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Id: biblio-951808
Autor: Zhang, Sen; Song, Ping; Li, Shuang.
Título: Application of n-dodecane as an oxygen vector to enhance the activity of fumarase in recombinant Escherichia coli: role of intracellular microenvironment
Fonte: Braz. j. microbiol;49(3):662-667, July-Sept. 2018. tab, graf.
Idioma: en.
Projeto: Natural Science Foundation of Jiangsu Province; . National science fund for colleges and universities in Jiangsu Province.
Resumo: Abstract The effect of the intracellular microenvironment in the presence of an oxygen vector during expression of a fusion protein in Escherichia coli was studied. Three organic solutions at different concentration were chosen as oxygen vectors for fumarase expression. The addition of n-dodecane did not induce a significant change in the expression of fumarase, while the activity of fumarase increased significantly to 124% at 2.5% n-dodecane added after 9 h induction. The concentration of ATP increased sharply during the first 6 h of induction, to a value 7600% higher than that in the absence of an oxygen-vector. NAD/NADH and NADP/NADPH ratios were positively correlated with fumarase activity. n-Dodecane can be used to increase the concentration of ATP and change the energy metabolic pathway, providing sufficient energy for fumarase folding.
Descritores: Oxigênio/metabolismo
Expressão Gênica
Alcanos/metabolismo
Escherichia coli/genética
Fumarato Hidratase/metabolismo
-Oxigênio/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Proteínas Recombinantes/química
Dobramento de Proteína
Alcanos/química
Escherichia coli/metabolismo
Fumarato Hidratase/genética
Fumarato Hidratase/química
NADP/metabolismo
NADP/química
Responsável: BR1.1 - BIREME


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Id: biblio-871485
Autor: Peixoto, Tatiana Vasconcelos.
Título: Aumento de células T CD4+CD69+ e redução de células T reguladoras CD4+CD25+FoxP3+ em camundongos com Lúpus Eritematoso Sistêmico (LES) induzido por pristane / Increase of CD4+CD69+ T cells and reduction of CD4+CD25+FoxP3+ regulatory T cells in pristane-induced mice with systemic lupus erythematosus (SLE).
Fonte: São Paulo; s.n; 2015. [88] p. ilus, tab, graf.
Idioma: pt.
Tese: Apresentada a Universidade de São Paulo. Faculdade de Medicina para obtenção do grau de Doutor.
Resumo: Introdução: O Lúpus Eritematoso Sistêmico (LES) é uma doença autoimune multissistêmica de etiologia complexa que envolve fatores ambientais, genéticos e hormonais. É caracterizada pela produção de autoanticorpos e mediadores inflamatórios, ativação e proliferação de células T autorreativas e perda da autotolerância imunológica. Em pacientes com LES, a expressão do receptor primário de ativação CD69 é aumentada e a de células T supressoras/reguladoras (Treg) CD4+CD25+FoxP3+ é reduzida. O CD69 é essencial para ativação de células T CD4 autorreativas enquanto que as células Treg são importantes na manutenção da autotolerância. Desta forma, células T tem um papel central na patogênese do LES, mas os mecanismos implicados na falência da autotolerância ainda não são elucidados, destacando a importância de estudos em modelos experimentais da doença, como o de LES-induzido por pristane. Objetivo: Quantificar células T CD4+CD69+ ativadas e Treg CD4+CD25+FoxP3+ no sangue, baço e LP de camundongos Balb/c LESinduzido por pristane no sentido de avaliar a falência de autotolerância neste modelo. Métodos: Analisamos 84 camundongos Balb/c fêmeas: 52 receberam por via intraperitoneal uma dose única de 0,5 ml de pristane e 32 a mesma dose de salina. Amostras de sangue, baço e LP dos camundongos eutanasiados foram coletadas 90, 120, 180 e 300 (T90, T120, T180 e T300) dias após a inoculação de pristane ou salina. Células mononucleares do sangue periférico (CMSP), do LP (CMLP) e esplenócitos foram obtidos por lise das hemácias seguida de lavagens com RPMI medium 1640 e centrifugação, e posteriormente criopreservadas até a avaliação por citometria de fluxo usando o aparelho Guava EasyCyteTM HT (Millipore). Para esta etapa, as células foram descongeladas, lavadas com RPMI medium 1640 e incubadas com anticorpos monoclonais dirigidos contra CD3, CD4, CD25, CD28, CD69, CTLA-4, FoxP3, CD14 e Ly6C (BD PharmingenTM). Os resultados foram expressos como média ± DP e teste de...

