408 research outputs found

    Evaluation of the Mineral Element Profile of Wastes of Some Wine Grape (Vitis Vinifera L.) Varieties

    Full text link
    In this study, the level of macro and micro elements of six wine grape cultivars were determined in seeds, bagasse (skin and pulp) and pomace (seed, skin and pulp) by inductively coupled plasma mass spectrometry and atomic absorption spectroscopy after microwave digestion (ICP-AES). The levels of macro and micro elements exhibited a genotype dependent alteration and affected by the part of the berry sampled. Potassium was the predominant macro element in bagasse and pomace, varying from 6.78 g/kg dry weight in pomace (Carignane) to 21.05 g/kg dry weight in bagasse (Cabernet Sauvignon). However, the level of calcium was higher than potassium in seeds and varied between 4.95 g/kg (Kalecik karası) and 6.73 g/kg (Carignane). Seeds were also richer than the bagasse and pomace related with phosphorus, magnesium, and sulfur. Among the micro elements, Fe had the highest amount in all parts of the berries. Its content ranged from 13.9 mg/kg dry weights in bagasse of Semillon to 24.8 mg/kg dry weight in seeds of Syrah. Iron, manganese, zinc and molybdenum in seeds; copper and boron in bagasse were higher amount than the other groups analyzed. The results of this study show that all parts of the grape berries are potentially rich sources of mineral elements. So, they could be used as a food supplement to improve the nutritive value of the human diet and for some engineering processes in food industry

    Exploring the precision of femtosecond laser-assisted descemetorhexis in Descemet membrane endothelial keratoplasty

    Get PDF
    Objective Descemet membrane endothelial keratoplasty (DMEK) remains a challenging technique. We compare the precision of femtosecond laser-assisted DMEK to manual DMEK. Methods and Analysis A manual descemetorhexis (DR) of 8 mm diameter was compared with a femtosecond laser-assisted DR of the same diameter (femto-DR) in 22 pseudophakic patients requiring DMEK. We used OCT images with a centred xy-diagram to measure the postoperative precision of the DR and the amount of endothelial denuded area. Endothelial cell loss (ECL) and best corrected visual acuity were measured 3 months after surgery. Results In the manual group, the median error of the DR was 7% (range 3%-16%) in the x-diameter and 8% (range 2%-17%) in the y-diameter. In the femto group, the median error in the respective x and y-diameters was 1% (range 0.4%-3%) and 1% (range 0.006%-2.5%), smaller than in the manual group (p=0.001). Endothelial denuded areas were larger in the manual group (11.6 mm(2), range 7.6-18 mm(2)) than in the femto group (2.5 mm(2), range 1.25.9 mm(2)) (p<0.001). The ECL was 21% (range 5%-78%) in the manual DR and 17% (range 6%-38%) in the femto-DR group (p=0.351). The median visual acuity increased from 0.4 logMAR (range 0.6-0.4 logMAR) in both groups to 0.1 logMAR (range 0.4-0 logMAR) in the manual group and to 0.1 logMAR (range 0.3-0 logMAR) in the femto group (p=0.461). Three rebubblings were required in the manual group, whereas the femto group required only one. Conclusion The higher precision of the femto-DR bears the potential to improve DMEK surgery

    Surface Acoustic Waves to Control Droplet Impact onto Superhydrophobic and Slippery Liquid-Infused Porous Surfaces

