Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170947
Jinfeng Zhou, Chun-Yao Chu
In this work, a recyclable and sensitive fluorescent nanoprobe, RhoB@ZIF-8 composite, has been designed and successfully synthesized by encapsulating rhodamine B (abbreviated as RhoB) into the cavities of zeolitic imidazolate framework-8 (ZIF-8) metal-organic frameworks (MOFs) through a facile one-pot method under mild conditions. The RhoB@ZIF-8 composite exhibited an emission band at 589 nm with fluorescent quantum yield of 19.8%. Since there was an efficient overlap between the absorption of malachite green (MG) and the fluorescence spectra (excitation and emission bands) of RhoB@ZIF-8 composite, the fluorescence intensity decreased sharply after MG was added. The fluorescence quenching was linear with the concentration of MG in the range of 0 to 13.0 μM with a low limit of detection (LOD) of 0.089 μM. Remarkably, this proposed sensing system has good performances including high specificity, good stability and recyclability. Finally, this fluorescent probe was successfully applied to the detection of MG in aquaculture water and fish tissue samples, revealing its potential practicability. This work will provide us a new research platform for MG sensing.
{"title":"ONE-POT SYNTHESIS OF A REVERSIBLE AND SENSITIVE FLUORESCENT PROBE FOR THE DETECTION OF MALACHITE GREEN","authors":"Jinfeng Zhou, Chun-Yao Chu","doi":"10.21577/0100-4042.20170947","DOIUrl":"https://doi.org/10.21577/0100-4042.20170947","url":null,"abstract":"In this work, a recyclable and sensitive fluorescent nanoprobe, RhoB@ZIF-8 composite, has been designed and successfully synthesized by encapsulating rhodamine B (abbreviated as RhoB) into the cavities of zeolitic imidazolate framework-8 (ZIF-8) metal-organic frameworks (MOFs) through a facile one-pot method under mild conditions. The RhoB@ZIF-8 composite exhibited an emission band at 589 nm with fluorescent quantum yield of 19.8%. Since there was an efficient overlap between the absorption of malachite green (MG) and the fluorescence spectra (excitation and emission bands) of RhoB@ZIF-8 composite, the fluorescence intensity decreased sharply after MG was added. The fluorescence quenching was linear with the concentration of MG in the range of 0 to 13.0 μM with a low limit of detection (LOD) of 0.089 μM. Remarkably, this proposed sensing system has good performances including high specificity, good stability and recyclability. Finally, this fluorescent probe was successfully applied to the detection of MG in aquaculture water and fish tissue samples, revealing its potential practicability. This work will provide us a new research platform for MG sensing.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170953
M. Silva, Leila Gimenes, Paulete Romoff, Marisi Soares, Fernanda Camilo, Erica Levatti, A. Tempone, J. H. Lago
ANTI-Trypanosoma cruzi PHENYLPROPANOIDS ISOLATED FROM Baccharis ligustrina C. DC. (ASTERACEAE). In the present work, dried aerial parts of Baccharis ligustrina (Asteraceae) were subjected to microwave assisted extraction (MAE) using aqueous solution of 1-butyl-3-methylimidazolium bromide (BMImBr) and the obtained extract was successively partitioned using hexane and EtOAc. Using reduced amounts of extracts and efficient chromatographic steps, four acyl C6C3 derivatives (n-hexacosyl ferulate, n-hexacosyl, n-octacosyl, and n-triacontyl p-coumarates) were obtained from hexane phase whereas two C6C3 acids (ferulic and p-coumaric) were obtained from EtOAc phase. Isolated phenylpropanoids were evaluated against amastigote forms of parasite Trypanosoma cruzi. As result, it was observed that p-coumaric and ferulic acids were inactives whereas alkyl derivatives displayed EC50 values of 6.5 µmol L-1 (n-octacosyl p-coumarate), 9.3 µmol L-1 (n-triacontyl p-coumarate), 15.7 µmol L-1 (n-hexacosyl p-coumarate), and 32.2 µmol L-1 (n-hexacosyl ferulate). All tested compounds displayed reduced toxicity against NCTC cells (CC50 > 200 mmol L-1).
