Application of chemometric methods in the evaluation of chemical and spectroscopic data on organic matter from Oxisols in sewage sludge applications

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Egg quality during storage and deposition of minerals in eggs from quails fed diets supplemented with organic selenium, zinc and manganese

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mechanism of anticlastogenicity of Agaricus blazei Murill mushroom organic extracts in wild type CHO (K-1) and repair deficient (xrs5) cells by chromosome aberration and sister chromatid exchange assays

Agaricus blazei Murill is a medicinal mushroom native to Brazil. The present work assessed the clastogenic and anticlastogenic potential of organic extracts (ethanol and chloroform/methanol) from the lineage AB97/11 in chinese hamster CHO-K-1 (wild type) and CHO-xrs5 (repair deficient) cells using the chromosome aberration (CA) and sister chromatid exchange (SCE) assays. In these experimental conditions were observed: (a) anticlastogenic effect at concentrations of 0.06 and 0.09% of the EtOH extract and at the 0.03 and 0.06% concentrations of the C/MetOH extract in CHO-K-1; (b) absence of protector effect on CHO-xrs5 cells; and (c) absence of protector effect in the SCE assay. These results indicate that organic extracts of A. blazei lineage AB97/11 present bio-antimutagenic type protective activity. (C) 2003 Elsevier B.V. B.V. All rights reserved.

MYCELIAL DEVELOPMENT of Lentinula edodes IN CULTURE MEDIA WITH DIFFERENT ORGANIC SUBSTRATES

The radial mycelial growth of Lentinula edodes (Berk) Pegler, strain LE-96/13, was studied in culture media prepared with organic residues extract, by using substrates prepared with pineapple (Ananas comosus (L.) Merril) crown, Astrocaryum aculeatum Meyer peel, Theobroma grandiflorum Schum shell, Musa sp. (genomic group AAB, subgroup Pacovan) peel, and Musa sp. (genomic group AAB, subgroup Praia) peel, with three supplementation levels with wheat bran (0, 10 and 20%), and incubated at 25 degrees C. The experimental design was totally randomized, in a 5x3 factorial scheme, adding up 15 treatments with 4 repetitions, and each repetition corresponding to a Petri dish. The diameter of the colony was evaluated daily during nine days of incubation. After that period, it was verified that the highest mycelial growth averages of strain LE-96/13 of L. edodes were found in culture media prepared with T. grandiflorum Schum shell (whose supplementation with wheat bran was favorable for Mushroom development) and A. aculeatum Meyer peel (whose supplementation did not favor the mycelial growth of L. edodes in relation to the medium not supplemented).

Organic compounds from plant extracts and their effect on soil phosphorus availability

O objetivo deste trabalho foi avaliar o efeito de compostos orgânicos de extratos de plantas de seis espécies e da fertilização fosfatada na disponibilidade de fósforo no solo. Tubos de 30 cm de altura e 5 cm de diâmetro foram preenchidos com Latossolo Vermelho-Amarelo. Cada tubo constituiu uma parcela, em delineamento completamente casualizado, em arranjo fatorial 7x2, com quatro repetições. Extratos líquidos de aveia-preta (Avena strigosa), nabo forrageiro (Raphanus sativus), milho (Zea mays), milheto (Pennisetum glaucum), soja (Glycine max), sorgo forrageiro (Sorghum bicolor) e água (testemunha) foram aplicados em cada parcela, com ou sem fertilização com fosfato solúvel. Após sete dias de incubação, amostras de solo foram coletadas em várias profundidades, e foram analisadas as formas lábil, moderadamente lábil e não lábil de fósforo no solo. Houve acúmulo de fósforo inorgânico nas frações lábil e moderadamente lábil do solo, como conseqüência da adição dos extratos de plantas, principalmente na camada superficial (0-5 cm). O nabo forrageiro, com maior concentração de ácido málico e maior conteúdo de P no tecido do que outras espécies, foi o mais eficiente em incrementar a disponibilidade de P no solo.

Longitudinal distribution and seasonality of macroalgae in a subtropical stream impacted by organic pollution

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Separating interface state response from parasitic effects in conductance measurements on organic metal-insulator-semiconductor capacitors

A simple model is developed for the admittance of a metal-insulator-semiconductor (MIS) capacitor which includes the effect of a guard ring surrounding the Ohmic contact to the semiconductor. The model predicts most of the features observed in a MIS capacitor fabricated using regioregular poly(3-hexylthiophene) as the active semiconductor and polysilsesquioxane as the gate insulator. In particular, it shows that when the capacitor is driven into accumulation, the parasitic transistor formed by the guard ring and Ohmic contact can give rise to an additional feature in the admittance-voltage plot that could be mistaken for interface states. When this artifact and underlying losses in the bulk semiconductor are accounted for, the remaining experimental feature, a peak in the loss-voltage plot when the capacitor is in depletion, is identified as an interface (or near interface) state of density of similar to 4 x 10(10) cm(-2) eV(-1). Application of the model shows that exposure of a vacuum-annealed device to laboratory air produces a rapid change in the doping density in the channel region of the parasitic transistor but only slow changes in the bulk semiconductor covered by the gold Ohmic contact. (C) 2008 American Institute of Physics.

