This work deals with the preparation of novel photocatalysts based on the assembly of ZnO nanoparticles on the surface of sepiolite (Sep) fibrous clay mineral, which can be previously modified by ...treatment with cetyltrimethylammonium bromide, tetramethoxyortosilicate or magnetite (Fe3O4) nanoparticles. The structural and morphological features of the prepared samples were characterized by diverse experimental techniques. The photoactivity of the resulting materials has been tested under solar light irradiation for the degradation of emerging pollutants, such as ibuprofen, acetaminophen and antipyrine. The resulting ZnO/Sep heterostructure exhibits enhanced photocatalytic performance compared to ZnO/SiO2-Sep and ZnO/Fe3O4-Sep materials. Ibuprofen showed higher degradation rates than the other target compounds. Of particular interest is the use of ZnO/Fe3O4-Sep photocatalyst, which shows the simultaneous features of superparamagnetic character and photocatalytic activity, allowing its easy recovery by application of an external magnetic field which improves its reusability.
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•Heterostructured materials based on the assembly of ZnO nanoparticles to sepiolite nanofibers•Heterogeneous photocatalysts for decomposition of pollutants in water•Degradation of emerging pollutants (ibuprofen, acetaminophen and antipyrine drugs) under solar light irradiation
Research which concerns the usefulness of Probiotics show increasing interest based on the rise of their publications, products and the awareness of the public of their benefits. There is increasing ...interest concerning Probiotics from the public, researchers, governmental organizations (such as the WHO/FAO) and medicinal and food companies. Probiotics means “let good microbes work for you in different fields get their benefits and take a rest”. Such work will include, food digestion, production of useful products to destroy the bad microbes, complement the functions of the missed digestive enzymes (due to missed or defective genes), and to maintain the digestive system’s pH, and so on. Probiotics will augment the efficiency of our biological fermentors, the digestive system. Many authors have described the history and the progress of Probiotics and their different applications. In this review, we will focus mainly on three points, health improvement, infection control and disease management, which could be eliminated by the use of different types of direct uses of Probiotics or by the use of foods containing Probiotics.
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•Use of sepiolite fibrous clay as a nano-platform for simultaneous assembly of ZnO and magnetite nanoparticles.•ZnO/Fe3O4-sepiolite materials exhibiting photoactivity and ...superparamagnetic properties.•Heterogeneous photocatalysts for decomposition of pollutants in water showing easy recovery by means of a magnet.
Novel ternary ZnO/Fe3O4-sepiolite nanostructured materials were developed in a two-step procedure based on the incorporation of ZnO nanoparticles on a substrate composed by magnetite nanoparticles previously assembled to the sepiolite fibrous silicate (Fe3O4-sepiolite). The structural and morphological characterization shows that both, ZnO and Fe3O4 nanoparticles, were homogeneously dispersed on the surface of sepiolite. Therefore, the resulting material is characterized as a multifunctional nanoplatform simultaneously providing magnetic and photoactive properties. ZnO/Fe3O4-sepiolite materials exhibit superparamagnetic properties at room temperature, which is one of the sought properties in view to facilitate their recovery from the reaction medium after application as heterogeneous catalysts. ZnO/Fe3O4-sepiolite materials were tested as photocatalysts using methylene blue dye in water as model of a pollutant molecule, showing full decolorization after 2h of UV irradiation. Moreover, the photocatalytic activity of this nanoplataform may be maintained after reuse in several consecutive cycles of treatment. Remarkably, the ZnO/magnetite-sepiolite nanostructured material displays a similar activity as ZnO/sepiolite materials, but shows the additional advantage of easier recovery by means of a magnet which facilitates its reuse.
In this work, ZnO-clay heterostructured materials have been prepared as novel nanoarchitectures by generation of ZnO nanoparticles (NP) on the surface of the clay mineral. The synthetic approach ...implies previous modification of the clay minerals by cation exchange with cetyltrimethylammonium bromide (CTAB) solutions. So, these organophilic solids can be easily dispersed in 2-propanol being further incorporated ZnO nanoparticles (NP), which in turn are formed from reaction of zinc acetate with KOH solution. Once this sol–gel reaction is achieved, the intermediate ZnO/clay organo-heterostructures can be submitted to a thermal treatment for the removal of the organic matter, which finally gives rise to the ZnO/clay nanoarchitectures. The resulting materials were characterized by XRD, FE-SEM, TEM, UV–vis, FTIR, TG and DTA, specific surface area and porosity determinations. These techniques clearly shown the structural and textural arrangements produced during the formation of the ZnO/clay nanoarchitectures. This novel type of materials act as efficient heterogeneous photocatalysts showing higher yield in the photocatalytic decomposition of methylene blue (MB) dye in water than the corresponding ZnO powder without clay prepared under similar experimental conditions.
•Assembly of ZnO nanoparticles to organoclays based on smectites and sepiolite•Novel methodology for the easy preparation of porous ZnO-clay nanoarchitectures•Heterogeneous photocatalysts for decomposition of pollutants in water
Aims.Ground-based observations at thermal infrared wavelengths suffer from large background radiation due to the sky, telescope and warm surfaces in the instrument. This significantly limits the ...sensitivity of ground-based observations at wavelengths longer than ~3 μm. The main purpose of this work is to analyse this background emission in infrared high-contrast imaging data as illustrative of the problem, show how it can be modelled and subtracted and demonstrate that it can improve the detection of faint sources, such as exoplanets. Methods. We used principal component analysis (PCA) to model and subtract the thermal background emission in three archival high-contrast angular differential imaging datasets in the M′ and L′ filter. We used an M′ dataset of β Pic to describe in detail how the algorithm works and explain how it can be applied. The results of the background subtraction are compared to the results from a conventional mean background subtraction scheme applied to the same dataset. Finally, both methods for background subtraction are compared by performing complete data reductions. We analysed the results from the M′ dataset of HD 100546 only qualitatively. For the M′ band dataset of β Pic and the L′ band dataset of HD 169142, which was obtained with an angular groove phase mask vortex vector coronagraph, we also calculated and analysed the achieved signal-to-noise ratio (S/N). Results. We show that applying PCA is an effective way to remove spatially and temporarily varying thermal background emission down to close to the background limit. The procedure also proves to be very successful at reconstructing the background that is hidden behind the point spread function. In the complete data reductions, we find at least qualitative improvements for HD 100546 and HD 169142, however, we fail to find a significant increase in S/N of β Pic b. We discuss these findings and argue that in particular datasets with strongly varying observing conditions or infrequently sampled sky background will benefit from the new approach.