{"title":"FENILPROPANOIDES COM AÇÃO ANTI-Trypanosoma cruzi ISOLADOS DE Baccharis ligustrina C. DC. (ASTERACEAE)","authors":"M. Silva, Leila Gimenes, Paulete Romoff, Marisi Soares, Fernanda Camilo, Erica Levatti, A. Tempone, J. H. Lago","doi":"10.21577/0100-4042.20170953","DOIUrl":"https://doi.org/10.21577/0100-4042.20170953","url":null,"abstract":"ANTI-Trypanosoma cruzi PHENYLPROPANOIDS ISOLATED FROM Baccharis ligustrina C. DC. (ASTERACEAE). In the present work, dried aerial parts of Baccharis ligustrina (Asteraceae) were subjected to microwave assisted extraction (MAE) using aqueous solution of 1-butyl-3-methylimidazolium bromide (BMImBr) and the obtained extract was successively partitioned using hexane and EtOAc. Using reduced amounts of extracts and efficient chromatographic steps, four acyl C6C3 derivatives (n-hexacosyl ferulate, n-hexacosyl, n-octacosyl, and n-triacontyl p-coumarates) were obtained from hexane phase whereas two C6C3 acids (ferulic and p-coumaric) were obtained from EtOAc phase. Isolated phenylpropanoids were evaluated against amastigote forms of parasite Trypanosoma cruzi. As result, it was observed that p-coumaric and ferulic acids were inactives whereas alkyl derivatives displayed EC50 values of 6.5 µmol L-1 (n-octacosyl p-coumarate), 9.3 µmol L-1 (n-triacontyl p-coumarate), 15.7 µmol L-1 (n-hexacosyl p-coumarate), and 32.2 µmol L-1 (n-hexacosyl ferulate). All tested compounds displayed reduced toxicity against NCTC cells (CC50 > 200 mmol L-1).","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170949
E. Rocha, Yasmin Salmazo, Marcio Hayashi, César Zaragoza, Emilio Lucca
LATE-STAGE FUNCTIONALIZATION OF C—H BONDS IN ORGANIC SYNTHESIS. The development of new strategies for the functionalization of the historically inert C—H bond arises as an excellent way to create new carbon—carbon and carbon— heteroatom bonds. With increasingly chemo- and site-selective methods that enables the late-stage functionalization of C—H bonds, the modification of specific sites in natural products and pharmaceuticals without altering their scaffold emerges as a powerful means for the diversification of complex molecules. In this review, we will introduce concepts of late-stage modifications, the use of C—H bond functionalization to forge new carbon—carbon and carbon—heteroatom bonds using metal catalysis and photochemistry in simple examples and their applications in natural products and pharmaceuticals. The aim of the review is to update and display to the reader the contributions and implications of this methodology to organic synthesis.
{"title":"FUNCIONALIZAÇÃO DE LIGAÇÕES C—H EM ESTÁGIO TARDIO EM SÍNTESE ORGÂNICA","authors":"E. Rocha, Yasmin Salmazo, Marcio Hayashi, César Zaragoza, Emilio Lucca","doi":"10.21577/0100-4042.20170949","DOIUrl":"https://doi.org/10.21577/0100-4042.20170949","url":null,"abstract":"LATE-STAGE FUNCTIONALIZATION OF C—H BONDS IN ORGANIC SYNTHESIS. The development of new strategies for the functionalization of the historically inert C—H bond arises as an excellent way to create new carbon—carbon and carbon— heteroatom bonds. With increasingly chemo- and site-selective methods that enables the late-stage functionalization of C—H bonds, the modification of specific sites in natural products and pharmaceuticals without altering their scaffold emerges as a powerful means for the diversification of complex molecules. In this review, we will introduce concepts of late-stage modifications, the use of C—H bond functionalization to forge new carbon—carbon and carbon—heteroatom bonds using metal catalysis and photochemistry in simple examples and their applications in natural products and pharmaceuticals. The aim of the review is to update and display to the reader the contributions and implications of this methodology to organic synthesis.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170966
Pedro Pereira, Jean de Andrade, Pedro Maia, G. Malpass
An inert atmosphere is, in some cases, important for the performing of experiments where substances are toxic and/or sensitive to oxygen. However, the high cost and accessibility of an equipment to work under these conditions, results in the fact that most laboratories do not have this kind of equipment. In this paper, we present a simple and efficient project to build a cheap glove box for processes that require an inert atmosphere. The proposed glove box is made using medium density fiberboard (MDF), an acrylic lid, hinges, air valves, PVC gloves and other materials that can be found easily in local stores or on the internet. Tests to verify the quality of the nitrogen atmosphere were performed using the lighter test and niobium pentachloride (NbCl5), which is a moisture/oxygen sensitive material. The results demonstrated that the equipment is able to maintain an inert atmosphere for several hours, does not permit lighter to function and maintains the NbCl5 stable.
