<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1870-249X</journal-id>
<journal-title><![CDATA[Journal of the Mexican Chemical Society]]></journal-title>
<abbrev-journal-title><![CDATA[J. Mex. Chem. Soc]]></abbrev-journal-title>
<issn>1870-249X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Química de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-249X2005000400003</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Ozone Trend Analysis at Pedregal Station in the Metropolitan Area of Mexico City]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Garfias Vázquez]]></surname>
<given-names><![CDATA[Margarita]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Audry Sánchez]]></surname>
<given-names><![CDATA[Javier]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Garfias y Ayala]]></surname>
<given-names><![CDATA[Francisco Javier]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Nacional Autónoma de México Facultad de Química ]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2005</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2005</year>
</pub-date>
<volume>49</volume>
<numero>4</numero>
<fpage>322</fpage>
<lpage>323</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-249X2005000400003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-249X2005000400003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-249X2005000400003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Pedregal Station is located in a residential area in the southwest portion of Mexico City, where the worst ozone episodes are registered. Three models for forecasting ozone are analyzed based on the 19 mean semester maximum values of daily ozone registered at Pedregal Station. The logarithm model seems to fit best the available data. Its use suggests that near 10 years have to elapse fom July 2005, before air quality is recovered. Additional control measures are suggested, such as, doubling concentration of MTBE, reducing gasoline Reid Vapor Pressure from 7.5 to 7 psia and increasing efficiency and cover of the public transport system, but reinforcing the present control policies.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[En la estación de Pedregal, localizada en la zona residencial de la región suroeste de la Ciudad de México, se registran los peores episodios de ozono. Se analizan tres modelos para pronosticar ozono sobre la base de los 19 datos del valor medio semestral de la máxima concentración diaria de ozono registrados en la estación de Pedregal. El modelo logarítmico es el que se ajusta mejor a los datos disponibles. Su uso sugiere que se requieren cerca de 10 años a partir de julio 2005, para recuperar la calidad del aire respecto al ozono. Se sugieren medidas adicionales de control, tales como doblar la concentración de MTBE, reducir la presión de vapor de la gasolina Reid de 7.5 a 7.0 psia e incrementar la eficiencia y cobertura del transporte público, pero reforzando las medidas actuales.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Forecasting ozone]]></kwd>
<kwd lng="en"><![CDATA[Pedregal Station]]></kwd>
<kwd lng="en"><![CDATA[MTBE]]></kwd>
<kwd lng="en"><![CDATA[Reid Vapor Pressure]]></kwd>
<kwd lng="es"><![CDATA[Predicción de ozono]]></kwd>
<kwd lng="es"><![CDATA[Estación de Pedregal]]></kwd>
<kwd lng="es"><![CDATA[MTBE]]></kwd>
<kwd lng="es"><![CDATA[Presión de Vapor Reid]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Article </font></p>  	    <p align="justify">&nbsp;</p>  	    <p align="center"><font face="verdana" size="4"><b>Ozone Trend Analysis at Pedregal Station in the Metropolitan Area of Mexico City</b></font></p>     <p align="center">&nbsp;</p>  	    <p align="center"><font face="verdana" size="2"><b>Margarita Garfias V&aacute;zquez, Javier Audry S&aacute;nchez, and Francisco Javier Garfias y Ayala*</b></font></p>     <p align="center">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><i>Facultad de Qu&iacute;mica, Universidad Nacional Aut&oacute;noma de M&eacute;xico, M&eacute;xico, Ciudad Universitaria, M&eacute;xico D. F.</i> <a href="mailto:jgarfias@servidor.unam.mx" target="_blank">jgarfias@servidor.unam.mx</a></font></p>     <p align="justify">&nbsp;</p>  	    <p align="justify"><font face="verdana" size="2">Recibido el 6 de junio del 2005.    ]]></body>
<body><![CDATA[<br>     Aceptado el 20 de octubre del 2005.</font></p> 	    <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>Abstract</b> </font></p>     <p align="justify"><font face="verdana" size="2">Pedregal Station is located in a residential area in the southwest portion of Mexico City, where the worst ozone episodes are registered. Three models for forecasting ozone are analyzed based on the 19 mean semester maximum values of daily ozone registered at Pedregal Station. The logarithm model seems to fit best the available data. Its use suggests that near 10 years have to elapse fom July 2005, before air quality is recovered. Additional control measures are suggested, such as, doubling concentration of MTBE, reducing gasoline Reid Vapor Pressure from 7.5 to 7 psia and increasing efficiency and cover of the public transport system, but reinforcing the present control policies.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Key words:</b> Forecasting ozone, Pedregal Station, MTBE, Reid Vapor Pressure.</font></p> 	    <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>Resumen</b> </font></p>     <p align="justify"><font face="verdana" size="2">En la estaci&oacute;n de Pedregal, localizada en la zona residencial de la regi&oacute;n suroeste de la Ciudad de M&eacute;xico, se registran los peores episodios de ozono. Se analizan tres modelos para pronosticar ozono sobre la base de los 19 datos del valor medio semestral de la m&aacute;xima concentraci&oacute;n diaria de ozono registrados en la estaci&oacute;n de Pedregal. El modelo logar&iacute;tmico es el que se ajusta mejor a los datos disponibles. Su uso sugiere que se requieren cerca de 10 a&ntilde;os a partir de julio 2005, para recuperar la calidad del aire respecto al ozono. Se sugieren medidas adicionales de control, tales como doblar la concentraci&oacute;n de MTBE, reducir la presi&oacute;n de vapor de la gasolina Reid de 7.5 a 7.0 psia e incrementar la eficiencia y cobertura del transporte p&uacute;blico, pero reforzando las medidas actuales.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> Predicci&oacute;n de ozono, Estaci&oacute;n de Pedregal, MTBE, Presi&oacute;n de Vapor Reid.</font></p>  	    <p align="justify">&nbsp;</p> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2"><a href="../pdf/jmcs/v49n4/v49n4a3.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p> 	    <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><b>References</b></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">1.&nbsp;Garfias&#45;V&aacute;zquez, M.; Audry&#45;S&aacute;nchez, J.; Garfias&#45;Ayala, F. J. <i>J. Mex. Chem. Soc.</i> <b>2005</b>, <i>59</i>, 3&#45;10.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4892487&pid=S1870-249X200500040000300001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">2.&nbsp;Molina, L.; Molina, M. <i>Air Quality in the M&eacute;xico Megacity,</i> Kluwer Academic Publishers, The Netherlands, <b>2002</b>, 384.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4892489&pid=S1870-249X200500040000300002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>  	    <!-- ref --><p align="justify"><font face="verdana" size="2">3.&nbsp;Garfias&#45;Ayala, F. J.; D&iacute;az&#45;Guti&eacute;rrez, L. <i>Gasolinas Oxigenadas: La experiencia mexicana,</i> Fondo de Cultura Econ&oacute;mica, M&eacute;xico, <b>2003</b>.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4892491&pid=S1870-249X200500040000300003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">4.&nbsp;Huesca, R.; Garfias&#45;Ayala, F. J. "La Gasolina del Valle de M&eacute;xico". In: <i>Contaminaci&oacute;n Atmosf&eacute;rica,</i> Garc&iacute;a&#45;Col&iacute;n L.; Varela&#45;Ham J. R., Editors; El Colegio Nacional, M&eacute;xico, <b>2001</b>; </font><font face="verdana" size="2">1&#45;33.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4892493&pid=S1870-249X200500040000300004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body><back>
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</article>
