Qcm
Mostrando 13-24 de 27 artigos, teses e dissertações.
-
13. Influência da temperatura e de aditivos na matriz fosfolipídica usada para incorporação de fosfatases alcalinas pela técnica de Langmuir-Blodgett / Influence of the temperature and adtives in phospholipidic matrix utilized to Alkaline Phosphatases incorporation by Langmuir-Blodgett tecnique
ABSTRACT Alkaline phosphatases (AP) are unspecific enzymes that hydrolyze phosphate esthers. In this Dissertation we have studied the adsorption of two forms of AP in phospholipid Langmuir monolayers and Langmuir-Blodgett films, considered as biomembrane models, at different temperatures. Further, the effect of the presence of a disaccharide, trehalose, as w
Publicado em: 2007
-
14. Production of selective membranes using plasma deposited nanochanneled thin films
The hydrolization of thin films obtained by tetraethoxysilane plasma polymerization results in the formation of a nanochanneled silicone like structure that could be useful for the production of selective membranes. Therefore, the aim of this work is to test the permeation properties of hydrolyzed thin films. The films were tested for: 1) permeation of polar
Materials Research. Publicado em: 2006-12
-
15. Preparation of an estuarine sediment quality control material for the determination of trace metals
Os materiais de controle de qualidade (QCM) têm sido usados rotineiramente no trabalho de laboratório, para preencher a lacuna entre a necessidade e disponibilidade de materiais de referência certificados (CRM). Os QCMs possuem custos relativamente baixos, quando comparados aos materiais de referência certificados (CRMs), sendo uma alternativa viável pa
Journal of the Brazilian Chemical Society. Publicado em: 2006-04
-
16. Preconcentration in gas or liquid phases using adsorbent thin films
The possibility of preconcentration on microchannels for organic compounds in gas or liquid phases was evaluated. Microstructures with different geometries were mechanically machined using poly(methyl methacrylate) - PMMA as substrates and some cavities were covered with cellulose. The surfaces of the microchannels were modified by plasma deposition of hydro
Materials Research. Publicado em: 2006-03
-
17. Aplicação da ressonancia de plasmon de superficie e da microbalança de cristal de quartzo na investigação de processos interfaciais visando o desenvolvimento de sensores / Applications of surface plasmon resonance and quartz crystal microbalance in the investigation of interface processes intending the sensors development
The present work describes the applications of surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) in the investigation of interface processes in the attempt to improve the understanding and application of the investigated systems as well as the establishment of the applications of the SPR allied with electrochemical techniques. In this sen
Publicado em: 2006
-
18. Estudo eletroquÃmico da adsorÃÃo de molÃculas organosulfuradas sobre superfÃcie de ouro. / Electrochemical study of the adsorÃÃo of moleculas organosulfuradas on gold surface.
Modified gold surface with organosulfur species, 1,4-dithiane (1,4-dt) and 4- mercaptopyridine (pyS), was studied in this work. The study was carried out using the following electrochemical techniques: linear polarization with rotate disk electrode, cyclic voltammetry, differential pulse voltammetry, electrohydrodynamic impedance and electrochemical impedanc
Publicado em: 2006
-
19. Electroacoustic Admittance/ Impedance Applied to the Study of Self-Assembled Monolayers Formation and to the Study of Protein-Carbohydrate Affinity / Admitância/impedância eletroacústica aplicada ao estudo da formação de monocamadas automontadas e da afinidade proteínas/carboidratos
A técnica de Microbalança de Cristal de Quartzo (QCM) tem sido utilizada para a aplicação em biossensores. Esta técnica consiste no monitoramento da freqüência de oscilação do cristal de quartzo e a variação de freqüência está relacionada com a variação de massa na superfície do cristal por meio da equação de Sauerbrey. Porém, sabe-se que
Publicado em: 2006
-
20. Desenvolvimento de equipamento de teste de estruturas miniaturizadas: testes em estrutura útil na eliminação de partículas. / Development of machine to test miniaturized structures: tests in util structure from particles elimination.
Samples with small volume and complex matrix, such as biological systems, require careful preparation. Many of these samples are better analyzed in miniaturized structures owing to the need of detect cells and microorganisms in different arrays. Therefore equipment able to detect and destroy microorganisms and structures to previously retain them are require
Publicado em: 2006
-
21. Aplicações de QCM, EIS e SPR na investigação de superfícies e interfaces para o desenvolvimento de (bio)sensores
The use of the quartz crystal microbalance process, electrochemical impedance spectroscopy and surface plasmon resonance for characterizing thin films and monitoring interfaces is presented. The theorical aspects of QCM, EIS and SPR are introduced and the main application areas are outlined. Future prospects of the combined applications of QCM, EIS and SPR m
Química Nova. Publicado em: 2004-12
-
22. Study of charge and mass transference on copper/liquid interface : an application of QCM / Estudo da transferencia de carga e massa na inteface cobre/liquido : uma aplicação da QCM
In this work we used the QCM (Quartz Crystal Microbalance) as an alternative technique for the studying of the corrosion/inhibition of cooper. We studied the protection of cooper surfaces due to the adsorption of a volatile corrosion inhibitor, (VCI-Cyclehexilamine-Benzoate). We used electrochemical techniques to characterize the corrosion in different envir
Publicado em: 2004
-
23. Desenvolvimento de biossensores eletroquÃmico e piezelÃtrico de dna para diagnÃsticos clÃnicos / Desenvolvimento de biossensores eletroquÃmico e piezelÃtrico de dna para diagnÃsticos clÃnicos
No mundo investimento para o desenvolvimento de novos mÃtodos de diagnÃstico genÃtico e de doenÃas infecciosas tem se tornado muito freqÃente. Biossensores de DNA (genossensores) aparecem como uma nova e eficiente alternativa, com boa sensibilidade e baixo custo. Neste trabalho, o desenvolvimento de novos suportes alternativos para imobilizaÃÃo de Ãc
Publicado em: 2004
-
24. Zinc oxide films doped with aluminium or europium: preparation and characterization. / Filmes de óxido de zinco dopado com alumínio ou európio: preparação e caracterização.
The interest in the preparation of thin films by the sol-gel process has increased in last years due to the high quality of the films, low cost of the organic precursors and the great technological importance. Depending on the preparation conditions and dopant species, it is possible to obtain films with piezelectric, luminescent, isolating, conductive and s
Publicado em: 2001