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Assessment of anaerobic sewage sludge quality for agricultural application after metal bioleaching

Villar, L. D.; Garcia, O.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1553-1559
ENG
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The effects of metal bioleaching on nutrient solubilization, especially nitrogen and phosphorous, from anaerobically-digested sewage sludge were investigated in this work. The assessment of the sanitary quality of the anaerobic sludge after bioleaching was also carried out by enumerating indicator (total coliforms, fecal coliforms, and fecal streptococci) and total heterotrophic bacteria. The experiments of bioleaching were performed using indigenous sulphur-oxidizing bacteria (Thiobacillus spp.) as inoculum and samples of anaerobically-digested sludge. Nitrogen and phosphorous solubilization from sewage sludge was assessed by measuring, respectively, the concentration of Total Kjeldahl Nitrogen, ammonia, nitrate/nitrite, and soluble and total phosphorous before and after the bioleaching assays. At the end of the experiment, after 4 days of incubation (final pH of 1.4), the following metal solubilization yields were obtained: zinc, 91%; nickel, 87%; copper, 79%; lead, 52%; and chromium, 42%. As a result of sludge acidification, the viable counts of selected indicator bacteria were decreased to below the detection limit (4 × 103 cfu 100 ml-1), followed by an increase in the mineral fraction of nitrogen (from 6 to 10%) and in the soluble fraction of phosphorous (from 15 to 30%). Although some loss of sludge nutrients can occur during solid-liquid separation following bioleaching...

Metalização mecânica para brasagem de uniões ZrO2/metal e ZrO2/ZrO2

Pimenta, Jean Senise
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Tese de Doutorado Formato: xxiv, 233 p.| il., grafs., tabs.
POR
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Gradução em Engenharia Mecânica, Florianópolis, 2010; No presente trabalho empregou-se a técnica de metalização mecânica na produção de um revestimento de metal ativo (Ti ou Zr) para reduzir superficialmente a zircônia e favorecer o molhamento com ligas de adição convencionais. A interface resultante foi caracterizada por técnicas de análise microestrutural. Posteriormente, avaliou-se o desempenho de juntas brasadas estanques cerâmica/metal e cerâmica/cerâmica por meio de testes de microdureza e resistência mecânica à flexão-3p. A condição de molhamento foi analisada em substratos metalizados constituídos por zircônia (ZrO2) estabilizada com ítria ou magnésia, usando-se as ligas Ag-28Cu e Au-18Ni nos respectivos ciclos térmicos. Os melhores resultados dos testes de molhamento foram selecionados para os testes de brasagem indireta em forno de alto-vácuo (<3 10-5 mbar) e metalização com Ti. Os ângulos de contato medidos em decorrência da metalização prévia com Zr foram consideravelmente elevados, afetando a qualidade do molhamento das ligas fundidas. Juntas cerâmica/metal e cerâmica/cerâmica brasadas com a liga Ag-28Cu e metalização com Ti apresentaram ótima estanqueidade nos testes de detecção de vazamento de gás hélio a temperatura ambiente. Entretanto...

The use of a metal detector to locate ingested metallic foreign bodies in children.

Tidey, B; Price, G J; Perez-Avilla, C A; Kenney, I J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1996 EN
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OBJECTIVE: A pilot study to assess whether modern metal detectors can reduce unnecessary radiation in searching for ingested metallic foreign bodies. METHODS: Over a one year period, 20 children presenting to an accident and emergency department with suspected metallic foreign body ingestion were studied. Using an Adams Electronics AD15 metal detector, the radiographer recorded the location of metallic foreign bodies on a pictorial representation of neck, chest, and abdomen. The child then had plain radiographs of abdomen, chest, and neck in sequential order until the foreign body was located. RESULTS: In seven cases neither metal detector nor radiography revealed a foreign body (true negatives). In the remaining 13 cases where metal detection was positive, subsequent radiography or faecal search was also positive (true positives). The 13 foreign bodies were coins (8), gold ring (1), ball bearing (1), screw (1), staple (1), and washer (1). All were in the stomach or proximal small bowel on radiography except for one coin in the right iliac fossa. CONCLUSIONS: The detector can demonstrate ingested metallic foreign bodies reliably in children, thereby reducing unnecessary irradiation.