Introduction: Systemic Lupus Erythematosus (SLE) is multisystemic autoimmune disease with complex etiology that involves environmental, genetic and hormonal factors. Is characterized by auto-antibodies and inflammatory mediators production, autoreactive T cells activation and proliferation and loss of immunogenic autotolerance. In patients with SLE, expression of CD69 activation primary receptor is increased and the CD4+CD25+FoxP3+ suppressor/regulatory T cell (Treg) is reduced. CD69 is essential for activation of autoreactive CD4 T cells while Treg cells are important in autotolerance maintenance. In this way, T cells have a central role in the pathogenesis of SLE however, the mechanisms implied in the autotolerance failure are still not elucidated, highlighting the importance of studies in this disease's experimental models, such as pristane-induced SLE. Objective: Quantify activated CD4+CD69+ T cells and CD4+CD25+FoxP3+ Treg in blood, spleen and peritoneal lavage (PL) of Balb/c mice with pristane-induced SLE in order to evaluate autotolerance failure in this model. Methods: 84 female Balb/c mice were analyzed: 52 received a single intraperitoneal 0,5 ml dose of pristane and 32 the same dose of saline. Euthanized mice samples of blood, spleen and peritoneal lavage were collected 90, 120, 180 and 300 (T90, T120, T180 and T300) days after inoculation of pristane or saline. Mononuclear cells from peripheral blood (PBMC), PL (PLMC) and splenocytes were obtained by lysis of erythrocytes followed by washings with RPMI medium 1640 and centrifugation, subsequently criopreserved until evaluation by flow cytometry using the appliance GuavaEasyCyteTM HT (Millipore). For this step, cells were unfrozen, washed with RPMI medium 1640 and incubated with monoclonal antibodies against CD3, CD4, CD25, CD28, CD69, CTLA-4, FoxP3, CD14 and Ly6C (BD PharmingenTM). The results were expressed as mean ± SD and Mann-Whitney 11 test was used for statistical analysis, being considered...
Descritores: Alcanos
Doenças Autoimunes
LINFOCITOS T CDABBREVIATIONS AS TOPIC-POSITIVOS
Lúpus Eritematoso Sistêmico/etiologia
Camundongos
Linfócitos T Reguladores
Limites: Animais
Feminino
Camundongos
Responsável: BR66.1 - Divisão de Biblioteca e Documentação
BR66.1


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Id: lil-710935
Autor: Ashraf, Sadaf Naz; Zubair, Muhammad; Rizwan, Komal; Tareen, Rasool Bakhsh; Rasool, Nasir; Zia-Ul-Haq, Muhammad; Ercisli, Sezai.
Título: Compositional studies and Biological activities of Perovskia abrotanoides Kar. oils
Fonte: Biol. Res;47:1-9, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Current study has been designed to evaluate the chemical composition of essential and fixed oils from stem and leaves of Perovskia abrotanoides and antioxidant and antimicrobial activities of these oils. RESULTS: GC-MS analysis of essential oil identified 19 compounds with (E)-9-dodecenal being the major component in stem and hexadecanoic acid in leaves. In contrast, GC-MS analysis of fixed oil showed 40 constituents with α-amyrin the major component in stem and α-copaene in leaves. The antioxidant activity showed the highest value of 76.7% in essential oil from leaves in comparison with fixed oil from stem (45.9%) through inhibition of peroxidation in linoleic acid system. The antimicrobial assay tested on different microorganisms (e.g. E. coli, S. aureus, B. cereus, Nitrospira, S. epidermis, A. niger, A. flavus and C. albicans) showed the higher inhibition zone at essential oil from leaves (15.2 mm on B. cereus) as compared to fixed oil from stem (8.34 mm onS. aureus) and leaves (11.2 mm on S. aureus). CONCLUSIONS: The present study revealed the fact that essential oil analyzed from Perovskia abrotanoides stem and leaves could be a promising source of natural products with potential antioxidant and antimicrobial activities, as compared to fixed oil.
