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 ...