Oxygen impact and reactivity trials: A new perspective on emergency response precautions.

The objective of this research was to verify and qualify what has been traditionally taught as fact during first responder's hazardous materials training regarding response precautions to and the likely behaviors of liquid oxygen (LOx) during a release. Subject matter experts disagreed that these precautions were well-founded in precedent or science. Findings showed that impact pressure causes a reaction in LOx and asphalt under specific conditions.

Solid-State C NMR Evidence for Long Multicenter Intradimer Bonding in Zwitterion-like Structures.

The principal values of the C chemical shift tensor for the β and δ polymorphs of π-[TTF⋅⋅⋅TCNE] (TTF=tetrathiafulvalene; TCNE=tetracyanoethylene) have been analyzed to understand the abnormally long intra-dimer bonding of singlet π-[TTF ⋅⋅⋅TCNE ]. These structures possess 12 intradimer contacts <3.40 Å, with the shortest intra π-[TTF⋅⋅⋅TCNE] separations involving 2-center (2c) C-S and 3c C-C-C orbital overlap contributions between the [TTF] and [TCNE] .

Solid-state 13C NMR investigations of cyclophanes: [2.2]paracyclophane and 1,8-dioxa[8](2,7)pyrenophane.

Solid-state NMR (ssNMR) and ab initio quantum mechanical calculations are used in order to understand and to better characterize the molecular conformation and properties of [2.2]paracyclophane and 1,8-dioxa[8](2,7)pyrenophane. Both molecules are cyclophanes, consisting of an aromatic ring assembly and a cyclic aliphatic chain connected to both ends of the aromatic portion.

Solid-State NMR spectra and long, intra-dimer bonding in the pi-[TTF](2)(2+) (TTF = tetrathiafulvalene) dication.

The (13)C chemical-shift tensor principal values for TTF and pi-[TTF](2)(2+) (TTF = tetrathiafulvalene) dimer dications have been measured in order to better understand the electronic structure and long intradimer bonding of these TTF-based dimer structures. The structure of pi-[TTF](2)(2+) is abnormal due to its two C-C and four S-S ca. 3.

Solid-state 13C NMR investigations of 4,7-dihydro-1H-tricyclopenta[def,jkl,pqr]triphenylene (sumanene) and indeno[1,2,3-cd]fluoranthene: Buckminsterfullerene moieties.

4,7-Dihydro-1H-tricyclopenta[def,jkl,pqr]triphenylene (sumanene) and indeno[1,2,3-cd]fluoranthene (indenofluoranthene) are structural moieties related to Buckminsterfullerene (C(60)). As such, understanding their structural characteristics is of great interest because of the insight they shed upon C(60). Hence, solid-state NMR (ssNMR) and ab initio quantum mechanical calculations with Gaussian03 are used in order to understand and to better characterize the molecular conformation and properties of sumanene and indenofluoranthene.

Metal complexation of chitosan and its glutaraldehyde cross-linked derivative.

The physicochemical characterization of metal complexed with chitosan (CS) and its glutaraldehyde cross-linked derivative (CSGA) was investigated. Seven metal ions from chromium through zinc of the first row of the transition metals were selected for complexation. Structural features pertinent to where and how metals bind into both polymers are our main interest.

Ring current effects in crystals. Evidence from 13C chemical shift tensors for intermolecular shielding in 4,7-di-t-butylacenaphthene versus 4,7-di-t-butylacenaphthylene.

13C chemical shift tensor data from 2D FIREMAT spectra are reported for 4,7-di-t-butylacenaphthene and 4,7-di-t-butylacenaphthylene. In addition, calculations of the chemical shielding tensors were completed at the B3LYP/6-311G** level of theory. While the experimental tensor data on 4,7-di-t-butylacenaphthylene are in agreement with theory and with previous data on polycyclic aromatic hydrocarbons, the experimental and theoretical data on 4,7-di-t-butylacenaphthene lack agreement.