24 research outputs found
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Preparation of films of a highly aligned lipid cubic phase
We demonstrate a method by which we can produce an oriented film of an inverse bicontinuous cubic phase (QII D) formed by the lipid monoolein (MO). By starting with the lipid as a disordered precursor (the L3 phase) in the presence of butanediol, we can obtain a film of the QII D phase showing a high degree of in-plane orientation by controlled dilution of the sample under shear within a linear flow cell. We demonstrate that the direction of orientation of the film is different from that found in the oriented bulk material that we have reported previously; therefore, we can now reproducibly form QII D samples oriented with either the [110] or the [100] axis aligned in the flow direction depending on the method of preparation. The deposition of MO as a film, via a moving fluid− air interface that leaves a coating of MO in the L3 phase on the capillary wall, leads to a sample in the [110] orientation. This contrasts with the bulk material that we have previously demonstrated to be oriented in the [100] direction, arising from flow producing an oriented bulk slug of material within the capillary tube. The bulk sample contains significant amounts of residual butanediol, which can be estimated from the lattice parameter of the QII D phase obtained. The sample orientation and lattice parameters are determined from synchrotron small-angle X-ray scattering patterns and confirmed by simulations. This has potential applications in the production of template materials and the growth of protein crystals for crystallography as well as deepening our understanding of the mechanisms underlying the behavior of lyotropic liquid-crystal phases
Influence of clay content and amount of organic modifiers on morphology and pervaporation performance of EVA/clay nanocomposites
Poly(ethylene-co-vinyl acetate)/organically modified clay nanocomposites were prepared using different clay loadings and by varying the amount of organic modifier. The morphology of the nanocomposites was investigated using small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). SAXS results displayed intercalation of polymeric chains between the silicate layers in all the cases. The interlayer distance varies slightly between the series. TEM images showed a better dispersion of the clay platelets at lower loading for both series of samples. The pervaporation performances of membranes were analyzed using a chloroform/acetone mixture. Membranes displayed high selectivity. The influence of feed composition on pervaporation was analyzed. The nanoclay content and the influence of free volume on pervaporation performance were also investigated in detail. A drop in selectivity and an increase in permeation rate were observed at higher clay loadings
A Multitechnique Study of Structure and Dynamics of Polyfluorene Cast Films and the Influence on Their Photoluminescence
This article describes the microstructure and dynamics in the solid state of polyfluorene-based polymers, poly(9,)-dioctylfluorenyl-2,7-diyl) (PFO), a semicrystalline polymer, and poly [(9,9-dioctyl- 2,7-divinylene-fluorenylene)-alt-co-{2-methoxy-5-(2-ethyl-hexyloxy)- 1,4-phenylene vinylene}, a copolymer with mesomorphic phase properties. These Structures were determined by wide-angle X-ray scattering (WAXS) measurements, Assuming a packing model for the copolymer structure, where the planes of the phenyl rings are stacked and separated by an average distance of similar to 4.5 angstrom and laterally spaced by about similar to 16 angstrom, we followed the evolution of these distances as a function of temperature using WAXS and associated the changes observed to the polymer relaxation processes identified by dynamical mechanical thermal analysis. Specific molecular motions were studied by solid-state nuclear magnetic resonance. The