<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:dc="http://purl.org/dc/elements/1.1/" version="2.0">
  <channel>
    <title>DSpace Collection:</title>
    <link>https://repositorio.ufu.br/handle/123456789/20867</link>
    <description />
    <pubDate>Wed, 15 Apr 2026 10:49:32 GMT</pubDate>
    <dc:date>2026-04-15T10:49:32Z</dc:date>
    <item>
      <title>Integração de dados aerogeofísicos e geológicos aplicados na prospecção de potássio nas adjacências de Sacramento - MG</title>
      <link>https://repositorio.ufu.br/handle/123456789/48364</link>
      <description>Title: Integração de dados aerogeofísicos e geológicos aplicados na prospecção de potássio nas adjacências de Sacramento - MG
Abstract: This study investigates potential sites for potassium prospecting in the Sacramento region of Minas Gerais, aiming to reduce Brazil's dependence on imports of this resource, which is crucial for agricultural fertilizers. The research began with a literature review and the establishment of clear objectives, followed by a description of the methodology, which highlights the use of Geographic Information Systems (GIS) for processing and integrating geophysical and geological data. Aerogeophysical and geological methods were employed to integrate gamma-spectrometric data (potassium channel) with field mapping, with the goal of identifying promising areas for potassium prospecting. The data were processed using Oasis Montaj software, which helped identify potential targets, particularly zones with high potassium concentrations known as verdetes. The results reveal that the study area exhibits geophysical anomalies that correlate with significant potassium concentrations, indicating possible exploration potential. Seven promising targets were delineated, with emphasis on Target G, where mineralization occurs at shallow depths with significant K₂O grades (between 5% and 18%). Field confirmation, including geological mapping and drilling, validated the method's effectiveness, with 17 out of 20 drill holes yielding positive results. It is concluded that the integration of geophysical and geological data optimizes mineral prospecting, reduces costs, and indicates the area is viable for the economic exploitation of potassium.</description>
      <pubDate>Fri, 19 Sep 2025 00:00:00 GMT</pubDate>
      <guid isPermaLink="false">https://repositorio.ufu.br/handle/123456789/48364</guid>
      <dc:date>2025-09-19T00:00:00Z</dc:date>
    </item>
    <item>
      <title>Mapeamento geológico de uma porção oeste no Domo Serra Negra, Patrocínio – MG: um trabalho voltado para potencialidade na exploração mineral</title>
      <link>https://repositorio.ufu.br/handle/123456789/48107</link>
      <description>Title: Mapeamento geológico de uma porção oeste no Domo Serra Negra, Patrocínio – MG: um trabalho voltado para potencialidade na exploração mineral</description>
      <pubDate>Fri, 19 Sep 2025 00:00:00 GMT</pubDate>
      <guid isPermaLink="false">https://repositorio.ufu.br/handle/123456789/48107</guid>
      <dc:date>2025-09-19T00:00:00Z</dc:date>
    </item>
    <item>
      <title>Evolução textural e mineralógica de concretos submetidos a diferentes estágios de degradação de reação álcali agregado e formação de etringita tardia</title>
      <link>https://repositorio.ufu.br/handle/123456789/48058</link>
      <description>Title: Evolução textural e mineralógica de concretos submetidos a diferentes estágios de degradação de reação álcali agregado e formação de etringita tardia
Abstract: The present study aimed to study the textural and mineralogical evolution of 29 concrete &#xD;
specimens. These specimens were subjected to deterioration processes, such as alkali-aggregate &#xD;
reaction and late ettringite formation, for periods of 28 and 200 days. The mineralogical &#xD;
characterization aimed to infer which minerals participated in the reactions, as well as the &#xD;
evolution of the modal composition of the samples in relation to time. The textural analysis, &#xD;
performed on the same specimens applying the Damage Rating Index (DRI) method, allowed &#xD;
the evaluation and identification of the degree of concrete deterioration and the pathologies &#xD;
involved, by quantifying the fractures. The study was divided into the following stages: &#xD;
literature review (1), application of the DRI (2), petrography (3) and analysis and discussion of &#xD;
the data (4). The textural analysis revealed the predominance of unfilled fractures in the coarse &#xD;
aggregates, in the 28-day specimens for the AAR. In the 200-day period, fractures filled by the &#xD;
reaction product in the coarse aggregates are formed, reaching an expansion of 0.06%. The &#xD;
same textural characteristics were observed in the test specimens subjected to late ettringite &#xD;
formation at 28 days, mainly fractures found in the aggregate because the reaction does not &#xD;
occur in the stipulated time, but at 200 days the fractures develop in the paste, reaching an &#xD;
expansion of 0.03%; however, with a predominance of fractures in the aggregate, it is &#xD;
noteworthy that these fractures are not due to the formation of late ettringite. From the &#xD;
petrographic analysis, it was possible to verify the presence of deleterious minerals such as &#xD;
quartz and devitrified material, as well as the reaction products at 200 days. In view of this, it &#xD;
was argued that the alkali-aggregate reaction occurs more effectively than the DEF pathology, &#xD;
since the DRI values found at 200 days were at least 219, while the DEF reached its maximum &#xD;
at 154.75; The RAA samples exhibited an average DRI value of 225.75 at 200 days, and the &#xD;
RR samples 238.5, showing similar DRI values, although the RR specimens were not &#xD;
manufactured with the intention of the reaction occurring in an accelerated manner, indicating &#xD;
high reactivity of the material. For DEF, the initial heat treatment proved to be important, since &#xD;
an effective difference was observed in the average DRI values (148), when compared to the &#xD;
RI values of 108.5 at 200 days. It was also possible to define the reactive potential for the &#xD;
pathological manifestation of RAA even in DEF concretes, due to the presence of deleterious &#xD;
minerals that can help the reaction. In this way, it was possible to identify the mineral phases&#xD;
that contribute to the reactions, as well as the modal relationship of the specimens that do not &#xD;
show an effective change in the coarse aggregates and in the paste.</description>
      <pubDate>Fri, 22 Nov 2024 00:00:00 GMT</pubDate>
      <guid isPermaLink="false">https://repositorio.ufu.br/handle/123456789/48058</guid>
      <dc:date>2024-11-22T00:00:00Z</dc:date>
    </item>
    <item>
      <title>Análise preliminar da leitura e identificação do mapa geológico</title>
      <link>https://repositorio.ufu.br/handle/123456789/48018</link>
      <description>Title: Análise preliminar da leitura e identificação do mapa geológico</description>
      <pubDate>Mon, 18 Nov 2024 00:00:00 GMT</pubDate>
      <guid isPermaLink="false">https://repositorio.ufu.br/handle/123456789/48018</guid>
      <dc:date>2024-11-18T00:00:00Z</dc:date>
    </item>
  </channel>
</rss>

