1000 resultados para sound synthesis
Resumo:
Solid-state Ln-L compounds, where Ln stands for heavy trivalent lanthanides (Tb-Lu) and L is malonate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, TG-FTIR system, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The dehydration of the compounds begins at 303 K and the anhydrous compounds are stable up to 548 K. The results also provided information concerning the ligand's denticity, thermal behaviour and identification of some gaseous products evolved during the thermal decomposition of these compounds.
Resumo:
Synthesis, electronic, infrared, elemental micro analytical studies were carried on N-(benzothiazol-2-yl)trichloroethanamide [4] and N-(benzothiazol-2-yl)chloroethanamide [5]. They were also screened in vitro and in vivo for antibacterial activity. The results indicate that the compounds are very stable and that they show high antibacterial activities against both gram-positive and gram-negative bacteria tested. Both derivatives of 2-aminobenzothiazole were active against the multiresistant bacteria with IZD ranging from 9 -18 mm [5] and 9 - 20mm [4]. From the MIC results it is observed that the [5] derivative produced a better antibacterial activity than the [4] derivative. The lethal concentrations (LC50) of the compounds were also determined. Their solubilities and melting points were also determined.
Resumo:
Pure and Fe(III)-doped TiO2 suspensions were prepared by the sol gel method with the use of titanium isopropoxide (Ti(OPri)4) as precursor material. The properties of doped materials were compared to TiO2 properties based on the characterization by thermal analysis (TG-DTA and DSC), X-ray powder diffractometry and spectroscopy measurements (FTIR). Both undoped and doped TiO2 suspensions were used to coat metallic substrate as a mean to make thin-film electrodes. Thermal treatment of the precursors at 400ºC for 2 h in air resulted in the formation of nanocrystalline anatase TiO2. The thin-film electrodes were tested with respect to their photocatalytic performance for degradation of a textile dye in aqueous solution. The plain TiO2 remains as the best catalyst at the conditions used in this report.
Resumo:
A set of models in Aspen plus was built to simulate the direct synthesis process of hydrogen peroxide in a micro-reactor system. This process model can be used to carry out material balance calculation under various experimental conditions. Three thermodynamic property methods were compared by calculating gas solubility and Uniquac-RK method was finally selected for process model. Two different operation modes with corresponding operation conditions were proposed as the starting point of future experiments. Simulations for these two modes were carried out to get the information of material streams. Moreover, some hydrodynamic parameters such as gas/liquid superficial velocity, gas holdup were also calculated with improved process model. These parameters proved the proposed experimental conditions reasonable to some extent. The influence of operation conditions including temperature, pressure and circulation ratio was analyzed for the first operation mode, where pure oxygen was fed into dissolving tank and hydrogen-carbon dioxide mixture was fed into microreactor directly. The preferred operation conditions for the system are low temperature (2°C) and high pressure (30 bar) in dissolving tank. High circulation ratio might be good in the sense that more oxygen could be dissolved and fed into reactor for reactions, but meanwhile hydrodynamics of microreactor should be considered. Furthermore, more operation conditions of reactor gas/liquid feeds in both of two operation modes were proposed to provide guidance for future experiment design and corresponding hydrodynamic parameters were also calculated. Finally, safety issue was considered from thermodynamic point of view and there is no explosion danger at given experimental plan since the released reaction heat will not cause solvent vaporization inside the microchannels. The improvement of process model still needs further study based on the future experimental results.
