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...
André Luis Dantas Ramos * , #, I; Stefania TanaseII; Gadi RothenbergII
Metal-organic frameworks are synthesized by the self-arrangement of construction blocks. Their final structure consists of metals or metal clusters, acting as nodes; they are linked together by a spacer, such as organic molecules with multiple branches, forming a three-dimensional network, which can have a very high surface area, making it possible to accommodate host molecules in its interior.
Emerson Roberto Santos*, I; Shu Hui WangI; Fabio Conte CorreiaI; Ivan Rodrigues CostaII; Victor SonnenbergII; Elvo Calixto Burini JuniorIII; Roberto Koji OnmoriIV
Organic light-emitting diode (OLED) device architecture is explored in this study.
Aline Colvara de Almeida Pinheiro; Meibel Teixeira Lisboa; Anderson Schwingel Ribeiro; Adriane Medeiros Nunes*; Alzira Yamasaki
A reflux system, which allows continuous circulation of water, is used for rice sample preparation, and is followed by the determination of Cu, Fe, Mn, and Zn by flame atomic absorption spectrometry.
André F. ConstantinoI; Valdemar Lacerda Jr.*, I; Reginaldo B. dos SantosI; Sandro J. GrecoI; Renzo C. SilvaI; Álvaro C. NetoI; Lúcio L. BarbosaI; Eustáquio V. R. de CastroI; Jair C. C. FreitasII
Factors such as the content and quality of lipids present in oil matrices, evaluated using the low-field NMR technique coupled to chemometric methods, can collaborate in choosing the best source for biodiesel production in a given region
Samara Boaventura de Moraes; Rodrigo Botan; Liliane Maria Ferrareso Lona*
A layered hydroxide salt is modified using an organic molecule; ion exchange occurs between the anions of the layered hydroxide salt and those of the organic molecule. Subsequently, it is added to the monomer, thereby forming the nanocomposite.
Vinicius Emmanuel de Oliveira dos Santos*, I; Vinicius Guilherme CelanteII; Maria de Fátima Fontes LelisI; Marcos Benedito José Geraldo de FreitasI
Hydrometallurgical process with the characterization of both the precursor material (anode) and the recovered materials (lanthanides).
Silvio Manea*; Gabriela Knippelberg B. Manea; Koshun Iha; José A. F. F. Rocco
The figure represents the electrical charging of the composite solid propellant, it may generate an internal electrostatic discharge in the solid propellant when it reaches its electric potential breakdown.
Fábio Israel M. Carvalho*; Heronides A. Dantas Filho
The principal component analysis(PCA) was applied to discriminate the samples studied, which revealed the separation of four groups according to their chemical composition determined in samples collected from the eight fuel distributors in the State of Pará.
Ivanira Moreira; Guilherme Luiz Scheel; Pedro Henrique Hatumura; Ieda Spacino Scarminio*
Statistical schedules of mixtures associated with HPLC-UV-DAD spectra were used to evaluate the effect of solvents on the extraction of chlorogenic acids, caffeine, and trigonelline in four coffee varieties: Bourbon, IAPAR59, IPR101, and IPR108.
Luiz Rodrigo Ito Morioka; Ângelo Paggi Matos*; Gisele Olivo; Ernani Sebastião Sant'Anna
Details of C. vulgaris growth on concentrated desalination and Bold Basal Medium (BBM): A - Growth curves; B - Optimization of flocculation by response surface methodology; C - Cultivation of C. vulgaris and flocculated biomass; D - Dried biomass of C. vulgaris.
Ulisses N. AguiarI; Sidney G. de LimaI, II, *; Márcio S. RochaI; Rivelilson Mendes de FreitasI; Talita M. OliveiraI; Raiane M. SilvaII; Lara C. B. MouraII; Lorena T. G. de AlmeidaII
Essential oil of Croton zehntneri (a plant native of northeastern Brazil), whose main component is estragole, was complexed with β-cyclodextrin and characterized by Vibrational Spectroscopy and Differential Scanning Calorimetry.
