973 resultados para condensation symbol


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Thiol-functionalized mesoporous ethane-silicas with large pore were synthesized by co-condensation of 1,2-bis(trimethoxy-sily)ethane (BTME) with 3-mercaptopropyltrimethoxysilane (MPTMS) using nonionic oligomeric polymer C1H (OCH(2)-CH(2))(10)OH (Brij-76) or poly(alkylene oxide) block copolymer (P123) as surfactant in acidic medium. The results of powder X-ray diffraction (XRD), nitrogen gas adsorption, and transmission electron microscopy (TEM) show that the resultant materials have well-ordered hexagonal mesoscopic structure with uniform pore size distributions. (29)Si MAS NNR, (13)C CP-MAS NMR. FT-IR, and UV Raman spectroscopies confirm the attachment of thiol functionalities in the mesoporous ethane-sificas. The maximum content of the attached thiol group (-SH) in the mesoporous framework is 2.48mmol/g. The ordered mesoporous materials are efficient Hg(2+) adsorbents with almost every -SH site accessible to Hg(2+). In the presence of various kinds of heavy metal ions such as Hg(2+), Cd(2+), Zn(2+), Cu(2+) and Cr(3+), the materials synthesized using poly(alkylene oxide) block cooollxmier (Pluronic 123) g(2+), as surfactant show almost similar affinity to Hg(2+), Cd(2+), and Cr(3+), while the materials synthesized using ofigomeric polymer C(18)H(37)(OCH(2)CH(2))(10)OH (Brij-76) as surfactant exhibit high selectivity to Hg(2+). (C) 2004 Elsevier Inc. All rights reserved.

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A novel hybrid organic-inorganic silica-based monolithic column possessing phenyl ligands for reversed-phase (RP) capillary electrochromatography (CEC) is described. The monolithic stationary phase was prepared by in situ co-condensation of tetraethoxysilane (TEOS) with phenyltriethoxysilane (PTES) via a two-step catalytic sol-gel procedure to introduce phenyl groups distributed throughout the silica matrix for chromatographic interaction. The hydrolysis and condensation reactions of precursors were chemically controlled through pH variation by adding hydrochloric acid and dodecylamine, respectively. The structural property of the monolithic column can be easily tailored through adjusting the composition of starting sol solution. The effect of PTES/TEOS ratios on the morphology of the created stationary phases was investigated. A variety of neutral and basic analytes were used to evaluate the column performance. The CEC columns exhibited typical RP chromatographic retention mechanism for neutral compounds and had improved peak shape for basic solutes.

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The surfactant assistant syntheses of sulfonic acid functionalized periodic mesoporous organosilicas with large pores are reported. A one-step condensation of tetramethoxysilane (TMOS) with 1,2-bis(trimethoxysilyi)ethane (BTME) and 3-mercaptopropyltrimethoxysilane (MPTMS) in highly acidic medium was performed in the presence of triblock copolymer Pluronic P123 and inorganic salt as additive. During the condensation process, thiol (-SH) group was in situ oxidized to sulfonic acid (-SO3H) by hydrogen peroxide (30 wt % H2O2). X-ray diffraction studies along with nitrogen and water sorption analyses reveal the formation of stable, highly hydrophobic, and well-ordered hexagonal mesoscopic structures in a wide range of -CH2CH2-concentrations in the mesoporous framework. The resultant materials were also investigated by Si-29 MAS and C-13 CP MAS NMR, thermogravimetric analyses, UV-Raman spectroscopy, and FT-IR spectroscopy. The role of the bridged organic group on the hydrothermal stability of the mesoporous materials was established, which revealed an enhancement in hydrothermal stability of the materials with incorporation of the bridged organic groups in the network. The catalytic performance of -SO3H functionalized mesoporous materials was investigated in the esterification of ethanol with acetic acid, and the results demonstrate that the ethane groups incorporated in the mesoporous framework have a positive influence on the catalytic behavior of the materials.

