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261.
SRB measures for partially hyperbolic systems whose central direction is mostly expanding 总被引:4,自引:0,他引:4
We construct Sinai-Ruelle-Bowen (SRB) measures supported on partially hyperbolic sets of diffeomorphisms – the tangent bundle
splits into two invariant subbundles, one of which is uniformly contracting – under the assumption that the complementary
subbundle is non-uniformly expanding. If the rate of expansion (Lyapunov exponents) is bounded away from zero, then there are only finitely many SRB
measures. Our techniques extend to other situations, including certain maps with singularities or critical points, as well
as diffeomorphisms having only a dominated splitting (and no uniformly hyperbolic subbundle).
Oblatum 16-IV-1999 & 29-X-1999?Published online: 21 February 2000 相似文献
262.
Estelle Rascol Sandrine Villette Etienne Hart Isabel D. Alves 《Molecules (Basel, Switzerland)》2021,26(21)
Plasmon waveguide resonance (PWR) is a variant of surface plasmon resonance (SPR) that was invented about two decades ago at the University of Arizona. In addition to the characterization of the kinetics and affinity of molecular interactions, PWR possesses several advantages relative to SPR, namely, the ability to monitor both mass and structural changes. PWR allows anisotropy information to be obtained and is ideal for the investigation of molecular interactions occurring in anisotropic-oriented thin films. In this review, we will revisit main PWR applications, aiming at characterizing molecular interactions occurring (1) at lipid membranes deposited in the sensor and (2) in chemically modified sensors. Among the most widely used applications is the investigation of G-protein coupled receptor (GPCR) ligand activation and the study of the lipid environment’s impact on this process. Pioneering PWR studies on GPCRs were carried out thanks to the strong and effective collaboration between two laboratories in the University of Arizona leaded by Dr. Gordon Tollin and Dr. Victor J. Hruby. This review provides an overview of the main applications of PWR and provides a historical perspective on the development of instruments since the first prototype and continuous technological improvements to ongoing and future developments, aiming at broadening the information obtained and expanding the application portfolio. 相似文献
263.
Dr. Gabriel P. Da Costa Gustavo B. Blödorn Prof. Dr. Thiago Barcellos Prof. Dr. Márcio S. Silva Prof. Dr. Rafael Luque Prof. Dr. Diego Alves 《European journal of organic chemistry》2023,26(30):e202300604
We described here a simple and metal-free protocol to synthesize [1,2,3]triazolo[1,5-a]quinoline 3-carboxamides through a two-step synthetic strategy, in which the first step uses organocatalysis (10 mol % of diethylamine or 1,8-diazabicyclo[5.4.0]undec-7-ene, while the second step involves the use of inorganic base (1.2 or 0.1 equiv. of potassium hydroxide). These reactions were performed between β-keto amides and o-carbonyl phenylazides in dimethylsulfoxide as solvent at 70 °C for 2 h. The synthetic protocol is ample, which thirteen examples of secondary [1,2,3]triazolo[1,5-a]quinoline 3-carboxamides were synthesized ranging from good to excellent yields (63-96 %), and six different tertiary [1,2,3]triazolo[1,5-a]quinolines 3-carboxamides were obtained ranging from moderate to good yields (48–76 %). 相似文献
264.
da Silva Bruno Fonseca da Silva Karolayne Esthefany Melo de Farias Emerson Emiliano Gualberto de França Elvis Joacir Martins Mônica Cristina Barroso de Oliveira Santos Mariana Luiza de Lourdes Lacerda Buril Maria da Silva Alves Gustavo Gabriel de Oliveira Silva Andrezza Karla de Lira Júnior Ednaldo Barbalho da Silva Nicácio Herique Pereira Eugênia C. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3671-3679
Journal of Radioanalytical and Nuclear Chemistry - This study aimed to evaluate the effects of the Rn-222 progeny on the lichen Cladonia verticillaris under controlled conditions. The results... 相似文献
265.
de Melo Anely Maciel Barbi Rafaela Cristina Turola Costa Bruno Patrício Ikeda Mônica Alves Fillemon Edillyn Silva Bambirra Carpiné Danielle Ribani Rosemary Hoffmann 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12313-12328
Journal of Thermal Analysis and Calorimetry - Despite their being rich in bioactive compounds, by-products produced during fruit pulping are usually discarded. The present paper aimed to... 相似文献
266.
