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Graphane is formed by bonding hydrogen (and deuterium) atoms to carbon atoms in the graphene mesh, with modification from the pure planar sp2 bonding towards an sp3 configuration. Atomic hydrogen (H) and deuterium (D) bonding with C atoms in fully free-standing nano porous graphene (NPG) is achieved, by exploiting low-energy proton (or deuteron) non-destructive irradiation, with unprecedented minimal introduction of defects, as determined by Raman spectroscopy and by the C 1s core level lineshape analysis. Evidence of the H- (or D-) NPG bond formation is obtained by bringing to light the emergence of a H- (or D-) related sp3-distorted component in the C 1s core level, clear fingerprint of H–C (or D–C) covalent bonding. The H (or D) bonding with the C atoms of free-standing graphene reaches more than 1/4 (or 1/3) at% coverage. This non-destructive H-NPG (or D-NPG) chemisorption is very stable at high temperatures up to about 800 K, as monitored by Raman and x-ray photoelectron spectroscopy, with complete healing and restoring of clean graphene above 920 K. The excellent chemical and temperature stability of H- (and D-) NPG opens the way not only towards the formation of semiconducting graphane on large-scale samples, but also to stable graphene functionalisation enabling futuristic applications in advanced detectors for the β-spectrum analysis.

Polycyclic aromatic hydrocarbons (PAHs) are widespread and harmful environmental pollutants that threaten marine ecosystems. Assessing their level and source is crucial to estimate the potential risks for marine organisms, as PAHs represent an additional threat to organism resilience under ongoing climatic change. Here we applied the QuEChERS extraction method to quantify four PAHs (i.e. acenaphthene, fluorene, fluoranthene, and pyrene) in three biological compartments (i.e. skeleton, tissue, and zooxanthellae symbiotic algae) of adult and old specimens of a scleractinian coral species (Balanophyllia europaea) that is widespread throughout the Mediterranean Sea. A higher concentration of all four investigated PAHs was observed in the zooxanthellae, followed by the coral tissue, with lowest concentration in the skeleton, consistently with previous studies on tropical species. In all the three biological compartments, the concentration of low molecular weight PAHs was higher with respect to high-molecular weight PAHs, in agreement with their bioaccumulation capabilities. PAH concentration was unrelated to skeletal age. Observed PAHs were of petrogenic origin, reflecting the pollution sources of the sampling area. By coupling PAH data with population age structure data measured in the field, the amount of PAHs stored in the long term (i.e. up to 20 years) in coral skeletons was quantified and resulted in 53.6 ng m−2 of acenaphthene, 69.4 ng m−2 of fluorene, 2.7 ng m−2 of fluoranthene, and 11.7 ng m−2 of pyrene. This estimate provides the basis for further assessments of long-term sequestration of PAHs from the marine environment in the whole Mediterranean, given the widespread distribution of the investigated coral species.

Multiple scattering effects of 12 and 20 GeV electrons on 8 and 20 mm thickness carbon targets have been studied with high-resolution silicon microstrip detectors of the UA9 apparatus at the H8 line at CERN. Comparison of the scattering angle between data and GEANT4 simulation shows excellent agreement in the core of the distributions leaving some residual disagreement in the tails., 14 pages, 16 figures. Updated to match published version

Gluten represents one of the principal by-products of the wheat starch industry. Peptides obtained by wheat hydrolysis can be used for specific functional and biological activities, albeit at relatively low yields. Although the Maillard reaction (glycation) is widely used to increase functionality of proteins, its main disadvantage is the production of undesirable compounds due to high processing temperature. In this research, functional and biologically active glycopeptides were obtained from gluten. Alcalase or Flavourzyme proteases were used to hydrolyse gluten protein, and the resulting peptides were conjugated with glucosamine by enzymatic glycosylation, using transglutaminase, or through glycation. Both reactions were performed at mild temperatures (25 or 37°C). The formation of glycopeptides depended mostly on the glycation process, as demonstrated by MALDI-TOF-MS. The bioactivities of the conjugated hydrolysates were compared to the native hydrolysates. Although a reduction in the anti-ACE activity was detected, improved DPPH scavenging activity and enhanced antimicrobial activity against Escherichia coli were observed in the glycated Alcalase-derived hydrolysates and in the glycated Flavourzyme-derived hydrolysates, respectively. This study showed that mild conditions are an alternate approach to the traditional Maillard process conducted at elevated temperatures in creating conjugated gluten hydrolysates with enhanced bioactivities. © 2014 Elsevier Ltd.

