Papers by Teresa Dib Zambon Atvars
Contabilidade, Gestão e Governança/UNB Contábil, Feb 15, 2024
Objective: To analyze, based on the requirements of good public governance, the resilience of thr... more Objective: To analyze, based on the requirements of good public governance, the resilience of three public universities in the State of São Paulo (USP, Unesp, and Unicamp) in the face of future financial crises. Method: Utilizing basic principles of autonomy linked to the budget to address the role of General Comptroller's Offices (GCOs) and Internal Control Systems (ICSs) as decision-making support bodies in a governance model that uses risk analysis as strategic information. Originality/Relevance: This is the first time that a comparative analysis of pos-facto measures, based on the requirements of the good public governance has been presented for these three universities, and it concludes that these universities are at different stages of changes in governance. Results: It shows that the financial crisis experienced by these three universities has occurred due to the combination of a financial crisis in this country and an unsustainable increase in university spending without proper risk analysis. Based on the information available on open web portals, we have found that USP has effectively implemented a GCO and ICS as one of their pos-facto measures, but in general, internal corporate-political criteria still predominate in decision making regarding increased spending. Theoretical/Methodological Contributions: It demonstrates the relevance of GCOs and ICSs in the governance of public universities with autonomy and budgetary restrictions. Social/Management Contributions: The main contribution is that it demonstrates the importance of more effective interactions with external stakeholders in institutional decisions, in contrast to the current model of decision-making which is guided mainly by internal corporate/political criteria.
Spectroscopy Letters, Jun 1, 1990
Electronic absorption and fluorescence spectra of dipyridamole, a coronary vasodilator drug, were... more Electronic absorption and fluorescence spectra of dipyridamole, a coronary vasodilator drug, were monitored in aqueous solutions as a function of pH in the range between 13 and 2. The spectra were decomposed into Gaussian components and the parameters were obtained and compared both in aqueous solution at different pHs and in several other solvents. The extinction coefficients were also obtained as well as the quantum yields and fluorescence lifetimes. At pH 7.0 e 415 = (5.4 ± 0.2)x10 3,~fluor = 0.95±0.05 and Tfluor = 17.8±0.4 ns, while at pH 5.0~-(4.8±0.2)x10, d~flaor = 0.16±0.01 and 1•fluor = 5.7±0.2ns. The decrease of pH is accompanied by sharp fluorescence changes in two different regions: in the range of pH 13-12 an increase of fluorescence is observed (pK 1 12.5) while in the range of pH 6.5-5.0 a dramatic decrease of fluorescence (pK2 5.7) is apparent. Changes in the position and shape of the absorption bands are also observed in this pH range (around pK2). A Förster cycle calculation using absorption and fluorescence data shows that the pKa of the excited state is around 1 unit below pK2. Similar changes are also observed in ethanolic solution of DIP with addition of acid. They could be explained as probably due to the protonation of two types of nitrogen atoms which are part of the structure of the DIP molecule. Changing the ionic strength of the solution in the range 0-0.1M gives only a slight (10%) decrease of the fluorescence intensity and does not affect the absorption spectrum of DIP. This suggests that ionic association is not very effective in changing the spectral properties of DIP.
Journal of the Brazilian Chemical Society, 2008
As propriedades fotofísicas de um poli(metacrilato de metila) (PMMA) contendo 1,6 mol % de grupos... more As propriedades fotofísicas de um poli(metacrilato de metila) (PMMA) contendo 1,6 mol % de grupos etil-carbazolila aleatoriamente distribuídos pela cadeia, foram estudadas pelas técnicas de espectroscopia de fluorescência em condições fotoestacionárias e com resolução temporal. O material foi preparado a partir da esterificação do poli(metacrilato de metilaco-ácido metacrílico) com 9H-carbazolila-9-etanol. A temperatura ambiente, o espectro de fluorescência que se obtém para a amostra em solução é devido ao lumóforo isolado. Em filme, suas características espectroscópicas se tornam mais complexas, com contribuições do lumóforo isolado, dímeros formados no estado eletrônico fundamental e excímeros. A 77 K, a emissão obtida das amostras, tanto em filme quanto em solução, apresenta também a contribuição da fosforescência, que ocorre na mesma região espectral que a emissão de fluorescência dos agregados emissores. Os diversos tipos de relaxações mecânicas do polímero puderam ser observados através dos espectros de fluorescência do filme, obtidos na faixa de temperatura de 30 a 410 K e são similares àqueles relativos ao PMMA. Os dados obtidos por calorimetria diferencial de varredura (DSC) e análise térmica dinâmico-mecânica (DMTA) são comparados aos dados fornecidos pela espectroscopia de fluorescência e as temperaturas onde ocorrem estas relaxações puderam ser determinadas. Assim os processos da γ-relaxação, que é resultante de movimentos de pequenos segmentos de cadeia, ocorrem a 120-130 K (observados por espectroscopia de fluorescência), a β-relaxação, resultante dos movimentos de grupos éster laterais (observada por DMTA e espectroscopia de fluorescência), a 310 K e α-relaxação (temperatura de transição vítrea) ocorre a 380 K (observada por DSC e DMTA). The photophysical properties of solutions and films of poly(methyl methacrylate) (PMMA) containing 1.6 mol % of randomly distributed pendant ethyl carbazolyl groups have been studied under steady-state and time-resolved conditions. The polymer was prepared by esterification of poly(methyl methacrylate-co-methacrylic acid) by 9H-carbazole-9-ethanol. At room temperature, the steady-state fluorescence spectrum is attributed to isolated lumophores in solution, but is much more complex in films where emission is detected from isolated groups, ground-state dimers and excimers. At 77 K, emission from both solutions and films contains a component of phosphorescence whose wavelengths overlap fluorescence from excited ground-state dimers and excimers. From the temperature dependence of the steady-state emission spectra of the films, recorded from 30 to 410 K, several types of relaxation processes are identified at temperatures similar to those of unmodified PMMA. Data by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and fluorescence spectroscopy are compared. They include the γ-relaxations from motions of small segments of the chains at 120-130 K (by fluorescence spectroscopy), the β-relaxation from motions of lateral ester groups (by DMTA and fluorescence spectroscopy) at 310 K and α-relaxations (glass transition onset) at 380 K (by DSC and DMTA).
