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Dissertations / Theses on the topic 'In situ'

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Published: 4 June 2021
Last updated: 7 September 2024

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1

Leadley, Marcus. "In situ listening : soundscape, site and transphonia." Thesis, Goldsmiths College (University of London), 2015. http://research.gold.ac.uk/15066/.

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This enquiry represents an exploration of environmental sound and artistic practice from the perspectives of in situ listening and transphonia. The initial term, in situ listening, has been coined by the author in order to constellate a group of intellectual trajectories and artists’ practices that engage with recorded sound and share a common theme: that the listening context, the relationship between mediated sound and site, is an integral part of the engagement process. Heikki Uimonen (2005, p.63) defines transphonia as the, “mechanical, electroacoustical or digital recording, reproduction and relocating of sounds.” The term applies to sound that is relocated from one location to another, or sound that is recorded at a site and then mixed with the sound of the prevailing environment. The experience of the latter, which is a key concern for this thesis, may be encountered during the field recording process when one ‘listens back’ to recordings while on site or during the presentation of site-specific sound art work. Twelve sound installations, each based on field recordings, were produced in order to progress the investigation. Installations were created using a personally devised approach that was rigorous, informed, and iterative. Each installation explored a different environment. These installations, and their related environmental studies, form the core content of this enquiry. In the first part of this thesis the installations are used to explore observations of transphonic audio content in relation to a number of subjective, surprising and intangible phenomena: disorientation, uncanny sensations or even the awareness of coincidence. These observations are supported and contextualised in relation to a wide range of historic and contemporary sources. Works in the second part of the thesis are used to motivate a meditation on the relationship between soundscape, site and time, which was proposed by the initial phase of the research.
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2

Dutil, Daniel. "L'in situ trans-site, selon une perspective de l'interactionnisme symbolique." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1994. http://theses.uqac.ca.

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Mémoire (M.A.)-- Université du Québec à Chicoutimi, 1994.
Cette communication a été réalisée à l'Université du Québec à Chicoutimi dans le cadre du programme de maîtrise en arts plastiques de l'Université du Québec à Montréal extensionné à l'Université du Québec à Chicoutimi. CaQCU Document électronique également accessible en format PDF. CaQCU
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3

COSTANZO, ERIKA. "Site Assessment and in Situ Maintenance of a Wind Farm." Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263198.

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Gli effetti dell’orografia di uno specifico sito sul flusso di vento incidente su una turbina eolica possono essere analizzati attraverso due metodologie: misure dirette in sito o test sperimentali in galleria del vento su modelli in scala. La prima opzione ha come vantaggio l’individuazione delle reali condizioni di flusso che si sviluppano in una data area, a prezzo però di tempi di esecuzione delle prove non indifferenti e limitato numero di punti che si possono indagare a causa degli elevati costi associati all’acquisto delle attrezzature richieste. La seconda opzione consente sicuramente una notevole riduzione dei tempi e dei costi, ma le approssimazioni che necessariamente occorre fare possono condurre a risultati pesantemente distanti dalla realtà. In questo lavoro è stato affrontato il primo dei due metodi esposti attraverso la certificazione di una turbina eolica direttamente in orografia complessa. Poiché il caso di studio è protetto da segreto industriale, il contributo della scrivente è stato, in particolare, la definizione delle procedure necessarie a caratterizzare gli effetti del sito sul flusso incidente mediante prove dirette, un commento critico a quanto è stato affrontato ed un’analisi delle normative di riferimento durante lo svolgimento dei lavori. Parallelamente alla certificazione della turbina è emerso quanto siano difficoltose le operazioni di ispezione della macchina, specie in orografia complessa. Tipicamente avvengono tramite l’arrampicata su fune di un operatore, ma in situazioni in cui i venti sono più forti e le condizioni climatiche possono cambiare velocemente, queste operazioni sono tutt’altro che banali. Il gruppo di ricerca di cui la scrivente è stata parte, ha quindi deciso di intraprendere la messa appunto di un sistema basato sull’utilizzo di un mezzo aereo a pilotaggio remoto il cui scopo fosse quello di consentire ispezioni visive e nell’infrarosso dello stato di manutenzione delle turbine eoliche.
The effects of the orography on the wind flow incident on a wind turbine can be analyzed through two methodologies: direct measurements on site or experimental tests in wind tunnel on scale models. The first option advantage is the identification of the real flow conditions that develop in a given area, but test times are often too long and a limited number of points can be investigated due to the high costs of the required equipment. The second option certainly allows a considerable reduction in time and costs, but the approximations that necessarily need to be done can lead to results that are far from reality. In this paper the first of the two methods presented was examined through the certification of a wind turbine directly in complex orography. Since the test case is protected by industrial secrecy, the writer's contribution was, in particular, the analysis of the procedures to characterize the effect of the site on the incident flow by means of direct tests, a critical comment and an analysis of the reference regulations during the course of the works. Parallel to the certification of the turbine, it emerged how difficult the inspection operations of the machine are, especially in complex orography. Typically, they happen by means of an operator climbing a rope, but in situations where the winds are stronger and the climatic conditions can change quickly, these operations are anything but trivial. The research group of which the writer was a part, has therefore decided to engine a system based on a drone to allow visual and infrared inspections of the state of maintenance of wind turbines.
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4

Klose, Martin C. "Fermentation mit In-situ-Extraktion und In-situ-Elektroextraktion." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962119555.

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5

Thorgrimsson, Bjarni S. H. "Oseberg in situ." Thesis, Norges teknisk-naturvitenskapelige universitet, Fakultet for arkitektur og billedkunst, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-17622.

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6

Lindberg, My, and Frida Lindstrii. "PVK IN SITU." Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26113.

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Lindberg M & Lindstrii F. PVK in situ. En observationsstudie av följsamhet tillriktlinjer gällande skötsel, dokumentation vid fixeringsförband,komplikationssymptom samt tid in situ. Examensarbete i omvårdnad 15högskolepoäng. Malmö högskola: Fakulteten för hälsa och samhälle, institutionenför vårdvetenskap, 2014.Bakgrund: perifer ven kateter (PVK) är ett mycket vanligt ingrepp inomsjukvården som medför risker för kateterrelaterade komplikationer. I Sverige ärdet främst sjuksköterskans uppgift att hantera vården kring PVK. Vårdhandbokenhar som uppgift att säkerhetsställa en god säker vård genom att publiceralättillgängliga riktlinjer för olika moment inom sjukvården. Genom att följavårdhandbokens riktlinjer avseende PVK kan riskerna för komplikationer minska.Syfte: beskriva följsamhet till vårdhandbokens riktlinjer gällande skötsel av PVK,dokumentation vid fixeringsförband, byte vid komplikationssymptom samt attbeskriva tid in situ av PVK på vårdavdelningar.Metod: en observationsstudie genomfördes på ett större och ett mindre sjukhusi södra Sverige. Datainsamling gjordes under två veckors tid med hjälp av ettvaliderat och reabilitetstestat instrument, PVC – Assess, och ett eget framtagetprotokoll av författarna. Totalt insamlades 64 PVK observationer.Resultat: följsamheten till vårdhandbokens riktlinjer var inte tillfredsställande vidmajoriteten av variablerna i PVC-Assess, dokumentation vid fixeringsförbandetoch tid in situ.Slutsats: studien har metodologiska brister som medför att resultatets trovärdighetblir låg. Dock antyder resultatet på att det finns brister i följsamheter kringriktlinjer avseende PVK.
Lindberg M & Lindstrii F. PVC in situ. An observational study of adherence towards guidelines regarding the management, documentation at fixationdressings, symptoms of complications and the time in situ. Degree project in nursing 15 credit points. Malmö University: Faculty of health and society, Department of care science, 2014.Background: peripheral vein catheter (PVC) is a very common procedure in healthcare that involves risks for catheter-related complications. In Sweden, the management and care of PVC is primary performed by nurses. The handbook for healthcare’s task is to provide a good and safe care by publishing accessible guidelines on various topics in healthcare. By following the handbook for healthcare’s guidelines regarding PVC the risks for complications can be reduced. Aim: describe adherence to the handbook for healthcare’s guidelines regarding the management of PVC, documentation at fixation-dressings, changing by complication-symptoms and to describe time in situ of PVC in wards.Method: an observational study was conducted on a larger and a smaller hospital in southern Sweden. Data collection was done in two weeks’ time with the help of a validated and reliability-tested instrument, PVC - Assess, and a protocol developed by the authors. Total of 64 PVC were observed.Results: adherence to the handbook for healthcare’s guidelines were not being guaranteed by the majority of the variables in PVC-Assess, documentation at fixation dressing and the time in situ.Conclusion: the study has methodological shortcomings that lowers the results credibility. However, the results suggests that there is still a lack of compliance regarding PVC-guidelines.
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7

Lange, Sven. "In-Situ-Sortierverfahren." [S.l.] : Universität Stuttgart , Fakultät Informatik, 1997. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB6783502.

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8

MATHEY, ANNICK. "De in situ lichenum investigatione de l'analyse in situ des lichens." Paris 6, 1987. http://www.theses.fr/1987PA066744.