Resumo:
The flow of information within modern information society has increased rapidly over the last decade. The major part of this information flow relies on the individual’s abilities to handle text or speech input. For the majority of us it presents no problems, but there are some individuals who would benefit from other means of conveying information, e.g. signed information flow. During the last decades the new results from various disciplines have all suggested towards the common background and processing for sign and speech and this was one of the key issues that I wanted to investigate further in this thesis. The basis of this thesis is firmly within speech research and that is why I wanted to design analogous test batteries for widely used speech perception tests for signers – to find out whether the results for signers would be the same as in speakers’ perception tests. One of the key findings within biology – and more precisely its effects on speech and communication research – is the mirror neuron system. That finding has enabled us to form new theories about evolution of communication, and it all seems to converge on the hypothesis that all communication has a common core within humans. In this thesis speech and sign are discussed as equal and analogical counterparts of communication and all research methods used in speech are modified for sign. Both speech and sign are thus investigated using similar test batteries. Furthermore, both production and perception of speech and sign are studied separately. An additional framework for studying production is given by gesture research using cry sounds. Results of cry sound research are then compared to results from children acquiring sign language. These results show that individuality manifests itself from very early on in human development. Articulation in adults, both in speech and sign, is studied from two perspectives: normal production and re-learning production when the apparatus has been changed. Normal production is studied both in speech and sign and the effects of changed articulation are studied with regards to speech. Both these studies are done by using carrier sentences. Furthermore, sign production is studied giving the informants possibility for spontaneous speech. The production data from the signing informants is also used as the basis for input in the sign synthesis stimuli used in sign perception test battery. Speech and sign perception were studied using the informants’ answers to questions using forced choice in identification and discrimination tasks. These answers were then compared across language modalities. Three different informant groups participated in the sign perception tests: native signers, sign language interpreters and Finnish adults with no knowledge of any signed language. This gave a chance to investigate which of the characteristics found in the results were due to the language per se and which were due to the changes in modality itself. As the analogous test batteries yielded similar results over different informant groups, some common threads of results could be observed. Starting from very early on in acquiring speech and sign the results were highly individual. However, the results were the same within one individual when the same test was repeated. This individuality of results represented along same patterns across different language modalities and - in some occasions - across language groups. As both modalities yield similar answers to analogous study questions, this has lead us to providing methods for basic input for sign language applications, i.e. signing avatars. This has also given us answers to questions on precision of the animation and intelligibility for the users – what are the parameters that govern intelligibility of synthesised speech or sign and how precise must the animation or synthetic speech be in order for it to be intelligible. The results also give additional support to the well-known fact that intelligibility in fact is not the same as naturalness. In some cases, as shown within the sign perception test battery design, naturalness decreases intelligibility. This also has to be taken into consideration when designing applications. All in all, results from each of the test batteries, be they for signers or speakers, yield strikingly similar patterns, which would indicate yet further support for the common core for all human communication. Thus, we can modify and deepen the phonetic framework models for human communication based on the knowledge obtained from the results of the test batteries within this thesis.
Resumo:
Denna vårdvetenskapliga studie har sökarljuset riktat mot lyssnande som något fundamentalt för människan. Studiens syfte är att utifrån forskarens traditionstillhörighet och en klart uttalad teorikärna, värdegrund, ontologisk grund samt en hermeneutisk ansats avtäcka nytt inseende om vad lyssnande är samt vad som är vårdande i lyssnande. Studiens avsikt är att bringa ontologisk klarhet, klargöra lyssnandets plats inom vårdvetenskaplig teoribildning samt bidra med bilder av det vårdande med relevans för klinisk praxis. Det hermeneutiska arbetssättet är en ständig rörelse mellan det enskilda och gemensamma. Den vårdvetenskapliga traditionens grundläggande ordning utgör siktet för kunskapssökandet samtidigt som det är gentemot den caritativa vårdteorin som nytt inseende ur historiska källor reflekteras för att lysa upp och synliggöra det evidenta och ursprungliga om lyssnande. Begreppsutredningen av lyssna som begrepp ger förståelse för begreppets historiska ursprung och dess starka band med begreppen lyss, lystra, lyda, följa, iaktta, se samt lust, begär, böjelse och glädje. Läsning och begrundan av filosoferna Bubers, Lévinas och författaren Dostojevskijs livsverk avtäcker vittnesbörd och stillbilder som tolkas för att synliggöra tolkningsantaganden om lyssnandets väsen och gestaltning. Jag har läst och begrundat texterna med öppenhet, lyhördhet och en kvardröjande hållning för att låta dem beröra, tilltala mig och framträda som något nytt. Ur de enskilda texterna avtäcks mönster av en gemensam inre ordning och en gemensam stillbild och tolkningsantaganden om lyssnande formas. När den gemensamma inre ordningen får sammanstråla med studiens vårdvetenskapliga grund synliggörs en urbild och teser om lyssnande samt det vårdande i lyssnande. Avtäckandet visar att lyssnande är en grundhållning till livet självt. Människan lyssnar till sitt innersta väsen för att tillägna sig en inre grundordning samt hörsamma sin tillhörighet i en mera allomfattande gemenskap till den skapande, den andre och det oändliga. I ljuset av kärlekens kraft och bejakandet av mänskligt lidande kan ensamhet och gemenskap sluta förbund med varandra i en mellanverklighet som bär oändlighetens och evighetens kännetecken, och som får toner av det heliga och eviga att ljuda i allt och alla i en närvaro här och nu. Lyssnande är en väsenshandling som uttalas genom en vårdande hållning att tjäna, offra och bära ansvar för den andre med medmänsklig barmhärtighet och medmänskligt medlidande. Band till den andre knyts genom den egna sårbarheten och genom att med ödmjukhet, äkthet och gästfrihet bjuda in och välkomna den andre i sin annanhet. Den vårdande gemenskapen skapar en rörelse som bär på en livsbringande kraft genom vilken människan uppnår frihet att varda, finna näring och försoning.
