This work reports on the characterization of new heat transfer fluids consisting in dispersions of functionalized graphene nanoplatelets (fGnP) in Havoline XLC Premixed 50/50 base fluid. Optical, ...stability and rheological properties have been considered, with the aim to assess the nano-suspension potential for volumetric direct solar absorbers. Nanoparticle addition leads to a considerably higher sunlight absorption with respect to the pure base fluid even at the investigated extremely low concentrations (0.005% and 0.05% wt). Rheology tests show a Newtonian behaviour in the shear rate range between 10 and 1000 s−1. Viscosity and thermal conductivities do not significantly increase with respect to the pure base fluid, showing that these new fluids will not require additional pumping powers to flow.
•Nanofluids consisting of functionalized graphene nanoplatelets in Havoline XLC have been prepared and characterized.•A considerable sunlight extinction is obtained in short path lengths, even at low nanoparticle loading.•Obtained dynamic viscosity shows that the fluids are Newtonian in all studied conditions.•No significant viscosity increase with nanoparticle addition was found.•Therefore pumping powers necessary to make these new fluids flow will not noticeably rise.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Abstract
The purpose of this review was to highlight the most frequent biological indicators used to estimate the microbiological quality of drinking and recreational water. It was observed that the ...incorporation of other microbiological indicators should be considered to strengthen the decision-making process on water quality management and guarantee its safe consumption in recreational activities.
This work presents experimental results on the isobaric heat capacity of ethylene glycol (EG) based nanofluids containing three types of nitride nanoparticles: aluminium nitride (AlN), silicon ...nitride (Si3N4) and titanium nitride (TiN). The densities of the nanofluids were also investigated in this study. Each type of material was used in two different sizes of nanoparticles and with various values of specific surface area. Temperature-modulated differential scanning calorimetry and vibrating tube techniques were used, and measurements were performed at three different temperatures: 288.15 K, 298.15 K and 308.15 K. The obtained experimental results were compared with the predictions of theoretical models, and absolute average deviations were calculated. It was demonstrated that the fraction of nanoparticles strongly affects isobaric heat capacity and density, while the size of the particles does not significantly impact these properties.
•Ethylene glycol based nanofluids containing various mass fractions of AlN, Si3N4, TiN nanoparticles has been investigated.•Isobaric heat capacity and density of those nanofluids has been measured at different temperatures.•A summary of experimental data and theoretical models has been presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Heat transfer enhancement of ZnO–ethylene glycol nanofluids was studied.•Nanofluids' physical properties were studied at different temperatures up to 70 °C.•2.5 wt.% ZnO nanofluids enhanced the heat ...transfer coefficient up to 30%.•Heat transfer may be deteriorated due to deposition at higher particle fractions.•Nanoparticles in different flow regimes have different effects on the pressure drop.
Transition regime convection heat transfer coefficients of zinc oxide/ethylene glycol–water (ZnO/EG-W) nanofluid in a circular pipe were investigated experimentally where the mass fraction of nanoparticles in the base fluid is from 0 to 5 wt.% and at operating temperatures. Different ZnO/EG-W mass concentration nanofluids were prepared, and the physical and thermal transport properties including density, thermal conductivity, specific heat capacity and viscosity were measured and the results were compared with the base fluid. It was found that the nanofluid has maximum of 30% higher heat transfer coefficient compared to base fluid at mass fraction of 2.5 wt.%, whereas at higher values of the nanoparticles' mass concentration of 5 wt.%, the heat transfer coefficient decreases. There is an optimal value of the concentration for the nanoparticles to have the maximal enhancement of the heat transfer. The measurements also showed that the pressure drop of nanofluid was higher than that of the base fluid in a turbulent flow regime. However, there was no significant increase in pressure drop at laminar flow. Our results demonstrated that the ZnO/EG-W nanofluid might be a promising alternative for conventional coolants.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This work contributes with experimental information of the properties of ethylene glycol-based Co3O4 nanofluids. Thermal conductivity, high-pressure density and rheological characterization were ...performed in the temperature range T=(283.15–323.15)K. Thermal conductivity and rheological behaviour were studied for nanofluid samples with concentrations of Co3O4 nanoparticles up to 25% in weight fraction whereas the densities of the nanofluid were analysed up to 5% at pressures up to 45MPa. Thermal conductivity showed in the range studied an increase with weight fraction and a decrease with temperature. A volumetric contractive behaviour was observed, and an increment in the nanoparticles concentration leads to a clear departure from ideal behaviour. The tests performed to analyse rheological properties showed that the viscosity of the nanofluids is nearly independent of the shear rate, thus evidencing the characteristic behaviour of a Newtonian fluid. Experimental viscosity and thermal conductivity were also compared with the estimations provided by several semiempirical equations proposed in the literature.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The dispersion and stability of nanofluids obtained by dispersing Al
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nanoparticles in ethylene glycol have been analyzed at several concentrations up to 25% in mass fraction. The thermal ...conductivity and viscosity were experimentally determined at temperatures ranging from 283.15 K to 323.15 K using an apparatus based on the hot-wire method and a rotational viscometer, respectively. It has been found that both thermal conductivity and viscosity increase with the concentration of nanoparticles, whereas when the temperature increases the viscosity diminishes and the thermal conductivity rises. Measured enhancements on thermal conductivity (up to 19%) compare well with literature values when available. New viscosity experimental data yield values more than twice larger than the base fluid. The influence of particle size on viscosity has been also studied, finding large differences that must be taken into account for any practical application. These experimental results were compared with some theoretical models, as those of Maxwell-Hamilton and Crosser for thermal conductivity and Krieger and Dougherty for viscosity.
