Limiting withdrawal rate and maximum film thickness during dip-coating of titania sols onto a Si substrate

The article highlights new insights into production of thin titania films widely used as catalyst support in many modern reactors including capillary microreactors, microstructured fixed-bed reactors and falling film microreactors. Dip-coating of a Mania sol onto a Si substrate has been studied in the range of the sol viscosities of 1.5-2.5 mPa s and the sol withdrawal rates of 0.2-18 mm/s. Different viscosities of sols were created by addition of desired amounts of nitric acid to the synthesis mixture of titanium isopropoxide and Plutonic F127 in ethanol which allowed to control the rate of the condensation reactions. Uniform inesoporous titania coatings were obtained at the solvent withdrawal rates below 10 mm/s at sol viscosities in the range from 1.6 mPa s to 2.5 mPa s. There exists a limiting withdrawal rate corresponding to a capillary number of ca. 0.01 beyond which uniform titania films cannot be obtained. Below the limiting withdrawal rate, the coating thickness is a power function of the sol viscosity and withdrawal rate, both with an exponent of 2/3. The limiting withdrawal rate increases as the solvent evaporation rate increases and it decreases as the sol viscosity increases. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.

T- and L-type Ca2+ currents in freshly dispersed smooth muscle cells from the human proximal urethra

The purpose of the present study was to characterise Ca2+ currents in smooth muscle cells isolated from biopsy samples taken from the proximal urethra of patients undergoing surgery for bladder or prostate cancer. Cells were studied at 37 degreesC using the amphotericin B perforated-patch configuration of the patch-clamp technique. Currents were recorded using Cs+-rich pipette solutions to block K+ currents. Two components of current, with electrophysiological and pharmacological properties typical of T- and L-type Ca2+ currents, were present in these cells. When steady-state inactivation curves for the L current were fitted with a Boltzmann equation, this yielded a V-1/2 of -45 +/- 5 mV. In contrast, the T current inactivated with a V-1/2 of -80 +/- 3 mV. The L currents were reduced in a concentration-dependent manner by nifedipine (ED50 = 159 +/- 54 nm) and Ni2+ (ED50 = 65 +/- 16 muM) but were enhanced when external Ca2+ was substituted with Ba2+. The T current was little affected by TTX, reduction in external Na+, application of nifedipine at concentrations below 300 nm or substitution of external Ca2+ with Ba2+, but was reduced by Ni2+ with an ED50 of 6 +/- 1 mum. When cells were stepped from -100 to -30 mV in Ca2+-free conditions, small inward currents could be detected. These were enhanced 40-fold in divalent-cation-free solution and blocked in a concentration-dependent manner by Mg2+ with an ED50 of 32 +/- 16 mum. These data support the idea that human urethral myocytes possess currents with electrophysiological and pharmacological properties typical of T- and L-type Ca2+ currents.

Hydroprocessing of waste cooking oil over a dispersed nano catalyst: Kinetics study and temperature effect

The kinetics of hydrodeoxygenation of waste cooking oil (WCO) is investigated with unsupported CoMoS catalysts. A kinetic model is established and a comprehensive analysis of each reaction pathway is carried out. The results show that hydrodecarbonylation/decarboxylation (HDC) routes are the predominant reaction pathways in the elimination of oxygen, with the rate constant three times as high as that of hydrodeoxygenation (HDO). However, the HDC activity of the CoMoS catalyst deactivates due to gradual loss of sulfur from the catalyst. HDO process is insensitive to the sulfur deficiency. The kinetic modeling shows that direct hydrodecarbonylation of fatty acids dominates the HDC routes and, in the HDO route, fatty acids are transferred to aldehydes/alcohols and then to C-18 hydrocarbons, a final product, and the reduction of acids is the rate limiting step. The HDO route via alcohols is dominant over aldehydes due to a significantly higher reaction rate constant. The difference of C-18/C-17 ratio in unsupported and supported catalysts show that a support with Lewis acid sites may play an important role in the selectivity for the hydrodeoxygenation pathways and promoting the final product quality

Selective hydrogenation of fatty acids to alcohols over highly dispersed ReOx/TiO2 catalyst

Production of fatty alcohols through selective hydrogenation of fatty acids was studied over a 4% ReOx/TiO2 catalyst. Stearic acid was hydrogenated to octadecanol at temperatures and pressures between 180-200 degrees C and 2-4 MPa, with selectivity reaching 93%. A high yield of octadecanol was attributed to a strong adsorption of the acid compared to alcohol on the catalyst, which inhibits further alcohol transformation to alkanes. Low amounts (<7%) of alkanes (mainly octadecane) were formed during the conversion of stearic acid. However, it was found that the catalyst could be tuned for the production of alkanes. The reaction intermediates were octadecanal and stearyl stearate. Based on the reaction products analysis and catalyst characterization, a reaction mechanism and possible pathways were proposed.