The structural patterns formed by molecular self-assembly at surfaces are usually controlled by the relative strengths of the intermolecular and molecule-substrate interactions. An additional steering effect is present when the substrate can easily reconstruct upon molecular adsorption, which therefore drives a self-templating effect on the metal support. This is here demonstrated for the model case of Fephthalocyanine molecules adsorbed on the Au(110) surface. Scanning tunneling microscopy shows that molecular adsorption promotes a local (1 x 5) surface reconstruction, which drives the assembly of molecular chains along the [1 (1) over bar0] direction. The order and periodicity of the molecular assemblies are determined with low energy electron diffraction patterns. Density functional theory calculations reveal the energetic origins of the molecule-driven substrate reconstruction. Since the function of molecular overlayers at surfaces is strongly correlated to their structure, these results have implications in the design of new metal/molecular interfaces.

A mixture of novel glycopeptides from glycosylation between cold water fish skin gelatin hydrolysates and glucosamine (GlcN) via transglutaminase (TGase), as well as glycation between fish gelatin hydrolysate and GlcN were identified by their pattern of molecular distribution using MALDI-TOF-MS. Glycated/ glycosylated hydrolysates showed superior bioactivity to their original hydrolysates. Alcalase-derived fish skin gelatin hydrolysate glycosylated with GlcN in the presence of TGase at 25 °C (FAT25) possessed antioxidant activity when tested in a linoleic acid oxidation system, when measured according to its 2,2- diphenyl-1-picrylhydrazyl (DPPH) scavenging activity and when tested at the cellular level with human hepatocarcinoma (HepG2) cells as target cells. In addition, Alcalase-derived glycosylated hydrolysates showed specificity toward the inhibition of Escherichia coli (E. coli). The Flavourzyme-derived glycopeptides prepared at 37 °C (FFC37 and FFT37) showed better DPPH scavenging activity than their native hydrolysates. The glycated Flavourzyme-derived hydrolysates were found to act as potential antimicrobial agents when incubated with E. coli and Bacillus subtilis. © 2013 Elsevier Ltd. All rights reserved.

Iron-phthalocyanine molecules deposited on the Au(110) reconstructed channels assemble into one-dimensional molecular chains, whose spatial distribution evolves into different structural phases at increasing molecular density. The plasticity of the Au channels first induces an ordered phase with a 5×5 symmetry, followed by a second long-range ordered structure composed by denser chains with a 5×7 periodicity with respect to the bare Au surface, as observed in the low-energy electron-diffraction (LEED) and grazing incidence X-ray diffraction (GIXRD) patterns. The geometry of the FePc molecular assemblies in the Au nanorails is determined by scanning tunneling microscopy (STM). For the 5×7 phases, the GIXRD analysis identifies a "4-3" rows profile along the [001] direction in the Au surface and an on-top FePc adsorption site, further confirmed by density functional theory (DFT) calculations. The latter also reveals the electronic mixing of the interface states. The chain assembly is driven by the molecule-molecule interaction and the chains interact with the Au nanorails via the central metal atom, while the chain-chain distance in the different structural phases is primarily driven by the plasticity of the Au surface.