{"title":"AN ACCESSIBLE GLOVE BOX PROJECT FOR PROCEDURES THAT REQUIRE INERT CONDITIONS","authors":"Pedro Pereira, Jean de Andrade, Pedro Maia, G. Malpass","doi":"10.21577/0100-4042.20170966","DOIUrl":"https://doi.org/10.21577/0100-4042.20170966","url":null,"abstract":"An inert atmosphere is, in some cases, important for the performing of experiments where substances are toxic and/or sensitive to oxygen. However, the high cost and accessibility of an equipment to work under these conditions, results in the fact that most laboratories do not have this kind of equipment. In this paper, we present a simple and efficient project to build a cheap glove box for processes that require an inert atmosphere. The proposed glove box is made using medium density fiberboard (MDF), an acrylic lid, hinges, air valves, PVC gloves and other materials that can be found easily in local stores or on the internet. Tests to verify the quality of the nitrogen atmosphere were performed using the lighter test and niobium pentachloride (NbCl5), which is a moisture/oxygen sensitive material. The results demonstrated that the equipment is able to maintain an inert atmosphere for several hours, does not permit lighter to function and maintains the NbCl5 stable.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68269044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170945
Iara Silva, Michel Chaves, A. Brito, A. Nogueira, Sidney de Lima
MOLECULAR FOSSILS FROM SILURIAN ORGANIC MATTER OF THE TIANGUÁ FORMATION (PARNAÍBA BASIN), NORTHEASTERN BRAZIL: PALEOENVIRONMENTAL IMPLICATIONS AND THERMAL MATURATION. The Parnaíba Basin covers an area of 665,888 km2 between the northern and northeastern regions of Brazil. It is completely made up of siliciclastic sedimentary and volcanic rocks with ages varying between the Silurian and the Cretaceous. Among the formations of the Basin, the Tianguá Formation is considered a potential source rock. However, there are few geochemical and/or geological studies and no research work on the molecular parameters of the organic matter (OM) present in its outcropping rocks (OR). Thus, the objective of the present work is to characterize the OM, concerning the depositional paleoenvironment and the degree of thermal evolution, through molecular parameters and OM content. The OM was extracted using the Soxhlet system, chromatographed by classical methods, and analyzed using GC-MS and GC-MS/MS. The samples exhibited low total organic carbon values (TOC <1) and the molecular parameters of saturated and aromatic hydrocarbons suggested a marine depositional environment, with algae, bacteria, and terrestrial plants input. The C30 biomarkers (24-n-propylcholestane), identified using synthetic standards and usually associated with the Chrysophyte algae, corroborated the marine origin of the depositional environment. In addition, some molecular parameters suggested little thermal evolution.