Detection of Cd, Pb, and Cu in Non-Pretreated Natural Waters and Urine with Thiol Functionalized Mesoporous Silica and Nafion Composite Electrodes

Yantasee, Wassana; Charnhattakorn, Busarakum; Fryxell, Glen E.; Lin, Yuehe; Timchalk, Charles; Addleman, R. Shane
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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37.276533%
Electrochemical sensors have great potential for environmental monitoring of toxic metal ions in waters due to their portability, field-deployability and excellent detection limits. However, electrochemical sensors employing mercury-free approaches typically suffer from binding competition for metal ions and fouling by organic substances and surfactants in natural waters, making sample pretreatments such as wet ashing necessary. In this work, we have developed mercury-free sensors by coating a composite of thiol self-assembled monolayers on mesoporous supports (SH-SAMMS™) and Nafion on glassy carbon electrodes. With the combined benefit of SH-SAMMS™ as an outstanding metal preconcentrator and Nafion as an antifouling binder, the sensors could detect 0.5 ppb of Pb and 2.5 ppb of Cd in river water, Hanford groundwater, and seawater with a minimal amount of preconcentration time (few minutes) and without any sample pretreatment. The sensor could also detect 2.5 ppb of Cd, Pb, and Cu simultaneously. The electrodes have long service times and excellent single and inter-electrode reproducibility (5% RSD after 8 consecutive measurements). Unlike SAMMS™-carbon paste electrodes, the SAMMS™-Nafion electrodes were not fouled in samples containing albumin and successfully detected Cd in human urine. Other potentially confounding factors affecting metal detection at SAMMS™-Nafion electrodes were studied...

Development of a novel polymeric fiber-optic magnetostrictive metal detector

Hua, Wei-Shu; Hooks, Joshua Rosenberg; Wu, Wen-Jong; Wang, Wei-Chih
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
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The purpose this paper is the development a novel polymeric fiber-optic magnetostrictive metal detector, using a fiber–optic Mach-Zehnder interferometer and polymeric magnetostrictive material. Metal detection is based on the strain-induced optical path length change steming from the ferromagnetic material introduced in the magnetic field. Varied optical phase shifts resulted largely from different metal objects. In this paper, the preliminary results on the different metal material detection will be discussed.

Fiberoptic metal detector capable of profile detection

Hua, Wei-Shu; Hooks, Joshua R.; Erwin, Nicholas A.; Wu, Wen-Jong; Wang, Wei-Chih
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 31/03/2011 EN
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The purpose of this paper is to develop a novel ferromagnetic polymeric metal detector system by using a fiber-optic Mach-Zehnder interferometer with a newly developed ferromagnetic polymer as the magnetostrictive sensing device. This ferromagnetic polymeric metal detector system is simple to fabricate, small in size, and resistant to RF interference (which is common in typical electromagnetic type metal detectors). Metal detection is made possible by disrupting the magnetic flux density present on the magnetostrictive sensor. This paper discusses the magnetic properties of the ferromagnetic polymers. In addition, the preliminary results of successful sensing of different geometrical metal shapes will be discussed.

Discrimination between Weaned and Unweaned Atlantic Cod (Gadus morhua) in Capture-Based Aquaculture (CBA) by X-Ray Imaging and Radio-Frequency Metal Detector

Misimi, Ekrem; Martinsen, Svein; Mathiassen, John Reidar; Erikson, Ulf
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 17/04/2014 EN
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37.195615%
The aim of this study was to investigate the feasibility of two detection methods for use in discrimination and sorting of adult Atlantic cod (about 2 kg) in the small scale capture-based aquaculture (CBA). Presently, there is no established method for discrimination of weaned and unweaned cod in CBA. Generally, 60–70% of the wild-caught cod in the CBA are weaned into commercial dry feed. To increase profitability for the fish farmers, unweaned cod must be separated from the stock, meaning the fish must be sorted into two groups – unweaned and weaned from moist feed. The challenges with handling of large numbers of fish in cages, defined the limits of the applied technology. As a result, a working model was established, focusing on implementing different marking materials added to the fish feed, and different technology for detecting the feed presence in the fish gut. X-ray imaging in two modes (planar and dual energy band) and sensitive radio-frequency metal detection were the detection methods that were chosen for the investigations. Both methods were tested in laboratory conditions using dead fish with marked feed inserted into the gut cavity. In particular, the sensitive radio-frequency metal detection method with carbonyl powder showed very promising results in detection of marked feed. Results show also that Dual energy band X-ray imaging may have potential for prediction of fat content in the feed. Based on the investigations it can be concluded that both X-ray imaging and sensitive radio-frequency metal detector technology have the potential for detecting cod having consumed marked feed. These are all technologies that may be adapted to large scale handling of fish from fish cages. Thus...

