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Brazilian Journal of Thermal Analysis最新文献

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INFLUÊNCIA DA RELAÇÃO NCO/OH NO ESTUDO DO COMPORTAMENTO TÉRMICO DO POLIURETANO DERIVADO DE ÓLEO VEGETAL NCO/OH比对植物油衍生聚氨酯热行为研究的影响
Brazilian Journal of Thermal Analysis Pub Date : 2014-04-16 DOI: 10.18362/BJTA.V3I1-2.19
Antonia Marli dos Santos, S. C. Neto, G. O. Chierice
{"title":"INFLUÊNCIA DA RELAÇÃO NCO/OH NO ESTUDO DO COMPORTAMENTO TÉRMICO DO POLIURETANO DERIVADO DE ÓLEO VEGETAL","authors":"Antonia Marli dos Santos, S. C. Neto, G. O. Chierice","doi":"10.18362/BJTA.V3I1-2.19","DOIUrl":"https://doi.org/10.18362/BJTA.V3I1-2.19","url":null,"abstract":"Os poliuretanos sao polimeros cuja polimerizacao ocorre pela reacao dos grupos isocianatos (NCO) com grupos hidroxilas (OH). Geralmente os poliuretanos se apresenta na forma bicomponente que podem ser um pre-polimero contendo grupos NCO livre e um poliol contendo grupos hidroxilas livre. Neste trabalho e feito um estudo do comportamento de um poliuretano derivado de oleo vegetal, bicomponente polimerizado com diferentes relacoes NCO/OH utilizando as tecnicas de analise termica (TG/DTG), juntamente a espectrometria de absorcao na regiao do infravermelho. Amostras de poliuretano derivado do oleo de mamona com diferentes relacoes de NCO/OH.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"20 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91277713","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
Thermal behavior of malonic acid, sodium malonate and its compounds with some bivalent transition metal ions in dynamic N2 and CO2 atmospheres 丙二酸、丙二酸钠及其化合物与某些二价过渡金属离子在动态N2和CO2气氛中的热行为
Brazilian Journal of Thermal Analysis Pub Date : 2014-04-03 DOI: 10.18362/BJTA.V2I1.4
F. Caires, Danilo José Coura Gomes, Andréa Cristina Gigante, L. S. Lima, Claudio Teodoro Carvalho, M. Ionashiro
{"title":"Thermal behavior of malonic acid, sodium malonate and its compounds with some bivalent transition metal ions in dynamic N2 and CO2 atmospheres","authors":"F. Caires, Danilo José Coura Gomes, Andréa Cristina Gigante, L. S. Lima, Claudio Teodoro Carvalho, M. Ionashiro","doi":"10.18362/BJTA.V2I1.4","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.4","url":null,"abstract":"Thermal stability and thermal decomposition of malonic acid, sodium malonate and its compounds with Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC) in N 2 and CO 2 atmospheres and TG-FTIR in N 2 atmosphere. The thermal decomposition of malonic acid occurs with decarboxylation followed by the formation of acetic acid in both atmospheres. For sodium malonate the thermal decomposition occurs with formation of sodium carbonate, and for the transition metal malonates the final residue was: MnO (N 2 , CO 2 ),FeO (N 2 ), Fe 3 O 4 (CO 2 ), Co + CoO (N 2 ), CoO (CO 2 ), Ni (N 2 , CO 2 ), Cu (N 2 , CO 2 ) and ZnO (N 2 , CO 2 ).","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"85 1","pages":"12-16"},"PeriodicalIF":0.0,"publicationDate":"2014-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88780272","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: 3
Synthesis, characterization and thermal behavior of solid state 2-methoxybenzylidenepyruvate of alkali earth metals, except beryllium and radium 碱土金属(除铍和镭外)固态2-甲氧基苄基丙酮酸酯的合成、表征和热行为
Brazilian Journal of Thermal Analysis Pub Date : 2014-04-03 DOI: 10.18362/BJTA.V2I1.5
Luis Henrique Bembo Filho, E. Y. Ionashiro, Claudio Teodoro Carvalho, A. B. Siqueira
{"title":"Synthesis, characterization and thermal behavior of solid state 2-methoxybenzylidenepyruvate of alkali earth metals, except beryllium and radium","authors":"Luis Henrique Bembo Filho, E. Y. Ionashiro, Claudio Teodoro Carvalho, A. B. Siqueira","doi":"10.18362/BJTA.V2I1.5","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.5","url":null,"abstract":"Solid state M(2-MeO-BP) 2 compounds, where M stands for bivalent alkali earth metal ions (Mg, Ca, Srand Ba) and 2-MeO-BP is 2-methoxybenzylidenepyruvate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy, elemental analysis and complexometry, were used to investigate these compounds. The dehydration of magnesium, strontium and barium compounds occurs in a single step, while for calcium compound the dehydration occurs in two steps. The thermal decomposition of the anhydrous compounds occurs with the formation of carbonate as intermediate, except for the magnesium compound. The results also provided information about the composition, coordination mode, thermal behaviour and thermal decomposition of isolated compounds.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"42 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2014-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84071711","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