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Le but de l'etude est de montrer, a partir d'exemples qu'il est possible de reunir des informations sur une plante (morphologie, anatomie, chimie et ecologie) sans creation d'artefact et de remplacer des donnees subjectives par des donnees mesurables, c'est-a-dire reproductibles. Les lichens constituent un modele biologique
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9

Jumper, Natalie. "Application of a site-specific in situ approach to keloid disease research." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/application-of-a-sitespecific-in-situ-approach-to-keloid-disease-research(f0a9bcae-93f0-4335-8839-afa5747f40d6).html.

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Keloid disease (KD) is a cutaneous fibroproliferative tumour characterised by heterogeneity, locally aggressive invasion and therapeutic resistance. Clinical, histological and molecular differences between the keloid scar centre and margin as well as recent evidence of the importance of epithelial-mesenchymal interactions (EMI) in KD pathobiology contribute to the complexity and diversity of KD, which coupled with the lack of a validated animal model have hindered research and effective management. Despite significant progress in the field of KD research, reliance on conventional monolayer cell culture and whole tissue analysis methods have failed to fully reflect the natural architecture, pathology and complexity of KD in vivo. In order to address these challenges, a site-specific in situ approach was therefore employed here for the first time in KD research. The first aim of this work was to compare the value of this contemporary approach with traditional methods of tissue dissection. The second aim was to compare the genomic expression between well-defined, distinct keloid sites and normal skin (NS). The third aim was to develop and explore hypotheses arising from this site-specific gene expression profiling approach, so as to enhance understanding of KD pathobiology as a basis for improved diagnostic and therapeutic strategies in future KD management. The fourth aim was to probe these hypotheses with relevant functional in vitro studies. The current site-specific in situ approach was achieved through a combination of laser capture microdissection and whole genome microarray, allowing separation of epidermis from dermis for keloid centre, margin and extralesional sites compared with NS. This in situ approach yielded selective, accurate and sensitive data, exposing genes that were overlooked with alternative methods of dissection. Identification of significant upregulation of the aldo-keto reductase enzyme AKR1B10 in all three sites of the keloid epidermis (KE) in situ, implicated dysregulation of the retinoic acid (RA) pathway in KD pathogenesis. This hypothesis was supported by showing that induced AKR1B10 overexpression in NS keratinocytes reproduced the keloid RA pathway expression pattern. Moreover, co-transfection with a luciferase reporter plasmid revealed reduced RA response element activity. Paracrine signals released by AKR1B10-overexpressing keratinocytes into conditioned medium resulted in TGFβ1 and collagen upregulation in keloid fibroblasts, suggesting the disturbed RA metabolism exerts a pro-fibrotic effect through pathological EMI, thus further supporting the hypothesis of RA deficiency in KE. Gene expression profiling further revealed an upregulation of NRG1 and ErbB2 in keloid margin dermis. Exogenous NRG1 led to enhanced keloid fibroblast migration with increased Src and PTK2 expression, which were attenuated with ErbB2 siRNA studies. Together with the observed failure to recover this expression with NRG1 treatment, suggested the novel KD pathobiology hypothesis that NRG1/ErbB2/Src/PTK2 signaling plays a role in migration at the keloid margin. In addition to these hypotheses, LCM methodology with comprehensive analysis of the data permitted the development of additional novel working hypotheses that will inform future KD research, including inflammatory gene dysregulation and cancer-like stem cells that may contribute to the therapeutic resistance characteristic of KD.
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10

Panza, Fabien. "Développement de la spectrométrie gamma in situ pour la cartographie de site." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00975929.

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La spectrométrie gamma à haute résolution offre un outil d'analyse performant pour effectuer des mesurages environnementaux. Dans le cadre de la caractérisation radiologique d'un site (naturelle ou artificielle) ainsi que pour le démantèlement d'installations nucléaires, la cartographie des radionucléides est un atout important. Le principe consiste à déplacer un spectromètre HPGe sur le site à étudier et, à partir des données nucléaires et de positionnements, d'identifier, de localiser et de quantifier les radionucléides présents dans le sol. Le développement de cet outil fait suite à une intercomparaison où un exercice orienté intervention a montré les limites des outils actuels. Une partie de ce travail s'est portée sur la représentation cartographique des données nucléaires. La connaissance des paramètres d'un spectre in situ a permis la création d'un simulateur modélisant la réponse d'un spectromètre se déplaçant au-dessus d'un sol contaminé. Ce simulateur a lui-même permis de développer les algorithmes de cartographie et de les tester dans des situations extrêmes et non réalisables. Ainsi, ce travail ouvre sur la réalisation d'un prototype viable donnant en temps réel les informations nécessaires sur l'identité et la position possible des radionucléides. La recherche réalisée sur la déconvolution des données permet de rendre en post traitement une carte de l'activité du sol par radionucléide mais également une indication sur la profondeur de la source. Le prototype nommé OSCAR (Outil Spectrométrique de Cartographie de Radionucléides) a ainsi été testé sur des sites contaminés (Suisse et Japon) et les résultats obtenus sont en accord avec des mesures de référence.
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11

Panza, Fabien. "Développement de la spectrométrie gamma in situ pour la cartographie de site." Electronic Thesis or Diss., Strasbourg, 2012. http://www.theses.fr/2012STRAE043.

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La spectrométrie gamma à haute résolution offre un outil d’analyse performant pour effectuer des mesurages environnementaux. Dans le cadre de la caractérisation radiologique d’un site (naturelle ou artificielle) ainsi que pour le démantèlement d’installations nucléaires, la cartographie des radionucléides est un atout important. Le principe consiste à déplacer un spectromètre HPGe sur le site à étudier et, à partir des données nucléaires et de positionnements, d’identifier, de localiser et de quantifier les radionucléides présents dans le sol. Le développement de cet outil fait suite à une intercomparaison où un exercice orienté intervention a montré les limites des outils actuels. Une partie de ce travail s’est portée sur la représentation cartographique des données nucléaires. La connaissance des paramètres d’un spectre in situ a permis la création d’un simulateur modélisant la réponse d’un spectromètre se déplaçant au-dessus d’un sol contaminé. Ce simulateur a lui-même permis de développer les algorithmes de cartographie et de les tester dans des situations extrêmes et non réalisables. Ainsi, ce travail ouvre sur la réalisation d’un prototype viable donnant en temps réel les informations nécessaires sur l’identité et la position possible des radionucléides. La recherche réalisée sur la déconvolution des données permet de rendre en post traitement une carte de l’activité du sol par radionucléide mais également une indication sur la profondeur de la source. Le prototype nommé OSCAR (Outil Spectrométrique de Cartographie de Radionucléides) a ainsi été testé sur des sites contaminés (Suisse et Japon) et les résultats obtenus sont en accord avec des mesures de référence
The high-resolution gamma spectrometry currently provides a powerful analytical tool for performing environmental measurements. In the context of radiological characterization of a site (natural or artificial radioactivity) and for the dismantling of nuclear installations, mapping of radionuclides is an important asset. The idea is to move a HPGe spectrometer to study the site and from nuclear and position data, to identify, to locate and to quantify the radionuclides present in the soil. The development of this tool follows an intercomparaison (ISIS 2007) where an intervention / crisis exercise showed the limits of current tools. The main part of this research project has focused on mapping of nuclear data. Knowledge of the parameters of an in situ spectrum helped to create a simulator modeling the response of a spectrometer moving over contaminated soil. The simulator itself helped to develop algorithms for mapping and to test them in extreme situations and not realizable. A large part of this research leads to the creation of a viable prototype providing real-time information concerning the identity and locality as possible radionuclides. The work performed on the deconvolution of data can make in post processing a map of the activity of radionuclide soil but also an indication of the depth distribution of the source. The prototype named OSCAR was tested on contaminated sites (Switzerland and Japan) and the results are in agreement with reference measurements
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12

Weigert, Erich. "An ex-situ and in-situ evaluation of carbides as potential electrocatalysts." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 156 p, 2008. http://proquest.umi.com/pqdweb?did=1456296211&sid=11&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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13

Waller, A. M. "In-situ electrochemical E.S.R." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233517.

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14

Chan, Paul Wing Hung. "In-situ viscosity measurement." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341507.

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15

Temple-West, Frances P. "A House In Situ." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50520.

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The project is located in the Teton Valley of Idaho, sited on the eastern slope of the Big Hole Mountains oriented toward the western face of the Teton Mountain Range. The program is a vacation house for a young family of four to be used throughout the year. Themes covered in the project include issues of topography, site conditions, and landscape; the harnessing of a powerful context and views; water management specific to the site; architectural expressive form and scale; circulation; and materiality. The site and its conditions, including slope, vegetation, sun orientation, wind direction, drainage patterns, and views, were the driving forces behind most of the design decisions made for the project. Circulation on and off the site, how one moves throughout the house, location of the program elements, placement and size of windows to capture views, and material selection were all inextricably tied to the physical nature of the site and its environment. The project is documented with diagrams, line drawings, perspective renderings and model photographs to illustrate the thesis.
Master of Architecture
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16

Bukvišová, Kristýna. "In-situ elektronová mikroskopie." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402571.

