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151.
152.
Lopes EC dos Anjos FS Vieira EF Cestari AR 《Journal of colloid and interface science》2003,263(2):542-547
In this work, thin chitosan membranes were utilized as an adsorbent for the removal of Hg(II) from aqueous solutions. A rise of temperature accelerates the mass transfer of Hg(II) to the membranes, surfaces. The kinetic data did not present a good fitting to the traditional Lagergren adsorption kinetic equations. An alternative Avrami kinetic equation was employed and successfully fitted to the kinetic adsorption quantities. From this new equation, two regions presenting distinct kinectic parameters were found, and the use of the parameter n was also relationed to the determination of the kinetic order. Variations of the adsorption kinetic rate in relation to the time, the initial Hg(II) concentration, and the temperature were also calculated and are discussed. 相似文献
153.
Camila Cristina Iwanaga Lilian dos Anjos Oliveira Ferreira Karine Zanoli Bernuci Carla Maria Mariano Fernandez Fabiana Brusco Lorenzetti Camila Caviquioli Sehaber 《Natural product research》2019,33(11):1655-1658
The present study investigated the in vitro and in vivo antioxidant potential and phytochemical composition of Schinus terebinthifolia, which is widely used in folk medicine for various therapeutic purposes. The in vitro analyses indicated that the hydroethanolic extract (HE) had 312.50 ± 0.50 mg GAE/g of total phenols. It also presented anti-DPPH? and anti-ABTS?+ activity, reduced phosphomolybden and metal ions and blocked the bleaching of β-carotene. The HE at concentrations of 3.0 and 2.0 μg/mL had TRAP values of 2.223 ± 0.018 and 1.894 ± 0.026 μM Trolox, respectively. The HE increased the availability of antioxidants in plasma in treated animals in vivo. HPLC-ESI-MS/MS indicated the presence of 11 phenols: cumaric acid, (+)-catechin, myricetin-3-O-glicuronide, kaempferol-3-O-glucoside, myricetin, myricitrin, quercetin, gallic acid, methyl galate, pentagalloyl glucose and ethyl galate. Thus, S. terebinthifolia has potential for the prevention or treatment of diseases that are related to oxidative stress, such as diabetes mellitus. 相似文献
154.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Duboscq JE Elliott JR Escobar CO Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Ong P Pinfold J Punkar G Purohit MV Santoro AF Schmidt DM Sidhu JS Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review letters》1990,65(21):2630-2633
155.
Shashwati Sen DK Aswal Ajay Singh TV Chandrasekhar Rao KP Muthe JC Vyas LC Gupta SK Gupta VC Sahni 《Pramana》2002,58(5-6):867-870
The MgB2 superconductor, synthesized using solid-state and liquid-phase sintering methods, have been characterized for various properties.
The upper critical field, irreversibility line and critical current density have been determined using magnetization data.
The current-voltage characteristics recorded under an applied magnetic field revealed the existence of vortex glass transition.
The surface analysis using X-ray photoelectron spectroscopy shows that MgB2 is sensitive to atmospheric degradation. 相似文献
156.
Fluxes of cosmic rays: a delicately balanced stationary state 总被引:1,自引:0,他引:1
The analysis of cosmic rays fluxes as a function of energy reveals a knee slightly below 1016 eV and an ankle close to 1019 eV. Their physical origins remain up to now quite enigmatic; in particular, no elementary process is known which occurs at energies close to 1016 eV. We propose a phenomenological approach along the lines of nonextensive statistical mechanics, a formalism which contains Boltzmann–Gibbs statistical mechanics as a particular case. The knee then appears as a crossover between two fractal-like thermal regimes, the crossover being caused by process occurring at energies ten million times lower than that of the knee, in the region of the quark hadron transition (109 eV). This opens the door to an unexpected standpoint for further clarifying the phenomenon. 相似文献
157.
Thiago O. Mendes Georgia M. A. Junqueira Brenda L. S. Porto Charles D. Brito Fernando Sato Marcone A. L. de Oliveira Virgilio Anjos Maria J. V. Bell 《Journal of Raman spectroscopy : JRS》2016,47(6):692-698
This paper presents a systematic analysis of the infrared absorption spectra and Raman scattering of the triacylglycerol molecule predominant in raw bovine milk. Gas chromatography measurements were also performed and revealed the palmitic, stearic, and oleic acids as the most predominant fatty acids in the composition of milk. Based on the gas chromatography results, infrared, and Raman spectra of the triacylglycerol with this combination of fatty acids were simulated. The theoretical spectra were compared with the experimental ones of milk fat and fluid raw milk. Assignment of bands of milk fat was proposed, which can be used for a quality monitoring of the product. We also performed a multivariate model of partial least squares from samples of fluid milk with different concentrations of fat. As a result, the most important variables in the projection were selected as vibrational markers for quality monitoring and quantifying of this important constituent of milk. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
158.
We describe the main features of a numerical simulator currently under development for studying water physico-chemical properties during the flooding of hydroelectric plants reservoirs. The work is sponsored by the brazilian Electric Energy National Agency ANEEL and conducted in a joint work of brazilian universities rearchers, with Furnas Centrais Elétricas S. A., the leading brazilian power utility company. An overview of the simulator requirements and of the involved partners is given. The software modules and engineering solutions are briefly discussed, including the finite element based transport module. Some results, future steps and partnerships are presented and discussed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
159.
The cross section for backward elastic pd scattering in the proton kinetic energy interval from 0.4 to 1.0 GeV is calculated from a double-triangle diagram with intermediate Δ(1232) excitation. Different approximations for the loop integrals are discussed. The predicted cross sections reproduce quite well the enhancement observed in the experimental data at about 600 MeV. 相似文献
160.
Park HS Blewitt G Cortez BG Foster GW Gajewski W Haines TJ Kielczewska D LoSecco JM Bionta RM Bratton CB Casper D Chrysicopoulou P Claus R Errede S Ganezer KS Goldhaber M Jones TW Kropp WR Learned JG Lehmann E Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak LR Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,54(1):22-25