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111.
Ramón Moreira Francisco Chenlo María D. Torres Beatriz Rama 《Food and Bioproducts Processing》2013,91(1):7-13
Chestnut flour doughs were prepared using chestnut air-dried at 45, 65, and 85 °C with constant load density (8.0 ± 0.6 kg/m2). Mixing curves of doughs using Mixolab® device showed that chestnut flour doughs dried at 85 °C needed more water absorption to reach the target consistency, (1.1 ± 0.07 Nm). Thermorheological properties were evaluated by means of a controlled stress rheometer. All tested doughs showed shear-thinning behaviour in the steady-shear tests (0.001–1 s?1). Oscillatory (1–100 rad s?1 at 0.1% strain), temperature sweep (30–90 °C) and creep-recovery (loading 50 Pa for 60 s) tests showed that flour doughs from chestnuts dried at 85 °C provide interesting properties, particularly remarkable elasticity that is associated with starch gelatinisation. Experimental data were described using various rheological models. 相似文献
112.
Cecilia Ramírez Adriana Saldaña Berenice Hernández Roberto Acero Ricardo Guerra Sergi Garcia-Segura Enric Brillas Juan M. Peralta-Hernández 《Journal of Industrial and Engineering Chemistry》2013,19(2):571-579
Solutions of methyl orange azo dye were degraded by electrochemical oxidation using a 3 L flow plant with a boron-doped diamond (BDD)/stainless steel cell operating at constant current density, ambient temperature and liquid flow rate of 12 L min?1. A 23 factorial design considering the applied current density, azo dye concentration and electrolysis time as variable independents was used to analyze the process by response surface methodology. LC–MS analysis revealed the formation of seven oxidation products from the cleavage of the NN group of the dye, followed by deamination, formation of a nitro group and/or desulfonation of the resulting aromatics. 相似文献
113.
Nanobelts are a new class of semiconducting metal oxide nanowires. The ribbon-like nanobelts are chemically pure and structurally uniform single crystals, with clean, sharp, smooth surfaces, and rectangular cross-sections. Positive and negative dielectrophoresis (DEP) was demonstrated for the first time on semiconducting oxide nanobelts. This effect was then used for the fabrication of a nanodevice, which consisted of SnO2 nanobelts attached to castellated gold electrodes defined on a glass substrate, and covered by a microchannel. The SnO2 nanobelts (width ∼ 100-300 nm, thickness ∼ 30-40 nm) were suspended in ethanol and introduced into the microchannel. An alternating (AC) voltage of ∼9.8 V peak to peak, with variable frequency, was applied between the electrodes (minimum electrode gap ∼ 20 μm), which corresponds to an average electric field strength of less than 2.5 × 105 V/m. In the 10 Hz-1 kHz range, repulsion between the nanobelts and the electrodes occurred, while in the 1-10 MHz range, attraction was observed. Once the nanobelts touched the electrodes, those that were sufficiently long bridged the electrode gaps. The device was characterized and can potentially be used as a nanosensor. 相似文献
114.
María Dolores López‐Ramírez Ulises Miguel García‐Ventura Fabricio Omar Barroso‐Muñoz Juan Gabriel Segovia‐Hernández Salvador Hernández 《化学工程与技术》2016,39(2):271-275
The esterification of oleic acid and methanol using sulfuric acid as a homogeneous catalyst is studied in reactive‐separation systems. The conversion of the free fatty acid was investigated in two different experiments with the molar ratio of methanol/oleic acid, amount of catalyst, temperature, and reaction time as variables. The conversion of the free fatty acid was found to depend strongly on the molar ratio of methanol/oleic acid. The reaction time had a direct effect on the conversion of the free fatty acid, and this conversion decreased with higher temperature. These results were valuable for a preliminary study on biodiesel production, using an acid homogeneous catalyst in a reactive dividing‐wall distillation column. 相似文献
115.
