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1.
Lucas Portela Oliveira Camila Cristina de Foggi Bruna Natália Alves da Silva Pimentel Marcelo Assis Juan Andrés Elson Longo Carlos Eduardo Vergani 《Ceramics International》2021,47(16):22604-22614
The present study reports for the first time the performance of silver phosphate (Ag3PO4) microcrystals as photocatalyst (degradation of Rodamine B-RhB) and antifungal agent (against Candida albicans–C. albicans) under visible-light irradiation (455 nm). Ag3PO4 microcrystals were synthesized by a simple co-precipitation (CP) method at room temperature. The structural and electronic properties of the as-synthetized Ag3PO4 have been investigated before and after 4 cycles of RhB degradation under visible light using X-ray diffraction (XRD), micro-Raman spectroscopy, UV–Vis spectrophotometer and field emission scanning electron microscopy (FE-SEM) images. The antifungal activity was analyzed in planktonic cells and 48h-biofilm of C. albicans by colony forming units (CFU) counting, confocal laser and FE-SE microscopies. Statistical analysis was carried out using SPSS software. Morphological and structural modifications of Ag3PO4 were observed upon recycling. After 4 recycles, the material maintained its photodegradation property; an eightfold increase in the efficiency of Ag3PO4 was observed in planktonic cells and a two fold increase in biofilm when irradiated under visible light. Thus, higher antifungal effectiveness against C. albicans was obtained when associated with visible-light irradiation. 相似文献
2.
The concentrations of arsenic, selenium, iodine and bromine in a series of fish, plant and mammalian oils have been determined
by cyclic instrumental neutron activation analysis (CINAA). Crude fish oils contain between 0.047 and 0.151 μg Se g−1, 2.36–14.5 μg As g−1, 2.36–9.63 μg Br g−1 and 0.97–4.76 μgI g−1. Seal oil contains the same four elements, but at levels below the lower end of the fish oil ranges. Iodine, bromine and
arsenic were not detected in rape-seed or soybean oils and the concentration of selenium varied from < 0.010 to 0.042 μg g−1. The levels of selenium, iodine and bromine are reduced markedly by hydrogenation of the menhaden oils. The CINAA method
yielded results which were in agreement with pub-lished values obtained by other methods. The technique was rapid, requiring
minimal sample manipulation, and was essentially free from interferences. 相似文献
3.
The power spectral density (PSD), in its two-dimensional form, has been designated as the preferred quantity for specifying surface roughness on a draft international drawing standard for surface texture. The correct calculation of the one-dimensional PSD from discrete surface profile data is given, and problems in using fast Fourier-transform routines that are given in some of the standard reference books are flagged. The method given here contains the correct normalizing factors. Two ways to reduce the variance of the PSD estimate are suggested. Examples are shown of the variance reduction possible in the PSD's. 相似文献
4.
5.
Adriel Bortolin Fauze A. Aouada Márcia R. de Moura Caue Ribeiro Elson Longo Luiz H. C. Mattoso 《应用聚合物科学杂志》2012,123(4):2291-2298
This article studied the applicability of poly(acrylamide) and methylcellulose (PAAm‐MC) hydrogels as potential delivery vehicle for the controlled‐extended release of ammonium sulfate (NH4)2SO4 and potassium phosphate (KH2PO4) fertilizers. PAAm‐MC hydrogels with different acrylamide (AAm) and MC concentrations were prepared by a free radical polymerization method. The adsorption and desorption kinetics of fertilizers were determined using conductivity measurements based on previously built analytical curve. The addition of MC in the PAAm chains increased the quantities of (NH4)2SO4 and KH2PO4 loaded and extended the time and quantities of fertilizers released. Coherently, both loading and releasing processes were strongly influenced by hydrophilic properties of hydrogels (AAm/MC mass proportion). The best sorption (124.0 mg KH2PO4/g hydrogel and 58.0 mg (NH4)2SO4/g hydrogel) and desorption (54.9 mg KH2PO4/g hydrogel and 49.5 mg (NH4)2SO4/g hydrogel) properties were observed for 6.0% AAm–1.0% MC hydrogels (AAm/MC mass proportion equal 6), indicating that these hydrogels are potentially viable to be used in controlled‐extended release of fertilizers systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
6.
