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NO is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four nitroxyl molecules. N is bonded in a single-bond geometry to one O atom. The N–O bond length is 1.17 Å. O is bonded in a single-bond geometry to one N atom.
HI1 is alpha carbon monoxide-like structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of sixteen hydriodic acid molecules. H1+ is bonded in a single-bond geometry to one I1- atom. The H–I bond length is 1.64 Å. I1- is bonded in a single-bond geometry to one H1+ atom.
TcB is alpha carbon monoxide-like structured and crystallizes in the hexagonal P6_3mc space group. The structure is zero-dimensional and consists of two TcB clusters. Tc3- is bonded in a single-bond geometry to one B3+ atom. The Tc–B bond length is 1.77 Å. B3+ is bonded in a single-bond geometry to one Tc3- atom.
AgI is alpha carbon monoxide-like structured and crystallizes in the hexagonal P6mm space group. The structure is zero-dimensional and consists of one silver iodide molecule. Ag1+ is bonded in a single-bond geometry to one I1- atom. The Ag–I bond length is 2.56 Å. I1- is bonded in a single-bond geometry to one Ag1+ atom.
ClF is alpha carbon monoxide-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four chlorine fluoride molecules. Cl is bonded in a single-bond geometry to one F atom. The Cl–F bond length is 1.69 Å. F is bonded in a single-bond geometry to one Cl atom.
HBr is alpha carbon monoxide structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules. H1+ is bonded in a single-bond geometry to one Br1- atom. The H–Br bond length is 1.44 Å. Br1- is bonded in a single-bond geometry to one H1+ atom.
CO is alpha carbon monoxide-like structured and crystallizes in the trigonal R3c space group. The structure is zero-dimensional and consists of twenty-four formaldehyde molecules. C2+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.14 Å. O2- is bonded in a single-bond geometry to one C2+ atom.
HBr is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrobromic acid molecules. H1+ is bonded in a single-bond geometry to one Br1- atom. The H–Br bond length is 1.47 Å. Br1- is bonded in a single-bond geometry to one H1+ atom.
HF is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrofluoric acid molecules. H1+ is bonded in a single-bond geometry to one F1- atom. The H–F bond length is 0.95 Å. F1- is bonded in a single-bond geometry to one H1+ atom.
HCl is alpha carbon monoxide-like structured and crystallizes in the orthorhombic Cmc2_1 space group. The structure is zero-dimensional and consists of four hydrochloric acid molecules. H1+ is bonded in a single-bond geometry to one Cl1- atom. The H–Cl bond length is 1.30 Å. Cl1- is bonded in a single-bond geometry to one H1+ atom.
BrCl is alpha carbon monoxide-like structured and crystallizes in the hexagonal P6_3mc space group. The structure is zero-dimensional and consists of two bromine chloride molecules. Br is bonded in a single-bond geometry to one Cl atom. The Br–Cl bond length is 2.17 Å. Cl is bonded in a single-bond geometry to one Br atom.
CO is alpha carbon monoxide-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four formaldehyde molecules. C2+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.14 Å. O2- is bonded in a single-bond geometry to one C2+ atom.
NO is alpha carbon monoxide-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four nitroxyl molecules. N is bonded in a single-bond geometry to one O atom. The N–O bond length is 1.17 Å. O is bonded in a single-bond geometry to one N atom.
NO is alpha carbon monoxide-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four nitroxyl molecules. N is bonded in a single-bond geometry to one O atom. The N–O bond length is 1.17 Å. O is bonded in a single-bond geometry to one N atom.
The loss of the Space Shuttle Columbia as a result of impact damage from foam debris during ascent has led NASA to investigate the feasibility of on-board impact detection technologies. AE sensing has been utilized to monitor a wide variety of impact conditions on Space Shuttle components ranging from insulating foam and ablator materials, and ice at ascent velocities to simulated hypervelocity micrometeoroid and orbital debris impacts. Impact testing has been performed on both reinforced carbon composite leading edge materials as well as Shuttle tile materials on representative aluminum wing structures. Results of these impact tests will be presented with a focus on the acoustic emission sensor responses to these impact conditions. These tests have demonstrated the potential of employing an on-board Shuttle impact detection system. We will describe the present plans for implementation of an initial, very low frequency acoustic impact sensing system using pre-existing flight qualified hardware. The details of an accompanying flight measurement system to assess the Shuttle s acoustic background noise environment as a function of frequency will be described. The background noise assessment is being performed to optimize the frequency range of sensing for a planned future upgrade to the initial impact sensing system.