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Steam reforming of ethanol over CuO/CeO2 was studied. Acetaldehyde and hydrogen were mainly produced at 260degreesC. At 380degreesC, acetone was the main product, and 2 mol of hydrogen was produced from 1 mol of ethanol. The formation of hydrogen accompanied by the production of acetone was considered to proceed through the following, consecutive reactions: dehydrogenation of ethanol to acetaldehyde. aldol condensation of the acetaldehyde, and the reaction of the aldol with the lattice oxygen [O(s)] on the catalyst to form a surface intermediate, followed by its dehydrogenation and decarboxylation. The overall reaction was expressed by2C(2)H(5)OH + H2O --> CH3COCH3 + CO2 + 4H(2). Ceria played an important role as an oxygen supplier. The addition of MgO to CuO/CeO2 resulted in the production of hydrogen at lower temperatures by accelerating aldol condensation. (C) 2004 Elsevier B.V. All rights reserved.

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Roberts, Owen, 'Waterworks and commemoration: purity, rurality, and civic identity in Britain, 1880-1921', Continuity and Change (2007) 22(2) pp.305-325 RAE2008

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EI Mikhailova, SP Sosnikhina, GA Kirillova, OA Tikholiz, VG Smirnov, RN Jones and G Jenkins (2001). Nuclear dispositions of subtelomeric and pericentromeric chromosomal domains during meiosis in asynaptic mutants of rye (Secale cereale L.). Journal of Cell Science, 114 (10), 1875-1882. Sponsorship: Russian Foundation for Basic Research (grants 00-04-48522/ 99-04-48182) RAE2008

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Celem artykułu jest przedstawienie aplikacji zastosowania na krajowym poziomie stosowania przepisów unijnych koncepcji wykładni derywacyjnej Macieja Zielińskiego. Podjęto w nim próbę udzielenia odpowiedzi na pytanie o wzajemne relacje przepisów prawnych ustanowionych przez socjologicznie różnych prawodawców do norm postępowania odtwarzanych w procesie wykładni w oparciu o analizę syntaktyczną oraz treściową krajowych i unijnych przepisów prawnych z różnych gałęzi prawa. Zastosowanie założeń koncepcji derywacyjnej do rozstrzygania spraw z elementem unijnym prowadzi do konkluzji, że zarówno zjawisko rozczłonkowania (na poziomie syntaktycznym oraz treściowym), jak również kondensacja norm postępowania w przepisach prawnych przebiegać może w sposób krzyżowy pomiędzy aktami prawnymi ustanowionymi przez różnych prawodawców socjologicznych (faktycznych). Ponadto, analiza szczególnego typu unijnych przepisów bezpośrednio skutecznych, prima facie stanowiących źródło obowiązku normatywnego wyłącznie dla państw członkowskich, w świetle założeń koncepcji wykładni derywacyjnej uświadamia, że przepisy te stanowią w gruncie rzeczy modelową egzemplifikację zjawiska kondensacji elementów norm prawnych. Przeprowadzona analiza relacji zakresowych przepisów prawnych do norm postępowania wykazuje stosowalność koncepcji derywacyjnej w procesie rozstrzygania spraw z elementem unijnym. Koncepcja ta wyjaśnia szczególnie złożone problemy wykładni prawa w sprawach z elementem unijnym oraz dostarcza teorii i praktyce instrumentarium do ich rozwiązywania. Jej zastosowanie unaocznia jednocześnie złożoną strukturę systemu prawa, którą charakteryzuje zjawisko hybrydyzacji.

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Francja i Niemcy przez stulecia walczyły o zdobycie władzy i przejęcie wpływów na kontynencie europejskim i traktowały siebie nawzajem jako największe zagrożenie. Jednak tragiczna pierwsza połowa XX wieku przyniosła z jednej strony pragnienie zapewnienia, iż okropności wojny już nigdy się nie powtórzą, a z drugiej strony poczucie, że nieodzowna jest zmiana dwustronnych stosunków panujących między Berlinem a Paryżem. Konieczność stworzenia przestrzeni wolności i współpracy doprowadziła niegdysiejszych wrogów do stworzenia idei integracji najważniejszych części gospodarki. Pomysł zjednoczenia krajów Europy Zachodniej przekształcił się w kolejnych latach w symbol zaangażowania francusko-niemieckiego. Dwie republiki stały się rdzeniem europejskiej współpracy i spiritus movens zmian politycznych, ekonomicznych i instytucjonalnych w powojennej Europie. Po upadku komunizmu w 1989 roku ich rola zyskała nowy wymiar w odmiennych warunkach geopolitycznych - od momentu podpisania Traktatu z Maastricht w 1992 roku francusko-niemiecki duet powiększył swe znaczenie i wpływ na politykę nowej Unii Europejskiej. Realizacja zapisów Traktatu z Maastricht i kolejnych dokumentów, w tym Traktatu z Lizbony, koncentracja na kwestiach reform instytucjonalnych, jak również przygotowania do wschodniego rozszerzenia UE mogą być rozpatrywane jedynie w odniesieniu do wspólnych działań prowadzonych przez nadreński tandem. Realizacja trzech filarów integracji: współpracy w wymiarze ekonomicznym i społecznym, wspólnej polityki zagranicznej i bezpieczeństwa, jak również współpracy policyjnej i sądowej w sprawach karnych, podkreślają znaczenie couple franco-allemand i zwracają uwagę na rolę lidera, jaką Paryż i Berlin odgrywają w dziedzinie integracji.