{"title":"FÓSSEIS MOLECULARES DA MATÉRIA ORGÂNICA SILURIANA DA FORMAÇÃO TIANGUÁ (BACIA DO PARNAÍBA), NORDESTE DO BRASIL: IMPLICAÇÕES PALEOAMBIENTAIS E MATURAÇÃO TÉRMICA","authors":"Iara Silva, Michel Chaves, A. Brito, A. Nogueira, Sidney de Lima","doi":"10.21577/0100-4042.20170945","DOIUrl":"https://doi.org/10.21577/0100-4042.20170945","url":null,"abstract":"MOLECULAR FOSSILS FROM SILURIAN ORGANIC MATTER OF THE TIANGUÁ FORMATION (PARNAÍBA BASIN), NORTHEASTERN BRAZIL: PALEOENVIRONMENTAL IMPLICATIONS AND THERMAL MATURATION. The Parnaíba Basin covers an area of 665,888 km2 between the northern and northeastern regions of Brazil. It is completely made up of siliciclastic sedimentary and volcanic rocks with ages varying between the Silurian and the Cretaceous. Among the formations of the Basin, the Tianguá Formation is considered a potential source rock. However, there are few geochemical and/or geological studies and no research work on the molecular parameters of the organic matter (OM) present in its outcropping rocks (OR). Thus, the objective of the present work is to characterize the OM, concerning the depositional paleoenvironment and the degree of thermal evolution, through molecular parameters and OM content. The OM was extracted using the Soxhlet system, chromatographed by classical methods, and analyzed using GC-MS and GC-MS/MS. The samples exhibited low total organic carbon values (TOC <1) and the molecular parameters of saturated and aromatic hydrocarbons suggested a marine depositional environment, with algae, bacteria, and terrestrial plants input. The C30 biomarkers (24-n-propylcholestane), identified using synthetic standards and usually associated with the Chrysophyte algae, corroborated the marine origin of the depositional environment. In addition, some molecular parameters suggested little thermal evolution.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68267884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170950
Mengbo Zhou, Chunyu Sun, Hong Zhao
Reducing non-specific adsorption of proteins on the surface of magnetic nanoparticles (MNPs) is becoming increasingly important. In this paper, we proposed a novel surface modification procedure by grafting hyperbranched polyglycerol (HPG) onto the surface of MNPs (Fe3O4@SiO2@MAA), in which lots of hydroxyl groups from HPG not only provide the hydrates sheath to prevent non-specific adsorption of proteins, but also react with succinic anhydride to generate carboxyl groups that serve as active sites to specifically bind proteins. The protein adsorption experiments showed that the non-specific adsorption (0.07 μg mg-1) was reduced to 4.58% of that before modification. It also showed that the antigen binding capacity was 9.7 times higher than the original when detecting cardiac troponin I (cTnI) in human plasma samples, which indicated that the final synthesized MNPs had great application prospects in bio-separation and bioanalysis.
{"title":"REDUCING NON-SPECIFIC ADSORPTION OF PROTEINS VIA THE HPG MODIFICATION ON THE SURFACE OF MAGNETIC NANOPARTICLES","authors":"Mengbo Zhou, Chunyu Sun, Hong Zhao","doi":"10.21577/0100-4042.20170950","DOIUrl":"https://doi.org/10.21577/0100-4042.20170950","url":null,"abstract":"Reducing non-specific adsorption of proteins on the surface of magnetic nanoparticles (MNPs) is becoming increasingly important. In this paper, we proposed a novel surface modification procedure by grafting hyperbranched polyglycerol (HPG) onto the surface of MNPs (Fe3O4@SiO2@MAA), in which lots of hydroxyl groups from HPG not only provide the hydrates sheath to prevent non-specific adsorption of proteins, but also react with succinic anhydride to generate carboxyl groups that serve as active sites to specifically bind proteins. The protein adsorption experiments showed that the non-specific adsorption (0.07 μg mg-1) was reduced to 4.58% of that before modification. It also showed that the antigen binding capacity was 9.7 times higher than the original when detecting cardiac troponin I (cTnI) in human plasma samples, which indicated that the final synthesized MNPs had great application prospects in bio-separation and bioanalysis.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170952
H. Vieira, A. Figueiredo, Murilo Souza, M. Canela
EVALUATION OF AROMATIC VOLATILE ORGANIC COMPOUNDS IN THE ATMOSPHERE IN CAMPOS DOS GOYTACAZES AND ITAPERUNA APPLYING MULTIVARIATE DATA ANALYSIS. Volatile Organic Compounds (VOCs) are air pollutants emitted from different sources, mainly by industries and motor vehicles. The evaluation of the emission of these compounds into the atmosphere should be done systematically and with a varied class of compounds. The large number of data generated during the monitoring of these VOCs requires the use of multivariate data tools to interpret the results. In this sense, this work aimed to monitor 10 aromatic VOCs present in the atmosphere of the largest cities in the Norte Fluminense (Campos dos Goytacazes) and Noroeste Fluminense (Itaperuna) regions. The VOCs were actively sampled and analyzed by gas chromatography with mass spectrometry detection after thermal desorption. After treatment of analytical results, it was observed that in both cities there is influence of vehicular emissions. In the city of Itaperuna, due to the relief and lower dispersion of contaminants, there is a higher occurrence of photochemical reactions. The exploratory analysis of the data allowed identifying the variables that were more significant and correlating these variables with the main sources of emission of the compounds. This is the first study of VOCs evaluation in Campos dos Goytacazes and Itaperuna, demonstrating the relevance of this research for understanding the behavior of VOCs in these cities, which have different reliefs and high traffic of cars and trucks in the studied sites.
