RESUMEN
Since the late 1960s, the exact structure of cubic calcium silicon nitride has been a source of debate. This paper offers evidence that the cubic phase CaSiN(2) described in the literature is actually Ca(16)Si(17)N(34). Presented here is a method for synthesizing single crystals of cubic-calcium silicon nitride from calcium nitride and elemental silicon under flowing nitrogen at 1500 °C. The colorless millimeter-sized crystals of Ca(16)Si(17)N(34) with a refractive index (n(25)) = 1.590 were found to be cubic (a = 14.8882 Å) and belong to the space group F43m (216). The synthesis of bulk, powdered cubic-Ca(16)Si(17)N(34) from calcium cyanamide and silicon is also discussed. Ca(16)Si(17)N(34) is a relatively air-stable refractory ceramic. In contrast to the orthorhombic phase of CaSiN(2), in which Ca(2+) sits in octahedral sites, this cubic phase has Ca(2+) in cubic sites that makes it an interesting host for new phosphors and gives rise to unique crystal field splitting.
RESUMEN
Psilocin was identified in a urine specimen collected during a routine driving under the influence of drugs investigation, the first for this laboratory. The subject did not exhibit any response to an automobile crash, indicating the he may have been unaware of the severity of the situation or his immediate surroundings. The urine specimen gave a positive result on a fluorescence polarization immunoassay amphetamine/methamphetamine assay, and psilocin was determined to have 1.3% cross-reactivity at 50 mg/L. Psilocin was confirmed by gas chromatography-mass spectrometry following an extraction for acidic, neutral, and basic drugs. Hydrolysis and derivatization techniques were not employed. The urine concentration of psilocin decreased rapidly, although the specimen was maintained at 4 degrees C.