Descritores: Anti-Infecciosos/química
Antioxidantes/química
Lamiaceae/química
Folhas de Planta/química
Óleos Vegetais/farmacologia
Caules de Planta/química
-Alcanos/análise
Alcanos/farmacologia
Anti-Infecciosos/farmacologia
Antioxidantes/farmacologia
Aspergillus/efeitos dos fármacos
Bacillus cereus/efeitos dos fármacos
Candida albicans/efeitos dos fármacos
Testes de Sensibilidade a Antimicrobianos por Disco-Difusão
Escherichia coli/efeitos dos fármacos
Cromatografia Gasosa-Espectrometria de Massas
Peroxidação de Lipídeos/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Éteres Metílicos/análise
Éteres Metílicos/farmacologia
Óleos Voláteis/química
Ácido Oleanólico/análise
Ácido Oleanólico/análogos & derivados
Ácido Oleanólico/farmacologia
Ácido Palmítico/análise
Ácido Palmítico/farmacologia
Triterpenos Pentacíclicos/análise
Triterpenos Pentacíclicos/farmacologia
Óleos Vegetais/química
Substâncias Redutoras/análise
Sesquiterpenos/análise
Sesquiterpenos/farmacologia
Staphylococcus/efeitos dos fármacos
Ácidos Esteáricos/análise
Ácidos Esteáricos/farmacologia
Responsável: CL1.1 - Biblioteca Central


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Id: lil-688595
Autor: Procópio, Luciano; Silva, Michele de Cassia Pereira e; Elsas, Jan Dirk van; Seldin, Lucy.
Título: Transcriptional profiling of genes involved in n-hexadecane compounds assimilation in the hydrocarbon degrading Dietzia cinnamea P4 strain
Fonte: Braz. j. microbiol;44(2):639-647, 2013. ilus, graf, tab.
Idioma: en.
Resumo: The petroleum-derived degrading Dietzia cinnamea strain P4 recently had its genome sequenced and annotated. This allowed employing the data on genes that are involved in the degradation of n-alkanes. To examine the physiological behavior of strain P4 in the presence of n-alkanes, the strain was grown under varying conditions of pH and temperature. D. cinnamea P4 was able to grow at pH 7.0-9.0 and at temperatures ranging from 35 ºC to 45 ºC. Experiments of gene expression by real-time quantitative RT-PCR throughout the complete growth cycle clearly indicated the induction of the regulatory gene alkU (TetR family) during early growth. During the logarithmic phase, a large increase in transcriptional levels of a lipid transporter gene was noted. Also, the expression of a gene that encodes the protein fused rubredoxin-alkane monooxygenase was enhanced. Both genes are probably under the influence of the AlkU regulator.
Descritores: Actinomycetales/genética
Actinomycetales/metabolismo
Alcanos/metabolismo
Perfilação da Expressão Gênica
Genes Bacterianos
Hidrocarbonetos/metabolismo
Redes e Vias Metabólicas/genética
-Actinomycetales/crescimento & desenvolvimento
Biotransformação
Concentração de Íons de Hidrogênio
Reação em Cadeia da Polimerase em Tempo Real
Temperatura
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-685498
Autor: Memorias do Instituto Oswaldo Cruz; Calderon-Fernandez, Gustavo Mario; Juarez, Marta Patricia.
Título: The cuticular hydrocarbons of the Triatoma sordida species subcomplex (Hemiptera: Reduviidae)
Fonte: Mem. Inst. Oswaldo Cruz;108(6):778-784, set. 2013. graf.
Idioma: en.
Projeto: ANPCYT.
