3d Structure
Mostrando 13-24 de 2641 artigos, teses e dissertações.
-
13. Crystallographic Changes Accompanying the Verwey Transition in a Magnetite from Steatite
The crystallographic structural analysis of the magnetite of a steatite rock at 298 K, (saturation magnetization, σ = 95.0 J T-1 kg-1) showed two cubic networks and, below Verwey temperature (TV ca.120 K) a monoclinic structure, basing on their cell dimensions and different transitional behaviors when reducing the temperature. A monoclinic structure was ide
J. Braz. Chem. Soc.. Publicado em: 2020-09
-
14. Zinc Hexacyanoferrate/Multi-Walled Carbon Nanotubes Films for Rechargeable Aqueous Batteries
Zinc hexacyanoferrate (ZnHCF) is a Prussian Blue analog and can be intercalated by both monovalent and divalent ions. ZnHCF/multi-walled carbon nanotube (MWCNT) film could be used as a cathode for zinc ions battery. Carbon nanotubes improved significantly the electrochemical performance of the electrode. It is described the preparation of ZnHCF/MWCNT films b
J. Braz. Chem. Soc.. Publicado em: 2020-09
-
15. A Compact, Wideband, Dual Polarized CPW-Fed Asymmetric Slot Antenna for Wireless Systems
Abstract Wideband, dual sense circularly polarized (CP), asymmetric circular slot fed by coplanar waveguide is proposed and designed. Dual polarizations are obtained by using a horizontal stub to the feed line and embedding the L-shaped strip onto the slotted ground plane. The simulated result of impedance bandwidth shows wideband performance is produced by
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
-
16. ASPECTOS ESTRUTURAIS DE ESFERAS DE QUITOSANA/PVA RETICULADAS COM GLUTARALDEÍDO SUBMETIDAS A DIFERENTES TRATAMENTOS TÉRMICOS
Chitosan is a biopolymer derived from chitin and the most abundant polysaccharide in nature after cellulose. This biopolymer has been applied in different areas due its biodegradability and biocompatibility properties. Modifications of chitosan structure by cross-linking chemical agents can alter its physical, chemical, and morphological characteristics. The
Quím. Nova. Publicado em: 2020-09
-
17. Risk Factors for Mortality in Pediatric Cardiac Intensive Care Unit
The present study investigated the activity of pyrimidine derivatives against Aedes aegypti. Two compounds, 3c and 3d showed excellent larvicide activity. Additionally, quantitative structure-activity relationship (QSAR) models were built using multiple-linear regression and partial least squares with descriptors generated from Dragon and VolSurf+ software,
Int. J. Cardiovasc. Sci.. Publicado em: 2020-07
-
18. Pyrimidine Derivatives: QSAR Studies of Larvicidal Activity against Aedes aegypti
The present study investigated the activity of pyrimidine derivatives against Aedes aegypti. Two compounds, 3c and 3d showed excellent larvicide activity. Additionally, quantitative structure-activity relationship (QSAR) models were built using multiple-linear regression and partial least squares with descriptors generated from Dragon and VolSurf+ software,
J. Braz. Chem. Soc.. Publicado em: 2020-07
-
19. THEORETICAL STUDIES ON DIACETONEDIPEROXIDE DERIVATIVES AND COMPARISONS WITH OTHER MULTI-PEROXIDIC COMPOUNDS
Diacetonediperoxide (DADP) derivatives were investigated with density functional theory (DFT) methods at the DFT-B3LYP and M06-2X/6-311++G (d, p) levels and were also compared with other multi-peroxidic compounds. The investigated derivatives were 3,6-dimethyl-3,6-diamine-1,2,4,5-tetraoxane (DADPNH2), 3,6-dimethyl-3,6-dinitro-1,2,4,5-tetraoxane (DADPNO2), an
Quím. Nova. Publicado em: 2020-06
-
20. Structural and physicochemical properties of freeze-dried açaí pulp (Euterpe oleracea Mart.)
Abstract The objective of this study was to characterize the structural and physicochemical properties, the bioactive compounds and the antioxidant activity of freeze-dried açaí pulp (FDAP). The morphology of freeze-dried açaí pulp showed a continuous matrix with a spongey aspect, and the X-ray diffractometry indicated that 96.17% of the molecular struct
Food Sci. Technol. Publicado em: 2020-06
-
21. Crystal Structure and 1H NMR Experimental and Theoretical Study of Conformers of 5-Methyl-1-(4’-methylphenylsulfonylamino)-1H-[1,2,3]-triazole-4-carboxylic Acid Ethyl Ester and 5-Methyl-1-(phenylsulfonylamino)-1H-[1,2,3]-triazole-4-carboxylic Acid Ethyl Ester
We reported experimental and theoretical investigation of conformers of 1,2,3-triazole derivatives, substances of exclusively synthetic origin, subject of extensive studies, because of several biological properties, such as antiviral, antimicrobial and antileishmaniasis. We reported molecular/supramolecular X-ray structures of antiophidian compounds I and II
J. Braz. Chem. Soc.. Publicado em: 2020-05
-
22. 3-Aminofurostane Alkaloids from Solanum paniculatum (“Jurubeba Verdadeira”) Roots
The roots of Solanum paniculatum (Solanaceae) have extensively been used in folk medicine to treat liver infections and as a diuretic. Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) were used for the profiling and structural characterization of alkaloids from the roots of S. paniculatum. Six
J. Braz. Chem. Soc.. Publicado em: 2020-05
-
23. Multifractal analysis of soil fauna diversity indexes
ABSTRACT The objective of this study was to determine the multifractality of diversity indexes of edaphic fauna in areas with natural vegetation and in agricultural systems. Biological sampling was carried out in seven treatments (millet, maize, soybean, eucalyptus, preserved cerrado, disturbed cerrado and pasture), containing 130 pitfall traps, distributed
Bragantia. Publicado em: 2020-03
-
24. Experimental and Theoretical Study of LiMn2O4 Synthesized by the Solution Combustion Method Using Corn Starch as Fuel
Lithium manganese oxide, LiMn2O4, was synthesized in two temperature stages, where the first consisted by an ecofriendly solution combustion method at 300 °C. Finally, the as-burned powders were thermal treated at 500 and 700 °C. The structural and morphological changes were evaluated by the Rietveld method and density functional theory (DFT) calculations.
J. Braz. Chem. Soc.. Publicado em: 2020-02