959 resultados para Classical tradicion
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This paper presents experimental and computational results of oxy-fuel burner operating on classical flame and lameless mode for heat release rate of 26 kW/m3. The uniqueness of the burner arises from a slight asymmetric injection of oxygen at near sonic velocities. Measurements of emperature, species, total heat flux, radiative heat flux and NOx emission were carried out inside the furnace and the flow field was computationally analyzed. The flame studies were carried out for coaxial flow of oxygen and fuel jets with similar inlet velocities. This configuration results in slow mixing between fuel and oxygen and the flame is developed at distance away from the burner and the flame is bright/white in colour. In the flameless mode a slight asymmetric injection of the high velocity oxygen jet leads to a large asymmetric recirculation pattern with the recirculation ratio of 25 and the resulting flame is weak bluish in colour with little soot and acetylene formation. The classical flame in comparison is characterised by soot and acetylene formation, higher NOx and noise generation. The distribution of temperature and heat flux in the furnace is more uniform with flameless mode than with flame mode.
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KIRCHHOFF’S theory [1] and the first-order shear deformation theory (FSDT) [2] of plates in bending are simple theories and continuously used to obtain design information. Within the classical small deformation theory of elasticity, the problem consists of determining three displacements, u, v, and w, that satisfy three equilibrium equations in the interior of the plate and three specified surface conditions. FSDT is a sixth-order theory with a provision to satisfy three edge conditions and maintains, unlike in Kirchhoff’s theory, independent linear thicknesswise distribution of tangential displacement even if the lateral deflection, w, is zero along a supported edge. However, each of the in-plane distributions of the transverse shear stresses that are of a lower order is expressed as a sum of higher-order displacement terms. Kirchhoff’s assumption of zero transverse shear strains is, however, not a limitation of the theory as a first approximation to the exact 3-D solution.
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We propose a new scheme for the use of constraints in setting up classical, Hamiltonian, relativistic, interacting particle theories. We show that it possesses both Poincaré invariance and invariance of world lines. We discuss the transition to the physical phase space and the nonrelativistic limit.
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We present relativistic, classical particle models that possess Poincaré invariance, invariant world lines, particle interaction, and separability.
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The problem of separability in recent models of classical relativistic interacting particles is examined. This physical requirement is shown to be more subtle than naive separability of all the constraints defining the system: it is adequate to be able to canonically transform the time-fixing constraints from an unseparated to a separated form when clusters emerge. Viewing separability in this way, and within a specific framework, we are led to a new no-interaction theorem which states the incompatibility of nontrivial interaction with relativistic invariance, separability, and invariant world lines for more than two particles.
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Although globular proteins are endowed with well defined three-dimensional structures, they exhibit substantial mobility within the framework of the given threedimensional structure. The different types of mobility found in proteins by and large correspond to the different levels of organisational hierarchy in protein architecture. They are of considerable structural and functional significance, and can be broadly classified into(a) thermal and conformational fluctuations, (b) segmental mobility, (c) interdomain mobility and (d) intersubunit mobility. Protein crystallographic studies has provided a wealth of information on all of them. The temperature factors derived from X-ray diffraction studies provide a measure of atomic displacements caused by thermal and conformational fluctuations. The variation of displacement along the polypeptide chain have provided functionally significant information on the flexibility of different regions of the molecule in proteins such as myoglobin, lysozyme and prealbumin. Segmental mobility often involves the movement of a region or a segment of a molecule with respect to the rest, as in the transition between the apo and the holo structures of lactate dehydrogenase. It may also involve rigidification of a disordered region of the molecule as in the activation of the zymogens of serine proteases. Transitions between the apo and the holo structures of alcohol dehydrogenase,and between the free and the sugar bound forms of hexokinase, are good examples of interdomain mobility caused by hinge-bending. The capability of different domains to move semi-independently contributes greatly to the versatility of immunoglobulin molecules. Interdomain mobility in citrate synthase appears to be more complex and its study has led to an alternative description of domain closure. The classical and the most thoroughly studied case of intersubunit mobility is that in haemoglobin. The stereochemical mechanism of the action of this allosteric protein clearly brings out the functional subtilities that could be achieved through intersubunit movements. In addition to ligand binding and activation,environmental changes also often cause structural transformations. The reversible transformation between 2 Zn insulin and 4 Zn insulin is caused by changes in the ionic strength of the medium. Adenylate Kinase provides a good example for functionally significant reversible conformational transitions induced by variation in pH. Available evidences indicate that reversible structural transformations in proteins could also be caused by changes in the aqueous environment, including those in the amount of water surrounding protein molecules.