Alves L Salgueiro R Rodrigues C Mesquita E Matos J Gírio FM 《Applied biochemistry and biotechnology》2005,120(3):199-208
A novel bacterium, Gordonia alkanivorans strain 1B, was isolated from hydrocarbon-contaminated soil. Assessment of the biodegradation of distinct organic sulfur-compounds,
such as dibenzothiophene (DBT), benzothiophene (BT), DBT sulfone, and alkylated tiophenic compounds, as the sole source of
sulfure was investigated. G. alkanivorans strain 1B was able to remove selectively the sulfur from DBT while keeping intact the remaining carbon-carbon structure.
Orthophenyl phenol (2-hydroxybiphenyl) was the only detected metabolic product. The bacterial desulfurization activity was
repressed by sulfate. G. alkanivorans straini 1B consumed 310 μM DBT after 120 h of cultivation, corresponding to a specific desulfurization rate of 1.03 μmol/(g of dry cells·h). When an
equimolar mixture of DBT/BT was used as a source of sulfur in the growth medium, G. alkanivorans strain 1B assimilated both compounds in a sequential manner, with BT as the preferred source of sulfur. Only when BT concentration
was decreased to a very low level was DBT utilized as the source of sulfur for bacterial growth. Thespecific desulfurization
overall rates of BT and DBT obtained were 0.954 and 0.813 μmol/(g of dry cells·h), respectively. The newly isolated G. alkanivorans strain 1B has good potential for application in the biodesulfurization of fossil fuels. 相似文献
267.
Biphentrin, a known pyrethroid, was studied, aiming its removal from aqueous solutions by granulated cork sorption. Batch experiments, either for equilibrium or for kinetics, with two granulated cork sizes were performed and results were compared with those obtained with of activated carbon sorption. Langmuir and Freundlich adsorption isotherms were obtained both showing high linear correlations. Bifenthrin desorption was evaluated for cork and results varied with the granule size of sorbent. The results obtained in this work indicate that cork wastes may be used as a cheap natural sorbent for bifenthrin or similar compounds removal from wastewaters. 相似文献
268.
In this work, Amberlite XAD-2 resin functionalized with 4,5-dihydroxy-1,3-benzenedisulfonic acid was synthesized, characterized and applied as a new packing material for an on-line system to nickel preconcentration. The method is based on the sorption of Ni(II) ions in a minicolumn containing the synthesized resin, posterior desorption using an acid solution and measurement of the nickel by spectrophotometry (PAR method). The optimization of the system was performed using factorial design and Doehlert matrix considering five variables: eluent concentration, PAR solution pH, sample flow rate, PAR solution concentration and sample pH. Signals were measured as peak height by using an instrument software. Using the experimental conditions defined in the optimization, the method allowed nickel determination with achieved sampling rate of 25 samples per hour, detection limit (3 s) of 2 μg l−1 and precision (assessed as the relative standard deviation) of 8.2-2.6%, for nickel solutions of 10.0-200.0 μg l−1 concentration, respectively. The experimental enrichment factor of the proposed system was 46, for 120 s preconcentration time. The proposed procedure was applied for nickel determination in food samples. Recoveries of spike additions (5 or 10 μg g−1) to food samples were quantitative (94-110%). 相似文献
269.
Graziela Teixeira de Oliveira Jaqueline Maria Siqueira Ferreira William Gustavo Lima Lucas Ferreira Alves Joaquim Maurício Duarte-Almeida 《Natural product research》2018,32(6):723-731
Ethanol extract and fractions obtained from fresh and dry aerial parts of Lippia alba were examined in order to determine their phytochemical composition, antioxidant capacity and antibacterial activities. The ethanol extracts and fractions exhibited an antioxidant effect by the DPPH assay, especially samples of fresh plant. HPLC analysis of the ethyl acetate fractions identified the presence of phenolic acids and flavonoids. The ethanol extract and fractions showed activity against reference and multidrug-resistant strains of Staphylococcus aureus and Enterococcus faecalis (MIC range 2000–250 μg/mL). The hexane and dichloromethane fractions of fresh plant showed better activity against reference strains of Escherichia coli (MIC of 250 and 125 μg/mL, respectively), but all extracts and fractions were less active against multidrug-resistant strains of all the Gram-negative species evaluated. The results showed that the extract and fractions of L alba aerial parts showed antibacterial activity, even against multidrug-resistant Gram-positive bacteria, and antioxidant effect (DPPH assay). 相似文献
270.
Dobies Návia Marcos Vinícius Alves Gálico Diogo Junior Caires Flávio Marques Luiz José Spezia Nunes Ronaldo 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1717-1727
Journal of Thermal Analysis and Calorimetry - Solid-state [Ln(nal)3]·nH2O compounds, where Ln represents light trivalent lanthanide (La to Sm, except Pm), nal is nalidixate (C12H11N2O3), and n... 相似文献