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Greule, Albrecht. "Das festlandkeltische Hydronym *Langvros: Rekonstruktion und Integration." Gesellschaft für Namenkunde e.V, 2016. https://ul.qucosa.de/id/qucosa%3A16333.
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The name of the river Lambro/Lambrus near Milano (Italy/Roman province Gallia-Transpadana) will be reconstructed as indoeuropean *h1lṇgwhró-s ‘quick’. Compared with other geographic names it will be supposed, that Lambrus is a celtic relict name. The problem is, in which way celtic labiovelars, e.g. /gw/, are integrated in the post-celtic languages.
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Drápelová, Zuzana. "Marketingový audit IMI Hydronic Engineering pro český trh." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-202053.
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The main objective of this thesis is to execute a marketing audit of IMI Hydronic Engineering at the Czech market in order to identify problem areas and opportunities, define key performance indicators (KPI) and follow recommended procedures to improve marketing performance of this company and increase the efficiency of the company as a whole. Marketing audit is a comprehensive analysis of the company and its surroundings, which does not contain only simple analysis of the current situation of the company but also the draft measure. Marketing audit in this thesis is carried out based on the methodology described in the theoretical part and consists of the analyses of six interrelated parts. The first part of the audit (audit of marketing environment) analyzes the external environment of IMI Hydronic Engineering realized through PESTLE analysis and Porter's five forces analysis. The following five sections are focusing on internal environmental audit of this company. These parts of the audit are: audit of marketing strategy, audit of marketing, audit of marketing systems, audit of marketing productivity and audit of marketing functions. The results are summarized in complex SWOT analysis. Recommendations, proposals for amendments, strategies, objectives and KPIs are listed in the conclusion.
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Rogers, Dan. "Modelling, control and scheduling of hydronic domestic heating systems." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6980/.
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Cole, Charles Randal. "Electron stimulated desorption of hydronium ions from chromium oxide surfaces." W&M ScholarWorks, 2005. https://scholarworks.wm.edu/etd/1539623480.
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The mass spectral peak observed at 19 amu in residual gas analyzers at very high (<10-6 Torr) and ultrahigh vacuum (<10 -9 Torr) has often been attributed to fluorine. Using Fourier Transform Mass Spectrometry, the hydronium ion, H3O+, has been fully resolved from F+ and its correlation to water vapor concentration was determined to be linear as expected for a gas phase process. The comparison of the mass 19 signals for a conventional quadrupole mass spectrometer and a Fourier transform mass spectrometer on the same vacuum chamber indicated hydronium was the source of mass 19.;The partial pressures of H2O in the very high vacuum range and higher suggest there is sufficient H2O density for the hydronium ions to form through ion-molecule interactions because hydronium formation was found to directly correlate with the H2O partial pressure. However, in a QMS at UHV, formation of H3O+ appears to occur principally by electron stimulated desorption (ESD). Introducing hydrogen into the system from 1 Langmuir exposure to saturation (1 x 10-6 Torr for 8 hours) increased the H3O + ESD yield detected by the QMS by as much as a factor of 10. The initial hydronium ESD cross section from a hydrogen saturated grid was estimated to be sigma ∼ 1 x 10-19, cm2.;TOF-SIMS sputter yields from the stainless steel grid of a quadrupole mass spectrometer also showed small signals of H3O+, as well as its constituents (H+, O+ and OH) and a small amount of fluorine as F-, but no F+ or F+ complexes (HF+, etc.). Using x-ray photoelectron spectroscopy, a small amount (0.4%) of fluorine was found in the surface of stainless steel. Electron bombardment reduces the fluorine bound in surface complexes, but not metal halides found below the surface. However, heating the sample eliminated the F 1s signal entirely, indicating that fluorine is not likely to be the source of mass 19 in residual gas analysis. Also, changes in the spectral shoulders on the O 1s and Cr 2P3/2 peaks show that hydrogen dosing stainless steel and chromium increases the amount of hydroxides at the surface, while heating and electron bombardment reduce them.
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Győrffy, Erzsébet. "Linguistic layers of Old Hungarian hydronyms." Gesellschaft für Namenkunde e.V, 2010. https://ul.qucosa.de/id/qucosa%3A12628.
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When analysing the etymological layers of Hungarian river names, it becomes soon clear that loan names make up a much larger group than in the group of settlement names, for instance. This fact can be due to the phenomenon that in the case of hydronyms, name-giving and name-usage is driven mainly by communicative needs, while other (e. g. socio-cultural or political) factors only rarely influence name-giving. In my paper, it was my aim to provide an etymological typology of Hungarian hydronyms from the Árpád-era (896 –1350). It seems to be justified to choose the Hungarian hydronyms of the Árpád-era as the corpus of my investigation, for the country was strongly multilingual and multiethnic in this period of time (Hungarian, Slavic, German, Turkish), which also has an effect on the system of water names. The survey of the linguistic layers of river names shows that largely the same semantic content appears in river names originating from different languages. The semantic types appearing in river names belong to the so-called panchronistic feature of the hydronym system, in other words, they show signs of universal human thinking.
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Győrffy, Erzsébet. "Linguistic layers of Old Hungarian hydronyms." Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-146287.
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When analysing the etymological layers of Hungarian river names, it becomes soon clear that loan names make up a much larger group than in the group of settlement names, for instance. This fact can be due to the phenomenon that in the case of hydronyms, name-giving and name-usage is driven mainly by communicative needs, while other (e. g. socio-cultural or political) factors only rarely influence name-giving. In my paper, it was my aim to provide an etymological typology of Hungarian hydronyms from the Árpád-era (896 –1350). It seems to be justified to choose the Hungarian hydronyms of the Árpád-era as the corpus of my investigation, for the country was strongly multilingual and multiethnic in this period of time (Hungarian, Slavic, German, Turkish), which also has an effect on the system of water names. The survey of the linguistic layers of river names shows that largely the same semantic content appears in river names originating from different languages. The semantic types appearing in river names belong to the so-called panchronistic feature of the hydronym system, in other words, they show signs of universal human thinking.
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Embaye, Mebrahtu. "Enhancement of panel radiator based hydronic central heating system using flow pulsation." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6856/.
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Enhancing the heat output of the hydronic central heating system in buildings can play a major role in reducing energy consumption and CO2 emission. The main aim of this PhD research is to investigate the effect of pulsed flow input on the energy consumption of panel radiators in hydronic central heating systems and the user indoor comfort defined by ASHRAE standard 55 and EN ISO 7730. The research covers thermal performance of panel radiator and the indoor comfort. The work was performed using dynamic control modelling, CFD and experimental testing to prove the concept. Results from the mathematical and CFD modelling of the hydronic radiator with pulsed flow using various frequencies and amplitudes showed that 20% to 27% of energy saving can be achieved compared to the constant flow while maintaining the same radiator target surface temperature of 50oC as recommended by the BS EN442. The indoor comfort results were also achieved as recommended by international standards including CO2 concentration at 1000PPM±50PPM, relative humidity at 50±9%, comfort temperature at 20±1.6oC, air velocity of below 0.15m/s and draught risk parameters of less than 15%. The numerical results agreed well with experimental results with maximum deviation of radiator temperature output of ±4.1%, indoor temperature ±2.83% and energy saving of ±1.7%. The energy saved due to the pulsed flow is attributed to the enhancement of the radiator heat transfer performance that leads to higher heat output at lower average mass flow rate of the hot water.
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Foley, Jeffrey Arthur. "Hydronium ion and water interactions with SiOSi, SiOAl, and AlOAl tetrahedral linkages." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/104320.
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Coelho, Helena Isabel Soares Dinis. "Microphytobenthos vs Hydrobia: trophic coupling in estuarine environment." Doctoral thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3632.
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Doutoramento em BiologiaOs estuários são ambientes complexos, biologicamente diversos e muito importantes no que respeita à produtividade primária. As zonas intertidais destes ecossistemas são ocupadas por organismos que possuem uma elevada capacidade de sobrevivência e adaptação face às variadas e rápidas alterações nos factores ambientais (tais como temperatura, salinidade, conteúdo hídrico, etc.). As cadeias tróficas com origem no ecossistema estuarino bentónico são essencialmente herbívoras, regulando o fluxo de energia desde o fundo sedimentar e através do ecossistema. Nas áreas estuarinas intertidais a produção primária é essencialmente suportada pelo microfitobentos (MPB). Estas comunidades de microalgas bênticas constituem uma importante fonte de matéria orgânica e são por si só a principal fonte alimentar para as populações de Hydrobia. Neste contexto, a interacção MPB - Hydrobia é um modelo-chave na investigação da cadeia trófica estuarina de origem bentónica, actuando como um importante canal de transporte de energia para os níveis tróficos superiores, especialmente se considerarmos que Hydrobia é uma importante presa para peixes, aves e caranguejos. O presente estudo tem por objectivos gerais: i) a investigação do controlo ambiental (particularmente da luz e do teor em água do sedimento) e endógeno na migração vertical do MPB e ii) a identificação e potencial utilização de marcadores tróficos (pigmentos e ácidos gordos) úteis à investigação da interacção MPB – Hydrobia em laboratório e em condições naturais, considerando a existência de uma elevada plasticidade trófica por parte da Hydrobia e a elevada densidade populacional que estes organismos podem apresentar. A primeira fase de investigação resultou na comparação do papel dos estímulos ambientais e do controlo endógeno nos padrões de comportamento migratório vertical do microfitobentos, demonstrando a existência de um controlo essencialmente endógeno na formação e desintegração do biofilme superficial. A regulação e manutenção da biomassa à superfície do sedimento são claramente controladas pela variação dos factores ambientais, em especial da luz, cuja presença é essencial à formação total do biofilme microalgal à superfície do sedimento intertidal. Foi proposta uma nova abordagem metodológica com vista à estimativa nãodestrutiva do teor de água de sedimentos intertidais vasosos , possibilitando o estudo da influência da acção do vento no conteúdo hídrico dos sedimentos e o consequente impacto da dessecação na comunidade microfitobêntica. Observou-se que a dessecação provoca efeitos limitantes não só na biomassa superficial mas também na actividade fotossintética dos biofilmes microfitobênticos, conduzindo à diminuição da produtividade primária. No que respeita à dinâmica trófica da interacção MPB - Hydrobia foi estabelecido o uso do pigmento feoforbide a, quantificado nas partículas fecais da fauna, como marcador trófico que permite estimar a quantidade de biomassa de microalgas (clorofila a) incorporada pelos organismos animais.Para tal foi investigada e comprovada a existência de uma relação significativa entre a concentração de feopigmentos excretados e a concentração de clorofila a ingerida. Estes estudos foram desenvolvidos numa primeira fase à escala diária, considerando os efeitos dos ciclos sazonais, dia-noite e maré, e depois com a validação em condições naturais, numa escala mensal. A taxa de ingestão média de indivíduos de H. ulvae varia ao longo do dia, com o máximo em torno dos períodos diurnos de maré baixa, o que pode estar relacionado com a disponibilidade de MPB. As taxas de ingestão (TI) de H. ulvae variam ainda em função da estação do ano (TI verão > TI primavera) e em função da densidade de indivíduos (> densidade, < ingestão). Verificou-se um efeito negativo na concentração de clorofila disponível após herbívoria independentemente da densidade de indivíduos. Finalmente, a comparação dos perfis de ácidos gordos de H. ulvae provenientes de diferentes habitats com os perfis de potenciais fontes alimentares permitiu demonstrar que os ácidos gordos são ferramentas úteis na identificação do habitat ocupado por estes organismos. No entanto, apesar da ocupação de diferentes habitats e da integração de múltiplas fontes de produção primária na sua dieta foram sempre observados significativos níveis de ácidos gordos específicos de microalgas (em particular diatomáceas), reforçando o papel importante das comunidades de microalgas bênticas na dieta das populações de H. ulvae.
