945 research outputs found
Disordered materials for high-performance lithium-ion batteries: A review
Disordered materials (DMs) have become promising materials in the advancement of lithium-ion batteries (LIBs). Their disordered, open structure is conductive to facilitate efficiency lithium-ion storage. DMs with tunable compositions also possess abundant defects that can interact with Li+, further enhancing their electrochemical performances in LIBs. Yet, revealing the structural origin of the superior electrochemical properties of DM-based LIBs remains a challenge. In this article, we review recent advances in the development of DM-based components for LIBs, such as anodes, cathodes, coating layers, and solid-state electrolytes. We give an overview on the primary methods utilized in preparing and characterizing DMs, while also describing the mechanisms involved in DM synthesis. This review article also addresses the correlation between the structural properties of DMs and their electrochemical performances. Moreover, we elucidate the challenges and future perspectives in the advancement of DM-based LIBs. We outline the key advantages of DMs in enhancing LIB performance over their crystalline counterparts, providing insights for developing superior LIBs through tailored DM development.</p
The extent of violence inflicted on adolescent Aboriginal girls in the Northern Territory
Background:
Australian Aboriginal and Torres Strait Islander women are at very high risk of violence but there is little evidence about the age at which their higher exposure to violence commences. The aim of this study was to investigate violence inflicted on Aboriginal girls during childhood and adolescence, relative to Aboriginal boys and non-Aboriginal girls.
Methods:
This was a retrospective cohort study using de-identified administrative data for NT residents aged 0-17 years. This study used linked hospital and child protection data to investigate hospitalization for injury caused by assault and substantiated child maltreatment involving violence (physical and sexual abuse).
Results:
The incidence of assault hospitalization and substantiated physical/sexual abuse was much higher for Aboriginal than non-Aboriginal adolescents but similar for girls and boys to about age ten, then increased much more for Aboriginal girls than boys. In the 14-17 age-group, assault hospitalization incidence was 125% higher for Aboriginal girls than boys but 56% lower for non-Aboriginal girls than boys. 4.6% of Aboriginal girls were hospitalized (30.9% more than once) for assault between twelfth and eighteenth birthdays, compared to 3.4% of Aboriginal boys and 0.3% of non-Aboriginal girls. The incidence of assault hospitalization during adolescence was over three times higher for Aboriginal children who had substantiated child maltreatment during childhood.
Conclusion:
The very high levels of violence suffered by Aboriginal women commence in the pre-teen years. Non-Aboriginal girls are ‘protected’ from the rising levels of violence that boys experience as they progress through adolescence, but Aboriginal girls are not afforded such protection
An investigation into the depth and time dependent behavior of UV cured 3D ink jet printed objects
An ultra-violet (UV) curable ink jet 3D printed material was characterized by an inverse finite element modeling (IFEM) technique employing a nonlinear viscoelastic–viscoplastic (NVEVP) material constitutive model; this methodology was compared directly with nanoindentation tests. The printed UV cured ink jet material properties were found to be z-depth dependent owing to the sequential layer-by-layer deposition approach. With further post-UV curing, the z-depth dependence was weakened but properties at all depths were influenced by the duration of UV exposure, indicating that none of the materials within the samples had reached full cure during the 3D printing process. Effects due to the proximity of an indentation to the 3D printed material material-sample fixing interface, and the different mounting material, in a test sample were examined by direct 3D finite element simulation and shown to be insignificant for experiments performed at a distance greater than 20 lm from the interface
Effects of Exogenous Cellulase Source on In Vitro Fermentation Characteristics and Methane Production of Crop Straws and Grasses
In vitro fermentation experiments were conducted to investigate the effects of 3 sources of
exogenous cellulase products (EC) at 4 dose rates (DR) (0, 12, 37 and 62 IU/g of DM) on degradation
of forage and methane production by mixed rumen micro-organisms of goats. The maximum gas
production (Vf) of grasses was higher (P<0.001) in Neocallimastix patriciarum (NP) group than those in
Trichoderma reesei (TR) and Trichoderma longibrachiatum (TL) groups. Quadratic increases in dry
matter degradation (DMD) of forage and neutral detergent fiber (NDFD) of straw were observed for all
