Publications associées à Ring system

Metallicity Distribution Functions of 13 Ultra-faint Dwarf Galaxy Candidates from Hubble Space Telescope Narrowband Imaging

We present uniformly measured stellar metallicities of 463 stars in 13 Milky Way (MW) ultra-faint dwarf galaxies (UFDs; M-V = -7.1 to -0.8) using narrowband CaHK (F395N) imaging taken with the Hubble Space Telescope. This represents the largest homogeneous ...

Iop Publishing Ltd2023

DFT plus U-type functional derived to explicitly address the flat plane condition

Edward Baxter Linscott

A DFT+U-type corrective functional is derived from first principles to enforce the flat plane condition on localized subspaces, thus dispensing with the need for an ad hoc derivation from the Hubbard model. Small, molecular test systems at the dissociated ...

AMER PHYSICAL SOC2023

Semipinacol Rearrangement of Cyclopropenylcarbinols for the Synthesis of Highly Substituted Cyclopropanes

Jérôme Waser, Vladyslav Smyrnov

An electrophile-induced semipinacol rearrangement of cyclopropenylcarbinols is reported. This transformation gives access to various polyfunctionalized cyclopropanes under mild metal-free conditions. The scope of the reaction includes iodine, sulfur and se ...

2023

Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST

Michaela Hirschmann

We present a search for extremely red, dust-obscured, z > 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin(2) of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W-F444W (simil ...

Iop Publishing Ltd2023

Synthesis of polycyclic aminal heterocycles via decarboxylative cyclisation of dipeptide derivatives

Jérôme Waser, Eliott Hugo Joran Le Du, Emma Gabrielle Louise Robert

An oxidative-decarboxylative intramolecular cyclisation of dipeptide derivatives is reported. This transformation is promoted by phenyl iodine(iii) diacetate (PIDA) in combination with BF3 center dot OEt2. The reaction gives access to a variety of valuable ...

Royal Society of Chemistry2022

TOCOSMO VIII. A key test of systematics in the hierarchical method of time-delay cosmography

Frédéric Courbin

The largest source of systematic errors in the time-delay cosmography method likely arises from the lens model mass distribution, where an inaccurate choice of model could in principle bias the value of H-0. A Bayesian hierarchical framework has been propo ...

EDP SCIENCES S A2022

Three-membered cyclic digermylenes stabilised by an N-heterocyclic carbene dagger

Zhaowen Dong

Treatment of potassium salts of silole dianions with donor stabilised germanium dichlorides gave the anticipated silagermafulvenylidenes R2Si = Ge(Do) (R2Si = 1-silacyclopentadiendiyl, Do = N-heterocyclic carbene (NHC)) only as transient intermediates in a ...

2021

Arbitrarily high time bandwidth performance in a nonreciprocal optical resonator with broken time invariance

Camille Sophie Brès, Hatice Altug, Davide Grassani, Simon Julien Fabbri, Ivan Cardea, Kosmas Tsakmakidis

Most present-day resonant systems, throughout physics and engineering, are characterized by a strict time-reversal symmetry between the rates of energy coupled in and out of the system, which leads to a trade-off between how long a wave can be stored in th ...

Nature Research2020

Heterotetracenes: Flexible Synthesis and in Silico Assessment of the Hole Transport Properties

Jérôme Waser, Kevin Sivula, Anne-Clémence Corminboeuf, Felipe Andres Saenz Padilla, Xavier Adrian Jeanbourquin, Ganna Gryn'ova, Yifan Li

Thienoacenes and furoacenes are among the most frequent molecular units found in organic materials. The efficient synthesis of morphologically different heteroacenes and the rapid determination of their solid-state and electronic properties are still chall ...

2017

Structure of Herbig AeBe Disks at the milliarcsecond Scale—A Statistical Survey in the H Band Using PIONIER-VLTI

Ferréol Arnaud Marie Soulez

Context. It is now generally accepted that the near-infrared excess of Herbig AeBe stars originates in the dust of a circumstellar disk. Aims. The aims of this article are to infer the radial and vertical structure of these disks at scales of order 1 au, a ...

