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Determinação espectofométrica de hipoclorito em alvejantes e cloro em águas de abastecimento empregando sistema em fluxo por multicomutação e células convencional e de longo caminho óptico
(Universidade Federal de São Carlos, 2008-02-18) Salami, Fernanda Helena; Fatibello Filho, Orlando; https://lattes.cnpq.br/9859737944357808; https://lattes.cnpq.br/6112526858589406
A multicommutation flow system for the spectrophotometric determination of hypochlorite in bleaching products using a cell with pathlength of 1 cm is proposed in this work. In this system, N,N-diethyl-p-phenylenediamine (DPD) reacts with hypochlorite and the product was monitored at 515 nm. The analytical curve for hypochlorite was linear in concentration range from 2.68x10-5 to 1.88x10-4 mol L-1 (2 to 14 mg L-1) with a detection limit of 6.84x10-6 mol L-1 (0.51 mg L-1). The sampling rate of 45 h-1 and a relative standard deviation of 1.4 % (n = 10), were obtained. The recovery of this analyte ranged from 97% to 102.5%. The results found for six bleaching products using the proposed multicommutated flow system agreed with those data obtained using a reference method (iodometric titration) at the 95 % confidence level. A multicommutation flow system for the spectrophotometric determination of chlorine in water samples using a cell with 100 cm of pathlength is also proposed in this work. In this system, dichloridrate orto-Tolidine (3,3-dimethyl bencidine) reacts with chlorine and the product was monitored at 438 nm. The analytical curve for hypochlorite was linear in the concentration range from 1.34x10-6 to 2.01x10-5 mol L-1 (0.1 to 1.5 mg L-1) with a detection limit of 9.4x10-8 mol L-1 (7.0x10-3 mg L-1). The sampling rate of 45 h-1 and a relative standard deviation of 1.0 % (n = 15), were obtained. The recovery of this analyte ranged from 96.8% to 104.6%. The results found for six water samples from São Carlos city using the proposed method agreed with those data obtained using the method used by CETESB (Kit DPD colorimetric) at the 95 % confidence level. The long pathlength optic system is composed by amorphous fluorpolymeric Teflon AF2400tube with a 100 cm of length and refraction index smaller than the water one that was used as wave guide, aiming to minimize radiation losses. Finally, flow system involving multicommutation was developed to increase analytical features, decrease the reagents consumption and residual production.
Entre a proposta e o pretexto da qualidade do ensino: uma leitura sobre os liames da valorização docente a partir do FUNDEF
(Universidade Federal de São Carlos, 2008-02-18) Ramos, Géssica Priscila; Zuin, Antônio Álvaro Soares; https://lattes.cnpq.br/5543562307373287; https://lattes.cnpq.br/2573340489166336
This research purpose is to verify the relation established between teacher valorization and educational quality in the FUNDEF creation bases and in the São Paulo state and municipal implantation, analyzing how this relationship reflects the teacher's valorization. This research is based on interviews and bibliographic, documented and speaking analysis, having Gramsci as main reference. In the Fernando Henrique Cardoso government the teacher was considered the major educational quality agent. However, this same government reduced the educational investments, according to the established goals to achieve the State Reform, impacting directly in the educational quality and teacher s valorization. In the São Paulo State, based on its ample Federal Government politic relationship, despite of its intense changes in the São Paulo pedagogic-organizational model, its initiative wasn t followed proportionally by the financials investments according to the expected, explaining the speech increasing performed between the teacher s valorization and educational quality. Related to the municipal research, this instance was limited to follow the Federal and the São Paulo State directions based on its inexperienced administrative skills in the educational area, reproducing insufficient teacher s valorization actions, under the idea to achieve local educational quality. Thus, in spite of the teacher to have your role officially outstanding in the period, less and less the educational resolution problems were approached in political-financial performance terms of the Union, of States and of the Municipal districts. This discussion was transposed strictly for a pedagogic and educational ambit, of the teacher's responsibility, and the teacher's valorization, linked to the meritocratic principles, becoming ideologically the bad or good educational quality reason, and not part of this process. Key-words: teacher valorization, educational quality, FUNDEF; educational politics; decade of 90