Pedro Alvarez - Academia.edu (original) (raw)
Papers by Pedro Alvarez
Didactica De Las Ciencias Y Transversalidad 1998 Isbn 84 600 9487 1 Pags 47 54, 1998
Información del artículo Valoración de problemas ambientales en profesores de primaria y ESO: imp... more Información del artículo Valoración de problemas ambientales en profesores de primaria y ESO: implicaciones para la educación ambiental.
Proceedings of the 7th International Conference on E Commerce and Web Technologies, 2006
The core functionality of Web-service middlewares tries to wrap existing business logics and make... more The core functionality of Web-service middlewares tries to wrap existing business logics and make them accessible as Web services. Recently, well-known standardization initiatives have proposed some high-level declarative languages for the description of coordination protocols and the implementation of coordination middlewares. In parallel to these initiatives, an increasing interest on the use of classical coordination models on distributed environments has
Wad Al Hayara Revista De Estudios De Guadalajara, 1987
J Air Waste Manage Assoc, 2008
The AP-42 method has been recommended by the U.S. Environment Protection Agency to collect dust e... more The AP-42 method has been recommended by the U.S. Environment Protection Agency to collect dust emission data. According to this method, the number of sampling sites needs to be determined first. At these sites, the dust will be collected based on plots drawn on the road surface. Apparently, there has been no systematic rule to follow to determine the number of sampling sites. In addition, it is not known whether the required number of plots and their sizes are validated based on real data. Mobile sampling technology can collect dust emission data at very close space intervals, which to some extent can be viewed as being close to actual dust emission data continuously distributed over roadway segments. With such data available, this study investigated the number of sampling sites and the number of plots and their sizes based on the optimal allocation sampling method and the Monte Carlo simulation method. The results from the optimal allocation method indicated that most of the sampling sites should be drawn from the local roads because the variance of emission and proportion of road segments of this roadway classification are significantly bigger than other roadway classifications. This observation may lead to the application of other cost-effective sampling approaches. The results from the Monte Carlo simulation method imply that clear patterns of improved estimation of emission factors versus plot number and size can be observed only for three roadway classifications, not for other classifications. This result indicates that the AP-42 method may not be applicable to some roadway classifications, and thus different data collection methods such as the mobile sampling technology may be necessary.
Http Dx Doi Org 10 1080 01919510490455692, Aug 10, 2010
ABSTRACT This article presents a laboratory study of the ozonation of diluted cherry stillage, a ... more ABSTRACT This article presents a laboratory study of the ozonation of diluted cherry stillage, a high-strength wastewater. Influence of variables, kinetics, and the effects of an ozonation stage coupled with the biological treatment by activated sludge are addressed. ...
Ozone Science and Engineering, May 21, 2007
Film theory has been applied to model the ozonation kinetics of a domestic wastewater. The model ... more Film theory has been applied to model the ozonation kinetics of a domestic wastewater. The model has been applied to the ozonation in a bubble column where gas and wastewater were fed countercurrently. Because the wastewater composition was not explicitly known, an index of its pollution (i.e., COD) has been taken as the parameter to study the chemical reaction kinetics.
Biodegradation, Mar 1, 2010
Utopia Y Praxis Latinoamericana Revista Internacional De Filosofia Iberoamericana Y Teoria Social, 2009
Ozone Science Engineering, Nov 29, 2010
... & Eng., 17:163-181 (1995) FJ BELTRAN; JF GARCÍA-ARAYA; P. ÁLVAREZ, "Impact of chemic... more ... & Eng., 17:163-181 (1995) FJ BELTRAN; JF GARCÍA-ARAYA; P. ÁLVAREZ, "Impact of chemical oxidation on biological treatment of a primary municipal wastewater. 2. Effects of ozonation on kinetics of biological oxidation", Ozone: Sci. ...
Water Sci Technol, 2008
Stable fullerene water suspensions (nC(60)) exhibited potent antibacterial activity to physiologi... more Stable fullerene water suspensions (nC(60)) exhibited potent antibacterial activity to physiologically different bacteria in low-salts media over a wide range of exposure conditions. Antibacterial activity was observed in the presence or absence of light or oxygen, and increased with both exposure time and dose. The activity was also influenced by the nC(60) storage conditions and by the age of the buckminsterfullerene (C(60)) used to make nC(60). These results reflect the potential impact of nC(60) on the health of aquatic ecosystems and suggest novel alternatives for disinfection and microbial control.