Estuaries are biologically diverse and form complex environments, which play an important role on the global primary productivity of aquatic environments. Intertidal areas of estuaries are inhabited by organisms with a strikingly capability to survive and to be adapted to frequent and fast changes in several environmental factors (such as temperature, salinity, water content, etc.). Grazing food chains are common in intertidal mudflats regulating the flow of nutrients and energy from the bottom throughout the estuarine ecosystem. Within intertidal estuarine areas the primary production was predominantly supported by microphytobenthos (MPB). These benthic microalgae assemblages are an important source of organic matter and are a main food source for Hydrobia populations. The MPB - Hydrobia interaction is a key model for the estuarine grazing food chain, acting as a significantly channel of energy to higher trophic levels, since Hydrobia is an important prey item for fish, birds and crabs. The present work addressed: i) the environmental (namely light and sediment water content) and the endogenous control of the vertical migration by microphytobenthos, and ii) the identification and the potential use of trophic markers (pigments and fatty acids) to establish this relationship under laboratory and natural conditions, considering that H. ulvae showed significant trophic plasticity and that mud snails could reach extremely high densities. The role of exogenous cues and endogenous control of the patterns of vertical migratory behavior of intertidal MPB biofilms were compared, showing that the formation and disintegration of the biofilm is endogenously-controlled. The regulation and maintenance of the microalgal biomass at the sediment surface is dependent on the variation of environmental factors, namely light, which is essential for the full formation of the MPB biofilm. A new methodological approach was proposed to estimate the water content of muddy intertidal sediments, enabling the study of the influence of wind on the hydric level of the sediment and the consequent impact of desiccation on the MPB biomass. This investigation showed that desiccation might be responsible to cause important limiting effects on biomass and photosynthetic activity of intertidal MPB biofilms, reducing the primary productivity. Regarding the trophic dynamics of the interaction MPB - Hydrobia, it was established the use of the pigment pheophorbide a, present on Hydrobia ulvae faecal pellets, as a trophic marker to estimate the amount of microalgal biomass incorporated, as chlorophyll a, by benthic macrofauna. A significant relationship between egested pheopigments and ingested chlorophyll a was investigated and validated. These studies were firstly developed on a daily scale, considering the effects of seasonal, tidal and day-night cycles, followed by a validation under natural conditions, on a monthly scale. The mean ingestion rate of H. ulvae individuals varied along the day, with the maximum around the diurnal low tide periods, which may be related with MPB availability. H. ulvae mean ingestion rate (IR) also varies seasonally (IR summer > IR spring) and depending on mud snails density (> density, < ingestion). There was a negative effect on chlorophyll concentration available after grazing, independently of H. ulvae density. Finally, the comparison of fatty acid profiles of mud snails from different habitats with the ones from potential food sources allowed identifying fatty acids as a useful tool to indicate H. ulvae habitat. Although the occupation of different habitats and the integration of multiple primary food sources on mud snails diet, significant inputs of fatty acids specific of microalgae (namely diatoms) were always found, which reinforce the important role of MPB on the diet of H. ulvae populations.
FCT; FSE - SFRH/BD/23720/2005
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Loupová, Iveta. "Komunikační kampaň na vybraný produkt společnosti TA Hydronics." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-165354.
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The aim of this diploma work is to create a marketing campaign of TA Hydronics product operating in the B2B market. The theoretical part will deal with the first characteristic of the concept of communication, followed by analysis of the current situation of the company, marketing and communication mix, which is diffused by new trends in communication. Next section will follow the implementation and monitoring phase. There is a characteristic of TA Hydronics at the practical part. A further part will focus on the marketing campaign proposal, with the transition to marketing situational analysis, including analysis of the internal and external environment.There is a control stage at the end of this work.
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Djordjevic, Nikola. "Efficiency of the Hydronic System used for the Space-Heating of Passive Envelopes." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19402.
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The aim of this thesis is to determine the efficiency of the hydronic heating system implemented in building with passive envelopes. Thermal losses and energy consumption of the pump are relative values for determining the efficiency.The first step towards this aim is to provide theoretical background for better understanding of the hydronic system. The advantages of this system are also presented.Good knowledge of hydronic systems, first of all, modes of transport of the work fluid and heat distribution into the space, makes a good basis for the next step- designing the system.Once the system is designed, it is possible to create mathematical model. This model together with the input values given enables creation and a running of a simulation program.In the end the results from the simulation are obtained for a typical Norwegian house which satisfies recommendation for the passive house concept.The analyses of our results shows, in spite of the heat losses from the pipes and pump energy consumption, it is feasible to fulfill the prescribed limitations regarding the Passive house energy consumption. Unfortunately, the heat losses values are not negligible and it will eventually disturb thermal comfort.The method derived in this report as well as the simulation program presented can serve as a starting point for future investigation of an assortment of hydronic systems variations. One of the logical choices is certainly a system with insulated pipes. Such system could provide the key advantage of hydronic systems compared to other heating systems. In that way they could present themselves as the best heating solution for future buildings with passive envelopes.
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King, Jacob. "Analytical tools for toponymy : their application to Scottish hydronymy." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3020.
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It has long been observed that there is a correlation between the physical qualities of a watercourse and the linguistic qualities of its name; for instance, of two river-names, one having the linguistic quality of river as its generic element, and one having burn, one would expect the river to be the longer of the two. Until now, a phenomenon such as this had never been formally quantified. The primary focus of this thesis is to create, within a Scottish context, a methodology for elucidating the relationship between various qualities of hydronyms and the qualities of the watercourses they represent. The area of study includes every catchment area which falls into the sea from the River Forth, round the east coast of Scotland, up to and including the Spey; also included is the east side of the River Leven / Loch Lomond catchment area. The linguistic strata investigated are: Early Celtic, P-Celtic, Gaelic and Scots. In the first half of the introduction scholarly approaches to toponymy are discussed, in a Scottish and hydronymic context, from the inception of toponymy as a discipline up to the present day; the capabilities and limitations of these approaches are taken into consideration. In the second half the approaches taken in this thesis are outlined. The second chapter explains and justifies in more detail the methodology and calculus used in this thesis. The subsequent chapters examine the following linguistic components of a hydronym: generic elements, linguistic strata, semantics and phonological overlay. In each of these chapters the methodology is harnessed as an analytical tool to generate new findings for hydronymic research. The conclusion consists of a summary of the findings and a review of the performance of the calculus. It emerges that these analytical tools are of use to the field of toponymy in two ways. Firstly, they formalise and challenge previously unquantified statements made in the field of toponymy. Secondly, they elucidate hitherto unnoticed phenomena. It is suggested that in the future this methodology be applied to other datasets (particularly hill-names) and to other regions in Scotland and the world at large.
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Brembilla, Christian. "Modelling and simulation of building components : thermal interaction between multilayer wall and hydronic radiator." Licentiate thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-121201.
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Background and Scope: The scope of this thesis is to investigate the thermal behaviour of building components as hydronic radiator and multilayer walls subjected to dynamic conditions. The modelling and simulation of these building components provide information on how these components thermally interact among each other. The thermal interaction is fundamental to know how the energy is used in buildings. In particular, the thermal energy used in rooms can be expressed as the efficiencies for emission in a space heating system. This thesis analyzes the efficiencies for emission of a space heating system equipped with hydronic radiator for Swedish buildings by providing a comprehensive and detailed approach on this topic. Methodology: The methods used in this thesis are: experiment, modelling of multilayer wall and hydronic radiator, the dynamic simulation of the building and the efficiencies for emission of a space heating system. Here, the experiment, known as step response test, shows the heating up process of a hydronic radiator. The observation of the qualitative measurements suggests the most suitable technique of modelling the radiator known as transient modelling with multiple storage elements. The multilayer wall has been discretized both in space and time variable with a Finite Difference Method. Dynamic simulation of the building provides the efficiencies for emission of a space heating system. Findings: The experimental results show how the radiator performs the charging phase. The performance of the transient model is compared with lumped steady state models in terms of temperature of exhaust flow and total heat emitted. Results of the dynamic simulation show how buildings located in a Northern climate use the energy in a better way than Southern climates in Sweden. Heavy active thermal mass provides higher efficiencies for emission than light thermal mass. Radiators with connection pipes located on the same side react faster at the thermodynamic changing of the mass flow rate by providing higher efficiencies for emission than radiators with connection pipes located on the opposite side. Conclusion and Outlook: This thesis increases the knowledge about the modelling and simulation of hydronic radiators and multilayer walls. More research is needed on this topic to encompass modelling details of building components often ignored. The modelling and simulation of building components are the key to understand how building components thermally interact with each other. The thermal interaction among building components is a fundamental parameter for the assessment of efficiencies of emission of the space heating system. In the near future, the concept of efficiencies of emission can be implemented in National Building Code, therefore, this study provides guidelines on how to assess these efficiencies.Advisors: Ronny Östin and Mohsen Soleimanni Mohseni, Department of Applied Physics and Electronics, Umeå University
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Stosiek, Christoph. "Struktur und Eigenschaften von nanoskopischen Metall(hydroxid)fluorid-Aluminiumoxid-Kompositen." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16162.