onset of the side-chain motion at about 213 K (beta-relaxation) produced a small increase in the lateral spacing and in the stacking distance of the phenyl rings in them aggregated Structures, Besides, at about 383 K (alpha-relaxation) there occurs a significant increase in the amplitude of the torsion motion in the backbone, producing a greater increase in the stacking distance of the phenyl rings. Similar results were observed in the semicrystalline phase of PFO, but in this case the presence of the crystalline structure affects considerably the overall dynamics, which tends to be more hindered. Put together, Our data explain many features of the temperature dependence of the photoluminescence of these two polymers.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESPCNPqConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)MCT/INEOMinistério da Ciência, Tecnologia e Inovação do Brasil (MCTI)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPESBrazilian Synchrotron Light Laboratory (LNLS)[D02ASAXS2]Brazilian Synchrotron Light Laboratory (LNLS)Brazilian Synchrotron Light Laboratory (LNLS)Brazilian Synchrotron Light Laboratory (LNLS)[D11A-SASX5379
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Proportionaaliventtiilien elinkaaren analyysi
TIIVISTELMÄ
Kemi-Tornion ammattikorkeakoulu, Tekniikan yksikkö
Koulutusohjelma Sähkötekniikka
Opinnäytetyön tekijä Mikko Aarni
Opinnäytetyön nimi Proportionaaliventtiilien elinkaaren analyysi
Työn laji Opinnäytetyö
päiväys 29.3.2011
sivumäärä 56 + 5 liitesivua
Opinnäytetyön ohjaaja DI Tuomas Pussila
Yritys Outokumpu Oyj
Yrityksen yhteyshenkilö/valvoja Insinööri Sauli Kiiskilä
Tämä opinnäytetyö on tehty Outokumpu Oyj:lle Tornion tehtaiden kylmävalssaamolle. Kylmävalssaamolta työn valvojana toimi kunnossapitoinsinööri Sauli Kiiskilä.
Työssä keskitytään tehtaan kylmävalssaamossa esiin tulleen ongelman selvittämiseen. Laitekanta on osittain päässyt vanhentumaan, jolloin on syytä selvittää kaikkien tarpeellisten uusien korvaavien laitteiden saatavuus tarvittaessa. Samalla pyritään laatimaan menetelmä proportionaaliventtiilien käyttöiän määrittämiseksi. Tietoa voisi ehkä hyödyntää välttämättömien huoltoseisokkien yhteydessä, jolloin ehkä voisi vaihtaa myös lähiaikoina käyttöikänsä loppuun tulevat venttiilit ja siten välttyä linjan pysähtymiseltä kesken tuotantoprosessin vältettävissä olevan laiterikon takia.
Kirjallisuusosassa kuvattiin tuotantoprosessia, hydrauliikan ja kunnossapidon perusteita sekä tuotantoyksikössä käytössä olevaa kunnossapitojärjestelmää.
Kokeellisessa osassa tehtiin piirikaavioista saatujen tietojen perusteella taulukko, josta selviää positio, proportionaaliventtiilin tyyppi ja VT-ohjauskortti. Proportionaaliventtiilien tyyppitietojen tarkistaminen sekä täydentäminen suoritettiin kiertämällä kaikki tuotantolinjat läpi ja käymällä läpi jokaisen yksittäisen proportionaaliventtiilin tyyppi. Koska joitakin poikkeamia oli vuosien varrella tehtyjen huoltojen yhteydessä jostakin syystä merkintöihin tullut, saatettiin listat ajan tasalle. Päivitetyt tiedot merkittiin kunnossapitojärjestelmä Kutiin. Samassa yhteydessä luotiin Kutiin myös järjestelmä, jossa jokaisen proportinaaliventtiilin käyttöikä rekisteröitiin ja näin luotiin perusdata, josta voidaan myöhemmin määritellä keskimääräinen käyttöikä kullekin venttiilityypille.
Asiasanat: automaatio, analyysi, dokumentointi, elinkaari.ABSTRACT
Kemi-Tornio University of Applied Sciences, Technology
Degree Programme Electrical Engineering
Name Mikko Aarni
Title The Life Cycle of the Proportional Valve
Type of Study Bachelor’s Thesis
Date 29 March 2011
Pages 57 + 5 appendices tai appendixes
Instructor Instructor Tuomas Pussila, MSc, (Tech.)
Company Outokumpu Oyj
ContactPerson/Supervisor
from Company Sauli Kiiskilä, MechEng Outokumpu Oyj
This study is done at the coldrolling productionlines of the Outokumpu Tornio Works under the Supervisor Sauli Kiiskilä, MechEng Outokumpu Oyj.