Synthesis, Characterization and Thermal Behavior of Solid-State Compounds of Light Trivalent Lanthanide Malonates 轻三价丙二酸镧系固体化合物的合成、表征及热行为
Brazilian Journal of Thermal Analysis Pub Date : 2014-04-03 DOI: 10.18362/BJTA.V2I1.6
J. R. Locatelli, E. Y. Ionashiro, F. Caires, C. T. Carvalho
{"title":"Synthesis, Characterization and Thermal Behavior of Solid-State Compounds of Light Trivalent Lanthanide Malonates","authors":"J. R. Locatelli, E. Y. Ionashiro, F. Caires, C. T. Carvalho","doi":"10.18362/BJTA.V2I1.6","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.6","url":null,"abstract":"In this study, compounds of hydrated lanthanide malonates were synthesized by precipitation of sodium malonates ion. Quantitative studies of the compounds obtained in the solid state, as well as the thermal behavior of these compounds were performed by thermal analysis (TG-DTA and DSC). Additional complementary studies were also performed using X-ray diffraction by the powder method (XRD), Evolved Gas Analysis (EGA) and complexometric titration with EDTA. Thus, the compounds synthesized in this work, ranging from lanthanum to gadolinium, were studied mainly in relation to their thermal properties, enabling to establish the stoichiometry, the decomposition steps and identify by EGA the main volatile products released during the decomposition. The qualitative study by XRD and FT-IR showed that the compounds were obtained in the crystalline state and metal-ligand coordination occurs by bidentate bonding and /or bridge, respectively. The interest in these compounds is due to the several applications of malonate ion, such as  industrial and biological, not to mention that the coordination of the lanthanide ions to the malonate ligand can provide them new properties which could be studied and explored forward.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"237 1","pages":"23-30"},"PeriodicalIF":0.0,"publicationDate":"2014-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80373977","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: 4
Determination of calcium in tablets containing calcium citrate using thermogravimetry (TG) 热重法测定柠檬酸钙片中的钙含量
Brazilian Journal of Thermal Analysis Pub Date : 2014-04-03 DOI: 10.18362/BJTA.V2I1.7
E. G. Araújo, F. E. Morais, E. Santos, C. Martínez-Huitle, Márcia Gorette Lima da Silva, S. P. M. C. Souza, N. S. Fernandes
{"title":"Determination of calcium in tablets containing calcium citrate using thermogravimetry (TG)","authors":"E. G. Araújo, F. E. Morais, E. Santos, C. Martínez-Huitle, Márcia Gorette Lima da Silva, S. P. M. C. Souza, N. S. Fernandes","doi":"10.18362/BJTA.V2I1.7","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.7","url":null,"abstract":"The present study utilized thermogravimetry (TG) and optical emission spectroscopy with inductively coupled plasma (ICP/OES) to determine the amount of calcium in calcium citrate tablets, which are used for the treatment of osteoporosis. The samples were characterized using Fourier transform infrared spectroscopy (FTIR), termogravimetry/derivative thermogravimetry (TG/DTG), differential thermal analysis (DTA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). In the DTA and DSC curves obtained, both endo- and exothermic events were observed, which are indicative of dehydration and decomposition, respectively. The X-ray diffractograms showed that the samples present crystallinity. Additionally, peaks observed in the X-ray diffractograms indicate the presence of a calcium hydroxide residue due to the reaction between calcium oxide with moisture in the air. The calcium content obtained by TG from the tablet sample (17.77%) was similar to that obtained using ICP-OES (16.84%).","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"49 1","pages":"17-22"},"PeriodicalIF":0.0,"publicationDate":"2014-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81032653","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: 8
