Correction to: EQRAIN: uranium and plutonium interlaboratory exercises from 1997 to 2016—comparison to ITVs-2010

Journal of Radioanalytical and Nuclear Chemistry - In the original publication of the article, the values of u(s), u(r) and ITV for HKED were published incorrectly in Table 6.     

“(Diphosphine)Nickel”‐Catalyzed Negishi Cross‐Coupling: An Experimental and Theoretical Study

The use of a strongly donating “(bis‐dialkylphosphine)Ni” fragment promotes the catalytic coupling of a large range of ArCl and ArZnCl derivatives under mild conditions. Stoichiometric mechanistic investigations and DFT calculations prove that a Ni⁰/Ni^II cycle is operative in this system.     

Comparative Study of Alkali-Cation-Based (Li+, Na+, K+) Electrolytes in Acetonitrile and Alkylcarbonates

The development of a suitable functional electrolyte is urgently required for fast-charging and high-voltage alkali-ion (Li, Na, K) batteries as well as next-generation hybrids supercapacitors. Many recent works focused on an optimal selection of electrolytes for alkali-ion based systems and their electrochemical performance but the understanding of the fundamental aspect that explains their different behaviour is rare. Herein, we report a comparative study of transport properties for LiPF₆, NaPF₆, KPF₆ in acetonitrile (AN) and a binary mixture of ethylene carbonate (EC), dimethyl carbonate (DMC): (EC/DMC : 1/1, weigh) through conductivities, densities and viscosities measurements in wide temperature domain. By application of the Stokes-Einstein, Nernst-Einstein, and Jones Dole equations, the effective ionic solvated radius of cation (r_eff), the ionic dissociation coefficient (α_D) and structuring Jones Dole's parameters (A, B) for salt are calculated and discussed according to solvent or cation nature as a function of temperature. From the results, we demonstrate that better mobility of potassium can be explained by the nature of the ion-ion and ion-solvent interactions due to its polarizability. In the same time, the predominance of triple ions in the case of K⁺, is a disadvantage at high concentration.     

Effect of matrices and additives on phosphorylated and ketodeoxyoctonic acid lipids A analysis by matrix‐assisted laser desorption ionization‐mass spectrometry

Lipid A is a major compound of the outer membrane of gram‐negative bacteria and is a key factor of bacterial virulence. As lipid A's structure differs among bacterial species and varies between strains of the same species, knowing its modifications is essential to understand its implications in the infectious process. To analyze these lipids, matrix‐assisted laser desorption ionization‐mass spectrometry (MALDI‐MS) is a well‐suited method that is fast and efficient. However, there are limitations with the matrix and additives used, such as the suppression of signal or prompt fragmentations that could give a false overview of lipid A composition in biological samples. For a comprehensive analysis of the entire lipid A species present in a sample, we tested 16 matrices and 11 additives on two commercial lipids A. The first commercial one contains single phosphorylation group, and the second contains two phosphorylation and two ketodeoxyoctonic acid (KDO) groups. The lipid A containing KDO groups was essentially detected by the 3‐hydroxypicolinic acid (3‐HPA) matrix, whereas the monophosphorylated lipid A could be detected by 13 matrices out of the 16. We also demonstrated that the signal of diphosphorylated lipid A can be enhanced with the use of additives in the matrix. Our study indicated that the best conditions to obtain a clear signal of both lipids A without prompt fragmentation was the use of 3‐HPA with 10mM trifluoroacetic acid (TFA).     

Iodine(III)-mediated ethoxychlorination of enamides with iron(III) chloride

The combination of (diacetoxyiodo)benzene and iron(III) chloride in ethanol allows the efficient regioselective ethoxychlorination of a broad range of enamides. Mechanistic studies tend to rule out the involvement of free radical species and point towards the implication of a mixed [chloro(ethoxy)iodo]benzene intermediate.     

Cholesteric bonded stationary phases for high-performance liquid chromatography: synthesis, physicochemical characterization, and chromatographic behavior of a phospho–cholesteric bonded support. A new way to mimic drug/membrane interactions?

Among the various methods exploitable to determine the bioavailability of drugs, reversed-phase liquid chromatography (RPLC) appears to be suited to creation of patterns of prediction. In this context a new stationary phase was designed in this work to reproduce, in terms of chemical structure, as accurately as possible, the main elements of cellular membranes; which include phospholipids and cholesterol molecules. An efficient synthetic pathway was developed to prepare ligands that contain a phosphate head, a long alkyl chain chemically bonded to silica, and a cholesteric moiety, in order to mimic both hydrophilic and hydrophobic interactions, and "membrane-like" organization, respectively. The new stationary phase was characterized by Fourier-transform infra red (FTIR) and (1)H-(13)C, (1)H-(31)P, and (1)H-(29)Si cross-polarization magic-angle-spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy. Its chromatographic behavior has been studied by classical classification tests for RPLC columns. Despite its low surface coverage, the material produced exhibits high shape selectivity, possibly due to the organization of the grafted moieties.     

Alkylammonium-based protic ionic liquids. II. Ionic transport and heat-transfer properties: fragility and ionicity rule

The physicochemical characterization of six alkylammonium-based protic ionic liquids (PILs) is presented. These compounds were prepared through a simple and atom-economic neutralization reaction between a tertiary amine and a Br?nsted acid, HX, where X- is HCOO-, CH3COO-, HF2-. The temperature dependency and the effect of added water on properties such as density, viscosity, ionic conductivity, and the thermal comportment of these PILs were measured and investigated. The results allowed us to classify them according to a classical Walden diagram and to appreciate their great "fragility". PILs have applicable perspectives in replacements of conventional inorganic acids for fuel cell devices and thermal transfer fluids.