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Cílem diplomové práce je popsat oxidaci nanotrubic sulfidu wolframičitého za zvýšených teplot v přítomnosti vodní páry. Na jejich povrchu se nejprve vytvoří nanočástice oxidu wolframu, ze kterých potom vyrůstají nanodráty. Na základě in-situ experimentů v rastrovacím elektronovém mikroskopu je navržen mechanismus reakce a ten je zjednodušeně popsán analyticky. Ukazuje se, že elektronový svazek má zásadní vliv na reakci.
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17

Martis, M. "In situ and ex situ characterization studies of transition metal containing nanoporous catalysts." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1334587/.

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The research within this thesis has concentrated around characterization of nanoporous catalysts with metals incorporated or substituted inside the framework, and inside the cavities as small clusters, and in very low concentrations. The main objective has been to advance the understanding of the structure and active sites, and relate them to their catalytic properties through the use of combination in situ and ex situ methods and in some cases combination with optical spectroscopic techniques. Characterisation methods include synchrotron radiation based techniques, high-resolution powder diffraction (HRPD) and X-ray absorption spectroscopy (XAS), and laboratory based X-Ray Diffraction (XRD), Infrared Spectroscopy (IR), Raman Spectroscopy (RS), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy TEM A combination of techniques is used to investigate cobalt substituted AlPO-18 prepared by different compositions. The determination of the nature of cobalt ions, in particular their location in the samples was carried by XAS. Additionally, a new in situ IR cell was developed which allowed to determine the nature of the redox chemistry of cobalt ions in the samples. Structural changes during calcinations and methanol to olefins reaction (MTO) were studied on transition metals substituted (Co, Zn, Si) small pore AlPO-18. Using diffraction methods it was possible to accurately determine the changes in the lattice parameters and correlate this with metal ion incorporation into the lattice, and also determine the negative thermal properties of these materials prior to catalytic reactions; the study also allowed us to follow their stability during calcination. High energy X-ray diffraction (HEXRD PDF method) measurements gave an insight into the direction of possible lattice contraction during calcination which may be related to shape-selective catalytic properties of these solids. Characterization of a series of vanadium containing ZSM-5 was carried by in situ XAS and Raman spectroscopy. The catalytic activity was very different, and detailed understanding of the vanadium environment using XAS and Raman spectroscopy provided an insight into the nature of vanadium ions in the zeolites. In the last part of the thesis, a series of platinum impregnated zeolite beta and ferrierite were characterized to understand how the nano clustered platinum metal particles (active centres) were created during activation, and the study also allowed us to estimate the size and sitting of the platinum cluster inside the zeolite lattice.
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18

Henshaw, Sarah-Louise. "NMR studies of ruthenium and rhodium complexes : in-situ and ex-situ photochemistry." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/17209/.

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Catalytic processes often involve organometallic complexes, the aims of this thesis were to study some specific ruthenium and rhodium complexes using photochemistry. This allowed their behaviour towards small molecules to be investigated since the coordination and activation of small molecules are fundamental parts of catalytic cycles. A further aim was to study suitable complexs with parahydrogen using time-resolved NMR methods with the intention of measuring p-H2 addition and/or the evolution of the p-H2-derived singlet state The photochemistry of CpRh(CH2CHSiMe3)2 (2.1), CpRh(COE)2 (2.2) and CpRh(COD) (2.3) with DMSO PhSOMe, trimethylvinylsilane and triethylsilane was probed. The photoactivity of 2.3 proved minimal with the main products being associated with the loss of the COD ligand. By contrast, 2.1 and 2.2 undergo the substitution of one or both of the alkene ligands, depending on the nature of the reacting ligand. Complexes 2.1, CpRh(CH2CHSiMe3)(DMSO) (2.4) and CpRh(P*Ph)(C2H4) (3.2) were deemed suitable for time-resolved studies with p-H2. 2.1 was found to form the expected dihydride (3.1) on a 50 ms timescale. 2.4 was also formed 3.1 but its PHIP enhancement was poor and whilst 3.1 did form the expected dihydride product PHIP was not observed. [Ru(H)2(CO)(PPh3)(Xantphos)] 5.1 was also synthesised and its reactivity towards a range of small molecules, which included DMSO, CO, ethene and Et3SiH, investigated. These studies revealed that its H2, CO and PPh3 ligands could all be lost photochemically and that the xantphos ligand could switch between κ2-PP and κ3-POP coordination. Time-resolved NMR studies on 5.1, with p-H2, found the H2 addition to the intermediate to occur with a rate of the order of 0.5 s−1. cis-[Ru(H)2(dppp)2] 6.1 was also studied using time-resolved NMR, in this case the rate of H2 addition was faster than the NMR timescales. This allowed the evolution of the p-H2 singlet state to be probed and shown to be as a function of the difference in scalar coupling between the hydrides and the equatorial 31P nuclei.
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RAVAZZINI, CLAUDIO. "Barriere idrauliche e fisiche nei siti contaminati. Prove in situ e modellazione numerica." Doctoral thesis, Università Politecnica delle Marche, 2014. http://hdl.handle.net/11566/242839.

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La presente tesi tratta il tema del barrieramento idraulico-fisico dei siti inquinati. Dopo una prima parte di introduzione alle problematiche ambientali dei siti ad alto tasso di inquinamento (SIN-Siti Interesse Nazionale), vengono riportati la teoria e lo stato dell’arte alla base delle barriere idrauliche e delle barriere fisiche. Nello specifico, la trattazione di questi argomenti è stata rivolta all’applicazione di questa tecnologia in due SIN, siti contaminati dalla presenza di attività legate alla trasformazione di prodotti petroliferi. I siti in esame sono tutt’ora in esercizio e sono ubicati lungo la linea di costa marittima delle due maggiori isole italiane (per una richiesta di privacy da parte della committenza, non saranno forniti ulteriori dettagli circa la loro ubicazione esatta). Nel primo caso verrà presentato lo studio riguardante un’area già interessata da un barrieramento idraulico pre-esistente, barrieramento per il quale si prevede la realizzazione di ulteriori pozzi oltre alla realizzazione di un diaframma plastico composito. Entrambi i progetti di integrazione del sistema di barrieramento del sito sono stati richiesti dal MATTM. Lo studio, costituito da prove in situ/laboratorio e da modellazione numerica attraverso software di calcolo dedicati, si è concentrato in questo primo caso sulla equivalenza in termini prestazionali del barrieramento idraulico accoppiato ad un barrieramento fisico realizzato in jet-grouting (progetto di variante) piuttosto che attraverso un diaframma plastico composito (progetto originario). Il modello numerico è stato costituito a partire dal modello generale già esistente per l’area, focalizzando lo studio in particolare sulla zona denominata area ribassata. Questa area risulta di particolare interesse in quanto presenta particolari condizioni stratigrafiche ed idrauliche essendo essa situata su di un paleo-alveo. Proprio questa sua natura rappresenta un fattore di maggiore rischio sia nel caso di malfunzionamento della barriera idraulica (trasporto dei contaminanti più veloce), sia per il caso di intrusione del cuneo salino (ingresso più veloce dei cloruri). Proprio per questo fine è stato anche creato un ulteriore modello di calcolo che tenesse in conto dei flussi densità dipendenti, per poter verificare l’andamento del cuneo salino nel tempo, sia in presenza delle due barriere fisiche sia in assenza di esse. Nel secondo caso verranno invece presentatati i risultati dello studio riguardante l’efficienza di un barrieramento idraulico esistente. Anche in questo caso il Ministero per l’Ambiente (MATTM), al fine di garantire la messa in sicurezza del sito ha avanzato la richiesta di un barrieramento fisico fino ad una profondità di ca. -130 m s.l.m.. L'approfondimento proposto nella presente tesi, attraverso l'interpretazione delle prove in situ/laboratorio eseguite e la realizzazione di una modellazione numerica dell'intera area a livello di stabilimento, vuole avere lo scopo di verificare il grado di efficienza attuale del barrieramento idraulico in opera, per poter valutare l'ipotesi di evitare la costruzione del barrieramento fisico futuro (modifica art 243 D.Lgs 152/2006).
This thesis deals with the topic of physical-hydraulic barriers for polluted sites. After a first part of introduction to the environmental problems of the sites with high levels of pollution (SIN-Sites of National Interest), theory and state of the art at the base of the hydraulic barriers and physical barriers are reported. Specifically, these topics has been used to the application of this technology in two SIN, contaminated by the presence of activities related to the processing of petroleum products. The two sites are still in operation and are located along the seacoast of the two largest islands in Italy (for a privacy request by the client, will not be provided more details about their exact location). In the first case, study will be presented on an area with the presence of a pre- existing hydraulic barrier. In this site it is projected the construction of additional wells and the construction of a composite plastic diaphragm. Both projects of system integration barriers of the site were required by the MATTM (Mynistry of Environment). The study, consisting of in situ tests / laboratory and numerical modeling through calculation software dedicated, focused in this case on equivalence in terms of performance of an hydraulic barrier coupled to a physical barrier made of jet-grouting (new project) rather than made of a composite plastic diaphragm (original project) . The numerical model was formed from the existing general numerical model of the area, focusing in particular on the study area called “low area”. This area is of particular interest as it presents particular stratigraphic and hydraulic conditions since it is situated on a soil with high conductivity. The high conductivity is a natural factor of increased risk both in case of malfunction of the hydraulic barrier (faster transport of contaminants), both in case of intrusion of salt wedge (quicker entry of chlorides) . For this purpose has been also created an additional calculation model that is able to consider density dependent flows, in order to verify the position of the salt wedge during time, both in the presence of the two physical barriers both in the absence of them. In the second case the results of the study on the efficiency of an existing hydraulic barrier will be presented. Also in this case the Ministry for the Environment (MATTM), in order to ensure the safety of the site has made the request of a physical barrier up to a depth of approx. -130 m s.l.m.. The study proposed in this second case, through the interpretation of in situ tests / laboratory tests and the development of a numerical modeling of the entire area, has the aim to verify the efficiency of the working hydraulic barrier in order to avoid the construction in the near future of the requested physical barrier (art 243 D.Lgs 152/2006).
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20

Sutherland, Margaret Lloy. "Molecular and ontogenic analysis of the mammalian GABA_A receptor." Thesis, Open University, 1998. http://oro.open.ac.uk/54847/.