Uso de curvas termogravimétricas para a determinação do teor de mineralização em hidrogéis 利用热重曲线测定水凝胶中矿化含量
Brazilian Journal of Thermal Analysis Pub Date : 2013-12-23 DOI: 10.18362/BJTA.V2I1.12
M. M. Horn, Márcio Nunes De Paula, V. Martins, A. M. G. Plepis
{"title":"Uso de curvas termogravimétricas para a determinação do teor de mineralização em hidrogéis","authors":"M. M. Horn, Márcio Nunes De Paula, V. Martins, A. M. G. Plepis","doi":"10.18362/BJTA.V2I1.12","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.12","url":null,"abstract":"Os hidrogeis tem sido estudados para aplicacoes biomedicas, como em sistemas de liberacao de farmacos e em engenharia de tecidos. Os materiais contendo fosfato de calcio tem sido frequentemente utilizados para a substituicao e reconstituicao de defeitos osseos. Assim, este trabalho descreve a obtencao de hidrogeis mineralizados e sua posterior caracterizacao. A quantificacao do teor de mineralizacao foi determinada por termogravimetria, sendo encontrados valores em torno de 40% de calcificacao, que corresponde a valores de residuo a 750 o C. Os resultados por EDX e raios-X indicam que o fosfato de calcio depositado e hidroxiapatita estequiometrica e que os cristais estao distribuidos na superficie dos hidrogeis.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"51 1","pages":"50-54"},"PeriodicalIF":0.0,"publicationDate":"2013-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77748508","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
Effect of hydrochloric acid in different concentrations and temperatures up to some properties of organic cassava starch 不同浓度和温度的盐酸对有机木薯淀粉某些性质的影响
Brazilian Journal of Thermal Analysis Pub Date : 2013-12-20 DOI: 10.18362/BJTA.V2I1.8
L. P. Cordoba, L. S. Ribeiro, T. Colman, Cristina Soltovski de Oliveira, M. M. P. Andrade, F. J. O. G. D. Costa, E. Schnitzler
{"title":"Effect of hydrochloric acid in different concentrations and temperatures up to some properties of organic cassava starch","authors":"L. P. Cordoba, L. S. Ribeiro, T. Colman, Cristina Soltovski de Oliveira, M. M. P. Andrade, F. J. O. G. D. Costa, E. Schnitzler","doi":"10.18362/BJTA.V2I1.8","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.8","url":null,"abstract":"The main objective of the present work was to study the thermal properties and rheological behavior of natural and modified organic cassava starch with standard solutions of hydrochloric acid in concentrations 0.1 and 0.2 mol L -1 and in temperatures 25 and 45oC, respectively, as well as verify the structural changes up to the surface of granules. The results allowed us to establish the relationship between the viscosity (RVA), the thermal properties (TG-DTA, DSC) and changes in the morphology of granules (NC-AFM). The major modifications in all the studied properties of the starch granules occurs in those treated with standard HCl at room temperature (25 oC), proportionally to higher concentrations.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"1 1","pages":"6-11"},"PeriodicalIF":0.0,"publicationDate":"2013-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86543138","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: 13
Preparation, characterization and thermal decomposition of sodium and potassium salts of dithiocarbamate 二硫代氨基甲酸钠、钾盐的制备、表征及热分解
Brazilian Journal of Thermal Analysis Pub Date : 2013-12-18 DOI: 10.18362/BJTA.V2I1.11
L. A. Ramos, É. Cavalheiro
{"title":"Preparation, characterization and thermal decomposition of sodium and potassium salts of dithiocarbamate","authors":"L. A. Ramos, É. Cavalheiro","doi":"10.18362/BJTA.V2I1.11","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.11","url":null,"abstract":"Pyrrolidinedithiocarbamate (Pyr), piperidinedithiocarbamate (Pip), morpholinedithiocarbamate (Mor), diethanolaminedithiocarbamate (DEDC) and hexamethylenedithiocarbamate (Hex) sodium and potassium salts, were synthesized, characterized by IR, elemental analysis, 1 H and 13 C NMR and their thermal behaviors were investigated using thermogravimetry (TG) and differential scanning calorimetry (DSC). The decomposition of sodium salts occurred in different manner depending on the nature of the substituent, generating sodium polysulphides. The potassium salts decomposed via thiocyanate as predicted in the literature.Pyrrolidinedithiocarbamate (Pyr), piperidinedithiocarbamate (Pip), morpholinedithiocarbamate (Mor), diethanolaminedithiocarbamate (DEDC) and hexamethylenedithiocarbamate (Hex) sodium and potassium salts, were synthesized, characterized by IR, elemental analysis, 1 H and 13 C NMR and their thermal behaviors were investigated using thermogravimetry (TG) and differential scanning calorimetry (DSC). The decomposition of sodium salts occurred in different manner depending on the nature of the substituent, generating sodium polysulphides. The potassium salts decomposed via thiocyanate as predicted in the literature.