<?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>0122-5383</journal-id>
<journal-title><![CDATA[CT&F - Ciencia, Tecnología y Futuro]]></journal-title>
<abbrev-journal-title><![CDATA[C.T.F Cienc. Tecnol. Futuro]]></abbrev-journal-title>
<issn>0122-5383</issn>
<publisher>
<publisher-name><![CDATA[Instituto Colombiano del Petróleo (ICP) - ECOPETROL S.A.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0122-53832017000100049</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Aggregate structure analysis of colombian heavy crude oil-derived Asphaltenes using small angle X-ray scattering]]></article-title>
<article-title xml:lang="es"><![CDATA[Análisis de la estructura de agregados de Asfaltenos derivados de petróleo crudo pesado colombiano usando dispersión de rayos-X a bajo ángulo]]></article-title>
<article-title xml:lang="pt"><![CDATA[Análise da estrutura de agregados de Asfaltenos derivados de petróleo bruto pesado colombiano usando dispersão de raios-X de baixo ângulo]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Morante]]></surname>
<given-names><![CDATA[Lina R.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Poveda]]></surname>
<given-names><![CDATA[Juan C.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Montiel]]></surname>
<given-names><![CDATA[Raúl]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Henao]]></surname>
<given-names><![CDATA[José A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Industrial de Santander Escuela de Química Grupo de Investigación en Química Estructural, GIQUE]]></institution>
<addr-line><![CDATA[Bucaramanga ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Industrial de Santander Escuela de Química Laboratorio de Espectroscopia Atómica Molecular, LEAM]]></institution>
<addr-line><![CDATA[Bucaramanga ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad Autónoma Metropolitana Departamento de Física División de Ciencias Básicas e Ingeniería]]></institution>
<addr-line><![CDATA[México D.F Del. Iztapalapa]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<volume>6</volume>
<numero>5</numero>
<fpage>49</fpage>
<lpage>58</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0122-53832017000100049&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0122-53832017000100049&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0122-53832017000100049&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT Small-Angle X-ray Scattering (SAXS) technique was used to characterize the structure of Asphaltene aggregates as a function of its concentration in Toluene solutions. Asphaltene concentration ranged from 0.01 to 1% w/v. Solid Asphaltenes were obtained from a Colombian heavy crude oil following the ASTM D6560-12 standard method by precipitation with n-heptane. Structural properties were interpreted in terms of the radius of gyration   (Rg) and the power-law exponents (d). The obtained spectra for Asphaltene-Toluene systems allowed us to explore two regions. At low values of the scattering vector q (q &lt; 3 x 10-2), we found that Asphaltenes self-associate to form aggregates with fractal properties. These structures exhibit a particular transition from surface fractals to mass fractals as concentration increased. In the second one (q &gt; 3 x 10-2), scattering curves showed that Asphaltenes form small dense regions, in which the intensity of the scattered radiation rises with increasing concentration. The observed results demonstrate that Asphaltenes in Toluene solutions coexist as large scale aggregates and nanoaggregates, likewise these structures are conditioned by the Asphaltene concentration and self-association processes.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Se utilizó la técnica de dispersión de rayos X a bajo ángulo (SAXS) para caracterizar la estructura de agregados de Asfaltenos en función de su concentración en soluciones de tolueno. La concentración de Asfaltenos osciló entre 0,01 y 1% p/v. Se obtuvieron Asfaltenos sólidos a partir de un petróleo crudo pesado colombiano siguiendo el método estándar ASTM D6560-12 por precipitación con n-heptano. Las propiedades estructurales se interpretaron en términos del radio de giro   (Rg) y de los exponentes de ley de potencia (d). Los espectros obtenidos para los sistemas asfaltenos-tolueno nos permitieron explorar dos regiones. A valores bajos del vector de dispersión q (q &lt; 3 x 102), encontramos que los Asfaltenos se auto-asocian para formar agregados con propiedades fractales. Estas estructuras exhiben una transición particular de fractales de superficie a fractales de masa a medida que aumenta la concentración. En la segunda región (q &gt; 3 x 10-2), las curvas de dispersión mostraron que los Asfaltenos forman pequeñas regiones densas, en las que la intensidad de la radiación dispersada aumenta con el incremento de la concentración. Los resultados observados demuestran que los Asfaltenos en soluciones de tolueno coexisten como agregados a gran escala y nanoagregados, asimismo estas estructuras están condicionadas por la concentración de Asfaltenos y por procesos de auto-asociación.]]></p></abstract>