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Wydział Historyczny: Instytut Historii Sztuki

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Celem niniejszego artykułu jest wskazanie i przedyskutowanie (z perspektywy filozofii komunikacji i teorii komunikacji) kilku konsekwencji wynikających z badań nad fenomenem komunikacji. Oprócz zagadnień związanych z filozoficznym ujęciem procesu komunikacji podejmuje się również problematykę wyłonienia się myślenia metafizycznego w starożytnej Grecji. Artykuł ten jest próbą wskazania warunków, które należy spełnić, aby prowadzić filozoficznie uprawnioną refleksję nad procesem komunikacji. Całość została podzielona na trzy główne działy: w pierwszym są prezentowane dwa poziomy rekonstrukcji sytuacji komunikacyjnej w kulturze archaicznej; w drugim rozważa się zagadnienie początków relacji symbolizowania oraz zjednoczenia myślenia i działania. Trzecia część poświęcona jest źródłom myślenia metafizycznego oraz symboliczności komunikacji. Najistotniejszy wniosek wynikający z rozważań zawarty w artykule dotyczy nie-symbolicznego ujęcia procesów komunikacyjnych.

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Tolkien’s oeuvre and its problematic relationships with classical tradition serve in my paper as an illustration of the diverse approaches, methods, and styles of lecture concerning the nature of literary allusivity. As a point of departure in the paper has been taken the reflection on the common phrase about “antiquity in something” deployed broadly in the reception studies. T he questions raised here are as follows: what does precisely “in” mean in that metaphor? O r, to put it in more general terms, when an allusion to another text can be treated as an inherent part of interpretation? Answer to these questions was possible due to U mberto E co’s statements in the well-known dispute relating to the interpretation and overinterpretation; in conclusion I was trying to show that his criterion of textual economy in interpretation justifies somehow (as I believe) the new look on the essential T olkien’s symbol, i.e. the ring of power, as a symbol of the R oman imperial rule. This means (in the context of the translatio imperii and cultural change from pagan to Christian empire) that The Lord of the Rings can be seen in a way as a novelistic version of Augustine’s The City of God.

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One can say that our times are dominated by visual communication. Usually all day long we have been faced by various pictures, visual forms and symbols. According to the subject of the book 'Archaeology-Culture-Ideologies' I found it interesting to pay attention to the problem of visual representation, or better say visual symbols in nowadays communication and culture, their meaning and importance. From this point of view I would like to show the role of archaeologists who discover, interpret or even create some of them. The subject is not new of course, but the most often it is taken into consideration by the scholars who practice in social anthropology or philosophy and quite rarely it appear in studies of archaeologies, especially in Polish tradition. In my opinion the subject concerning visual symbols communication and archaeology arise several important questions that are also valid for the theme of book 'Archaeology-Culture-Ideologies'. The first is socio-cultural role of our discipline, next the danger of political and propaganda misuse of the results of archaeological research and then also commercialisation of the archaeological activities. The problem of visualisation and visual-communication can be the matter of various studies. In my paper from the beginning I would like to present the general view concerning visual symbols and figural motifs and the main ideas and approaches to study them from different humanistic perspectives. Then in my presentation I am going to discuss the question why in our culture the visual symbols and representations became so popular – compare to other ways of human expression, for example verbal symbol communication. I would like to see the problem in historical perspective as well. There are a lot of evidences, which support the statement about the power of visual symbols in history. In ancient times for example Horace in 'Ars Poetica' suggested that human mind usually is much more impressed by eyes than by ears. In my opinion that is quite often in human culture that visual impression is before mental one. Visual representations and symbols are very powerful, they can show and communicate various phenomena, they act immediately and quite often in easily way they can associate. So for archaeological research it could be very important to make some studies concerning the ancient symbols and general iconography and also it would be grateful to make some attempts for the study what kind of potential meaning could have visual symbols. In my paper I can only make some general statement about it. But the most important for the topic is reflection on prehistoric and ancient visual symbols and representation and their presence in contemporary culture. So after some general statements concerning the visual symbols examined from various perspectives finally I would like to point out with support of some examples how ancient and prehistoric visual symbols and images are still used and captured by contemporary culture and what is or should be the role of archaeologists activity concerning this matter.