Resumo:
Production of biofuel via biomass gasification followed by Fischer Tropsch synthesis is of considerable interest because of the high quality of fuels produced which do not contain sulphur and are free of carbon dioxide. The purpose of this Master’s thesis is to study feasibility production of biofuels integrated with Fischer Tropsch process using Aspen Plus simulation. The simulation results were used to size process equipment and carry out an economic evaluation. The results show that lowering the reactor temperature from 1000 oC - 850 oC and raising the water gas shift temperature from 500 oC - 600 oC can improve overall gas efficiency, which in turn leads to better production of ultra clean syngas for the Fischer Tropsch synthetic reactor. Similarly, the Fischer Tropsch offgas is converted into a gas turbine for power production, and finally biodiesel is produced as fuels for transportation.
Resumo:
Dysfunction of the dopaminergic system in brain is involved in several pathological conditions such as Parkinson’s disease and depression. 2β-Carbomethoxy-3β-(4-[18F] fluorophenyl)tropane ([18F]CFT) and 6-[18F]fluoro-L-dopa ([18F]FDOPA) are tracers for imaging the dopaminergic function with positron emission tomography (PET). Peripheral uptake of [18F]FDOPA is also used in the localization and diagnosis of neuroendocrine tumors. [18F]FDOPA and [18F]CFT can be synthesized by electrophilic fluorodestannylation. However, the specific radioactivity (SA) in the electrophilic fluorination is low with traditional synthetic methods. In this study, [18F]FDOPA and [18F]CFT were synthesized using post-target-produced [18F]F2 as an electrophilic fluorination agent. With this method, tracers are produced with sufficient SA for neuroreceptor studies. Specific aims in this study were to replace Freon-11 in the production of [18F]FDOPA due to the ozone depleting properties of this solvent, to determine pharmacological specificity and selectivity of [18F]CFT with respect to monoamine transporters, and to compare the ability of these tracers to reflect the degree of nigral neuronal loss in rats in which the dopaminergic system in the brain had been unilaterally destroyed by 6- OHDA. Post-target-produced [18F]F2 was successfully used in the production of [18F]FDOPA and [18F]CFT. The SA achieved was substantially higher than in previous synthetic methods. Deuterated compounds, CD2Cl2, CDCl3 and C3D6O, were found to be suitable solvents for replacing Freon-11. Both [18F]FDOPA and [18F]CFT demonstrated nigrostriatal dopaminergic hypofunction and correlated with the number of nigral dopaminergic neurons in the 6-OHDA lesioned rat. However, the dopamine transporter (DAT) tracer [18F]CFT was more sensitive than the dopamine synthesis tracer [18F]FDOPA in detecting these defects because of the higher non-specific uptake of [18F]FDOPA. [18F]CFT can also be used for imaging the norepinephrine transporter (NET) because of the specific uptake into the locus coeruleus. The observation that [18F]CFT exhibits specific uptake in the pancreas warrants further studies in humans with respect to potential utility in pancreatic imaging
Resumo:
Percarboxylic acids are commonly used as disinfection and bleaching agents in textile, paper, and fine chemical industries. All of these applications are based on the oxidative potential of these compounds. In spite of high interest in these chemicals, they are unstable and explosive chemicals, which increase the risk of synthesis processes and transportation. Therefore, the safety criteria in the production process should be considered. Microreactors represent a technology that efficiently utilizes safety advantages resulting from small scale. Therefore, microreactor technology was used in the synthesis of peracetic acid and performic acid. These percarboxylic acids were produced at different temperatures, residence times and catalyst i.e. sulfuric acid concentrations. Both synthesis reactions seemed to be rather fast because with performic acid equilibrium was reached in 4 min at 313 K and with peracetic acid in 10 min at 343 K. In addition, the experimental results