Micro DTA @ -DSC in 1instrument? EPIT0 R S ' COLUMN I n THE ARTICLE "Analytical Chemistry in Yugoslavia," [ANAL. CHEX.,41 (8),24 A (1969)], it was stated that the Cniversiky of Belgrade is the oldest university (about 100 years) in the country. Several letters from Yugoslavia have pointed out t h a t while the University of Belgrade celebrated its centennial a few weeks ago, the tercentennial celebration of the University of Zagreb is being held in 1969. The University of Zagreb has existed by t h a t name only since 1874, but its origins can be traced t o 1662 when Jesuits founded a collegiate institute of philosophy in that city. The tercentennial celebration marks the elevation of that institute by Kaiser Leopold I of Austria-Hungary in 1669 to the rank of a faculty of philosophy. The modern definition of a university requires the existence of four faculties, and confusion often arises as to whether the founding date refers to the origin of the antecedent institution or of the fullfledged university. As for the early history of chemistry in Croatia, 8. Niholic, in Bulletin Scientifique, 3 ( 2 ) ) 33, states, "One can almost say that the alchemistic period in chemistry lasted in Croatia till the middle of the 19th century. The only other experimental work in chemistry was the number of analyses of Croatia mineral waters made by apothecaries, of which some are remarkably well done. The opening of the first technological middle school in Zagreb in 1864 marked the beginning of a new era. In 1866 the first course of experimental chemistry was delivered a t that school by Canon J. Torbar (1824-1900) physicist and later president of the Yugoslav Academy of Sciences. From 1859 the course in chemistry was given by P. Zulic, who wrote the first textbook of chemistry (1866). A further step was made when the University of Zagreb was
The fourth generation micro thermal analyzer developed by Professor Mazieres of the University of Paris is now available in the U.S. through the Infotronics sales and service organization. The M-4 DTA measures temperature differentials in the -160°C to 1600°C range with 0.1"C resolution. Temperature is programmed by a front panel switch at rates of 1°C to 20"C/min. Full atmospheric control is maintained with inert gas in the sample cavity. But that's only part of the story. The M-4 also functions effectively as a differential scanning calorimeter-without the use of special cells. Quantitative measurements can be obtained with excellent accuracy and with little Key to the M-4's sensitive performance for DTA and DSC lies in its patented probe design which features three hollow thermo-
Applications include all phases of organic and inorganic chemistry, such as polymers, elastomers. crystallography, ceramics, metallurgy, and quality control of feeds, foods and pharmaceuticals. To learn more, write for Data File DTA-4. INFOTRONICS CORP.
1062 Linda Vista Avenue Mountain View, California 94040
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It’s been more than a year since we introduced our Moduline 1800 Series Gas Chromatographs and still nobody’s been able t o match their versatility or performance. duline 1800 Series offers a choice te temperature programmers and ctors. A uniquely designed JFET eter comes standard on every instruoes a column oven w i t h 1090 cubic es of usea le space. And a greatly simplified For a rather convincing demonstration of uline 1800 Series GC’s, contact Varian erograp lreek, Ours. Ca1iforn ia
rian aetpmraw WALNUT CREEK, CALIFORNIA 94598
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established in 1874. The first professor of chemistry A. Velkov appointed in 1875, and a laboratory of chemistry opened in 1876.”
MOLECULAR MOVEMENT STUDIED BY LASER
Two scientists from the Akron University’s Institute of Polymer Science have reported a t the na‘tional meeting of the Society of Rheology (St. Paul, Minn., Oct. 1922) the development of a laser device for measuring molecular movement. Coherent red light from a sixfoot laser kube is passed through a solution of polymer macromolecules, whereupon a Doppler shift occurs that is detected by a photoelectric cell. Circuitry developed by the researchers, Dr. J. E. Frederick and Thomas F. Reed, filters noise and separates and records various frequencies and their harmonies. T h e laser tube for the apparatus is mounted on a one-ton concrete slab supported by steel “I” beams, and the entire system of laser tube, glass vessel for sample, and photocell are supported on heavy springs to absorb vibrations above 10 Hz. We are encouraged to remark that although the implementation of laser devices in analytical and associated instrumentation has been slow, there are a t least encouraging signs t h a t progress is being made, however deliberate bhe pace continues.
NEW MASS SPECTROMETER
A new mass spectrometer which weighs less than 2 oz, using three mesh electrodes has been developed by General Electric. Ions in gases are sorted according to their masses in the three-dimensional quadrupole electric field inside the electrodes, and a electron multiplier device is used to measure the number of trapped ions. Further information vi11 appear in a later issue.
No sacrifice in response or efficiency. Choose a Sargent combination pH electrode by size alone.
Both of these Sargent combination pH electrodes cover the entire pH range from 0 t o 14 pH. Both offer fast, linear responseeven in highly acid solutions. Response t o alkali ions is insignificant below pH 12.5 (at higher pH, response is low and stable). Both electrodes achieve high efficiency, with a millivcItipH response close to the Nernst coefficient. And you get this kind of performance over a range of 0 to 80°C. These electrodes also feature all-glass, shock-resistant construction. No rubber or plastic to contaminate samples. No pockets to trap solutions or hamper cleaning. Stainless-steel caps provide sure, strong ciarnping. What’s the d i f f c h n c e , then, between these two combination p H electrodes? Size alone. For samples as Small as V2 ml or those in extremely confined volumes, choose the miniature electrode (priced at $42.00). Otherwise, your best choice is the standardsize ($40.00). Both come with connecting cable and plugs to fit all popular pH meters. Call your Sargent man or write to us for a closer look at these combination pH electrodes or for data on our complete line of glass and reference electrodes.
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Scientific instruments, apparatus, chemicals. Sargent-Welch Scientific Company 7300 N . Linder Ave.; Skokie, Illinois 60076 Chicago!Anaheim!Birmingham/Cincinnati ClevelandiDallas:DenveriDetroit Springfield, N.J./Toronto/Montreal/Vancouver 7.90,
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