Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

Thermal conductivity of carbon nanotubes and graphene in epoxy nanofluids and nanocomposites

Abstract We employed an easy and direct method to measure the thermal conductivity of epoxy in the liquid (nanofluid) and solid (nanocomposite) states using both rodlike and platelet-like carbon-based nanostructures. Comparing the experimental results with the theoretical model, an anomalous enhancement was obtained with multiwall carbon nanotubes, probably due to their layered structure and lowest surface resistance. Puzzling results for functionalized graphene sheet nanocomposites suggest that phonon coupling of the vibrational modes of the graphene and of the polymeric matrix plays a dominant role on the thermal conductivities of the liquid and solid states. PACS: 74.25.fc; 81.05.Qk; 81.07.Pr.The work was supported by the Spanish Ministry of Science and Innovation (MICINN) under project MAT 2010-18749. MMG thanks the CSIC for a JAE-Pre grant.Peer Reviewe

Optical properties of TiO2 thin films prepared by Sol Gel method

International audienceTitanium dioxide is currently the focus of intensive research because of their interesting chemical, electrical and optical properties. In this work, TiO2 thin films were prepared by sol gel method, and have been deposited by spin coating technique onto glass substrates (3–TiO2/ glass). In this work, we report the effect of the spin speed (2900, 3200 and 4900 rpm) on different optical properties of the films. The samples were characterized by means of Raman spectroscopy, hall measurement and UV-Visible spectrophotometer. The transmission spectra of titanium dioxide thin films indicate that there are two parts, the first is transparent in the visible wavelength spectrum region and the second is opaque in the UV ranges. We found that the transmission curves and the calculated optical band gap increase when thespin speed increases. The Raman spectra have shown the Anatase phase

Development of a Lycopodium powder-based superhydrophobic nanofiber membrane suitable for desalination

2023 Acuerdos transformativos CRUEA biobased, green, inexpensive additive, Lycopodium particles, which are spores of the “Lycopodium clavatum” plant, were incorporated in the poly(vinylidene fluoride) PVDF electrospun nanofiber membranes (ENMs) for desalination by direct contact membrane distillation (DCMD). Superhydrophobic ENMs were prepared using this additive (PVDF-ENMs-Lyc). Thanks to their morphological structure and their prominent surface superhydrophobicity (anti-wetting) character, the resulting PVDF-ENMs-Lyc exhibited an improved liquid entry pressure (LEP), a high void volume fraction (greater than 87.2%), a good salt rejection factor (greater than 99.93%) and a reasonably high permeate flux (greater than 51.76 kg⋅m− 2 ⋅h− 1 ) at 80 ◦C, which are of great practical importance for water desalination by DCMD. The optimum membrane prepared with 3 wt% Lycopodium in the dope solution demonstrated a stable permeate flux of 52.4 ± 0.6 kg⋅m− 2 ⋅h− 1 with an electrical conductivity around 4.76 ± 0.46 μS/cm (NaCl rejection factor of 99.998 ± 0.036%) during 25 h DCMD desalination experiment using 35 g/L NaCl aqueous solution (similar to seawater concentration). The presented results pave the way for superhydrophobic nanofibrous membrane engineering suitable for membrane contactors by electrospinning in a single step without surfactants, organic additives, or chemical post-treatments, just by the incorporation of a green additive like LycopodiumMinisterio de Ciencia, Innovación y Universidades (España)Depto. de Estructura de la Materia, Física Térmica y ElectrónicaTRUEpu

The first reintroduction project for mhorr gazelle (Nanger dama mhorr) into the wild: Knowledge and experience gained to support future conservation actions

Reintroductions continue to be an important conservation action for endangered species. Until this, all reintroduction projects for Mhorr gazelle (Nanger dama mhorr) had remained at the stage where the animals live in fenced protected areas of different sizes. This study describes the first experience of reintroduction of a group of 24 Mhorr gazelle into the wild in the Safia Reserve, in Southern Morocco. The reintroduction was carried out in two phases: in the first one, the entire group was released; then, after an unexpected dogs attack event, part of them were kept safe until this problem was solved. Seven of the gazelles were monitored with telemetry collars, providing previously unavailable data on time allocation, daily rhythm of activity and social organization for the species in the wild. In addition, post-release movements revealed three patterns: during the first few days after release, small daily movements (average 2.78 km) close to the fence, followed by long-distance exploratory movements (up to 50 km) until establish territories; and finally, daily movements between established territories (average 8.39 km). Exceptional long distances (>50 km/day) were traveled after a poaching event. The study has also revealed the ability of the species to select and settle territories in favorable areas, after being kept for generations under captive or semi-captive conditions. However, their inability to recognize predators was demonstrated in an unexpected attack by dogs, resulting in the death of seven released gazelles. This mortality following the dog attack was favored, in part, because the released gazelle remained close to the fence, and therefore suggests that the release procedure should be revised, especially when there are predators in the release site. This study has confirmed that dogs as predators and poaching continue to be the main threat to reintroduction projects in Southern Morocco.This project has been funded by UNESCO/MaB (no 4500261532), HCEFLCD and the National Spanish Research Council (CSIC OTT 2005X0269). Emilio Rodriguez Caballero would like to acknowledge the Spanish Ministry for Economy and Competitiveness for the Juan de la Cierva-Incorporación grant (IJCI-2016-29274) and the University of Almeria for the Hipatia-UAL postdoctoral fellowshi