THE EDITORS' COLUMN
2
THE EDITORS' COLUMN Α COMPUTER PROGRAM for the con- " ^ version of representations of chemical composition has been pre- pared by D. A. Stephenson of Corn- ing Glass Works. Because the con- version of representations of chemi- cal compositions—e.g. weight per cent oxides to atomic per cent ele- ments—is a long, tedious process subject to numerous computational errors when large numbers of sam- ples are involved, a Fortran com- puter program has been written that will perform the necessary cal- culations. The program converts any one of the ten representations of chemical composition listed be- low into any or all others. • Weight per cent compounds • Mole per cent compounds • Parts per million (by mole) of the compounds •Parts per million (by weight) of the compounds • Weight per cent elements • Atomic per cent elements •Parts per million (atomic) of the elements • Parts per million (by weight of the elements • Grams of the compounds • Grams of the elements In addition, the program may be used to calculate the required weight of either compounds or ele- ments necessary to constitute a sample of specified weight from data entered as any of the listed representations. This is useful in preparing standards for various in- strumental methods of chemical analysis. The program accepts up to 20 compounds or 25 elements per sam- ple. Nine hundred ninety-nine samples containing the same com- ponents may be processed at one time and jobs involving samples INSTANT FIRST AID FORM When dangerous acids, alkalies, or particles contact the eyes and face, HAWS instant first aid re- sponds at a touch! Controlled and localized streams flood contami- nants down the drain to prevent per- manent injury. Write for HAWS free "First Aid on Tap!" catalog today. EMERGENCY EYE/FACE-WASH FOUNTAINS WHÈ Since 1909 HAWS DRINKING FAUCET CO. 1443 Fourth Street Berkeley, California 94710 Also manufacturers of emergency drench showers, drinking fountains and water coolers. Circle No. 121 on Readers' Service Card continuous Monitoring ol Cas Flow with FLOW-MATE •tat ® » e ^ m a t ^ r o ( i h y , where careful optimization of ftow rate is essential to achieve precise accuracy, use of the FLOW-MATE éliminâtes the inconven- ience of conventional bubble flow- meters. It provides greater accuracy than the rotameter and is not subject to sticking or bouncing. A continuous device with accuracy equivalent to the bubble meter, the FLOW-MATE functions independently of the operator's skill. The specially designed T.C. cell con- tains two thermistor elements in a Wheatstone bridge. Temperature com- pensated over normal lab variations, it obviates constant zero checking. FL0W- Select the model and "opflt^s",, ,. suited for your application; Models may be calibrated for either 0-100 cc/min. or 0-1000 cc/min. range. Calibration curves for helium are supplied. Curves for other gases normally used in G.C. analysis can be furnished on request. Potentiometric recorder readout is standard; direct meter readout is op- tionally available. Battery or line oper- ation may be specified. Prices range from $150. to $210. GOW | MAC 100 KINGS RD., MADISON, N.J. 07940 TELEPHONE: (201) 377-3450 Circle No. 116 on Readers' Service Card VOL 40, NO. 7, JUNE 1968 · 75 A eves face Model 7760-BT &
Transcript of THE EDITORS' COLUMN
THE
EDITORS'
COLUMN Α COMPUTER PROGRAM for the con-
" ^ version of representations of chemical composition has been prepared by D. A. Stephenson of Corning Glass Works. Because the conversion of representations of chemical compositions—e.g. weight per cent oxides to atomic per cent elements—is a long, tedious process subject to numerous computational errors when large numbers of samples are involved, a Fortran computer program has been written that will perform the necessary calculations. The program converts any one of the ten representations of chemical composition listed below into any or all others.
• Weight per cent compounds • Mole per cent compounds • Parts per million (by mole) of the compounds •Par t s per million (by weight) of the compounds • Weight per cent elements • Atomic per cent elements •Par ts per million (atomic) of the elements • Parts per million (by weight of the elements • Grams of the compounds • Grams of the elements In addition, the program may be
used to calculate the required weight of either compounds or elements necessary to constitute a sample of specified weight from data entered as any of the listed representations. This is useful in preparing standards for various instrumental methods of chemical analysis.
The program accepts up to 20 compounds or 25 elements per sample. Nine hundred ninety-nine samples containing the same components may be processed at one time and jobs involving samples
INSTANT FIRST AID
F O R M
When dangerous acids, alkalies, or particles contact the eyes and face, HAWS instant f irst aid responds at a touch! Controlled and localized streams flood contaminants down the drain to prevent permanent injury. Write for HAWS free "First Aid on Tap!" catalog today.
EMERGENCY EYE/FACE-WASH FOUNTAINS
WHÈ Since 1909 HAWS DRINKING FAUCET CO.
1443 Fourth Street Berkeley, California 94710 Also manufacturers of emergency drench showers, drinking fountains and water coolers.
Circle No. 121 on Readers' Service Card
continuous Monitoring ol Cas Flow with FLOW-MATE
•tat ® » e ^ m a t ^ r o ( i h y , where careful optimization of ftow rate is essential to achieve precise accuracy, use of the FLOW-MATE éliminâtes the inconvenience of conventional bubble flowmeters. It provides greater accuracy than the rotameter and is not subject to sticking or bouncing. A continuous device with accuracy equivalent to the bubble meter, the FLOW-MATE functions independently of the operator's skill.