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Durch die Verwendung der fluorolytischen Sol-Gel Synthese ist es möglich, röntgenamorphe bzw. partiell nanokristalline Metallhydroxidfluoride und Metallfluoride zu erhalten. Diese Verbindungen unterscheiden sich in ihren Eigenschaften stark von „klassisch“ hergestellten, kristallinen Metall(hydroxid)fluoriden. In der vorliegenden Promotionsarbeit wurden deshalb in vier aufeinander folgenden Kapiteln sowohl die Synthese und Charakterisierung von Aluminium– und Magnesium(hydroxid)fluoriden beschrieben als auch die Auswirkung dieser Verbindungen auf das Phasentransformationsverhalten von böhmitischen Xerogelen zu Korund sowie ihre Wirksamkeit als Sinterhilfsmittel bei der Korundkeramikherstellung untersucht.The application of the fluorolytic sol-gel method with aqueous hydrofluoric acid enables the synthesis of X-ray amorphous or rather partially nanocrystalline metal hydroxide fluorides and metal fluorides. These compounds strongly differ in their characteristics from “classically” manufactured, crystalline metal hydroxide fluorides. In the present dissertation both, the synthesis and characterisation of aluminium and magnesium hydroxide fluorides were described and the effect of these compounds on the phase transformation behaviour from pseudoboehmites to corundum was examined as well as their effectiveness as sintering aid during the corundum ceramics production.
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Fahy, Eoin. "Polyketide derived metabolites from the marine hydroid Garveia annulata." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27071.
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The marine hydroid Garveia annulata is a small, brightly colored coelenterate whose crude methanol extracts exhibit potent antibacterial and antifungal activity. The compounds responsible for this biological activity were purified and characterised as a series of related 1-[4H]-anthracenone derivatives. Twenty one metabolites have been isolated and their structures were elucidated by using a combination of spectral analysis, chemical interconversions, synthesis and single crystal X-ray diffraction analysis.
The structure of garveatin A (77), the major metabolite, was determined via a series of NMR experiments and by an X-ray diffraction analysis of its enol triacetate 87. Garveatins B (88), C (93) and D (96) share a common carbon skeleton with 77.
The garvin family represents a different polyketide folding pattern as seen in garvin A (124) and garvin B (126.) which contain an n-propyl group and a delta lactone functionality, respectively. Both the garveatins and the garvins contain oxidized analogs in the form of 2-hydroxy derivatives, 9,10 quinones and C2,2' dimers. NMR analysis and optical rotation experiments indicate that the C2 position of the 2-hydroxy compounds is racemic.
Garvalones A (137) and B (141) represent the corresponding 2-(3-oxobutyl) derivatives of garvins A and B respectively. They occur as pairs of C2 epimers. Their structures were confirmed by spectral comparison with 2-(3-oxobutyl) garveatin A (140) which was synthesised from 77.
Annulins A (144) and B (148) have degraded anthracene skeletons and they appear to be products of garveatin B metabolism.
All four families of G. annulata secondary metabolites appear to be produced by straightforward polyketide biogenesis. Different folding patterns of a putative nonaketide precursor account for all the structures elaborated. These polyketides represent the first examples of this type of metabolism in coelenterates.Science, Faculty of
Chemistry, Department of
Graduate
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Barikan, Chirin. "Hydronic Pavement Systems for Sustainable Winter Road Maintenance in Sweden : A Study of Hamnbacken in Visby." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254668.
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In countries with harsh winter climates extensive winter road maintenance is necessary to achieve traffic accessibility and road safety. These measures have high economic and environmental costs as snow free roads and winter road maintenance in Sweden today is achieved by a combination of mechanical snow clearance and the spreading of salt to prevent ice formation. The salt ends up in the roadside environment and has negative effects on groundwater and vegetation. An alternative to traditional winter road maintenance to obtain non-skid winter roads is the use of hydronic pavement(HP) systems. Existing HP systems in Sweden are powered by district heating which limits the application to urban locations. The goal is to utilize renewable energy sources such as geoenergy which can be used in both rural and urban locations. This thesis suggests Hamnbacken in Visby as a pilot project for a full-scale application of the proposed HP system using surface water source heat.The weather related road surface conditions on Hamnbacken, and the potential of a renewable energysource have been examined in this study and the proposed location has been found favourable for a HP system.Länder med övervägande kallt vinterklimat är halkbekämpning en nödvändighet för trafikens framkomlighet och säkerhet. Åtgärderna som vidtas för att få snö- och isfria vägar är kostsamma samt har en hög miljöpåverkan, ett vedertagligt exempel är plogning och saltning. Saltet hamnar i slutändan inom vägens omgivande områden och har en negativ påverkan på grundvatten och vegetation. En alternativ lösning till traditionell halkbekämpning är uppvärmda vägar för att uppnå ett halkfritt vinterväglag. Befintliga väguppvärmningssystem i Sverige försörjs av fjärrvärme vilket är en begräsning då tillgången till fjärrvärme finns i anslutning till tätorter. Målet är att utnyttja förnybara energikällor såsom geoenergi som är tillgänglig både i tätorter och på landsbygden. Det här examensarbetet undersöker Hamnbacken i Visby som ett pilotprojekt för en fullskalig implementering av väguppvärmningssystem där sjövärme används som energikälla. Denna studie har undersökt väderrelaterade vägförhållanden på Hamnbacken samt potentialen för användning av sjövärme. Den föreslagna platsens förutsättningar har visat sig vara gynnsamma i detta avseende.
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Domingues, Filipa Marisa Orêncio. "Hydrobia ulvae: 15 years of imposex monitoring in Ria de Aveiro." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/9642.
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Mestrado - Biologia AplicadaCompostos de Tributilestanho (TBT) são biocidas com um largo espectro de ação, utilizados em inúmeras aplicações industriais. Nos anos 60, estes compostos foram utilizados como agente ativo em tintas anti-vegetativas de barcos, bóias, plataformas e outras estruturas submersas, para prevenção de bioincustração. Quando libertados nos ecossistemas aquáticos a sua toxicidade provoca diversos efeitos biológicos em espécies não-alvo. Um desses efeitos é o desenvolvimento de caracteres sexuais masculinos sobre o trato reprodutivo de fêmeas de gastrópodes prosobrânquios, um fenómeno apelidado por imposex. A expressão do imposex é um efeito direto da exposição in situ ao TBT e é utilizado como biomarcador da sua poluição. As várias e generalizadas descrições de elevados níveis de poluição por TBT levaram à implementação de legislações extremamente restritivas da utilização destes compostos. Atualmente, e desde 2008, estão interditas a aplicação e circulação de compostos de TBT em embarcações e portos de estados membros da União Europeia, bem como em embarcações de países que assinaram a Convenção Internacional para a Convenção de Sistemas Antivegetativos Prejudiciais em Navios (Convençao AFS). Contudo, e apesar de estar reportado uma redução na poluição ambiental por TBT após estas medidas, estes compostos podem estar a ser utilizados em países em desenvolvimento, o que requer uma monitorização constante. Além disso, mesmo onde os inputs não são permitidos, a monitorização de sedimentos é requerida, pois este compartimento constitui um reservatório de TBT, acumulado durante as décadas de uso intenso. Várias espécies bioindicadoras podem ser utilizadas para avaliação do imposex e monitorizar a poluição por TBT. Estas devem ser selecionadas cuidadosamente, dependendo da sua abundancia e distribuição na área de estudo e também do compartimento que está a ser monitorizado. De forma a avaliar o estado da poluição por TBT e a sua evolução temporal durante a última década na Ria de Aveiro (Noroeste de Portugal), em especial nos sedimentos, foi utilizado o gastrópode Hydrobia ulvae como espécie bioindicadora. Os 10 locais de amostragem selecionados foram monitorizados em 1998, e em 2003/2004/2007, sendo revisitados em 2012. Os níveis de imposex foram avaliados e os compostos organoestânicos (OTs) foram quantificados nos sedimentos. Ocorreu uma diminuição geral das concentrações de TBT em sedimentos entre 1998 e 2012. No entanto, os níveis de imposex na H. ulvae não diminuíram durante o mesmo período. Em vez disso, houve um aumento global da percentagem de fêmeas afetadas pelo imposex (variou entre 76-100%) e uma manutenção geral do índice da sequência do vaso deferente (VDSI; oscilou entre 0,93 e 1,17). Assim, existe outra razão para além da exposição ao TBT que causa a manutenção da intensidade do imposex e a prevalência deste fenômeno, que aumenta ao longo deste sistema estuarino. Na verdade, a percentagem de indíviduos parasitadas também aumentou ao longo da área de estudo entre 2003 e 2012. Aliás, todas as fêmeas infestadas exibiam imposex e nenhuma fêmea não afetada pelo imposex estava parasitada. Assim, o fenómeno do imposex pode ser uma consequência do aumento deste parasitismo em populações Hydrobia ulvae na Ria de Aveiro, facto corroborado pelos d ados recolhidos no estudo presente. Através de análises estatísticas foi demostrado um efeito positivo da presença de parasitas nos índices VDSI (P = 1,4x10-3) e FPL (tamanho do pénis feminino; P = 8,4x10-5), ao contrário do efeito das concentrações de TBT nos sedimentos nos mesmos parâmetros (P = 0,62 e P = 0,99, respectivamente). No entanto, mais estudos são necessários para confirmar esta hipótese de que pode restringir o uso desta espécie como bioindicador da poluição por TBT em populações parasitadas.
