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281.
Silva MG Vieira IG Mendes FN Albuquerque IL dos Santos RN Silva FO Morais SM 《Molecules (Basel, Switzerland)》2008,13(10):2482-2487
Ursolic acid is a very important compound due to its biological potential as an anti-inflammatory, trypanocidal, antirheumatic, antiviral, antioxidant and antitumoral agent. This study presents the HPLC analysis of ursolic acid (UA) content in eight different Ocimum species: O. americanum L., O. basilicum L, O. basilicum var purpurascens Benth, O. basilicum var. minimum L, O. gratissimum L, O. micranthum Willd, O. selloi Benth. and O. tenuiflorum L. grown in Northeastern Brazil. In these Ocimum species, UA was detected in different yields, with O. tenuiflorum showing the highest content (2.02%). This yield is very significant when compared with other sources of UA. 相似文献
282.
As is well known, a possible generalization to ?4 of the classical Cauchy–Riemann system leads to the so‐called Riesz system. The main goal of this paper is to construct explicitly a complete orthonormal system of polynomial solutions of this system with respect to a certain inner product. This will be done in the spaces of square integrable functions on the unit ball over ?. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
283.
F. E. Moura S. Prasad V. D. Leite Crislene R. S. Morais A. J. M. Barros A. G. Souza 《Journal of Thermal Analysis and Calorimetry》2007,87(3):679-683
The present
study describes the aerobic biodegradation process of a mixture of sanitary
sewage sludge and lubricating oil. TG/DTG curves confirmed that the applied
aerobic biological treatment decreased the organic material content and caused
significant modifications in the thermal behavior of the studied substrates
after the functioning period. 相似文献
284.
285.
Ariela Veloso de Paula Gisele Fátima Morais Nunes Josiane de Lourdes Silva Heizir Ferreira de Castro Júlio César dos Santos 《Applied biochemistry and biotechnology》2010,160(4):1146-1156
Seven food grade commercially available lipases were immobilized by covalent binding on polysiloxane–polyvinyl alcohol (POS-PVA)
hybrid composite and screened to mediate reactions of industrial interest. The synthesis of butyl butyrate and the interesterification
of tripalmitin with triolein were chosen as model reactions. The highest esterification activity (240.63 μM/g min) was achieved
by Candida rugosa lipase, while the highest interesterification yield (31%, in 72 h) was achieved by lipase from Rhizopus oryzae, with the production of about 15 mM of the triglycerides C50 and C52. This lipase also showed a good performance in butyl butyrate synthesis, with an esterification activity of 171.14 μM/g min.
The results demonstrated the feasibility of using lipases from C. rugosa for esterification and R. oryzae lipase for both esterification and interesterification reactions. 相似文献
286.
In this paper we give a generalization of the classical Borel–Carathéodory theorem in complex analysis to higher dimensions
in the framework of Quaternionic Analysis.
Submitted: November 14, 2007., Revised: February 25, 2008. 相似文献
287.
Marcos Roberto Monteiro Alessandra Regina Pepe Ambrozin Elisangela Fabiana Boffo Luciano Morais Lião 《Talanta》2009,78(3):660-664
In this work, the use of 1H NMR spectroscopy and statistical approach to the evaluation of biodiesel-diesel blends quality is described. Forty-six mixtures of oil-diesel, biodiesel-diesel, and oil-biodiesel-diesel were analyzed by 1H NMR and such data were employed to design four predictive models. Thirty-six mixtures were used in the calibration set and the others in the validation. The PCR and PLS models were evaluated through statistical parameters.Briefly, PLS and PCR models were suitable for the prediction of biodiesel and oil concentration in mineral diesel. Specially, in higher concentration the predicted values were quite similar to the real ones. This fact was evidenced by the low relative errors of high concentrated samples; this means that the prediction of low concentrated samples will probably show high deviation. Therefore, 1H NMR-PLS and 1H NMR-PCR methods are fairly useful for the quality control of biodiesel-diesel blends, particularly they are suitable for prediction of concentrations greater than 2%. 相似文献
288.
Soraya Alves de Morais Crislene Rodrigues da Silva Morais Petr?nio Filgueiras de Athayde Filho B. Freitas Lira Railda Shelsea Taveira Rocha do Nascimento 《Journal of Thermal Analysis and Calorimetry》2009,97(2):437-441
The mesoionic compounds are pentagonal heterocyclic betaines with their potential use mainly in the pharmacology field due
to the diversity of their biological activities. Their exceptional electric properties lead the compounds to be investigated
in the field such as the nonlinear optical devices. In this study, five mesoionic compounds of the 1,3-thiazole-5-thiolate
system had been synthesized from amino acids derived from glycine through 1,3-dipolar cycloaddition/cycloreversion reaction.
The compounds were characterized by the use of infrared spectrometry, thermogravimetry and differential scanning calorimetry
techniques. Thermal stability of each structure was determined and characterized by the kinetic study of the thermal decomposition
by non-isothermal thermogravimetry. The DSC curves for MI-1, MI-2, MI-3, MI-4, and MI-5 demonstrated their fusion and subsequent
decomposition with the exception of MI-3, which presented only decomposition stages. The kinetic models that better described
the thermal decomposition mechanism of the mesoionic compounds achieved by the non-isothermal methods were R1, R2 and R3 (based
on the geometric models). 相似文献
289.
Rosali Maria Ferreira da Silva Flávia Patrícia Morais de Medeiros T. G. Nascimento R. O. Macêdo P. J. R. Neto 《Journal of Thermal Analysis and Calorimetry》2009,95(3):965-968
The object of the present work is to study the thermal characteristics of indinavir sulfate and to evaluate the quality of
the raw materials. Indinavir A, B, C and reference samples were obtained from different suppliers and submitted to TG, DSC
and DSC-photovisual analyses. TG/DTG curves indicated a desolvation and dehydration processes and were confirmed by DSC. According
to the DSC curves the fusion took place at about 141–142°C for indinavir C and Reference sample B and about 146–149°C for
the others. DSC-photovisual showed insoluble raw materials for indinavir C at 160°C. Indinavir sulfate is highly hygroscopic
drug which requires attention during storage and manufacture by pharmaceutical industry. 相似文献
290.
J. Dweck L. C. Morais M. V. A. Fonseca V. Campos P. M. Büchler 《Journal of Thermal Analysis and Calorimetry》2009,95(3):985-989
Aiming the use of the sewage sludge produced in one of the largest Brazilian wastewater treatment stations as a raw material
for the ceramic industry, the sintering process of the ashes produced from its calcination was evaluated by heating microscopy
thermal analysis (HMTA). From the microprocessed images, a method was developed to obtain HMTA dimensional change curves as
a function of temperature, equivalent to those usually obtained from dilatometers or by thermomechanical analysis (TMA). The
final product after sintering at 1050°C, characterized by X-ray fluorescence spectrometry, scanning electron microscopy and
X-ray dispersive energy, indicates the presence of a vitreous phase containing phosphorus, which explains the good sintering
properties of the studied calcined sludge, as shown from its HMTA dimensional change curve. 相似文献