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γ-aminobutyric acid is the major inhibitory neurotransmitter in the adult mammalian central nervous system (CNS) and may also play a neurotrophic role during CNS development. Diversification of GABAA receptor mediated responses are in part a result ofvariation in subunit composition in the receptor complex. This variation arises both from the number of different subtypes of GABAA receptor subunits (α1-6, β1-4, γ1-3, δ1, ρ1-3, ε, ρ), as well as from post-transcriptional processes such as RNA splicing. In this thesis, I have investigated the developmental onset of GABAA receptor gene expression and the distribution and temporal expression of GABAA receptor subunit mRNAs and 12 splice variants within the developing and adult murine CNS. Preliminary studies using S 1 nuclease protection analysis demonstrated that α1, β3 and γ2 were the predominant subtypes of GABAA receptor subunits expressed at embryonic day 14 and in the adult murine CNS. In situ hybridisation analysis demonstrated overlapping but distinct spatial and temporal patterns of GABAA subunit mRNA expression during postnatal development and in the adult murine CNS. Analysis of γ2 mRNA splice variants demonstrated that the γ2S transcript is the predominant γ2 mRNA expressed during latter stages of embryo genesis, while the γ2L transcript is the predominant γ2 isoform present inthe adult CNS. Since there is a 29 to 47 percent amino acid identity among the various GABAA receptor subunits, I have also demonstrated through site-directed mutagenesis studies, that changes in a conserved amino acid in the cysteine loop of the bovine a 1 GABAA receptor subunit resulted in a loss of agonist and antagonist binding (DI49N), while a change in a conserved amino acid in the M1 transmembrane domain of the bovine α1 GABAA receptor subunit resulted in loss of agonist binding and reduction in the Bmax and Kd for antagonist binding (P243A). 'These results are in contrast to the effect of identical mutations in the bovine β1 subunit and suggest that if the pentameric GABAA receptor assembly is composed of (α1)2(β1)1(γ2)2, then changes in highly conserved amino acids in the α1 receptor subunit would have a greater distortion on the structure of the receptor complex.
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Wittge, Jochen [Verfasser], and Arne [Akademischer Betreuer] Cröll. "In situ investigation of defects in semiconductors = In Situ Erforschung von Defekten in Halbleitern." Freiburg : Universität, 2011. http://d-nb.info/1122592213/34.

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Guimaraes, de Sa Rafael. "In-situ and ex-situ incorporation of carbon nanostructures into ceramic-carbon-metal nanocomposites." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526358.

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Kunde, Miriam Nora. "Ex-situ and In-situ Conservation Approach for the Malayan Sun Bear (Helarctos malayanus)." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/373043.

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Habitat loss and fragmentation, the illegal wildlife trade and exploitation for Traditional Chinese Medicine (TCM) threaten the sun bear (Helarctos malayanus) with extinction. The confiscation or rescue of bears affected by each of these threats results in an ethical dilemma for conservation practitioners as they must decide over the fate of the confiscated bear and which decision is in the interest of long-term species survival. To understand the conservation status of any species, it is essential to have access to as much long-term information as possible. This requires a standardized approach to communicate research results and approaches in order to inform scientists without the risk of data being miss-interpreted. Using the standardized PRISMA-p model (commonly applied in medical professions) in the systematic review of white literature on sun bears (Chapter 2) resulted in the Helarctos-database that will be made publicly available. This method allowed for a standardized reporting on the current literature and revealed that the sun bear has been neglected by the scientific community. Furthermore, it identified genetic (and genomic) research on the sun bear as one of the main research gaps. Genetics and genomics find many applications in ex-situ and in-situ conservation. To protect species, it is essential to understand their evolutionary history and adaptation potential to a changing environment. In Chapter 3 of this thesis, the mitochondrial genomes of museum-derived, as well as contemporary, sun bear samples covering most of the distribution range of the sun bear were sequenced using next-generation sequencing methods. While phylogeography helps to resolve taxonomic uncertainties, identify species and sub-species that may be warranted conservation priority, it also allows the identification of geographical barriers that may have led to speciation events. This first phylogeographic study of the sun bear revealed that there are two lineages: the ‘mainland’ lineage and the ‘sunda’ lineage. These lineages were disconnected at the Isthmus of Kra (Thailand), due to seawater level rises during the Pleistocene. This study demonstrated that waterbodies, if large enough, can create a geographical barrier for sun bears. Understanding barriers to gene-flow is essential for the effective protection of a species. As the human landscape alteration is causing the fragmentation of habitats, understanding the population structure, gene-flow between populations and their genetic variability is becoming essential for conservation management. Chapter 4 of this thesis demonstrates for sun bears in Cambodia how microsatellite (nuclear) markers can identify the number of populations and how these populations are connected. Microsatellite markers are a useful tool to identify hybridization and inbreeding in populations and are therefore capable of identifying populations of conservation concern. This research revealed that there are two sun bear populations, East and West of the Mekong river in Cambodia, and that these two populations are exchanging genes (as is an admixed population). In the population in West Cambodia, inbreeding was detected, indicating that the current exchange of genes between the two populations is not sufficient to maintain genetic diversity in the West population. Currently it is not known what may have caused the loss of genetic diversity of the Western population but illegal wildlife trade may be implicated. Microsatellite markers could be used to develop forensic markers to combat the illegal wildlife trade and to identify endangered animals in TCM products. Although the sun bear is used in TCM products, it is not understood to what level the TCM industry is threatening the sun bear. The fifth Chapter of the thesis tested forensic DNA extraction protocols, extraction kits and Gas-Chromatography Mass Spectrometry (GC-MS) on different Traditional Chinese Medicine products, to determine whether these samples contain sun bear derivate. Currently there are many forensic methods with reference databases for the Asiatic black bear but none regarding the sun bear. The forensic genetic methods employed here were not successful in heavily processed TCM products as they likely did not appear to contain any intact DNA. Therefore, the further development of genetic and non-genetic forensic method to detect sun bear is required. The final Chapter discusses how the findings of the previous Chapters can inform sun bear conservation practitioners who must decide whether they release a sun bear or whether they maintain it in captivity and advises on direct conservation action. Releasing a bear requires detailed knowledge and access to this knowledge about the species. The Helarctos-database would provide a one-stop for sun bear research. The phylogeography analysis identified that two genetically distinct lineages of sun bears. Although the study did not obtain enough samples to conclude on species and subspecies classification, understanding that the sun bears on the mainland are different to the sun bears on the Sunda islands is important for ex-situ breeding and release efforts. The microsatellite study demonstrated that nuclear markers can identify population hybridization, geographical barrier and inbreeding. In the West Cambodian sun bear population inbreeding was detected. This informs conservation actions such as potential augmentation, establishment of connectivity and further research. This study also successfully assigned sun bears of unknown origin to a potential source population, which is critical information for release projects. Furthermore, the forensic analysis of TCM products of sun bears highlighted that forensic methods currently available are ineffective on heavily processed TCM samples and need to be further developed. Being able to test whether sun bear derivate is present in TCM products is necessary to judge the level of threat imposed by the TCM industry on the Malayan sun bear.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Zhang, Ji. "STUDY OF BIOGASIFICATION OF COAL TO METHANE FOR EX SITU AND IN SITU APPLICATIONS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/dissertations/1476.

