Hydrogen bonding in substituted nitroanilines : isolated nets in 1,3-diamino-4-nitrobenzene and continuously interwoven nets in 3,5-dinitroaniline

Peer reviewedPublisher PD

The electrical characterization and response to hydrogen of Schottky diodes with a resistive metal electrode—rectifying an oversight in Schottky diode investigation

International audienceSchottky barrier structures with a resistive metal electrode are examined using the 4-point probe method where the probes are connected to the metal electrode only. The observation of a significant decrease in resistance with increasing temperature (over a range of ~ 100K) in the diode resistance-temperature (R D-T) characteristic is considered due to charge carrier confinement to the metal electrode at low temperature (high resistance), with the semiconductor progressively opening up as a parallel current carrying channel (low resistance) with increasing temperature due to increasing thermionic emission across the barrier. A simple model is constructed, based on thermionic emission at quasi-zero bias, that generates good fits to the experimental data. The negative differential resistance (NDR) region in the R D -T characteristic is a general effect and is demonstrated across a broad temperature range for a variety of Schottky structures grown on Si-, GaAs- and InP- substrates. In addition the NDR effect is harnessed in micro-scaled Pd/n-InP devices for the detection of low levels of hydrogen in an ambient atmosphere of nitrogen

Insights into the room temperature magnetism of ZnO/Co3O4 mixtures

The origin of room temperature (RT) ferromagneticlike behavior in ZnO-based diluted magnetic semiconductors is still an unclear topic. The present work concentrates on the appearance of RT magnetic moments in just mixed ZnO/Co3O4 mixtures without thermal treatment. In this study, it is shown that the magnetism seems to be related to surface reduction of the Co3O4 nanoparticles, in which, an antiferromagnetic Co3O4 nanoparticle (core) is surrounded by a CoO-like shell. This singular superficial magnetism has also been found in other mixtures with semiconductors such as TiO2 and insulators such as Al2O3

The El Guijo Pluton: petrology, geochemistry, age and relation to others rocks of Los Pedroches batholith

[Resumen] El plutón de El Guijo es uno de los plutones ácidos circunscritos, intrusivos en las granodioritas que constituyen los tercios central y occidental del batolito de Los Pedroches. Con forma subelíptica, presenta una zonación centrípeta que va desde facies marginales graníticas biotíticas (localmente con microadamellitas porfídicas), marcadamente porfídicas, hasta facies centrales de leucogranitos cordieríticos (± moscovita). Geoquímicamente, las rocas de este plutón definen una asociación peraluminosa, con evolución netamente calcoalcalina. Se presentan los resultados de una datación (Rb-SR, roca total) que definen una isocrona de 300 ± 6 Ma, con (87 Sr/86 Sr) o de 0.704. Finalmente, se discuten sus relaciones y significado en el contexto general del batolito de Los Pedroches.[Abstract] The El Guijo pluton belongs to a group of centred, acidic plutons which intrude the ranodiorites making the most part of the Pedroches Batholith central and western thirds. It has a sub-elliptical shape and shows a centripetal zonation which ranges between marginal, biotite-bearing porphyritic granitic facÍes (locally intruding porphyritic micro-adamellites) and central cordierite -bearing leucogranites (± muscovite). They collectively define a peraluminous association with a neat calcalkaline evolution. The results of a Rb-Sr whole-rock study are presented. These define a 300 ±6 Ma age isochron with (87 Sr/86 Sr) o = 0.704. Finally, its relationships with, and its significance in the context of the overall Pedroches Batholith are discused

Experimental setup and procedure for the measurement of the 7Be(n,p)7Li reaction at n_TOF

Following the completion of the second neutron beam line and the related experimental area (EAR2) at the n_TOF spallation neutron source at CERN, several experiments were planned and performed. The high instantaneous neutron flux available in EAR2 allows to investigate neutron induced reactions with charged particles in the exit channel even employing targets made out of small amounts of short-lived radioactive isotopes. After the successful measurement of the 7Be(n,) cross section, the 7Be(n,p)7Li reaction was studied in order to provide still missing cross section data of relevance for Big Bang Nucleosynthesis (BBN), in an attempt to find a solution to the cosmological Lithium abundance problem. This paper describes the experimental setup employed in such a measurement and its characterization.Séptimo Programa Marco de la Comunidad Europea de la Energía Atómica (Euratom)-Proyecto CHANDA (No. 605203)Narodowe Centrum Nauki (NCN)-UMO-2012/04/M/ST2/00700-UMO-2016/22/M/ST2/00183Croatian Science Foundation-HRZZ 168

Description of analyzing power and (p,n) reaction by a global dispersive coupled-channel optical model potential

A global dispersive coupled-channel optical model potential is used to analyze the proton elastic/inelastic analyzing power data and (p,n) data in order to investigate the prediction power of this potential. The numerical calculations show good agreement with available experimental data for proton elastic data and overall agreement for proton inelastic data. The results also showed that present global potential is approximately Lane-consistent, and can predict well the (p,n) cross sections

A K=3 two-quasiparticle isomer in 98^{98}Sr

The decay of on-line mass-separated 98 Rb to 98 Sr is studied by γ spectroscopy. The revised decay scheme adds further evidence of the coexistence of very different shapes in 98 Sr . A set of levels is proposed to originate from particle-hole pair excitations across the Z = 40 spherical gap in analogy with 96 Sr . A deformed K = 3 band with probable even parity is built on a 7.1-ns isomer at 1838 keV. It is interpreted as a two-quasineutron excitation in accordance with a quantum Monte Carlo pairing calculation based on a deformed shell model. Configurations of the calculated lowest-lying two-quasiparticle levels confirm the importance of the [404]9/2 neutron orbital at the largest deformations in the neutron-rich A ≃ 100 region

Interface double-exchange ferromagnetism in the Mn-Zn-O system: New class of biphase magnetism

In this Letter, we experimentally show that the room temperature ferromagnetism in the Mn-Zn-O system recently observed is associated with the coexistence of Mn^(3+) and Mn^(4+) via a double-exchange mechanism. The presence of the ZnO around MnO_2 modifies the kinetics of MnO_2 →Mn_2O_3 reduction and favors the coexistence of both Mn oxidation states. The ferromagnetic phase is associated with the interface formed at the Zn diffusion front into Mn oxide, corroborated by preparing thin film multilayers that exhibit saturation magnetization 2 orders of magnitude higher than bulk samples

Overlap and diversity in antimicrobial peptide databases: Compiling a non-redundant set of sequences

Motivation: The large variety of antimicrobial peptide (AMP) databases developed to date are characterized by a substantial overlap of data and similarity of sequences. Our goals are to analyze the levels of redundancy for all available AMP databases and use this information to build a new nonredundant sequence database. For this purpose, a new software tool is introduced. Results: A comparative study of 25 AMP databases reveals the overlap and diversity among them and the internal diversity within each database. The overlap analysis shows that only one database (Peptaibol) contains exclusive data, not present in any other, whereas all sequences in the LAMP-Patent database are included in CAMP-Patent. However, the majority of databases have their own set of unique sequences, as well as some overlap with other databases. The complete set of non-duplicate sequences comprises 16 990 cases, which is almost half of the total number of reported peptides. On the other hand, the diversity analysis identifies the most and least diverse databases and proves that all databases exhibit some level of redundancy. Finally, we present a new parallel-free software, named Dover Analyzer, developed to compute the overlap and diversity between any number of databases and compile a set of non-redundant sequences. These results are useful for selecting or building a suitable representative set of AMPs, according to specific needs. © The Author 2015. Published by Oxford University Press. All rights reserved.Antimicrobial Cationic Peptide