Ionic liquid electrolyte for lithium metal batteries : physical, electrochemical, and interfacial studies of N-Methyl-N-butylmorpholinium Bis(fluorosulfonyl)imide

The ionic liquid (IL) N-methyl-N-butylmorpholinium bis(fluorosulfonyl)imide (C₄mmor FSI) is examined from physical and electrochemical perspectives. Pulsed field gradient NMR spectroscopy shows that ion diffusivities are low compared with similar, non-ethereal ILs. Ionicity values indicate that above room temperature, less than 50% of ions contribute to conductivity.

Lithium cycling in symmetrical cells using a C₄mmor FSI-based electrolyte is best demonstrated at elevated temperatures. Specific capacities of 130 mAh g⁻¹ are achieved in a Li−LiFePO₄ battery at 85 °C. FT-IR spectroscopic investigations of lithium electrodes suggest the presence of alkoxide species in the solid electrolyte interphase (SEI), implying a ring-opening reaction of C₄mmor with lithium metal. In contrast, the SEI derived from N-methyl-N-propylpiperidinium FSI lacks the alkoxide signature but shows signs of alkyl unsaturation, and the activation energy for Li+ transport through this SEI is slightly lower than that for the C₄mmor-derived SEI. Our detailed findings give insight into the capabilities and limitations of rechargeable lithium metal batteries utilizing a C₄mmor FSI electrolyte.

Gene profiling reveals hydrogen sulphide recruits death signaling via the N-methyl-D-aspartate receptor identifying commonalities with excitotoxicity

Recently the role of hydrogen sulphide (H₂S) as a gasotransmitter stimulated wide interest owing to its involvement in Alzheimer's disease and ischemic stroke. Previously we demonstrated the importance of functional ionotropic glutamate receptors (GluRs) by neurons is critical for H₂S-mediated dose- and time-dependent injury. Moreover N-methyl-D-aspartate receptor (NMDAR) antagonists abolished the consequences of H₂S-induced neuronal death. This study focuses on deciphering the downstream effects activation of NMDAR on H₂S-mediated neuronal injury by analyzing the time-course of global gene profiling (5, 15, and 24 h) to provide a comprehensive description of the recruitment of NMDAR-mediated signaling. Microarray analyses were performed on RNA from cultured mouse primary cortical neurons treated with 200 µM sodium hydrosulphide (NaHS) or NMDA over a time-course of 5–24 h. Data were validated via real-time PCR, western blotting, and global proteomic analysis. A substantial overlap of 1649 genes, accounting for over 80% of NMDA global gene profile present in that of H₂S and over 50% vice versa, was observed. Within these commonly occurring genes, the percentage of transcriptional consistency at each time-point ranged from 81 to 97%. Gene families involved included those related to cell death, endoplasmic reticulum stress, calcium homeostasis, cell cycle, heat shock proteins, and chaperones. Examination of genes exclusive to H₂S-mediated injury (43%) revealed extensive dysfunction of the ubiquitin-proteasome system. These data form a foundation for the development of screening platforms and define targets for intervention in H₂S neuropathologies where NMDAR-activated signaling cascades played a substantial role. J. Cell. Physiol. 226: 1308–1322, 2011.

Methyl 3-[4-(4-nitrobenzyloxy)phenyl]propanoate

The title compound, C17H17NO5, crystallizes with two molecules (A and B) in the asymmetric unit. The conformational structures of the two molecules show small but significant differences in the dihedral angles between the two aryl rings with values of 18.8 (1)_ for molecule A and 7.5 (1)_ for molecule B. In molecule A, the propanoate group is twisted out of the plane of the benzene group [Car—Car—C—C torsion angle = _44.9 (2)_], while for molecule B, this group lies closer to the plane [Car—Car—C—C torsion angle = 8.6 (3)_]. C—H_ _ _O interactions characterize the crystalpacking interactions in this compound.

