L. A. Trujillo, J. Santos, Nuria Calero, M. C. Alfaro, José Muñoz
Se estudian las propiedades reologicas de una suspoemulsion comercial para uso agroquimico. Se comparan los resultados obtenidos mediante curvas de flujo y ensayos en cizalla oscilatoria de baja amplitud para cinco temperaturas distintas en el intervalo de 5 a 25oC. Las curvas de flujo, ponen de manifiesto que la suspoemulsion se caracteriza por presentar un comportamiento pseudoplastico, menos acusado a medida que aumenta la temperatura, que se ajusta al modelo de Sisko. Barridos de esfuerzo realizados a 0,1Hz permiten determinar el reducido rango viscoelastico lineal de la suspoemulsion, que depende de la temperatura. Los espectros mecanicos, entre 3Hzy 0,01 Hz, revelan que el sistema manifiesta propiedades viscoelasticas con un comportamiento tipico de gel debil. La aparicion de un minimo en el valor de G” respecto a la frecuencia ha permitido estimar el modulo plateau, el cual desciende con el aumento de temperatura segun una ecuacion tipo Arrhenius. Aun asi, la suspoemulsion presenta un caracter elastico que favorece su estabilidad fisica con el tiempo de almacenamiento. Se ha demostrado ademas que el sistema no sigue la regla de Cox-Merz.
{"title":"Caracterización reológica de una suspoemulsión comercial para uso agroquímico","authors":"L. A. Trujillo, J. Santos, Nuria Calero, M. C. Alfaro, José Muñoz","doi":"10.13140/2.1.2364.2244","DOIUrl":"https://doi.org/10.13140/2.1.2364.2244","url":null,"abstract":"Se estudian las propiedades reologicas de una suspoemulsion comercial para uso agroquimico. Se comparan los resultados obtenidos mediante curvas de flujo y ensayos en cizalla oscilatoria de baja amplitud para cinco temperaturas distintas en el intervalo de 5 a 25oC. Las curvas de flujo, ponen de manifiesto que la suspoemulsion se caracteriza por presentar un comportamiento pseudoplastico, menos acusado a medida que aumenta la temperatura, que se ajusta al modelo de Sisko. Barridos de esfuerzo realizados a 0,1Hz permiten determinar el reducido rango viscoelastico lineal de la suspoemulsion, que depende de la temperatura. Los espectros mecanicos, entre 3Hzy 0,01 Hz, revelan que el sistema manifiesta propiedades viscoelasticas con un comportamiento tipico de gel debil. La aparicion de un minimo en el valor de G” respecto a la frecuencia ha permitido estimar el modulo plateau, el cual desciende con el aumento de temperatura segun una ecuacion tipo Arrhenius. Aun asi, la suspoemulsion presenta un caracter elastico que favorece su estabilidad fisica con el tiempo de almacenamiento. Se ha demostrado ademas que el sistema no sigue la regla de Cox-Merz.","PeriodicalId":7709,"journal":{"name":"Afinidad","volume":"70 1","pages":"51-56"},"PeriodicalIF":0.3,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66244072","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 : 2011-04-20DOI: 10.5012/JKCS.2011.55.2.230
M. Soliman, S. El-Sakka
The present study describes the synthesis of 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives. The synthesis of the first target compound, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone(1), was achieved by Friedel-Crafts acylation of o-cresylmethyl ether with succinic anhydride and subsequent cyclization of the intermediary g-keto acid with hydrazine hydrate. Condensation compound 1 with aromatical dehydes in the presence of sodium ethoxide affords the corresponding 4-substituted benzyl pyridazinones(3a-d). The pyridazinone 1 under went dehydrogenation upon treatment with bromine/acetic acid mixture to give (4). Pyridazine (5) has been synthesized upon the reaction of pyridazinone (1) with 1,3-diphenyl-2-propen-1-one under the Michael addition reaction. N-dialkylaminomethyl derivatives 6a-b have been obtained from the reaction of pyridazinone 1 with formaldehyde and secondary amine, whereas reaction of 1 with formaldehyde gives N-hydroxymethyl derivative (7). This study also includes the synthesis of the 3-chloro pyridazinone derivative 8 in excellent yield by heating pyridazinone 3b in phosphorus oxychloride. The behaviour of the chloro derivative toward sodium azide, benzyl amine and anthranilic acid was also studied. The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence.