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The present challenge in drug discovery is to synthesize new compounds efficiently in minimal time. The trend is towards carefully designed and well-characterized compound libraries because fast and effective synthesis methods easily produce thousands of new compounds. The need for rapid and reliable analysis methods is increased at the same time. Quality assessment, including the identification and purity tests, is highly important since false (negative or positive) results, for instance in tests of biological activity or determination of early-ADME parameters in vitro (the pharmacokinetic study of drug absorption, distribution, metabolism, and excretion), must be avoided. This thesis summarizes the principles of classical planar chromatographic separation combined with ultraviolet (UV) and mass spectrometric (MS) detection, and introduces powerful, rapid, easy, low-cost, and alternative tools and techniques for qualitative and quantitative analysis of small drug or drug-like molecules. High performance thin-layer chromatography (HPTLC) was introduced and evaluated for fast semi-quantitative assessment of the purity of synthesis target compounds. HPTLC methods were compared with the liquid chromatography (LC) methods. Electrospray ionization mass spectrometry (ESI MS) and atmospheric pressure matrix-assisted laser desorption/ionization MS (AP MALDI MS) were used to identify and confirm the product zones on the plate. AP MALDI MS was rapid, and easy to carry out directly on the plate without scraping. The PLC method was used to isolate target compounds from crude synthesized products and purify them for bioactivity and preliminary ADME tests. Ultra-thin-layer chromatography (UTLC) with AP MALDI MS and desorption electrospray ionization mass spectrometry (DESI MS) was introduced and studied for the first time. Because of the thinner adsorbent layer, the monolithic UTLC plate provided 10 100 times better sensitivity in MALDI analysis than did HPTLC plates. The limits of detection (LODs) down to low picomole range were demonstrated for UTLC AP MALDI and UTLC DESI MS. In a comparison of AP and vacuum MALDI MS detection for UTLC plates, desorption from the irregular surface of the plates with the combination of an external AP MALDI ion source and an ion trap instrument provided clearly less variation in mass accuracy than the vacuum MALDI time-of-flight (TOF) instrument. The performance of the two-dimensional (2D) UTLC separation with AP MALDI MS method was studied for the first time. The influence of the urine matrix on the separation and the repeatability was evaluated with benzodiazepines as model substances in human urine. The applicability of 2D UTLC AP MALDI MS was demonstrated in the detection of metabolites in an authentic urine sample.
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Formulation of quantum first passage problem is attempted in terms of a restricted Feynman path integral that simulates an absorbing barrier as in the corresponding classical case. The positivity of the resulting probability density, however, remains to be demonstrated.
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This dissertation studies the language of Latin letters that were written in Egypt and Vindolanda (in northern Britain) during the period 1st century BC 3rd century AD on papyri, ostraca, and wooden tablets. The majority of the texts is, in one way or another, connected with the Roman army. The focus of the study is on syntax and pragmatics. Besides traditional philological methods, modern syntactic theory is used as well, especially in the pragmatic analysis. The study begins with a critical survey of certain concepts that are current in the research on the Latin language, most importantly the concept of vulgar Latin , which, it is argued, seems to be used as an abstract noun for variation and change in Latin . Further, it is necessary to treat even the non-literary material primarily as written texts and not as straightforward reflections of spoken language. An examination of letter phraseology shows that there is considerable variation between the two major geographical areas of provenance. Latin letter writing in Egypt was influenced by Greek. The study highlights the importance of seeing the letters as a text type, with recurring phraseological elements appearing in the body text as well. It is argued that recognising these elements is essential for the correct analysis of the syntax. Three areas of syntax are discussed in detail: sentence connection (mainly parataxis), syntactically incoherent structures and word order (the order of the object and the verb). For certain types of sentence connection we may plausibly posit an origin in spoken Latin, but for many other linguistic phenomena attested in this material the issue of spoken Latin is anything but simple. Concerning the study of historical syntax, the letters offer information about the changing status of the accusative case. Incoherent structures may reflect contaminations in spoken language but usually the reason for them is the inability of the writer to put his thoughts into writing, especially when there is something more complicated to be expressed. Many incoherent expressions reflect the need to start the predication with a thematic constituent. Latin word order is seen as resulting from an interaction of syntactic and pragmatic factors. The preference for an order where the topic is placed sentence-initially can be seen in word order more generally as well. Furthermore, there appears a difference between Egypt and Vindolanda. The letters from Vindolanda show the order O(bject) V(erb) clearly more often than the letters from Egypt. Interestingly, this difference correlates with another, namely the use of the anaphoric pronoun is. This is an interesting observation in view of the fact that both of these are traditional Latin features, as opposed to those that foreshadow the Romance development (VO order and use of the anaphoric ille). However, it is difficult to say whether this is an indication of social or regional variation.