Tributyltin (TBT) compounds are broad spectrum biocides with multiple industrial applications. They have been used as active ingredients in anti-fouling paints formulations, at a global scale since the 60s, and applied in vessels hulls, buoys, platforms and other submerged structures to prevent bioincrustation. Once released into the aquatic environment, and given its proven toxicity, several adverse biological effects are induced on non-target species. One of these effects is the development of male sexual characters onto the reproductive track of prosobranch gastropods females, a phenomenon termed imposex. Imposex expression is a direct effect of TBT exposure in situ, and has been widely used as a biomarker for TBT pollution. The numerous and generalized descriptions of high levels of TBT pollution and also its the negative effects led to the implementation of extremely restrictive legislation on these compounds usage. Presently, and since 2008, TBT compounds application and circulation are banned from EU member states fleets, and respective ports, and from ships flying flags of countries signatories of the International Convention for the Convention on the Control of Harmful Antifouling Systems on Ships (AFS Convention). However, and despite reports of TBT environmental pollution reduction after such measures, these compounds can still be used in third countries, requiring continued monitoring. Furthermore, even where inputs are now prohibited, sediment monitoring is required since this compartment constitutes a reservoir of TBT accumulated during decades of intense use. Several bioindicator species can be used for imposex assessment and TBT pollution monitoring. Therefore, the bioindicator should be carefully selected depending on the abundance and distribution in the study area, and also on the compartment being monitored. In order to evaluate the TBT pollution current status and its temporal evolution in the last fourteen years in Ria de Aveiro (NW Portugal), namely its persistence in sediments, the gastropod Hydrobia ulvae was selected as a bioindicator. The 10 sampling sites previously surveyed in 1998 and in 2003/2004/2007 were revisited in 2012. Imposex levels were assessed and the organotins (OTs) quantified in sediments. There was a general decrease of TBT concentrations in sediments between 1998 and 2012. Even so, H. ulvae imposex levels did not decrease in the same period. Instead, there was a global increase in the percentage of females affected by imposex (varied between 76 and 100%) and a general maintenance of the vas deferens sequence index (VDSI; from 0.93 to 1.17). It is therefore obvious that other reason than TBT exposure is causing imposex intensity maintenance and the phenomenon increased prevalence through this estuarine system. Actually, the percentage of parasitized specimens also increased throughout the study area between 2003 and 2012. Moreover, all infected females exhibited imposex and none imposex-affected female was parasitized. Thus, the imposex phenomenon might be a consequence of this increased parasitism in populations of Hydrobia ulvae in the Ria de Aveiro, a fact corroborated by the data collected in this study. Through statistical analyzes, it was demonstrated a positive effect of the presence of parasitic organisms in VDSI (P = 1.4x10-3) and FPL (female penis length; P = 8.4x10-5), contrasting with the effect of TBT concentration in sediments, in the same imposex parameters (P = 0.62 and P = 0.99, respectively). However, further studies are needed to confirm this hypothesis that can constrain the use of this species as a bioindicator of TBT pollution in parasitized populations.
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Heffington, Samuel N. "Development and analysis of a vibration-induced droplet atomization module for high heat flux cooling applications." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/16758.
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Schoonover, Kevin George. "An experimental and numerical investigation of evaporating water sprays injected into flowing superheated steam." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17935.
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Morse, Valerie Jane. "The regulation and origin of bioluminescence in the hydroid obelia." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/53880/.
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There are many questions associated with the understanding of the origin and regulation of bioluminescence. A key question underlying this thesis was why coelenterazine evolved as the most common marine luciferin. Another problem addressed was the coelenterazine source of the bioluminescent hydroid Obelia, which is unknown. Coelenterazine is an integral part of Obelia’s photoprotein, triggered by Ca2+. The thesis also investigated the uncertainty over how Ca2+ enters Obelia’s photocytes. Obelia is considered to have four species, but they have been misidentified. Green fluorescent protein (GFP) acts as a fluor in Obelia producing green light. The selective advantage of this green bioluminescence requires confirmation. Results showed that Obelia geniculata cultures rapidly lost their bioluminescence, indicating Obelia requires a dietary supply of coelenterazine. Adding coelenterazine to Obelia briefly restored its bioluminescence. Levels of obelin dropped in Obelia geniculata cultures. Obelia longissima had a lower level of coelenterazine and bioluminescence than Obelia geniculata. Coelenterazine was detected in species living on Obelia and, three non luminous species of copepod. A range of species were identified in zooplankton, as possible coelenterazine sources. Ratios of obelin to apoobelin changed in older colonies. The problem of misidentification of Obelia species was solved by utilising the fluorescent patterns of Obelia’s photocytes. GFP was recorded for the first time in the hydrotheca and tentacles of Obelia dichotoma. Fluorescence maxima for Obelia geniculata and Obelia dichotoma iv were different. GFP in Obelia was found to photobleach far slower than GFP in EGFP. This supports the hypothesis that Obelia has a molecular mechanism which protects its GFP from photobleaching. Light emission from Obelia geniculata was different from Obelia longissima. This suggests that the mode of entry of Ca2+ into the photocytes of these two species is different. To investigate the exact pathway by which initial stimulation of Obelia causes Ca2+ to enter the photocytes, experiments were conducted using K+ channel blockers. The potassium ion channel blockers tetraethyl ammonium chloride and 4-aminopyridine both produced a bioluminescent response in Obelia geniculata. This suggested that the pathway included K+channels. In a polar solvent coelenterazine produced low chemiluminescence, which increased with increasing luciferin concentration. Human albumin and BSA increased this effect. This supported the solvent cage hypothesis that bioluminescent proteins originally evolved as primitive oxygenase enzymes.
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Hurley, James Thomas. "Analysis of steam and hydronic compartment heating systems aboard U.S. Coast Guard 140 foot WTGB class cutters." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA315405.
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Becker, Moritz [Verfasser]. "Thermochemische Energiespeicherung mit Calcium-Oxid und -Hydroxid: Entwicklung eines Reaktorkonzeptes / Moritz Becker." München : Verlag Dr. Hut, 2021. http://d-nb.info/1232847658/34.
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Nilsson-Böös, Viktor. "Differenstrycksregulatorer : En studie om hydronisk reglering av radiatorsystem med hjälp av differenstrycksregulatorer." Thesis, Mittuniversitetet, Avdelningen för kemiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-28642.
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The purpose of this work was to investigate in which types of systems where use of differential pressure controllers is possible. And to analyze which success factors using of differential pressure controllers can provide. The work was done with the help of a literature review and discussions with energy consultants at the company FVB Sweden AB. This work does not assume any specific case, but treat scenarios that could occur in reality. There are three main scenarios created to demonstrate the function and importance of differential pressure controllers in a heating system. These scenarios treat cases where one pump is supplying both homes and businesses, when buildings will be built in stages and when the pump supplies a group of properties comprising both one-pipe and two-pipe systems. The study has shown that in all three scenarios imbalance in flow will occur in the heating system, this is reported under the chapter result in the report. In cases where the problem is imbalance of flows, the problem can be solved by installing only a static control valve on the outgoing return line from the property. Financial calculations carried out in this work. These calculations are showing what the additional cost will be for a differential pressure controller, compared to a static control valve. Calculations that show the cost savings that can be made when installing a differential pressure regulator has also been done. The conclusion of this work is that in all three scenarios presented in the results section, a differential pressure controller should be installed to provide the heating system with a balanced flow. Although it is a more expensive alternative, cost savings can be achieved, which justifies the installation of a differential pressure controller in the heating system.Syftet med detta arbete var att undersöka i vilka typer av systemlösningar som användning av differenstrycksregulatorer är möjlig, samt att undersöka vilka framgångsfaktorer som användning av differenstryckregulatorer kan ge. Arbetet har genomförts med hjälp av en litteraturstudie och samtal med energikonsulter på företaget FVB Sverige AB. Detta arbete utgår inte från något specifikt fall, utan behandlar scenarion som skulle kunna uppstå i verkligheten. Det är främst tre scenarion som skapats för att kunna visa differenstryckregulatorers funktion och betydelse i ett värmesystem. Dessa scenarion är då en (1) pump försörjer både bostäder och verksamheter, när fastigheter skall byggas i etapper samt när en (1) pump försörjer en grupp byggnader som har både ett- och tvårörssystem. Studien har visat att det kommer i samtliga tre scenarion uppstå obalans i värmesystemet, detta redovisas under kapitlet resultat i rapporten. I de fall där obalans i flöden finns kan problemet lösas med att endast installera en statisk stamventil på utgående returledning från fastigheten. Ekonomiska beräkningar har även genomförts i detta arbete. Dessa beräkningar visar på vad merkostnaden blir för en differenstrycksregulator, jämfört med endast en stamventil. Det har även genomförts beräkningar som visar vilka kostnadsbesparningar som kan göras vid installation av en differenstryckregulator. Sammanfattningsvis blir slutsatsen av detta arbete att i samtliga tre scenarion som redovisas i resultatkapitlet, bör en differenstryckregulator installeras för att undvika obalans i systemen. Trots att det är ett dyrare alternativ kan kostnadsbesparingar åstadkommas, vilket motiverar en installation av en differenstryckregulator i värmesystemet.
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Tunzi, Michele. "Optimising the operation of hydronic heating systems in existing buildings for connection to low temperature district heating networks." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38724/.