{"title":"Synthesis of some new 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives","authors":"M. Soliman, S. El-Sakka","doi":"10.5012/JKCS.2011.55.2.230","DOIUrl":"https://doi.org/10.5012/JKCS.2011.55.2.230","url":null,"abstract":"The present study describes the synthesis of 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives. The synthesis of the first target compound, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone(1), was achieved by Friedel-Crafts acylation of o-cresylmethyl ether with succinic anhydride and subsequent cyclization of the intermediary g-keto acid with hydrazine hydrate. Condensation compound 1 with aromatical dehydes in the presence of sodium ethoxide affords the corresponding 4-substituted benzyl pyridazinones(3a-d). The pyridazinone 1 under went dehydrogenation upon treatment with bromine/acetic acid mixture to give (4). Pyridazine (5) has been synthesized upon the reaction of pyridazinone (1) with 1,3-diphenyl-2-propen-1-one under the Michael addition reaction. N-dialkylaminomethyl derivatives 6a-b have been obtained from the reaction of pyridazinone 1 with formaldehyde and secondary amine, whereas reaction of 1 with formaldehyde gives N-hydroxymethyl derivative (7). This study also includes the synthesis of the 3-chloro pyridazinone derivative 8 in excellent yield by heating pyridazinone 3b in phosphorus oxychloride. The behaviour of the chloro derivative toward sodium azide, benzyl amine and anthranilic acid was also studied. The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence.","PeriodicalId":7709,"journal":{"name":"Afinidad","volume":"231 1","pages":"316-319"},"PeriodicalIF":0.3,"publicationDate":"2011-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70592430","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 : 2010-01-01DOI: 10.1590/2224-6185.2010.3.%X
René Viera Bertrán, D. Álvarez, A. P. Hernández
En este trabajo se presento un modelo tipo caja negra que proporcionaba una relacion explicita entre la fraccion del reactante solido no convertido I; y la relacion Y = t/τ. Ademas, se presento un conjunto de aplicaciones posibles, para sistemas con flujo en piston para la fase solida. Se deducen las expresiones correspondientes a situaciones de mayor complejidad, tales como: reactores con mezclado perfecto para la fase solida, las cuales se tratan en las situaciones siguientes: Un solo reactor con tiempo de residencia medio: tp; particulas de un solo tamano; mezcla de particulas de diferentes tamanos; para dos reactores con tiempos de residencia medio Iguales (tp); para tres reactores con tiempos de residencia medio Iguales (tp); para cuatro reactores con tiempos de residencia medio Iguales (tp); para cinco reactores con tiempos de residencia medio Iguales (tp). El procedimiento empleado en las deducciones, puede ser utilizado en otras situaciones de interes sin mayores dificultades. Las expresiones presentadas, ademas de su facilidad de uso, presentan la ventaja de facilitar la confeccion de algoritmos programables. Palabras clave: paso controlante, difusion interna, fluido- solido no catalitico. In the first part of this paper, a black box model that provided an explicit relationship between the fraction of unconverted solid reactant I and the relationship Y = t /τ. You had a set of possible applications, for systems with plug flow for the solid phase. In this second part of the work, we deduce the expressions for more complex situations, such as perfect mixing reactor to the solid phase, which are discussed in the situations described below: a single reactor mean residence time: tp; particles of one size; mixture of particles of different sizes; for two reactors with residence times equal means (tp); for three reactors with residence times equal means (tp); for four reactors with residence times equal means (tp); for five reactor residence times equal means (tp)