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Burning coal to generating electricity is certainly not environmentally friendly and sustainable. But considering its abundant and inexpensive nature, coal is not going to be completely replaced by other forms of fuels or disappear from the energy market in a short while. Thus, better and clean technologies, rather than combustion, need to be developed to utilize coal for generating valuables for the society. Specific for this study, coal bioconversion was investigated for the purpose of producing methane from coal. The first part of the dissertation characterized microbial communities dedicated for conversion of coal to methane in situ and ex situ. To enhance methane production in situ in bituminous coal seams, distribution of microorganisms in the formation water collected from a coalbed methane well (CBM) was investigated. Based on next generation 16S rDNA sequencing, both Bacteria (231species) and Archaea (33 species) were identified. Among the bacterial domain, polymer-degrading, benzoate, fatty acid and sugar utilizing bacteria were dominant. Among the archaea domain, the major methanogens (89.8%) belonged to the order of Methanobacteriales that are hydrogenotrophic. To develop a microbial consortium for ex situ coal bioconversion, the original microbial community was adapted to ground coals for five months in a laboratory environment. DNA sequencing revealed the presence of 185 bacteria species and nine archaea species that were dramatically different from those in the original formation water. In particular, the majority (90.4%) of methanogens were within the order of Methanomicrobiales. To increase methane production, two nutrient solutions were tested. Solution #2 which targeted methanogens provided a methane yield of 111 ft3/ton in 20 days, which translated to a 5.6 ft3/ton-day. In addition, the adapted consortium was found to be aerotolerant. The second part of the dissertation presented a suitable recipe for biogasifying coal collected from the Illinois basin. This recipe was developed based on formation water from local CBM well. To develop this recipe, the formation water’s chemical composition was analyzed first. This analysis revealed that the formation water had a distinct geochemical signature including a low concentration of sulfate, nitrate, calcium, and magnesium, but a high concentration of sodium, potassium, and chloride. To maximize methane yield from coal, a Box-Behnken design necessitating 29 reactors was adopted to find the optimal nutrient conditions. The optimal condition provided by the Design of Expert (DOE) software was: Fe powder at 74 mM, methanol at 97.9 mM, ethanol at 100 mM, and trace mineral supplement solution at 100%. Under these conditions, the predicated methane yield and content was 1,417.35 ft3/ton and 80.7%, respectively. To confirm these results, a verification experiment was conducted, where a methane yield of 1,390.22 ft3/ton with a methane content of 84.6% were observed, which were fairly close to the predicted values. In the last part of the dissertation, a 3-liter fermentor was established to evaluate Illinois coal biogasification in a larger reactor over a longer duration compared to those reported in the literature. During the one-year study, the developed recipe was added three times to sustain methane release from coal powders. After the fermentation was terminated, the residual coal and fermentation broth were characterized in detail. The cumulated methane production was 5,171 ft3/ton with a methane content of 75.36%. Compared to the untreated coal, the coal residue appeared to be finer and highly degraded with less carbon but more sulfur and ash. Based on mass balance, volatile and fixed carbon decreased 15.9% and 29.6%, respectively, using the untreated coal as the baseline. According to GC/MS analysis, the fermentation broth contained mainly three groups of compounds: fatty acids, aromatics, and hydrocarbons. In addition, the fermentation broth was found to have effects on flocculation and contain compounds that possess surface-active properties. Further investigations are needed to identify these chemicals responsible for these activities and develop ways to enhance coal biogasification based upon results obtained then.
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CUENA, LOMBRANA ALBA. "Integrated in situ and ex situ approach for Gentiana lutea L. ssp. lutea conservation." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266729.

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Gentiana lutea L. subsp lutea (hereafter G. lutea) is a long-lived geophyte, which has high medicinal value for the intensely bitter properties residing mainly in the root, being the main vegetable bitter employed in homeopathy and for the liqueurs production. G. lutea is presented in the Annex V of the Directive 92/43/EEC. In addition, it’s included in the List of endangered medicinal plants in the Annex D to the Council Regulation (EC) No. 338/97 of EU, whose purpose is the protection of plant species by control of their trade. Due to a lack of knowledge on the current G. lutea distributional information in Sardinia, Species Distribution Models (SDMs) could be even an important tool to limit search efforts by selecting the areas where field surveys are to be carried out for guiding discoveries of new localities and to evaluate the influence of extant and extinct localities. Once distribution knowledge was updated, further activities performed on representative localities, including ex situ and in situ studies were carried out. Firstly, our contribution to conserve this specie in Sardinia, included ex situ aspects that provided an alternative and complementary method for preventing immediate extinction and support further interventions. The experimental examination of the time when germination occurs in natural sites, the understanding of the seed behaviour in the soil and the investigation of the germination response under laboratory conditions. In particular, the isolated and on the boundary Sardinian population can differ genetically and morphologically from central populations because of their smaller population size and greater physical and ecological distances from the centre of the range, and may contain genotypes adapted to extreme environmental conditions; it is therefore important to check the effect on seed ecophysiology germination on small and spatial isolated populations. Previous studies have found that the germination of many mountain plants was promoted by cycles of cold-wet stratification that released seed dormancy in transient and permanent seed banks. In this way, dormancy played a key role in optimizing germination success by controlling the timing of germination. Thus, this research would contributed to this species conservation, suggesting the optimal protocol of germination and multiplication and, on the other hand, the information of the different kinds of seed dormancy. G. lutea is reported as being threatened not only by root harvesting practices, but also by global climatic warming due to its distribution, which is restricted mainly to the upper sectors of the mountains. Especially in mountain areas, climate warming is projected to shift species’ ranges to higher elevations. Plant species have responded to global warming through a generally accelerated phenology, enhanced growth and increased reproductive effort. Even fewer studies have addressed such response of the populations at the boundary of species range distributions which are thought to be particularly sensitive to climate change, hence it was evaluated the effect of anomalous temperatures (extremely warm) during the year of 2015 on phenology and reproductive successful. Monitoring the underlying drivers of this variation in phenological shifts will contribute to a mechanistic understanding of the biological effects of climate change. Finally, the criteria established by the IUCN that are widely employed as the gold standard for information on the conservation status of species were applied at regional scale for G. lutea. The assessment through the IUCN Criteria and Categories at global level was updated as Least Concern (LC) and at Italian level as Near Threatened (NT). Considering the regional level, the only previous assessment in Sardinia date to back to 1997 as Critically Endangered (CR), this work will contribute to an implementation of knowledge and conservation management for this taxon. An updating of local conservation status of G. lutea was thus provided by the analysis of its decline and comparing its potential suitable habitats based on the emissions scenarios presented by the Intergovernmental Panel on Climate Change (IPCC) for 2050 and 2070.
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Weibrecht, Irene. "Visualizing Interacting Biomolecules In Situ." Doctoral thesis, Uppsala universitet, Molekylära verktyg, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-151579.

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Intra- and intercellular information is communicated by posttranslational modifications (PTMs) and protein-protein interactions, transducing information over cell membranes and to the nucleus. A cells capability to respond to stimuli by several highly complex and dynamic signaling networks provides the basis for rapid responses and is fundamental for the cellular collaborations required in a multicellular organism. Having received diverse stimuli, being positioned at various stages of the cell cycle or, for the case of cancer, containing altered genetic background, each cell in a population is slightly different from its neighbor. However, bulk analyses of interactions will only reveal an average, but not the true variation within a population. Thus studies of interacting endogenous biomolecules in situ are essential to acquire a comprehensive view of cellular functions and communication. In situ proximity ligation assay (in situ PLA) was developed to investigate individual endogenous protein-protein interactions in fixed cells and tissues and was later applied for detection for PTMs. Progression of signals in a pathway can branch out in different directions and induce expression of different target genes. Hence simultaneous measurement of protein activity and gene expression provides a tool to determine the balance and progression of these signaling events. To obtain this in situ PLA was combined with padlock probes, providing an assay that can interrogate both PTMs and mRNA expression at a single cell level. Thereby different nodes of the signaling pathway as well as drug effects on different types of molecules could be investigated simultaneously. In addition to regulation of gene expression, protein-DNA interactions present a mechanism to manage accessibility of the genomic DNA in an inheritable manner, providing the basis for lineage commitment, via e.g. histone PTMs. To enable analyses of protein-DNA interactions in situ we developed a method that utilizes the proximity dependence of PLA and the sequence selectivity of padlock probes. This thesis presents new methods providing researchers with a set of tools to address cellular functions and communication in complex microenvironments, to improve disease diagnostics and to contribute to hopefully finding cures.
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Horner, Mariah. "Performing the Past in Situ." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36813.

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Johnny Drops the Bomb is a site-specific, historical play written to be performed in the Diefenbunker, a bomb shelter built to protect key members of the Canadian government in the event of a nuclear attack. As a practice-as-research project, Johnny Drops the Bomb explores the theories and techniques associated with performing history in situ: aura and atmosphere, empathy and witnessing, embodiment and being-in-the-world, proximity and site-specificity, and upsurges of the Real. As the written component of that practical project, this thesis contextualizes Johnny Drops the Bomb by situating it within these approaches, reflecting on the role that each technique played as I wrote, rehearsed, and ultimately performed it with two other actors.
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Chatelain, Clément. "Morphogenèse du mélanome in situ." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00794989.

