Comparing the Performance of Nb2O5 Composites with Reduced Graphene Oxide and Amorphous Carbon in Li‐ and Na‐Ion Electrochemical Storage Devices

Two‐dimensional (2D) reduced graphene oxide (rGO) is often combined with metal oxides for energy‐storage applications, owing to its unique properties. Here, we compare the electrochemical performance of Nb2O5‐rGO and amorphous carbon‐coated‐Nb2O5 composites, synthesized in similar conditions. The composite made of Nb2O5 and amorphous carbon (using 1,3,5‐triphenylbenzene as carbon source) outperforms the Nb2O5‐rGO counterpart as a high rate anode electrode material in Li‐ion and Na‐ion half‐cells and hybrid supercapacitors, delivering specific capacities of 134 mAh g−1 at 25 C against 98 mAh g−1 for the rGO‐based composite (in Li electrolyte) and 125 mAh g−1 at 20 C against 98 mAh g−1 (in Na electrolyte). The organic molecules, which are the precursor of the amorphous carbon, control the size and coat the metal oxide particles more efficiently, leading to more extensive carbon‐oxide contacts, which benefits the energy‐storage performance.Peer Reviewe

Exploiting the Condensation Reactions of Acetophenone to Engineer Carbon-Encapsulated Nb2O5 Nanocrystals for High-Performance Li and Na Energy Storage Systems

Efficient synthetic methods to produce high‐performance electrode‐active materials are crucial for developing energy storage devices for large‐scale applications, such as hybrid supercapacitors (HSCs). Here, an effective approach to obtain controllable carbon‐encapsulated T‐Nb2O5 nanocrystals (NCs) is presented, based on the solvothermal treatment of NbCl5 in acetophenone. Two separate condensation reactions of acetophenone generate an intimate and homogeneous mixture of Nb2O5 particles and 1,3,5‐triphenylbenzene (TPB), which acts as a unique carbon precursor. The electrochemical performance of the resulting composites as anode electrode materials can be tuned by varying the Nb2O5/TPB ratio. Remarkable performances are achieved for Li‐ion and Na‐ion energy storage systems at high charge–discharge rates (specific capacities of ≈90 mAh g−1 at 100 C rate for lithium and ≈125 mAh g−1 at 20 C for sodium). High energy and power densities are also achieved with Li‐ and Na‐ion HSC devices constructed by using the Nb2O5/C composites as anode and activated carbon (YPF‐50) as cathode, demonstrating the excellent electrochemical properties of the materials synthesized with this approach.Peer Reviewe

Impact of the HIV-1 env Genetic Context outside HR1–HR2 on Resistance to the Fusion Inhibitor Enfuvirtide and Viral Infectivity in Clinical Isolates

Resistance mutations to the HIV-1 fusion inhibitor enfuvirtide emerge mainly within the drug's target region, HR1, and compensatory mutations have been described within HR2. The surrounding envelope (env) genetic context might also contribute to resistance, although to what extent and through which determinants remains elusive. To quantify the direct role of the env context in resistance to enfuvirtide and in viral infectivity, we compared enfuvirtide susceptibility and infectivity of recombinant viral pairs harboring the HR1–HR2 region or the full Env ectodomain of longitudinal env clones from 5 heavily treated patients failing enfuvirtide therapy. Prior to enfuvirtide treatment onset, no env carried known resistance mutations and full Env viruses were on average less susceptible than HR1–HR2 recombinants. All escape clones carried at least one of G36D, V38A, N42D and/or N43D/S in HR1, and accordingly, resistance increased 11- to 2800-fold relative to baseline. Resistance of full Env recombinant viruses was similar to resistance of their HR1–HR2 counterpart, indicating that HR1 and HR2 are the main contributors to resistance. Strictly X4 viruses were more resistant than strictly R5 viruses, while dual-tropic Envs featured similar resistance levels irrespective of the coreceptor expressed by the cell line used. Full Env recombinants from all patients gained infectivity under prolonged drug pressure; for HR1–HR2 viruses, infectivity remained steady for 3/5 patients, while for 2/5 patients, gains in infectivity paralleled those of the corresponding full Env recombinants, indicating that the env genetic context accounts mainly for infectivity adjustments. Phylogenetic analyses revealed that quasispecies selection is a step-wise process where selection of enfuvirtide resistance is a dominant factor early during therapy, while increased infectivity is the prominent driver under prolonged therapy

Les instituteurs et l’inspection primaire

Goubard A. Les instituteurs et l’inspection primaire. In: Manuel général de l'instruction primaire : journal hebdomadaire des instituteurs. 60e année, tome 29, 1893. pp. 375-376

Effects of repeated organic amendment applications on soil and crop qualities

WOS:000392711300011Soil application of organic waste products (OWP) favors the increase of soil organic matter (SOM) and biological activity, the recycling of nutrients and crop production, but it may also lead to soil contamination. All these effects may occur simultaneously and must be considered in the evaluation of the practice. Various urban composts and manure have been applied every second year in a long-term field experiment during 15 years. A soil sampling assessing the cumulative residual effects of seven applications was used to compare the impact on soil and crop quality of four OWP: a municipal solid waste compost (MSW), a co-compost of sewage sludge and green waste (GWS), a biowaste compost (BIO) and a farmyard manure (FYM). More than 100 different soil indicators were measured (including organic C, N availability, pH, POlsen, plasticity, microbial biomass, enzymatic activity, trace elements and crop yield) and classified in categories to explain soil functioning including crop production: soil fertility, soil biological activity, soil biodiversity, soil physical stability, soil sanitary status (available and total) and crop productivity. Based on these categories, seven minimum data sets (MDS) were defined using statistical analysis, in order to eliminate overlapping parameters and select significant indicators highlighting the effects of OWP compared with a mineral fertilization. The aim of this study was to evaluate the long-term effects of repeated OWP applications on the seven categories of indicators. The OWP were characterized by different qualities and properties of organic matter (OM), which drove their potential effects after application on cropped soils. The GWS and BIO were the most efficient OWP at increasing SOM content, which was one of the major drivers of the effects

Labeling of fibronectin by fluorescent and paramagnetic nanoprobes for exploring the extracellular matrix: bioconjugate synthesis optimization and biochemical characterizatio

International audienc