Development of a polymer based fiberoptic magnetostrictive metal detector system

Hua, Wei Shu; Hooks, Joshua Rosenberg; Wu, Wen Jong; Wang, Wei Chih
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/2010 EN
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This paper presents a new metal detector using a fiberoptic magnetostriction sensor. The metal sensor uses a fiber-optic Mach-Zehnder interferometer with a newly developed ferromagnetic polymer as the magnetostrictive sensing material. This polymeric magnetostrictive fiberoptic metal sensor is simple to fabricate, small in size, and resistant to RF interference (which is common in typical electromagnetic type metal detectors). Metal detection is based on disruption of the magnetic flux density across the magnetostriction sensor. In this paper, characteristics of the material being sensed and magnetic properties of the ferromagnetic polymers will be discussed.

Molecular Engineering of Amphiphilic Pyridine Incorporated Conjugated Polymers for Metal Ion Sensors

Vetrichelvan, Muthalagu; Valiyaveettil, Suresh
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 409386 bytes; application/pdf
EN_US
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Recent developments in the synthesis and structure-property investigation studies of conjugated polymers have led to the design of novel polymeric materials with tailored properties for advanced technological applications. A promising development in this direction involves the fabrication of conducting polymer based sensors for the detection of metal ions and small organic molecules. Herein, we designed, synthesized and studied a series of amphiphilic copolymers containing alternate phenylene and 2,5- or 2,6- or 3,5-substituted pyridine rings. The basic N-atom of the pyridine ring and the adjacent –OH group from the phenyl ring provide binding sites for metal ions. Thermal properties, and optical properties of polymers in presence of acid, base and metal ions are investigated. A few target polymers showed high sensitivities for metal ions in solution.; Singapore-MIT Alliance (SMA)

Transition metal ion-substituted polyoxometalates entrapped into polypyrrole as electrochemical sensor for hydrogen peroxide

Anwar, Nargis; Vagin, Mikhail; Laffir, Fathima R.; Armstrong, Gordon; Dickinson, Calum; McCormac, Timothy
Fonte: Royal Society of Chemistry Publicador: Royal Society of Chemistry
Tipo: info:eu-repo/semantics/article; all_ul_research; ul_published_reviewed
ENG
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peer-reviewed; A conducting polymer was used for the immobilization of various transition metal ion-substituted Dawson-type polyoxometalates (POMs) onto glassy carbon electrodes. Voltammetric responses of films of different thicknesses were stable within the pH domain 2-7 and reveal redox processes associated with 10 the conducting polymer, the entrapped POMs and incorporated metal ions. The resulting POM doped polypyrrole films were found to be extremely stable towards redox switching between the various redox states associated with the incorporated POM. An amperometric sensor for hydrogen peroxide detection based upon the POM doped polymer films was investigated. The detection limits were 0.3 and 0.6 uM, for the Cu2+- and Fe3+-substituted POM-doped polypyrrole films respectively, with a linear region from 15 0.1 up to 2mM H2O2. Surface characterization of the polymer films was carried out using atomic force microscopy, x-ray photoelectron spectroscopy and scanning electron microscopy.

GPR development for landmine detection

Sato, Motoyuki; Fujiwara, Jun; Feng, Xuan; Zhou, Zheng-Shu; Kobayashi, Takao
Fonte: Korean Society of Exploration Geophysicists Publicador: Korean Society of Exploration Geophysicists
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
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Under the research project supported by Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), we have conducted the development of GPR systems for landmine detection. Until 2005, we have finished development of two prototype GPR systems, namely ALIS (Advanced Landmine Imaging System) and SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar). ALIS is a novel landmine detection sensor system combined with a metal detector and GPR. This is a hand-held equipment, which has a sensor position tracking system, and can visualize the sensor output in real time. In order to achieve the sensor tracking system, ALIS needs only one CCD camera attached on the sensor handle. The CCD image is superimposed with the GPR and metal detector signal, and the detection and identification of buried targets is quite easy and reliable. Field evaluation test of ALIS was conducted in December 2004 in Afghanistan, and we demonstrated that it can detect buried antipersonnel landmines, and can also discriminate metal fragments from landmines. SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar) is a machine mounted sensor system composed of B GPR and a metal detector. The GPR employs an array antenna for advanced signal processing for better subsurface imaging. SAR-GPR combined with synthetic aperture radar algorithm...