<abstract abstract-type="short" xml:lang="pt"><p><![CDATA[RESUMO Utilizou-se a técnica de dispersão de raios-X de baixo ângulo (SAXS) para definir a estrutura de agregados de asfaltenos em função da sua concentração em soluções de tolueno. A concentração de asfaltenos variou entre 0,01 e 1% p/v. Asfaltenos sólidos foram obtidos a partir de um petróleo bruto pesado colombiano seguindo o método padrão ASTM D6560-12 por precipitação com n-heptano. As propriedades estruturais foram interpretadas em termos do raio de giro (Rg) e dos expoentes de lei de potência (d). Os espectros obtidos para os sistemas asfalteno-tolueno possibilitaram explorar duas regiões. A valores baixos do vetor de dispersão q (q &lt; 3 a 10-2), descobrimos que os asfaltenos se unem por auto-associação para criar agregados com propriedades fractais. Essas estruturas mostram uma transição particular de fractais de superfície para fractais de massa enquanto aumenta a concentração. Na segunda região (q &gt; 3 a 102), as curvas de dispersão mostraram que os asfaltenos formam pequenas regiões densas, nas quais a intensidade da radiação dispersa aumenta com a elevação da concentração. Os resultados observados demostram que os asfaltenos em soluções de tolueno coexistem como agregados em grande escala e nanoagregados, do mesmo modo, essas estruturas estão condicionadas pela concentração de asfaltenos e por processos de auto-associação.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Colombian Asphaltenes]]></kwd>
<kwd lng="en"><![CDATA[Structural properties of aggregates]]></kwd>
<kwd lng="en"><![CDATA[Small Angle X-Ray Scattering]]></kwd>
<kwd lng="en"><![CDATA[Concentration effect]]></kwd>
<kwd lng="es"><![CDATA[Asfaltenos Colombianos]]></kwd>
<kwd lng="es"><![CDATA[Propiedades estructurales de agregados]]></kwd>
<kwd lng="es"><![CDATA[Rayos X de Ángulo Reducido de Dispersión]]></kwd>
<kwd lng="es"><![CDATA[Efecto de concentración]]></kwd>
<kwd lng="pt"><![CDATA[Asfaltenos Colombianos]]></kwd>
<kwd lng="pt"><![CDATA[Propriedades estruturais dos agregados]]></kwd>
<kwd lng="pt"><![CDATA[Dispersão de Raios-X a Baixo Ângulo]]></kwd>
<kwd lng="pt"><![CDATA[Efeito da concentração]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Amundaraín]]></surname>
<given-names><![CDATA[J. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Chodakowski]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Long]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[Shaw]]></surname>
<given-names><![CDATA[J. M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Characterization of Physically and Chemically Separated Athabasca Asphaltenes Using Small-Angle X-ray Scattering]]></article-title>
<source><![CDATA[Energy &amp; Fuels]]></source>
<year>2011</year>
<volume>25</volume>
<page-range>5100-12</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Andreatta]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Bostrom]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Mullins]]></surname>
<given-names><![CDATA[O. C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[High-Q Ultrasonic Determination of the Critical Nanoaggregate Concentration of Asphaltenes and the Critical Micelle Concentration of Standard Surfactants]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2005</year>
<volume>21</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>2728-36</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Avnir]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
</person-group>
<source><![CDATA[Fractal approach to heterogeneous chemistry. Surface, colloids, polymers]]></source>
<year>1989</year>
<edition>1st</edition>
<publisher-loc><![CDATA[Chichester ]]></publisher-loc>
<publisher-name><![CDATA[Wiley]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Beaucage]]></surname>
<given-names><![CDATA[G. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Small-Angle Scattering from Polymeric Mass Fractals of Arbitrary Mass-Fractal Dimension]]></article-title>
<source><![CDATA[Journal of Applied Crystallography]]></source>
<year>1996</year>
<volume>29</volume>
<page-range>134-46</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Dickie]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Yen]]></surname>
<given-names><![CDATA[T. F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Macrostructures of asphaltic fractions by various instrumental methods]]></article-title>
<source><![CDATA[Analytical Chemistry]]></source>
<year>1967</year>
<volume>39</volume>
<page-range>1847-52</page-range></nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Espinat]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Rosenberg]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Scarsella]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Barre]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Fenistein]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Broseta]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Colloidal structural evolution from stable to flocculated state of Asphaltene solutions and heavy crudes]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Mullins]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<name>
