Method of fabricating a photovoltaic module of a substantially transparent construction

A method characterized by the steps of positioning a plurality of uniformly dimensioned photovoltaic cells in registered relation with a plurality of openings formed in a planar tool is disclosed. The method allows acess to the P contact surface of each of the cells. The steps of the method are: (1) connecting the N contact surface of alternate cells to the P contact surface of the cells interposed therebetween, (2) removing therefrom residue of solder flux, (3) applying to the N contact surfaces of the cells a transparent adhesive, (4) placing a common transparent cover plate in engaged relation with the adhesive, (5) placing a film over the circular openings for hermetically sealing the openings, and (6) establishing a vacuum between the film and the cover plate

Optimization of Al/AlOx/AlAl/AlO_x/Al-Layer Systems for Josephson Junctions from a Microstructure Point of View

$Al/AlO_x/Al$-layer systems are frequently used for Josephson junction-based superconducting devices. Although much work has been devoted to the optimization of the superconducting properties of these devices, systematic studies on influence of deposition conditions combined with structural analyses on the nanoscale are rare up to now. We have focused on the optimization of the structural properties of $Al/AlO_x/Al$-layer systems deposited on Si(111) substrates with a particular focus on the thickness homogeneity of the $AlO_x$-tunnel barrier. A standard high-vacuum electron-beam deposition system was used and the effect of substrate pretreatment, different Al-deposition temperatures and Al-deposition rates was studied. Transmission electron microscopy was applied to analyze the structural properties of the $Al/AlO_x/Al$-layer systems to determine the thickness homogeneity of the $AlO_x$ layer, grain size distribution in the Al layers, Al-grain boundary types and the morphology of the $Al/AlO_x$ interface. We show that the structural properties of the lower Al layer are decisive for the structural quality of the whole $Al/AlO_x/Al$-layer system. Optimum conditions yield an epitaxial Al(111) layer on a Si(111) substrate with an Al-layer thickness variation of only 1.6 nm over more than 10 $\mu m$ and large lateral grain sizes up to 1 $\mu m$. Thickness fluctuations of the $AlO_x$-tunnel barrier are minimized on such an Al layer which is essential for the homogeneity of the tunnel current. Systematic variation of the Al-deposition rate and deposition temperature allows to develop an understanding of the growth mechanisms

A Technique to Derive Improved Proper Motions for Kepler Objects of Interest

We outline an approach yielding proper motions with higher precision than exists in present catalogs for a sample of stars in the Kepler field. To increase proper motion precision we combine first moment centroids of Kepler pixel data from a single Season with existing catalog positions and proper motions. We use this astrometry to produce improved reduced proper motion diagrams, analogous to a Hertzsprung-Russell diagram, for stars identified as Kepler Objects of Interest. The more precise the relative proper motions, the better the discrimination between stellar luminosity classes. With UCAC4 and PPMXL epoch 2000 positions (and proper motions from those catalogs as quasi-bayesian priors) astrometry for a single test Channel (21) and Season (0) spanning two years yields proper motions with an average per-coordinate proper motion error of 1.0 millisecond of arc per year, over a factor of three better than existing catalogs. We apply a mapping between a reduced proper motion diagram and an HR diagram, both constructed using HST parallaxes and proper motions, to estimate Kepler Object of Interest K-band absolute magnitudes. The techniques discussed apply to any future small-field astrometry as well as the rest of the Kepler field.Comment: Accepted to The Astronomical Journal 15 August 201

Optimization conditions of UV-C radiation combined with ultrasound-assisted extraction of cherry tomato (Lycopersicon esculentum) lycopene extract

The aim of this work was to study the effect of UV-C radiation on ultrasound assisted extraction (UAE) of cherry tomato bioactive compounds. Cherry tomatoes were exposed to two UV-C radiation doses (0.5 and 1.0 J cm−2 ) and stored at 20 ± 0.5 oC for 7 days. Next, they were lyophilized, and the bioactive compounds were extracted by UAE at 20 KHz. To evaluate the effectiveness of the extraction process of the bioactive compounds, a CCRD (central composite rotational design) was used together with RSM (response surface methodology), for extraction times from 4 to 12 minutes and concentrations (g of lyophilized product / L of ethanol) of 1:10, 1:20 and 1:30. The extracts obtained from the irradiated tomatoes presented 5.8 times more lycopene content than the controls and higher antioxidant activity was obtained for 4 and 8 min, in the concentrations 1:10 and 1:20 (m v−1). Through numerical model optimization, optimal extraction conditions were obtained. The results demonstrated that by previously irradiating tomatoes with UV-C light, the UAE yielded considerably higher amounts of lycopene and other bioactives.CNPq (National Council of Technological and Scientific Development, Brazil), Erasmus Mundus action 2; Fellow Mundus Project; Department of Chemical Engineering and Food Engineering (UFSC - Brazil) and the Department of Food Engineering (UAlg - Portugal) .info:eu-repo/semantics/publishedVersio

