Benzene
Mostrando 25-36 de 555 artigos, teses e dissertações.
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25. Experimental Multi-scale analysis of Carbon/Epoxy Composites Nano-Reinforced by Carbon Nanotubes/Multi-layer Graphene
Nano-size structures, nanotubes/multi-layer graphene (CNT/MLG), were dispersed into epoxy system by a combination of sonication and high shear mixing. To avoid CNT/MLG agglomeration, a non-covalent functionalization were performed using surfactants, CO890 - Polyoxyethylene (40) nonylphenyl ether and SDBS - sodium dodecyl benzene sulfonate. Raman spectroscopy
Mat. Res.. Publicado em: 22/01/2018
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26. Studies on the Synthesis of Vitamin D Analogs with Aromatic D-Ring
ABSTRACT Herein, we describe our studies on the synthesis of 1α,25-dihydroxyvitamin D3 analogs possessing a benzene ring replacing the natural 5-membered D-ring by the Wittig-Horner and dienyne approaches. A key feature is the synthesis of a Cr(CO)3-complexed previtamin D derivative that enables the construction of vitamin D analogs with aromatic D-ring thr
An. Acad. Bras. Ciênc.. Publicado em: 2018
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27. Natural decomposition of hornbeam wood decayed by the white rot fungus Trametes versicolor
ABSTRACT The impacts of white-rot fungi on altering wood chemistry have been studied mostly in vitro. However, in vivo approaches may enable better assessment of the nature of interactions between saprotrophic fungi and host tree in nature. Hence, decayed and sound wood samples were collected from a naturally infected tree (Carpinus betulus L.). Fruiting bod
An. Acad. Bras. Ciênc.. Publicado em: 07/12/2017
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28. Cytotoxicity and genotoxicity of stilbene derivatives in CHO-K1 and HepG2 cell lines
Abstract The cytotoxicity and genotoxicity of the stilbenes (E)-methyl-4-(3-5-dimethoxystyryl)benzoate (ester), (E)-4-(3-5-dimethoxystyryl)aniline (amino), (Z)-1,3-dimethoxy-5-(4-methoxystyryl)benzene (cis-TMS) and (E)-1,3-dimethoxy-5-(4-methoxystyryl)benzene (trans-TMS) were investigated in this work. Structural modifications of resveratrol, a naturally occ
Genet. Mol. Biol.. Publicado em: 10/07/2017
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29. Degradation of monoaromatics by Bacillus pumilus MVSV3
ABSTRACT Monoaromatics, such as benzene, toluene, ethylbenzene and xylene (BTEX), are simple aromatic compound that are highly toxic due to their high solubility nature. Many chemical and physical methods for their degradation and breakup into nontoxic products are available, but still use of microorganism is preferred over these processes. In this present s
Braz. arch. biol. technol.. Publicado em: 22/06/2017
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30. Concentration Profiles of Regulated and Unregulated Pollutants Emitted from the Combustion of Soybean Biodiesel and Diesel/Biodiesel Blend Originating of a Diesel Cycle Engine
This study evaluated the concentration profiles of regulated and unregulated pollutants emitted from a stationary diesel engine cycle, operating at the speed of 1800 rpm and 0% load, using biofuels and binary blends. The experimental test considered fuel burning time on three different periods and storage times. The operation of the engine when it is still c
J. Braz. Chem. Soc.. Publicado em: 2017-04
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31. Effect of Sulfamic Acid on 1,3-Dipolar Cycloaddition Reaction: Mechanistic Studies and Synthesis of 4-Aryl-NH-1,2,3-triazoles from Nitroolefins
A facile and new metal-free 1,3-dipolar cycloaddition reaction for the synthesis of 4-aryl-NH-1,2,3-triazoles from nitroolefins and NaN3 employing NH2SO3H has been developed. Sulfamic acid proved to be an efficient additive in this transformation by inhibiting the formation of triaryl benzene. Mechanistic aspects and key intermediates associated with this tr
J. Braz. Chem. Soc.. Publicado em: 2017-04
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32. Quantificação de alquilbenzeno linear sulfonato em estação de tratamento de efluentes e rios por cromatografia líquida de alta eficiência e extração em fase sólida
The procedures to implement a chromatographic method for the quantification of linear alkyl benzene sulfonate (LAS) in the influent, effluent and sludge of a wastewater treatment plant (WWTP), and in river water and sediment, are described and evaluated. The columns octylsilane (C8) and octadecylsilane (C18) for high performance liquid chromatography were ev
Quím. Nova. Publicado em: 2017-04
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33. Composite Films from Polystyrene with Hydroxyl end Groups and Carbon Nanotubes
Composites from polystyrene with hydroxyl end groups and multiwall carbon nanotubes were fabricated to evaluate their properties. The Carbon Nanotubes (CNTs) were synthetized by chemical vapor deposition technique using ferrocene and benzene as precursors. Polystyrene with hydroxyl end groups was prepared by solution polymerization employing styrene as monom
Mat. Res.. Publicado em: 09/02/2017
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34. Effect of Capping Agent on the Morphology, Size and Optical Properties of In2O3 Nanoparticles
The Indium Oxide (In2O3) nanoparticles were synthesized through Acacia gum mediated method with the surfactants CTAB (Cetyl Trimethyl Ammonium Bromide) and SDBS (Sodium Docecyl Benzene Sulfonate). The characterization of the synthesized In2O3 nanoparticles was carried out by XRD, FTIR, RAMAN, TEM, SEM, EDAX, UV-Vis and PL techniques. TG-DTA analysis was perf
Mat. Res.. Publicado em: 09/01/2017
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35. Gallium-Containing Mesoporous Silica: Supported Catalysts with High Catalytic Activity for Oxidation of Benzene, Toluene and o-Xylene
Benzene, toluene and xylene (BTX) are a particular class of volatile organic compounds, which are highly toxic pollutants. In this study, samples of gallium-containing mesoporous silica (MS-Ga7% and MS-Ga11%) were synthesized and their catalytic activity in the oxidation of BTX was investigated. The physicochemical characterization shows that the inclusion o
J. Braz. Chem. Soc.. Publicado em: 2017-01
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36. SYNTHESIS OF CUMENE BY TRANSALKYLATION OVER MODIFIED BETA ZEOLITE: A KINETIC STUDY
Abstract In the present study, transalkylation of 1,4-diispropylbenzene (DIPB) with benzene in the presence of modified beta zeolite was performed to produce cumene in a fixed bed reactor. Beta zeolite was exchanged with cerium in order to modify its catalytic activity. Activity of the modified catalyst was evaluated in the range of temperature 493K-593K, sp
Braz. J. Chem. Eng.. Publicado em: 2016-12