Considerations on the use of commercially available yeast biomass for the treatment of metal-containing effluents

Simmons, Paul; Tobin, John M.; Singleton, Ian
Fonte: Society for Industrial Microbiology Publicador: Society for Industrial Microbiology
Tipo: Artigo de Revista Científica
Publicado em //1995 EN
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Three strains ofSaccharomyces cerevisiae and one strain of aCandida sp. obtained from different industrial sources were screened for uptake of silver and copper. Considerable differences in metal uptake capacities were found between the different strains ofS. cerevisiae and betweenS. cerevisiae and theCandida sp. used. Copper uptake capacities ranged from 0.05 mmol g−1 dry wt to 0.184 mmol g−1 dry wt while values of 0.034 mmol Ag g−1 dry wt and 0.193 mmol Ag g−1 dry wt biomass were observed. Use of ion-selective electrodes (ISEs) enabled the detection of copper complexing agents (possibly proteins and carbohydrates) released by yeasts into the surrounding medium. In contrast, these compounds had no silver complexation abilities. Langmuir and Scatchard transformations of metal adsorption isotherms suggested differences in the mechanisms involved in metal uptake by the various yeasts. The differences between strains ofS. cerevisiae were due possibly to differences in cell wal composition. Different methods of preparation of biomass (fresh, air, oven and freeze-dried) had little effect on metal uptake in comparison with fresh biomass. Storage of fresh waste biomass at 4°C for 20 days had no effect on metal biosorption capacities. It was also observed that individual batches of waste biomass produced from different fermentation runs had consistent metal uptake capacities. The implications of the above results on the use of waste yeast biomass for treatment of metal-containing effluents are discussed.; Simmons...

Protein detection and quantitation technologies for gel-based proteome analysis

Weiss, W.; Weiland, F.; Luck, C.
Fonte: Humana Press, Inc. Publicador: Humana Press, Inc.
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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Numerous protein detection and quantitation methods for gel-based proteomics have been devised that can be classified in three major categories: (1) Universal (or "general") detection techniques, which include staining with anionic dyes (e.g., Coomassie brilliant blue), reverse (or "negative") staining with metal cations (e.g., imidazole-zinc), silver staining, fluorescent staining or labeling, and radiolabeling, (2) specific staining methods for the detection of post-translational modifications (e.g., glycosylation or phosphorylation), and (3) differential display techniques for the separation of multiple, covalently tagged samples in a single two-dimensional electrophoresis (2-DE) gel, followed by consecutive and independent visualization of these proteins to minimize methodical variations in spot positions and in protein abundance, to simplify image analysis, as well as to improve protein quantitation by including an internal standard.The most important properties of protein detection methods applied in proteome analysis include high sensitivity (i.e., low detection limit), wide linear dynamic range for quantitative accuracy, reproducibility, cost-efficiency, ease of use, and compatibility with downstream protein identification or characterization technologies...

Multielemental analysis of dried residue from metal-bearing waters by wavelength dispersive X-ray fluorescence spectrometry

González-Fernández, Oscar; Marguí, Eva; Queralt Mitjans, Ignacio
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 270754 bytes; application/pdf
ENG
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The purpose of this work was evaluation of instrumental sensitivity and detection limits for determination of elemental composition (20 different elements ranging from Na to Pb) of liquid mining samples by using conventional Wavelength Dispersive X-Ray Fluorescence (WDXRF) instrumentation. Preconcentration of elements from liquid samples was performed by means of a simple dried residue process, and spectral evaluation was carried out by integration of the peak area (using WinQXAS/AXIL package software, International Atomic Energy Agency (IAEA)) instead of the common net peak line intensity traditionally used in conventional WDXRF systems. With the proposed methodology, the calculated detection limits were in the µg L− 1 range (from 0.005 to 0.1 mg L− 1 level depending on the element) in all cases, which is suitable for element determination in most liquid samples involved in environmental studies such as metal mining liquid effluents. The detection limits are also below the established limits of the TCLP 1311 (United States Environmental Protection Agency (US-EPA)) and DIN 38414-S4 (German Standard legislation) procedures, which are commonly used to evaluate the leaching of metals from landfill disposal. Accuracy of the procedure was confirmed by analysis...

