"Quattro (Rev 2018)": para quatro percussionistas e eletrónica em tempo real

A Peça Quattro, encomenda da OSN-RAI/Centro Tempo Reale, foi estreada em Turin (Festival RAI Nuova Musica 2005) pelo Gruppo di percussioni OSN RAI, sob a direcção de Pierre-André Valade. Quattro é uma peça escrita em quatro andamentos, ligados entre si, sem interrupção. A escrita de cada andamento dá especial atenção a um tipo (ou família) de instrumentos, procurando cada andamento caracterizar uma atmosfera diferente. Para mim, serviu a analogia das quatro estações (Inverno, Primavera,Verão e Outono). O grupo de quatro percussionistas funciona como um único "instrumento", que se distribui pelos instrumentistas, pelo palco e pelo espaço. A electrónica, toda ela construída sobre sons de percussão, é um segundo instrumento que comenta o primeiro. É, no fundo, como se se tratasse de uma lupa, que amplia os gestos instrumentais dos quatro músicos em termos de volume sonoro, distribuição espacial e virtuosismo. Instrumentação: 4 percussionistas e electrónica em tempo real.Revisão de Obra estreada em 2004, na qual foi totalmente redesenhado o programa informático de controlo da electrónica em tempo real. Este programa, para além de incluir o software IRIN numa abordagem de Tempo Real, contrariando a sua natureza original de software de composição em tempo diferido, faz uso de ferramentas desenvolvidas no âmbito do Projecto Laboratório de Música Mista (IDI&CA - Projetos de Investigação, Desenvolvimento e Criação Artística do Instituto Politécnico de Lisboa).info:eu-repo/semantics/publishedVersio

Rapid Method For The Determination Of Organic Acids In Wine By Capillary Electrophoresis With Indirect Uv Detection

A capillary electrophoresis method for organic acids in wine was developed and validated. The optimal electrolyte consisted of 10 mmol/L 3,5-dinitrobenzoic acid (DNB) at pH 3.6 containing 0.2 mmol/L cetyltrimethylammonium bromide as flow reverser. DNB was chosen because it has an effective mobility similar to the organic acids under investigation, good buffering capacity at pH 3.6, and good chromophoric characteristics for indirect UV-absorbance detection at 254 nm. Sample preparation involved dilution and filtration. The method showed good performance characteristics: Linearity at 6 to 285 mg/L (r > 0.99); detection and quantification limits of 0.64 to 1.55 and 2.12 to 5.15 mg/L, respectively; separation time of less than 5.5 min. Coefficients of variation for ten injections were less than 5% and recoveries varied from 95% to 102%. Application to 23 samples of Brazilian wine confirmed good repeatability and demonstrated wide variation in the organic acid concentrations. © 2008 Elsevier Ltd. All rights reserved.206548552Arellano, M., Andrianary, J., Dedieu, F., Couderc, F., Puig, P., Method development and validation for the simultaneous determination of organic acid and inorganic acids by capillary zone electrophoresis (1997) Journal of Chromatography A, 765, pp. 321-328Arellano, M., Couderc, F., Puig, P.H., Simultaneous separation of organic and inorganic acids by capillary zone electrophoresis. Application to wines and fruit juices (1997) American Journal of Enology and Viticulture, 48, pp. 408-412Bianchi, F., Careri, M., Corradini, C., Novel approach for the rapid determination of water-soluble organic acids in wine by co-electroosmotic flow capillary zone electrophoresis (2005) Journal of Separation Science, 28, pp. 898-904Castiñeira, A., Peña, R.M., Herrero, C., García-Martín, S., Simultaneous determination of organic acids in wine samples by capillary electrophoresis and UV detection: Optimization with five different background electrolytes (2000) HRC - Journal of High Resolution Chromatography, 23, pp. 647-652Castiñeira, A., Peña, R.M., Herrero, C., García-Martín, S., Analysis of organic acids in wine by capillary electrophoresis with direct UV detection (2002) Journal of Food Composition and Analysis, 15, pp. 319-331De Villiers, A., Lynen, F., Crouch, A., Sandra, P., A robust capillary electrophoresis method for the determination of organic acids in wines (2003) European Food Research and Technology, 217, pp. 535-540Esteves, V.I., Lima, S.S.F., Lima, D.L.D., Duarte, A.C., Using capillary electrophoresis for the determination of organic acids in Port wine (2004) Analytica Chimica Acta, 5131, pp. 163-167García Moreno, M.V., Jurado Campoy, C.J., García Barroso, C., Method devised for determining low molecular weight organic acids in vinic samples by capillary electrophoresis: Validation of the method with real samples (2001) European Food Research and Technology, 213, pp. 381-385Hirokawa, T., Nishino, M., Aoki, N., Kiso, Y., Table of isotacophoretic indices I. Simulating qualitative indices of 287 anionic substances in the range pH 3-10 (1983) Journal of Chromatography, 271, pp. D1-D106Kandl, T., Kupina, S., An improved capillary electrophoresis procedure for the determination of organic acids in grape juice and wine (1999) American Journal of Enology and Viticulture, 50, pp. 155-161Kelly, L., Nelson, R.J., Capillary zone electrophoresis of organic acids and anions (1993) Journal of Liquid Chromatography and Related Technologies, 16, pp. 2103-2112Kenney, B.F., Determination of organic acids in food samples by capillary electrophoresis (1991) Journal of Chromatography A, 546, pp. 423-430Klampfl, C.W., Katzmayr, M.U., Buchberger, W., Separation of inorganic and organic anions by capillary zone electrophoresis with simultaneous indirect UV and conductivity detection (1998) Electrophoresis, 19, pp. 2459-2464(2007) Handbook of capillary and microchip electrophoresis and associated microtechniques. 3rd ed., , Landers J.P. (Ed), CRC Press Inc, Boca RatonLevi, V., Wehr, T., Talmadge, K., Zhu, M., Analysis of organic acids in wines by capillary electrophoresis and HPLC (1993) American Laboratory, 25, pp. 29-32Mato, I., Suárez-Luque, S., Huidobro, J.F., Simple determination of main organic acid in grape juice and wine by using capillary zone electrophoresis with direct UV detection (2007) Food Chemistry, 102, pp. 104-112Moreno, M.V.G., Jurado, C.J., Barroso, C.G., Determination of organic acids by capillary electrophoresis with simultaneous addition of Ca and Mg as complexing agents (2003) Chromatographia, 57, pp. 185-189Ribereau-Gayon, P., Gloris, Y., Maujean, A., Dubourdieu, D., (2000) Handbook of enology, The chemistry of wine, stabilization and treatments, 2. , Wiley, New YorkSaavedra, L., Barbas, C., Validated capillary electrophoresis method for small-anions measurement in wines (2003) Electrophoresis, 24, pp. 2235-2243Sing Fung, Y., Man Lau, K., Analysis of organic acids and inorganic anions in beverage drinks by capillary electrophoresis (2003) Electrophoresis, 24, pp. 3224-3232Stathakis, C., Cassidy, R.M., Effect of electrolyte composition in the capillary electrophoretic separation of inorganic/organic anions in the presence of cationic polymers (1995) Journal of Chromatography A, 699, pp. 353-361Zoecklein, B.W., Fugelsang, K.C., Gump, B.H., Nury, F.S., (1999) Wine analysis and production, , Aspen Publishers Inc, Gaithersbur