were used to study the kinetics of the formation of performic acid and peracetic acid. The advantages of the microreactors in this study were the efficient temperature control even in very exothermic reaction and good mixing due to the short diffusion distances. Therefore, reaction rates were determined with high accuracy. Three different models were considered in order to estimate the kinetic parameters such as reaction rate constants and activation energies. From these three models, the laminar flow model with radial velocity distribution gave most precise parameters. However, sulfuric acid creates many drawbacks in this synthesis process. Therefore, a ´´greener´´ way to use heterogeneous catalyst in the synthesis of performic acid in microreactor was studied. The cation exchange resin, Dowex 50 Wx8, presented very high activity and a long life time in this reaction. In the presence of this catalyst, the equilibrium was reached in 120 second at 313 K which indicates a rather fast reaction. In addition, the safety advantages of microreactors were investigated in this study. Four different conventional methods were used. Production of peracetic acid was used as a test case, and the safety of one conventional batch process was compared with an on-site continuous microprocess. It was found that the conventional methods for the analysis of process safety might not be reliable and adequate for radically novel technology, such as microreactors. This is understandable because the conventional methods are partly based on experience, which is very limited in connection with totally novel technology. Therefore, one checklist-based method was developed to study the safety of intensified and novel processes at the early stage of process development. The checklist was formulated using the concept of layers of protection for a chemical process. The traditional and three intensified processes of hydrogen peroxide synthesis were selected as test cases. With these real cases, it was shown that several positive and negative effects on safety can be detected in process intensification. The general claim that safety is always improved by process intensification was questioned.
Resumo:
In this thesis, biocatalysis is defined as the science of using enzymes as catalysts in organic synthesis. Environmental aspects and the continuously expanding repertoire of available enzymes have firmly established biocatalysis as a prominent means of chemo-, regio- and stereoselective synthesis. Yet, no single methodology can solve all the challenges faced by a synthetic chemist. Therefore, the knowledge and the skills to combine different synthetic methods are relevant. Lipases are highly useful enzymes in organic synthesis. In this thesis, an effort is being made to form a coherent picture of when and how can lipases be incorporated into nonenzymatic synthesis. This is attempted both in the literature review and in the discussion of the results presented in the original publications contained in the thesis. In addition to lipases, oxynitrilases were also used in the work. The experimental part of the thesis comprises of the results reported in four peer-reviewed publications and one manuscript. Selected amines, amino acids and sugar-derived cyanohydrins or their acylated derivatives were each prepared in enantio- or diastereomerically enriched form. Where applicable, attempts were made to combine the enzymatic reactions to other synthetic steps either by the application of completely separate sequential reactions with isolated intermediates (kinetic and functional kinetic resolution of amines), simultaneously occurring reactions without intermediate isolation (dynamic kinetic resolution of amino acid esters) or sequential reactions but without isolating the intermediates (hydrocyanation of sugar aldehydes with subsequent diastereoresolution). In all cases, lipase-catalyzed acylation was the key step by which stereoselectivity was achieved. Lipase from Burkholderia cepacia was a highly selective enzyme with each substrate category, but careful selection of the acyl donor and the solvent was important as well.
