ISSN:0100-4042
ISSN:1678-7064 on line
Volume 38, Número 2, 2015
Artigo
161 Efeito dos tratamentos superficiais nas propriedades do
bagaço da fibra de piaçava Attalea funifera Martius
Cleidiene S. Miranda, Raigenis P. Fiuza, Ricardo F.
Carvalho e Nadia M. José
The aim of this study was to investigate the effect of surface treatment on the
properties of waste piassava fiber. Washing the fibers was shown to be the best
treatment, preserving the mechanical properties of the fibers while avoiding
environmental damage.
166 Synthesis and characterization of HDTMA-organoclays:
insights into their structural properties
Pablo M. Naranjo, José Molina, Edgardo L. Sham and
Elsa M. Farfán Torres
Schema of a tactoid (stacks of parallel clay platelets) of organoclay with a “house
of cards” organization, where the surfactant is adsorbed via cationic exchange
and Van der Waals forces. The interlayered exchanged cations and the counter
ions are dispersed in the supernatant solution.
172 Flavonoides de Piper glandulosissimum Yuncker (Piperaceae)
Fabiano P. Santos, Harley da S. Alves, Edeltrudes de O.
Lima e Mª Célia de O. Chaves
This article reports the structural identification of six flavonoids and two
derivatives isolated from Piper glandulosissimum, a shrub native to Northern
Brazil. The antimicrobial activity of one flavanone was also determined.
178 Monitoramento de resíduos de agrotóxicos da classe dos
organofosforados por CG-DFC em amostras de leite fluído
e em pó
Lucia H. P. Bastos, Adherlene V. Gouvêa, Nina D. Ortiz,
Mª Helena W. M. Cardoso, Silvana do C. Jacob e Armi W.
da Nóbrega
The QuEChERS method and GC-FPD were used to evaluate the presence of OPS
pesticide residues in liquid UHT and powdered milk. Twenty five percent of the
samples were contaminated, indicating the need to improve quality control of
this product.
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185 Caracterização e atividade catalítica de K2CO3/Al2O3 na
transesterificação do óleo de girassol com aquecimento
convencional e micro-ondas
Paola E. Gama, Elizabeth R. Lachter, Rosane A. S. San
Gil, Aline V. Coelho, Isadora A. Sidi, Rodrigo L. Poubel,
Arnaldo da C. Faro Jr. e Andrea L. F. de Souza
Aluminas impregnated with potassium carbonate were active for biodiesel
production from sunflower seed oil, with high conversions by both conventional
heating and microwave irradiation.
191 Acidity of modified mordenites synthesized from rice husk
silica and catalytic transformation of methylbutynol
Sittichai Kulawong, Sanchai Prayoonpokarach, Frank
Roessner and Jatuporn Wittayakun
Zeolite mordenite in sodium form (NaMOR) was synthesized using rice husk silica;
modified with acid (A), base (B) and acid-base (AB); and acidity compared by
NH3-TPD, 27Al NMR and catalytic transformation of methylbutynol.
196 Síntese e caracterização de compósitos orgânico-inorgânicos
macroporosos para o sensoriamento de H2O2
Juliana L. Santos, Vinicius R. Gonçales, Elaine P. Cintra
e Susana I. C. de Torresi
Macroporous mediators can improve the performance of electrochemical sensors.
However, in order to take full advantage of all porous structure, kinetics of the
monitored reaction and hydrophobicity of the mediator are key points to be
analyzed.
202 Preparação e caracterização de membranas de celulose
regenerada a partir da celulose extraída de resíduos agroindustriais para aplicação em processos de separação
Edmar E. de Souza, Rayane da S. Vale, Júlia G. Vieira,
Sabrina D. Ribeiro, Guimes Rodrigues Filho, Fabiana A.
Marques, Rosana Mª N. de Assunção, Carla da S. Meireles
e Hernane da S. Barud
The membranes produced from agroindustrial residues presented lower levels
of Cu (II) ions compared with previous studies. The membranes exhibited no
cytotoxic behavior and had good transport properties.
Vol. 38, No. 2
209 Determinação de Cd e Pb em amostras de goma xantana por
GF AAS
Alexander O. de Souza, Camila C. Pereira, Bruna M. Jado,
Eliézer Q. Oreste, Mariana A. Vieira, Anderson S. Ribeiro,
Claire T. Vendruscolo e Adriane M. Nunes
This paper presents a simple, safe and inexpensive method for determination of
Cd and Pb in xanthan gum samples by GF AAS.
214 Extração de poli(3-hidroxibutirato), produzido por Cupriavidus necator, com carbonato de propileno
Luci K. M. Quines, Jaciane L. Ienczak, Mélodi Schmidt,
Kellen Zanfonato, Maria I. Rodrigues, Willibaldo Schmidell
e Gláucia M. F. Aragão
Process of extracting poly(3-hydroxybutyrate) (P(3HB)), biopolymer stored as an
intracellular energy and reserve source, from biomass of Cupriavidus necator
DSM 545 treated by temperature increase, with propylene carbonate, a low
toxicity solvent.