Iron-phthalocyanine (FePc) molecules deposited on the Au(110) surface self-organize in ordered chains driven by the reconstructed Au channels. The interaction process induces a rehybridization of the electronic states localized on the central metal atom, breaking the 4-fold symmetry of the molecular orbitals of the FePc molecules. The molecular adsorption is controlled by a symmetry-determined mixing between the electronic states of the Fe metal center and of the Au substrate, as deduced by photoemission and absorption spectroscopy exploiting light polarization. DFT calculations rationalize this mixing of the Fe and Au states on the basis of symmetry arguments. The calculated electronic structure reproduces the main experimental spectral features, which are associated to a distorted molecular structure displaying a trigonal bipyramidal geometry of the ligands around the metal center.

A single layer of bismuth deposited on the Cu(100) surface forms long range ordered structural phases at various Bi density. A highly ordered c(2 x 2) reconstruction is accomplished at 0.5 ML, further Bi deposition induces a c(9square root of 2 x square root of 2)R45 degrees structure and a subsequent p(10 x 10) phase related to the formation of regular dislocations arrays. The transition from a c(2 x 2) superstructure to the c(9square root of 2 x square root of 2)R45 degrees phase is accompanied by a sudden decrease in the work function. Photoemission measurements reveal that the Bi induced states close to the Fermi level, associated to the c(2 x 2) phase, are strongly quenched when the arrays of dislocations are formed, while at higher binding energies, they undergo an energy shift probably due to a confinement effect. The low-energy single particle excitations and the electron dispersion of the Bi induced states of the c(2 x 2) phase are compared to the electronic states deduced by theoretical band structure obtained by ab initio calculation performed within the embedding method applied to a realistic semi-infinite system.

A single layer (SL) of pentacene molecules deposited on the Cu(119) surface and on an organic self-assembled monolayer (SAM) has been investigated by near-edge x-ray absorption fine structure (NEXAFS) at the C $K$ edge, and by photoemission at the $\mathrm{C}\phantom{\rule{0.2em}{0ex}}1s$ core level. The lowest unoccupied molecular orbitals (LUMOs) of the pentacene SL on the SAM are basically unaffected with respect to that of pentacene in the gas phase, indicating a weak interaction of pentacene with the SAM, while a strong redistribution of the LUMO-related final states is observed when the molecules are deposited on the Cu(119) substrate, sign of an electronic mixing between molecular and metal electronic states, in agreement with recent theoretical predictions. The strong dichroic response of the NEXAFS signal indicates upstanding pentacene molecules oriented 16\ifmmode^\circ\else\textdegree\fi{} off normal for the organic-organic heterostructure. The rehybridization of pentacene orbitals with Cu states at the pentacene/Cu interface hinders an accurate determination of the molecule orientation, which is, however, compatible with molecules lying flat on the Cu(119) terraces.

We have investigated the structural and electronic properties of a pentacene film (similar to 2 nm) grown on the Cu(1 1 9) substrate using scanning tunneling microscopy (STM) and synchrotron based angle-resolved UV photoelectron spectroscopy at room temperature. STM images indicate an ordered superstructure of pentacene molecules lying almost flat with respect to the substrate. From angular-resolved photoemission spectra, we have observed an energy-band dispersion of about 100 meV for the highest occupied molecular orbital in the direction perpendicular to the pentacene surface. (C) 2007 Elsevier B.V. All rights reserved.

There is an ever-growing interest in the use of vegetable diets in animal nutrition with the aim of improving food safety to defend and promote the health of consumers. The dietary use of linseed (whole seed or oil) in animal feeding has been proposed by many authors to obtain meat with raised PUFA, mainly alpha-linolenic acid (C18:3 n-3) (Enser, 1999; Matthews et al., 2000; Riley et al., 2000; Rey et al., 2001). However, increasing amounts of PUFA could impair the shelf life of meat products by increasing their susceptibility to lipid oxidation during storage and further processing (Morrissey et al., 1998). A study was conducted to investigate the effects of the dietary inclusion of whole linseed and dehydrated lucerne meal (DLM) on some functional traits and on the susceptibility to lipid oxidation of rabbit meat.