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This study analyses the diction of Latin building inscriptions. Despite its importance, this topic has rarely been discussed before: the most substantial contribution on the subject is a short dissertation by Klaus Gast (1965) that focuses on 100 inscriptions dating mostly from the Republican period. Marietta Horster (2001) also touched upon this theme in her thesis on imperial building inscriptions. I have collected my source material in North Africa because more Latin building inscriptions dating from the Imperial period have survived there than in any other area of the Roman Empire. By means of a thorough and independent survey, I have assembled all relevant African Latin building inscriptions datable to the Roman period (between 146 BC and AD 425), 1002 texts, into a corpus. These inscriptions are all fully edited in Appendix 1; Appendix 2 contains references to earlier editions. To facilitate search operations, both are also available in electronic form. They are downloadable from the address http://www.helsinki.fi/hum/kla/htm/jatkoopinnot.htm. Chapter one is an introduction dealing with the nature of building inscriptions as source material. Chapter two offers a statistical overview of the material. The following main section of the work falls into five chapters, each of which analyses one main part of a building inscription. An average building inscription can be divided into five parts: the starting phrase opens the inscription (a dedication to gods, for example), the subject part identifies the builder, the object part describes the constructed or repaired building, the predicate part records the building activity and the supplement part offers additional information on the project (it can specify the funding, for instance). These chapters are systematic and chronological and their purpose is to register and interpret the phrases used, to analyse reasons for their use and for their popularity among the different groups of builders. Chapter eight, which follows the main section of the work, creates a typology of building inscriptions based on their structure. It also presents the most frequently attested types of building inscriptions. The conclusion describes, on a general level, how the diction of building inscriptions developed during the period of study and how this striking development resulted from socio-economic changes that took place in Romano-African society during Antiquity. This study shows that the phraseology of building inscriptions had a clear correlation both with the type of builder and with the date of carving. Private builders tended to accentuate their participation (especially its financial side) in the project; honouring the emperor received more emphasis in the building inscriptions set up by communities; the texts produced by the army were concise. The chronological development is so clear that it enables stylistic dating. At the beginning of the imperial period the phrases were clear, concrete, formal and stereotyped but by Late Antiquity they have become vague, subjective, flexible, varied and even rhetorically or poetically coloured.
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Työ käsittelee Rooman laivaston kehitystä, toimintaa ja osallistumista laajenemispolitiikkaan, jossa Rooma kasvoi kaupunkivaltiosta Välimeren hallitsijaksi. Rooma on aikaisemmissa tutkimuksissa nähty maavaltiona vailla kiinnostusta merenkulkuun. On katsottu, että ainoa merkittävä merisota Rooman historiassa on ensimmäinen puunilaissota (264-241 eKr.) ja että siinäkin roomalaiset (jotka historioitsija Polybius kuvaa vasta-alkajiksi) menestyivät Karthagoa vastaan turvautumalla laskusiltoihin, joiden avulla he saattoivat muuttaa meritaistelun maataisteluksi. Polybiuksen kuvaukseen on aina tähän asti luotettu. On katsottu että Roomalla ei ollut laivastoa ennen ensimmäistä puunilaissotaa ja että Rooma kaikissa sodissaan panosti merisodankäyntiin mahdollisimman vähän. Tämä työ pyrkii kumoamaan nämä käsitykset. Laivasto oli osallisena ja ehdottoman välttämätön kaikissa Rooman laajenemispolitiikan käänteissä. Arkeologian tiedot osoittavat, että ennen ensimmäistä puunilaissotaa Rooma kehittyi ja siitä tuli merkittävä kaupunki nimenomaan kaupankäynnin ja ulkomaisten kontaktien seurauksena. Se ei siis ollut puhdas agraarivaltio. Roomalaisilla oli laivasto jo viimeistään 500-luvulta lähtien eKr. ja sitä käytettiin Rooman laajentaessa valtaansa Italiassa. Näin ollen ensimmäisessä