Drying Technology, Jul 1, 2005
... Please use this identifier to cite or link to this item: http://hdl.handle.net/10533/20847\. T... more ... Please use this identifier to cite or link to this item: http://hdl.handle.net/10533/20847. Title: COCURRENT DOWNFLOW FLUIDIZED BED DRYER: EXPERIMENTAL EQUIPMENT AND MODELING. Authors: PEDRO IVAN ALVAREZ GUTIERREZ. Keywords: AI-1020384. ...
Environ Toxicol Chem, 1996
Abstract The UV photolysis and H 2 O 2/UV advanced oxidation of two intermediate compounds of the... more Abstract The UV photolysis and H 2 O 2/UV advanced oxidation of two intermediate compounds of the degradation of atrazine in water, deethylatrazine and deisopropylatrazine, have been studied. The influence of hydrogen peroxide and bicarbonate ion ...
Environmental Toxicology and Chemistry, 2003
Biodegradation, Dec 1, 2005
Substrates and nutrients are often added to contaminated soil or groundwater to enhance bioremedi... more Substrates and nutrients are often added to contaminated soil or groundwater to enhance bioremediation. Nevertheless, this practice may be counterproductive in some cases where nutrient addition might relieve selective pressure for pollutant biodegradation. Batch experiments with a homoacetogenic pure culture of Acetobacterium paludosum showed that anaerobic RDX degradation is the fastest when auxiliary growth substrates (yeast extract plus fructose) and nitrogen sources (ammonium) are not added. This bacterium degraded RDX faster under autotrophic (H2-fed) than under heterotrophic conditions, even though heterotrophic growth was faster. The inhibitory effect of ammonium is postulated to be due to the repression of enzymes that initiate RDX degradation by reducing its nitro groups, based on the known fact that ammonia represses nitrate and nitrite reductases. This observation suggests that the absence of easily assimilated nitrogen sources, such as ammonium, enhances RDX degradation. Although specific end products of RDX degradation were not determined, the production of nitrous oxide (N2O) suggests that A. paludosum cleaved the triazine ring.
Environ Sci Technol, 2006
Fullerene research in biological systems has been hindered by the compound&am... more Fullerene research in biological systems has been hindered by the compound's relative insolubility in water. However, C60 molecules can be made to aggregate, forming stable fullerene water suspensions (FWS) whose properties differ from those of bulk solid C60. There are many different protocols for making FWS. This paper explores four of these methods and establishes the antibacterial activity of each resulting suspension, including a suspension made without intermediary solvents. The aggregates in each polydisperse suspension were separated by size using differential centrifugation and tested for antibacterial activity using Bacillus subtilis as a test organism. All suspensions exhibited relatively strong antibacterial activity. Fractions containing smaller aggregates had greater antibacterial activity, although the increase in toxicity was disproportionately higher than the associated increase in putative surface area. This suggests the need for improved understanding of the behavior of FWS towards organisms and in the environment to determine how C60 can be safely used and disposed.
Nano Letters, May 1, 2008
Fullerene research in biological systems has been hindered by the compound&am... more Fullerene research in biological systems has been hindered by the compound's relative insolubility in water. However, C60 molecules can be made to aggregate, forming stable fullerene water suspensions (FWS) whose properties differ from those of bulk solid C60. There are many different protocols for making FWS. This paper explores four of these methods and establishes the antibacterial activity of each resulting suspension, including a suspension made without intermediary solvents. The aggregates in each polydisperse suspension were separated by size using differential centrifugation and tested for antibacterial activity using Bacillus subtilis as a test organism. All suspensions exhibited relatively strong antibacterial activity. Fractions containing smaller aggregates had greater antibacterial activity, although the increase in toxicity was disproportionately higher than the associated increase in putative surface area. This suggests the need for improved understanding of the behavior of FWS towards organisms and in the environment to determine how C60 can be safely used and disposed.