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"22 1","pages":"38-44"},"PeriodicalIF":0.0,"publicationDate":"2013-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73860515","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: 11
Solid state thermal and spectroscopic studies on the antibiotic amoxicillin trihydrate 三水合阿莫西林抗生素的固态热光谱研究
Brazilian Journal of Thermal Analysis Pub Date : 2013-12-18 DOI: 10.18362/BJTA.V2I1.10
D. Gálico, R. B. Guerra, A. O. Legendre, E. Schnitzler, R. Mendes, G. Bannach
{"title":"Solid state thermal and spectroscopic studies on the antibiotic amoxicillin trihydrate","authors":"D. Gálico, R. B. Guerra, A. O. Legendre, E. Schnitzler, R. Mendes, G. Bannach","doi":"10.18362/BJTA.V2I1.10","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.10","url":null,"abstract":"Thermogravimetry (TG), differential thermal analysis (DTA), differential scanning calorimetry (DSC) and Fourier transformed infrared spectroscopy (IR) were used to study amoxicillin trihydrate. The thermal behavior and physical properties of the studied compound were established and coupled TG-IR analyses were used to suggest some decomposition products. In this investigation, quantum chemical approach was used to determine the molecular structures using Becke three-parameter hybrid method and the Lee–Yang–Par (LYP) correlation functional. The performed molecular calculations in this work were done using the Gaussian 09 routine. The theoretical calculations helped us interpret the IR spectra, which supply structural and physicochemical information.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"71 1","pages":"45-49"},"PeriodicalIF":0.0,"publicationDate":"2013-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84283684","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: 6
Comportamento térmico do fármaco e do medicamento contendo Cetoprofeno
Brazilian Journal of Thermal Analysis Pub Date : 2013-12-18 DOI: 10.18362/BJTA.V2I1.9
Auriel Guedes Pompeu, Andréia Peraro-Nascimento, Lazaro Moscardini D’ Assunção
{"title":"Comportamento térmico do fármaco e do medicamento contendo Cetoprofeno","authors":"Auriel Guedes Pompeu, Andréia Peraro-Nascimento, Lazaro Moscardini D’ Assunção","doi":"10.18362/BJTA.V2I1.9","DOIUrl":"https://doi.org/10.18362/BJTA.V2I1.9","url":null,"abstract":"O Cetoprofeno e um farmaco antiinflamatorio nao-esteroide (AINE) com alto poder analgesico e propriedades anti-reumaticas. O objetivo deste trabalho foi estudar o comportamento termico do farmaco Cetoprofeno e suas possiveis interacoes com os excipientes Estearato de Magnesio e Lactose, bem como do medicamento, utilizando-se das curvas TG-DTA e DSC destes compostos isoladamente e de misturas dos mesmos. A Termogravimetria e a Calorimetria Exploratoria Diferencial tem sido metodos alternativos muito uteis no estudo de possiveis interacoes entre os componentes (farmaco e excipientes) de um medicamento, na determinacao do ponto de fusao, na avaliacao de polimorfismo e da pureza de um farmaco, apesar de nao ser preconizado pela Farmacopeia Brasileira. Os metodos termoanaliticos usados mostraram que o Cetoprofeno analisado e puro e que ha compatibilidade com a lactose, sendo necessario o uso de outras tecnicas, como absorcao na regiao do infravermelho e difratometria de raios X, para verificar a compatibilidade deste farmaco com o excipiente Estearato de magnesio.","PeriodicalId":9282,"journal":{"name":"Brazilian Journal of Thermal Analysis","volume":"40 1","pages":"31-37"},"PeriodicalIF":0.0,"publicationDate":"2013-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86986879","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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