221 Influência do conteúdo de xilanas na branqueabilidade, propriedades higroscópicas, fisico-mecânicas e óptica de polpas
branqueadas de eucalipto
Valéria J. Gomes, Dalton Longue Jr, Jorge L. Colodette,
Robisnéa A. Ribeiro e Heder Braun
The influence of xylan content of bleached pulp on Klemm capillarity is very high
for pulps refined to a high level (P&W pulp). For tissue pulp, xylan content does
not have a strong influence on this property nor on the P&W cited earlier, even
though the values appear to be high.
227 Investigação da supressão de fluorescência de soro albumina
bovina e humana por complexo de rutênio
Mariete B. Moreira, Douglas S. Franciscato, Kalil C. F.
Toledo, João R. B. de Souza, Helena S. Nakatani e Vagner
R. de Souza
Ruthenium complex quenched bovine and human serum albumin fluorescence. The
binding sites for ruthenium complex were estimated in serum albumin. Dynamic
and static quenching for serum albumin – ruthenium complex was discussed.
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233 Método alternativo para a síntese e mecanismo de 2-(1,3-ditiano-2-ilideno)-acetonitrila
Marcelle S. Ferreira e José D. Figueroa-Villar
Simple and effective method for two-step synthesis of 2-(1,3-dithian-2-ylidene)acetonitrile (75% overall yield) and molecular modeling calculation of the
mechanism by B3LYP and the 6-311++G(2df,2p) basis set.
237 Salacia crassifolia (Celastraceae): chemical constituents and
antimicrobial activity
Vanessa G. Rodrigues, Lucienir P. Duarte, Roqueline R.
Silva, Grácia D. F. Silva, Maria O. Mercadante-Simões,
Jacqueline A. Takahashi, Bibiane L. G. Matildes, Thaisa
H. S. Fonseca, Maria A. Gomes and Sidney A. Vieira Filho
Ten pentacyclic triterpenes and a further four compounds were isolated from
leaves of Salacia crassifolia. Their structures were established through IR, 1H and
13
C NMR spectroscopic data. Some of the crude extracts and triterpenes presented
in vitro antimicrobial property.
Revisão
243 Distribuição, atividade biológica, síntese e métodos de purificação de podofilotoxina e seus derivados
Héctor H. S. Medrado, Jorge M. David, Juceni P. David e
Hugo N. Brandão
Podophyllotoxin is a precursor of three semi-synthetic commercial anticancer
agents. Today, efforts are being invested to obtain new sources of this compound.
Several processes have been developed for its synthesis, extraction, and
purification.
259 Degradação microbiológica e enzimática de polímeros: uma
revisão
Carolina Z. Costa, Marcos de C. C. de Albuquerque, Mª
Cristina Brum e Aline M. de Castro
Biotechnological (enzymatic and/or microbial) degradation of polymers for the
recovery of monomers and oligomers is promising and environmentally-friendly
technology.
Vol. 38, No. 2
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Nota Técnica
268 Monitoring of organophosphorous pesticide resdues in samples of banana, papaya, and bell pepper
Mariana F. Lemos, Mayara F. Lemos, Henrique P. Pacheco
and Rodrigo Scherer
The objective of this paper was to monitor organophosphorus residues in samples
of banana, papaya, and bell pepper from ten different markets in Vitória and Vila
Velha cities (Espírito Santo, Brazil) during a three-month period.
274 Novo sorvente de hidrofobicidade reduzida para extração em
fase sólida: preparação e caracterização
Augusto S. Novais, Jarbas F. Ribeiro Filho, Eduardo M. F.
Amaral e Anizio M. Faria
A new sorbent for solid phase extraction based on a polysiloxane with octadecyl/
hexadecyl interspersed with methyl groups immobilized on silica surface presented
lower retention for hydrophobic molecules but similar selectivity to conventional
C18 materials.
280 Kit colorimétrico para detecção de metanol em etanol combustível para o monitoramento da qualidade de combustíveis
Guilherme B. C. Martins, Mateus A. Montenegro e Paulo
A. Z. Suarez
Detection of methanol contamination in ethanol-based fuels by simple colorimetric
qualitative or semi qualitative analysis adapted for ease of use in the field.
Educação
285 Enzymatic resolution of antidepressant drug precursors in
an undergraduate laboratory
Luís M. R. Solano and Nuno M. T. Lourenço
This paper describes a multi-step chemo-enzymatic synthesis of antidepressant
drug precursors.
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288 Estrategia de doble ciclo de supervisión clínica para la mejora
de la calidad docente en la universidad. Punto de vista del
profesorado novel
Diego Airado Rodríguez y María D. Víctor Ortega
A strategy based on a double clinical supervision cycle has been implemented
to enhance the quality of university teaching. Planning, action, analysis and
reflection stages are well delimited.
293 Corrosão do aço-carbono: uma abordagem do cotidiano no
ensino de química
Marcos V. F. Silva, Marinalda C. Pereira, Eduardo N.
Codaro e Heloisa A. Acciari
The visual colorimetric technique can be used to determine soluble product
concentration during corrosion reactions.