L I T E R A T U RE
PACIR Hunts Organic Pesticides Easier analysis plus semiautomatic coding eases process of readying information for retrieval
141ST
ACS
NATIONAL
MEETING
Chemical Literature
A patent-searching procedure known as PACIR (practical approach to chemical information retrieval) is now being readied for organic pesticide patents. The system incorporates several facets of previous search machines built by the Patent Office, operates under a combination of empirical rules dictated by experience, and employs a semiautomatic encoding procedure that both eases the lot of the patent analyst and allows some interchange of analysis efforts. PACIR evolved through experience with four different systems which altogether cover some 20,000 mechanized patent searches. Prime among the characteristics the Patent Office wanted, according to patent research specialist Julius Frome, was to make it as easy as possible to extract information from the document and put it into machine-recognizable code. This is where an information system either proves economical or fails. The analysis process itself is extremely difficult since patents range over many decades of chemistry. It has to be carefully organized and strictly controlled to provide a reliable file. At the same time, as much of the burden as possible of transferring the analysis to complex computer codes must be removed from the analyst. Accuracy is essential, but it is also essential that as many of the limitations on the analysis as possible be removed, that the system not be limited to any one area of chemistry, that it be flexible enough to handle unexpected problems and take on useful revisions, and that any such system be versatile enough to be used by more than one group. In almost any place that information has to be recovered, some of it should be recovered in detail. Other 80
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information, not quite so important, but still necessary, can be kept in general terms. This is true for organic chemistry and particularly true of chemical patents in the field. This welter of desirable characteristics is what the Patent Office has attempted to combine in PACIR. This is handled by a semiautomatic coding procedure and two types of analysis which permit a selection of the depth or detail of coding. One of the analysis procedures is an underlining and role-assigning technique for the subordinate subject matter. As an example, Mr. Frome cites organic pesticide patents. A pesticide generally has an active ingredient blended with solvents, wetting agents, emulsifiers, and other agents which are not active killers. The nonactive ingredients and their characteristics are subordinate and analyzed according to four roles: solvent, adjuvant, form, and use. Solvent, coded as S, is the medium or vehicle for the active ingredient. Adjuvants (A) are components added in minor amounts which are neither active nor carriers. Form ( F ) is physical condition: paste, spray, dust, etc. Use (U) includes the effect, where it's applied, and the type of pest affected. These terms in the patent are singled out, assigned proper roles, and key-punched onto standard cards. The cards are then used in making standard catalogs or dictionaries of the terms for machine coding. Terms are arbitrary, selected only because their content is not valuable enough to warrant the more expensive detailed procedure. This approach is not limited to patents, can be used with any subject matter less valuable than the main point of the document. A detailed analysis procedure is used for the main subject matter. With PACIR this is a minute dissection and recording of chemical structure. The procedure has been formulated for organic nomenclature in general so it
has not been limited by any particular structure. Previous systems have been limited by being coded around a unique molecule, such as the phosphorus atom on the steroid nucleus. Furthermore, the coding can be of a specific compound or of a generic one if the primary compound and a number of derivations are named. The process has three steps. First a structure is drawn; it is then converted into a linear formula and translated into a numerical code by a machineassisted procedure. Some 20 different classifications plus subdivisions designate the different fragments of a chemical formula in PACIR's linear code. These can be converted to serial or random access machine code by any convenient procedure. The format of the machine code procedure is strictly arbitrary and can be selected by the user according to his need. Initially, the computer is supplied with a dictionary of machine code. This includes both the fragment and a designation of its relationship with the rest of the particle. The computer can then be told to assemble and encode a new particle after it's entered in linear code. If the computer can't assemble the code, it says so, and the term is entered manually. This system allows changing codes by machine method. For instance, piperidine might be encoded, and another analysis prefer nitrogen heterocyclics. The original code can be run through the computer and the change made each time piperidine occurs. This way the whole code or parts of it can be changed without going back to the original document. It also allows a certain amount of leeway. Linear codes such as benzene or phenyl for a molecular unit can both be used and the machine programed to code both the same. The big advantage, however, is that this procedure makes many analyticcode procedures interchangeable. Today many are specific for a particular coding procedure. This one isn't. Once the analysis is run p r o p e r l y picking out the major and subordinate facts or ideas—it doesn't matter what kind of code the idea is transformed into; it can be changed into another by changing the dictionary that relates code to the analytic symbology. The patent office is currently developing two search files using PACIR. One is using an IBM statistical sorter, the other a RAMAC 305 computer.
in vinyl floor tile:
Vinyl floor tile and vinyl organosol topcoats show excellent resistance to stains of common household foods and soils when plasticized with Texanol A-S. And with yellow and o t h e r light d e c o r a t o r shades being recommended this year, stain resistance can become a critical factor in gaining consumer acceptance. Good maintenance properties, too, are characteristic of vinyl formulations plasticized with this new C 8 -glycol diester. Under acrylic polishes, for example, tile or coatings containing Texanol A-S show no tack or exudation on aging. Re-
sistance to oil and heptane extraction of this new Eastman plasticizer is also good. In milling operations, Texanol A-S strikes in fast at low fusing t e m p e r a t u r e s . P o w e r , h e a t and labor requirements are reduced. In vinyl organosols, Texanol A-S exhibits low initial viscosity. And good viscosity stability i n s u r e s long pot life. For full information on this useful new plasticizer, contact your Eastman representative, or write Chemicals Division, EASTMAN CHEMICAL PRODUCTS, INC., Kingsport, Tennessee.