<surname><![CDATA[Sheu]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
</person-group>
<source><![CDATA[Structures and Dynamics of Asphaltenes]]></source>
<year>1998</year>
<page-range>1452-01</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Eyssautier]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Levitz]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Espinat]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Jestin]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Gummel]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Grillo]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Barr]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Insight into Asphaltene Nanoaggregates Structure Inferred by Small Angle Neutron and X-ray Scattering]]></article-title>
<source><![CDATA[The Journal of Physical Chemistry B]]></source>
<year>2011</year>
<volume>115</volume>
<page-range>6827-37</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gawrys]]></surname>
<given-names><![CDATA[K. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Blankenship]]></surname>
<given-names><![CDATA[G. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Kilpatrick]]></surname>
<given-names><![CDATA[P. K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Solvent Entrainment in and Flocculation of Asphaltenic Aggregates Probed by Small-Angle Neutron Scattering]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2006</year>
<volume>22</volume>
<page-range>4487-97</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Guinier]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Fournet]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<source><![CDATA[Small angle scattering of X-rays]]></source>
<year>1955</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Jhon Wiley &amp; Sons]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hammersley]]></surname>
<given-names><![CDATA[A. P]]></given-names>
</name>
</person-group>
<source><![CDATA[FIT2D: An Introduction and Overview; ESRF Internal Report ESRF97HA02T]]></source>
<year>1997</year>
<publisher-loc><![CDATA[Sydney ]]></publisher-loc>
<publisher-name><![CDATA[Mathematics Department, Macquarie University]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Headen]]></surname>
<given-names><![CDATA[T. F.]]></given-names>
</name>
<name>
<surname><![CDATA[Boek]]></surname>
<given-names><![CDATA[E. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Stellbrink]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Scheven]]></surname>
<given-names><![CDATA[U. M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Small Angle Neutron Scattering (SANS and V-SANS) Study of Asphaltene Aggregates in Crude Oil]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2009</year>
<volume>25</volume>
<page-range>422-8</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hiemenz]]></surname>
<given-names><![CDATA[P. C.]]></given-names>
</name>
<name>
<surname><![CDATA[Rajagopalan]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[Principles of Colloid and Surface Chemistry]]></source>
<year>1997</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Marcel Dekker]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hoepfner]]></surname>
<given-names><![CDATA[M. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Vilas Bôas FáVero]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Haji-Akbari]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Fogler]]></surname>
<given-names><![CDATA[H. S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The Fractal Aggregation of Asphaltenes]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2013</year>
<volume>29</volume>
<numero>28</numero>
<issue>28</issue>
<page-range>8799-808</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Leontaritis]]></surname>
<given-names><![CDATA[K.J.]]></given-names>
</name>
<name>
<surname><![CDATA[Mansoori]]></surname>
<given-names><![CDATA[G.A]]></given-names>
</name>
</person-group>
<source><![CDATA[Asphaltene Flocculation during Oil Production and Processing: a Thermodynamic Collodial Model]]></source>
<year>1987</year>
<conf-name><![CDATA[ SPE International Symposium on Oilfield Chemistry]]></conf-name>
<conf-date>4-6 February 1987</conf-date>
<conf-loc>San Antonio </conf-loc>
<page-range>149-58</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martin]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Hurd]]></surname>
<given-names><![CDATA[A. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Scattering from Fractals]]></article-title>
<source><![CDATA[Journal of Applied Crystallography]]></source>
<year>1987</year>
