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In this work the synthesis, characterization, and gas transport properties of hydrogen selective silica membranes were studied along with the catalytic reforming of CH4 with CO2 (CH4 + CO z 2 CO + 2 H2) in a hydrogen separation membrane reactor. The silica membranes were prepared by chemical vapor deposition (CVD) of a thin SiO2 layer on porous supports (Vycor glass and alumina) using thermal decomposition of tetraethylorthosilicate (TEOS) in an inert atmosphere. These membranes displayed high hydrogen permeances (10-8 � 10-7 mol m-2 s-1 Pa-1) and excellent H2 selectivities (above 99.9 %) over other gases (CH4, CO, and CO2). The membranes were characterized using Scanning Electron Microscopy and Atomic Force Microscopy, and the mechanism of gas transport was studied applying existing theories with a newly developed treatment.

The catalytic reforming of CH4 with CO2 was carried out in a membrane reactor installed with a hydrogen separation ceramic membrane. The reaction was conducted at various pressures (1 � 20 atm) and temperatures (873 K and 923 K) at non-equilibrium conditions, and the results were compared with those obtained in a packed bed reactor in order to evaluate performance of the membrane reactor for the reaction. It was found that concurrent and selective removal of hydrogen from the reaction in the membrane reactor resulted in considerable enhancements in the yields of the reaction products, H2 and CO. The enhancements in the product yields in the membrane reactor increased with pressure showing a maximum at 5 atm, and then decreased at higher pressures. This was due to a trade-off between a thermodynamic quantity (hydrogen production by the reaction) and transport property (hydrogen separation through the membrane). It was also found that the reverse water-gas shift (RWGS) reaction occurred simultaneously with the reforming reaction giving the detrimental effect on the reaction system by reducing the amount of hydrogen production in favor of water. This was particularly significant at high pressures.

In this work the synthesis, characterization, and gas transport properties of hydrogen selective silica membranes were studied along with the catalytic reforming of CH4 with CO2 (CH4 + CO z 2 CO + 2 H2) in a hydrogen separation membrane reactor. The silica membranes were prepared by chemical vapor deposition (CVD) of a thin SiO2 layer on porous supports (Vycor glass and alumina) using thermal decomposition of tetraethylorthosilicate (TEOS) in an inert atmosphere. These membranes displayed high hydrogen permeances (10-8 � 10-7 mol m-2 s-1 Pa-1) and excellent H2 selectivities (above 99.9 %) over other gases (CH4, CO, and CO2). The membranes were characterized using Scanning Electron Microscopy and Atomic Force Microscopy, and the mechanism of gas transport was studied applying existing theories with a newly developed treatment.

The catalytic reforming of CH4 with CO2 was carried out in a membrane reactor installed with a hydrogen separation ceramic membrane. The reaction was conducted at various pressures (1 � 20 atm) and temperatures (873 K and 923 K) at non-equilibrium conditions, and the results were compared with those obtained in a packed bed reactor in order to evaluate performance of the membrane reactor for the reaction. It was found that concurrent and selective removal of hydrogen from the reaction in the membrane reactor resulted in considerable enhancements in the yields of the reaction products, H2 and CO. The enhancements in the product yields in the membrane reactor increased with pressure showing a maximum at 5 atm, and then decreased at higher pressures. This was due to a trade-off between a thermodynamic quantity (hydrogen production by the reaction) and transport property (hydrogen separation through the membrane). It was also found that the reverse water-gas shift (RWGS) reaction occurred simultaneously with the reforming reaction giving the detrimental effect on the reaction system by reducing the amount of hydrogen production in favor of water. This was particularly significant at high pressures.

A team of researchers led by Consejo Superior de Investigaciones Científicas (CSIC) Juan José Calvete has characterized the protein composition of the venom of the rattlesnake Crotalus atrox U.S., which together with Crotalus adamanteus, is responsible for Most poisoning accidents in the U.S.. The research is part of a larger project that seeks to understand the molecular basis of the evolution of venoms of the genus, widely distributed throughout the American continent. The study will improve the production and effectiveness of antidotes that neutralize the toxicity of the venom of these snakes. The work is published in the Journal of Proteome Research.

Calvete detailed research: "We identified by proteomic techniques which families of toxins are present in the venom of this snake, and also had given his relative concentration. This information is relevant to know what arsenal against biological antidotes should be prepared" .

A team of researchers led by Consejo Superior de Investigaciones Científicas (CSIC) Juan José Calvete has characterized the protein composition of the venom of the rattlesnake Crotalus atrox U.S., which together with Crotalus adamanteus, is responsible for Most poisoning accidents in the U.S.. The research is part of a larger project that seeks to understand the molecular basis of the evolution of venoms of the genus, widely distributed throughout the American continent. The study will improve the production and effectiveness of antidotes that neutralize the toxicity of the venom of these snakes. The work is published in the Journal of Proteome Research.

Calvete detailed research: "We identified by proteomic techniques which families of toxins are present in the venom of this snake, and also had given his relative concentration. This information is relevant to know what arsenal against biological antidotes should be prepared" .

Purpose of wastewater treatment:
- Achieve obtaining drinking water that is chemically and bacteriologically safe. It may be used for human consumption or have the quality needed for industrial processes. "For domestic uses, water treatment needs to ensure the exemption of tastes and odors. Furthermore, water should be improved with agents that may contribute to health, such as fluorine. - Main purposes: to reduce the BOD content, achieving the reduction of suspended solids, reduce or completely eliminate all pathogens.

Selecting the process for water treatment:
For example, in lakes and reservoirs, causing algae bloom problems of tastes and smells, but rude to the leak. This can be controlled using chemicals like copper sulfate.

Purpose of wastewater treatment:
- Achieve obtaining drinking water that is chemically and bacteriologically safe. It may be used for human consumption or have the quality needed for industrial processes. "For domestic uses, water treatment needs to ensure the exemption of tastes and odors. Furthermore, water should be improved with agents that may contribute to health, such as fluorine. - Main purposes: to reduce the BOD content, achieving the reduction of suspended solids, reduce or completely eliminate all pathogens.

Selecting the process for water treatment:
For example, in lakes and reservoirs, causing algae bloom problems of tastes and smells, but rude to the leak. This can be controlled using chemicals like copper sulfate.