Chemistry Substance
Mostrando 13-20 de 20 artigos, teses e dissertações.
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13. Study abaout the determination of benzene and ammonia in air using quartz piezoeletric sensor. / Estudo sobre a determinação de benzeno e amônia no ar, utlizando sensor piezelétrico de quartzo
The objective of this work was to study, develop and evaluate coatings for detecting benzene and ammonia in atmospheric air, by using a piezoelectric quartz sensor. Nowadays, piezoelectric quartz sensors are very important in Analytical Chemistry due to their numerous aplications (in gaseous fase or in solution). This method is based on the fact that the qua
Publicado em: 2005
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14. Iron oxide based nanoparticles: synthesis and characterization / Síntese e caracterização de nanopartículas baseadas em óxidos de ferro
Magnetic nanoparticles have importance in several areas of knowledge including physics, chemistry and biology. Obtaining nanomaterials with well defined characteristic and shapes is a great challenge for this area of research. In this work two synthetic processes for the synthesis of the magnetic nanoparticles were developed, in reversed micelles and sol-gel
Publicado em: 2005
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15. Síntese e caracterização de substâncias semelhantes aos ácidos húmicos de carvão de eucalipto, e sua interação com diclorofenol, cálcio, manganês e alumínio / Synthesis and characterization of humic acid-like substances from eucalypt charcoal, and its interaction with diclorofenol, calcium, manganese and aluminium
A wide range of commercial products containing humic substances have been applied successfully in agricultural and environmental remediation systems. Regarding their beneficial remediation characteristics, there is a high potential to adsorb heavy metals and organic pollutants, thus reducing their bioavailability. Industrially, they are extracted from non-re
Publicado em: 2005
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16. Shabat e a conservaÃÃo do judaÃsmo. O sÃtimo dia faz renascer a quintessÃncia e a partÃcula elementar do universo
This study deals with the Jewish ritual of the Sabbath here seen as a passing ritual from the profane to the sacred. Sabbath, which in Hebrew means to cease, corresponds to the seventh day, the Saturday. Since in the Jewish calendar the day begins in the end of the afternoon, the Sabbath has its start in the Fridayâs sunset, during until the Saturdayâs sun
Publicado em: 2003
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17. Caracterização do material particulado inalavel (MP10) na atmosfera de Paulinia e região
The present work evaluated the particulate matter (PM10) emission contributions of the Replan catalytic cracking plant in the inhalable particulate matter (PM10) of the region affected by the refinery. To separate the contribution of the source under investigation from other sources that contribute to the particulate matter in suspension, the receptor model
Publicado em: 2003
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18. Estudo quimico da unidade de tratamento de gas liquifeito de petroleo (GLP) e gas combustivel (GC) e tentativas de sintese da pirazinamida
The object of this work was to solve some interesting problems in applied chemistry, one in the petrochemical area and anoyher in the area of pharmaceutical chemistry. In the petrochemical area we studied solutions of diethanolamine that is used currently in Fluid Catalyt Craking (FCC) plants for the elimination of acidic gases from fuel gas (FC) and liquid
Publicado em: 1988
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19. The Chemistry of Olfactory Reception: Stimulus-Specific Protection from Sulfhydryl Reagent Inhibition
The group-specific protein reagent, N-ethylmaleimide, irreversibly blocks the electrical response of the olfactory receptor organ of the frog to odorous stimuli. If the odorous substance, ethyl n-butyrate, in concentrations high enough to saturate the receptor system, is present in the nasal cavity before and during a brief exposure to N-ethylmaleimide, the
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20. The importance of being discrete: Life always wins on the surface
Many systems in chemistry, biology, finance, and social sciences present emerging features that are not easy to guess from the elementary interactions of their microscopic individual components. In the past, the macroscopic behavior of such systems was modeled by assuming that the collective dynamics of microscopic components can be effectively described col
The National Academy of Sciences.