Chemistry
Mostrando 49-60 de 2733 artigos, teses e dissertações.
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49. A IMPORTÂNCIA DAS CUMARINAS PARA A QUÍMICA MEDICINAL E O DESENVOLVIMENTO DE COMPOSTOS BIOATIVOS NOS ÚLTIMOS ANOS
Coumarins are natural products characterized as 2H-chromen-2-one, according to IUPAC nomenclature, largely distributed in plants, as well as, in species of fungi and bacteria. Nowadays, many synthetic procedures allow the discovery of coumarins with expanded chemical space. The ability to exert non-covalent interactions with many enzymes and receptors in liv
Quím. Nova. Publicado em: 2021-02
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50. CHLORDECONE ADSORPTION ON FUNCTIONALIZED ACTIVATED CARBONS: COMPUTATIONAL CHEMISTRY AS A TOOL FOR UNDERSTANDING THE ADSORPTION PROCESS
Chlordecone (CLD) has been used as a pesticide for a long time to control the proliferation of various insects in tropical countries like the French West Indies. CLD was included in 2009 in the list of persistent organic pollutants (POPs) by the Stockholm Convention, prohibiting its production and use worldwide. Thus, its removal from water and soils is a sa
Quím. Nova. Publicado em: 2021-02
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51. GALILEO’S PENDULUM AS A MAGNETIC BALANCE FOR STUDYING CHEMICAL MAGNETISM AT HOME
A very simple, but rich experiment, encompassing a classical Galileo’s pendulum, has been devised to be performed at home, especially during the Covid-19 pandemics. The experiment uses a miniature supermagnet rod as the pendulum oscillating element suspended from a fixed sewing thread. Its physics can be fully investigated, allowing to study the oscillatio
Quím. Nova. Publicado em: 2021-01
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52. GREEN CHEMISTRY TEACHING FOR SUSTAINABILITY IN PAPERS PUBLISHED BY THE JOURNAL OF CHEMICAL EDUCATION
This paper discusses 286 proposals and reports of Green Chemistry (GC) teaching experiences, in papers of the Journal of Chemical Education (JCEd) until 2019. The analysis was based on previous categories: source-problem, paper focus, subjects/area of knowledge, target groups, GC contents, type of approach and purpose(s) of the proposal. A list of possible c
Quím. Nova. Publicado em: 2020-12
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53. NANOMATERIAIS PLASMÔNICOS: PARTE II. QUÍMICA DE COORDENAÇÃO DE SUPERFÍCIE E SUA APLICAÇÃO EM SENSORES E CATALISADORES
In this second part we will discuss how surface chemistry properties of plasmonic nanomaterials can be tailored by applying coordination chemistry, supramolecular and materials chemistry approaches, in which nanoparticles with well-controlled features conjugated with properly chosen molecules are the basis of functional organized structures that can be appli
Quím. Nova. Publicado em: 2020-12
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54. A PROBLEMATIZAÇÃO DA ABORDAGEM TEMÁTICA NA FORMAÇÃO INICIAL DE PROFESSORES DE QUÍMICA
The thematic approach supported by Paulo Freire’s reference has been the object of study in the Teaching of Nature Sciences. In this work we analyzed which knowledge is explained by two undergraduate students about limits and potentialities related to the planning and development of a thematic approach promoted in the context of a supervised curricular int
Quím. Nova. Publicado em: 2020-12
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55. NANOMATERIAIS PLASMÔNICOS: PARTE I. FUNDAMENTOS DA ESPECTROSCOPIA DE NANOPARTÍCULAS E SUA RELAÇÃO COM O EFEITO SERS
We perform an analysis of plasmonic nanomaterials in a two part review, the first of which constitutes the present work. Here, attention is given to the fundamentals of metal nanoparticle optical properties. It is discussed the principles regarding the excitation of localized surface plasmon modes in nanostructures of different sizes, shapes and surrounding
Quím. Nova. Publicado em: 2020-12
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56. 2021. Un año de incertidumbres para la Educación Matemática
This work describes a methodology to carry out the analysis of technological sectors, using information contained in patent documents. The use of this information by professors and students of chemistry courses and related areas is still little used. The consequence of this is the repetition of efforts to obtain some results of research and development. The
Bolema. Publicado em: 2020-12
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57. EXTRACTION AND IDENTIFICATION OF FORMULATIONS OF ANABOLIC ANDROGENIC STEROIDS: A FORENSIC EDUCATIONAL APPROACH
The use of anabolic androgenic steroids is largely restricted worldwide since they are associated with innumerous side effects and health damage. However, apprehensions of formulations of anabolic agents have been extensively increasing throughout the world, making their analysis a common task in the forensic field. In this sense, a set of three experiments
Quím. Nova. Publicado em: 2020-12
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58. AUTENTICAÇÃO DE ORÉGANO (Origanum vulgare L.) ORGÂNICO UTILIZANDO ESPECTROSCOPIA NIR E QUIMIOMETRIA
In recent years, the consumption of organic foods has considerably increased. The basic difference between organic and non-organic food products is the way in which they are produced and processed, and the authenticity of these products is a current trend in food science and analytical chemistry. In this sense, the objective of this work was to propose an an
Quím. Nova. Publicado em: 2020-12
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59. PATENTOMETRIA: UMA FERRAMENTA INDISPENSÁVEL NO ESTUDO DE DESENVOLVIMENTO DE TECNOLOGIAS PARA A INDÚSTRIA QUÍMICA
This work describes a methodology to carry out the analysis of technological sectors, using information contained in patent documents. The use of this information by professors and students of chemistry courses and related areas is still little used. The consequence of this is the repetition of efforts to obtain some results of research and development. The
Quím. Nova. Publicado em: 2020-12
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60. Synthesis and Antioxidant and Antimicrobial Properties of β-Hydroxy Sulfides, Sulfoxides, and Sulfones Derived from Cardanol and Glycerol Derivatives
Natural and synthetic sulfur-bearing organic compounds have many applications in medicinal chemistry. This article reports the preparation of amphiphilic β-hydroxy sulfides, sulfoxides, and sulfones derived from cardanol and glycerol. Thiolysis of cardanol epoxide 3 with various thiols (4a-4j) in ethanol or water yielded the corresponding β-hydroxy sulfide
J. Braz. Chem. Soc.. Publicado em: 2020-12