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•The We-Re maps are plotted for various nanoparticle concentrations.•Nanofluids promote splashing for low Re numbers.•Increased lamella spreading velocity due to nanoparticles leads ...to splashing.•A generalized splashing threshold correlation incorporating the particle concentration is proposed and verified.
Even a small fraction of nanoparticles in fluids affects the splashing behavior of a droplet upon impact on a smooth surface.
Nanofluid drop impact onto a smooth sapphire substrate is experimentally investigated over wide ranges of Reynolds (102<Re<104) and Weber (50<We<500) numbers for three nanofluid mass concentrations (0.01%, 0.1%, 1%) using high-speed photography. Nanofluids are prepared by diluting a commercial Al2O3-water nanofluid in aqueous glycerol solutions without dispersants. In total, 30 samples are prepared and 1799 data points are acquired. Every sample is experimentally characterized prior to droplet impact measurements in terms of stability, density, viscosity, and surface tension to demonstrate the observed outcomes on the We-Re maps. Each droplet impact condition is repeated at least 3 times to ensure good repeatability.
The non-monotonic behavior of the spreading-to-splashing transition remains the same for nanofluids. However, nanofluids influence this boundary by promoting splashing at low Reynolds numbers. We explain this behavior by increased lamella spreading speed and lift during the lamella spreading stage. Finally, we develop an empirical correlation which describes the splashing threshold dependency on nanoparticle concentration for the first time.
The purpose of this study was to determine the effects of pH, ion type (salt and metal cations), ionic strength, cation valence, hydrated ionic radius, and solid concentration on the zeta potential ...of kaolinite and quartz powder in the presence of NaCl, KCl, CaCl
2
, CuCl
2
, BaCl
2
, and AlCl
3
solutions. The kaolinite and quartz powder have no isoelectric point (iep
)
within the entire pH range (3 < pH < 11). In the presence of hydrolysable metal ions, kaolinite and quartz powder have two ieps. As the cationic valence increases, the zeta potential of kaolinite and quartz powder becomes less negative. Monovalent cation, K
+
, yields more negative zeta potential values than the divalent cation Ba
2+
. As concentration of solid increases, the zeta potential of the minerals becomes more positive under acidic conditions; however, under alkaline conditions as solid concentration increases the zeta potential becomes more negative. Hydrated ionic radius also affects the zeta potential; the larger the ion, the thicker the layer and the more negative zeta potential for both kaolinite and quartz powder.
Since the 1970s, resistance to antimicrobial agents has become an escalating problem. In the last 25 years, treatment of infections caused by Gram-positive bacteria has been more problematical than ...ever, with infections being caused by multidrug-resistant organisms, particularly methicillin-resistant staphylococci, penicillin- and erythromycin-resistant pneumococci, and vancomycin-resistant enterococci. There is a continuing effort in the pharmaceutical industry to develop new antimicrobial agents for the treatment of resistant infections. Linezolid, quinupristin–dalfopristin, daptomycin, tigecyline, new glycopeptides and ceftobiprole are the main agents recently introduced or under clinical development. This review summarises their major properties, the results of recent studies with these agents, and future treatment possibilities.
With the increasing interest in improving high-performance cooling systems, research on droplet cooling requires more complex methods for enhancing heat transfer. Hence, we investigate the effect of ...nanoparticle presence and concentration on droplet spreading dynamics and heat transfer during the early stages of spreading on a heated surface. For this purpose, water and three water-based TiO2 nanofluid droplets (0.2, 0.5, and 1 wt%) are tested at four release heights impinging on a sapphire substrate below boiling point (80 °C). With an emissive TiAlN coating in the infrared (IR) domain, the surface temperature of the substrate is measured via a high-speed IR thermal camera. Droplet spreading is simultaneously monitored with two high-speed black/white cameras. The thermal and rheological properties are experimentally characterized for accurate results and to investigate only the nanoparticle presence in the fluid. The captured temperature fields are analyzed by solving the inverse heat conduction problem. We observe that all nanofluid droplets spread on a heated surface marginally less than water droplets. To the best of the authors’ knowledge, this study is the first to reveal that during the early stages of droplet spreading, the presence of nanoparticles and the resulting change in viscosity primarily influence heat transfer through the modification of the droplet spreading diameter, rather than changes in thermal properties.
•Heat transfer during nanofluid droplet spreading is monitored via high-speed cameras.•Nanoparticles affect heat transfer via droplet spreading during early-stage cooling.•Nanofluid droplets fall with a smaller mass due to lowered surface tension.•Spreading alteration is a result of combined effect of viscosity and surface tension.
Image‐Based Rendering allows users to easily capture a scene using a single camera and then navigate freely with realistic results. However, the resulting renderings are completely static, and ...dynamic effects – such as fire, waterfalls or small waves – cannot be reproduced. We tackle the challenging problem of enabling free‐viewpoint navigation including such stationary dynamic effects, but still maintaining the simplicity of casual capture. Using a single camera – instead of previous complex synchronized multi‐camera setups – means that we have unsynchronized videos of the dynamic effect from multiple views, making it hard to blend them when synthesizing novel views. We present a solution that allows smooth free‐viewpoint video‐based rendering (VBR) of such scenes using temporal Laplacian pyramid decomposition video, enabling spatio‐temporal blending. For effects such as fire and waterfalls, that are semi‐transparent and occupy 3D space, we first estimate their spatial volume. This allows us to create per‐video geometries and alpha‐matte videos that we can blend using our frequency‐dependent method. We also extend Laplacian blending to the temporal dimension to remove additional temporal seams. We show results on scenes containing fire, waterfalls or rippling waves at the seaside, bringing these scenes to life.