The evolution of the number density of compact galaxies

We compare the number density of compact (small size) massive galaxies at low and high redshift using our Padova Millennium Galaxy and Group Catalogue (PM2GC) at z=0.03-0.11 and the CANDELS results from Barro et al. (2013) at z=1-2. The number density of local compact galaxies with luminosity weighted (LW) ages compatible with being already passive at high redshift is compared with the density of compact passive galaxies observed at high-z. Our results place an upper limit of a factor ~2 to the evolution of the number density and are inconsistent with a significant size evolution for most of the compact galaxies observed at high-z. The evolution may be instead significant (up to a factor 5) for the most extreme, ultracompact galaxies. Considering all compact galaxies, regardless of LW age and star formation activity, a minority of local compact galaxies (<=1/3) might have formed at z<1. Finally, we show that the secular decrease of the galaxy stellar mass due to simple stellar evolution may in some cases be a non-negligible factor in the context of the evolution of the mass-size relation, and we caution that passive evolution in mass should be taken into account when comparing samples at different redshifts.Comment: ApJ in pres

Detailed Abundances for the Old Population near the Galactic Center: I. Metallicity distribution of the Nuclear Star Cluster

We report the first high spectral resolution study of 17 M giants kinematically confirmed to lie within a few parsecs of the Galactic Center, using R=24,000 spectroscopy from Keck/NIRSPEC and a new linelist for the infrared K band. We consider their luminosities and kinematics, which classify these stars as members of the older stellar population and the central cluster. We find a median metallicity of =-0.16 and a large spread from approximately -0.3 to +0.3 (quartiles). We find that the highest metallicities are [Fe/H]<+0.6, with most of the stars being at or below the Solar iron abundance. The abundances and the abundance distribution strongly resembles that of the Galactic bulge rather than disk or halo; in our small sample we find no statistical evidence for a dependence of velocity dispersion on metallicity.Comment: 18 pages, 14 figures, accepted for publication in A

Trust in the US-EU fruit and vegetable chain: Do US exporters understand EU importers?

Research on organizational and inter organizational trust has become an important field in management and marketing literature, as it is perceived as a pivotal aspect of business transactions. However, clarifications are still needed on the issue of whom we trust; is the person whom we are trading with trusted, or the organization, or just the product‐quality? Not only has this question not been answered within this field of research, neither have cultural differences have been described to any great extent. Additionally, if the perceived factors important to establish trusting relationships may or may not be the same on the buyers and the sellers side in international business transaction in food chains. The primary objective of this research study therefore is to identify how well US exporters understand the elements of trust that establish strong relationships with EU importers. The Analytical Hierarchy Process was used to evaluate the importance of different trust elements in interviews conducted with US exporters and EU importers of fruits and vegetables. Results are compared, providing both a picture of the important facets of trust, as well as whether the partners understand the perspectives of the other partner

Correlating the nanostructure of Al-oxide with deposition conditions and dielectric contributions of two-level systems in perspective of superconducting quantum circuits

This work is concerned with Al/Al-oxide(AlO$_{x}$)/Al-layer systems which are important for Josephson-junction-based superconducting devices such as quantum bits. The device performance is limited by noise, which has been to a large degree assigned to the presence and properties of two-level tunneling systems in the amorphous AlO$_{x}$ tunnel barrier. The study is focused on the correlation of the fabrication conditions, nanostructural and nanochemical properties and the occurrence of two-level tunneling systems with particular emphasis on the AlO$_{x}$-layer. Electron-beam evaporation with two different processes and sputter deposition were used for structure fabrication, and the effect of illumination by ultraviolet light during Al-oxide formation is elucidated. Characterization was performed by analytical transmission electron microscopy and low-temperature dielectric measurements. We show that the fabrication conditions have a strong impact on the nanostructural and nanochemical properties of the layer systems and the properties of two-level tunneling systems. Based on the understanding of the observed structural characteristics, routes are derived towards the fabrication of Al/AlO$_{x}$/Al-layers systems with improved properties.Comment: 28 pages, 4 figure