Espectroscopía vibracional sobre nanoestructuras metálicas (SERS y SEIR): nuevos sustratos y aplicaciones; Vibrational spectroscopy on metal nanostructures (SERS and SEIR): new substrates and applications

García-Ramos, José Vicente; Sánchez-Cortés, Santiago
Fonte: Sociedad Española de Óptica Publicador: Sociedad Española de Óptica
Tipo: Artículo Formato: 253177 bytes; application/pdf
SPA
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[EN] This work summarises the researching activity carried out in our group, placed in the Institute of the Matter Structure, on the following researching lines: a) Preparation of nanostructured metallic surfaces with potential applications in nanostructure-enhanced vibrational spectroscopy, mainly SERS and SEIR; b) Characterisation of the above surfaces by spectroscopic and microscopic methods; c) Functionalisation of such nanostructured surfaces by highly specific molecules able to be self-assembled on the surface; and, finally, d) application of these surfaces (metal-host) to the study and detection of ligands with environmental and/or biological interest. In this work, examples of these applications are shown for the case of the detection of PAHs (Polycyclic Aromatic Hydrocarbons) by means of calixarene host molecules, and the interaction study of emodin drug with human serum albumin.; [ES] El trabajo presentado constituye un resumen de la labor investigadora llevada a cabo en nuestro grupo, en el Instituto de Estructura de la Materia sobre las líneas de investigación siguientes: a) Preparación de superficies metálicas nanoestructuradas con aplicaciones en espectroscopías vibracionales intensificadas por nanoestructuras...

Noves aportacions a l'estudi de la capacitat coordinant de les metal·lotioneïnes el catió Ag(I) com a substitut de Cu(I) en les Cu(I)-MT i l'espectrometria de masses (ESI-MS) com a tècnica essencial i complementària a l'espectroscòpia òptica /

Palacios Bonilla, Òscar
Fonte: Bellaterra : Universitat Autònoma de Barcelona, Publicador: Bellaterra : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf; application/pdf
Publicado em //2004 CAT; CAT
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Consultable des del TDX; Títol obtingut de la portada digitalitzada; Les metalotioneïnes (MT) són unes proteïnes de baix pes molecular i elevat contingut en residus de cisteïna que es caracteritzen per la seva extremada habilitat para enllaçar tant cations de metalls essencials, com Zn(II) i Cu(I), com de metalls tòxics (Cd(II), Hg(II)). En una primera part d'aquest treball s'analitza la utilització del catió Ag(I) com a sonda del catió Cu(I) en l'estudi de les Cu-MT, i en conseqüència es compara detalladament el comportament d'ambdós metalls enfront la isoforma 1 de MT de mamífer. Aquesta proteïna, així com els seus fragments constitutius a i b, s'ha obtingut per enginyeria genètica amb la finalitat d'assegurar al màxim el seu grau de puresa. L'estudi de la capacitat coordinant de MT 1, aMT 1 i bMT 1 enfront Ag(I) s'ha dut a terme mitjançant tècniques d'espectroscòpia electrònica (CD i UV-Vis) i de masses (ESI-MS). Aquesta darrera tècnica ha requerit la incorporació d'un mètode de separació previ a la determinació de la massa, per tal d'eliminar la presència de tampó a la mostra. L'electroforesi capil·lar (CZE) acoblada a l'ESI-MS ha demostrat ser una bona opció. Amb la finalitat de validar l'acoblament CZE-ESI-MS...

Ultrasensitive mass sensor fully integrated with complementary metal-oxide-semiconductor circuitry

Forsen, E.; Abadal Berini, Gabriel; Ghatnekar-Nilsson, S.; Teva Meroño, Jordi; Verd Martorell, Jaume; Sandberg, R.; Svendsen, W.; Pérez Murano, Francesc; Esteve Tinto, Jaume; Figueras Costa, Eduardo; Campabadal Segura, Francesca; Montelius, L.; Barniol
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2005 ENG
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Nanomechanical resonators have been monolithically integrated on preprocessed complementary metal-oxide-semiconductor(CMOS) chips. Fabricatedresonatorsystems have been designed to have resonance frequencies up to 1.5 MHz. The systems have been characterized in ambient air and vacuum conditions and display ultrasensitive mass detection in air. A mass sensitivity of 4ag/Hz has been determined in air by placing a single glycerine drop, having a measured weight of 57 fg, at the apex of a cantilever and subsequently measuring a frequency shift of 14.8 kHz. CMOS integration enables electrostatic excitation, capacitive detection, and amplification of the resonance signal directly on the chip.