The purpose of the job was to make the life cycle analysis of the proportional valves on the HP-3-line and the prepairingline and update the register of the equipments. The outdated equipments should be found and prepaired to substitude by the corresponding equipments.
At the literature part was described the production process, the basics of the hydraulics and the basics of the preventive maintenance and the actual maintenance system.
At the working part of the study the table was created where the position, the type of the proportional valve and the VT-control card can be found. The table was
controlled by checking all the individual valves in the production lines and the errors were prepaired. All the new data was put into the Maintenance System Kuti. At the same time the working time of all the individual proportional valves was observed and the data was created, where the average life time of the valves can be calculated after some months and years
Temperature dependence of molecular dynamics and supramolecular aggregation in MEH-PPV films: A solid-state NMR, X-ray and fluorescence spectroscopy study
This article presents an investigation of the temperature induced modification in the microstructure and dynamics of poly[2-methoxy-5-(2`-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) cast films using Wide-Angle X-ray Scattering (WAXS), solid-state Nuclear Magnetic Resonance (NMR), and Fluorescence Spectroscopy (PL). MEH-PPV chain motions were characterized as a function of temperature by NMR. The results indicated that the solvent used to cast the films influences the activation energy of the side-chain motions. This was concluded from the comparison of the activation energy of the toluene cast film, E(a) = (54 +/- 8) kJ/mol, and chloroform cast film, E(a) = (69 +/- 5) kJ/mol, and could be attributed to the higher side-chain packing provided by chloroform, that preferentially solvates the side chain in contrast to toluene that solvates mainly the backbone. Concerning the backbone mobility, it was observed that the torsional motions in the MEH-PPV have average amplitude of similar to 10 degrees at 300 K, which was found to be independent of the solvent used to cast the films. In order to correlate the molecular dynamics processes with the changes in the microstructure of the polymer, in situ WAXS experiments as a function of temperature were performed and revealed that the interchain spacing in the MEH-PPV molecular aggregates increases as a function of temperature, particularly at temperatures where molecular relaxations occur. It was also observed that the WAXS peak associated with the bilayer spacing becomes narrower and its intensity increases whereas the peak associated with the inter-backbone planes reduces its intensity for higher temperatures. This last result Could be interpreted as a decrease in the number of aggregates and the reduction of the interchain species during the MEH-PPV relaxation processes. These WAXS results were correlated with PL spectra modifications observed upon temperature treatments. (C) 2008 Elsevier Ltd. All rights reserved.FAPESPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPqCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPESMinistério da Ciência, Tecnologia e Inovação do Brasil (MCTI)MCT/PADCT/IMMPFundo de Apoio ao Ensino, à Pesquisa e Extensão - FAEPEX-UNICAMPFAEPEX/Unicam
Ciprofloxacin intercalated in fluorohectorite clay : Identical pure drug activity and toxicity with higher adsorption and controlled release rate
Different natural clay minerals, including halloysite, montmorillonite and kaolinite, have been proven to be efficient drug carriers providing for high and long lasting drug concentrations owing to their adsorption capacity and ion exchange property. Synthetic clays, however, are advantageous over the natural clay minerals in terms of purity of composition and controllable cation exchange capacity, factors that contribute to improve reproducibility of the host system. Here we studied a synthetic smectite clay as a candidate for high adsorption and controlled release rate. Via X-ray powder diffraction we verified that, under acidic conditions, the antibiotic ciprofloxacin was successfully incorporated in the synthetic clay fluorohectorite, while via UV-VIS spectroscopy we showed that the degree of the drug incorporation is at least 25% higher than for other systems reported in the literature. Furthermore, temperature dependent release studies allowed us to show that the release process is thermally activated and diffusion-controlled. Finally, via bacterial and toxicological tests, we demonstrated that the effectiveness and toxicity of pure ciprofloxacin is unaffected in the clay-drug complex