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This thesis presents a new method developed to adapt existing hydronic systems in buildings to take advantage of low temperature district heating (LTDH). The work carried out was performed by extensive use of buildings’ energy modelling, validated through recorded data. Two different case studies were investigated and the dynamic heat demand profiles, simulated for each building, were used to evaluate plate radiators connected to single and double string heating loops. The method considered an optimisation procedure, based on supply and return temperatures, to obtain the required logarithmic mean temperature difference (LMTD). The results of the analysis are presented as the average reduction of LMTD over the heating season compared to the base case design conditions. The developed strategy was applied to a Danish single family house from the 1930s. Firstly it was hypothesised a heating system based on double string loop. Two scenarios were investigated based on the assumption of a likely cost reduction in the end users energy bills of 1% per each 1◦C reduction of return and average supply and return temperatures. The results showed possible discounts of 14% and 16% respectively, due to more efficient operation of the radiators. For the case of single loop system, the investigated scenario assumed a cost reduction in the end users energy bill of 1% per each 1◦C lower reduction of average supply and return temperature. Although low return temperatures could not be achieved, the implementation of the method illustrates how to efficiently operate these systems and for the given scenario a possible discount of 5% was quantified. The method was also applied to a UK small scale district heating (DH) network. The analysis began by assessing the buildings of the Estate having double string plate radiator systems. Assuming a likely cost reduction in the end users energy bills of 1% per each 1◦C reduction of return temperature, the optimisation led to obtain a possible discount in the end users energy bills of 14% with a possible yearly average return temperature of 41◦C, compared to the present 55◦C. Moreover, few improvements in the operation of the heat network were proposed. It was assumed to operate the buildings with underfloor heating systems (UFH) with average supply and return temperatures of 40/30◦C, whereas the ones with plate radiators with the optimised temperatures of 81/41◦C. The results shown that an overall average return temperature of 35.6◦C can be achieved operating the heat network as suggested. This corresponds to a decrease in the average return temperature of 18.6◦C compared to the present condition and to a reduction of 10% in the distribution heat losses. Finally, the lower average return temperature achievable would guarantee a better condensation of the flue gases, improving the overall efficiency of the biomass boiler. This was quantified as a possible reduction of fuel consumption of 9% compared to present conditions.
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Brownlow, Robert John. "Ecological and genetic studies on selected populations of the mudsnail Hydrobia ulvae (Pennant)." Thesis, Aberystwyth University, 2008. http://hdl.handle.net/2160/d6fb77e0-6215-486b-ae9b-64e7ac07c782.
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Gordillo, Ricardo Sebastián. "Cálculo de costos de productos terminados de Hydrom Oleodinámica SRL." Bachelor's thesis, Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Escuela de Ingeniería Industrial, 2016. http://hdl.handle.net/11086/4961.
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Proyecto Integrador (II)--FCEFN-UNC, 2016Presenta a Hydrom Oleodinámica SRL, empresa dedicada a la fabricación y comercialización de productos hidráulicos para maquinarias agrícolas principalmente pero también ganó lugar en maquinarias para vialidad y para otros trabajos especiales. Necesita un sistema que pueda utilizar para determinar los costos de todos sus productos para ello se diseña y plantea un sistema de costos base que le sirva a la compañía como punto de partida
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Blomqvist, Stefan. "A System Perspective on Energy End-Use Measures in a District Heated Region : Renovation of Buildings and Hydronic Pavement Systems." Licentiate thesis, Linköpings universitet, Energisystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-157082.
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A district heating and cooling (DHC) system can be a viable piece of the puzzle in the efforts of reducing the greenhouse gas (GHG) emissions. Especially if the DHC system include combined heat and power (CHP) plants which enable electricity production from renewable resources. This is set forth in national energy targets and sustainable development goals (SDGs), adopted by the United Nations in 2015. Moreover, improved energy efficiency and energy savings are important factors in fulfilling the national targets of decreased energy intensity as well as reducing the use of fossil fuels. The aim of this thesis is to analyze the impacts of two energy end-use measures in a DHC network and their consequences on the efforts towards sustainable development. The end-use measures studied are (1) renovation of a multifamily building stock and (2) the use of a hydronic pavement system (HPS) including analysis of different control strategies. The end-use measures are assessed in terms of energy use and efficiency, use of renewable and fossil resources, and local and global GHG emissions. Lastly, it is analyzed how the results relate to national energy targets and SDGs. By using simulation and optimization models, several scenarios of end-use measures are analyzed in the two studies. In the first study, six scenarios are analyzed, as the renovation packages include measures on the envelope, ventilation and conversion from district heating to ground source heat pump. In the second study three scenarios are analyzed, where the HPS are operated all-time at a temperature below 4°C or are shut down at temperatures below -10°C or at temperatures below -5°C. The results of the study regarding the renovation of a multifamily building stock indicate a future reduction in heat demand. All scenarios show energy savings of the studied building, which ranged from 11% to 56%. All scenarios show a reduction in local GHG emissions, as well as reduced fossil fuel use. Although the largest reduction was found in the use of renewable resources. From a global perspective on GHG emissions, the scenarios with district heating out-performed measures with heat pump solutions in the studied system. Moreover, the study point to positive impacts on the efforts towards SDGs. To mitigate the reduced heat demand from the renovation of the building stock, an HPS may be used. The results show mostly renewable resources were used for the HPS. The use of HPS was found to generate a positive impact on global GHG emissions. A control strategy that shuts down the HPS at temperatures below -10°C would result in 10% energy saving and would maintain acceptable performance of the HPS. Furthermore, it would reduce the use of fossil fuel and reduce local GHG emissions by 25%. Moreover, an HPS may contribute to SDGs. It is concluded that energy end-use measures of renovating a multifamily building stock are vital in the work towards an improved energy intensity. However, these measures result in a decreased demand for heat in the DHC network. This can then lead to reduced electricity production from renewable resources in the CHP plants, which in turn have a negative impact on the global GHG emissions. By finding new applications, like HPS, the infrastructure of DHC networks could be utilized efficiently and serve as one piece of the puzzle that is the efforts towards sustainable development.Ett fjärrvärme- och fjärrkylenätverk kan vara en viktig del i arbetet att minska växthusgasutsläppen. Speciellt då ett fjärrvärme- och fjärrkylenätverk nyttjar kraftvärme, vilket möjliggör elproduktion från förnybara resurser. Detta efterfrågas i de nationella energimålen och i de globala målen för hållbar utveckling, även kallade Agenda 2030, som antogs av Förenta Nationerna 2015. Dessutom är förbättrad energieffektivitet och energibesparing viktiga faktorer för att nå de nationella energimålen för minskad energiintensitet. Syftet med denna avhandling är att analysera effekterna av två användningsåtgärder i ett fjärrvärme- och fjärrkylenätverk, samt dess konsekvenser för en hållbar utveckling. De åtgärder som undersöks är (1) renovering av ett flerbostadshusbestånd och (2) användningen av ett markvärmesystem. Användningsåtgärderna analyseras utifrån energianvändning och energibesparing, användning av förnybara och fossila resurser, samt lokala och globala växthusgasutsläpp. Slutligen analyseras hur resultaten relaterar till nationella energimålen och de globala målen för hållbar utveckling. Genom att använda simulerings- och optimeringsmodeller analyseras flera scenarier av användningsåtgärder i de två studierna. I den första studien analyseras sex scenarier, där renoveringsåtgärderna innehåller klimatskals- och ventilationsåtgärder, samt ett byte av värmesystem från fjärrvärme till värmepump. I den andra studien analyseras tre scenarier. Ett då markvärmesystemet drivs kontinuerligt vid en utomhustemperatur under 4° C, samt då systemet även stängs av eller försätts i viloläge vid utomhustemperaturer under -10°C respektive -5°C. Resultaten från den först studien pekar på ett minskat värmebehov i framtiden. Alla scenarierna innebar energibesparingar i den studerade byggnaden, som varierade från 11% till 56%. Alla scenarier uppvisade en minskning av lokala växthusgasutsläpp, samt minskning av fossil bränsleanvändning. Dock ses den största minskningen i användandet av förnybara resurser. I ett globalt perspektiv på växthusgasutsläpp, så presterar värmelösningar med fjärrvärme bättre än de med värmepump i de studerade systemen. Studien uppvisar positiva effekter på de nationella målen, samt de globala målen för hållbar utveckling. För att möta den minskade värmebehovet kan ett markvärmesystem nyttjas. Resultaten visar att främst förnybara resurser används. Användningen av markvärme har en positiv inverkan på globala växthusgasutsläpp och en kontrollstrategi som försätter markvärmesystemet i vila vid temperaturer under -10°C kan resultera i 10% energibesparing samtidigt som en acceptabel prestanda bibehålls. Detta minskar den fossila bränsleanvändningen, samt de lokala växthusgasutsläppen med 25%. Ett markvärmesystem kan bidra i arbetet med de nationella målen, samt de globala målen för en hållbar utveckling. Slutsatsen är att renovering av ett bestånd av flerbostadshus ska genomföras i arbetet för en minskad energiintensitet. Dessa åtgärder leder emellertid till en minskad efterfrågan på värme. Detta kan minska elproduktion från förnybara resurser i kraftvärmeanläggningarna, vilket i sin tur har en negativ inverkan på de globala växthusgasutsläppen. Genom att hitta nya applikationer, som markvärme, kan infrastrukturen i fjärrvärme- och fjärrkylenätverk nyttjas effektivt fortsättningsvis och fungera som en bit i pusslet för en hållbar utveckling.
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Ferguson, MacNeill A. D. "The ecology of digenean parasites infecting Hydrobia ulvae (Pennant, 1777), and their functional importance within the interidal community." Thesis, University of Aberdeen, 2010. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202575.
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Aim: This series of studies assessed the influence that digenean parasites exert on a host population beyond the initial cost of infection. It aimed to address the discrepancy between the exclusion of parasites from most ecological studies, and their functional importance within the wider free-living community. It also assessed methodologies that utilise the diversity of the parasite community as well as the phenotypic effects of parasitism, as potential tools for ecology and palaeoecology. Results: From 2004-2007, in excess of 53,000 snails were dissected during the course of these studies. Making it one of the most detailed parasitological studies undertaken on a single host parasite interaction in this field. Community studies - Parasite diversity was found to be influenced by local scale abiotic, as well as large scale environmental patterns. Parasite diversity correlates with the distribution of definitive avian hosts, which in turn correlates with intertidal benthic communities. These correlations provide an effective methodology for monitoring ecosystem health. Behavioural studies - A critical assessment of parasite mediated behavioural change revealed the indirect cost of gigantism in the host population to be a side effect, and that differences in behaviours were often a result of size rather than infection. Growth/Morphometric studies - Gigantism was revealed as both infection and environment driven. Finally, morphometric analysis revealed conchiometric markers that provide tools for reconstructing past environments and infection prevalence. Main conclusions: The functional importance of digenean parasitism within the intermediate host snail Hydrobia ulvae, extends far beyond the individual. Digeneans directly and indirectly manipulate the host population, in turn affecting wider community structure. Environmental, abiotic and biotic factors can leave observable imprints on the infected and uninfected host population. Such markers can provide tools and methodologies for furthering our understanding of both extinct and extant host-parasite populations.
