Benzene
Mostrando 1-12 de 555 artigos, teses e dissertações.
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1. Novel Insecticides from Alkylated and Acylated Derivatives of Thymol and Eugenol for the Control of Plutella xylostella (Lepidoptera: Plutellidae)
Plutella xylostella cause considerable harm to the production of broccoli, Chinese cabbage, cabbage and cauliflower. The control of P. xylostella is mainly performed using commercial insecticides, which have even led to the emergence of resistant populations. Two easily available natural products found in different plants essential oil, thymol and eugenol, s
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. RING CURRENT IN ANTHRACENE AND PHENANTHRENE: CORRECTION TO HÜCKEL PARAMETERS
Excessive degeneracy in the ground state of the π-electron energy levels of anthracene was removed using the Hückel method by correcting the Coulomb integral of the four central carbon atoms. A further correction to the resonance integral was proposed based on the ring-current model, which describes the π-ring current flow along the molecule’s perimeter
Química Nova. Publicado em: 2022
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3. AN ADAPTED UNMANNED AERIAL VEHICLE FOR ENVIRONMENTAL WATER SAMPLING
In this work an unmanned aerial vehicle (UAV) was adapted to be used as an environmental tool to collect water samples of sea, estuary, and mangrove for further analysis by gas chromatography with a mass detector (GC-MS). The sampling automated system was based on a microcontroller, a solenoid valve, and a peristaltic mini-pump that was coupled to a quadcopt
Química Nova. Publicado em: 2022
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4. Capital, ideologia e uma história do mundo sob o prisma da desigualdade
The phytochemical reinvestigation from the heartwood of the extracts of Cordia glazioviana led to the isolation of four still undescribed hydroquinones derivatives designated as cordiaquinol D (1), cordiaquinol E (2), (10R)-10,11-dihydrofuran-1,4-dihydroxy-globiferin (3) and 2-[(1’E,6’E)-3’,8’- dihydroxy-3’,7’-dimethylocta-1’,6’-dienyl]-benze
Econ. soc.. Publicado em: 2021-07
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5. Anti-Inflammatory Meroterpenoids of Cordia glazioviana (Boraginaceae)
The phytochemical reinvestigation from the heartwood of the extracts of Cordia glazioviana led to the isolation of four still undescribed hydroquinones derivatives designated as cordiaquinol D (1), cordiaquinol E (2), (10R)-10,11-dihydrofuran-1,4-dihydroxy-globiferin (3) and 2-[(1’E,6’E)-3’,8’- dihydroxy-3’,7’-dimethylocta-1’,6’-dienyl]-benze
J. Braz. Chem. Soc.. Publicado em: 2021-07
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6. Liquid Phase Nitration of Benzene Catalyzed by a Novel Salt of Molybdovanadophosphoric Heteropolyacid
A highly efficient and reusable catalyst QA-HPMV was successfully prepared by the reaction of quinoline-2-formic acid (QA) with molybdovanadophosphoric heteropolyacid (H4PMo11VO40, HPMV) for the nitration of benzene. The physical and chemical properties of the sample was characterized by X-ray diffraction analysis (XRD), Fourier transform infrared spectrosco
J. Braz. Chem. Soc.. Publicado em: 2021-06
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7. A SIMPLE AND SENSITIVE LC-MS/MS METHOD FOR THE DETERMINATION OF S-PHENYLMERCAPTURIC ACID IN HUMAN URINE
Benzene is an important environmental and occupational pollutant, and recognized as human carcinogen. S-phenylmercapturic acid (SPMA) is a highly specific biomarker of exposure to benzene, applied in occupational toxicology to assess low levels of benzene exposure. The objective of this study was to develop and validate a one-step liquid extraction bioanalyt
Quím. Nova. Publicado em: 2021-03
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8. Optimization of the Reaction Conditions for the Synthesis of Dihydrobenzofuran Neolignans
We have optimized the experimental conditions for the silver(I)-promoted oxidative coupling of methyl p-coumarate (I) and methyl ferulate (II), which is the most frequently used methodology to synthesize the bioactive dihydrobenzofuran neolignans 1 ((±)-trans-dehydrodicoumarate dimethyl ester) and 2 ((±)-trans-dehydrodiferulate dimethyl ester). Most of the
J. Braz. Chem. Soc.. Publicado em: 2021-01
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9. New Insights into the Partitioning of Phenothiazine Dyes in Aqueous Two-Phase Systems
Aqueous two-phase systems (ATPSs) have proven to be efficient and environmentally safe methods for extracting chemical species. However, the driving forces behind the partition of solutes in these systems are still little understood. A complete thermodynamic partitioning of phenothiazine dyes was investigated in poly(ethylene oxide) (PEO) + salt + water ATPS
J. Braz. Chem. Soc.. Publicado em: 2020-08
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10. IMPACTOS DOS BTEX EM ÁREAS URBANAS DA CIDADE DO RIO DE JANEIRO
Most volatile organic compounds (VOC) have adverse effects on human health and the environment and react individually with different velocities and mechanisms to form ozone. The present work determined the concentration of 55 samples of benzene, toluene, ethylbenzene and xylenes (BTEX), an important subgroup of VOC, by active sampling with active carbon cart
Quím. Nova. Publicado em: 20/07/2020
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11. MEASUREMENTS AND THERMODYNAMIC MODELING OF VAPOR-LIQUID EQUILIBRIA FOR BINARY SYSTEMS OF ISOPROPYL CHLOROACETATE WITH CYCLOHEXANE, ISOPROPANOL AND BENZENE AT 101.3 kPa
Abstract In this work, the vapor-liquid equilibrium experimental data for the systems of isopropyl chloroacetate + isopropanol, isopropyl chloroacetate + cyclohexane and isopropyl chloroacetate + benzene were measured by a modified Rose-type recirculating still under the pressure of 101.3 kPa. The thermodynamic consistency of the measured data was verified
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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12. EVALUATION OF THE PHOTOCATALYTIC ACTIVITY OF SiO2@TiO2 HYBRID SPHERES IN THE DEGRADATION OF METHYLENE BLUE AND HYDROXYLATION OF BENZENE: KINETIC AND MECHANISTIC STUDY
Abstract Silica spheres coated with titania (SiO2@TiO2) were synthesized using chitosan as template. The N2 adsorption/desorption isotherms of the spheres point to meso and macroporous characteristics and the elemental mapping by EDS shows uniform distribution of Ti on the surface of the silica spheres, leading to formation of an amorphous structure (XRD). T
Braz. J. Chem. Eng.. Publicado em: 13/01/2020