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Silvestri N.M.,University of Washington | Szkody P.,University of Washington | Mukadam A.S.,University of Washington | Hermes J.J.,University of Texas at Austin | And 3 more authors.
Astronomical Journal | Year: 2012

We report Galaxy Evolution Explorer NUV and optical follow-up observations of the cataclysmic variable V455 And at 3years past its large amplitude dwarf nova outburst. Orbital and superhump variations are evident in the NUV and optical light curves. We clearly detect the spin along with a photometric variation that we tentatively attribute to non-radial pulsations in the Discrete Fourier Transforms at both wavelengths. The increased amplitude of the spin and pulsation in the NUV versus the optical implies an origin near the white dwarf. The shorter pulsation period after outburst is indicative of a white dwarf that remains hotter than at quiescence. © © 2012. The American Astronomical Society. All rights reserved. Source

Murray N.H.,Michigan State University | Low E.M.,Heritage High School | Pochodylo A.L.,Michigan State University | LaDuca R.L.,Michigan State University
Inorganica Chimica Acta | Year: 2015

Hydrothermal reaction of copper nitrate and aromatic dicarboxylate precursors with the conformationally flexible and very long-spanning dipyridylamide ligand propane-1,3-diylbis(piperidine-4,1-diyl)bis(pyridin-4-ylmethanone) (4-ppbp) has generated three coordination polymers and a threaded-loop supramolecular complex. {[Cu(tere)(4-ppbp)(H2O)]·1.5H2O}n (1, tere = terephthalate) and {[Cu(iph)(4-ppbp)(H2O)]·2H2O}n (2, iph = isophthalate) both display slab motifs built from interdigitated (4,4) grid layers. {[Cu2(phda)(phdaH)2(4-ppbp)2]·6H2O}n (3, phda = 1,4-phenylenediacetate) possesses a 4-connected 658 cds network with self-penetration of 8-membered circuits. {[Cu2(phtH)2(4-ppbp)2(H2O)4](NO3)2·H2O}n (4, pht = phthalate) manifests ring-like dinuclear coordination complex cations with anionic phtH ligands projecting into supramolecular tubes with an inner diameter of approximately 12 Å. Dehydration and thermal degradation properties of these new materials are discussed. We also report the crystal structure of the recrystallized dipyridylamide, 4-ppbp·2H2O. © 2015 Elsevier B.V. All rights reserved. Source

Hydrothermal reaction of zinc nitrate, aliphatic dicarboxylic acids, and the long-spanning hydrogen-bonding capable tethering ligand bis(4-pyridylmethyl)piperazine (4-bpmp) has produced seven coordination polymer solids that were characterized via single-crystal X-ray crystallography. [Zn(suc)(4-bpmp)(H2O)2]n (1, suc = succinate) shows 2D + 2D → 3D mutually inclined interpenetrated parallel coordination polymer layers with (4,4) grid topology. {[Zn2(dms)2(4-bpmp)]·2H2O}n (2, dms = 2,2-dimethylsuccinate) exhibits 1-D [Zn2(dms)2]n ribbons featuring {Zn2(OCO)2} dimeric units pillared into 2-D by 4-bpmp ligands. {[Zn(glu)(4-bpmp)]·6H2O}n (3, glu = glutarate) manifests a 3-fold interpenetrated 3-D 66 diamondoid topology with embedded C(10)A(4) water chains. [Zn(22dmg)(4-bpmp)]n (4, 22dmg = 2,2-dimethylglutarate) and [Zn(33dmg)(4-bpmp)]n (5, 33dmg = 3,3-dimethylglutarate) both display stacked zig-zag (4,4) grid layered topologies, and do not entrain any co-crystallized water molecules. Reduction of the steric hindrance by using 3-methylglutarate (3mg) afforded {[Zn(3mg)(4-bpmp)]·3H2O}n (6), which also displays a (4,4) grid topology, but with embedded R(4)A(2) water molecule hexamers connecting to three different layer motifs. [Zn(adp)(4-bpmp)]n (7, adp = adipate) possesses a system of 5-fold interpenetrated diamondoid nets. Thermal and luminescent properties of these materials are discussed herein. © 2014 Elsevier B.V. All rights reserved. Source

Hill H.,Heritage High School
Teaching Geography | Year: 2012

The article describes a live e-mission activity when year 10 students formed an Emergency Response Team to ensure the safety of the residents of Montserrat as they face a volcanic eruption and a hurricane. The e-mission activity from the National Space Center in Leicester involves students working together as an emergency response team to ensure the safety of the islanders of Montserrat. The activity supported a year 10 unit of work looking at the impacts of volcanic eruptions and how they are monitored. The evacuation team had a large map of the island showing the towns and roads. They had to use information from the mission commander at the Space Center, via the webcam, and input from the other teams to decide which parts of the island were in danger and where the residents should be evacuated to. Source

Low E.M.,Heritage High School | Laduca R.L.,Michigan State University
Acta Crystallographica Section E: Structure Reports Online | Year: 2014

In the title co-crystal, C25H32N4O2C14H10O5, molecules are connected into supramolecular chains aligned along [102] by O-H⋯N hydrogen bonding. These aggregate into supramolecular layers oriented parallel to (20-1) by C-H⋯O interactions. These layers then stack in an ABAB pattern along the c crystal direction to give the full three-dimensional crystal structure. The central chain in the dipyridylamide has an anti-anti conformation. The dihedral angle between the aromatic ring planes is 29.96(3)°. Disorder is noted in some of the residues in the structure and this is manifested in two coplanar dispositions of one statistically disordered carboxylic acid group. Source

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