Resumo:
-
Resumo:
Trough computed tomography (CT), it is possible to evaluate lymph nodes in detail and to detect changes in these structures earlier than with radiographs and ultrasound. Lack of information in the veterinary literature directed the focus of this report to normal aspects of the axillary and mediastinal lymph nodes of adult dogs on CT imaging. A CT scan of 15 normal adult male and female Rottweilers was done. To define them as clinically sound, anamnesis, physical examination, complete blood count, renal and hepatic biochemistry, ECG, and thoracic radiographs were performed. After the intravenous injection of hydrosoluble ionic iodine contrast medium contiguous 10mm in thickness thoracic transverse images were obtained with an axial scanner. In the obtained images mediastinal and axillary lymph nodes were sought and when found measured in their smallest diameter and their attenuation was compared to musculature. Mean and standard deviation of: age, weight, body length and the smallest diameter of the axillary and mediastinal lymph nodes were determined. Mean and standard deviation of parameters: age 3.87±2.03 years, weight 41.13±5.12, and body length 89.61±2.63cm. Axillary lymph nodes were seen in 60% of the animals, mean of the smallest diameter was 3.58mm with a standard deviation of 2.02 and a minimum value of 1mm and a maximum value of 7mm. From 13 observed lymph nodes 61.53% were hypopodense when compared with musculature, and 30.77% were isodense. Mediastinal lymph nodes were identified in 73.33% of the dogs; mean measure of the smallest diameter was 4.71mm with a standard deviation of 2.61mm and a minimum value of 1mm, and a maximum value of 8mm. From 14 observed lymph nodes 85.71% were isodense when compared with musculature and 14.28% were hypodense. The results show that it is possible to visualize axillary and mediastinal lymph nodes in adult clinically sound Rottweilers with CT using a slice thickness and interval of 10mm. The smallest diameter of the axillary and mediastinal lymph nodes not surpassed 7mm and 8mm respectively. Their attenuations were equal or smaller than that of musculature in the post contrast scan.
Resumo:
Tämä pro gradu -tutkielma käsittelee äänitehosteiden kääntämistä sarjakuvissa. Tutkimus perustuu seitsemän eri sarjakuvan äänitehosteiden ja niiden suomennoksien vertailuun. Tutkitut tehosteet on kerätty yhdeksi korpukseksi kolmesta Aku Ankka -tarinasta, Tenavat- ja Lassi ja Leevi -stripeistä sekä Batman- ja Vartijat sarjakuvaromaaneista.Sarjakuvat edustavat osittain eri genrejä, jotta saadaan tietoa erityyppisten sarjakuvien mahdollisesti erilaisista käännöskonventioista. Aku Ankka -sarjakuvien määrää on painotettu, jotta olisi mahdollista saada tarkempi kuva yhdestä yksittäisestä sarjakuvasta, jossa oletetaan äänitehosteiden pääsääntöisesti olevan käännettyjä. Äänitehosteita ja äänitehostekäännöksiä tutkitaan kahdesta eri näkökulmasta.Tutkielman ensimmäisessä osassa tarkastellaan äänitehosteissa käytettyjä käännösstrategioita ja etsitään seikkoja, jotka vaikuttavat eri käännösstrategioiden käyttöön ja tehosteiden kääntämiseen tai kääntämättä jättämiseen. Kaindlin (1999) esittelemää sarjakuvien käännösstrategiajaottelua verrataan Celottin (2008) kuvaan upotettuihin teksteihin soveltuviin käännösstrategioihin. Näiden pohjalta muokattua jaottelua käytetään käännösten analysointiin. Korpuksessa yleisimmin käytetyt käännösstrategiat olivat alkutekstin siirtäminen sellaisenaan käännökseen ja kääntäminen suomalaiseksi ilmaisuksi. Jonkin verran esiintyi myös tehosteiden poistoja, siirtämisiä ja jopa lisäyksiä. Paljon muutoksia tapahtui myös esimerkiksi tehosteiden ulkoasussa. Sarjakuvan tyyppi vaikutti oletusten mukaisesti käännösstrategioihin; selvimmin aikuisille suunnatuissa sarjakuvissa paljon tehosteita oli jätetty kääntämättä, kun taas erityisesti Aku Ankoissa tehosteidenkin käännöksiin oli kiinnitetty huomiota. Myös tehosteen sijainti puhekuplassa, kuplan ulkopuolella tai kuvaan upotettuna vaikutti siihen, oliko tehoste käännetty vai ei. Tutkimuksen toisessa osassa äänitehosteet jaotellaan semanttisen sisältönsä mukaan seuraaviin ryhmiin: iskut, rikkoutuminen, räjähdykset ja ampuminen, hankaus, ilmavirta, ruoka ja nesteet, pitkäkestoiset äänet sekä äänenkorkeudeltaan selvästi korkeat ja matalat äänet. Jaotteluperusteina toimivat äänten kuvaamat tapahtumat, äänen syntymiseen osallistuvat materiaalit tai äänitehosteiden itsensä ominaisuudet. Ryhmien esimerkeistä löytyi yhteisiä piirteitä, jotka selittynevät samanlaisten äänten samanlaisella äännesymboliikalla tai samankaltaisilla onomatopoeettisilla piirteillä.