The time variations of the water temperatures at the midpoint of the heat storage tank and at the outlet of the collector in a conventional open-loop passive solar water-heating system combined with ...sodium thiosulfate pentahydrate-phase change material (PCM) were experimentally investigated during November and then enhancement of solar thermal energy storage performance of the system by comparing with those of conventional system including no PCM was observed. It was observed that the water temperature at the midpoint of the storage tank decreased regularly by day until the phase-change temperature of PCM after the intensity of solar radiation decreased and then it was a constant value of 45
°C in a time period of approximately 10
h during the night until the sun shines because no hot water is used. Heat storage performances of the same solar water-heating system combined with the other salt hydrates-PCMs such as zinc nitrate hexahydrate, disodium hydrogen phosphate dodecahydrate, calcium chloride hexahydrate and sodium sulfate decahydrate (Glauber's salt) were examined theoretically by using meteorological data and thermophysical properties of PCMs with some assumptions. It was obtained that the storage time of hot water, the produced hot water mass and total heat accumulated in the solar water-heating system having the heat storage tank combined with PCM were approximately 2.59–3.45 times of that in the conventional solar water-heating system. It was also found that the hydrated salts of the highest solar thermal energy storage performance in PCMs used in theoretical investigation were disodium hydrogen phosphate dodecahydrate and sodium sulfate decahydrate.
This study is an investigation into the meat quality parameters of Karayaka lambs at different slaughter weights (SWs). The single-born Karayaka male lambs (n=30) selected for this study were an ...average live-weight of 20 kg and weaned at 2.5-3 months of age. The animals with pre-specified SWs were divided into slaughter weight (SW) groups (30, 35, 40, 45 and 50 kg) using a fully randomized design. To determine the M. longissimus dorsi et thoracis (LD) muscle meat quality characteristics, six lambs from each weight group were slaughtered. Results revealed significant differences among the slaughter groups with regard to pH, color parameters (L*-lightness, a* redness, b* yellowness), cooking loss (CL), drip loss (DL), moisture (M), crude protein (CP) and intramuscular fat (IF) ratios. Increasing water holding capacities (WHCs) and hardness values were observed with increasing SW. Significant differences were also observed among the slaughter groups with regard to total monounsaturated fatty acid + total polyunsaturated fatty acid/total saturated fatty acid ratios and total cholesterol content. --Keywords: Karayaka sheep, fatty acid composition, lambs, meat quality, slaughter weight--
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•Technological diversification is associated with more opportunity discovery•Low technological proximity and diversification is associated with the lowest performance in terms of licenses generating ...income•High technological proximity and low diversification is associated with the low numbeers of licenses generating income•High technological proximity and diversification is associated with more opportunity discovery but also more spillover•Low technological proximity and high technological diversification is associated with the best performance in temrs of licenses generating income
The effect of diversification versus specialisation, as well as the technological proximity of R&D partners have been at the heart of innovation studies. Articles in this field either take a regional or company point of view. During the last few decades, studies on the relatedness of knowledge and its importance for innovation and commercialisation have pushed policy makers towards clustering strategies such as smart specialisation in the EU and the Innovation Supercluster Initiative in Canada. Interestingly, universities as the source of new knowledge and technologies have been absent from this literature as the focal point. This paper aims at filling one of the missing links between the literature on technological relatedness and university research commercialisation. We use patent and licence data from the USPTO and the AUTM survey to study the effect of patent portfolio composition on university research commercialisation. We use Shannon’s entropy index to differentiate between the effects of related and unrelated diversification on the number of licences generating income. Our results show a positive association of related diversification with the number of licences, but none for unrelated diversification. Furthermore, technological proximity follows an inverted-U shaped association with the number of licences generating income. However, the effect is observed only for smaller universities. We conclude that the curvilinear association is the result of cognitive distance and the absence of boundary spanners. Our findings indicate that regional policy makers intending to use universities as an engine for innovation and regional economic growth should consider policies and initiatives aimed at bridging the cognitive gap between university and industry by either increasing technological proximity or reducing cognitive distances by financing boundary spanning organisations.
The aim of this study was to determine the independent risk factors, morbidity, and mortality of central nervous system (CNS) infections caused by
Listeria monocytogenes
. We retrospectively ...evaluated 100 episodes of neuroinvasive listeriosis in a multinational study in 21 tertiary care hospitals of Turkey, France, and Italy from 1990 to 2014. The mean age of the patients was 57 years (range, 19–92 years), and 64% were males. The all-cause immunosuppression rate was 54 % (54/100). Forty-nine (49 %) patients were referred to a hospital because of the classical triad of symptoms (fever, nuchal rigidity, and altered level of consciousness). Rhombencephalitis was detected radiologically in 9 (9 %) cases. Twenty-seven (64 %) of the patients who had cranial magnetic resonance imaging (MRI) performed had findings of meningeal and parenchymal involvement. The mean delay in the initiation of specific treatment was 6.8 ± 7 days. Empiric treatment was appropriate in 52 (52 %) patients. The mortality rate was 25 %, while neurologic sequelae occurred in 13 % of the patients. In the multivariate analysis, delay in treatment odds ratio (OR), 1.07 95 % confidence interval (CI), 1.01–1.16 and seizures (OR, 3.41 95 % CI, 1.05–11.09) were significantly associated with mortality. Independent risk factors for neurologic sequelae were delay in treatment (OR, 1.07 95 % CI, 1.006–1.367) and presence of bacteremia (OR, 45.2 95 % CI, 2.73–748.1). Delay in the initiation of treatment of neuroinvasive listeriosis was a poor risk factor for unfavorable outcomes. Bacteremia was one of the independent risk factors for morbidity, while the presence of seizures predicted worse prognosis. Moreover, the addition of aminoglycosides to ampicillin monotherapy did not improve patients’ prognosis.
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