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Palm, Sindy. "Simultan kvantifiering av metylmalonsyra och total homocystein : En kombinationsmetod baserad på hydrofil interaktion vätskekromatografi och elektrospray jonisationsmasspektrometri." Thesis, Umeå universitet, Biomedicinsk laboratorievetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-58642.
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Strain, Lois Catherine. "An investigation of the trematode parasites in the mud snail Hydrobia ulvae from sites of ornithological importance." Thesis, University of Ulster, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243628.
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Gupta, Abhishek. "Experimental and theoretical analysis of single-phase convective heat transfer in channel with resistive heater and thermoelectric modules for hydronic cooling and heating device." Cincinnati, Ohio : University of Cincinnati, 2008. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1227203525.
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Thesis (M.S.)--University of Cincinnati, 2008.Advisor: Dr. Michael Kazmierczak PhD (Advisor), Dr. Milind A. Jog PhD (Committee Member), Dr. Sang Y. Son PhD (Committee Member), Title from electronic thesis title page (viewed Feb. 9, 2009). Includes abstract. Keywords: Peltier cooling; developing turbulent flow; internal forced convection; discrete heat flux. Includes bibliographical references.
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Gupta, Abhishek. "Experimental and theoretical analysis of single-phase convective heat transfer in channel with resistive heater and thermoelectric modules for hydronic cooling and heating device." Cincinnati, Ohio : University of Cincinnati, 2009. http://www.ohiolink.edu/etd/view.cgi?acc_num=ucin1236202446.
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Thesis (M.S.)--University of Cincinnati, 2009.Advisors: Dr. Michael Kazmierczak PhD (Committee Chair), Dr. Milind A. Jog PhD (Committee Member), Dr. Sang Y. Son PhD (Committee Member). Title from electronic thesis title page (viewed April 26, 2009). Includes abstract. Keywords: Peltier cooling; developing internal turbulent forced convection; heat pump and coefficient-of-performance. Includes bibliographical references.
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Krishnamoorthy, Sreenidhi. "Experimental Testing and Mathematical Modeling of a Thermoelectric Based Hydronic Cooling and Heating Device with Transient Charging of Sensible Thermal Energy Storage Water Tank." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227299540.
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Henry, L. "Vertical zonation and seasonality of the intertidal hydroid Dynamena pumila in the Passamaquoddy Bay region, New Brunswick." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/MQ49784.pdf.
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Mangin, Katrina Leslie. "Community effects of the invasion of a new intertidal hydroid, Samuraia tabularasa, in the Gulf of California." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185440.
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In 1984, a previously unreported species of hydroid, Samuraia tabularasa Mangin, 1991, appeared in the rocky intertidal zone of the northern Gulf of California, Mexico. Samuraia tabularasa, whose common name is the samurai hydroid, is a new genus and species in the athecate family Hydrocorynidae, class Hydrozoa, phylum Cnidaria. A key character that refers this species to a new genus is its mode of sexual reproduction by eumedusoids. Additionally, Samuraia tabularasa is able to withstand extreme desiccation in the intertidal zone, an evolutionary novelty for hydrozoans. Since its appearance, the samurai hydroid has had a dramatic effect on the community by causing the death of barnacles (Chthamalus anisopoma), the dominant occupier of space in this system, and thereby increasing the amount of primary substrate available for use by other species. Each hydroid colony is surrounded by an elliptical clearing approximately 2.5 cm in diameter that is kept clear of adult barnacles by causing the death of all newly settled barnacles that settle within reach of its tentacles. The clearings are maintained free of barnacles for sufficient time to allow for the growth of crustose algae (Ralfsia sp., and others) and subsequent grazing by limpets (Collisella strongiana) that live in the clearings. The addition of the samurai hydroid thus has led to an increase in local abundance of these two native species. This study shows that communities can be very resilient to the changes caused by the addition of a new species. Not only was there "room" for the samurai hydroid, but its activity promoted local species diversity by increasing habitat complexity. Hydroid mortality has exceeded recruitment from 1985-1990. This population decline, along with a 60% decrease in the average area of a hydroid clearing, may be associated with the hydroid's status as a recent invader and suggests that it is no longer favored in this region.
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Chen, Qiang. "Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2451.
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Following an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied.
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Serra, Simone [Verfasser]. "Untersuchungen zur Wirksamkeit des Eisen(III)hydroxid-Polymaltose-Komplexes zur Behandlung der Eisenmangelanämie bei Kindern und Jugendlichen / Simone Serra." Ulm : Universität Ulm. Medizinische Fakultät, 2014. http://d-nb.info/1054401616/34.
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Brumbaugh, Daniel Robert. "The evolution of modular adaptation : experimental studies of dispersal and growth in the marine colonial hydroid, Aglaophenia struthionides /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/5233.
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Rogers, Donna-Maria. "Adaptive variation in trematode parasite lifecycles : strategies adopted by microphallid trematodes using the mud snail Hydrobia ulvae as an intermediate host." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342343.
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House, Emily. "Refinement of PTR-MS methodology and application to the measurement of (O)VOCs from cattle slurry." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3854.
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Oxygenated volatile organic compounds ((O)VOCs) contribute to ozone formation, affect the oxidising capacity of the troposphere and are sources of growth, and in some cases formation, of aerosols. It is therefore important to identify and quantify sources of (O)VOCs in the troposphere. In the late 1990s a unique technique for quantification of organic trace gas species, proton transfer reaction mass spectrometry (PTR-MS) was developed. PTR-MS potentially offers rapid response and high sensitivity without the need for sample pre-concentration. Concentrations can be derived from the PTR-MS either by calibration or can be calculated from measured ion count rates and kinetic considerations. In this work, the methodology of PTR-MS application is critically assessed. The uncertainties and inaccuracies associated with each parameter employed in the calculation of concentrations are reviewed. This includes a critical appraisal of models for the calculation of the collisional rate constant currently applied in the field of PTR-MS. The use of a model to account for the effects of the electric field, available in the literature but not previously applied to the PTR-MS, is advocated. Collisional rate constants employing each of the models discussed have been calculated for the reactions of H3O+ with over 400 molecules for PTR-MS. In PTR-MS it cannot be assumed that the product ion occurs only at the protonated non-dissociated mass. Few product distributions obtained from PTR-MS are cited in the literature, and even then the reaction chamber conditions (pressure, temperature and electric field strength) are not always specified. A large volume of product distributions for trace gases with H3O+ in select ion flow tube mass spectrometry (SIFT) exists in the literature and is reviewed. In SIFT, no electric field is applied to the reaction chamber and the extent and even nature of fragmentation can differ in PTR-MS. In addition to the application of an electric field, the energy in the reaction chamber can be increased by increasing the temperature or by variation of the reagent ion. In this work, the increase in energy via the three methods is approximated to enable a comparison of product distributions. The review of product distributions in PTR-MS, select ion flow drift tube mass spectrometry (SIFDT), variable temperature select ion flow tube mass spectrometry (VT-SIFT), SIFT, proton transfer reaction time of flight mass spectrometry (PTR-TOF-MS), proton transfer reaction ion trap mass spectrometry (PTR-ITMS) and electron ionisation mass spectrometry (EI-MS) is used alongside thermodynamic considerations to collate a list of potential contributors to a range of mass to charge ratios (m/z) in the PTR-MS. The need for further measurements of product distributions as a function of temperature, pressure and electric field strength for a wider range of (O)VOCs is highlighted. This enables dissociation to be better used as a tool for compound identification rather than being considered a hindrance. The collation of likely product distributions is applied to identify possible contributors to m/z observed during PTR-MS measurements of emission from cattle slurry. Field measurements were made during fertilisation of a grassland site south of Edinburgh in 2004 and 2005 and in laboratory-based measurements in 2006. Contextual reasoning, previous measurements and isotope ratios are used to narrow the list of possible contributors. Large concentrations of m/z cautiously identified as alcohols followed by a latter peak in carboxylic acids were observed during laboratory measurements. Increases in the corresponding m/z were also observed during the fertilisations. Other tentatively identified compounds emitted included phenol, methyl phenol, trimethylamine, and various sulphur containing compounds.
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Kunovjánek, Miroslav. "Studium vodivosti PVA membrán, obsahujících alkalické hydroxidy." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-234580.
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Thesis deals with study of separators and membranes, suitable for using in alkali electrochemical applications like fuel cells or electrolysis. As basic material for membranes production is used polyvinylalkohol (PVA). Various methods of PVA cross linking are introduced in the thesis. PVA membranes are also doped by various types of additives to improve the attributes of the membranes like mechanical stability and or conductivity. The aim of the work is verification of parameters of membranes, doped by alkali hydroxides KOH, NaOH and LiOH at various temperatures. These hydroxides are added to the membrane especially for increasing of membrane conductivity.
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Haubois, Anne-Gaëlle. "Dynamique des transferts trophiques entre le microphytobenthos et le gastéropode déposivore Hydrobia ulvae (Pennant) sur une vasière intertidale de la Baie de Marennes-Oléron." La Rochelle, 2003. http://www.theses.fr/2003LAROS108.
