log/linear this is aphotometer;
New Books
Here's an Instrument that can make the Gradient.
FOR CHROMATOGRAPHIC ELUTION OR FILLING ZONAL ROTORS With a c a p a c i t y of 3 2 0 0 ml/hr, t h e Model 3 8 0 DIALAGRAD Programmed Gradient P u m p is especially s u i t e d for f i l l i n g zonal rotors as well as f o r m ing liquid c h r o m a t o g r a p h i c e l u t i o n gradients a n d similar applications. Almost any two c o m p o n e n t gradient can be f o r m e d by simply s e t t i n g a series of dials. There are no cams t o c u t or m u l t i p l e solutions t o mix a t e s t i m a t e d c o n c e n t r a t i o n s . The shape of t h e curve is d e t e r m i n e d by s e t t i n g eleven 0 t o 1 0 0 % dials w h i c h represent t h e initial, f i n a l , and nine evenly spaced i n t e r m e d i a t e ratios. Thisgives 10 program intervals, each of w h i c h are a u t o m a t i c a l l y s u b d i v i d e d by five linear interpolations t o produce a smooth gradient. Calibrated flow rates f r o m 1 t o 3 2 0 0 ml/hr a n d program d u r a t i o n s f r o m 5 m i n u t e s t o 16 days a r e set w i t h positive stop switches. The DIALAGRAD will produce linear or curved gradients with equal accuracy a n d t h e program will be perfectly r e p r o d u c i b l e run after r u n . The i n s t r u m e n t takes b u t a f e w m i n u t e s t o program and requires no a t t e n t i o n d u r i n g a program r u n . For more i n f o r m a t i o n , please request Brochure DP 3 1 .
series to correlate information on physical methods in macromolecular chemistry that was previously scattered throughout the literature. I t will provide the scientist with the understanding needed to select the most useful method for his research problem. By focusing on the interpretation of experimental data, the contributors point out important features and principal limitations of the methods treated. Both synthetic and naturally occurring macromolecules are considered. Atlas of Mass Spectral Data, 3 Volumes. E. Stenhagen, S. Abrahamsson, and F. W. McLafferty, Editors. John Wiley & Sons, Inc., 605 Third Ave., New York, N.Y. 10016. 1969. $150
This Atlas is limited to low resolution mass spectra; these have been contributed by a large number of organizations or individual research workers. Although it has been possible to detect and remove from the file gross errors due to the incorrect name of the compound or the use of samples containing large amounts of impurity, several errors of this type may remain. The mass spectra in this Atlas have all been produced by electron-bombardment ionization; ionization through charge exchange or field ionization give mass spectra that generally are very different. A list of the sources of the mass spectra is given. In some cases the mass spectra have not been run by the organization or individual who supplied the numerical data; one contributor points out that part of the data supplied by him was collected from the literature. In the main section containing the full tabular data the compounds are arranged by the molecular weight calculated on the basis of the exact nuclidic masses of the most abundant isotopes. Tables of the atomic weights and natural isotopic abundances precede the tabular data. The compounds are also listed in the Register according to their elemental compositions. A copy of the Register is included in the back of each volume of the Atlas, as it is felt that the user will find it easier to locate a particular compound through initial reference to the Register.
Complexometry with EDTA and Related Reagents, 3rd Edition. T. S. West. 235 pages. BDH Chemicals, Ltd., Broom Road, Poole, Dorset, England. 1969. 50s
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This monograph surveys the reagents and techniques of complexometric titration with EDTA and endeavors to give as balanced a view of the area as possible. The indicators and masking
wave-form generator; potentiometer; pH meter; digital timer; integrator; conductometric titrator; differentiator; anodic stripping analyzer; pH stat, potentiostat and amperostat controller; null detector; A.C. & D.C. amplifier; comparator; chronopotentiometer; chronoamperometer;
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