Tunable Wide‐Bandgap Monohalide Perovskites

Herein the mechanochemical synthesis of inorganic as well as hybrid organic-inorganic monohalide perovskites with tunable bandgaps is reported. It is shown that the bandgap bowing known for iodide mixed Sn-Pb perovskites is also present in the pure bromide analogous. This results in technologically very interesting materials with bandgaps in the range of 1.7-1.9 eV. Similar bandgap perovskites are typically achieved by mixing two halides that are prone to segregate over time. This limits the achievable open circuit voltage. For monohalide perovskites this problem is eliminated, making these materials especially promising wide bandgap absorbers for tandem solar cells

The ThomX project status

Work supported by the French Agence Nationale de la recherche as part of the program EQUIPEX under reference ANR-10-EQPX-51, the Ile de France region, CNRS-IN2P3 and Université Paris Sud XI - http://accelconf.web.cern.ch/AccelConf/IPAC2014/papers/wepro052.pdfA collaboration of seven research institutes and an industry has been set up for the ThomX project, a compact Compton Backscattering Source (CBS) based in Orsay - France. After a period of study and definition of the machine performance, a full description of all the systems has been provided. The infrastructure work has been started and the main systems are in the call for tender phase. In this paper we will illustrate the definitive machine parameters and components characteristics. We will also update the results of the different technical and experimental activities on optical resonators, RF power supplies and on the electron gun

Activité antifongique des huiles essentielles de Thymus bleicherianus Pomel et Thymus capitatus (L.) Hoffm. & Link contre les champignons de pourriture du bois d'oeuvre

Antifungal activity of the Thymus bleicherianus Pomel and Thymus capitatus (L.) Hoffm. & Link essential oils againstwood-decay fungi. Essential oils and their constituents have a long history of applications as antimicrobial agents, but theiruse as wood preservatives has rarely been reported. This study deals with the antifungal activity of two medicinal and aromaticplants essential oils of the Moroccan flora against four wood-decay fungi, in order to find new bioactive natural products. Thechemical composition of essential oils extracted by hydrodistillation from the aerial parts of Thymus bleicherianus Pomel andThymus capitatus (L.) Hoffm. & Link was analyzed by GC and GC-MS. The major components of T. bleicherianus oil wereα-terpinene (42.2%) and thymol (23.9%). Carvacrol (70.92%) was the predominant constituent in the essence of T. capitatus.Minimal inhibitory concentrations of the essential oils added to malt agar medium in defined concentrations were determinedby a screening test with the agar dilution method. The oils, object of the survey, showed a strong antifungal activity againstall tested fungi

Composition chimique et activité antimicrobienne des huiles essentielles de Thymus algeriensis Boiss. & Reut. et Thymus ciliatus (Desf.) Benth. du Maroc

Chemical composition and antimicrobial activity of the Thymus algeriensis Boiss. & Reut. and Thymus ciliatus (Desf.) Benth. essential oils of Morocco. The aim of this work is to study the chemical composition and antibacterial and antifungal activity of essential oils of Thymus algeriensis Boiss. & Reut. and Thymus ciliatus (Desf.) Benth. of Morocco against seven microorganisms. The essential oils of T. ciliatus are characterized by the presence of thymol (44.2%), β-E-ocimene (25.8%) and α-terpinene (12.3%) as principal chemical components. The essential oils of T. algeriensis are formed mainly by camphor (27.7%) and α-pinene (20.5%). The oil of T. ciliatus showed a strong antibacterial and antifungal activity against all tested bacteria and fungi. This bioactivity is due mainly to the richness of this essential oil in thymol known for its effectiveness against the microbial agents

SIMULATIONS AND RF MEASUREMENTS OF THE FUNDAMENTAL AND HIGHER ORDER MODES OF THE THOMX 500 MHz CAVITY*

The RF system of the ThomX storage ring consists in a 500 MHz single cell copper cavity of the ELETTRA type, powered with a 50 kW CW solid state amplifier, and the associated Low Level RF feedback and control loops. The low operating energy of 50–70 MeV makes the impedances of the cavity higher order modes (HOMs) particularly critical for the beam stability. Their parasitic effects on the beam can be cured by HOM frequency shifting techniques, based on a fine temperature tuning and a dedicated plunger. A typical cavity temperature stability of ± 0.05°C within a range from 35 up to 80 °C can be achieved by a precise control of its water cooling temperature. On the other hand, the tuning of the cavity fundamental mode is achieved by changing its axial length by means of a mechanical tuner. In order to insure a fine control of the HOM frequencies, a good knowledge of their characteristics is mandatory. The main parameters of the fundamental and of the HOMs up to 4 GHz have been calculated using the HFSS and CST MWS codes. Preliminary measurements results have been obtained and show a good agreement with the simulations

Novel thin-film solid nanocomposite electrolyte for lithium-Ion batteries by combined MLD and ALD

This work reports on the first thin-film solid nanocomposite electrolyte (NCE) for lithium-ion batteries made by combining two gas-phase deposition techniques, molecular layer deposition (MLD) and atomic layer deposition (ALD). The advantage of using these techniques for the fabrication of NCEs comes from the ease of integration in thin-film batteries and the possibility to alter the properties of the oxide matrix and of the Li-compound independently. Moreover, the mesoporous oxide matrix based on an MLD and etching process, provides uniform interfaces with continuous conduction paths. An enhancement in Li-ion conductivity of two orders of magnitude, compared to the pure Li-compound, is obtained for an NCE consisting of a mesoporous Al2O3 matrix filled with Li2CO3. The impact of the oxide matrix on the resulting NCE Li-ion conductivity is considerable, showing four orders of magnitude difference between silica and alumina. Finally, integration of the NCE in a thin-film solid-state battery stack utilizing a Li-metal anode is demonstrated with good coulombic efficiency over a broad temperature range. The current findings and approach can expand the possibilities for development of novel thin-film solid-state electrolytes

Novel Thin-Film Solid Nanocomposite Electrolyte for Lithium-Ion Batteries by Combined MLD and ALD

status: publishe