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Dans l'objectif d'analyser la dynamique du flux trophique entre le microphytobenthos et le gastéropode Hydrobia ulvae nous avons caractérisé la dynamique et la structure des compartiments étudiés, puis quantifié expérimentalement l'effet de ces facteurs, ainsi que celui des principales variables environnementales, sur le taux d'ingestion de H. Ulvae. La biomasse microphytobenthique oscille entre 40 et 150 mg Chl a m-2 à l'échelle saisonnière. La communauté microalgale se caractérise par la dominance de petites espèces. L'étude de la dynamique de population de H. Ulvae a montré l'influence de mouvements d'individus sur la structure locale de la population. Le taux d'ingestion de H. Ulvae varie principalement sous l'influence de la concentration en Chl a et de la taille des individus. La réponse des juvéniles et des adultes aux variations de Chl a se caractérise par une augmentation puissance du taux d'ingestion. L'ensemble de ces données a permis une estimation du flux trophiqueThe goal of my Ph. D. Was to characterize the spatio-temporal variation of the trophic transfer between microphytobenthos and the gastropod Hydrobia ulvae. I therefore investigated structure and dynamics of the two compartments and quantified experimentally the effect of demographic and environmental variables on the individual ingestion rate of H. Ulvae. Microphytobenthic biomass varied between 40 and 150 mg Chl a. M-2 and the diatom assemblage was dominated by small-sized species. The study of H. Ulvae population dynamics showed that the population structure is strongly influenced by large-scale movements of individuals. Individual ingestion rate of H. Ulvae is mainly controlled by the chlorophyll a concentration in the sediment and individual size. The functional response of H. Ulvae, juveniles and adults over a wide range of Chl a concentration is characterized by an increase of the ingestion rate according to a power law. Finally, all results were used to estimate the trophic flux
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Golden, Daniel Lee. "Simulation and comparison of vapor-compression driven, liquid- and air-coupled cooling systems." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37297.
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Industrial and military vehicles, including trucks, tanks and others, employ cooling systems that address passenger cooling and auxiliary cooling loads ranging from a few Watts to 50 kW or more. Such systems are typically powered using vapor-compression cooling systems that either directly supply cold air to the various locations, or cool an intermediate single-phase coolant closed loop, which in turn serves as the coolant for the passenger cabins and auxiliary loads such as electronics modules. Efforts are underway to enhance the performance of such systems, and also to develop more light weight and compact systems that would remove high heat fluxes. The distributed cooling configuration offers the advantage of a smaller refrigerant system package. The heat transfer between the intermediate fluid and air or with the auxiliary heat loads can be fine tuned through the control of flow rates and component sizes and controls to maintain tight tolerances on the cooling performance. Because of the additional loop involved in such a configuration, there is a temperature penalty between the refrigerant and the ultimate heat sink or source, but in some configurations, this may be counteracted through judicious design of the phase change-to-liquid coupled heat exchangers. Such heat exchangers are inherently smaller due to the high heat transfer coefficients in phase change and single-phase liquid flow compared to air flow. The additional loop also requires a pump to circulate the fluid, which adds pumping power requirements. However, a direct refrigerant-to-heat load coupling system might in fact be suboptimal if the heat loads are distributed across large distances. This is because of the significantly higher pressure drops (and saturation temperature drops) incurred in transporting vapor or two-phase fluids through refrigerant lines across long plumbing elements. An optimal system can be developed for any candidate application by assessing the tradeoffs in cooling capacity, heat exchanger sizes and configurations, and compression, pumping and fan power. In this study, a versatile simulation platform for a wide variety of direct and indirectly coupled cooling systems was developed to enable comparison of different component geometries and system configurations based on operating requirements and applicable design constraints. Components are modeled at increasing levels of complexity ranging from specified closest approach temperatures for key components to models based on detailed heat transfer and pressure drop models. These components of varying complexity can be incorporated into the system model as desired and trade-off analyses on system configurations performed. Employing this platform as a screening, comparison, and optimization tool, a number of conventional vapor-compression and distributed cooling systems were analyzed to determine the efficacy of the distributed cooling scheme in mobile cooling applications. Four systems serving approximately a 6 kW cooling duty, two with air-coupled evaporators and two with liquid-coupled evaporators, were analyzed for ambient conditions of 37.78°C and 40% relative humidity. Though the condensers and evaporators are smaller in liquid-coupled systems, the total mass of the heat exchangers in the liquid-coupled systems is larger due to the additional air-to-liquid heat exchangers that the configuration requires. Additionally, for the cooling applications considered, the additional compressor power necessitated by the liquid-coupled configuration and the additional power consumed by the liquid-loop pumps result in the coefficient of performance being lower for liquid-coupled systems than for air-coupled systems. However, the use of liquid-coupling in a system does meet the primary goal of decreasing the system refrigerant inventory by enabling the use of smaller condensers and evaporators and by eliminating long refrigerant carrying hoses.
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Černík, Václav. "Návrh vzduchotechniky a vytápění pro výrobní podnik." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230487.
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This master’s thesis deals with heating and HVAC in production plant ELMET, spol. s r.o. The first part of the thesis concerns reconstruction of the central heating system, which is outdated and unreliable in the time of the writing of the thesis. The second part deals with cooling of mounting of electronics, where technological requirements are not met due to summer overheating. The third part of the thesis concerns ventilation of metalworking hall using waste heat from production machines.
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Mednaoui, Hassan el. "Contribution à l'étude du comportement du cuivre en milieu marin côtier. : Aspects chimiques de la bioturbation de l'interface eau-sédiment par le gastéropode Hydrobia Ulvae." Pau, 1986. http://www.theses.fr/1986PAUU3002.
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Sazib, Nazmus Shams. "Physically Based Modelling of the Impacts of Climate Change on Streamflow Regime." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/5067.
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Understanding the implications of climate change on streamflow regime is complex as changes in climate vary over space and time. However, a better understanding of the impact of climate change is required for identifying how stream ecosystems vulnerable to these changes, and ultimately to guide the development of robust strategies for reducing risk in the face of changing climatic conditions. Here I used physically based hydrologic modeling to improve understanding of how climate change may impact streamflow regimes and advance some of the cyberinfrastructure and GIS methodologies that support physically based hydrologic modeling by: (1) using a physically based model to examine the potential effects of climate change on ecologically relevant aspects of streamflow regime, (2) developing data services in support of input data preparation for physically based distributed hydrologic models, and (3) enhancing terrain analysis algorithms to support rapid watershed delineation over large area. TOPNET, a physically based hydrologic model was applied over eight watersheds across the U.S to assess the sensitivity and changes of the streamflow regime due to climate change. Distributed hydrologic models require diverse geospatial and time series inputs, the acquisition and preparation of which are labor intensive and difficult to reproduce. I developed web services to automate the input data preparation steps for a physically based distributed hydrological model to enable water scientist to spend less time processing input data. This input includes terrain analysis and watershed delineation over a large area. However, limitations of current terrain analysis tools are (1) some support only a limited set of specific raster and vector data formats, and (2) all that we know of require data to be in a projected coordinate system. I enhanced terrain analysis algorithms to extend their generality and support rapid, web-based watershed delineation services. Climate change studies help to improve the scientific foundation for conducting climate change impacts assessments, thus building the capacity of the water management community to understand and respond to climate change. Web-based data services and enhancements to terrain analysis algorithms to support rapid watershed delineation will impact a diverse community of researchers involved terrain analysis, hydrologic and environmental modeling.
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Silva, João José Aires Afonso Génio da. "Estudo do ciclo reprodutor e crescimento de Hydrobia ulvae (Pennant, 1777) na Ria de Aveiro e suas implicações no âmbito da biomonitorização da poluição por TBT." Master's thesis, Universidade de Aveiro, 2002. http://hdl.handle.net/10773/21785.
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Mestrado em Ciências das Zonas CosteirasCom o objectivo de contribuir para a validação da utilização de Hydrobia ulvae em programas de biomonitorização da poluição por tributilestanho (TBT) na Ria de Aveiro, foi estudado o seu ciclo reprodutor, crescimento e imposexo num banco de lodo situado na Ermida (Canal de Ílhavo – Ria de Aveiro). O local de estudo foi amostrado no período de baixa-mar, entre Dezembro de 1999 e Dezembro de 2000, com uma periodicidade aproximadamente mensal. O estudo histológico das gónadas de Hydrobia ulvae revelou a existência de uma época de desova muito alargada, que ocorreu, provavelmente, entre Julho e Fevereiro. O comprimento médio do pénis dos machos variou ao longo do ciclo reprodutor, atingindo valores mais elevados entre o fim do Verão e o início do Outono, época em que a maturação das gónadas foi mais intensa. A análise de histogramas de frequência da altura das conchas de Hydrobia ulvae ao longo do período de estudo revelou a ocorrência de quatro episódios de recrutamento, em Março, Maio, Julho e Setembro, compostos por animais com uma altura média da concha entre 1,2 e 1,8 mm. Estima-se que, a partir desse momento, estes indivíduos terão crescido até 6,4 - 6,8 mm ao fim de 17-21 meses. A longevidade foi calculada em cerca de 2 anos. Verificou-se, também, a ocorrência de uma variação sazonal na taxa de crescimento, com valores nulos no Inverno e máximos entre a Primavera e o Outono. Os índices de imposexo – VDS (sequência do vaso deferente), FPL (comprimento médio do pénis das fêmeas) e %FA (percentagem de fêmeas afectadas) – não apresentaram um padrão de variação sazonal ao longo do período de estudo, mas antes oscilações erráticas em torno de um valor médio de 1,0, 0,4 e 89%, respectivamente. A evolução do índice de imposexo RPL (comprimento relativo do pénis das fêmeas) foi, em parte, influenciada pela variação sazonal do comprimento médio do pénis dos machos. Não se observaram comportamentos migratórios importantes de Hydrobia ulvae no local de estudo que tenham influenciado a evolução dos níveis de imposexo da população ao longo do ano. Considerando que o valor do índice RPL depende da variação sazonal do comprimento médio do pénis dos machos, a comparação deste índice entre populações só é válida se as mesmas se encontrarem em idêntico estádio do ciclo reprodutor. Visto que os indivíduos adultos seleccionados para os estudos de imposexo são substituídos anualmente por animais recrutados no ano anterior, as campanhas de biomonitorização efectuadas com uma periodicidade anual podem mostrar uma eventual diminuição dos níveis de poluição por TBT no futuro.
