126 research outputs found
Coulombic Retardation Effect of »Neutral« Electrolytes on Formation of Barium Sulfate Crystallites (Reversal of Schulze-Hardy Rule)
The formation of precipitates by mixing the diluted solutions
of barium nitrate and sodium sulfate (w ith sulfate in excess) and
in presence of various concentrations of potassium, magn esi um,
and lanthanum nitrate, was followed tyndallometricall y. It was
found that there are critical concentrations of counter ions of the
s ame order as with Schulze-Hardy rule but of opposite effect: at
higher concentrations there was a distinct retardation in the
formation of particles. The effect may b e. explained as the result
of coulombic interactions in the formation of ion pairs or complexes
between sulfate and cou\u27nter ions causing either a slower embrionation,
or a hindrance of direct growth, and/ or a retardation of
the aggregation of growing nuclei into l arger crystallites
ENERGY EFFICIENCY INDICATORS
U radu su opisani indikatori energetske učinkovitosti i indeksi poboljšanja
energetske učinkovitosti prema vrsti i namjeni. Namjena indikatora i indeksa
je praćenje i uspoređivanje trendova energetske učinkovitosti u zemljama EU-
27, Norveškoj i Hrvatskoj, stoga su posebno prikazani trendovi u Hrvatskoj za
svaki od sektora potrošnje energije.This paper describes energy efficiency indicators and indices of energy
efficiency improvements according to type and use. The purpose of indicators
and indices is the monitoring and comparing of energy efficiency trends in the
EU-27 countries, Norway and the Republic of Croatia, therefore the trends
in Croatia have been specially presented for each of the energy consumption
sectors
CO2 and H2 Adsorption and Reaction at Nin/YSZ(111) Interfaces: A Density Functional Theory Study
To recycle CO2 into sustainable fuels and chemicals, coelectrolysis of CO2 and H2O can be achieved in solid oxide electrolysis cells, where the molecules are supplied to the Ni/YSZ electrode (YSZ = yttria-stabilized zirconia). Oxygen diffusion along the electrode has been identified as the critical step in the process, where YSZ is the common catalyst support. We have investigated the interaction of a CO2 molecule with the clean YSZ(111) surface and with Nin/YSZ(111) (n = 1, 4–7, 10, and 20) interfaces, using a spin-polarized density functional theory and a long-range dispersion correction. Here, we have considered up to six initial adsorption sites and two orientations for the CO2 molecule, which showed that the adsorption is stronger at the Nin/YSZ(111) (n = 4–7, 10, and 20) interface than on the clean YSZ(111) and Ni1/YSZ(111) systems. Additionally, we have determined that the preferential adsorption site of CO2 is at the interface between the Ni clusters and the YSZ(111) surface. We have observed a bending and stretching of the molecule, demonstrating its activation upon adsorption, because of charge transfer between the metal cluster and the molecule and a mixing between Ni orbitals and CO2 orbitals. In this work, we show that although the electronic structure of the clusters depends on the cluster size, the interaction strength of CO2 with the interface is independent of the size of the supported nickel particle. Finally, we have considered the reverse water gas shift reaction and determined the hydrocarboxylic intermediate in the reaction mechanism over Ni5/YSZ(111)
The utility of Tc-99m-EDDA/HYNIC-TOC scintigraphy for assessment of lung lesions in patients with neuroendocrine tumors
Our aim was to assess clinical utility of Tc-99m-EDDA/HYNIC-TOC scintigraphy for evaluation of lung lesions in patients with neuroendocrine tumors (NETs). Single photon emission computed tomography (SPECT) of the thorax and whole body scintigraphy were performed in 34 patients using Tc-99m-EDDA/HYNIC-TOC. Visual assessment was complemented by semiquantitative evaluation based on tumor to non-tumor (TINT) ratio. Clinical, laboratory, and histological findings served as the standard for comparison. Enhanced tracer uptake was observed on both SPECT and whole body scintigraphy in 29 of 34 patients (88% sensitivity). TINT ratios were significantly higher on SPECT than whole body images (2.96 +/- 1.07 vs. 1.70 +/- 0.43, p LT 0.01) and did not correlate with NET proliferation index Ki-67 (r= - 0.36, p=0.27). Conclusion: Tc-99m-EDDA/HYNIC-TOC scintigraphy is useful for evaluation of NET tissue in the lungs. SPECT provides better visualization of lung lesions than whole body scintigraphy. The intensity of tracer uptake, however, does not relate to the proliferation rate of NETs. Tc-99m-EDDA/HYNIC-TOC scintigraphy may be helpful for selecting and monitoring treatment options, particularly when radiolabeled somatostatin analogue therapy becomes available
Measured and projected beam backgrounds in the Belle II experiment at the SuperKEKB collider
The Belle II experiment at the SuperKEKB electron-positron collider aims to
collect an unprecedented data set of to study -violation
in the -meson system and to search for Physics beyond the Standard Model.
SuperKEKB is already the world's highest-luminosity collider. In order to
collect the planned data set within approximately one decade, the target is to
reach a peak luminosity of by further
increasing the beam currents and reducing the beam size at the interaction
point by squeezing the betatron function down to . To ensure detector longevity and maintain good reconstruction
performance, beam backgrounds must remain well controlled. We report on current
background rates in Belle II and compare these against simulation. We find that
a number of recent refinements have significantly improved the background
simulation accuracy. Finally, we estimate the safety margins going forward. We
predict that backgrounds should remain high but acceptable until a luminosity
of at least is reached for
. At this point, the most vulnerable Belle II
detectors, the Time-of-Propagation (TOP) particle identification system and the
Central Drift Chamber (CDC), have predicted background hit rates from
single-beam and luminosity backgrounds that add up to approximately half of the
maximum acceptable rates.Comment: 28 pages, 17 figures, 9 tables (revised
3D Bioprinted Human Skeletal Muscle Constructs for Muscle Function Restoration
A bioengineered skeletal muscle tissue as an alternative for autologous tissue flaps, which mimics the structural and functional characteristics of the native tissue, is needed for reconstructive surgery. Rapid progress in the cell-based tissue engineering principle has enabled in vitro creation of cellularized muscle-like constructs; however, the current fabrication methods are still limited to build a three-dimensional (3D) muscle construct with a highly viable, organized cellular structure with the potential for a future human trial. Here, we applied 3D bioprinting strategy to fabricate an implantable, bioengineered skeletal muscle tissue composed of human primary muscle progenitor cells (hMPCs). The bioprinted skeletal muscle tissue showed a highly organized multi-layered muscle bundle made by viable, densely packed, and aligned myofiber-like structures. Our in vivo study presented that the bioprinted muscle constructs reached 82% of functional recovery in a rodent model of tibialis anterior (TA) muscle defect at 8 weeks of post-implantation. In addition, histological and immunohistological examinations indicated that the bioprinted muscle constructs were well integrated with host vascular and neural networks. We demonstrated the potential of the use of the 3D bioprinted skeletal muscle with a spatially organized structure that can reconstruct the extensive muscle defects
Interim 2017/18 influenza seasonal vaccine effectiveness: Combined results from five European studies
Between September 2017 and February 2018, influenza A(H1N1)pdm09, A(H3N2) and B viruses (mainly B/Yamagata, not included in 2017/18 trivalent vaccines) co-circulated in Europe. Interim results from five European studies indicate that, in all age groups, 2017/18 influenza vaccine effectiveness was 25 to 52% against any influenza, 55 to 68% against influenza A(H1N1)pdm09, -42 to 7% against influenza A(H3N2) and 36 to 54% against influenza B. 2017/18 influenza vaccine should be promoted where influenza still circulates
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