A nuclear magnetic resonance study of 15 phosphine-boranes has been undertaken with the view to investigating the electronic nature of the P-B dative bond. A correlation between the ³¹P-¹¹B coupling constant and the base ...

Temporal references in natural language include tenses and other time relations, references to specific times, and a variety of phrases such as "present", "later", "when", "how often", and "never". Their high frequency of ...

Bat Cave quadrangle lies on the maturely dissected eastern margin of the Edwards Plateau. Sinkholes, caves, and other karst features are common throughout the uplands. Approximately 1,050 feet of dominantly carbonate rock ...