Weanling rats were fed fat free diets supplemented with 10% added fatty acids so that dietary effects on bone marrow fatty acids could be determined. The addition or deletion of linoleic acid from the fatty acid supplement resulted in alterations of the fatty acid patterns of bone marrow lipids but to a lesser degree than in erythrocyte lipids. With myristic acid supplementation, increased amounts of stearic acid were found in the lipid fractions, the difference between the bone marrow and erythrocyte lipids being less marked than when linoleic acid was fed. The activities of the bone marrow lipases varied with the dietary treatment. When linoleic acid was fed, higher rates of hydrolysis were observed with saturated fatty acid substrates. The reverse occurred when saturated fatty acids were fed. 相似文献
7.
Malte Elson Johannes Breuer James D. Ivory Thorsten Quandt 《The Journal of communication》2014,64(3):521-542
Recent research has attempted to describe meaningful experiences with entertainment media that go beyond hedonic enjoyment. Most of this research focuses on noninteractive media, such as film and television. When applied to digital games, however, such research needs to account for not only the content of the medium, but also the unique dimensions of digital games that distinguish them from noninteractive media. Experiences with digital games are shaped by the game mechanics that define the users' interaction with game content, as well as by the opportunities for social interaction that many games offer. We argue that the complex interplay of these dimensions (narrative, mechanics, and context) facilitates or inhibits meaningful user experiences in ways that are unique to digital games. 相似文献
8.
9.
Electroconductive papers were produced by coating commercial base papers with blends of poly(3,4‐ethylenedioxythiophene)/poly(4‐styrenesulfonate) (PEDOT:PSS) and organic solvents. The bulk conductivities of the coated papers were measured using a four‐probe technique. One‐sided and two‐sided coating gave comparable conductivity levels. The presence of sorbitol and isopropanol in the PEDOT:PSS blends did not enhance the bulk conductivity of the coated paper, and with increasing concentrations of these solvents, the conductivity decreased due to dilution of the conducting component. Samples coated with PEDOT:PSS blends containing N‐methylpyrrolidone (NMP) or dimethyl sulfoxide (DMSO) exhibited a higher conductivity than those coated with pure PEDOT:PSS because of their plasticizing effect and conformational changes of PEDOT molecules indicated by the red shift and disappearance of the shoulder peak at about 1442 cm?1 in the Raman spectra of the coated samples. EDS imaging showed that PEDOT:PSS is distributed throughout the thickness direction of the paper. Contact angle measurements were made to monitor the hydrophilicity of the paper surface and total sulfur analysis was used to determine the amount of PEDOT:PSS deposited onto the paper. The tensile strength of all the paper samples increased slightly after treatment. Thus, it is demonstrated that enhanced bulk conductivity in the order of 10?3 S/cm can be achieved by using organic conductive materials and surface treatment techniques. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
10.
Sintering of porous alumina obtained by biotemplate fibers for low thermal conductivity applications
Tiago Delbrücke Rogério A. Gouvêa Mário L. Moreira Cristiane W. Raubach José A. Varela Elson Longo Margarete R.F. Gonçalves Sergio Cava 《Journal of the European Ceramic Society》2013,33(6):1087-1092
In this research report, a sintering process of porous ceramic materials based on Al2O3 was employed using a method where a cation precursor solution is embedded in an organic fibrous cotton matrix. For porous green bodies, the precursor solution and cotton were annealed at temperatures in the range of 100–1600 °C using scanning electron microscopy (SEM) and thermogravimetric (TG) analysis to obtain a porous body formation and disposal process containing organic fibers and precursor solution. In a structure consisting of open pores and interconnected nanometric grains, despite the low porosity of around 40% (calculated geometrically), nitrogen physisorption determined a specific surface area of 14 m2/g, which shows much sintering of porous bodies. Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analytical methods revealed a predominant amount of α-Al2O3 in the sintered samples. Thermal properties of the sintered Al2O3 fibers were obtained by using the Laser Flash which resulted in the lower thermal conductivity obtained by α-Al2O3 and therefore improved its potential use as an insulating material. 相似文献