Get maximum stain resistance with TEXANOL A-S a new plasticizer from Eastman
Eastman CHEMICAL PRODUCTS, INC. CHEMICALS DIVISION, KINGSPORT, TENN. Subsidiary of Eastman Kodak Company SALES OFFICES: Eastman Chemical Products, Inc., Kingsport, Tennesseer I ^ H H H H H I H P b f r a i o ; Chicago; Cincinnati; Cleveland; Dallas; Detroit; Greensboro, North Cqrolina; Houston; New York City; Philadelphia; St. Louis. Western Sales Representative: Wilson & Geo. Meyej^A Company, San Francisco; Los Angeles; Salt Lake City; Seattle.
Chemical Labeling Encyclopedia of Chemical Labeling. I. MELLAN, E. MELLAN.
I l l pages.
Chemical Publishing Co., Inc., 212 Fifth Ave., New York, N.Y. 1961. $8.75. Reviewed by Dr. Thomas W. Nale. Dr. Nale is head of the industrial medicine and toxicology department at Union Carbide and is a member of the precautionary information committee of Manufacturing Chemists Association. Webster defines "encyclopedia" as a summary of knowledge. It is generally accepted that such a work is authoritative and factual. This is not true of this 111-page volume. It might more informatively be entitled an introductory handbook on the writing of precautionary labeling—warning labels—for chemicals. It consists of two parts. The first, on Background and Practice of Chemical Labeling, will serve to introduce the uninitiated to some of the principal governmental laws and regulations and industry labeling practices. The second part, on Classification of Labels for Safe, Accurate Labeling, attempts to suggest suitable labeling for a substantial number of chemicals. Unfortunately, the errors and omissions in both parts of this handbook are such that its chief value will be to serve as a lead to other more authoritative sources. In Part 1, Chapter 1, specific references are made to past federal legislation, but there is no mention of the Federal Hazardous Substances Labeling Act passed by Congress in 1960. This act is causing more concern in current labeling practices than any other recent labeling legislation. Also, there is no reference to the various state and local regulations affecting labeling practices. All of these must be considered in labeling hazardous chemicals. The sample Interstate Commerce Commission labels are not all accurate. In fact, several pi those presented are now obsolete (pages 28, 30, and 3 1 ) . The labels from British chemical manufacturers would not conform to accepted practice and regulatory requirements in the United States. In Part 2, Chapter 1, the general idea of a key to classification is satisfactory in providing certain uniform labeling statements for use when ap82
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plicable. Some of the statements are not widely used, however. The "Antidote and Treatment" statements go beyond present industry practice and governmental requirements and suggest treatment which is more safely left for the physician. Part 2, Chapter 2, contains many inaccuracies. In respect to flash points in degrees Fahrenheit, there is no indication as to which method was used in testing what chemicals. Most of the flash points given in the first several pages are actually from the closed oup method. Transportation and labeling regulations are generally based on the Tagliabue open cup values, so the flash points given are of little worth. The Federal Hazardous Substances Labeling Act also specifies the Tagliabue open cup method. The M.A.C. (p.p.m.) values are of little use in the preparation of labels. They refer to concentrations of substances in air considered safe (or comfortable) for eight-hour daily exposures. The term "M.A.C." is still used by the A.S.A. Z37 Committee for the limited number of values they have recommended, but in recent years such values have more generally been known as Threshold Limit Values. A revised list of these values is published each year by the American Conference of Governmental Industrial Hygienists. In Part 2, Chapters 2 and 3, it is noted that the authors have assigned an M.A.C. value for practically every chemical or substance listed. The majority of these chemicals have never had M.A.C. or T.L. values set for them by any recognized group. M.A.C. values in p.p.m. are also noted for dusts, fumes, and mists. These should not be listed in parts per million but in milligrams per cubic meter of air. It is also unfortunate that many of the values given are incorrect according to up-to-date lists. As examples, acetone is given an M.A.C. of 200 p.p.m., while the generally accepted value is 1000 p.p.m.; methyl alcohol is shown as 10 p.p.m., and the accepted value is 200 p.p.m. Among the dusts listed, there is an M.A.C. of 0.2 p.p.m. presented for coal dust. Coal dust is about as inert as any dust, and no such limit has ever been suggested. On the same page (86) beryllium is listed with a comparable M.A.C. of 0.2 p.p.m. Beryllium is highly toxic, and the actual Threshold Limit Value set for it is 0.002 milligram per cubic meter.
