Chemistry Laboratories
Mostrando 1-12 de 48 artigos, teses e dissertações.
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1. EL DOPAJE DEPORTIVO COMO CUESTIÓN SOCIALMENTE VIVA: UNA REVISIÓN BIBLIOGRÁFICA
This paper aims to present a review of the concept doping in scientific journals published in the period 2008 to 2018. The diversity of approaches that position doping as a socially acute question (SAQ) allow us to recognize the implications of this concept in educational contexts. The state of the art methodology seeks to reflexively recover production on t
Quím. Nova. Publicado em: 21/10/2019
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2. MEASURING THE CONDUCTIVITY OF VERY DILUTE ELECTROLYTE SOLUTIONS, DROP BY DROP
Undergraduate experiments on ionic conductivity are common practice in general chemistry and advanced physical chemistry laboratories. Often, the conductivities are measured for solutions prepared for various salts, in a range of concentrations, and the relationship between solution conductivity and concentration is interpreted in terms of the Kohlrausch law
Quím. Nova. Publicado em: 2018-07
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3. Organic Synthesis: New Vistas in the Brazilian Landscape
ABSTRACT In this overview, we present our analysis of the future of organic synthesis in Brazil, a highly innovative and strategic area of research which underpins our social and economical progress. Several different topics (automation, catalysis, green chemistry, scalability, methodological studies and total syntheses) were considered to hold promise for t
An. Acad. Bras. Ciênc.. Publicado em: 2018
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4. Analysis of Blotter Papers Employed in the Commercialization of New Hallucinogenic Substances of the 2,5-Dimethoxy- N-(2-methoxybenzyl) Phenethylamine Series Seized in the City of Bogotá by Applying Gas Chromatography Coupled to a Selective Mass Ion Trap Detector
In recent years, the production, distribution and consumption of so-called new psychoactive substances, such as synthetic cannabinoids, synthetic cathinones, and phenethylamines, have increased worldwide. The present work reports the identification of such substances found in samples of blotter papers that were seized in the city of Bogotá in accordance wit
J. Braz. Chem. Soc.. Publicado em: 2016-06
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5. "Photo" Chemistry Without Light?
In the early seventies, Giuseppe Cilento (São Paulo University), Emil White (Johns Hopkins University) and Angelo Lamola (AT&T Bell Laboratories) postulated that typical photochemical reactions could occur in dark parts of living organisms if coupled to enzymatic sources of electronically excited products. Their paradoxical hypothesis of "photochemistry wit
J. Braz. Chem. Soc.. Publicado em: 2015-12
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6. TREATMENT OF WASTE FROM ATOMIC EMISSION SPECTROMETRIC TECHNIQUES AND REUSE IN UNDERGRADUATE LAB CLASSES FOR QUALITATIVE ANALYSIS
Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma optical emission spectrometry (ICP OES) are widely used in academic institutions and laboratories for quality control to analyze inorganic elements in samples. However, these techniques have been observed to underperform in sample nebulization processes. Most of the samples processed
Quím. Nova. Publicado em: 2015-11
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7. ENZYMATIC RESOLUTION OF ANTIDEPRESSANT DRUG PRECURSORS IN AN UNDERGRADUATE LABORATORY
The use of biocatalysts in synthetic chemistry is a conventional methodology for preparing enantiomerically enriched compounds. Despite this fact, the number of experiments in chemical teaching laboratories that demonstrate the potential of enzymes in synthetic organic chemistry is limited. We describe a laboratory experiment in which students synthesized a
Quím. Nova. Publicado em: 2015-02
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8. Explorando produtos naturais microbianos nas fronteiras da Química e da Biologia
The chemistry of natural products has been remarkably growing in the past few decades in Brazil. Aspects related to the isolation and identification of new natural products, as well as their biological activities, have been achieved in different laboratories working on this subject in the country. More recently, the introduction of new molecular biology tool
Quím. Nova. Publicado em: 2013
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9. Adição de anilinas à naftoquinona em água e em fase sólida
Considering all the aspects of the principles of green chemistry, we present herein the addition reactions of amines to 1,4-naphthoquinone in water as solvent and also in solid phase. These reactions resulted in very colorful products that were easily monitored by thin layer chromatography and consequently easy to separate. Therefore, they are interesting ex
Química Nova. Publicado em: 2012
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10. Reações multicomponentes de Biginelli e de Mannich nas aulas de química orgânica experimental: uma abordagem didática de conceitos da química verde
The introduction of Mannich and Biginelli multicomponent reactions in a practical Organic Chemistry course is presented in this article. Procedures described in the literature were adapted for use under the simple conditions available in undergraduate laboratories and were selected on the basis of Green Chemistry principles and practicality of synthesis. The
Quím. Nova. Publicado em: 2012
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11. Novas métricas holísticas para avaliação da verdura de reações de síntese em laboratório
New semi-quantitative metrics for simple evaluation of global greenness of chemical reactions used in teaching laboratories, namely, the Green Circle (GC) and Green Matrix (GM), were developed. These metrics globally consider all Twelve Principles of Green Chemistry. To illustrate their construction, the greenness of several syntheses performed in the labora
Quím. Nova. Publicado em: 2012
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12. Análise forense: pesquisa de drogas vegetais interferentes de testes colorimétricos para identificação dos canabinoides da maconha (Cannabis Sativa L.)
Marijuana (Cannabis sativa L.) is the most cultivated, trafficked and consumed illicit drug worldwide. Estimates indicate 10% of individuals experiencing marijuana become daily users, and 20-30% use it weekly. Around 489 natural compounds have been identified in this plant, of which 70 are cannabinoids, responsible for psychic effects. The most relevant cann
Quím. Nova. Publicado em: 2012