Resumo: The cuticular hydrocarbons of the Triatoma sordida subcomplex (Hemiptera: Reduviidae: Triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. They comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from C21-C33 and represented 33-45% of the hydrocarbon fraction; n-C29 was the major component. Methyl-branched alkanes showed alkyl chains from C24-C43. High molecular weight dimethyl and trimethylalkanes (from C35-C39) represented most of the methyl-branched fraction. A few tetramethylalkanes were also detected, comprising mostly even-numbered chains. Several components such as odd-numbered 3-methylalkanes, dimethylalkanes and trimethylalkanes of C37 and C39 showed patterns of variation that allowed the differentiation of the species and populations studied. Triatoma guasayana and Triatoma patagonica showed the most distinct hydrocarbon patterns within the subcomplex. The T. sordida populations from Brazil and Argentina showed significantly different hydrocarbon profiles that posed concerns regarding the homogeneity of the species. Triatoma garciabesi had a more complex hydrocarbon pattern, but it shared some similarity with T. sordida. The quantitative and qualitative variations in the cuticular hydrocarbons may help to elucidate the relationships between species and populations of this insect group.
Descritores: Hidrocarbonetos/isolamento & purificação
Lipídeos/isolamento & purificação
Triatoma/química
-Análise de Variância
Alcanos/análise
Cromatografia Gasosa-Espectrometria de Massas/métodos
Limites: Animais
Feminino
Masculino
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-637764
Autor: Adebusoye, Sunday A; Amund, Olukayode O; Ilori, Matthew O; Domeih, Dupe O; Okpuzor, Joy.
Título: Growth and biosurfactant synthesis by Nigerian hydrocarbon-degrading estuarine bacteria
Fonte: Rev. biol. trop;56(4):1603-1611, Dec. 2008. graf, tab.
Idioma: en.
Resumo: The ability of microorganisms to degrade petroleum hydrocarbons is important for finding an environmentally-friendly method to restoring contaminated environmental matrices. Screening of hydrocarbon-utilizing and biosurfactant-producing abilities of organisms from an estuarine ecosystem in Nigeria, Africa, resulted in the isolation of five microbial strains identified as Corynebacterium sp. DDv1, Flavobacterium sp. DDv2, Micrococcus roseus DDv3, Pseudomonas aeruginosa DDv4 and Saccharomyces cerevisae DDv5. These isolates grew readily on several hydrocarbons including hexadecane, dodecane, crude oil and petroleum fractions. Axenic cultures of the organisms utilized diesel oil (1.0 % v/v) with generation times that ranged significantly (t-test, P < 0.05) between 3.25 and 3.88 day, with concomitant production of biosurfactants. Kinetics of growth indicates that biosurfactant synthesis occurred predominantly during exponential growth phase, suggesting that the bioactive molecules are primary metabolites. Strains DDv1 and DDv4 were evidently the most metabolically active in terms of substrate utilization and biosurfactant synthesis compared to other strains with respective emulsification index of 63 and 78 %. Preliminary biochemical characterization indicates that the biosurfactants are heteropolymers consisting of lipid, protein and carbohydrate moieties. The hydrocarbon catabolic properties coupled with biosurfactant-producing capabilities is an asset that could be exploited for cleanup of oil-contaminated matrices and also in food and cosmetic industries. Rev. Biol. Trop. 56 (4): 16031611. Epub 2008 December 30.