This tabulation has errors in respect to the ICC classifications. A number of chemicals which are listed by name in the Commodity List of the ICC Regulations, together with the proper labels, are listed in this encyclopedia with the wrong labels. The pertinent ICC Regulations were in effect on Sept. 25, 1960. These incorrect listings are noted in some 18 instances. Part 2, Chapter 3, Minor Classification of Less Hazardous Chemicals, J contains many chemicals which are quite hazardous. To mention a few of these: acetic anhydride, acetonitrile, acetaldehyde, ethylamine, isopropylamine, and beryllium compounds and salts. The glossary definition of "poison" is an old one from drug and pharmacy laws. It does not conform with the definition of a poison or a highly toxic substance as given by the ICC Regulations, the Federal Hazardous Substances Labeling Act, the Federal Insecticide Regulations, and many state regulations. This encyclopedia is incomplete and contains many inaccurate and misleading references, and therefore, in this reviewer's opinion, is not dependable for use as a guide in the preparation of precautionary labels for hazardous chemicals. The authors have failed to include a bibliography or adequate cross references.
New Revision for Hazardous Substance Labeling Issued Chemical Specialties Manufacturers Association has issued its second revision of "Compilation of Labeling Laws and Regulations for Hazardous Substances." The new edition includes 21 pages of federal and state regulations and statutory changes made during the past two years. It also includes the full text of the Federal Hazardous Substances Labeling Law. The book is free to CSMA members, with extra copies available at $2.00 each. For nonmembers the charge is $3.00. To receive revision 2, nonmembers must already have the basic compilation and the first revision. Complete issues of the compilation and the two revisions are $7.00 to members and $10 to nonmembers. Address orders to CSMA, 50 East 41st St., New York 17, N.Y.
BRIEFS Family Emergency Almanac, a 36-page booklet, has been prepared by National Safety Council and is available from NSC at 425 North Michigan Ave., Chicago 11, 111., in lots of 50 for 20 cents each, of 500 for 16 cents each. It is designed in the manner of the old fashioned family almanac and emphasis is on family safety, with details on accident causes and prevention.
Chemical
Safety
Data
Sheet
Table-top Hydrogen ultra-pure instantly
size Milton Roy Purifier produces hydrogen almost for lab studies.
SD-85
covers Properties and Essential Information for the Safe Handling and Use of Acrolein. It is available for 30 cents a copy from Manufacturing Chemists* Association, 1825 Connecticut Ave., N.W., Washington 9, D.C.
Safety in the Chemical Laboratory is
the title of a 16 mm. sound-color movie made by Manufacturing Chemists' Association, 1825 Connecticut Ave., Washington 9, D.C. Purpose is to aid educators and employers in fulfilling accident prevention responsibilities in laboratories. Purchase price is $100, or the film may be previewed for $10 a week.
British Sulphur Corp. is beginning publication of the third international journal in the series started with Sulphur in 1953 and continued with Nitrogen in 1959. The new journal, Phosphorus and Potassium, will be sold, like its predecessors, on a subscription basis at a price commensurate with the consultative nature of its marketing and technical content. It will be issued quarterly. Further information is available from the publicity manager, British Sulphur Corp., Ltd., 43 Great Marlborough St., London W.l, England.
Spectroscopy is the subject of a new periodical entitled Journal of Quantitative Spectroscopy 6- Radiative Transfer, which began publication last September. Publisher is Pergamon Press, Ltd., Headington Hill Hall, Oxford, England, or 122 East 55th St., New York 22, N.Y. Editor is S. S. Penner of Caltech. Subscription rate is $10 a year.
impure gas yields
ULTRA-PURE H 2 right in your lab!
(Impurities
are less than 10 parts per billion concentration)
When you need small quantities of bone-dry, ultra-pure hydrogen —instantly and at low cost—produce it right in your lab with a pint-size Milton Roy Hydrogen Purifier. With virtually instantaneous warm-up, this Serfass-designed unit gives you 99.9999-f% pure hydrogen from impure hydrogen sources. Any impurities present are in the parts-per-billion range. Our two table-top size models are specially designed for gas chromatography, flame photometry, as a standard, and for other applications requiring high purity hydrogen. Both models employ palladium-silver alloy membranes for greater stability and higher diffusion rates. Source gas, such as cylinder hydrogen, passes through this special alloy, which selectively separates hydrogen from all impurities including water vapor. This hydrogen is so pure that modern analytical techniques cannot detect impurities. Operation of these purifiers is simple and positive. The unit plugs into any convenient 115-volt, a-c outlet. Impure hydrogen connects to the inlet. Pressure and flow are adjusted to the proper operating range. Ultra-pure, dry hydrogen is collected at the outlet. The Model CL-A Purifier, 40 milliliters per minute capacity, and the Model CH-A Unit, with a 150 ml/min rating, are low in initial cost and cost little to operate. Other standard units are available in capacities up to 1,000 cubic feet per hour with capacities up to 10,000 cfh designed to meet specific customers' needs. Bulletin No. 1159-2 describes in detail the entire line of Milton Roy Hydrogen Purifiers. Send for your copy today. M i l t o n Roy C o m p a n y , 1 3 0 0 E. M e r m a i d Lane, Phila. 1 8 , Pa. Controlled Volume Pumps Hydrogen Purifiers Colorimetric Analyzers Laboratory Instruments
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