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Le mélanome est le cancer de la peau le plus mortel. S'il est détecté de manière précoce il peut cependant être traité par simple excision et les chances de guérison sont alors très bonnes. Des algorithmes de diagnostic différentiels basés sur des critères morphologiques permettent ainsi de distinguer cette tumeur d'autres lésions bénignes présentes à la surface de la peau. Les mécanismes engendrant les formes et les microstructures caractéristiques d'un mélanome restent cependant pratiquement inconnus. L'objectif de ce travail est d'éclairer les processus morphogénétiques à l'oeuvre lors du développement des tumeurs mélanocytaires à l'aide des outils de la physique macroscopique. On commence par développer un modèle multiphase en couche mince pour décrire la croissance du mélanome dans l'épiderme. On montre analytiquement et numériquement l'existence d'une instabilité conduisant à l'apparition d'ondulations sur le contour d'une lésion initialement circulaire que l'on compare avec les irrégularités de contour fréquemment observées dans les mélanomes. L'identification des paramètres contrôlant cette instabilité permet ainsi de corréler les propriétés microscopiques de la tumeur à la forme et l'évolution macroscopique de la lésion. On montre ensuite la possibilité d'une décomposition spinodale dans cette classe de modèle multiphase, engendrant la formation d'agrégats de cellules tumorales. Le comportement du système aux temps long est cependant perturbée par les mécanismes de régulation de la prolifération cellulaire et un état d'équilibre est atteint où les agrégats de cellules forment une structure symétrique en points, en bandes ou en quadrillage. Ces prédictions permettent de mieux comprendre la présence de points et de globules pigmentés au sein de ces lésions, de taille, de forme et de répartition uniforme dans les tumeurs bénignes, et plus irrégulière dans les mélanomes. On s'intéresse finalement à la peau glabre et on illustre comment la géométrie particulière de l'épiderme dans ces régions influence l'aspect des tumeurs. En montrant comment le transport et la répartition de la mélanine est modifiée on propose ainsi une explication à l'apparition des bandes parallèles pigmentées et à la localisation des colonnes de mélanine. Afin d'étudier l'influence de la géométrie sur la répartition des cellules tumorales on développe un modèle multiphase en couche mince sur surface courbe. On propose ainsi un mécanisme expliquant la localisation d'agrégats cellulaires dans les crêtes épidermiques.
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Musmar, Sa'ed Awni. "In-situ thermal analysis probe." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102686.

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A new thermal analysis technique was developed and tested. It makes use of the improvements in heat transfer characteristics associated with recent advances in heat pipe technology. Heat is extracted from a liquid sample of a melt taken in-situ from within a vessel or furnace. The rate of heat extraction is such as to cause the sample to solidify. The technique was tested both in the laboratory and on an industrial scale (Grenville Castings, Perth, Ontario). Aluminum alloys including 356, 319, Al-xSi, Al-Si-Cu-xMg, and 6063 were subjected to various melt treatments and were used to carry out the tests. Classical thermal analysis was also carried out simultaneously under the same melt conditions using a preheated graphite cup.
The comparison showed that the new technique has great potential over classical thermal analysis. The major advantages of the new method are that it conducts the analysis inside the melt (since it is no longer necessary for a physical sample to be removed from the melt itself), it consumes less time and the cooling rate can be precisely controlled during the solidification process. Moreover, it produces curves of greater detail and of better resolution than conventional techniques. In fact, the detail is of such resolution that, in some cases, the cooling curves may be used to infer the chemical composition of certain components of the melt, a fact which equates to a form of rapid chemical analysis. The peaks in the signal which refer to intermetallic formation are of better resolution and more identifiable when the new technique is used. The size of the peaks obtained using the new probe is about three times greater than that obtained by the classical method. With this new technique it becomes possible to correlate the area below the intermetallic peak to the concentration of iron or copper in the melt. This is a feature which makes the new thermal analysis probe act as a rapid chemical analyzer for selected constituents.
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COUTINHO, BETANIA RODRIGUES. "CHARACTERIZATION, IN SITU TESTS, FLUORESCENCE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2760@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
O tema da dissertação, Caracterização de Áreas Contaminadas Através de Ensaios in Situ, aponta o estado-da-arte dos sensores que estão sendo adaptados ao conepenetrômetro, permitindo a detecção e o registro do poluente no subsolo e lençol freático.Talvez como uma conseqüência da atual conscientização da sociedade para o caráter emergencial no enfrentamento dos problemas relacionados à contaminação do subsolo,tem-se exigido uma significativa demanda de serviços especializados na caracterização dos agentes e processos de contaminação e nos procedimentos de remediação. A pesquisa apresenta técnicas de ensaio in situ para a caracterização de áreas contaminadas em função do contaminante que se quer detectar. O primeiro grande grupo abrange as tecnologias utilizadas na detecção dos hidrocarbonetos, em seguida estão agrupadas as técnicas de detecção dos compostos orgânicos voláteis e, finalmente, o terceiro grande grupo enfoca as técnicas utilizadas na detecção de metais pesados.Neste trabalho ensaios foram feitos em duas etapas: com o LIDAR-PUC e com o Fluorímetro, e são apresentados seus resultados, bem como as conclusões da pesquisa e algumas sugestões para estudos futuros, destacando-se as potencialidades e limitações de cada ensaio realizado.
The subject of the research, Characterization of Contaminated Areas by in Situ Tests, shows the state-of-art of the sensors that are being adapted to the conepenetrometer system, allowing for the detection and register of the polluent in the subsurface and water table.Perhaps as a consequence of the new conscientization of the society about the emergencial character in facing problems related to subsurface contamination, it has been claimed such a significative demand forward specialized services in characterization of agents and contamination processes, besides remediation procedures.In situ sampling techniques for the characterization of contaminated areas related to the targeted polluents are presented in this study. The first group covers technologies used in the detection of hydrocarbons, furthermore there are some techniques for the detection of volatiles organic compounds and, finally, the third group focuses the techniques used in the detection of heavy metals. In this work tests were done in two parts: with the LIDAR- PUC and with the Fluorimeter, and their results are presented as well the conclusions of the research and some suggestions for future works, principally the potentialities and limitations of each test done.
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Diogo, Bruno Miguel Moreira Marques. "Reciclagem in situ com cimento." Master's thesis, Edição do autor, 2008. http://hdl.handle.net/10316/15705.

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Larsson, Chatarina. "Single-molecule Detection in situ." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-98538.

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33

UZAN, ERIC. "Les carcinomes mammaires in situ." Amiens, 1992. http://www.theses.fr/1992AMIEM089.

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34

Graham, Aaron Robert. "In Situ Characterization of Unsaturated Soil Hydraulic Properties at the Maricopa Environmental Monitoring Site." Thesis, The University of Arizona, 2004. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0005_m_sip1_w.pdf&type=application/pdf.

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Yuen, Chi Ho. "Wear properties of Al-based composites reinforced with in-situ and ex-situ TiB₂ particulates." access abstract and table of contents access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21174374a.pdf.

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Thesis (M.Sc.)--City University of Hong Kong, 2004.
At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.
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36

Harada, Scott. "Issues related to the processing of ferroelectric nanostructures via ex situ and in situ methods." Thesis, Cranfield University, 2008. http://dspace.lib.cranfield.ac.uk/handle/1826/3000.

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This study investigates the impact of several processing parameters on the production of PZT and lead titanate nanostructures, by two different synthesis routes. The first aimed to produce freestanding, nanoscale PZT crystals via a simple, hydrothermal technique. Phase-pure, 52:48 PZT was synthesised within 2 hr at 160 °C in a hydrothermal autoclave. The morphology of the resultant crystals was cubic and micron-sized. Efforts were thus directed at reducing crystal size, by altering several processing conditions. Reaction time and temperature were found to have little effect on crystal size and instead resulted in incomplete reaction below the threshold values shown above. Introducing a 100% excess of Pb precursor led to an improvement in the faceting of the crystals, but again did not lead to a change in average crystal size. However, by using a 2% solution of the surfactant Triton-X, the average crystal size fell from 5 μm to 2 μm. The use of anatase TiO2 in the general hydrothermal procedure imposed a lower limit on the mineraliser concentration that was necessary for dissolution to occur. To overcome this restriction, a hybrid sol-gel/hydrothermal technique was attempted. This had the unexpected result of producing pyramidal microfibres that tapered to nano-sized points. Since the attempts to synthesise freestanding, nanoscale PZT crystals using the hydrothermal method were unsuccessful, work focussed on growing nanoislands on single crystal (100)- SrTiO3 substrates. Heteroepitaxial PZT films up to 1 μm thick, as well as micro- and nanoislands were observed, after extended 24 hr reactions at 160 °C. In some cases, the islands appeared to nucleate along scratches in the SrTiO3 substrate, leading to the formation of microwires up to a millimetre in length. Ferroelectric analysis of the microwires by PFM revealed them to be weakly piezoelectric. The second synthesis route to nanoscale ferroelectrics relied upon the solid phase reaction between Pb and Ti thin films to produce lead titanate. The optimum condition for the crystallisation of the perovskite phase was found to be 1 hr at 650 °C, under an air atmosphere. However, examination of the film morphology revealed large distortions and blistering across the surface. As such, it was not possible to acquire polarisation loop measurements, due to shorting between the top and bottom electrodes. EDAX confirmed that PbO vapour from the film was diffusing into the Si substrate leading to the formation of voids and the production of lead silicate glasses. Alternative adhesion layers for the Pt back electrodes were investigated, in an attempt to limit the diffusion of PbO. Electrical measurements on the films were made possible by substituting Zr for Ti. However, the shape of the hysteresis loops corresponded to a lossy dielectric as opposed to a ferroelectric response from the film. Films annealed on alternative substrates also suffered from blistering, but without the intrusion of PbO. This result suggested that the distortion present in the films was not as a consequence of the interaction between volatile species and the substrate. Instead, blistering and delamination was attributed to stresses generated during the transformation into the PbTiO3 perovskite phase. The solid phase synthesis method was extended to produce PbTiO3 nanoislands by utilising flash thermal evaporations. Deposition times below 1 s resulted in Pb nanoislands with a size range of 5 – 30 nm. Annealing the nanoislands under the same regime as used during the thin film experiments led to the loss of their morphology through melting. To overcome this problem an extended low temperature annealing was adopted. PFM was conducted on various nanoisland and thin film samples produced by the in situ technique. Nanoisland samples subjected to prolonged conventional annealings at 300 °C and brief hot plate annealings at 550 °C exhibited a non-zero piezoresponse. Definitive evidence of ferroelectricity in the nanoisland samples could not be demonstrated, however, as attempts to pole them were unsuccessful. PbTiO3 thin films produced by annealing Pb/Ti bilayers displayed clear c+ and c- ferroelectric domains that were mostly pinned by the grain boundaries. Little evidence of self-polarisation was found, since the average piezoresponse across the image was close to zero. Localised poling resulted in piezoresponse images showing the presence of intermediate contrast. This was interpreted as partial, 90 ° switching or evidence for “tail-to-tail” domain structure formation.
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Vineis, Christopher J. (Christopher Joseph) 1974. "Characterization of OMVPE-grown GaSb-based epilayers using in situ reflectance and ex situ TEM." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8452.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2001.
Includes bibliographical references (leaves 227-238).
The focus of this thesis was to investigate and characterize GaSb, GaInAsSb, and AlGaAsSb epilayers grown by organometallic vapor phase epitaxy (OMVPE). These epilayers were principally characterized using in situ spectral reflectance and ex situ transmission electron microscopy (TEM). An in situ spectral (380-1100 nm) reflectance monitoring system was designed and fitted to the OMVPE reactor. It was determined that longer wavelengths are more useful for quantitative growth rate analysis, while shorter wavelengths are more sensitive to the GaSb substrate oxide desorption process. It was also determined that the GaInAsSb and AlGaAsSb alloy compositions could be determined accurately using in situ reflectance ratios. Use of the in situ reflectance monitor to efficiently perform necessary reactor/growth calibrations was also demonstrated. Analytic functions were used to model the refractive indices of GaSb, AlGaAsSb, and GaInAsSb. Specifically, Adachi's Model Dielectric Function [1, 2] was curve-fit to data for GaSb between 400 and 1000 nm, and fourth-order polynomials were fit to data for GaSb and GaInAsSb between 1 and 3 gnm. A linear interpolation of binary functions was used to generate a refractive index model for AlGaAsSb between 1 and 3 m as a function of Al fraction. These models were helpful in interpreting in situ reflectance data, and also in designing distributed Bragg reflectors. Phase separation in GaInAsSb was studied using TEM. A wide range of microstructures was observed, from nearly homogeneous to strongly phase separated.
(cont.) It was seen that in phase separated samples, the composition modulations typically created and coupled to morphological perturbations in the surface. One interesting manifestation of the phase separation was the spontaneous formation of a natural superlattice (period typically 10-30 nm) throughout the epilayer. This superlattice had two variants: one parallel to the growth surface, and one tilted with respect to the growth surface. It was discovered that the tilted superlattice was coupled to surface to relieve surface strain associated with the superlattice ...
by Christopher J. Vineis.
Ph.D.
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38