本文提出了一个黑匣子模型，该模型提供了未转化固体反应物I的分数之间的明确关系;y = t/τ的关系。此外，还提出了一套可能的应用，用于固相活塞流系统。推导了更复杂情况下的表达式，如:具有完美固相混合的反应器，在以下情况下处理:具有平均停留时间的单反应器:tp;单一大小的粒子;混合不同大小的颗粒;对于两个平均停留时间(tp)相等的反应堆;对于三个平均停留时间(tp)相等的反应堆;四个平均停留时间(tp)相等的反应堆;对于5个平均停留时间(tp)相等的反应堆。在扣除中使用的程序可以毫无困难地用于其他利益情况。所提出的表达式除了易于使用外，还具有易于编写可编程算法的优点。关键词:控制步骤，内扩散，流体-非催化固体。In the first part of this paper, a black box提供model that an明确relationship between the fraction of unconverted solid reactant and the relationship I = t /τ。= =地理= =根据美国人口普查，这个县的面积为。在本工作的第二部分中，我们推导出更复杂情形的表达式，例如在以下情形中讨论的固体相的完美混合反应器:一种尺寸的粒子;不同大小颗粒的混合物;对于居住时间相等的两个反应堆;居住时间相等的三个反应堆;4个居住时间相等的反应堆;对于5个反应堆住宅时间相等的平均值(tp)
{"title":"EXPRESIÓN EN SISTEMAS FLUIDO-SÓLIDO NO CATALÍTICOS, CONTROLADOS POR LA DIFUSIÓN INTERNA EN PARTÍCULAS DE TAMAÑO FIJO. SEGUNDA PARTE","authors":"René Viera Bertrán, D. Álvarez, A. P. Hernández","doi":"10.1590/2224-6185.2010.3.%X","DOIUrl":"https://doi.org/10.1590/2224-6185.2010.3.%X","url":null,"abstract":"En este trabajo se presento un modelo tipo caja negra que proporcionaba una relacion explicita entre la fraccion del reactante solido no convertido I; y la relacion Y = t/τ. Ademas, se presento un conjunto de aplicaciones posibles, para sistemas con flujo en piston para la fase solida. Se deducen las expresiones correspondientes a situaciones de mayor complejidad, tales como: reactores con mezclado perfecto para la fase solida, las cuales se tratan en las situaciones siguientes: Un solo reactor con tiempo de residencia medio: tp; particulas de un solo tamano; mezcla de particulas de diferentes tamanos; para dos reactores con tiempos de residencia medio Iguales (tp); para tres reactores con tiempos de residencia medio Iguales (tp); para cuatro reactores con tiempos de residencia medio Iguales (tp); para cinco reactores con tiempos de residencia medio Iguales (tp). El procedimiento empleado en las deducciones, puede ser utilizado en otras situaciones de interes sin mayores dificultades. Las expresiones presentadas, ademas de su facilidad de uso, presentan la ventaja de facilitar la confeccion de algoritmos programables. Palabras clave: paso controlante, difusion interna, fluido- solido no catalitico. In the first part of this paper, a black box model that provided an explicit relationship between the fraction of unconverted solid reactant I and the relationship Y = t /τ. You had a set of possible applications, for systems with plug flow for the solid phase. In this second part of the work, we deduce the expressions for more complex situations, such as perfect mixing reactor to the solid phase, which are discussed in the situations described below: a single reactor mean residence time: tp; particles of one size; mixture of particles of different sizes; for two reactors with residence times equal means (tp); for three reactors with residence times equal means (tp); for four reactors with residence times equal means (tp); for five reactor residence times equal means (tp)","PeriodicalId":7709,"journal":{"name":"Afinidad","volume":"30 1","pages":"20-30"},"PeriodicalIF":0.3,"publicationDate":"2010-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67306878","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 : 2008-12-01DOI: 10.21608/ABSB.2008.10502
I. S. A. Hafiz, S. Baker, A. Hussein