Atlantica Xxii Revista Asturiana De Informacion Y Pensamiento, 2010
Didactica De Las Ciencias Y Transversalidad 1998 Isbn 84 600 9487 1 Pags 47 54, 1998
Información del artículo Valoración de problemas ambientales en profesores de primaria y ESO: imp... more Información del artículo Valoración de problemas ambientales en profesores de primaria y ESO: implicaciones para la educación ambiental.
Proceedings of the 7th International Conference on E Commerce and Web Technologies, 2006
The core functionality of Web-service middlewares tries to wrap existing business logics and make... more The core functionality of Web-service middlewares tries to wrap existing business logics and make them accessible as Web services. Recently, well-known standardization initiatives have proposed some high-level declarative languages for the description of coordination protocols and the implementation of coordination middlewares. In parallel to these initiatives, an increasing interest on the use of classical coordination models on distributed environments has
Wad Al Hayara Revista De Estudios De Guadalajara, 1987
J Air Waste Manage Assoc, 2008
The AP-42 method has been recommended by the U.S. Environment Protection Agency to collect dust e... more The AP-42 method has been recommended by the U.S. Environment Protection Agency to collect dust emission data. According to this method, the number of sampling sites needs to be determined first. At these sites, the dust will be collected based on plots drawn on the road surface. Apparently, there has been no systematic rule to follow to determine the number of sampling sites. In addition, it is not known whether the required number of plots and their sizes are validated based on real data. Mobile sampling technology can collect dust emission data at very close space intervals, which to some extent can be viewed as being close to actual dust emission data continuously distributed over roadway segments. With such data available, this study investigated the number of sampling sites and the number of plots and their sizes based on the optimal allocation sampling method and the Monte Carlo simulation method. The results from the optimal allocation method indicated that most of the sampling sites should be drawn from the local roads because the variance of emission and proportion of road segments of this roadway classification are significantly bigger than other roadway classifications. This observation may lead to the application of other cost-effective sampling approaches. The results from the Monte Carlo simulation method imply that clear patterns of improved estimation of emission factors versus plot number and size can be observed only for three roadway classifications, not for other classifications. This result indicates that the AP-42 method may not be applicable to some roadway classifications, and thus different data collection methods such as the mobile sampling technology may be necessary.
Http Dx Doi Org 10 1080 01919510490455692, Aug 10, 2010
ABSTRACT This article presents a laboratory study of the ozonation of diluted cherry stillage, a ... more ABSTRACT This article presents a laboratory study of the ozonation of diluted cherry stillage, a high-strength wastewater. Influence of variables, kinetics, and the effects of an ozonation stage coupled with the biological treatment by activated sludge are addressed. ...
Ozone Science and Engineering, May 21, 2007
Film theory has been applied to model the ozonation kinetics of a domestic wastewater. The model ... more Film theory has been applied to model the ozonation kinetics of a domestic wastewater. The model has been applied to the ozonation in a bubble column where gas and wastewater were fed countercurrently. Because the wastewater composition was not explicitly known, an index of its pollution (i.e., COD) has been taken as the parameter to study the chemical reaction kinetics.
Biodegradation, Mar 1, 2010
Utopia Y Praxis Latinoamericana Revista Internacional De Filosofia Iberoamericana Y Teoria Social, 2009
Ozone Science Engineering, Nov 29, 2010
... & Eng., 17:163-181 (1995) FJ BELTRAN; JF GARCÍA-ARAYA; P. ÁLVAREZ, "Impact of chemic... more ... & Eng., 17:163-181 (1995) FJ BELTRAN; JF GARCÍA-ARAYA; P. ÁLVAREZ, "Impact of chemical oxidation on biological treatment of a primary municipal wastewater. 2. Effects of ozonation on kinetics of biological oxidation", Ozone: Sci. ...
Water Sci Technol, 2008
Stable fullerene water suspensions (nC(60)) exhibited potent antibacterial activity to physiologi... more Stable fullerene water suspensions (nC(60)) exhibited potent antibacterial activity to physiologically different bacteria in low-salts media over a wide range of exposure conditions. Antibacterial activity was observed in the presence or absence of light or oxygen, and increased with both exposure time and dose. The activity was also influenced by the nC(60) storage conditions and by the age of the buckminsterfullerene (C(60)) used to make nC(60). These results reflect the potential impact of nC(60) on the health of aquatic ecosystems and suggest novel alternatives for disinfection and microbial control.
