No abstract

We report the synthesis of a completely new, stable class of inorganic salts named the dinitramide salts. These salts are based on a newly discovered nitrogen oxide anion known as the dinitramide anion. The dinitramide anion is a uniquely stable, high oxygen density grouping that can be prepared in many salt combinations including the ammonium or hydrazinium salts. The dinitramide anion has both fundamental scientific interest and practical applications. We describe here the synthesis of dinitramide salts and give a preliminary report on their properties.

The chemical stability of repository compounds is affected by various environmental conditions during long-term storage. Studies were carried out to evaluate the effects of the following potential causes of instability of compounds in DMSO at a 10-mM concentration: water, oxygen, freeze/thaw cycles, and storage container material. A set of compounds was selected for the study based on structural diversity and functional group representation. Compound concentration was determined with liquid chromatography/ultraviolet spectroscopy/mass spectrometry (LC/UV/MS) analysis relative to an internal standard added to each sample. An accelerated study was conducted, and results demonstrate that most compounds are stable for 15 weeks at 40 degrees C. Water is more important in causing compound loss than oxygen. The freeze/thaw cycle study was done with freezing at -15 degrees C and thawing under nitrogen atmosphere at 25 degrees C. Two methods were used to redissolve compounds after thawing: agitation and repeated aspiration/dispense. The results indicate no significant compound loss after 11 freeze/thaw cycles. Compound recovery was also measured from glass and polypropylene containers for 5 months at room temperature, and no significant difference was found for these 2 types of containers.

No abstract

No abstract

No abstract

Background The global burden of injury is receiving recognition as a major public health problem but inadequate information delays many proposed solutions. Many attempts to collect reliable data on orthopaedic trauma have been unsuccessful. The Surgical Implant Generation Network (SIGN) database is one of the largest collections of fracture cases from lower and middle income countries. Questions/purposes We describe the information in the SIGN database then address two questions: In the context of the design and implementation of a global trauma database, what lessons does the SIGN database teach? Does the SIGN program have a role in the evolution of a wider global system? Methods The SIGN database is Internet based. After treating a patient with a SIGN nail surgeons enter radiographs and details of the case.

The hydroperoxy radical, H02, plays an important role in the chemistry of the atmosphere, in combustion processes, and in a variety of biological and chemical oxidative systems. However, the electron affinity of this species has never been measureddirectly. An estimate by Weiss1 placed this quantity at 4.6 eV.Recently, Benson and Nangia2 have obtained 1.85 ± 0.12 eV on the basis of a thermochemical cycle employing solution data.