Smith, A. J. "In-situ and ex-situ studies of heteroatom substituted nanoporous materials using advanced radiation techniques." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1419865/.

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The work described in this thesis is concerned with the development of in-situ and ex-situ methods associated with synchrotron radiation techniques to understand the formation of nanoporous materials. The aim of this work is to expand knowledge of the mechanistic aspects of formation and growth of heteroatom substituted nanoporous systems to enable the development of new synthetic strategies for the production of specific nanoporous materials. in-situ small angle X-ray scattering was widely used for this purpose to study the formation of zeolite A and silicalite systems. New in-situ cells were developed to carry out the measurements. The results obtained clearly showed the growth depends on the ageing time of the precursor gel, constituents and temperature. More importantly a homogeneous nucleation and growth was observed for zeolite A and a more complex process was seen to take place for silicalite. Ti and Ge containing silicalite systems were studied in detail. X-ray absorption spectroscopic studies provided the clear evidence for Ge incorporation into the framework of silicalite, prior to the crystallisation. A new water soluble titanium precursor compound was developed to synthesise titanosilicate system containing ca 5 wt% titanium. XAS and IR were used for characterisation, and this material was also tested for the catalytic epoxidation of alkene. Finally, a novel method of preparing silicalite films/membranes and metal-substituted analogues was developed. Ti and Fe containing silicalite films were successfully prepared and characterised using a suite of X-ray techniques.
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39

Han, Zhi-Yan. "Contribution à l'étude des récepteurs nicotiniques de l'acétylcholine dans le cerveau du singe rhésus." Paris 6, 2003. http://www.theses.fr/2003PA066152.

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40

Cheng, Yin [Verfasser], and Ingo [Akademischer Betreuer] Krossing. "In situ synchrotron radiation computed laminography for materials failure analysis = In-situ Synchrotron-Laminographie für Materialfehleranalyse." Freiburg : Universität, 2013. http://d-nb.info/1123479097/34.

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41

Navas, Hugo. "Mécanismes de croissance des nanotubes de carbone étudiés par spectroscopie Raman in situ et ex situ." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20048/document.

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Ce travail expérimental porte sur l'influence des paramètres de synthèse de nanotubes de carbone par CVD sur leurs caractéristiques structurales. Cette étude repose sur des analyses ex situ et in situ par spectroscopie Raman d'échantillons synthétisés sous diverses conditions de croissance. Une étude sur des films de cobalt oxydés a montré qu'il existe une variation de la pression seuil pour la croissance de nanotubes de carbone en fonction de l'épaisseur de cobalt que nous proposons d'attribuer à une pression seuil de réduction des particules.Une étude des bandes D et G' nous a permis d'attribuer les composantes basses fréquences aux nanotubes mono-feuillets et les composantes hautes fréquences à des espèces carbonées co-produites lors de la synthèse. Cette nouvelle approche a permis une étude plus fine des défauts et la proposition d'un modèle de création des défauts dans les nanotubes synthétisés par CVD. Enfin, une étude systématique des RBM nous a permis de mettre en évidence des processus favorisant la croissance de nanotubes mono-feuillets de petits ou de moyens diamètres. Ainsi, le contrôle de l'épaisseur de catalyseur, de la nature du précurseur carboné, de sa pression partielle ou encore de la température de synthèse permet de contrôler la distribution en diamètre des nanotubes mono-feuillets
This experimental work deals with the influence of CVD growth parameters on carbon nanotube structural properties. The study is based on in situ and ex situ Raman spectroscopy on samples synthesized under various conditions of growth. A work on oxidized cobalt films showed that the threshold pressure for nanotube growth depends on the thickness of the cobalt film. We assign this pressure to a threshold pressure of reduction. A study of the D-band and G'-band allowed to assign low-frequency components to SWNT and high-frequency components to carbonaceous co-products of synthesis. This new approach allowed a fine study of defects which led to a model for defect creation in SWNT grown by CVD. A systematic study of RBM showed the processes leading to the preferential growth of small- or medium-diameter SWNT. Thus, control of catalyst thickness, of carbonaceous precursor nature and partial pressure or of synthesis temperature allows to control the diameter distribution of SWNT
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42

Pacheco, Pablo. "Estudos fisiológicos como subsídio para a conservação in situ e ex situ de Cecropia glazioui Sneth." Florianópolis, SC, 2004. http://repositorio.ufsc.br/xmlui/handle/123456789/87078.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-graduação em Biologia Vegetal
Made available in DSpace on 2012-10-21T14:18:58Z (GMT). No. of bitstreams: 1 212041.pdf: 393216 bytes, checksum: 99702cb7b73af04b4cd5dec1bb8ac69d (MD5)
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43

Huguet-Garcia, Juan Francisco. "In situ and ex situ characterization of the ion-irradiation effects in third generation SiC fibers." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066221/document.

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L'utilisation des fibres SiC Tyranno SA3 (TSA3) et Hi Nicalon S (HNS) pour le renforcement de composites céramiques dédiées aux applications nucléaires impose l'étude de leur stabilité microstructurale et de leur comportement mécanique sous irradiation. La cinétique d'amorphisation des fibres a été étudiée et comparée à celle d'un matériau modèle, 6H-SiC monocristallin, sans que des différences significatives puissent être observées. La dose seuil d'amorphisation totale a été évaluée à ~0,4 dpa à température ambiante et aucune amorphisation complète n'a pas être obtenue pour des températures d'irradiation supérieures à 200 ºC. Les échantillons amorphes ont ensuite été recuits thermiquement ce qui a conduit, pour des températures élevées, à leur recristallisation mais également à une fissuration et une délamination de la zone irradiée. Ce processus d'endommagement était activé thermiquement avec une énergie d'activation de 1,05 eV. En ce qui concerne le comportement mécanique, le fluage d'irradiation des fibres TSA3 a été étudié en utilisant une machine de traction in situ implantée sur deux plateformes d'irradiation aux ions. On montre que sous irradiation ces fibres se déforment en fonction du temps avec des chargements thermique et mécanique où le fluage thermique est négligeable. Cette déformation est plus élevée pour les faibles températures d'irradiation en raison d'un couplage entre le gonflement et le fluage d'irradiation. Pour des températures voisines de 1000 ºC, le gonflement devient négligeable ce qui permet l'étude spécifique du fluage d'irradiation dont la vitesse de déformation présente une dépendance linéaire au flux d'ions
The use of Tyranno SA3 (TSA3) and Hi Nicalon S (HNS) SiC fibers as reinforcement for ceramic composites for nuclear applications requires the characterization of its structural stability and mechanical behavior under irradiation. Ion-amorphization kinetics of these fibers have been studied and compared to the model material, i.e. 6H-SiC single crystals, with no significant differences. For all samples, full amorphization threshold dose yields ~0.4 dpa at room temperature and complete amorphization was not achieved for irradiation temperatures over 200 ºC. Successively, ion-amorphized samples have been thermally annealed. It is reported that thermal annealing at high temperatures not only induces the recrystallization of the ion-amorphized samples but also causes cracking and delamination. Cracking is reported to be a thermally driven phenomenon characterized by activation energy of 1.05 eV. Regarding the mechanical irradiation behavior, irradiation creep of TSA3 fibers has been investigated using a tensile device dedicated to in situ tests coupled to two different ion-irradiation lines. It is reported that ion-irradiation (12 MeV C4+ and 92 MeV Xe23+) induces a time-dependent strain under loads where thermal creep is negligible. In addition, irradiation strain is reported to be higher at low irradiation temperatures due to a coupling between irradiation swelling and irradiation creep. At temperatures near 1000 ºC, irradiation swelling is minimized hence allowing the characterization of the irradiation creep. Irradiation creep rate is characterized by a linear correlation between the ion flux and the strain rate and square root dependence with the applied load
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44

