Automatic processing of the bibliography on vapor-liquid equilibrium data is done by means of a specially developed mnemonic coding system. (Author/JB)

The boundary between two neighboring rings is called the fusion lines, which is enclosed by external segments called arcs. In the code, the separation of fusion line(s) from arcs takes place in such a way that proper matching is achieved. By this procedure, the structure of a compound is recreated. (Author)

Analysis of the distribution of relevant answers to 41 search profiles among the 80 subject sections of Chemical Abstracts" revealed that the average profile requires 10 CA-subject sections for adequate coverage. The average printing expense could be reduced 25 percent by searching the individual profiles in the appropriate subject sections. (5…

Two systems, WLN and Ringcode, for retrieving structural information were analyzed qualitatively and evaluated for a series of chemical compounds. The studies ranged from specific to generic questions and also involved retrieval by fragments. Neither system was completely satisfactory for all types of searches. (6 references) (Author)

Techniques, media, and systems for making organized data available exist, but have not been used extensively enough. Reasons for failure to use these are explored and recommendations made for extraction by authors at time of writing, centralized organization, and publication through existing organization. Datum signatures are described. (50…

The techniques of search strategy design for substructure searches of the Wiswesser Line Notation (WLN) file are described in detail. The Index Chemicus Registry System'' was used. (13 references) (Author/SM)

The set reduction algorithm is based on set theory and Boolean algebra rather than the graph-theoretic approach. Time trials with a small file of organic chemical structures indicate that the algorithm can be economically used for substructure (or complete structure) sequential searches on a file containing 30,000-50,000 computer-coded structures.…

The TSS (Topological Screens System) for substructure search was applied to the CAS Registry file making it searchable on-line. The TSS screens and the use of the screen indexes are described. Statistics on screen assignment are provided, and the strengths and weaknesses of the system are discussed. (Author/NH)

The relative retrieval performances of the CA Integrated Subject File (CAISF), CA Condensates, and a Merged File created from these two data bases were measured. Retrieval performance is reported in terms of recall, precision values, and costs. (Author/JB)

Minimum, maximum, and average lengths and frequency counts for the data elements in the Chemical Substance and General Subject segments of the Standard Distribution Format (SDF) files distributed by Chemical Abstracts Service are presented. (5 references) (Authors)

The state of the art for document access is briefly reviewed and a reasonably far look into the future is presented in this paper. (40 references) (Author/NH)