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Conhecimento geológico do material mineral uma contribuição para arqueologia: conceitos e características petrográficas 矿物的地质知识对考古学的贡献:岩石学的概念和特征
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-05-31 DOI: 10.56814/pecen.v7i1.1915
T. Garrido
{"title":"Conhecimento geológico do material mineral uma contribuição para arqueologia: conceitos e características petrográficas","authors":"T. Garrido","doi":"10.56814/pecen.v7i1.1915","DOIUrl":"https://doi.org/10.56814/pecen.v7i1.1915","url":null,"abstract":"Arenito, calcário, flint, mármore, granito, gnaisse e obsidiana, são pedras frequentemente mencionadas na literatura tendo sido utilizadas há milhares de anos como material para a fabricação de objetos, utensílios, ferramentas e edificações.Este trabalho aborda a matéria-prima geológica utilizada em tempos primórdios da vida do homem primitivo, tem o objetivo de esclarecer a natureza mineral, conceitos e características petrográficas. Trata-se de artefatos líticos constituídos de rochas, minerais silicosos, e mineralóides, de estruturas cristalina, microcristalina, criptocristalina e amorfa. Esses materiais possuem natureza coesa, dureza alta (± 7, escala Mohs), grande resistência à alteração e fraturamento em lascas, assim, representaram importantes elementos para várias aplicações. São mencionados, ainda, os materiais pétreos das primeiras edificações e objetos domésticos de argila e cerâmica. Soma-se ao trabalho a caracterização dos pigmentos inorgânicos em ocres, provenientes de óxi-hidróxidos de metais observados em pinturas rupestres. Tais materiais pétreos e metálicos foram efetivamente frequentes e significativos, e representam uma oportunidade potencial de se estudar as transformações vivenciadas pelos povos primitivos.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78017033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Uso do tucumã (Astrocaryum aculeatumMeyer) em cosmético: caracterização química e elaboração de sabonetes artesanais tucuma (Astrocaryum aculeatumMeyer)在化妆品中的应用:手工肥皂的化学特性和制备
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-05-31 DOI: 10.56814/pecen.v7i1.1925
Edriely Vilena de Oliveira, Ruandra Kaienne da Silva Laranjeira, K. Yamaguchi
{"title":"Uso do tucumã (Astrocaryum aculeatumMeyer) em cosmético: caracterização química e elaboração de sabonetes artesanais","authors":"Edriely Vilena de Oliveira, Ruandra Kaienne da Silva Laranjeira, K. Yamaguchi","doi":"10.56814/pecen.v7i1.1925","DOIUrl":"https://doi.org/10.56814/pecen.v7i1.1925","url":null,"abstract":"A Amazônia apresenta inúmeras frutas nativas com potencial econômico, tecnológico, nutricional e de sabores e aromas inigualáveis, dentre eles o tucumã. O objetivo deste artigo foi determinar as características química das cascas e cascas do tucumã e elaborar um sabonete artesanal utilizando essa matéria prima. Foi realizado a prospecção fitoquímica clássica e a determinação do perfil químico por cromatografia em camada delgada associado a análise da capacidade antioxidante e elaboração de sabonetes artesanais. A partir do produto, foram realizados testes físico-químicos e análise sensorial. Detectou-se a presença de substâncias fenólicas e catequina e capacidade antioxidante no extrato das cascas e polpa. Na análise físico-química, os sabonetes apresentaram cremosidade, emoliencia e uma boa aceitação dos provadores. Este estudo abre a perspectiva de agregar valor a casca de tucumã e do uso integral para utilização industrial e de forma sustentável do fruto.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85501966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Some comments on radiobiological models and the consistent Taylor series model. 关于放射生物学模型和一致泰勒级数模型的几点评论。
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-05-31 DOI: 10.56814/pecen.v7i1.1987
G. Alvarez, D. Lobão
{"title":"Some comments on radiobiological models and the consistent Taylor series model.","authors":"G. Alvarez, D. Lobão","doi":"10.56814/pecen.v7i1.1987","DOIUrl":"https://doi.org/10.56814/pecen.v7i1.1987","url":null,"abstract":"","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88102098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical Simulation of the Production of Core-Shell Microparticles 核-壳微粒生成的数值模拟
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-04-28 DOI: 10.5433/1679-0375.2023.v44.47206
C. Fernandes, L. L. Ferrás, A. Afonso
{"title":"Numerical Simulation of the Production of Core-Shell Microparticles","authors":"C. Fernandes, L. L. Ferrás, A. Afonso","doi":"10.5433/1679-0375.2023.v44.47206","DOIUrl":"https://doi.org/10.5433/1679-0375.2023.v44.47206","url":null,"abstract":"Conventional methods that are commonly used for the preparation of microbubble delivery systems include sonication, high-shear emulsification, and membrane emulsification. However, these methods present significant disadvantages, namely, poor control over the particle size and distribution. To date, engineering core-shell microparticles remains a challenging task. Thus, there is a demand for new techniques that can enable control over the size, composition, stability, and uniformity of microparticles. Microfluidic techniques offer great advantages in the fabrication of microparticles over the conventional processes because they require mild and inert processing conditions. In this work, we present a numerical study based on the finite volume method, for the development of capsules by considering the rheological properties of three phases, air, a perfluorohexane (C6 F14) and a polymeric solution constituted of a solution of 0.25% w/v alginate. This methodology allows studying the stability and behavior of microparticles under different processing conditions.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47537135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Bench X-ray microtomography of water-salt solution/oil injected into samples of the Botucatu formation boucatu地层水盐溶液/油注入样品的台式x射线显微层析成像