From dispersed to monopolized violence: expansion and consolidation of the Primeiro Comando da Capital's hegemony in São Paulo's prisons

The present work aims to understand the process of expansion and consolidation of the organized criminal group the Primeiro Comando da Capital (PCC) in São Paulo’s prison system over the past 20 years, and the social configuration that has formed as a result of the PCCs monopolization of opportunities of power. To this end, the work of Norbert Elias is utilized to analyze empirical data collected from various sources. The article consists of two lines of analysis. First, the PCC phenomenon is approached from a macro-sociological point of view, focusing on the social, political and administrative problems that are directly or indirectly linked to the PCCs social development. Second, a figurational analysis is used to explore the social dynamics produced from this process. In comparison to the “pre-PCC” situation, it is shown that the new social configuration produced from the hegemony of the PCC consists of a complexity of interdependencies, including greater functional division and social integration. Given this intensification of mutual dependencies, the social controls on individual behavior have been expanded and centralized. Here, the structure and organization of the PCC, its political dynamics, and individual self-control are central issues. The article concludes by calling into question the view that the most significant effect of the PCCs consolidation has been social pacification of São Paulo’s prison system. Fragilities in the power of the PCC are explored, principally the precarious nature of the relationship between the PCC and state authorities, and the extent to which the PCC’s authority is imposed.

Integrating Social Knowledge and Collaboration Tools into Dispersed Product Development

Employee collaboration and knowledge sharing is vital for manufacturing organisations wishing to be successful in an ever-changing global market place; Product Development (PD) teams, in particular, rely heavily on these activities to generate innovative designs and enhancements to existing product ranges. To this end, the purpose of this paper is to present the results of a validation study carried out during an Engineering Education Scheme project to confirm the benefits of using bespoke Web 2.0-based groupware to improve employee collaboration and knowledge sharing between dispersed PD teams. The results of a cross-sectional survey concluded that employees would welcome greater usage of social computing technologies. The study confirmed that groupware offers the potential to deliver a more effective collaborative and knowledge sharing environment with additional communication channels on offer. Furthermore, a series of recommended guidelines are presented to show how PD teams, operating in globally dispersed organisations, may use Web 2.0 tools to improve employee collaboration and knowledge sharing.

Arrêt du Conseil d'Etat qui ordonne qu'en payant par le sieur Prévost de Serainville la somme de 6.000 l. et les 2 sols pour livre pour l'acquisition d'un office de secrétaire du Roi, il sera déchargé de toutes taxes pour la recherche de la noblesse

[Acte. 1714-01-16. Versailles]

Arrêt du conseil d'état qui ordonne que ceux des officiers des chancelleries près les cours et conseils supérieurs du royaume, qui payeront leur supplément de finance dans les termes y indiqués, seront déchargés des 2 sols pour livre

[Acte. 1755-11-25. Versailles]

Arrêt du conseil d'état qui ordonne que les quittances de finance pour l'acquisition des 1800000 livres de rentes héréditaires au denier vingt, créées sur l'imposition des deux sols pour livres en sus du dixième, seront expédiées au choix des acquéreurs en leur nom ou au porteur

[Acte. 1756-08-31. Versailles]

Recuperación de materiales de lata aleación por soldadura Juan Oscar Molina Solís

Tesis (Maestría en Ciencias de la Ingeniería Mecánica con especialidad en Materiales) U.A.N.L.

¿Es el gen humano hPL-1 un pseudogen? análisis de su expresión in vivo usando técnicas de ingeniería genética y cultivo celular por Ramiro Ramírez Solís

Tesis (Maestría en Ciencias) U.A.N.L.