The specially designed T.C. cell contains two thermistor elements in a Wheatstone bridge. Temperature compensated over normal lab variations, it obviates constant zero checking. FL0W-
Select the model and "opflt^s",, ,. suited for your application; Models may be calibrated for either 0-100 cc/min. or 0-1000 cc/min. range. Calibration curves for helium are supplied. Curves for other gases normally used in G.C. analysis can be furnished on request. Potentiometric recorder readout is standard; direct meter readout is optionally available. Battery or line operation may be specified. Prices range from $150. to $210.
GOW | MAC 100 KINGS RD., MADISON, N.J. 07940
TELEPHONE: (201) 377-3450
Circle No. 116 on Readers' Service Card
VOL 40, NO. 7, JUNE 1968 · 75 A
eves face Model 7760-BT
&
EDITORS' COLUMN
with different components m a y be stacked.
The logic embodied in the program is to transform whatever representat ion is entered as da ta into atomic per cent elements and to compute the desired representation (s) from this basis. Symbols and atomic weights of the elements used by the program are those accepted by the I.U.P.A.C. (1964).
The program has been writ ten in For t r an 4 (Η-level subset) for the I B M 360 computer. Other machines a n d / o r compilers may require t h a t I / O sta tements be modified and certain logical s ta tements be rewrit ten. I t requires 55,898 decimal storage locations. Source a n d / o r object decks, along with detailed instructions, m a y be obtained from the author a t Research and Development Laboratories, Corning Glass Works , Corning, Ν . Υ.
Certified Gas Standards
This month 's Repor t for Analyt i cal Chemists, "An Analyst ' s View of Our Polluted P lane t , " by D r . Ra lph G. Smith, contains much interesting information about the needs of and pitfalls for scientists engaged in air and water pollution work. I t is gratifying to note t h a t this month the Nat iona l Bureau of Standards has announced new certified gas s tandards (see ρ 117 A) t h a t will lead the way for a series of s tandards for atmospheric constituents t ha t are troublesome from the air pollution standpoint . The C 0 2 in nitrogen s tandard was developed a t the request of the Environmental Science Service Administrat ion for use with instrumental methods for determining CO2. A par t ia l result of this program has already resulted in the development of a new mass spectrometric method t h a t permits determination of C 0 2
in the atmosphere a t levels previously una t ta inable [see A N A L . C H E M , 40, 750 (1968)] . Fu tu re work a t NBS will center on preparing s tandards for such atmospheric pol lutants as sulfur dioxide, carbon monoxide, and hydrocarbon gases. -< Circle No. 24 on Readers' Service Card
The keys to Log & Exponential
power
...exclusively on WANG
electronic calculators
Wang's unique approach to data manipulation (a revolutionary electronic circuit which digitally generates the natural logarithm of any number entered) reduces complex calculations to simple, logical keystrokes and eliminates from 67 to 93 per cent of calculation time.
On keyboard displays, about the size of a telephone, all basic arithmetic functions ( + , —, x , -*- , 7 ) are performed silently, in milliseconds. Optional keys produce X2, VT, Logex, e* by a single keystroke. (For unmatched economy, up to 4 keyboards can operate simultaneously from a briefcase-
size electronics package located up to 200 feet away.)
Other options include: 4 additional random-access storage registers (two are standard), 80 step, plug-in card programmer and/or built-in programs for single keystroke calculations of sin Θ, cos Θ, arcsin x, arctan x.
Add-on compatibility makes it possible to expand into a powerful computing system that will branch, loop, do sub-routines, make decisions and manipulate arrays. There is nothing comparable, anywhere. For complete information, write or call:
WANG L A B O R A T O R I E S , I N C .
Dept. 6Y 836 North St., Tewksbury, Massachusetts 01876 · Tel. 617 851-7311
In Major (201) 241 (203) 666· (205) 245 (206) 622 (212) 682 (213) 278 (214) 361
Cities, Tel: •0250 (215) 9433 (216) 6057 (301) 2466 (301) •5921 (303) 3232 (305) 4351 (312)
642-4321 333-6611 588-3711 821-8212 364-7361 841-3691 456-1542
(313) (314) (317) (319) (402) (404) (405)
278-4744 727-0256 631-0909 365-2966 341-6463 457-6441 842-7882
(412) 366-1906 (415) 454-4140 (416) 364-0327 (504) 729-6858 (505) 255-9042 (512) 454-4324 (513) 531-2729
(514) 482-0737 (518) 463-8877 (601) 234-7631 (612) 881-5324 (614) 488-9753 (617) 851-7311 (702) 322-4692
(702) (713) (714) (716) (717) (816) (817) (919)
735-5802 668-0275 234-5651 381-5440 397-3212 421-0890 834-1433 288-1695
Circle No. 163 on Readers' Service Card
VOL. 40, NO. 7, JUNE 1968 · 77 A