Boulaiz H Alvarez PJ Prados J Marchal J Melguizo C Carrillo E Peran M Rodríguez F Ramírez A Ortíz R Aránega A 《International journal of molecular sciences》2011,12(11):7445-7458
Breast cancer research has developed rapidly in the past few decades, leading to longer survival times for patients and opening up the possibility of developing curative treatments for advanced breast cancer. Our increasing knowledge of the biological pathways associated with the progression and development of breast cancer, alongside the failure of conventional treatments, has prompted us to explore gene therapy as an alternative therapeutic strategy. We previously reported that gef gene from E. coli has shown considerable cytotoxic effects in breast cancer cells. However, its action mechanism has not been elucidated. Indirect immunofluorescence technique using flow cytometry and immunocytochemical analysis were used to detect breast cancer markers: estrogen (ER) and progesterone (PR) hormonal receptors, human epidermal growth factor receptor-2 proto-oncogene (c-erbB-2), ki-67 antigen and p53 protein. gef gene induces an increase in ER and PR expressions and a decrease in ki-67 and c-erbB-2 gene expressions, indicating a better prognosis and response to treatment and a longer disease-free interval and survival. It also increased p53 expression, suggesting that gef-induced apoptosis is regulated by a p53-mediated signaling pathway. These findings support the hypothesis that the gef gene offers a new approach to gene therapy in breast cancer. 相似文献
116.
117.
Córdova MO Flores Ramírez CI Bejarano BV Arroyo Razo GA Pérez Flores FJ Tellez VC Ruvalcaba RM 《International journal of molecular sciences》2011,12(12):8575-8580
In this work, the results of a study comparing the use of irradiation from different regions of the infrared spectrum for the promotion of several organic reactions, are presented and discussed. This use of eco-conditions provides a green approach to chemical synthesis. A set of ten different organic reactions were evaluated, including the Knoevenagel, Hantzsch, Biginelli and Meldrum reactions. It is important to highlight the use of a commercial device that produces infrared irradiation in the near infrared region and its distribution by convection providing heating uniformity, significantly reducing reaction times, achieving good yields and proceeding in the absence of solvent. It is also worth noting that a variety of different reactions may be performed at the same time. Finally, the products obtained were identified using TLC, together with corresponding MS-data, complementarily in comparison of NMR (1)H and (13)C data with literature information. 相似文献
118.
Li and Tiwari (2008) recently developed a corrected Z-test statistic for comparing the trends in cancer age-adjusted mortality and incidence rates across overlapping geographic regions, by properly adjusting for the correlation between the slopes of the fitted simple linear regression equations. One of their key assumptions is that the error variances have unknown but common variance. However, since the age-adjusted rates are linear combinations of mortality or incidence counts, arising naturally from an underlying Poisson process, this constant variance assumption may be violated. This paper develops a weighted-least-squares based test that incorporates heteroscedastic error variances, and thus significantly extends the work of Li and Tiwari. The proposed test generally outperforms the aforementioned test through simulations and through application to the age-adjusted mortality data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. 相似文献
119.
Volpini R Marucci G Buccioni M Dal Ben D Lambertucci C Lammi C Mishra RC Thomas A Cristalli G 《ChemMedChem》2011,6(6):1074-1080
Guanosine, released extracellularly from neurons and glial cells, plays important roles in the central nervous system, including neuroprotection. The innovative DELFIA Eu‐GTP binding assay was optimized for characterization of the putative guanosine receptor binding site at rat brain membranes by using a series of novel and known guanosine derivatives. These nucleosides were prepared by modifying the purine and sugar moieties of guanosine at the 6‐ and 5′‐positions, respectively. Results of these experiments prove that guanosine, 6‐thioguanosine, and their derivatives activate a G protein‐coupled receptor that is different from the well‐characterized adenosine receptors. 相似文献
120.
Siva Ariyapadi Franco Berruti Ram Balachandar 《Chemical Engineering Communications》2003,190(12):1681-1704
The spray characteristics of a scaled-down version of an industrial feed nozzle are studied in the presence of a cross flow. Aerated liquid nitrogen is injected through the nozzle to generate the spray. The aeration rate is low and held constant, while two different liquid flow rates are used to produce the spray. A nonuniform wind profile is chosen to represent the cross flow condition. The droplet diameter and velocity measurements are acquired using a phase-Doppler particle analyzer. The results of the present study indicate that the spray momentum flux determines the extent of the jet bending. The droplets are accelerated significantly in the initial jet region as a result of flashing. However, further downstream of the nozzle, the vaporization of the droplets is considered to be negligible. The size-velocity correlation changes significantly for the case where the spray is shifted due to the cross flow. 相似文献