    Get PDF
    Superhydrophobic coatings and slippery liquid-infused porous surfaces (SLIPS) have shown their potentials in self-cleaning, anti-icing, anti-erosion, and antibiofouling applications. Various studies have been done on controlling the droplet impact on such surfaces using passive methods such as modifying the lubricant layer thickness in SLIPS. Despite their effectiveness, passive methods lack on-demand control over the impact dynamics of droplets. This paper introduces a new method to actively control the droplet impact onto superhydrophobic and SLIPS surfaces using surface acoustic waves (SAWs). In this study, we designed and fabricated SLIPS on ZnO/aluminum thin-film SAW devices and investigated different scenarios of droplet impact on the surfaces compared to those on similar superhydrophobic-coated surfaces. Our results showed that SAWs have insignificant influences on the impact dynamics of a porous and superhydrophobic surface without an infused oil layer. However, after infusion with oil, SAW energy could be effectively transferred to the droplet, thus modifying its impact dynamics onto the superhydrophobic surface. Results showed that by applying SAWs, the spreading and retraction behaviors of the droplets are altered on the SLIPS surface, leading to a change in a droplet impact regime from deposition to complete rebound with altered rebounding angles. Moreover, the contact time was reduced up to 30% when applying SAWs on surfaces with an optimum oil lubricant thickness of ∼8 μm. Our work offers an effective way of applying SAW technology along with SLIPS to effectively reduce the contact time and alter the droplet rebound angles

    The experimental program for high pressure gas filled radio frequency cavities for muon cooling channels

    Get PDF
    An intense beam of muons is needed to provide a luminosity on the order of 10(34) cm(-2)s(-1) for a multi-TeV collider. Because muons produced by colliding a multi-MW proton beam with a target made of carbon or mercury have a large phase space, significant six dimensional cooling is required. Through ionization cooling - the only cooling method that works within the lifetime of the muon - and emittance exchange, the desired emittances for a Higgs Factory or higher energy collider are attainable. A cooling channel utilizing gas filled radio frequency cavities has been designed to deliver the requisite cool muon beam. Technology development of these RF cavities has progressed from breakdown studies, through beam tests, to dielectric loaded and reentrant cavity designs. The results of these experiments are summarized

    Antiproton Production in p+Ap+A Collisions at AGS Energies

    Full text link
    Inclusive and semi-inclusive measurements are presented for antiproton (pˉ\bar{p}) production in proton-nucleus collisions at the AGS. The inclusive yields per event increase strongly with increasing beam energy and decrease slightly with increasing target mass. The pˉ\bar{p} yield in 17.5 GeV/c p+Au collisions decreases with grey track multiplicity, NgN_g, for Ng>0N_g>0, consistent with annihilation within the target nucleus. The relationship between NgN_g and the number of scatterings of the proton in the nucleus is used to estimate the pˉ\bar{p} annihilation cross section in the nuclear medium. The resulting cross section is at least a factor of five smaller than the free pˉp\bar{p}-p annihilation cross section when assuming a small or negligible formation time. Only with a long formation time can the data be described with the free pˉp\bar{p}-p annihilation cross section.Comment: 8 pages, 6 figure

    Pressurized H-2 rf Cavities in Ionizing Beams and Magnetic Fields

    Get PDF
    A major technological challenge in building a muon cooling channel is operating rf cavities in multitesla external magnetic fields. We report the first proof-of-principle experiment of a high pressure gas-filled rf cavity for use with intense ionizing beams and strong external magnetic fields. rf power consumption by beam-induced plasma is investigated with hydrogen and deuterium gases with pressures between 20 and 100 atm and peak rf gradients between 5 and 50 MV/m. The low pressure case agrees well with an analytical model based on electron and ion mobilities. Varying concentrations of oxygen gas are investigated to remove free electrons from the cavity and reduce the rf power consumption. Measurements of the electron attachment time to oxygen and rate of ion-ion recombination are also made. Additionally, we demonstrate the operation of the gas-filled rf cavity in a solenoidal field of up to 3 T, finding no major magnetic field dependence. All these results indicate that a high pressure gas-filled cavity is a viable technology for muon ionization cooling.open1

    Muon Colliders

    Full text link
    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity \mumu colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.Comment: 28 pages, with 12 postscript figures. To be published Proceedings of the 9th Advanced ICFA Beam Dynamics Workshop, AIP Pres
    corecore