Journal of Chemical Physics, May 1, 1978
Laser photochemistry of BC1)/H 2 using catalysis was carried out experimentally. The 10.55 IJ-m r... more Laser photochemistry of BC1)/H 2 using catalysis was carried out experimentally. The 10.55 IJ-m radiation from a high power (G W Icm 2) TEA CO 2 pulse laser was used to selectively excite the llBC1) molecules. Using Ti catalyst the reaction products analyzed were lOBllBH2Cl •• IIB ll BH 2 Cl •• and HCl, whereas those were IOBIIBCI •• IIBIIBCI., and HCl when Pb metal powder was employed, i.e., IOBI~H2Cl. and IOBlOBCl. molecules were not generated in our experiment. Moreover, it was found that the IOBCl) concentration in the unreacted BCl) gas increased from 20% to 37% after 360 laser pulses. but the isotopic enrichment was not obtained for the reaction products. The mechanisms for the observed catalytic laser photochemistry are proposed.
Synthetic Metals, Feb 1, 2012
The synthesis and structural characterization of a europium complexed fluorene-bipyridine copolym... more The synthesis and structural characterization of a europium complexed fluorene-bipyridine copolymer are described. A level of ion insertion of 80% in molar basis was achieved, and theoretical calculations showed that it required a twist of 179 • (49 kJ) between the pyridine units. Spectroscopy data showed that no electronic coupling between the main backbone and the complexation sites had occurred, but these hindered the interchain aggregation observed in the non complexed polymer. Preliminary electroluminescence studies showed that the EL and PL spectra are consistent, and that the ion had a trapping effect in the charge transport.
Revista Chemkeys, Sep 17, 2018
Journal of Physical Chemistry C, Dec 15, 2014
Optical Materials, Dec 1, 2004
An investigation is made into molecular design strategies to enhance the two-photon absorption (2... more An investigation is made into molecular design strategies to enhance the two-photon absorption (2PA) of organic materials by measuring the 2PA cross-section of diazoaromatic compounds with the femtosecond pulses Z-scan technique at 775 nm. These diazo dyes exhibit a moderate 2PA cross-section, of the order of 300 GM, comparable to those of regular azoaromatic compounds. The increase in the p-electron bridge in the diazoaromatic compounds does not bring, therefore, substantial increase to the measured 2PA intensities, while the main factor to enhance the 2PA cross-section is the presence of charge donor and acceptor groups. It is concluded that current molecular design strategies are unlikely to produce azoaromatic compounds that are useful for applications requiring very high 2PA coefficients.
Macromolecular Symposia, Oct 1, 2010
In the present work, bilayered hybrids obtained by hydrosilylation of polysiloxane with carbazoly... more In the present work, bilayered hybrids obtained by hydrosilylation of polysiloxane with carbazolyl moieties (Sil-Cz) and polyfluorene (Sil-PFO) had their photophysical behavior, morphological characteristics and interaction properties studied for applications in electroluminescent devices. Fluorescence spectra of the Sil-Cz did not show emission in the excimer/aggregate region (from 400 to 500 nm). This is an unexpected behavior since most of the carbazole-based materials present excimer and aggregation. Nonetheless, this unusual observation was also predicted by geometry optimization calculations. Fluorescence spectra were taken for both compounds separately and for the bilayered system show some evidence of interaction between carbazolyl and polyfluorene moieties, giving rise to the supposition that the can form a system with tunable luminescent properties.
Revista Chemkeys, Sep 17, 2018
Spectroscopy Letters, 1980
Page 1. SPECTROSCOPY LETTERS, 13(4), 167-184 (1980) - VIBRATIONAL FREQUENCIES OF ISOTOPICALLY SUB... more Page 1. SPECTROSCOPY LETTERS, 13(4), 167-184 (1980) - VIBRATIONAL FREQUENCIES OF ISOTOPICALLY SUBSTITUTED BC13 CT Lin* and TDZ Atvars Institute dt: Quimica aiid lnstituto dt Fisica "Gleb Wataghin" Universidade ksLdual dc Crinpiiuds 13100, C.ampinns. ...
Química Nova, May 1, 2002
Recebido em 30/3/01; aceito em 12/9/01 GLASSY STATE ON THE UNDERGRADUATE COURSE IN CHEMISTRY (PHY... more Recebido em 30/3/01; aceito em 12/9/01 GLASSY STATE ON THE UNDERGRADUATE COURSE IN CHEMISTRY (PHYSICAL CHEMISTRY). We consider the relevance of the study of the glassy state properties and the glass transition as important topics of the physical chemistry for undergraduate courses of Chemistry. Two of the most important theoretical approaches for the description of the glassy state, the thermodynamic and the kinetic models, are summarized with emphasis on the physical chemistry aspects. Examples illustrating the glass transition of some materials are also presented.
Optical Materials, Oct 1, 2007
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Papers by Teresa Dib Zambon Atvars