An exponential market growth of Li-ion batteries (LIBs) has been observed in the past 20 years; approximately 670,000 tons of LIBs have been sold in 2017 alone. This trend will continue owing to the growing interest of consumers for electric vehicles, recent engagement of car manufacturers to produce them, recent developments in energy storage facilities, and commitment of governments for the electrification of transportation. Although some limited recycling processes were developed earlier after the commercialization of LIBs, these are inadequate in the context of sustainable development.
View Article and Find Full Text PDFDouble-walled carbon nanotubes (DWNTs) present an original coaxial geometry in which the inner wall is naturally protected from the environment by the outer wall. Covalent functionalization is introduced here as an effective approach to investigate DWNT devices. Performed using an aryldiazonium salt, the functionalization is reversible upon thermal annealing and occurs strictly at the surface of the outer wall, leaving the inner wall essentially unaltered by the chemical bonding.
View Article and Find Full Text PDFBackground: Studies have suggested that nonmaternal care (NMC) may either carry risks or be beneficial for children's language development. However, few tested the possibility that NMC may be more or less protective for children with different family backgrounds. This study investigates the role of the family environment, as reflected in the socioeconomic status (SES), in the association between NMC in the first year of life and children's receptive language skills prior to school entry.
View Article and Find Full Text PDFIn this study, we examine, in detail, the synthesis of single wall carbon nanotubes (C-SWNTs) with a plasma torch, using molecular sources for both carbon and catalyst (typically a carbon-containing gas such as ethylene and ferrocene for the metal catalyst). A comparison of the results obtained by Raman spectroscopy, using two different excitation wavelengths, permitted us to evaluate the importance of certain experimental parameters affecting the quality of the samples; these include the growth temperature of the nanotubes, and the temperature gradient between the flame and the oven. We have found that our method provides results that are qualitatively similar to those obtained using arc and laser techniques: C-SWNTs mixed with catalyst nanoparticles and amorphous carbon.
View Article and Find Full Text PDFAutologous saphenous veins, the preferred substitute material for aorto-coronary, femoro-popliteal and femoro-tibial by-pass, are usable in only 70% of individuals in need of such procedures. The development of small diameter substitute arteries is therefore essential to broaden the pool of patients who could benefit from this class of cardiovascular surgery. Existing substitutes, however, present major difficulties and have had limited success.
View Article and Find Full Text PDF