A Perspective on the Synthesis, Purification, and Characterization of Porous Organic Cages

[Image: see text] Porous organic cages present many opportunities in functional materials chemistry, but the synthetic challenges for these molecular solids are somewhat different from those faced in the areas of metal–organic frameworks, covalent–organic frameworks, or porous polymer networks. Here, we highlight the practical methods that we have developed for the design, synthesis, and characterization of imine porous organic cages using CC1 and CC3 as examples. The key points are transferable to other cages, and this perspective should serve as a practical guide to researchers who are new to this field

Technology Transfer and Innovation Policy at Canadian Universities: Opportunities and Social Costs

This project examines the role of universities in transmitting knowledge in the forms of technology transfer mechanisms, intellectual property (IP) agreements and other knowledge diffusion policies

The HI gas content of galaxies around Abell 370, a galaxy cluster at z = 0.37

We used observations from the Giant Metrewave Radio Telescope to measure the atomic hydrogen gas content of 324 galaxies around the galaxy cluster Abell 370 at a redshift of z = 0.37 (a look-back time of ~4 billion years). The HI 21-cm emission from these galaxies was measured by coadding their signals using precise optical redshifts obtained with the Anglo-Australian Telescope. The average HI mass measured for all 324 galaxies is (6.6 +- 3.5)x10^9 solar masses, while the average HI mass measured for the 105 optically blue galaxies is (19.0 +- 6.5)x10^9 solar masses. The significant quantities of gas found around Abell 370, suggest that there has been substantial evolution in the gas content of galaxy clusters since redshift z = 0.37. The total amount of HI gas found around Abell 370 is up to ~8 times more than that seen around the Coma cluster, a nearby galaxy cluster of similar size. Despite this higher gas content, Abell 370 shows the same trend as nearby clusters, that galaxies close to the cluster core have lower HI gas content than galaxies further away. The Abell 370 galaxies have HI mass to optical light ratios similar to local galaxy samples and have the same correlation between their star formation rate and HI mass as found in nearby galaxies. The average star formation rate derived from [OII] emission and from de-redshifted 1.4 GHz radio continuum for the Abell 370 galaxies also follows the correlation found in the local universe. The large amounts of HI gas found around the cluster can easily be consumed by the observed star formation rate in the galaxies over the ~4 billion years (from z = 0.37) to the present day.Comment: accepted by MNRA

Controlling electric double-layer capacitance and pseudocapacitance in heteroatom-doped carbons derived from hypercrosslinked microporous polymers

© 2018 Hypercrosslinked polymers (HCPs) are an important class of porous materials that can be synthesized from aromatic precursors using a one-step “knitting” procedure. This scalable process allows wide synthetic diversity and ease of functionalization. However, pristine HCPs lack electrical conductivity, which limits their potential for electrochemical applications. Supercapacitors are energy storage devices with advantages over conventional batteries such as high power densities, rapid charge speeds, and superior cyclability. In this work, carbonization of functionalized HCPs yields highly conductive and porous materials that can be used as supercapacitor electrodes. Both electric double-layer capacitance (EDLC) and pseudocapacitance (PC) mechanisms are observed. The relative EDLC and PC contributions were quantified for a range of 20 HCP-derived materials, thus allowing a controlled approach to tuning the energy storage properties. The HCP-based carbons show ideal supercapacitor behavior and the best performing material, which shows 63% PC, displays exceptionally high capacitances of up to 374 F g −1 , excellent capacitance retention at fast charging speeds, and stability for up to 15,000 charge/discharge cycles

PDV Probe Efficiency Study using the Luna

Author Institution: Los Alamos National LaboratorySlides presented at the 3nd Annual Photonic Doppler Velocimetry (PDV) Conference and Workshop held at Sandia National Laboratories, Albuquerque, New Mexico, September 3-4, 2008

Sponge-Like Behaviour in Isoreticular Cu(Gly-His-X) Peptide-Based Porous Materials

We report two isoreticular 3D peptide-based porous frameworks formed by coordination of the tripeptides Gly-l-His-Gly and Gly-l-His-l-Lys to Cu(II) which display sponge-like behaviour. These porous materials undergo structural collapse upon evacuation that can be reversed by exposure to water vapour, which permits recovery of the original open channel structure. This is further confirmed by sorption studies that reveal that both solids exhibit selective sorption of H(2)O while CO(2) adsorption does not result in recovery of the original structures. We also show how the pendant aliphatic amine chains, present in the framework from the introduction of the lysine amino acid in the peptidic backbone, can be post-synthetically modified to produce urea-functionalised networks by following methodologies typically used for metal–organic frameworks built from more rigid “classical” linkers