ESO2017

Reaction between propargyl radical and 1,3-butadiene to form five to seven membered rings. Theoretical study

Daniela Trogolo

Propargyl radical addition to 1,3-butadiene seems to be a promising channel to form 5-, 6-, and 7-membered rings. These are important steps in the growth of polycyclic aromatic hydrocarbons and soot platelets. The reaction mechanism, involving 97 intermedi ...

Elsevier Science Inc2016

Lewis acid Catalyzed Annulations of Donor-Acceptor Aminocyclopropanes and Aminocyclobutanes

Sophie Lucie Racine

Organic molecules are indispensable have greatly contributed to the confort of our modern life. Nevertheless, humanity is facing now new challenges such as environmental issues and emerging drug resistances. In order to solve these major concerns, chemists ...

EPFL2016

Catalytic C-C Bond Activations via Oxidative Addition to Transition Metals

Nicolai Cramer, Laetitia Marie Mélanie Souillart

Selective cleavages of carbon-carbon bonds catalyzed by transition-metal complexes have been shown to be increasingly versatile tools for organic synthesis allowing for complementary synthetic strategies. Numerous examples of transition-metal catalyzed C-C ...

Amer Chemical Soc2015

Enantioselective palladium(0)-catalyzed intramolecular cyclopropane functionalization: access to dihydroquinolones, dihydroisoquinolones and the BMS-791325 ring system

Nicolai Cramer, Tanguy Jean Daniel Saget, Pavel Alexandrovich Donets, Julia Pedroni

Taddol-based phosphoramidite ligands enable enantioselective palladium(0)-catalyzed C-H arylation of cyclopropanes. The cyclized products are obtained in high yields and enantioselectivities. The reported method provides efficient access to a broad range o ...

Royal Soc Chemistry2015

Planck 2013 results. VII. HFI time response and beams

Julien Lesgourgues, Fabio Finelli

This paper characterizes the effective beams, the effective beam window functions and the associated errors for the Planck High Frequency Instrument (HFI) detectors. The effective beam is the angular response including the effect of the optics, detectors, ...

Edp Sciences S A2014

Double Concentric Autofluorescence Ring in NR2E3-p.G56R-Linked Autosomal Dominant Retinitis Pigmentosa

Pascal Escher

PURPOSE. We reported an unusual appearance of fundus autofluorescence (FAF) associated with NR2E3-p.G56R-linked autosomal dominant retinitis pigmentosa (ADRP). METHODS. Patients were enrolled among three generations in a Swiss family. Molecular diagnosis i ...

Assoc Research Vision Ophthalmology Inc2012

Preparation of 5-Membered Rings via Radical Addition-Translocation-Cyclization (RATC) Processes Mediated by Diethyl Thiophosphites

Philippe Renaud, Kurt Schenk

A practical method for the formation of thiophosphonates bearing functionalized monocyclic, fused bicyclic and spirocyclic residues is presented. The procedure requires the easily available terminal alkynes as starting materials as well as commercially and ...

Wiley2011

The CORALIE survey for southern extrasolar planets XVI. Discovery of a planetary system around HD 147018 and of two long period and massive planets orbiting HD 171238 and HD 204313

We report the detection of a double planetary system around HD 140718 as well as the discovery of two long period and massive planets orbiting HD 171238 and HD 204313. Those discoveries were made with the CORALIE Echelle spectrograph mounted on the 1.2-m E ...

2010

Connecting C-19 Norditerpenoids to C-20 Diterpenes: Total Syntheses of 6-Hydroxy-5,6-dehydrosugiol, 6-Hydroxysugiol, and Taiwaniaquinone H, and Formal Synthesis of Dichroanone

Rosario Scopelliti, Karl Gademann

Oxidation of the B-ring of abietane derivatives by Sharpless dihydroxylation gave the natural products 6-hydroxy-5,6-dehydrosugiol and 6-hydroxysugiol. Moreover, further oxidation gave a hydroxy dione derivative that provides a synthetic entry into the C-1 ...

2010

Open-loop control of compressible afterbody flows using adjoint methods

Philippe Meliga

The flow past an axisymmetric body is generically unstable to a steady and a time-periodic global instability, the latter being thought to lead the low-frequency unsteadiness of the wake even at larger Reynolds numbers. The present paper examines how the g ...

2010