MEMO TO: AU GC Users

FROM: Matheson 'technical Service

SUBJECT: Improved GC Results

Ί In· wi lue <ιΓιι-:ιηκ liigh p i i m y e a r n e r tiases tr> improve (,C :ui.il\ti«-;i1 rer-ulu i- u e l l known. ()Π ι·(ΐ foruol lcn is t in· t r ans fe r .- \siein lo del iver I hi- «;i- Γηιΐη I hi- cy l inder ti> t he in - t run ien i wi ihimi in t rnducint i impur i t i e s t h a i I'oulcl .-ΙΠΊΊΊ resu l t - .

Λ ki-> to <i Iiif.h pu r i t y traiir-Ier - \ > | Ι Ί Ι \ i.-. I hi- M a t h e s o n : i l01 p R ^ s u r c r egu la to r . Γι lealure.- i n » siajje des ign , a s t a m l e - s M i d d i a p h r a g m and a diaplir:iRm pack It·.-.- v a h e . Tlit· M a m l e - s steel d i a p h r a u m and .-pecial lli(,'h p u r i U d i a p h r a g m pack less \ a l i e prnler l iiK:iin.-i diffusion ol' impur i t i e s «uch a- o.\\-lien. w a t e r and l n d n i c n r h o n - . iiiin ι lie μ: ι< s t r e a m . Such impur i t i e s can add in a n a h t i c a l inaccuracie,- by inc reas ing ha -e l ine noise anil i l e l e r in ra l ing co lumn packing.-.

ΓηίΙΊιιτη sa.- flow a n d i o n - t a i n ca r r i e r L.':I.-pler-sure in your m«l run ien l u ill also help to eiisiire be t to r r esu l t s . T h e .'J101 r egu l a to r i-di-.-iKMi'ii w i th a la rne <,en-dri\e -ecniul s la - i -d i a p h r a g m m pirn ide stead> μ.·ι> <.Uliver> and precise p r e s su re control ;u h i^h or !i>u How-..

The del ivery p r e s s u r e r a i l l e i-l 100 ρ.-ίμ' ιιΓ I lie •') 104 Κ ideally su i ted In nio-l f.iC app l ica t ions . The de l ivery pres.-ure « a u ^ e r a i l l e is 0 ii()0 p-ie,. T h e Ό )¥)()<> p^-ιμ c\ Under p r e s su re tfiui^e monitor · · c a r r i e r g a - cyl inder I'unteiil -.

T a k e an impuriai i l s tep inward he l l e r <•(' r e su l t s t "dny . I-'ind oui more alioul t h e Mathesun ,'ÎIOI ( iC r egu la to r .

For fur ther informal inn cniitacl \ iu i r local Mathe.-on b ranch oi circle t h e Header Service N u m b e r lielnw,

Do thi· CCjoh ημίιΐ!

Matheson •'JO Seavieu. Drive, Secaucus , N.J 0700.1 j , '

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Briefs

Determination of Volatile Organic Compounds in Fish Samples by Vacuum Distillation and Fused Silica Capillary Gas Chromatography/Mass Spectrometry

506 V a c u u m dist i l la t ion provides a concent ra te readily t ransfer red t h rough the fused silica capil lary column wi th m i n i m u m carrier gas flow. Examples of volati le organic compounds de tec tab le in fish t issue dist i l la tes are provided. Michael H. Hiat t , U.S. Environmental Protection Agency, Region 9, San Francisco, Calif. 94105 Anal. Chem., 55 (1983)

Production and Certification of Sulfur in Gas Oil Reference Materials 516 C o m m u n i t y B u r e a u of Reference R M s 104 ,105 ,106 , a n d 107 are certified to contain 0.091 ± 0.002, 0.363 ± 0.010, 0.502 ± 0.008, and 1.040 ± 0.015 mass fraction percen t sulfur, respectively. Alan S. Lindsey and Pe te r J . Wagstaffe*, Community Bureau of Reference, BCR, Commission of the European Communities, Rue de la Loi 200, B-1049 Brussels, Belgium

Anal. Chem. ,55 (1983)

Differential Pulse Polarography for a First-Order Catalytic Process 522 R a t e cons tan t s for t he T i 4 + / N a C 1 0 3 a n d T i 4 + / N H 2 O H catalyt ic redox sys tems are 6.1 X 1 0 - 4 s - 1 M - 1 a n d 4.6 X 1 0 1 s _ 1 M _ 1 , respectively, a n d are in ag reemen t wi th r epor t ed values de t e rmined by dc a n d ac polarographic m e t h o d s . Myung-Hoon Kim and Ronald L, Birke*, Department of Chemistry, The City College, City University of New York, New York, N.Y. 10031 Anal. Chem., 55 (1983)

Laser Microprobe Mass Analysis Studies on Coal and Shale Samples 527 Laser - induced desorpt ion wi th a low angle-of-incidence p h o t o n b e a m produces cat ions from minera l inclusions, and anion a d d u c t s from volati le hydrocarbons . Nicholas E. Vanderborgh* and C. E. Roland Jones , Earth and Space Sciences Division, Los Alamos National Laboratory, Los Alamos, N.M. 87545 Anal. Chem., 55 (1983)

Automated Multicomponent Analysis with Corrections for Interferences and Matrix Effects 532 T h e generalized s t a n d a r d add i t ion m e t h o d is a u t o m a t e d wi th a computer -cont ro l led visible l ight spec t rophotometer . S t a n d a r d addi t ions are m a d e by weight r a the r t h a n by volume. J . H. Kalivas and B. R. Kowalski*, Laboratory for Chemometrics, Department of Chemistry BG-10, University of Washington, Seattle, Wash. 98195 Anal. Chem., 55 (1983)

CIRCLE 139 ON READER SERVICE CARD

352 A · ANALYTICAL CHEMISTRY, VOL. 55, NO. 3, MARCH 1983