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-01-18 DOI: 10.5433/1679-0375.2022v43n2p199
L. C. Marques, C. Appoloni
{"title":"Bench X-ray microtomography of water-salt solution/oil injected into samples of the Botucatu formation","authors":"L. C. Marques, C. Appoloni","doi":"10.5433/1679-0375.2022v43n2p199","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p199","url":null,"abstract":"This paper provides a report on the utilization of the X-ray microtomography to obtain images of the internal microstructure of natural sandstone samples from the Botucatu Formation. Its primary objective was to identify the different phases of fluids when injected into the samples to evaluate the various phases through grayscale histograms obtained from 2-D images, quantification of fluid phases, and generation of 3-D images of them. The fluids used in the experiments comprised one type of commercial oil, one type of industrial oil, and an water-salt solution. Quantitative results from 2-D and 3-D analyzes are presented and compared to the volume of injected solution and the measured volume. The phase size distributions indicated which pore radii had a more relevant participation in the percolation of fluids through the samples. Projections in conjunction with 2-D images and profiles of average percentages of air-filled pores indicated the occurrence of preferential percolation flow paths.  The 2-D images allowed the measurement of the contact angle between the phases present in the sample containing industrial oil. Different measurements taken from the sample containing commercial oil showed capillary effects indicated by the average percentage profiles of air-filled pores in the 2-D images.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48552000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Why much of Chemistry may be indisputably non-bonded? 为什么很多化学物质都是无键的?
Semina Ciencias Exatas e Tecnologicas Pub Date : 2023-01-18 DOI: 10.5433/1679-0375.2022v43n2p211
B. G. Oliveira
{"title":"Why much of Chemistry may be indisputably non-bonded?","authors":"B. G. Oliveira","doi":"10.5433/1679-0375.2022v43n2p211","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p211","url":null,"abstract":"In this compendium, the wide scope of all intermolecular interactions ever known has been revisited, in particular giving emphasis the capability of much of the elements of the periodic table to form non-covalent contacts. Either hydrogen bonds, dihydrogen bonds, halogen bonds, pnictogen bonds, chalcogen bonds, triel bonds, tetrel bonds, regium bonds, spodium bonds or even the aerogen bond interactions may be cited. Obviously that experimental techniques have been used in some works, but it was through the theoretical methods that these interactions were validate, wherein the QTAIM integrations and SAPT energy partitions have been useful in this regard. Therefore, the great goal concerns to elucidate the interaction strength and if the intermolecular system shall be total, partial or non-covalently bonded, wherein this last one encompasses the most majority of the intermolecular interactions what leading to affirm that chemistry is debatably non-bonded.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46190045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Short text classification applied to item description: Some methods evaluation 短文本分类在项目描述中的应用:一些评价方法
Semina Ciencias Exatas e Tecnologicas Pub Date : 2022-12-30 DOI: 10.5433/1679-0375.2022v43n2p189
Gilsiley Henrique Darú, Felipe Daltrozo da Motta Motta, Antonio Castelo, G. Loch
{"title":"Short text classification applied to item description: Some methods evaluation","authors":"Gilsiley Henrique Darú, Felipe Daltrozo da Motta Motta, Antonio Castelo, G. Loch","doi":"10.5433/1679-0375.2022v43n2p189","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p189","url":null,"abstract":"The increasing demand for information classification based on content in the age of social media and e-commerce has led to the need for automated product classification using their descriptions. This study aims to evaluate various techniques for this task, with a focus on descriptions written in Portuguese. A pipeline is implemented to preprocess the data, including lowercasing, accent removal, and unigram tokenization. The bag of words method is then used to convert text into numerical data, and five classification techniques are applied: argmaxtf, argmaxtfnorm, argmaxtfidf from information retrieval, and two machine learning methods logistic regression and support vector machines. The performance of each technique is evaluated using simple accuracy via thirty-fold cross validation. The results show that logistic regression achieves the highest mean accuracy among the evaluated techniques.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43427979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Interferência da densidade de áreas verdes e da frequência de veículos nos níveis de pressão sonora: estudo de caso em Irati, Paraná 绿地密度和车辆频率对声压级的干扰:Irati案例研究，parana
Semina Ciencias Exatas e Tecnologicas Pub Date : 2022-12-30 DOI: 10.5433/1679-0375.2022v43n2p179