Equex STM paste, a water‐soluble detergent, exerts the protective effect of egg‐yolk during sperm cryopreservation. This study aims to evaluate the post‐thaw quality of rhesus monkeys’ epididymal ...spermatozoa in the Tris–citric–glucose egg‐yolk extender, supplemented with or without Equex STM paste (0.5%, v/v) (n = 6). Sperm motility, progressive motility, motion characteristics, viability, acrosome integrity and mitochondrial activity were compared immediately post‐thaw. Equex STM paste supplementation significantly improved sperm motility (35.0 ± 4.5 vs. 23.7 ± 5.0%), progressive motility (15.4 ± 2.1 vs. 9.8 ± 2.7%) and percentage of sperm with intact acrosome (30.4 ± 4.5 vs. 26.3 ± 4.6%) compared to the controls, respectively. This is the first report applying Equex STM paste for monkey epididymal sperm cryopreservation and is expected to be beneficial as a model for endangered non‐human primates.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Antigenic diversity has posed a critical barrier to vaccine development against the pathogenic blood-stage infection of the human malaria parasite Plasmodium falciparum. To date, only strain-specific ...protection has been reported by trials of such vaccines in nonhuman primates. We recently showed that P. falciparum reticulocyte binding protein homolog 5 (PfRH5), a merozoite adhesin required for erythrocyte invasion, is highly susceptible to vaccine-inducible strain-transcending parasite-neutralizing antibody. In vivo efficacy of PfRH5-based vaccines has not previously been evaluated. Here, we demonstrate that PfRH5-based vaccines can protect Aotus monkeys against a virulent vaccine-heterologous P. falciparum challenge and show that such protection can be achieved by a human-compatible vaccine formulation. Protection was associated with anti-PfRH5 antibody concentration and in vitro parasite-neutralizing activity, supporting the use of this in vitro assay to predict the in vivo efficacy of future vaccine candidates. These data suggest that PfRH5-based vaccines have potential to achieve strain-transcending efficacy in humans.
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•Vaccines based on the P. falciparum merozoite antigen PfRH5 were tested in Aotus monkeys•PfRH5-based vaccines afforded protection against heterologous strains of P. falciparum•Protection correlated with anti-PfRH5 IgG concentration and in vivo neutralization
Antigenic diversity has hindered development of vaccines against the pathogenic blood-stage of Plasmodium falciparum. Douglas et al. demonstrate that human-compatible PfRH5-based vaccines can protect Aotus monkeys against vaccine-heterologous P. falciparum challenge. Protection correlated with anti-PfRH5 antibody concentration and parasite-neutralizing activity. PfRH5-based vaccines have potential to achieve strain-transcending efficacy in humans.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The identification of bacteria plays an essential role in multiple areas of research. Those areas include experimental biology, food and water industries, pathology, microbiology, and evolutionary ...studies. Although there exist methodologies for identification, a transition to a whole-genome sequence-based taxonomy is already undergoing. Next-Generation Sequencing helps the transition by producing DNA sequence data efficiently. However, the rate of DNA sequence data generation and the high dimensionality of such data need faster computer methodologies. Machine learning, an area of artificial intelligence, has the ability to analyze high dimensional data in a systematic, fast, and efficient way. Therefore, we propose a sequential deep learning model for bacteria identification. The proposed neural network exploits the vast amounts of information generated by Next-Generation Sequencing, in order to extract an identification model for whole-genome bacteria sequences. After validating the identification model, the bidirectional recurrent neural network outperformed other classification approaches.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
In this experimental study, several alumina Nanoparticle Enhanced Ionic Liquids were prepared and studied in regard to their stability, pH, density and thermal conductivity. These new fluids were ...manufactured by dispersing aluminium oxide nanoparticles in different mixtures based on water and 1-ethyl-3-methylimidazolium methanesulfonate ionic liquid. Furthermore, thermophysical properties (density, thermal conductivity) of pure and binary mixtures with water and 1-ethyl-3-methylimidazolium methanesulfonate were studied in order to select and propose base fluids to design new advanced heat transfer fluids. The pH of the dispersions was determined as around 8.0–8.5. In regard to density, the overall C2mimCH3SO3 density is higher by 25% than that of water and the influence of ionic liquid density over the mixtures was found to be much higher than that of water, while for the alumina Nanoparticle Enhanced Ionic Liquids the density respects classical equations. Evaluation of thermal conductivity revealed an increase of up to 13% in thermal conductivity when nanoparticles are added to the base fluids and new correlations based on mass fraction and temperature were proposed.
•Ionic liquid-water mixtures were prepared.•pH of developed new fluids is measured and good stability is noticed.•Al2O3 NEIL density is experimentally examined and good agreement with existing equations was noticed.•Al2O3 NEIL thermal conductivity is experimentally examined and an enhancement was noted.•Al2O3 NEIL thermal conductivity correlations are proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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