Aprofundiment en la relació estructura/funció de diverses metal·lotioneïnes (MTs) per analitzar els factors que determinen la seva especificitat metàl·lica

Pérez Rafael, Sílvia
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf; application/pdf
Publicado em //2014 CAT
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La tasca investigadora realitzada, i recollida en la present Tesi Doctoral, és el resultat de l'estudi i caracterització de l'especificitat metàl·lica, vers Zn(II), Cu(I) i Cd(II), de diferents metal·lotioneïnes i de l'anàlisi dels factors que poden determinar aquesta especificitat. El conjunt de proteïnes estudiades el componen principalment isoformes d'MTs de mol·luscs: els cargols terrestres H.pomatia i C.aspersum i el barretet marí M.crenulata. L'estudi de les propietats coordinants d'aquestes proteïnes ha fet possible establir l'existència, en els dos cargols, d'una isoforma d'MT amb una clara preferència per Cd(II) i d'altres per Cu(I), podent relacionar aquest comportament amb el rol fisiològic d'aquestes proteïnes (destoxicació de cadmi i homeòstasi de coure, respectivament). En canvi, M.crenulata té una única MT, McMT, que no presenta una clara especificitat per Zn(II), Cd(II) o Cu(I), podent participar en ambdós tipus de processos fisiològics. L'estudi conjunt de les diferents MTs ha permès concloure que proteïnes similars (contingut en cisteïnes i la seva posició relativa dins la cadena peptídica) poden presentar especificitats metàl·liques molt diferents, sent els aminoàcids no coordinants els responsables d'aquesta diversitat. S'han estudiat també altres MTs: de B.floridae (amfiox) i de D.melanogaster (mosca). L'amfiox...

Surface structuration of metal-organic frameworks using tip-based lithographies

Carbonell Fernández, Carlos; Pascual Gaínza, Jordi
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2015 ENG
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La presente Tesis Doctoral se ha dedicado al estudio, desarrollo e implementación de métodos para la síntesis y micro- nanoestructuración de materiales metal-orgánicos porosos (MOFs, Metal-Organic Frameworks) sobre superficies. La importancia en la estructuración de MOFs con alta resolución radica en la necesidad de su integración en microdispositivos, especialmente de tipo sensor. En el primer capítulo se realiza una prospección bibliográfica sobre el estado del arte en MOFs, con una breve introducción histórica, las principales rutas sintéticas, propiedades y aplicaciones. Se introducen también los nano-MOFs (NMOFs) con sus particularidades tanto sintéticas como relativas a sus propiedades y aplicaciones. Este capítulo incluye el trabajo de revisión titulado "Nanoscale Metal-Organic Materials", Chemical Society Reviews (2010) donde se da una descripción extensa y más genérica sobre materiales Metal-Orgánicos. El Capítulo 2 cita los objetivos generales y particulares de la presente Tesis Doctoral. En el Capítulo 3 se introduce la nanoestructuración de MOFs en superficie y se desarrolla un nuevo método para nanoestructurar un MOF en particular (HKUST-1) sobre superficies con precisión nanométrica y al nivel de monocristales. Además de desarrollar un nuevo y versátil método para nanoestructurar HKUST-1 en superficies...

Bismuth based (nano)materials and platforms for (bio)sensing

Cadevall Riera, Miquel
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2015 ENG
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La tesi està basada en la fabricació de nous sensors i biosensors per a la detecció de contaminants. Els micro i nanomateials basats en bismut semblen ser materials molt apropiats per aconseguir aquest objectiu, tanmateix també s'han proposat altres plataformes sensores. En el primer capítol es descriuen detalladament els principals objectius d'aquesta tesi. La introducció d'aquesta tesi descriu les aplicacions més recents i rellevants basades en la utilització de nanomaterials de bismut, com ara en els camps de la medicina, la fotodegradació de contaminants orgànics, la cosmètica, els pigments o els aliatges. Aquesta part precedeix la descripció dels mètodes de síntesi més innovadors, dels sensors més eficients, bàsicament de metalls pesants, i de les aplicacions en el camp dels biosensors. Aquest recull es pot trobar al capítol 2. Les nanopartícules de bismut són una bona plataforma per a sensors i biosensors. En aquest sentit s'ha estudiat la modificació d'elèctrodes serigrafiats amb nanopartícules de bismut. En el capítol 3, s'avaluen diferents mètodes de síntesi de nanopartícules de bismut amb l'objectiu d'obtenir les nanopartícules més eficients en la detecció de metalls pesants; en aquest cas centrat en la detecció de cadmi i plom. Al capítol 4 es presenta una nova estratègia de modificació d'elèctrodes. Aquesta estratègia es basa en la utilització de nanopartícules core-shell. Tenint en compte l'avantatge que dóna el recobriment de bismut...