La capacidad de los microorganismos para degradar hidrocarburos del petróleo es de gran importancia para hallar un método aceptable y ambientalmente amigable para la restauración de terrenos ambientalmente contaminados. Al investigar las capacidades de los organismos de un ecosistema de estuario que utilizan hidrocarburos y producen biosurfactantes, se produjo como resultado el aislamiento de cinco cepas microbianas identificadas como Corynebacterium sp. DDv1, Flavobacterium sp. DDv2, Micrococcus roseus DDv3, Pseudomonas aeruginosa y DDv4 Saccharomyces cerevisiae DDv5. Estas cepas crecieron fácilmente en varios hidrocarburos incluyendo hexadecanos, dodecanos, petróleo crudo y fracciones de petróleo. Los cultivos axénicos de organismos utilizaron diesel (1.0% v/v) con períodos por generación con ámbitos significativos (t-test, P <0.05) de entre 3.25 y 3.88 días, con la consiguiente producción de bio-surfactantes. La cinética del crecimiento indica que la síntesis de bio-surfactante se produjo principalmente durante la fase de crecimiento exponencial, lo que sugiere que las moléculas bioactivas son metabolitos primarios. Las cepas DDv1 y DDv4 fueron evidentemente las más metabólicamente activas en términos de utilización del sustrato y la síntesis de bio-surfactantes en comparación con otras cepas con índices respectivos de emulsificación de 63 y 78%. La caracterización bioquímica preliminar indica que los bio-surfactantes son heteropolímeros constituidos de fracciones de lípidos, proteínas y carbohidratos. Las propiedades catabólicas de los hidrocarburos, junto con las capacidades de producción de bio-surfactantes, es una ventaja que puede ser aprovechada para la limpieza de terrenos contaminados con petróleo y también en la industria alimentaria y cosmética.
Descritores: Bactérias Gram-Negativas/metabolismo
Bactérias Gram-Positivas/metabolismo
Petróleo/metabolismo
Saccharomyces/metabolismo
Tensoativos/metabolismo
-Alcanos/metabolismo
Biodegradação Ambiental
Bactérias Gram-Negativas/crescimento & desenvolvimento
Bactérias Gram-Positivas/crescimento & desenvolvimento
Nigéria
Saccharomyces/crescimento & desenvolvimento
Fatores de Tempo
Responsável: CR1.1 - BINASSS - Biblioteca Nacional de Salud y Seguridad Social


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Id: lil-522157
Autor: Gottemukkala, Vijay V; Saripella, Kalyan K; Kadari, Anil K; Neau, Steven H.
Título: Effect of methyl branching of C8H18 alkanes and water activity on lipase-catalyzed enantioselective esterification of ibuprofen
Fonte: Electron. j. biotechnol;11(1):13-25, Jan. 2008. ilus, graf, tab.
Idioma: en.
Projeto: NIH.
Resumo: The purpose of this research was to study the effect of the methyl branching of a high log P alkane solvent and the water activity in the organic medium on the initial rate and the enantioselectivity of ibuprofen esterification catalyzed by Candida rugosa lipase. Resolution of ibuprofen is important because S-(+)-ibuprofen has the desired pharmacological activity, whereas the R-(-)-enantiomer causes much of the side effects. The Candida rugosa lipase-catalyzed reaction in isooctane at 40ºC and 0.73 water activity gave the best results, both in terms of the initial reaction rate and the enantioselectivity of the reaction. An increase in water activity allowed a higher reaction rate and enantiomeric excess in each of the four solvents. An increase in methyl branching did not necessarily increase the initial reaction rate, but it allowed a higher enantioselectivity, evidenced by an increase in the substrate enantiomeric excess.
Descritores: Alcanos
Ibuprofeno/farmacocinética
Ibuprofeno/farmacologia
-Candida/química
Lipase
Responsável: CL1.1 - Biblioteca Central


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Id: lil-497896
Autor: Potu, Bhagath Kumar; Rao, Muddanna S; Kutty N., Gopalan; Bhat, Kumar M. R; Chamallamudi, Mallikarjuna Rao; Nayak, Soubhagya Ranjan.
Título: Petroleum ether extract of Cissus quadrangularis (LINN) stimulates the growth of fetal bone during intra uterine developmental period: a morphometric analysis
Fonte: Clinics;63(6):815-820, 2008. ilus, graf.
Idioma: en.