Rural and suburban population surge following detonation of an improvised nuclear device: A new model to estimate impact

Background: The objective of the study was to model urban evacuation into surrounding communities after the detonation of an improvised nuclear device (IND) to assist rural and suburban planners in understanding and effectively planning to address the effects of population surges. Methods: Researchers developed parameters for how far evacuees would travel to escape disasters and factors that would influence choice of destination from studies of historical evacuations, surveys of citizens' evacuation intentions in hypothetical disasters, and semistructured interviews with key informants and emergency preparedness experts. Those parameters became the inputs to a "push-pull" model of how many people would flee in the 4 scenarios and where they would go. Results: The expanded model predicted significant population movements from the New York City borough of Manhattan and counties within 20 km of Manhattan to counties within a 150-mi radius of the assumed IND detonation. It also predicted that even in some communities located far from Manhattan, arriving evacuees would increase the population needing services by 50% to 150%. Conclusions: The results suggest that suburban and rural communities could be overwhelmed by evacuees from their center city following an IND detonation. They also highlight the urgency of educating and communicating with the public about radiation hazards to mitigate panic and hysteria, anticipating the ways in which a mass exodus may disrupt or even cripple rescue and response efforts, and devising creative ways to exercise and drill for an event about which there is great denial and fatalism

Technology Transfer and Innovation Policy at Canadian Universities: Opportunities and Social Costs

This report, supported by a Social Sciences and Humanities Research Council (SSHRC) Knowledge Synthesis Grant, critically examines the role of universities in transmitting knowledge in the forms of technology transfer mechanisms, intellectual property agreements and other knowledge diffusion policies. In reviewing and synthesizing the recent literature on the topic, we seek to provide some initial evidence-based policy recommendations in order to generally strengthen Canada‘s innovation ecosystem and more specifically to maximize the return on the nation‘s investment in higher education research and development

The Neandertal genome and ancient DNA authenticity

Recent advances in high-thoughput DNA sequencing have made genome-scale analyses of genomes of extinct organisms possible. With these new opportunities come new difficulties in assessing the authenticity of the DNA sequences retrieved. We discuss how these difficulties can be addressed, particularly with regard to analyses of the Neandertal genome. We argue that only direct assays of DNA sequence positions in which Neandertals differ from all contemporary humans can serve as a reliable means to estimate human contamination. Indirect measures, such as the extent of DNA fragmentation, nucleotide misincorporations, or comparison of derived allele frequencies in different fragment size classes, are unreliable. Fortunately, interim approaches based on mtDNA differences between Neandertals and current humans, detection of male contamination through Y chromosomal sequences, and repeated sequencing from the same fossil to detect autosomal contamination allow initial large-scale sequencing of Neandertal genomes. This will result in the discovery of fixed differences in the nuclear genome between Neandertals and current humans that can serve as future direct assays for contamination. For analyses of other fossil hominins, which may become possible in the future, we suggest a similar ‘boot-strap' approach in which interim approaches are applied until sufficient data for more definitive direct assays are acquired

BurstCube: A CubeSat for Gravitational Wave Counterparts

BurstCube will detect long GRBs, attributed to the collapse of massive stars, short GRBs (sGRBs), resulting from binary neutron star mergers, as well as other gamma-ray transients in the energy range 10-1000 keV. sGRBs are of particular interest because they are predicted to be the counterparts of gravitational wave (GW) sources soon to be detectable by LIGO/Virgo. BurstCube contains 4 CsI scintillators coupled with arrays of compact low-power Silicon photomultipliers (SiPMs) on a 6U Dellingr bus, a flagship modular platform that is easily modifiable for a variety of 6U CubeSat architectures. BurstCube will complement existing facilities such as Swift and Fermi in the short term, and provide a means for GRB detection, localization, and characterization in the interim time before the next generation future gamma-ray mission flies, as well as space-qualify SiPMs and test technologies for future use on larger gamma-ray missions. The ultimate configuration of BurstCube is to have a set of $\sim10$ BurstCubes to provide all-sky coverage to GRBs for substantially lower cost than a full-scale mission.Comment: In the 35th International Cosmic Ray Conference, Busan, Kore