Fernando A. Santos*; José H. de Queiroz; Jorge L. Colodette; Mauro Manfredi; Maria Eliana L. R. Queiroz; Celso S. Caldas; Filippe E. F. Soares
The cellulosic ethanol production process involves three steps: (i) pre-treatment to disrupt the crystalline structure of cellulose; (ii) enzymatic hydrolysis to hydrolyze polysaccharides into fermentable sugars; and (iii) fermentation process to convert sugars into ethanol.
Queila O. dos SantosI; Marcos A. BezerraI; Giovana de Fátima LimaII; Kristiany M. DinizIII; Mariana G. SegatelliIII; Talitha O. GerminianoIII; Vivian da Silva SantosIV; César R. T. Tarley*, III, V
A mini-column containing the polymer impregnated with zinc, the scanning electron microscopy of the material, and the schematic of the interaction of zinc ions in the selective cavity of the material.
Ramon G. de OliveiraI; Edilson B. Alencar-FilhoII; Mário L. A. A. VasconcellosI, *
We present here a theoretical study by molecular docking which demonstrate the selective interaction between Piperine with CYP3A4.
Xinghui Jin; Bingcheng Hu*; Huanqing Jia; Zuliang Liu; Chunxu Lu
Detonation properties of the guanidine-fused bicyclic skeleton derivatives C4N6H8-n(NO2)n (n=1-6) were calculated using density functional theory.
Shweta ParohaI; Ravindra Dhar DubeyII; Subrata MallickI, *
Interaction of naproxen with calcium carbonate after freeze-drying the wet-state equilibrated mixture has been investigated.Study revealed the acid-base reaction,and drug release increased with the increase of calcium carbonate in the formulations.
Juan Alberto Moo-PucI; Zhelmy Martín-QuintalI; Gumersindo Mirón-LópezI; Rosa Esther Moo-PucII; Leovigildo QuijanoIII; Gonzalo J. Mena-RejónI, *
From Maytenusphyllanthoidesleaves, cyclolignan(+)-lyoniresinol was isolated and tested against Trichomonas vaginalis, showing activity at IC50 17.57 µM.This is the first report on the occurrence of lyoniresinol in Maytenus genus, and on itsanti-trichomonal activity.
Priscila Moraes dos SantosI; Patrícia Danielle Oliveira de AlmeidaII; Emerson Silva LimaII; Manoel Odorico de MoraesIII; Patrícia Marçal da CostaIII; Assuero Silva MeiraIII; Cláudia do Ó PessoaIII; Ligia Maria Marino ValenteIV; Valdir Florêncio da Veiga JuniorI, *
Extracts of leaves and twigs of Fabaceae Bauhinia purpurea were collected from central and northern Amazonia and partitioned, and the flavonoid fractions were analyzed by HPLC-DAD and MS; distinct chromatographic profiles were observed, especially those indicating the presence of rutin and isoquercitrin. The extracts and flavonoid fractions exhibited excellent antioxidant activity and were comparable with that of the standard; however, they did not exhibit cytotoxicity to MDA-MB435 (lung), HCT-8 (colon), and SF-295 (glioblastoma) tumor cell lines.
Márcia N. S. de la CruzI; Helvécio M. dos Santos JúniorI; Claudia M. Rezende*, I; Ruy J. V. AlvesII; Eliana M. CancelloIII; Maurício M. da RochaIII
The front gland of Nasutitermes termite soldiers is mainly formed by mono and diterpenes with trinervitane, kempane and rippertane skeletons, only found in termites. This article reviews the scientific literature from interesting aspects of behavior and chemical composition.
Cristiano ChristofaroI, *; Mônica M. D. LeãoII
Concentrations below the detection limit (DL) are frequently observed in environmental studies. This study discusses the main methods of treating censored data presented in specialist literature, comparing their limitations and advantages.
