weight to seed weight, the fiber strength, the micronaire, the maturity index and the fiber uniformity index values. This study shows chat the exposure to high ozone concentrations mainly affected the rate of photosynthesis. raw cotton weight and strength of cotton fibers. (C) 2009 Elsevier B.V. All rights reserved

Seed Germination and Seedling Emergence of Shepherd's needle (Scandix pecten-veneris) as Affected by Seed Weight or Burial Depth

Shepherd's needle (Scandix pecten-veneris L.) is a very common broadleaf weed of winter cereals and also an edible weed used in many regions in Greece. Knowing the behavior of the weed seeds in the soil may help in designing its management strategy and its future cultivation. Field and laboratory experiments were conducted to evaluate the effect of seed weight or burial depth on seed germination and seedling emergence in 2008 and 2010. For seed weight effect on germination and seedling emergence light and heavy seeds were tested by Petri dish assay and in the field (sowing depth 4 cm). For burial depth study six depths - 2.5, 5, 7.5, 10, 12.5 and 15 cm - were examined in field trials made in two periods of time: 25 November and 15 March for two years. Percentage of seed germination, seedling emergence and mean emergence time were measured. Results showed that light seeds germinated better (74±2.2-95±2.2%) and earlier (20.5±0.64-31.0±0.45 days) than heavy seeds (34±3.2-58±5.1% and 25.4±0.57-33.8±0.46 days, respectively). The burial depth influenced seedling emergence and mean emergence time (MET) in most cases. Low emergence percentage (1.7±1.1-33.8±7.2%) was found at the depth of 15 cm and high at depth of 2.5, 5, 7.5 cm. Seeds sowed 15.0 cm deep had higher MET (27.0±0.9-55.1±1.1 days) than those sowed at 2.5 cm (20.9±0.9-41.6±0.5 days)

GROWTH OF WEED AND CROP PLANTS UNDER CADMIUM STRESS AND THEIR PHYTOREMEDIATION POTENTIAL

Phytoremediation is a promising new technology to remediate ecosystems using certain plants that can accumulate and withstand relatively high concentrations of a pollutant. Growth traits and cadmium (Cd) uptake of two weeds (Phalaris minor, Abutilon theophrasti) and four crop species (Gossypium hirsutum, Cichorium intibus, Vicia sativa, Apium graveolens) grown in soil with varying levels of Cd (0-200 mg/kg), were studied in a greenhouse under controlled environment for 5-7 weeks. The species tolerance to Cd (as plant growth), in descending order, was: V. sativa > Gossypium hirstitum >A. graveolens, C intibus, A. theophrasti >P. minor. Cadmium, accumulated mainly in roots, 50-76%, depending on species, (except for C. intibus), while the rest 24-50% was transferred to shoots the concentration being positively related to Cd level in soil. C. intibus with high accumulation and transfer factor (TF) of Cd (the ratio of shoot Cd concentration to the available Cd in soil) in shoots. A. graveolens with high Cd concentrations in roots, and V. sativa with the highest tolerance and biomass production seem to have a potential in phytoremediation to remove Cd from contaminated soils

Succession of microfungal communities on Myrtus communis leaf litter in a Sardinian Mediterranean maquis ecosystem

The succession of microfungal communities on Myrtus communis leaf litter was monitored from Jan. 1993 to Nov. 1994 using the litter bag method. Three main groups of fungal colonizers were identified, whose presence is correlated with the successive decomposition stages of the substrate and with seasonal variations.