<volume>20</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>61-78</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Meakin]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Family]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Structure and dynamics of reaction-limited aggregation]]></article-title>
<source><![CDATA[Physical Review A]]></source>
<year>1987</year>
<volume>36</volume>
<numero>11</numero>
<issue>11</issue>
<page-range>5498-501</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Morimoto]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Morita]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Takanohashi]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Nishikawa]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Specific Asphaltene Aggregation in Toluene at Around 50 mg/L]]></article-title>
<source><![CDATA[Journal of the Japan Petroleum Institute]]></source>
<year>2013</year>
<volume>56</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>58-9</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mullins]]></surname>
<given-names><![CDATA[O. C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The Modified Yen Model]]></article-title>
<source><![CDATA[Energy &amp; Fuels]]></source>
<year>2010</year>
<volume>24</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>2179-207</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Narayanan]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Synchroton Small-Angle X-Ray Scattering]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Borsali]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Pecora]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<source><![CDATA[Soft Matter Characterization]]></source>
<year>2008</year>
<volume>1</volume>
<page-range>899-952</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nellensteyn]]></surname>
<given-names><![CDATA[F. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The constitution of asphalt]]></article-title>
<source><![CDATA[Journal of the Institute of Petroleum]]></source>
<year>1924</year>
<volume>10</volume>
<page-range>311-25</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Pfeiffer]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Saal]]></surname>
<given-names><![CDATA[R. N. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Asphaltic bitumen as colloid system]]></article-title>
<source><![CDATA[The Journal of Physical Chemistry]]></source>
<year>1940</year>
<volume>44</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>139-49</page-range></nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Roux]]></surname>
<given-names><![CDATA[J. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Broseta]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Deme]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[SANS Study of Asphaltene Aggregation: Concentration and Solvent Quality Effects]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2001</year>
<volume>17</volume>
<numero>16</numero>
<issue>16</issue>
<page-range>5085-92</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sakai]]></surname>
<given-names><![CDATA[V. G.]]></given-names>
</name>
<name>
<surname><![CDATA[Alba-Simionesco]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[S. H]]></given-names>
</name>
</person-group>
<source><![CDATA[Dynamics of Soft Matter: Neutron Applications]]></source>
<year>2011</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Springer Science+Business Media]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sheu]]></surname>
<given-names><![CDATA[E. Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Self-association of Asphaltenes: Structural and Molecular Packing]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Mullins]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<name>
<surname><![CDATA[Sheu]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
</person-group>
<source><![CDATA[Structures and Dynamics of Asphaltenes]]></source>
<year>1998</year>
<page-range>115-44</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Springer]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B25">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sheu]]></surname>
<given-names><![CDATA[E. Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Acevedo]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Effect of Pressure and Temperature on Colloidal Structure of Furrial Crude Oil]]></article-title>
<source><![CDATA[Energy &amp; Fuels]]></source>
<year>2001</year>
<volume>15</volume>
<page-range>702-7</page-range></nlm-citation>
</ref>
<ref id="B26">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sheu]]></surname>
<given-names><![CDATA[E. Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Small Angle Scattering and Asphaltenes]]></article-title>
<source><![CDATA[Journal of Physics: Condensed Matter]]></source>
<year>2006</year>
<volume>18</volume>
<page-range>S2485-98</page-range></nlm-citation>
</ref>
<ref id="B27">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Speight]]></surname>
<given-names><![CDATA[J. G]]></given-names>
</name>
</person-group>