EC, with optimum DR in the low range. Supplementation of EC originated from TR and NP increased
(P<0.001) DMD of forage compared to that from TL. Addition of EC originated from TR and NP also
decreased pH value, ammonia nitrogen (NH3-N) and methane (CH4) production compared to that from
TL. Quadratic decreases in pH value, NH3-N and CH4 of forage were noted for EC of TR and NP, and
with optimum DR in the low range. For short chain fatty acid, the EC of NP increased total volatile
fatty acid (TVFA) and acetate concentration and the ratio of acetate to propionate of forage compared
with EC of TL and TR, and with optimum DR in the low to medium range. It was concluded that the
source of EC differed in fiber degradation and methane emission, and with optimum DR of TR in the
low range (from 12 to 37 U/g DM) in improving fiber degradation and decreasing methane emission
Geochronological and geochemical constraints on Late Cryogenian to Early Ediacaran magmatic rocks on the northern Tarim Craton:implications for tectonic setting and affinity with Gondwana
The Tarim Craton provides a geologic record of both the fragmentation of the Rodinian supercontinent and the subsequent assembly of Gondwana. However, the timing and interactions of these radically different tectonic processes remain contested. A critical part of this debate revolves around the Late Cryogenian-Ediacaran igneous rocks along the Craton’s northern margin, specifically, whether they record super-plume related Rodinian breakup or Gondwanan orogeny. To address this issue, we present zircon U-Pb-Hf isotopic data and whole rock geochemistry from Late Cryogenian to Early Ediacaran granitoids of the northern Tarim Craton. U-Pb zircon ages reveal three magmatic periods along the northern Tarim margin: ca. 660–640 Ma, 635–625 Ma and 620–600 Ma, associated with small scale felsic and mafic magmas. These granitoids have an A2-type affinity and are enriched in alkalines, but are depleted in Nb, Ta, Sr, P and Ti. Elemental data and generally negative εHf(t) values (−13.96 to 1.65) suggest that they were mainly derived from partial melting of enriched, subduction-modified lithospheric mantle triggered by upwelling of the asthenospheric mantle along the active continental margin of northern Tarim. We suggest that the Tarim Craton travelled as an isolated plate for much of the Late Neoproterozoic, near the outer part of Rodinia and subsequently Gondwana. During this time it was affected by localized and periodic subduction-related intrusion and eruption. However, within the samples of this study, there is no U-Pb-Hf isotopic and whole-rock geochemical evidence to support either super-plume-related rifting (i.e. Rodinian breakup) or Pan-African orogeny (i.e. Gondwanan assembly).</p
Electrical transport studies of quench condensed Bi films at the initial stage of film growth: Structural transition and the possible formation of electron droplets
The electrical transport properties of amorphous Bi films prepared by
sequential quench deposition have been studied in situ. A
superconductor-insulator (S-I) transition was observed as the film was made
increasingly thicker, consistent with previous studies. Unexpected behavior was
found at the initial stage of film growth, a regime not explored in detail
prior to the present work. As the temperature was lowered, a positive
temperature coefficient of resistance (dR/dT > 0) emerged, with the resistance
reaching a minimum before the dR/dT became negative again. This behavior was
accompanied by a non-linear and asymmetric I-V characteristic. As the film
became thicker, conventional variable-range hopping (VRH) was recovered. We
attribute the observed crossover in the electrical transport properties to an
amorphous to granular structural transition. The positive dR/dT found in the
amorphous phase of Bi formed at the initial stage of film growth was
qualitatively explained by the formation of metallic droplets within the
electron glass.Comment: 7 pages, 6 figure
Measurements of the observed cross sections for exclusive light hadrons containing at , 3.650 and 3.6648 GeV
By analyzing the data sets of 17.3, 6.5 and 1.0 pb taken,
respectively, at , 3.650 and 3.6648 GeV with the BES-II
detector at the BEPC collider, we measure the observed cross sections for
, , ,
and at the three energy
points. Based on these cross sections we set the upper limits on the observed
cross sections and the branching fractions for decay into these
final states at 90% C.L..Comment: 7 pages, 2 figure
Partial wave analysis of J/\psi \to \gamma \phi \phi
Using events collected in the BESII detector, the
radiative decay is
studied. The invariant mass distribution exhibits a near-threshold
enhancement that peaks around 2.24 GeV/.
A partial wave analysis shows that the structure is dominated by a
state () with a mass of
GeV/ and a width of GeV/. The
product branching fraction is: .Comment: 11 pages, 4 figures. corrected proof for journa
- …