Lubrication performance of an ammonium cation-based ionic liquid used as an additive in a polar oil.

This paper studies the tribological behavior of the ionic liquid methyltrioctylammonium bis(trifluoromethylsulfonyl)imide ([N 1888 ][NTf 2 ]) as additive at different concentrations (1.25, 2.50, 3.75 and 5.00 wt%) in a polar base oil (diester). A tribometer using a ball-on-disk reciprocating configuration under fully flooded lubrication was used at a frequency of 15 Hz, at three different loads (40, 80 and 120 N), stroke length of 4 mm, and duration of 45 min. Worn surface on the disk was studied by confocal microscopy, SEM and XPS. Main results showed similar coefficient of friction for all lubricant samples; but different wear results were found at different loads, probably related with the chemical states found for fluorine on the worn surface and the temperature-dependent adsorption-desorption processes

Wetting Properties of Seven Phosphonium Cation-Based Ionic Liquids

This paper studies the wetting properties of seven phosphonium cation-based ionic liquids: trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate [P66614][(iC8)2PO2], trihexyltetradecylphosphonium bis(2-ethylhexyl)phosphate [P66614][BEHP], trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl) imide [P66614][NTf2], tributyltetradecylphosphonium dodecylbenzenesulfonate [P44414][DBS], tributylethylphosphonium diethylphosphate [P4442][DEP], trihexyltetradecylphosphonium dicyanamide [P66614][DCA], and trihexyltetradecylphosphonium chloride [P66614][Cl]. The surface tension was analyzed using the Gibbs free energy in a temperature range of 293-353 K, obtaining the expected linear decrease with temperature rise. The contact angle was measured on four different surfaces (AISI 52100 steel, CrN, TiN, and ZrN) and all liquids with high surface tensions interacting with hydrophobic systems displayed high contact angles as expected. The polarity fraction (PF) and the spreading parameter (SP) were estimated to complete and improve the wetting characterization of these ionic liquids, finding TiN-[P66614][BEHP] and TiN-[P66614][(iC8)2PO2] as the most favorable surface-ionic liquid combinations from a wetting point of view

Physicochemical, traction and tribofilm formation properties of three octanoate-, laurate- and palmitate-anion based ionic liquids

Three new ionic liquids with different anions and the same cation were synthesized from fatty acids through a metathesis reaction.All the ionic liquidswere identified viaNMRand FTIR and several properties (density, viscosity, thermal, and environmental) were measured. Traction tests were performed under different entrainment speeds (10–2000 mm/s), at slide-roll ratio (SRR) of 50% and 30 N-load, and at different temperatures (40, 60, 80 and 100 °C) using a mini-traction machine (MTM). Tribofilm formation tests were also made in the MTM at 50 N-load, 150 mm/s of entrainment speed, at SRR of 50% and temperature of 100 °C, for 60 min. This work showed that the alkyl chain length in the anion affects properties such as viscosity, toxicity, biodegradability and lubrication. Viscosity decreased with increasing alkyl chain length but only below 60 °C, at higher temperatures the viscosity values of the ionic liquids converge. The toxicity increases with the alkyl chain length; whereas, biodegradability shows the opposite behavior. These novel ionic liquids are much better from both toxicity and biodegradability points of view than the [N8881][TFSI] ionic liquid, which contains the same cation and anion not coming from fatty acids. The ionic liquids at low temperature (40 °C) performed under elastohydrodynamic lubrication and changed to mixed lubrication at higher temperatures and decreasing speeds, according to the alkyl chain length of each anion. All ionic liquids adsorbed on the steel surfaces, and the tribofilm thickness and the kinetics of formation were different

High Energy Cosmic Rays from Neutrinos

We discuss recent models in which neutrinos, which are assumed to have mass in the eV range, originate the highest energy cosmic rays by interaction with the enhanced density in the galactic halo of the relic cosmic neutrino background. We make an analytical calculation of the required neutrino fluxes to show that the parameter space for these models is constrained by horizontal air shower searches and by the total number of background neutrinos, so that only models which have fairly unnatural halo sizes and enhanced densities are allowed.Comment: 14 pages, 3 ps figures. To appear in Phys. Rev.

Adatok a Pádis karsztvidékének (Bihari-hegység) mohaflórájához = Date privind flora de briofite din ţinutul carstic Padiş (Munţii Bihorului) = Some data to the bryophyte flora of the Padiş area (Bihor Mountains)

While some web search users know exactly what they are looking for, others are willing to explore topics related to an initial interest. Often, the user's initial interest can be uniquely linked to an entity in a knowledge base. In this case, it is natural to recommend the explicitly linked entities for further exploration. In real world knowledge bases, however, the number of linked entities may be very large and not all related entities may be equally relevant. Thus, there is a need for ranking related entities. In this paper, we describe Spark, a recommendation engine that links a user's initial query to an entity within a knowledge base and provides a ranking of the related entities. Spark extracts several signals from a variety of data sources, including Yahoo! Web Search, Twitter, and Flickr, using a large cluster of computers running Hadoop. These signals are combined with a machine learned ranking model in order to produce a final recommendation of entities to user queries. This system is currently powering Yahoo! Web Search result pages. © 2013 Springer-Verlag

Mechanical canopy and trunk shaking for the harvesting mechanization of table olive orchards