It is expected that the world population will reach 9 billion by 2050. Thus, meat, dairy or plant-based protein sources will fail to meet global demand. New solutions must be offered to find ...innovative and alternative protein sources. As a natural gift, edible wild mushrooms growing in the wet and shadow places and can be picked by hand have been used as a food. From searching mushrooms in the forests and producing single cell proteins (SCP) in small scales to mega production, academia, United Nations Organizations, industries, political makers and others, play significant roles. Fermented traditional foods have also been reinvestigated. For example, kefir, miso, and tempeh, are an excellent source for fungal isolates for protein production. Fungi have unique criteria of consuming various inexpensive wastes as sources of carbon and energy for producing biomass, protein concentrate or amino acids with a minimal requirement of other environmental resources (e.g., light and water). Fungal fermented foods and SCP are consumed either intentionally or unintentionally in our daily meals and have many applications in food and feed industries. This review addresses fungi as an alternative source of edible proteins and animal feed, focusing mainly on SCP, edible mushrooms, fungal fermented foods, and the safety of their consumption.
A highly accurate and precise HPLC-UV method was developed for identification and quantification of gemcitabine anti-cancer drug in rat plasma. A new magnetic graphene oxide-based calixarene ...composite was developed and used as a solid phase for extraction of gemcitabine from rat plasma. Extraction efficiency has been studied by varying different experimental variables (eluent type, sorbent amount, extraction time and eluent volume etc.) and these were evaluated and optimized. Magnetic solid phase extraction (MSPE) conditions such as amount of solid phase, extraction solvents and their amounts, and adsorption and desorption times were optimized for getting better recoveries. Under the optimized conditions, linearity was evaluated with good correlation coefficient value R
2
(0.9993). Limit of detection (2.0 ng/mL) and limit of quantification (13.0 ng/mL) was assessed using signal-to-noise ratio method. Intraday precision RSD values of gemcitabine (GEM) were found to be less than 4.6% and interday precision values are less than 6.8%. The results obtained during the robustness study were RSD values between 1.2 and 4.6%; these results indicate that the method has effective performance and reliability. The recovery percentages of gemcitabine at three QC level concentrations were obtained in the range from 97.6 to 100.2%.
This work deals with the preparation of novel photocatalysts based on the assembly of ZnO nanoparticles on the surface of sepiolite (Sep) fibrous clay mineral, which can be previously modified by ...treatment with cetyltrimethylammonium bromide, tetramethoxyortosilicate or magnetite (Fe3O4) nanoparticles. The structural and morphological features of the prepared samples were characterized by diverse experimental techniques. The photoactivity of the resulting materials has been tested under solar light irradiation for the degradation of emerging pollutants, such as ibuprofen, acetaminophen and antipyrine. The resulting ZnO/Sep heterostructure exhibits enhanced photocatalytic performance compared to ZnO/SiO2-Sep and ZnO/Fe3O4-Sep materials. Ibuprofen showed higher degradation rates than the other target compounds. Of particular interest is the use of ZnO/Fe3O4-Sep photocatalyst, which shows the simultaneous features of superparamagnetic character and photocatalytic activity, allowing its easy recovery by application of an external magnetic field which improves its reusability.
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•Heterostructured materials based on the assembly of ZnO nanoparticles to sepiolite nanofibers.•Heterogeneous photocatalysts for decomposition of pollutants in water.•Degradation of emerging pollutants (ibuprofen, acetaminophen and antipyrine drugs) under solar light irradiation.
This overview paper describes the legacy prospect and discovery potential of the Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from the DES early data. DES is ...using a wide-field camera (DECam) on the 4 m Blanco Telescope in Chile to image 5000 sq deg of the sky in five filters (grizY). By its completion, the survey is expected to have generated a catalogue of 300 million galaxies with photometric redshifts and 100 million stars. In addition, a time-domain survey search over 27 sq deg is expected to yield a sample of thousands of Type Ia supernovae and other transients. The main goals of DES are to characterize dark energy and dark matter, and to test alternative models of gravity; these goals will be pursued by studying large-scale structure, cluster counts, weak gravitational lensing and Type Ia supernovae. However, DES also provides a rich data set which allows us to study many other aspects of astrophysics. In this paper, we focus on additional science with DES, emphasizing areas where the survey makes a difference with respect to other current surveys. The paper illustrates, using early data (from ‘Science Verification’, and from the first, second and third seasons of observations), what DES can tell us about the Solar system, the Milky Way, galaxy evolution, quasars and other topics. In addition, we show that if the cosmological model is assumed to be Λ+cold dark matter, then important astrophysics can be deduced from the primary DES probes. Highlights from DES early data include the discovery of 34 trans-Neptunian objects, 17 dwarf satellites of the Milky Way, one published z > 6 quasar (and more confirmed) and two published superluminous supernovae (and more confirmed).
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