The reproductive cycle, growth and imposex of Hydrobia ulvae were studied at a muddy flat located at Ermida (Canal de Ílhavo – Ria de Aveiro), aiming the validation of this species for tributyltin (TBT) pollution monitoring in the Ria de Aveiro. Sampling was performed at approximately monthly intervals, during low tide, from December 1999 to December 2000. The histological study of the gonads of Hydrobia ulvae showed that egg spawning occurred during a long period, probably from July to February. A variation of the male penis length was observed along the reproductive cycle, with maximum values registered during the ripening of the testis, which occurred mainly between late summer and early fall. The analysis of the frequency histograms of the Hydrobia ulvae shell height showed the occurrence of four annual recruitments - in March, May, July and September - composed by animals with 1.2-1.8 mm shell height. These specimens probably grew up to 6.4 - 6.8 mm after 17-21 months. The longevity was estimated to be of about 2 years. There was a clear seasonal variation of the growth rate with null values in the winter and maximum values between the spring and the fall. The evolution of the imposex indices along the year – VDS (vas deferens sequence), FPL (female penis length) and %FA (percentage of affected females) – didn't show any seasonal pattern but rather an erratic oscillation around a mean value of 1.0, 0.4 and 89%, respectively. However, the evolution of the RPL (relative penis length) index was, in part, induced by the seasonal variation of the male penis length. Hydrobia ulvae did not show strong migratory movements at the sampling station that could have influenced the imposex levels of the population. Considering that RPL is influenced by the variation of the male penis length, the use of RPL for imposex comparisons between populations ought to be performed on individuals at approximately the same reproductive stage. Since the specimens selected for imposex studies are substituted every year in the population by the animals recruited one year before, the biomonitoring surveys that are repeated on an annual basis may depict any possible reduction of TBT pollution levels in the future.
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Ottery, Peter. "Using differential adhesion to control self-assembly and self-repair of collections of modular mobile robots." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/1396.
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This thesis presents a novel distributed control method which allows a collection of independently mobile robotic units, with two or three dimensional movement, to self-assemble into self-repairing hierarchical structures. The proposed method utilises a simple model of the cellular adhesion mechanisms observed in biological cells, allowing the robotic units to form virtually bonded aggregates which behave as predicted by Steinberg’s differential adhesion hypothesis. Simulated robotic units based on the design of the subaquatic HYDRON module are introduced as a possible platform on which the model can be implemented. The units are used to carry out a detailed investigation of the model behaviour and parameter space focusing on the two main tasks of rounding and sorting in both two and three dimensions. These tasks assess the model’s ability to reach a thermodynamically stable configuration when the aggregates consist of either a single population of units or multiple populations of units with differing adhesive properties. The results are analysed in detail with particular attention given to the role of random movements in determining the overall performance, and demonstrate that this model provides a very robust solution to these complex tasks. Finally, a possible extension of this work is presented in which the original model is combined with a genetic regulatory network controller. The performance of this composite is evaluated, and the benefits of this hybrid approach, in which a powerful control system manipulates a robust self-organising behaviour, are discussed.
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Saito, Renata Mayumi. "Utilização da eletroforese capilar com eletrólitos não-tamponado para o estudo do comportamento dos íons hidrônio e hidroxila e seu desdobramento analítico." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-14082007-151644/.
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Neste trabalho, foram efetuados estudos sobre o comportamento eletroforético dos íons hidrônio (H3O+) e hidroxila (OH-) utilizando eletroforese capilar em zona em meio não-tamponado e detecção condutométrica sem contato. Alterações na composição do eletrólito de corrida devido à eletrólise foram evitadas empregando um sistema de eletrólise separada. A determinação de ácidos com pKas menores ou iguais ao pH do eletrólito de corrida foi possível. A possibilidade da análise em bases fortes também foi demonstrada. Eletrólitos de corrida com pH entre 4,5 e 7,0 (para o H3O+) e entre 7,0 e 9,0 (para o OH-) mostraram-se favoráveis para a análise. Ambas as espécies apresentaram interação com os grupos silanóis do capilar. Dificuldades na análise do íon OH- decorreram também de: reação da sílica com o analito e com o eletrólito de corrida e absorção de CO2 atmosférico. A mobilidade do íon H3O+ medida foi 8% abaixo da obtida por outras técnicas. A curva para determinação de OH- em base forte, com solução de trifluoracetato de lítio 10 mmol L-1 (pH 8,5) como eletrólito de corrida, mostrou boa linearidade na faixa de 0,5 a 7,0 mmol L-1. As curvas de quantificação de H3O+ titulável em amostras de ácidos fortes, fracos e suas misturas, com solução de LiCl (pH 5,5) como eletrólito de corrida, apresentaram ampla faixa de resposta linear, com boa linearidade, ao redor de 0,05 a 10 mmol L-1.In this work, studies about the electrophoretic behavior of hydronium (H3O+) and hydroxyl (OH-) ions using capillary zone electrophoresis in unbuffered medium and contactless conductity detection were developed. Variations in running electrolyte composition due to electrolysis were avoided using an electrolysis separated system. The analysis of acids with the same or lower pKa than the running electrolyte pH was possible. The possibility of strong bases analysis was demonstrated as well. Good results were achieved using running electrolytes with pH between 4.5 and 7.0, for H3O+ analysis, and between 7.0 and 9.0, for OH- analysis. Both species interacted with the silanol groups of silica capillary. Other problems in the determination of OH- were: reaction of silica with the analyte as well as with the running electrolyte and absorption of atmospheric CO2. The H3O+ mobility calculated was 8% lower than values obtained in the literature. Analytical curve of OH- ion in strong base, using 10 mmol L-1 litium trifluoracetate (pH 8.5) as running electrolyte, resulted in good linearity in a range of 0.5 to 7.0 mmol L-1. Analytical curves of titrable hydronium ion in samples of strong and weak acids, as well in their mixture, using 10 mmol L-1 LiCl (pH 5.5) as running electrolyte, resulted in wide linear range (0.05 mmol L-1 to 10 mmol L-1).
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Mabrouki, Ridha Ben Mohsen. "Drift Tube Ion Mobility Measurements for Thermochemistry, Kinetics and Polymerization of Cluster Ions." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd/1165.
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In this work, the Drift Tube Ion Mobility technique is used to study the hydrophobic hydration and solvation of organic ions and measure the thermochemistry and kinetics of ion-molecule reactions. Furthermore, an exploratory study of the intracluster polymerization of isoprene will be presented and discussed. The ion hydration study is focused on the C3H3+ cation1 and Pyridine▪+ radical cation.2 The chemistry of the cyclic C3H3+ cation1 has received considerable attention and continues to be an active area of research.3-7 The binding energies of the first 5 H2O molecules to c-C3H3+ were determined by equilibrium measurements. The measured binding energies of the hydrated clusters of 9-12 kcal/mol are typical of carbon-based CH+X hydrogen bonds. The ion solvation with the more polar CH3CN molecules results in stronger bonds consistent with the increased ion-dipole interaction. Ab initio calculations show that the lowest energy isomer of the c-C3H3+(H2O)4 cluster consists of a cyclic water tetramer interacting with the c-C3H3+ ion, which suggests the presence of orientational restraint of the water molecules consistent with the observed large entropy loss. The c-C3H3+ ion is deprotonated by 3 or more H2O molecules, driven energetically by the association of the solvent molecules to form strongly hydrogen bonded (H2O)nH+ clusters. The kinetics of the associative proton transfer (APT) reaction C3H3+ + nH2O → (H2O)nH+ + C3H2 exhibits an unusually steep negative temperature coefficient of k = cT(sup>63±4 (or activation energy of -32 ± 1 kcal mol-1). The behavior of the C3H3+/water system is exactly analogous to the benzene+ /water system8,9, suggesting that the mechanism, kinetics and large negative temperature coefficients may be general to multibody APT reactions. These reactions can become fast at low temperatures, allowing ionized polycyclic aromatics to initiate ice formation in cold astrochemical environments.The solvation energies of the pyridine+ radical cation by 1- 4 H2O molecules are determined by equilibrium measurements in the drift cell. The binding energies of the pyridine+(H2O)n clusters are similar to the binding energies of protonated pyridineH+(H2O)n clusters that involve NH+∙∙OH2 bonds, and different from those of the solvated radical benzene+(H2O)n ions that involve CHδ+∙∙OH2 bonds. These relations indicate that the observed pyridine+ ions have the distonic C5H4NH+ structure that can form NH+∙∙OH2 bonds. The observed thermochemistry and ab initio calculations show that these bonds are not affected significantly by an unpaired electron at another site of the ion. The distonic structure is also consistent with the reactivity of pyridine+ in H atom transfer, intra-cluster proton transfer and deprotonation reactions. The results present the first measured stepwise solvation energies of distonic ions, and demonstrate that cluster thermochemistry can identify distonic structures.The gas phase clustering of small molecules around the hydronium ion is of fundamental interest and is relevant to important atmospheric and astrophysical processes. In this work, the equilibrium constants for the formation of the H3O+(X)n clusters with X = H2, N2 and CO and n = 1-3 at different temperatures are measured using the drift tube technique10. The arrival time distributions (ATDs) of the injected H3O+ and the H3O+(X)n clusters formed inside the cell are measured under equilibrium conditions. The resulting binding energies for the addition of one and two hydrogen molecules are similar [3.4 and 3.5 kcal/mol, respectively). For the N2 clustering with n = 1-3, the measured binding energies are 7.9, 6.9 and 5.4 kcal/mol, respectively. The clustering of CO on the H3O+ ion exhibits a relatively strong binding energy (11.5 kcal/mol) consistent with the dipole moment and polarizability of the CO molecule. Theoretical calculations of the lowest energy structures are correlated to the experimental results. Finally, intracluster polymerization leading to the formation of covalent bonded oligomer ions has been investigated following the ionization of neutral isoprene clusters. The results indicate that isoprene dimer cation has a structure similar to that of the limonene radical cation. Mass-selected mobility and dissociation studies also indicate that the larger isoprene cluster ions have covalent bonded structures. The conversion of molecular clusters into size-selected oligomers is an important process not only for detailed understanding of the early stages of polymerization but also for practical applications such as the formation of new polymeric materials with controlled and unusual properties.