Autores: informamos que, a partir do próximo fascículo (39/9), a revista Química Nova adotará a licença CC-BY. Mais informações a respeito dessa licença podem ser obtidas aqui.
The Board of Directors of the Sociedade Brasileira de Química-SBQ (publisher of the Química Nova-QN) decided that QN will adopt the full open access format in which authors are required to cover part of the publication costs for their articles. See more...
Juliana L. SantosI; Vinicius R. GonçalesII,#; Elaine P. CintraI; Susana I. Córdoba de TorresiII,*
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.
Cleidiene S. MirandaI; Raigenis P. FiuzaII; Ricardo F. CarvalhoIII; Nadia M. JoséI,*
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.
Pablo M. NaranjoI,*; José MolinaII; Edgardo Ling Sham I,III; Elsa M. Farfán TorresI,II
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.
Fabiano Pereira SantosI; Harley da Silva AlvesII,*; Edeltrudes de Oliveira LimaIII; Maria Célia de Oliveira ChavesIII
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.
Lucia Helena Pinto Bastos*; Adherlene Vieira Gouvêa; Nina Daddário Ortiz; Maria Helena Wohlers Morelli Cardoso; Silvana do Couto Jacob ; Armi Wanderley 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.
Paola E. GamaI; Elizabeth R. LachterI,*; Rosane A. S. San GilI; Aline V. CoelhoI; Isadora A. SidiI; Rodrigo L. PoubelI; Arnaldo da Costa Faro Jr.I; Andrea L. F. de SouzaII
Aluminas impregnated with potassium carbonate were active for biodiesel production from sunflower seed oil, with high conversions by both conventional heating and microwave irradiation.
Sittichai KulawongI; Sanchai PrayoonpokarachI; Frank RoessnerII; Jatuporn WittayakunI,*
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.
Edmar Eustáquio de SouzaI; Rayane da Silva ValeI; Júlia Graciele VieiraI; Sabrina Dias RibeiroI; Guimes Rodrigues FilhoI; Fabiana Aparecida MarquesII; Rosana Maria Nascimento de AssunçãoIII,*,#; Carla da Silva MeirelesIV; Hernane da Silva BarudV,VI
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.
Alexander O. de SouzaI; Camila C. PereiraI; Bruna M. JadoI; Eliézer Q. OresteI; Mariana A. VieiraI; Anderson S. RibeiroI; Claire T. VendruscoloII ; Adriane M. NunesI,*
This paper presents a simple, safe and inexpensive method for determination of Cd and Pb in xanthan gum samples by GF AAS.
Luci K. M. QuinesI; Jaciane L. IenczakII; Mélodi SchmidtI; Kellen ZanfonatoI; Maria I. RodriguesIII; Willibaldo SchmidellI; Gláucia M. F. AragãoI,*
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.
Valéria J. GomesI,*; Dalton Longue JrII; Jorge L. ColodetteII; Robisnéa A. RibeiroII; Heder BraunIII
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.
Mariete B. Moreira; Douglas S. Franciscato; Kalil C. F. Toledo; João Raul B. de Souza; Helena S. Nakatani; 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.
Marcelle S. Ferreira; 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.
Vanessa G. RodriguesI,*; Lucienir P. DuarteI; Roqueline R. SilvaII; Grácia D. F. SilvaI; Maria O. Mercadante-SimõesIII; Jacqueline A. TakahashiI; Bibiane L. G. MatildesI; Thaisa H. S. FonsecaIV; Maria A. GomesIV; Sidney A. Vieira FilhoV
Ten pentacyclic triterpenes and a further four compounds were isolated from leaves of Salacia crassifolia. Their structures were established through IR, 1H and 13C NMR spectroscopic data. Some of the crude extracts and triterpenes presented in vitro antimicrobial property.
Héctor Hugo S. MedradoI; Jorge M. DavidI,*; Juceni P. DavidII; Hugo N. BrandãoIII
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.
Carolina Zanon CostaI,II; Marcos de C. C. de AlbuquerqueI,II; Maria Cristina BrumII; Aline Machado de CastroII,*
Biotechnological (enzymatic and/or microbial) degradation of polymers for the recovery of monomers and oligomers is promising and environmentally-friendly technology.
Mariana F. Lemos; Mayara F. Lemos; Henrique P. Pacheco; 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.
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.
Guilherme B. C. Martins; Mateus A. Montenegro; 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.
Luís M. R. SolanoI; Nuno M. T. LourençoII,*
This paper describes a multi-step chemo-enzymatic synthesis of antidepressant drug precursors.
Diego Airado Rodríguez*,I; María Dolores Víctor OrtegaII
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.
Marcos V. F. Silva; Marinalda C. Pereira; Eduardo N. Codaro; Heloisa A. Acciari*
The visual colorimetric technique can be used to determine soluble product concentration during corrosion reactions.
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