Drying Technology, Jul 1, 2005
... Please use this identifier to cite or link to this item: http://hdl.handle.net/10533/20847\. T... more ... Please use this identifier to cite or link to this item: http://hdl.handle.net/10533/20847. Title: COCURRENT DOWNFLOW FLUIDIZED BED DRYER: EXPERIMENTAL EQUIPMENT AND MODELING. Authors: PEDRO IVAN ALVAREZ GUTIERREZ. Keywords: AI-1020384. ...
Environ Toxicol Chem, 1996
Abstract The UV photolysis and H 2 O 2/UV advanced oxidation of two intermediate compounds of the... more Abstract The UV photolysis and H 2 O 2/UV advanced oxidation of two intermediate compounds of the degradation of atrazine in water, deethylatrazine and deisopropylatrazine, have been studied. The influence of hydrogen peroxide and bicarbonate ion ...
Environmental Toxicology and Chemistry, 2003
Biodegradation, Dec 1, 2005
Substrates and nutrients are often added to contaminated soil or groundwater to enhance bioremedi... more Substrates and nutrients are often added to contaminated soil or groundwater to enhance bioremediation. Nevertheless, this practice may be counterproductive in some cases where nutrient addition might relieve selective pressure for pollutant biodegradation. Batch experiments with a homoacetogenic pure culture of Acetobacterium paludosum showed that anaerobic RDX degradation is the fastest when auxiliary growth substrates (yeast extract plus fructose) and nitrogen sources (ammonium) are not added. This bacterium degraded RDX faster under autotrophic (H2-fed) than under heterotrophic conditions, even though heterotrophic growth was faster. The inhibitory effect of ammonium is postulated to be due to the repression of enzymes that initiate RDX degradation by reducing its nitro groups, based on the known fact that ammonia represses nitrate and nitrite reductases. This observation suggests that the absence of easily assimilated nitrogen sources, such as ammonium, enhances RDX degradation. Although specific end products of RDX degradation were not determined, the production of nitrous oxide (N2O) suggests that A. paludosum cleaved the triazine ring.
Environ Sci Technol, 2006
Fullerene research in biological systems has been hindered by the compound&am... more Fullerene research in biological systems has been hindered by the compound's relative insolubility in water. However, C60 molecules can be made to aggregate, forming stable fullerene water suspensions (FWS) whose properties differ from those of bulk solid C60. There are many different protocols for making FWS. This paper explores four of these methods and establishes the antibacterial activity of each resulting suspension, including a suspension made without intermediary solvents. The aggregates in each polydisperse suspension were separated by size using differential centrifugation and tested for antibacterial activity using Bacillus subtilis as a test organism. All suspensions exhibited relatively strong antibacterial activity. Fractions containing smaller aggregates had greater antibacterial activity, although the increase in toxicity was disproportionately higher than the associated increase in putative surface area. This suggests the need for improved understanding of the behavior of FWS towards organisms and in the environment to determine how C60 can be safely used and disposed.
Nano Letters, May 1, 2008
Fullerene research in biological systems has been hindered by the compound&am... more Fullerene research in biological systems has been hindered by the compound's relative insolubility in water. However, C60 molecules can be made to aggregate, forming stable fullerene water suspensions (FWS) whose properties differ from those of bulk solid C60. There are many different protocols for making FWS. This paper explores four of these methods and establishes the antibacterial activity of each resulting suspension, including a suspension made without intermediary solvents. The aggregates in each polydisperse suspension were separated by size using differential centrifugation and tested for antibacterial activity using Bacillus subtilis as a test organism. All suspensions exhibited relatively strong antibacterial activity. Fractions containing smaller aggregates had greater antibacterial activity, although the increase in toxicity was disproportionately higher than the associated increase in putative surface area. This suggests the need for improved understanding of the behavior of FWS towards organisms and in the environment to determine how C60 can be safely used and disposed.
Atlantica Xxii Revista Asturiana De Informacion Y Pensamiento, 2010