Functional (GT)n polymorphisms in promoter region of N-methyl-d-aspartate receptor 2A subunit (GRIN2A) gene affect hippocampal and amygdala volumes

The glutamate system including N-methyl-d-aspartate (NMDA) affects synaptic formation, plasticity and maintenance. Recent studies have shown a variable (GT)n polymorphism in the promoter region of the NMDA subunit gene (GRIN2A) and a length-dependent inhibition of transcriptional activity by the (GT)n repeat. In the present study, we examined whether the GRIN2A polymorphism is associated with regional brain volume especially in medial temporal lobe structures, in which the NMDA-dependent synaptic processes have been most extensively studied. Gray matter regions of interest (ROIs) for the bilateral amygdala and hippocampus were outlined manually on the magnetic resonance images of 144 healthy individuals. In addition, voxel-based morphometry (VBM) was conducted to explore the association of genotype with regional gray matter volume from everywhere in the brain in the same sample. The manually measured hippocampal and amygdala volumes were significantly larger in subjects with short allele carriers (n = 89) than in those with homozygous long alleles (n = 55) when individual differences in intracranial volume were accounted for. The VBM showed no significant association between the genotype and regional gray matter volume in any brain region. These findings suggest that the functional GRIN2A (GT)n polymorphism could weakly but significantly impact on human medial temporal lobe volume in a length-dependent manner, providing in vivo evidence of the role of the NMDA receptor in human brain development.

Structure and transport properties of a plastic crystal ion conductor : Diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate

Understanding the ion transport behavior of organic ionic plastic crystals (OIPCs) is crucial for their potential application as solid electrolytes in various electrochemical devices such as lithium batteries. In the present work, the ion transport mechanism is elucidated by analyzing experimental data (single-crystal XRD, multinuclear solid-state NMR, DSC, ionic conductivity, and SEM) as well as the theoretical simulations (second moment-based solid static NMR line width simulations) for the OIPC diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate ([P1,2,2,4][PF6]). This material displays rich phase behavior and advantageous ionic conductivities, with three solid–solid phase transitions and a highly “plastic” and conductive final solid phase in which the conductivity reaches 10–3 S cm–1. The crystal structure shows unique channel-like packing of the cations, which may allow the anions to diffuse more easily than the cations at lower temperatures. The strongly phase-dependent static NMR line widths of the 1H, 19F, and 31P nuclei in this material have been well simulated by different levels of molecular motions in different phases. Thus, drawing together of the analytical and computational techniques has allowed the construction of a transport mechanism for [P1,2,2,4][PF6]. It is also anticipated that utilization of these techniques will allow a more detailed understanding of the transport mechanisms of other plastic crystal electrolyte materials.

Reinforcement of natural rubber with core-shell structure silica-poly(Methyl Methacrylate) nanoparticles

A highly performing natural rubber/silica (NR/SiO2) nanocomposite with a SiO2 loading of 2 wt% was prepared by combining similar dissolve mutually theory with latex compounding techniques. Before polymerization, double bonds were introduced onto the surface of the SiO2 particles with the silane-coupling agent. The core-shell structure silica-poly(methyl methacrylate), SiO2-PMMA, nanoparticles were formed by grafting polymerization of MMA on the surface of the modified SiO2 particles via in situ emulsion, and then NR/SiO2 nanocomposite was prepared by blending SiO2-PMMA and PMMA-modified NR (NR-PMMA). The Fourier transform infrared spectroscopy results show that PMMA has been successfully introduced onto the surface of SiO2, which can be well dispersed in NR matrix and present good interfacial adhesion with NR phase. Compared with those of pure NR, the thermal resistance and tensile properties of NR/SiO2 nanocomposite are significantly improved.

Hope for resurrecting a functionally extinct parrot or squandered social capital? Landholder attitudes towards the Orange-bellied Parrot (Neophema chrysogaster) in Victoria, Australia

In early 2010, after 27 years of recovery effort, the orange-bellied parrot (OBP; Neophema chrysogaster) was expected to be extinct in the wild within a few years. Shortly before the imminent wild extinction became evident, we surveyed landholders (114 responses of 783 surveys delivered) in part of the main non-breeding area, according to three classes of modelled habitat suitability ('high', 'medium', and 'low'). Predictions of the habitat models appear to correlate with landholder perceptions of the presence of OBP habitat on private land, thus the models appear a tractable way to identify key stakeholders worthy of priority consultation in relation to habitat works. Landholders were sympathetic to wetlands and birds, including OBPs (89.4% were aware of OBPs). Most indicated that they would be upset if the OBP went extinct and agreed that critical habitat should be protected; 80.7% were prepared to consider changes to the way they managed their land to benefit the species, and sought more information on how they could do so (64.0%). This study suggests that the habitat model usefully identified key stakeholders and the OBP enjoyed high awareness, concern, and engagement among many stakeholders, shortly before the species was considered functionally extinct. The maintenance of landholder support is likely to be critical if future attempts are made to reintroduce the species to the wild.