André de Souza Toniolo, Paulo Costa de Oliveira Filho, K. G. Martins, Juliana De Conto
{"title":"Interferência da densidade de áreas verdes e da frequência de veículos nos níveis de pressão sonora: estudo de caso em Irati, Paraná","authors":"André de Souza Toniolo, Paulo Costa de Oliveira Filho, K. G. Martins, Juliana De Conto","doi":"10.5433/1679-0375.2022v43n2p179","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p179","url":null,"abstract":"O ruído é um problema da sociedade moderna e um poluente ambiental causado por atividades industriais, de tráfego, entre outras, podendo gerar problemas à saúde. Neste contexto, esse trabalho tem por finalidade avaliar o potencial de áreas verdes urbanas como barreira atenuadora de ruídos. Para isto, foi realizada uma análise de proximidade entre amostras de ruído mensurados em 10 locais da área urbana considerando a densidade de áreas verdes e a densidade de tráfego de veículos. Foi realizado o mapeamento por classe de níveis de tráfego urbano, das áreas verdes, no entorno de 10 pontos amostrais e calculadas as respectivas taxas de áreas verdes com uso de imagens orbitais de alta resolução espacial. Para as mesmas áreas foram calculadas densidades de tráfego urbano. Foi avaliada a influência atenuadora de ruídos devido a presença de maiores ou menores taxas de áreas verdes urbanas, caracterizadas como áreas verdes arbóreas e que possam funcionar como barreiras verticais verdes atenuadoras de ruídos, como também a interferência da frequência de veículos em função da densidade de tráfego veicular. Desta forma, buscou-se relações estatísticas entre os níveis de ruído encontrados e seus diferentes graus de urbanização. Os resultados demonstraram que as altas frequências de veículos, tanto a 100 como a 250 metros de proximidade dos pontos amostrais, influenciaram com maior intensidade de ruído e que as áreas verdes arbóreas reduziram marginalmente, porém tal redução não foi significativa.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43981040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Carbonation of concretes containing LC³ cements with different supplementary materials 含有不同补充材料的LC³水泥的混凝土碳化
Semina Ciencias Exatas e Tecnologicas Pub Date : 2022-12-27 DOI: 10.5433/1679-0375.2022v43n2p161
C. Balestra, Gustavo Savaris, A. Y. Nakano, Ricardo Schneider
{"title":"Carbonation of concretes containing LC³ cements with different supplementary materials","authors":"C. Balestra, Gustavo Savaris, A. Y. Nakano, Ricardo Schneider","doi":"10.5433/1679-0375.2022v43n2p161","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p161","url":null,"abstract":"Due to the clinkerization process during the Portland cement production, large amounts of CO2 are emitted, increasing the effects related to climate change (approximately 5-10% of global CO2 emissions come from cement production), consequently, the seek for alternatives to mitigate these high emissions are necessary. The use of supplementary cementitious materials (SCM) to partial replace of Portand clinker/cement has been the subject of different research, including the use of LC3 cements (Limestone Calcined Clay Cements), where up to 50% of Portland clinker can be replaced, however, cement industry has already used othersupplementary cementitious materials with pozzolanic activities in commercial cements. In this sense, this work evaluates the performance of concretes containing LC3 mixtures with the presence of different SCM (silica fume, fly ash, sugarcane bagasse ash and açaí stone ash) regarding durability issues by carbonation. The results showed that all concretes with LC3 presented higher carbonation fronts in relation to the reference concrete, with Portland cement, due to the lower availability of calcium to react with the CO2 that penetrates into the concrete pores, so the adoption of curing procedures and coatings are recommended.","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44543097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An app for monitoring the population of Golden Mussels 一个监控金贻贝数量的应用程序
Semina Ciencias Exatas e Tecnologicas Pub Date : 2022-12-27 DOI: 10.5433/1679-0375.2022v43n2p171
Ricardo Vinicius Gonçalves Rosas, A. R. Costa, C. M. Dias, Charles H. X. B. Barbosa, José C. R. Silva, D. Pastore, R. Figueira
{"title":"An app for monitoring the population of Golden Mussels","authors":"Ricardo Vinicius Gonçalves Rosas, A. R. Costa, C. M. Dias, Charles H. X. B. Barbosa, José C. R. Silva, D. Pastore, R. Figueira","doi":"10.5433/1679-0375.2022v43n2p171","DOIUrl":"https://doi.org/10.5433/1679-0375.2022v43n2p171","url":null,"abstract":"This work shows the construction of a simple, functional and real-time application to estimate the population dynamics of the Golden Mussel, an invasive species that has been causing great ecological and economic damage, particularly to the electricity sector by obstructing water collection routes of hydroelectric plant equipment. The tool Golden Mussel App, developed with Shiny package of the R©, programming language, aims to enable professionals engaged in harm reduction in the energy generation sector to follow the temporal evolution of populations, even without advanced knowledge about the mathematical modeling of the problem. In this way, the application configures itself as an auxiliary tool in the planning of actions to control the Golden Mussel","PeriodicalId":30173,"journal":{"name":"Semina Ciencias Exatas e Tecnologicas","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43448898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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