Érica Pacheco-SilvaI; Jurandir Rodrigues de SouzaI; Eloisa Dutra Caldas*, II
The use of veterinary drugs in food-producing animals can leave residues in food. Human exposure to these residues through consumption of animal products can pose a health risk.
Iraci da Anunciação Pereira; Viviane Carvalho Nogueira; Michele Odnicki da Silva; Marcos Henrique Mamoru Otsuka Hamanaka; Valdirene Sullas Teixeira Peressinotto; Elaine Fernanda Zen Ávila Von Zuben; Thebano Emílio de Almeida Santos*
Illustration of cathode evaporation using a shadow mask for patterning OLED devices:A) Stainless steel shadow mask, B) 4 OLED devices with 9mm2 active area: glass-ITO/PEDOT/PFO/Al, C) picture of OLED devices and D) picture of an OLED device emitting light.
Vanessa de Jesus GaffneyI; Vitor Vale Cardoso*, II; Alexandre RodriguesII; Elisabete FerreiraII; Maria João BenolielII; Cristina M. M. AlmeidaI
A method was developed for the analysis of 31 pharmaceuticals in water by SPE-UPLC-MS/MS. Instrumental conditions were optimized to allow the quantification of trace levels of the analytes. The method was validated through the estimation of the linearity range, method detection and quantification limits, matrix effects, recovery studies, precision and accuracy.
Ananda L. Sanson*; Bruno E. L. Baeta; Keila L. T. Rodrigues; Robson J. C. F. Afonso
A low cost apparatus for SPE was developed that uses nitrogen under positive pressure, ensures the maintenance of the sample flow, allows simultaneous extraction of different samples without cross-contamination and sample contact with plastic materials.
Fernanda Fernandes Heleno; Maria Eliana Lopes Ribeiro de Queiroz*; Antônio Augusto Neves; André Fernando de Oliveira
The SLE/LTP-GC/ECD method was optimized, validated and applied in monitoring of the dissipation/persistence of difenoconazole residues in strawberries that received multiple applications of a commercial product containing this active ingredient.
Maria Cristina DiCiaulaI; Gisely C. LopesI; Ieda S. ScarminioII; João Carlos P. de MelloI, *
A statistical mixture-design technique was used to study the effects of different solvents and their mixtures on the yield, total polyphenol content, and antioxidant capacity of the crude extracts from the bark of Schinus terebinthifolius.
Ramon Kenned Sousa AlmeidaI; Cláudia MartelliI; Gilson Herbert Magalhães DiasI; Julio Cesar Araujo da SilvaII, *
An efficient and inexpensive device for undergraduate chemistry classes aiming teaching the photolytic synthesis concepts. This device presents simplicity, low costs, class-compatible reaction times and good yields.
Pillared clays and regular mesoporous silicas are examples of nanoporous materials whose porosity can be quantified by X-ray diffraction
Mário L. A. A. Vasconcellos*
We present here our didactic experience on teaching Pearson theory (HSAB) for graduated students in organic chemistry.
Célia Ferreira Frias; Sílvia Alexandre Gramacho; Marta Pineiro*
A case study for the application of assisted derivatization by microwave and gas chromatography-mass spectrometry for the identification of glucose isomers.
Rodrigo Cristiano*; Marília Gabriela B. Cabral; Rafael B. de Aquino; Cláudia M. Z. Cristiano
This article describes a multi-step synthesis for acquiring liquid crystals derived from nitroazobenzene, which is used in the Experimental Organic Chemistry II classes.
Lediany Forostecki; Ourides Santin Filho*
At the end of the 19th century, a group named Occult Chemists suggested that they could "see" atoms by clairvoyance. They devised the structure of an "ultimate physical atom" (the anu), that enters in the composition of all substances and predicted the existence of isotopes.
Hugo Orofino; Sergio P. Machado; Roberto B. Faria*
On-line version ISSN 1678-7064 Printed version ISSN 0100-4042
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