<source><![CDATA[The Chemistry and Technology of Petroleum]]></source>
<year>2010</year>
<edition>4th</edition>
<publisher-loc><![CDATA[Boca Raton ]]></publisher-loc>
<publisher-name><![CDATA[CRC Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B28">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tanaka]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Hunt]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Winans]]></surname>
<given-names><![CDATA[R. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Thiyagarajan]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Sato]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Takanohashi]]></surname>
<given-names><![CDATA[T]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Aggregates Structure Analysis of Petroleum Asphaltenes with Small-Angle Neutron Scattering]]></article-title>
<source><![CDATA[Energy &amp; Fuels]]></source>
<year>2003</year>
<volume>17</volume>
<page-range>127-34</page-range></nlm-citation>
</ref>
<ref id="B29">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Weitz]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Huang]]></surname>
<given-names><![CDATA[J. S.]]></given-names>
</name>
<name>
<surname><![CDATA[Lin]]></surname>
<given-names><![CDATA[M. Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Sung]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Dynamics of diffusion-limited kinetic aggregation]]></article-title>
<source><![CDATA[Physical Review Letters]]></source>
<year>1984</year>
<volume>53</volume>
<numero>17</numero>
<issue>17</issue>
<page-range>1657-60</page-range></nlm-citation>
</ref>
<ref id="B30">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yarranton]]></surname>
<given-names><![CDATA[H. W.]]></given-names>
</name>
<name>
<surname><![CDATA[Ortiz]]></surname>
<given-names><![CDATA[D. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Barrera]]></surname>
<given-names><![CDATA[D. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Baydak]]></surname>
<given-names><![CDATA[E. N.]]></given-names>
</name>
<name>
<surname><![CDATA[Barré]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Frot]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Eyssautier]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Zeng]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
<name>
<surname><![CDATA[Xu]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Dechaine]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Becerra]]></surname>
<given-names><![CDATA[J. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Shaw]]></surname>
<given-names><![CDATA[A. M.]]></given-names>
</name>
<name>
<surname><![CDATA[McKenna]]></surname>
<given-names><![CDATA[M. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Mapolelo]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Bohne]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
<name>
<surname><![CDATA[Yang]]></surname>
<given-names><![CDATA[Oake J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[On the size distribution of self-associated Asphaltenes]]></article-title>
<source><![CDATA[Energy &amp; Fuels]]></source>
<year>2013</year>
<volume>27</volume>
<numero>9</numero>
<issue>9</issue>
<page-range>5083-106</page-range></nlm-citation>
</ref>
<ref id="B31">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yen]]></surname>
<given-names><![CDATA[T. F.]]></given-names>
</name>
<name>
<surname><![CDATA[Erdman]]></surname>
<given-names><![CDATA[J. G.]]></given-names>
</name>
<name>
<surname><![CDATA[Pollack]]></surname>
<given-names><![CDATA[S. S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Investigation of the Structure of Petroleum Asphaltenes by X-Ray Diffraction]]></article-title>
<source><![CDATA[Analytical Chemistry]]></source>
<year>1961</year>
<volume>33</volume>
<numero>11</numero>
<issue>11</issue>
<page-range>1587-94</page-range></nlm-citation>
</ref>
<ref id="B32">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zielinski]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Saha]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Freed]]></surname>
<given-names><![CDATA[D. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Hürlimann]]></surname>
<given-names><![CDATA[M. D.]]></given-names>
</name>
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Probing Asphaltene aggregation in native crude oils with low-field NMR]]></article-title>
<source><![CDATA[Langmuir]]></source>
<year>2010</year>
<volume>26</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>5014-21</page-range></nlm-citation>
</ref>
<ref id="B33">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zimm]]></surname>
<given-names><![CDATA[B. H]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The Scattering of Light and the Radial Distribution Function of High Polymer Solutions]]></article-title>
<source><![CDATA[The Journal of Chemical Physics]]></source>
<year>1948</year>
<volume>16</volume>
<numero>12</numero>
<issue>12</issue>
<page-range>1093-9</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