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The present work examines the beginnings of ancient hermeneutics. More specifically, it discusses the connection between the rise of the practice of allegoresis, on the one hand, and the emergence of the first theory of figurative language, on the other. Thus, this book investigates the specific historical and cultural circumstances that enabled the ancient Greeks not only to discover the possibility of allegorical interpretation, but also to treat figurative language as a philosophical problem. By posing difficulties in understanding the enigmatic sense of various esoteric doctrines, poems, oracles and riddles, figurative language created the context for theoretical reflection on the meaning of these “messages”. Hence, ancient interpreters began to ponder over the nature and functions of figurative (“enigmatic”) language as well as over the techniques of its proper use and interpretation. Although the practice of allegorical interpretation was closely linked to the development of the whole of ancient philosophy, the present work covers only the period from the 6th to the 4th century B.C. It concentrates, then, on the philosophical and cultural consequences of allegoresis in the classical age. The main thesis advocated here has it that the ancient Greeks were in-clined to regard allegory as a cognitive problem rather than merely as a stylistic or a literary one. When searching for the hidden meanings of various esoteric doc-trines, poems, oracles and riddles, ancient interpreters of these “messages” assumed allegory to be the only tool suitable for articulating certain matters. In other words, it was their belief that the use of figurative language resulted from the necessity of expressing things that were otherwise inexpressible. The present work has been organized in the following manner. The first part contains historical and philological discussions that provide the point of departure for more philosophical considerations. This part consists of two introductory chapters. Chapter one situates the practice of allegorical interpretation at the borderline of two different traditions: the rhetorical-grammatical and the hermeneutical. In order to clearly differentiate between the two, chapter one distinguishes between allegory and allegoresis, on the one hand, and allegoresis and exegesis, on the other. While pointing to the conventionality (and even arbitrariness) of such distinctions, the chapter argues, nevertheless, for their heuristic usefulness. The remaining part of chapter one focuses on a historical and philological reconstruction of the most important conceptual tools of ancient hermeneutics. Discussing the semantics of such terms as allēgoría, hypónoia, ainigma and symbolon proves important for at least two crucial reasons. Firstly, it reveals the mutual affinity between allegoresis and divination, i.e., practices that are inherently connected with the need to discover the latent meaning of the “message” in question (whether poem or oracle). Secondly, these philological analyses bring to light the specificity of the ancient understanding of such concepts as allegory or symbol. It goes without saying that antiquity employed these terms in a manner quite disparate from modernity. Chapter one concludes with a discussion of ancient views on the cognitive value of figurative (“enigmatic”) language. Chapter two focuses on the role that allegoresis played in the process of transforming mythos into logos. It is suggested here that it was the practice of allegorical interpretation that made it possible to preserve the traditional myths as an important point of reference for the whole of ancient philosophy. Thus, chapter two argues that the existence of a clear opposition between mythos into logos in Preplatonic philosophy is highly questionable in light of the indisputable fact that the Presocratics, Sophists and Cynics were profoundly convinced about the cognitive value of mythos (this conviction was also shared by Plato and Aristotle, but their attitude towards myth was more complex). Consequently, chapter two argues that in Preplatonic philosophy, myth played a function analogous to the concepts discussed in chapter one (i.e., hidden meanings, enigmas and symbols), for in all these cases, ancient interpreters found tools for conveying issues that were otherwise difficult to convey. Chapter two concludes with a classification of various types of allegoresis. Whilst chapters one and two serve as a historical and philological introduction, the second part of this book concentrates on the close relationship between the development of allegoresis, on the one hand, and the flowering of philosophy, on the other. Thus, chapter three discusses the crucial role that allegorical interpretation came to play in Preplatonic philosophy, chapter four deals with Plato’s highly complex and ambivalent attitude to allegoresis, and chapter five has been devoted to Aristotle’s original approach to the practice of allegorical interpretation. It is evident that