puunilaissodassa läntisen Välimeren herruudesta kilpaili kaksi merivaltiota, Rooma ja Karthago. Toinen puunilaissota (218-201) tunnetaan yleensä Hannibalin tulosta Alppien yli Italiaan, mutta se oli myöskin merkittävä merisota ja karthagolaiset hävisivät sen nimenomaan merellä. Rooma osallistui kilpailuun itäisen Välimeren hallinnasta ja kukisti Makedonian ja Syyrian laivastot, jotka eivät olleet mitenkään Rooman laivaston veroisia. Kaikista Rooman vastustajista Karthagolla olisi ollut suurin mahdollisuus pysäyttää Rooman laivaston voittokulu toisessa puunilaissodassa. Laivastoa käytettiin moniin eri tarkoituksiin. Suuret meritaistelut eivät ole ainoa osoitus laivastojen mukanaolosta ja merkityksestä, vaan on myös otettava huomion sotalaivojen rakenne ja toimintaedellytykset. Sotalaivat oli rakennettu taisteluita varten ja niissä oli hyvin niukasti säilytystilaa. Niiden oli päästävä laskemaan maihin aina kun miehistö tarvitsi vettä, ruokaa ja lepoa. Laivastot saattoivat toimia vain niiden rannikoiden tuntumassa, joiden satamiin ja laskupaikkoihin niillä oli turvallinen pääsy. Roomalaiset olivat hyvin tietoisia tästä. Suuret merentakaiset sotaretket Afrikkaan, Espanjaan, Kreikkaan ja Vähän-Aasian rannikolle perustuivat kaikki siihen, että Rooman laivasto hallitsi purjehdusreittejä ja sopivia laskupaikkoja ja saattoi huolehtia joukkojen ja varusteiden kuljettamisesta kaukana taisteleville armeijoille. Samalla Rooman laivasto kävi itsenäistä sotaa merellä ja haastoi ja kukisti kaikki Välimeren merivaltiot. 130-luvulle eKr. tultaessa se oli lyönyt vihollisensa ja riisunut aseista liittolaisensa; Rooman laivasto hallitsi Välimerta yksin.
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The main aim of the study is to create a many-sided view of dancing in Roman Egypt (1st - early 4th centuries AD) and especially of the dancers who earned their living by dancing as hired performers. Even though dancers and other performers played a central part in many kinds of festivities throughout the ancient world, research on ancient professional dancers is rare and tends to rest on the ancient literature, which reflects the opinions of the elite. Documentary written sources (i.e., papyri, ostraka) the core of the present study are mentioned rather superficially, easily resulting in a stereotypical view of the dancers. This study will balance the picture of professional dancers in antiquity and of ancient dancing in a more general sense. The second aim characterizes this study as basic research: to provide a corpus of written sources from Greco-Roman Egypt on dancing and to discuss pictorial sources contemporary with the texts. The study also takes into account the theoretical discussion that centres on dancing as a nonverbal communicative mode. Dancers are seen as significant conveyors of social and cultural matters. This study shows that dancers were hired to perform especially in religious contexts, where the local associations on the village level also played an important part as the employers of the performers. These performers had a better standard of living in economic terms than the average hired worker, and dancers were better paid than other performers. In the Egyptian villages and towns, where the dancers performed and lived, the dancers do not seem to have been marginal because they were professionals or because of some ethnic or social background. However, their possible marginality may have occurred for reasons related to the practicalities of their profession (e.g., the itinerant life style). The oriental background of performers was a literary topos reflecting partly the situation in the centres of the empire, especially Rome, where many performers were of other than Roman origin. The connection of dancing, prostitution and slavery reflects the essential link between dance, body and gender: dancers are equated with such professions or socio-legal statuses where the body is the focus of attention, a commodity and a source of sensual pleasure; this dimension is clearly observable in ancient literature. According to the Egyptian documentary sources, there is no watertight evidence that professional dancers would have been engaged in prostitution and very little, if any, evidence that the disapproval of the professional dancers expressed by the ancient authors was shared by the Egyptians. From the 4th century onwards the dancers almost disappear from the documentary sources, reflecting the political and religious changes in the Mediterranean east.