Electrical characterization of poly(amide-imide) for application in organic field effect devices

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Volatile compounds from organic and conventional passion fruit (Passiflora edulis F. Flavicarpa) pulp

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Magnetic field effects on the conductivity of organic bipolar and unipolar devices at room temperature

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Impedance of carrier injection at the metal-organic interface mediated by surface states in electron-only tris(8-hydroxyquinoline) aluminium (Alq(3)) thin layers

Capacitance spectra of thin (< 200 nm) Alq(3) electron-only devices have been measured as a function of bias voltage. Capacitance spectra exhibit a flat response at high frequencies (> 10(3) Hz) and no feature related to the carrier transit time is observed. Toward low frequencies the spectra reach a maximum and develop a negative excess capacitance. Capacitance response along with current-voltage (J-V) characteristics are interpreted in terms of the injection of electrons mediated by surface states at the metal organic interface. A detailed model for the impedance of the injection process is provided that highlights the role of the filling/releasing kinetics of energetically distributed interface states. This approach connects the whole capacitance spectra to the occupancy of interface states, with no additional information about bulk trap levels. Simulations based on the model allow to derive the density of interface states effectively intervening in the carrier injection (similar to 1.5 x 10(12) cm (2)). (C) 2008 Elsevier B.V. All rights reserved.

Changing inter-molecular spin-orbital coupling for generating magnetic field effects in phosphorescent organic semiconductors

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Growing Impact of Niobium in Organic Synthesis and Catalysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Preparation, characterization, and CuX2 and CoX2 (X = Cl-, Br-, ClO4-) adsorption behavior of a polyhedral oligomer silsesquioxane functionalized with an organic base

In this paper we report on the synthesis, characterization, and adsorption properties of the first 3-amino-1,2,4-triazole-modified porous silsesquioxane (ATPS). The isotherms of adsorption of MX2 (M = Cu(II), Co(II); X = Cl-, Br-, ClO4-) by ATPS were studied in ethanol and aqueous solutions at 298 K. The results showed that there is a good fit between the experimental data and the Langmuir isotherm. The adsorption capacity in both solvents followed the sequence Cu(II) >> Co(II). The lowest adsorption for Co(II) should be related to the largest hydration volume, which obstructs the adsorption capacity of the surface, and consequently causes a decrease in the number of cations adsorbed. For the salts with different anions the sequence was MCl2 > MBr2 > M(ClO4)2 in both solvents. The low affinity for M(ClO4)(2) toward the solid phase is a consequence of the poorer coordination ability of the ClO4-. Adsorptions from ethanol solutions were higher than those from aqueous solutions due to the higher polarity of water, which can more strongly solvate the solute and the basic sites on the surface. The following adsorption capacities (in mmol g(-1)) were determined: 0.24 (aq) and 0.84 (eth) for CuCl2, 0.09 (aq) and 0.16 (eth) for CuBr2, and 0.08 (aq) and 0.11 (eth) for Cu(ClO4)(2); 0.02 (aq) and 0.07 (eth) for CoCl2, 0.02 (aq) and 0.06 (eth) for CoBr2, and 0.01 (aq) and 0.05 (eth) for Co(ClO4)(2). (c) 2007 Elsevier B.V. All rights reserved.

Bacterial cellulose-silica organic-inorganic hybrids

Bacterial cellulose (BC) hydrated membranes present nanometric reticulated structure that can be used as a template in the preparation of new organic-inorganic hybrids. BC-silica hybrids were prepared from BC membranes and tetraethoxysilane, (TEOS) at neutral pH conditions at room temperature. Macroscopically homogeneous membranes were obtained containing up to 66 wt.% of silica spheres, 20-30 nm diameter. Scanning electron micrographs clearly show the silica spheres attached to cellulose microfibrils. By removing the cellulose, the silica spheres can be easily recovered. The new hybrids are stable up to 300 degrees C and display a broad emission band under UV excitation assigned to oxygen-related defects at the silica particles surface. Emission color can be tuned by changing the excitation wavelength.