Performance studies of a full-length prototype for the CASTOR forward calorimeter at the CMS experiment

The Time-Of-Flight detector (TOF) of the ALICE experiment at the CERN LHC is based on Multi-gap Resistive Plate Chambers (MRPCs). The TOF detector consists of 152928 readout channels covering a total area of 141 m². In this paper the results of the calibration with cosmic-ray data collected during 2009 are presented.     

Testing metric-affine f(R)-gravity by relic scalar gravitational waves

We discuss the emergence of scalar gravitational waves in metric-affine f(R)-gravity. Such a component allows to discriminate between metric and metric-affine theories The intrinsic meaning of this result is that the geodesic structure of the theory can be discriminated. We extend the formalism of cross-correlation analysis, including the additional polarization mode, and calculate the detectable energy density of the spectrum for cosmological relic gravitons. The possible detection of the signal is discussed against the sensitivities of the VIRGO, LIGO and LISA interferometers.     

Compression behavior of elastomeric networks-non-equilibrium effects

The compression behavior of some rubberlike networks in equilibrium and non-equilibrium conditions has been investigated. The experimental data clearly indicate that non-equilibrium components are operative on the compression modulus value. Results are interpreted in terms of supramolecular order in the amorphous materials.     

Core-level photoelectron study of indium chains on Si(1 1 1) at 10 K

High-resolution core-level data from the prototypical In/Si(1 1 1) system have been acquired at 10 K. An asymmetric tail in the In 4d spectra reveals a metallic character of the low temperature Si(1 1 1)8 × 2 phase confined to the inner indium rows. The decoupling of the one-dimensional inner indium chains from any metallic environment at ∼10 K suggests a possible Luttinger liquid behavior. At room temperature essentially a broadening of the spectral features is noticed, which appears compatible with a fluctuation scenario.     

Perthamides C-F, potent human antipsoriatic cyclopeptides

Two new cyclopeptides, perthamides E and F were isolated from the polar extracts of the sponge Theonella swinhoei. The new structures, featuring an unprecedented β-amino acid unit (AHMOA), were determined by interpretation of NMR and MS data. The absolute configuration of the AHMOA residue was proposed on the basis of quantum chemical calculation of NMR chemical shifts. Perthamides were proved to inhibit TNF-α and IL-8 release in primary human keratinocytes cells and therefore could represent potentially leads for the treatment of psoriasis.     

Thermal behavior study of biodiesel standard reference materials

Quality control of fuel-related properties of biodiesel, such as thermal stability, is needed to obtain consistent engine performance by fuel users, since biodiesel is susceptible to auto-oxidation when exposed to air, light, and temperature during storage. In this work two pure standard reference materials of biodiesels produced from soy oil and animal feedstocks were studied. Differential scanning calorimetry and thermogravimetry measurements were performed and the analysis of the results revealed small temperature variations in the thermal events among the two standards, these differences are due mainly to their chemical composition, been highly influenced by the amounts of unsaturated esters.     

Experimental and theoretical analysis of bias ionization by?α-particles in a nitrogen laser

Nitrogen laser performance with TE configuration and wedge electrodes is analyzed with background ionization in the laser discharge channel by α particles at a low exposition rate. With the bias ionization, the laser power presents two peaks as a function of gas pressure, with one at the normal low pressure, without bias ionization, and the other at high pressure generated by bias ionization. A simple theoretical model has been developed in a trial to understand this behavior. This model was first tested in later results for a TE configuration nitrogen laser, with flat electrodes, without and with bias ionization. It has been observed that due to the competition between electrode shielding by positively charged α particles and bulk ionization by impact, the laser energy is suppressed with pressure below 50 Torr and enhanced above it.