(Records from Medline are always below records from CAPLUS, also sorted in reverse chronological order.) You can re-sort a results set by author, document title, citing references, or reverse publication year. The default sort for references is by the database accession number, which is essentially the same as reverse-date: newest documents are on top, the oldest at the bottom. In these cases it's usually better to start a chemical name search under the Explore Substances tab. However, the more complex the chemical name, the less likely an exact match will be found, due to vagaries of nomenclature and punctuation.
Chemical names included in topic queries are searched in the synonym index of the Registry file, and if an exact match is found that compound's Registry number is added to your query.'determination' = 'detn' 'analysis'/'analytical' = 'anal'), and these are always automatically translated. CAS uses its own standard abbreviations for many words frequently found in abstracts and index terms (ex. Abbreviations that are ambiguous or non-standard will not be translated in this way. Example: 'NMR' = 'nuclear magnetic resonance'. SciFinder recognizes and translates some abbreviations.SciFinder uses an internal thesaurus of synonyms, so you'll occasionally see words you didn't search included in your results.It also combines common British and American spellings: 'color' = 'colour' etc. Redoing your search with a NOT qualifier sometimes gets rid of a specific unwanted term. Sometimes auto-truncation includes totally irrelevant terms in your results. SciFinder truncates most simple plurals automatically and includes both in your results. SciFinder auto-truncates (stems) your words in most cases, so it ignores common wildcard symbols like * or #.Note that none of the algorithmic processes described below will have been performed on this exact "as entered" phrase. If you want to search an exact phrase, type the phrase without quotation marks (which are ignored), and select the first option in the results list: "X references were found containing 'A B C' as entered." You will only see this option if there was an exact match of your search string in the database.Think about what keywords are likely to be used in titles and abstracts relevant to your topic, and stick with those. Avoid including generic or meaningless words that may limit your results unnecessarily. Slight differences in the way you phrase a query can retrieve different results, so consider trying your search several different ways.If your topic is inherently complex, start with a simple search of the most important concepts, then narrow down the results using the Analyze or Refine options. (The system limit is 7.) A query that is too complex will usually result in few if any hits. Try to keep your query to no more than 3 or 4 distinct concepts.
Avoid long, complex queries as with all databases, simpler is usually better.Example: 'lead content in paint (pigments, coatings)'. In place of the OR operator, you can include synonyms or alternate terms in parentheses, separated by commas, following the word in question.SciFinder does not use Boolean operators in a conventional way.You can get around this somewhat by selecting the more restrictive "as entered" option in the results table. For example, 'determination of arsenic' is processed the same way as 'determination in arsenic' even though the two phrases mean different things to a chemist. Connector words are not searchable terms, nor are they analyzed for their linguistic meaning. SciFinder uses connectors (also known as stopwords: AN, AND, AS, AT, BY, FOR, FROM, IN, OF, ON, OR, THE, TO, and WITH) to parse a query into component concepts.single walled carbon nanotubes in thin film transistors.Compose a natural-language query phrase with at least two distinct concepts, linked with connecting words.Here is a short list of important searching points unique to SciFinder. This can sometimes cause frustration when you're trying to isolate records very carefully. It is not designed to be a highly precise search tool for expert searchers. SciFinder's topic search was designed to maximize retrieval, so some of its imprecision is intentional. SciFinder uses a proprietary, complex (and somewhat mysterious) natural language query algorithm that breaks your query into a set of discrete concepts, searches them against the database indexes, and then presents you with a selection of result options. The Explore by Research Topic option presents a single text box that looks like Google's, but SciFinder's search algorithm functions very differently from those of standard web search-engines.
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