Resumo: OBJECTIVE: The aim of the present study was to analyze the effect Cissus quadrangularis plant petroleum ether extract on the development of long bones during the intra-uterine developmental stage in rats. METHODS: Pregnant rats (n=12) were randomly assigned into either a control group (n=6) or a Cissus quadrangularis treatment (n=6) group. Pregnant rats in the Cissus quadrangularis group were treated with Cissus quadrangularis petroleum ether extract at a dose of 500 mg/kg body weight from gestation day 9 until delivery. The animals in the control group received an equal volume of saline. Newborn pups were collected from both groups for alizarin red S - alcian blue staining to differentiate ossified and unossified cartilage. The ossified cartilage (bone) was morphometrically analyzed using Scion image software. RESULTS: Morphometric analysis revealed that the percentage of the total length of ossified cartilage (bone) in pups born to treated dams was significantly higher (P<0.001- -0.0001) than that of the control group. CONCLUSION: The results of the present study suggest that maternal administration of Cissus quadrangularis petroleum ether extract during pregnancy can stimulate the development of fetal bone growth during the intra-uterine developmental period.
Descritores: Alcanos
Desenvolvimento Ósseo/efeitos dos fármacos
Cissus/química
Desenvolvimento Fetal/efeitos dos fármacos
Extratos Vegetais/farmacologia
-Distribuição Aleatória
Ratos Wistar
Testes de Toxicidade Aguda
Limites: Animais
Feminino
Gravidez
Ratos
Responsável: BR1.1 - BIREME


  9 / 11 LILACS  
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Id: lil-331802
Autor: Englebienne, P; López, M. G; Cortón, E; Viale, A. A.
Título: Use of a CO2 electrode to monitor fermentations that use xenobiotic compounds as source of carbon
Fonte: Rev. argent. microbiol;34(2):72-76, abr.-jun. 2002.
Idioma: en.
Resumo: Bacterial strains were isolated from contaminated waters, mud or soils. They are capable of growing in mineral medium with different chemicals as carbon source, such as aliphatic or aromatic hydrocarbons and polychlorinated biphenyls (PCBs). Most of these strains tolerate high concentrations (up to 30 v/v) of the xenobiotic substrates. This is particularly important for the development of fermenting processes to treat effluents or residues with a high content of contaminating compounds. An ion-specific potentiometric electrode (CO2) has been developed to measure CO2 production continuously. When the different strains were incubated in a mineral medium and in the presence of the corresponding substrate, a parallel between growth, substrate consumption and CO2 production was found. The developed system is suggested as an efficient and economical alternative to evaluate the potential of biodegradation by different microorganisms.
Descritores: Alcaligenes
Carbono
Dióxido de Carbono/análise
Eletrodos
Hidrocarbonetos
Micrococcus
Potenciometria
Pseudomonas aeruginosa
Xenobióticos/metabolismo
-Alcaligenes
Alcanos
Arocloros
Biodegradação Ambiental
Calibragem
Dióxido de Carbono/metabolismo
Poluentes Ambientais
Desenho de Equipamento
Fermentação
Micrococcus
Pseudomonas aeruginosa
Microbiologia do Solo
Estireno
Tolueno
Microbiologia da Água
Poluição Química da Água
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  10 / 11 LILACS  
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Id: lil-331142
Autor: Brown, Gerald O; Guardala, Noel A; Price, Jack L; Weiss, Richard G.
Título: Selectivity and efficiency of pyrene attachment to alkanes induced by broadband X-rays
Fonte: An. acad. bras. ciênc;75(1):33-38, Mar. 2003. graf.
Idioma: en.
Resumo: Bombardment of pyrene-doped n-heneicosane (C21H44) in its orthorhombic solid phase with <1.3> MeV broadband X-rays results in the formation of both mono- and di-heneicosylpyrenes, whereas the same dose in liquid cyclohexane yields only monosubstituted pyrene. In both cases, the reaction efficiency decreases as pyrene concentration is increased from 10-5 to 10-2 M. Qualitatively, the overall attachment efficiency is higher in orthorhombic n-heneicosane than in liquid cyclohexane, but the selectivity of attachment is greater in cyclohexane. Differences between these results and those from irradiations of the same samples with eV range photons are discussed
Descritores: Alcanos
Cicloexanos
Pirenos
-Alcanos
Cicloexanos
Pirenos
Responsável: BR1.1 - BIREME



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