应用多变量数据分析评价校园中大气中芳香族挥发性有机物的含量。挥发性有机化合物(VOCs)是来自不同来源的空气污染物，主要由工业和机动车辆排放。对这些化合物排放到大气中的评价应系统地、用不同种类的化合物进行。这些VOCs监测过程中产生的大量数据需要使用多变量数据工具来解释结果。从这个意义上说，这项工作旨在监测北弗鲁米嫩塞(Campos dos Goytacazes)和北弗鲁米嫩塞(Itaperuna)地区最大城市大气中存在的10种芳香性VOCs。对挥发性有机化合物进行主动取样，热解吸后采用气相色谱-质谱法进行分析。对分析结果进行处理后发现，两个城市均存在机动车尾气排放的影响。在伊塔佩鲁纳市，由于污染物的缓解和较低的分散，光化学反应的发生率较高。数据的探索性分析允许识别更重要的变量，并将这些变量与化合物的主要排放源相关联。这是首个对Campos dos Goytacazes和Itaperuna进行VOCs评价的研究，证明了本研究对了解这些城市VOCs行为的相关性，这些城市在研究地点有不同的缓解和高车流量的汽车和卡车。
{"title":"AVALIAÇÃO DE COMPOSTOS ORGÂNICOS VOLÁTEIS AROMÁTICOS NA ATMOSFERA EM CAMPOS DOS GOYTACAZES E ITAPERUNA APLICANDO A ANÁLISE MULTIVARIADA DE DADOS","authors":"H. Vieira, A. Figueiredo, Murilo Souza, M. Canela","doi":"10.21577/0100-4042.20170952","DOIUrl":"https://doi.org/10.21577/0100-4042.20170952","url":null,"abstract":"EVALUATION OF AROMATIC VOLATILE ORGANIC COMPOUNDS IN THE ATMOSPHERE IN CAMPOS DOS GOYTACAZES AND ITAPERUNA APPLYING MULTIVARIATE DATA ANALYSIS. Volatile Organic Compounds (VOCs) are air pollutants emitted from different sources, mainly by industries and motor vehicles. The evaluation of the emission of these compounds into the atmosphere should be done systematically and with a varied class of compounds. The large number of data generated during the monitoring of these VOCs requires the use of multivariate data tools to interpret the results. In this sense, this work aimed to monitor 10 aromatic VOCs present in the atmosphere of the largest cities in the Norte Fluminense (Campos dos Goytacazes) and Noroeste Fluminense (Itaperuna) regions. The VOCs were actively sampled and analyzed by gas chromatography with mass spectrometry detection after thermal desorption. After treatment of analytical results, it was observed that in both cities there is influence of vehicular emissions. In the city of Itaperuna, due to the relief and lower dispersion of contaminants, there is a higher occurrence of photochemical reactions. The exploratory analysis of the data allowed identifying the variables that were more significant and correlating these variables with the main sources of emission of the compounds. This is the first study of VOCs evaluation in Campos dos Goytacazes and Itaperuna, demonstrating the relevance of this research for understanding the behavior of VOCs in these cities, which have different reliefs and high traffic of cars and trucks in the studied sites.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170957
Guilherme Borges, Pedro Borges, C. Cardoso, D. Cerqueira
ALTERNATIVE MICROSCOPES BUILT USING LOW-COST MATERIALS. This work aims to compare the construction of magnification devices. Details of the construction and use of microscopes based on webcam and smartphone are presented, using software for image processing. It is also presented the construction of microscopes using drops of different liquids as magnifying lens, a compound microscope, and a water-drop projector. Magnified images obtained with each device are presented, and the different microscopes are compared. The results obtained from the use of these alternative instruments confirm that alternative microscopes are instruments of easy reproducibility, enabling the amplification of samples for a more detailed observation of the object of interest.