Table olive harvesting is highly dependent on manual labour and may jeopardize the crop benefit. The introduction of a mechanical harvest system requires a global evaluation of the whole process. A trunk shaker along with shaker combs and a continuous canopy shaker harvester have been tested in two orchards with different tree training and layout to determine their feasibility to mechanical harvesting in table olives. For that purpose, several parameters have been evaluated. Canopy shaker required adapted orchard layout and hedge of canopies for reaching an acceptable harvesting efficiency about 80% and trunk shaker performed a higher efficiency of more than 95% but depended highly on labour. Both systems had a high field capacity about 0.15 ha h-1 but low for the trunk shaker considering the people (0.01 ha h-1 person-1). The vibration pattern that applied on branches was totally different although the quantitative tree damages were no significative different. There were no significant differences in fruit bruising between both systems, but there were between the different sampling points, mainly in the detachment. The fruit bruising index of the remaining fruit on canopy suggests that it is possible to perform a second harvest. Both mechanical systems are suitable for table olive harvesting whilst improving the efficiency of manual systems with bearable damages, but each one has pros and cons that must be considered bearing in mind that require an adaptation of the orchard where there are applied. Highlights Table olives mechanization is possible by integrating with the fruit liquid store. Trunk shaker performed high efficiency in adapted orchards but depended on labour. Canopy shakers require the adaption of orchard and machine for commercial purposes. There were no differences in detached fruit bruising between both mechanical systems. The bruising index of the remaining fruit on trees suggest second harvesting pass.Table olive harvesting is highly dependent on manual labour and may jeopardize the crop benefit. The introduction of a mechanical harvest system requires a global evaluation of the whole process. A trunk shaker along with shaker combs and a continuous canopy shaker harvester have been tested in two orchards with different tree training and layout to determine their feasibility to mechanical harvesting in table olives. For that purpose, several parameters have been evaluated. Canopy shaker required adapted orchard layout and hedge of canopies for reaching an acceptable harvesting efficiency about 80% and trunk shaker performed a higher efficiency of more than 95% but depended highly on labour. Both systems had a high field capacity about 0.15 ha h-1 but low for the trunk shaker considering the people (0.01 ha h-1 person-1). The vibration pattern that applied on branches was totally different although the quantitative tree damages were no significative different. There were no significant differences in fruit bruising between both systems, but there were between the different sampling points, mainly in the detachment. The fruit bruising index of the remaining fruit on canopy suggests that it is possible to perform a second harvest. Both mechanical systems are suitable for table olive harvesting whilst improving the efficiency of manual systems with bearable damages, but each one has pros and cons that must be considered bearing in mind that require an adaptation of the orchard where there are applied. Highlights Table olives mechanization is possible by integrating with the fruit liquid store. Trunk shaker performed high efficiency in adapted orchards but depended on labour. Canopy shakers require the adaption of orchard and machine for commercial purposes. There were no differences in detached fruit bruising between both mechanical systems. The bruising index of the remaining fruit on trees suggest second harvesting pass

Glucocorticoids improve acute dizziness symptoms following acute unilateral vestibulopathy.

Acute unilateral vestibulopathy (AUV) is characterized by acute vertigo, nausea, and imbalance without neurological deficits or auditory symptomatology. Here, we explore the effect of glucocorticoid treatment on the degree of canal paresis in patients with AUV, and critically, establish its relationship with dizziness symptom recovery. We recruited consecutive patients who were retrospectively assigned to one of the two groups according to whether they received glucocorticoid treatment (n = 32) or not (n = 44). All patients underwent pure-tone audiometry, bithermal caloric testing, MRI brain imaging, and were asked to complete a dizziness handicap inventory on admission to hospital and just prior to hospital discharge. In the treatment group, the canal paresis at discharge was significantly lower than in the control group (mean ± SD % 38.04 ± 21.57 versus 82.79 ± 21.51, p < 0.001). We also observed a significant reduction in the intensity of nystagmus in patients receiving glucocorticoid treatment compared to the non-treatment group (p = 0.03). DHI test score was significantly lower at discharge in the treatment group (mean ± SD % 23.15 ± 12.40 versus 64.07 ± 12.87, p < 0.001), as was the length of hospital stay (2.18 ± 1.5 days versus 3.6 ± 1.7 days, p = 0.002). Glucocorticoid treatment leads to acute symptomatic improvement, with a reduced hospital stay and reduction in the intensity of acute nystagmus. Our findings suggest that glucocorticoids may accelerate vestibular compensation via a restoration of peripheral vestibular function, and therefore has important clinical implications for the treatment of AUV

Lubrication Properties of the Ionic Liquid Dodecyl-3 Methylimidazolium bis(trifluoromethylsulfonyl)imide

© 2017, Springer Science+Business Media, LLC, part of Springer Nature. The ionic liquid (IL) dodecyl-3 methylimidazolium bis(trifluoromethylsulfonyl)imide was tested as neat lubricant and as additive (at 1 and 4 wt%) in a polar oil (diester). Tribological tests were performed using a reciprocating configuration for 90 min at 30 and 70 N, 10 Hz, 4 mm stroke length, and at room temperature and 100 °C. Wear volume and surface–IL interaction were determined by confocal microscopy, SEM, and XPS. The main findings were: Neat ionic liquid showed the best tribological behavior; the IL-containing mixtures had similar behavior than the base oil at the lower load; meanwhile, the mixture with 4 wt% of IL outperformed the antiwear behavior of the neat base oil at the higher load; surface–IL chemical interaction was found mainly at 100 °C