2-Aminopyridine was fused with ethyl acetoacetate without solvent for two hours to yield the N-2-pyridyl–3-oxobutanamide 1. However, when the reaction time was increased to 5 hours a structure 3 was obtained. Condensation of the structure 3 with benzaldehyde gave 4. The reaction of pyridopyridone 3 with arylidenemalononitrile7a-c afforded 4 H-pyran derivative 10a-c. In contrast to the behavior of arylidenemalononitrile 7a-c towards pyridopyridine3, benzylidenemalononitrile 7d reacted withcompound 3 to give a product 11. Compound 1 was allowed to react with arylidenemalononitrile to give the dihydropyridine derivative 17a-d. Alkylation of compound 1 with alkylating agents has been also reported. Thus, compound 1 was condensed with [DMF-DMA] in refluxing dioxane to yield 18, but under the reaction conditions we obtained only 21. The pyridopyridone 3 reacted with benzoylisothiocyanate 25a,b to give thiourea derivatives 26a,b Cyclization of 26a,b in dry dioxane and conc. sulphuric acid afforded pyridopyrimidinethione derivatives 27a,b. On the other hand, coupling of pyridopyridine 3 with the aromatic diazonium salt 28a-e afforded the corresponding azo products 29a-e. Boiling of compound 29 in aqueous solution of HCl afforded the hydrazo products 30. Treatmentof arylhydrazone 30a with malononitrile afforded the pyridazine derivatives 31.
{"title":"Utility of N-2-pyridyl-3-oxobutanamide in heterocyclic synthesis: Synthesis of new dihydropyridine, fused pyridine, pyridopyridine, pyridazine and pyridopyrimidinethione derivatives","authors":"I. S. A. Hafiz, S. Baker, A. Hussein","doi":"10.21608/ABSB.2008.10502","DOIUrl":"https://doi.org/10.21608/ABSB.2008.10502","url":null,"abstract":"2-Aminopyridine was fused with ethyl acetoacetate without solvent for two hours to yield the N-2-pyridyl–3-oxobutanamide 1. However, when the reaction time was increased to 5 hours a structure 3 was obtained. Condensation of the structure 3 with benzaldehyde gave 4. The reaction of pyridopyridone 3 with arylidenemalononitrile7a-c afforded 4 H-pyran derivative 10a-c. In contrast to the behavior of arylidenemalononitrile 7a-c towards pyridopyridine3, benzylidenemalononitrile 7d reacted withcompound 3 to give a product 11. Compound 1 was allowed to react with arylidenemalononitrile to give the dihydropyridine derivative 17a-d. Alkylation of compound 1 with alkylating agents has been also reported. Thus, compound 1 was condensed with [DMF-DMA] in refluxing dioxane to yield 18, but under the reaction conditions we obtained only 21. The pyridopyridone 3 reacted with benzoylisothiocyanate 25a,b to give thiourea derivatives 26a,b Cyclization of 26a,b in dry dioxane and conc. sulphuric acid afforded pyridopyrimidinethione derivatives 27a,b. On the other hand, coupling of pyridopyridine 3 with the aromatic diazonium salt 28a-e afforded the corresponding azo products 29a-e. Boiling of compound 29 in aqueous solution of HCl afforded the hydrazo products 30. Treatmentof arylhydrazone 30a with malononitrile afforded the pyridazine derivatives 31.","PeriodicalId":7709,"journal":{"name":"Afinidad","volume":"67 1","pages":"65-71"},"PeriodicalIF":0.3,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68374869","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}
{"title":"Synthesis of some new spiropyrazolo[4',5':5,6]-pyrano[2,3-d]pyrimidines","authors":"M. Al-Thebeiti","doi":"10.3987/COM-99-8797","DOIUrl":"https://doi.org/10.3987/COM-99-8797","url":null,"abstract":"","PeriodicalId":7709,"journal":{"name":"Afinidad","volume":"57 1","pages":"365-370"},"PeriodicalIF":0.3,"publicationDate":"2000-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3987/COM-99-8797","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70615091","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}
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