{"title":"MICROSCÓPIOS ALTERNATIVOS CONSTRUÍDOS A PARTIR DE MATERIAIS DE BAIXO CUSTO","authors":"Guilherme Borges, Pedro Borges, C. Cardoso, D. Cerqueira","doi":"10.21577/0100-4042.20170957","DOIUrl":"https://doi.org/10.21577/0100-4042.20170957","url":null,"abstract":"ALTERNATIVE MICROSCOPES BUILT USING LOW-COST MATERIALS. This work aims to compare the construction of magnification devices. Details of the construction and use of microscopes based on webcam and smartphone are presented, using software for image processing. It is also presented the construction of microscopes using drops of different liquids as magnifying lens, a compound microscope, and a water-drop projector. Magnified images obtained with each device are presented, and the different microscopes are compared. The results obtained from the use of these alternative instruments confirm that alternative microscopes are instruments of easy reproducibility, enabling the amplification of samples for a more detailed observation of the object of interest.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68268637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170944
S. Machado, Carlos Cortes, R. Almada
MINIMUM CURRICULUM VERSUS NATIONAL COURSE GUIDELINES: DIVERGENT PATHS IN THE TRAINING OF PROFESSIONALS IN CHEMISTRY. The professional practice of chemist is defined by Ordinary Resolution no 1,511 of 1975, edited by the Federal Council of Chemistry. This legislation is outdated and not in line with the National Curricular Guidelines for chemistry courses, approved by the National Council of Education in 2001. This situation has greatly hampered the training of future chemistry professional and the modernization of undergraduate courses and must be urgently corrected by those responsible for formulating the legislation that defines the chemistry courses. Thus, we understand that the time has come for the Federal Council of Chemistry, Scientific Societies and Universities to work together to solve this problem, modernizing the legislation that defines the attributions of the chemistry professionals and defining the necessary profile for their professional practice in the XXI century.
{"title":"CURRÍCULO MÍNIMO VERSUS DIRETRIZES NACIONAIS DE CURSO: CAMINHOS DIVERGENTES NA FORMAÇÃO DOS PROFISSIONAIS DA QUÍMICA","authors":"S. Machado, Carlos Cortes, R. Almada","doi":"10.21577/0100-4042.20170944","DOIUrl":"https://doi.org/10.21577/0100-4042.20170944","url":null,"abstract":"MINIMUM CURRICULUM VERSUS NATIONAL COURSE GUIDELINES: DIVERGENT PATHS IN THE TRAINING OF PROFESSIONALS IN CHEMISTRY. The professional practice of chemist is defined by Ordinary Resolution no 1,511 of 1975, edited by the Federal Council of Chemistry. This legislation is outdated and not in line with the National Curricular Guidelines for chemistry courses, approved by the National Council of Education in 2001. This situation has greatly hampered the training of future chemistry professional and the modernization of undergraduate courses and must be urgently corrected by those responsible for formulating the legislation that defines the chemistry courses. Thus, we understand that the time has come for the Federal Council of Chemistry, Scientific Societies and Universities to work together to solve this problem, modernizing the legislation that defines the attributions of the chemistry professionals and defining the necessary profile for their professional practice in the XXI century.","PeriodicalId":49641,"journal":{"name":"Quimica Nova","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68267826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-03DOI: 10.21577/0100-4042.20170956
V. Fonseca, S. Rodrigues, M. Pazinato
THE CURRICULUMS OF THE FIRST CHEMISTRY COURSES AT UNIVERSITY OF COIMBRA AND BRAZILIAN UNIVERSITIES. The study of History of Education is very important to teacher education because it allows reflections and greater criticality about their own teaching practice and professional condition. The purpose of this research was to identify similarities between the curriculum of Chemistry courses of University of Coimbra (UC), National School of Chemistry (ENQ) and School of Engineering of Porto Alegre (EEPA) at the beginning of the 20th century seeking to identify possible influences of UC in the structuring and curriculum of the first Brazilian higher education Chemistry courses. The results showed more similarities regarding the structure between UC and ENQ, while there were greater correspondences in the curricular activities between UC and EEPA. Finally, it was not possible to identify confluences in the curriculums of the courses over the decades since there was a divergence between the models of organization of the higher education in the countries under study.
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