<?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>2007-0934</journal-id>
<journal-title><![CDATA[Revista mexicana de ciencias agrícolas]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Mex. Cienc. Agríc]]></abbrev-journal-title>
<issn>2007-0934</issn>
<publisher>
<publisher-name><![CDATA[Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-09342014001001397</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Metodología para obtener ácidos húmicos y fulvicos y su caracterización mediante espectrofotometría infrarroja]]></article-title>
<article-title xml:lang="en"><![CDATA[Humic and fulvic acid extraction method and characterization by infrared spectrophotometry]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-Salazar]]></surname>
<given-names><![CDATA[Rubén]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González-Cervantes]]></surname>
<given-names><![CDATA[Guillermo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vázquez-Alvarado]]></surname>
<given-names><![CDATA[Rigoberto Eustacio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Olivares-Sáenz]]></surname>
<given-names><![CDATA[Emilio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vidales-Contreras]]></surname>
<given-names><![CDATA[Juan Antonio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Carranza de la Rosa]]></surname>
<given-names><![CDATA[Roberto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ortega-Escobar]]></surname>
<given-names><![CDATA[Manuel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,UANL CienciasAgrícolas Subdirección de Estudios de Posgrado]]></institution>
<addr-line><![CDATA[Marín Nuevo León]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,INIFAP CENID RASPA]]></institution>
<addr-line><![CDATA[Gómez Palacio Durango]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,UANL Facultad de Agronomía ]]></institution>
<addr-line><![CDATA[Marín Nuevo León]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Colegio de Posgraduados  ]]></institution>
<addr-line><![CDATA[Texcoco Estado de México]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2014</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2014</year>
</pub-date>
<volume>5</volume>
<numero>spe8</numero>
<fpage>1397</fpage>
<lpage>1407</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-09342014001001397&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-09342014001001397&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-09342014001001397&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Los extractos orgánicos en la actualidad tienen gran aceptación por los productores agrícolas fundamentalmente por su costo y al éxito de sus aplicaciones en los cultivos, con el fin de obtener un compuesto orgánico-mineral o humato como alternativa para eficientar los nutrientes a los cultivos, se recolectó un mineral fósil oigánico de una mina, en laboratorio se extrajeron las fracciones de ácido húmico (AH) y fúlvico (AF). Después se ajustó el pH de estos ácidos con fertilizantes químicos. Para los ácidos húmicos y fúlvicos se manejó un pH de 6, 7, 8 y 4, 6, 7 respectivamente y finalmente se solidificaron. Para la caracterización de los grupos funcionales de estos ácidos se utilizó un espectrómetro de luz infrarroja (IR). Los resultados muestran que ácidos húmicos y fúlvicos presentan grupos funcionales similares pero en cantidad diferente, la mezcla orgánico-mineral de AH y AF mostraron un comportamiento similar en adsorción del elemento incorporado, sin embargo el AH y AF ambos con pH 7 presentaron la mayor adsorción del Ca y Fe, esto se debe a que son compuestos pH dependientes y la capacidad de agrupamiento se debe a la reacción de intercambio catiónico dada por los radicales libres.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Organic extracts are now widely accepted by farmers mainly because of cost and success of their applications in crops, in order to obtain an organic-mineral complex or humate as an alternative for efficient delivery of nutrients to crops, an organic fossil mineral was collected from a mine, humic acid (HA) and fulvic (FA) fractions were extracted in the laboratory. The pH of these acids was adjusted with chemical fertilizers. For humic and fulvic acids pH 6, 7, 8 and 4, 6, 7 was handled respectively and finally solidified. Functional groups of these acids were characterized by an infrared spectrometer (IR). Results show that humic and fulvic acids have similar functional groups but different amount, the organo-mineral mixture of HA and FA showed a similar behavior in adsorption of the added element, however both HA and FA at pH 7 showed the highest Ca and Fe adsorption, since they are pH dependent compounds and complex formation is due to the cation exchange reaction by free radicals.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[extractos orgánicos]]></kwd>
<kwd lng="es"><![CDATA[grupos funcionales]]></kwd>
<kwd lng="es"><![CDATA[orgánico-mineral]]></kwd>
<kwd lng="en"><![CDATA[organic extracts]]></kwd>
<kwd lng="en"><![CDATA[functional groups]]></kwd>
<kwd lng="en"><![CDATA[organic-mineral]]></kwd>
</kwd-group>
</article-meta>
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