allegoresis was of paramount importance for the ancient thinkers, irrespective of whether they would value it positively (Preplatonic philosophers and Aristotle) or negatively (Plato). Beginning with the 6th century B.C., the ancient practice of allegorical interpretation is motivated by two distinct interests. On the one hand, the practice of allegorical interpretation reflects the more or less “conservative” attachment to the authority of the poet (whether Homer, Hesiod or Orpheus). The purpose of this apologetic allegoresis is to exonerate poetry from the charges leveled at it by the first philosophers and, though to a lesser degree, historians. Generally, these allegorists seek to save the traditional paideia that builds on the works of the poets. On the other hand, the practice of allegorical interpretation reflects also the more or less “progressive” desire to make original use of the authority of the poet (whether Homer, Hesiod or Orpheus) so as to promote a given philosophical doctrine. The objective of this instrumental allegoresis is to exculpate philosophy from the accusations brought against it by the more conservative circles. Needless to say, these allegorists significantly contribute to the process of the gradual replacing of the mythical view of the world with its more philosophical explanation. The present book suggests that it is the philosophy of Aristotle that should be regarded as a sort of acme in the development of ancient hermeneutics. The reasons for this are twofold. On the one hand, the Stagirite positively values the practice of allegoresis, rehabilitating, thus, the tradition of Preplatonic philosophy against Plato. And, on the other hand, Aristotle initiates the theoretical reflection on figurative (“enigmatic”) language. Hence, in Aristotle we encounter not only the practice of allegoresis, but also the theory of allegory (although the philosopher does not use the term allēgoría). With the situation being as it is, the significance of Aristotle’s work cannot be overestimated. First of all, the Stagirite introduces the concept of metaphor into the then philosophical considerations. From that moment onwards, the phenomenon of figurative language becomes an important philosophical issue. After Aristo-tle, the preponderance of thinkers would feel obliged to specify the rules for the appropriate use of figurative language and the techniques of its correct interpretation. Furthermore, Aristotle ascribes to metaphor (and to various other “excellent” sayings) the function of increasing and enhancing our knowledge. Thus, according to the Stagirite, figurative language is not only an ornamental device, but it can also have a significant explanatory power. Finally, Aristotle observes that figurative expressions cause words to become ambiguous. In this context, the philosopher notices that ambiguity can enrich the language of a poet, but it can also hinder a dialectical discussion. Accordingly, Aristotle is inclined to value polysemy either positively or negatively. Importantly, however, the Stagirite is perfectly aware of the fact that in natural languages ambiguity is unavoidable. This is why Aristotle initiates a syste-matic reflection on the phenomenon of ambiguity and distinguishes its various kinds. In Aristotle, ambiguity is, then, both a problem that needs to be identified and a tool that can help in elucidating intricate philosophical issues. This unique approach to ambiguity and figurative (“enigmatic”) language enabled Aristotle to formulate invaluable intuitions that still await appropriate recognition.

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Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Arquitetura e Urbanismo

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A method called "SymbolDesign" is proposed that can be used to design user-centered interfaces for pen-based input devices. It can also extend the functionality of pointer input devices such as the traditional computer mouse or the Camera Mouse, a camera-based computer interface. Users can create their own interfaces by choosing single-stroke movement patterns that are convenient to draw with the selected input device and by mapping them to a desired set of commands. A pattern could be the trace of a moving finger detected with the Camera Mouse or a symbol drawn with an optical pen. The core of the SymbolDesign system is a dynamically created classifier, in the current implementation an artificial neural network. The architecture of the neural network automatically adjusts according to the complexity of the classification task. In experiments, subjects used the SymbolDesign method to design and test the interfaces they created, for example, to browse the web. The experiments demonstrated good recognition accuracy and responsiveness of the user interfaces. The method provided an easily-designed and easily-used computer input mechanism for people without physical limitations, and, with some modifications, has the potential to become a computer access tool for people with severe paralysis.