Thermal analyses were conducted to evaluate the thermal response of various individual materials and multi-layer configurations for an in-space heat shield exposed to a rocket plume during stage separation. Frequently used, readily available thermal protection materials consisting of cork, carbon cloth phenolic (CCP), and silica cloth phenolic (SCP) were selected for an initial screening analysis. SCP was chosen as the primary material for further evaluation using an updated thermal environment calculated using computational fluid dynamics (CFD) results. A multi-layer configuration consisting of SCP providing erosion resistance and a Nomex honeycomb providing thermal protection was then evaluated as a solution for more mass-efficient performance. Pyrolysis depth, bondline temperature, back-side temperature, and a thermal factor of safety were used to define the necessary material thickness profile. Adhesives were included in the analyses with considerations for maximum temperature and application method. One dimensional thermal analyses at several stations along the heat shield surface were performed for the initial screening and follow-on analyses. The methodology used standard processes and computer programs applicable to solid rocket motor internal insulation and nozzle thermal analysis such as Chemical Equilibrium and Applications (CEA), Aerotherm Chemical Equilibrium (ACE), Momentum/Energy Integral Technique (MEIT), and Insulation Thermal Response and Ablation Code (ITRAC). The baseline SCP/Nomex honeycomb multi-layer configuration thermal performance predictions satisfied the objectives with an acceptable mass estimate for the design maturity. The EA9673 film adhesive and SCP resin were the best performing bonding agents considered for the SCP/Nomex honeycomb and Nomex honeycomb/structural substrate interfaces. The baseline mass estimate was lowest when the resin was the bonding agent due to the higher maximum service temperature. These thermal analyses evaluated typical internal and external nozzle materials using a calculated thermal environment and heat loads that were lower than a typical rocket motor internal environment but greater than standard external aeroheating.
Traditional solution-state NMR experiments may either fail or yield unsatisfactory results when employing fully- 13 C-labeled biomass due to complications arising from 13 C– 13 C coupling. Constant-time analogs of HSQC experiments mitigate such issues and deliver enhanced sensitivity. A rarely reported CT-HSQC-TOCSY experiment allows the proton coupling network to deliver much of the same value as the parent experiment on unlabeled or 10–15%- 13 C-labeled biomass polymers but with enhanced sensitivity. In the absence of a viable HMBC analog for long-range correlations, a relayed C–C experiment, i.e., via directly bonded 13 C-labeled networks, enables the reliable assignment of coupled carbons, with the added advantage of correlating the more elusive quaternaries. A C–C-FLOPSY experiment takes advantage of fully- 13 C-labeled materials for mapping extensive carbon networks in the complex polymer mixtures inherent in biomass. Various pendent groups (tricin units, cis- and trans-p-coumarates, and p -hydroxybenzoates) that adorn lignins, and the cis- and trans-ferulates on arabinoxylan polysaccharides, are exquisitely revealed in spectra from isolated lignins or whole-cell-wall materials from maize, sorghum, and poplar.
Novel crystalline porous materials known as metal-organic frameworks (MOFs) and methods for their synthesis are provided herein. The MOFs include a M6(μ3-OH)8(OH)8(μ2,η2-(O2C)2cyclam)8 cluster, and a metal atom coordinated to the one or more cyclam of the cluster, wherein M is Zr or Hf, and the metal atom is any one of Cu, Ni, Cr, Ru, Co, and Gd. The MOFs can be used as an adsorbent, alone or in a medium with other components, of CO2. The MOFs can also be used as a catalyst for the transformation of CO2 and epoxides to cyclic carbonates. The MOFs can also be used in the electrochemical catalytic reduction of CO2. The MOFs can also be used for photocatalytic CO2 reduction for the production of carbon-based fossil fuels. The MOFs can also be used for light-induced nitric oxide (NO) release. The MOFs can also be used as magnetic resonance imaging (MRI) agents.