Huguet-Garcia, Juan Francisco. "In situ and ex situ characterization of the ion-irradiation effects in third generation SiC fibers." Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066221.

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L'utilisation des fibres SiC Tyranno SA3 (TSA3) et Hi Nicalon S (HNS) pour le renforcement de composites céramiques dédiées aux applications nucléaires impose l'étude de leur stabilité microstructurale et de leur comportement mécanique sous irradiation. La cinétique d'amorphisation des fibres a été étudiée et comparée à celle d'un matériau modèle, 6H-SiC monocristallin, sans que des différences significatives puissent être observées. La dose seuil d'amorphisation totale a été évaluée à ~0,4 dpa à température ambiante et aucune amorphisation complète n'a pas être obtenue pour des températures d'irradiation supérieures à 200 ºC. Les échantillons amorphes ont ensuite été recuits thermiquement ce qui a conduit, pour des températures élevées, à leur recristallisation mais également à une fissuration et une délamination de la zone irradiée. Ce processus d'endommagement était activé thermiquement avec une énergie d'activation de 1,05 eV. En ce qui concerne le comportement mécanique, le fluage d'irradiation des fibres TSA3 a été étudié en utilisant une machine de traction in situ implantée sur deux plateformes d'irradiation aux ions. On montre que sous irradiation ces fibres se déforment en fonction du temps avec des chargements thermique et mécanique où le fluage thermique est négligeable. Cette déformation est plus élevée pour les faibles températures d'irradiation en raison d'un couplage entre le gonflement et le fluage d'irradiation. Pour des températures voisines de 1000 ºC, le gonflement devient négligeable ce qui permet l'étude spécifique du fluage d'irradiation dont la vitesse de déformation présente une dépendance linéaire au flux d'ions
The use of Tyranno SA3 (TSA3) and Hi Nicalon S (HNS) SiC fibers as reinforcement for ceramic composites for nuclear applications requires the characterization of its structural stability and mechanical behavior under irradiation. Ion-amorphization kinetics of these fibers have been studied and compared to the model material, i.e. 6H-SiC single crystals, with no significant differences. For all samples, full amorphization threshold dose yields ~0.4 dpa at room temperature and complete amorphization was not achieved for irradiation temperatures over 200 ºC. Successively, ion-amorphized samples have been thermally annealed. It is reported that thermal annealing at high temperatures not only induces the recrystallization of the ion-amorphized samples but also causes cracking and delamination. Cracking is reported to be a thermally driven phenomenon characterized by activation energy of 1.05 eV. Regarding the mechanical irradiation behavior, irradiation creep of TSA3 fibers has been investigated using a tensile device dedicated to in situ tests coupled to two different ion-irradiation lines. It is reported that ion-irradiation (12 MeV C4+ and 92 MeV Xe23+) induces a time-dependent strain under loads where thermal creep is negligible. In addition, irradiation strain is reported to be higher at low irradiation temperatures due to a coupling between irradiation swelling and irradiation creep. At temperatures near 1000 ºC, irradiation swelling is minimized hence allowing the characterization of the irradiation creep. Irradiation creep rate is characterized by a linear correlation between the ion flux and the strain rate and square root dependence with the applied load
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45

Stewart, Isobel Margaret Campbell. "Performance as relationship : memory, materiality and process in the site-specific practice of in situ." Thesis, De Montfort University, 2007. http://hdl.handle.net/2086/4226.

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46

Gutierrez, Diana, and Diana Gutierrez. "In-Situ Biosequestration for Remediation of Uranium in Groundwater at the Monument Valley UMTRA Site." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620727.

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The Monument Valley UMTRA Site is a former uranium mining site that is located in Cane Valley, Arizona. The mining that occurred there from 1943 to 1968 created a groundwater contaminant plume that consists of nitrate, sulfate, and uranium. There are only a few viable methods for remediation of these types of contaminants occurring in large, deep plumes. Monitored natural attenuation is a popular approach because it is a green and low-cost alternative. However, it is often ineffective without some form of supplemental enhancement. In-situ biosequestration is one method of enhanced attenuation, which involves injecting an electron- donating substrate that will promote microbial activity and sequester contaminants by bioprecipitation, biomineralization, and enhanced adsorption. Prior tests conducted at the Monument Valley site in the center of the plume using ethanol as the electron donor proved effective in the treatment of nitrate, sulfate, and uranium. Subsequent pilot scale tests are being conducted in the source zone of the Monument Valley Site to further investigate the feasibility and effectiveness of using in-situ biosequestration for treatment of uranium contaminated groundwater. The preliminary results of these tests are discussed.
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47

Reyes, Nohely, and Nohely Reyes. "Pilot-Scale In-Situ Biosequestration of Uranium in Groundwater at the Monument Valley Umtra Site." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/625132.

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In-situ biosequestration, wherein electron-donating substrates are injected to promote microbial-associated sequestration of contaminants, is one promising enhanced-attenuation technique for remediation of groundwater containing arsenic, uranium, selenium, and similar constituents. A pilot-scale test of in-situ biosequestration for uranium in groundwater is in progress at a former uranium mining site in Monument Valley, Arizona. Approximately 20 m3 of 0.5% ethanol solution was injected into a test zone of the alluvial aquifer. Groundwater was sampled periodically before, during, and after the injection. The relevant constituents, such as uranium, nitrogen species, sulfur species, anions/cations, ethanol, and sulfur and nitrogen isotopes, were monitored to characterize the biosequestration process. Sediment samples were also collected before and twice after the injection for monitoring change in sediment properties, mineral geochemical composition, microbial community composition, and microbial activity. The results of the test are compared to those of a prior test conducted at a different location of the site to evaluate the impact of water-quality parameters on sequestration effectiveness.
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48

MESCHINI, Roberto. "La musealizzazione in situ: Strategie e tecniche di valorizzazione e di comunicazione dei siti archeologici." Doctoral thesis, Università degli studi di Ferrara, 2009. http://hdl.handle.net/11392/2388684.

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In recent years we’ve encountered new attention regarding musealizzazione on site of archaeological heritage, in Italy as well as at international level. A wide array of technical meetings and conferences have brought the matter to attention worldwide. We are in need of a definition for the main subject of this issue, in order to acknowledge the area involved by this research. Archaeology and musealizzazione disciplines have points in common regarding protection and enhancement of assets. An archaeological site is intrinsically a three dimensional portion of space in which we can notice a wide variety of physical transformations due both to nature and mankind, with the result of a place where space and time are built in as one. Usually an archaeological site undergoes two different stages, conservation and musealizzazione, being divided in movable and non movable components. The first ones are typically assigned to conservation in environments not directly referring to the site, guaranteeing an high level of conservation and enhancement. Non movable components remain in place where they have been found, creating a portion of ground called “site”. Separation of these components usually distorts the completeness of finding on a large scale, as well as comprehension of an archaeological site both historically and anthropologically. Musealizzazione on site is therefore necessary in order to protect assets and return them to the community. Involvement of different professional figures must emerge in every aspect of enhancement of an archaeological asset, but mainly during the process from excavation through enhancement. This procedure can be associated to the process intending to realize an asset in other fields. From this similarity rises an identification that shall be called “archaeological process”. “ The Archaeological process” is the procedure that an archaeological area performs from its finding to its enhancement, representing throughout musealizzazione on site the whole process of enhancement of movable and non movable assets, including practices (excavation, analysis, cataloguing, restoration) performed to make them usable and perceptible by the community. “The Archaeological process” surely needs continuous technological innovation regarding protection and communication of findings, not only about materials used in the process but also about different communication aspects of findings and of site itself.
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49

Boudreault, Nathalie. "Quatre dispositifs in situ pour une meilleure compréhension de l'oeuvre du peintre Arthur Villeneuve /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 2001. http://theses.uqac.ca.

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50

Darmarajan, Suresh. "Chemistry of in-situ phosphating coating /." [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18553.pdf.

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