NEW PRODUCTS
do you want to measure radiant energy?
Modular instrumentation system con sists of eight modules for setting up three analytical instruments: a visi ble-range spectrophotometer, a filter colorimeter, or a nephelometer. The ChemAnal System was designed spe cifically for teaching purposes; the lids of several modules can be raised so that the user can observe the func
tion of significant parts. The spec trophotometer has a range of 3 5 0 to 625 Γτίμ, an accuracy better than ± 5 n y , and a bandwidth of 2 0 νημ. A 96-page instruction manual con taining eight typical experiments is provided. Welch Scientific Co., 7 3 0 0 N. Linder Ave., Skokie, III. 6 0 0 7 6 404
S a f e t y S h u t t e r s f o r X - R a y Tubes
Now you photochemists and photobiologists can measure radiant energy directly in ergs/cm'-/sec and milliwatts/ cm-. No need for complicated conversion tables and mathe matical gymnastics. The Model 65 YSI-Kettering Radiometer is wavelengthindependent with seven fullscale ranges from 2.5 χ 103 to 2.5 χ 10'1 ergs/cm'J-sec (0.25 to 250 m w / c m 2 ) . Readings are accurate to ± 5 % of full scale. Easy balance offset for up to 1.2 χ 10r' ergs/cm 2 -sec ambient radiation. Recorder output provided. Small, interchangeable ther mistor bolometer probe fits limited access areas. YSI 6551 probe has s t a n d a r d fused quartz window with a 0.25 to 3.3 micron range. Instrument and probe $385. Write for specifications.
YELLOW SPRINGS INSTRUMENT CO. YELLOW SPRINGS, O H I O 4 5 3 8 7 Circle No. 168 on Readers' Service Card
108 A
·
ANALYTICAL CHEMISTRY
Electric "Fail-Safe" shutters for both General Electric and Norelco x-ray tubes help prevent accidental exposure to the operator while adding to the flexibility and usefulness of the x-ray equipment. A warning light is mounted directly on the shutter and warns that the shutter is open at the source of x-rays. The shutter can only be opened manually. A shutter mounted on the x-ray window can be timed for differ ent exposures. The shutters have been designed to fit all types of x-ray tubes and come with a power supply timer which operates on 110-120 V ac. Elec tronics and Alloys, Inc., 145 S. Dean St., Englewood, N. J. 07631 405 C a r b o n Dioxide Laser
The Model 420 is a high-power C 0 2 laser which is rated at 40 watts mini mum and 50 watts typical output power at 10.6 microns. The laser has an efficiency greater than 10%. A unique optical system allows the beam to be focused to a point inside the laser housing itself. The sample chamber provides a convenient means of irradi ating small samples. Safety devices caution operators when high-power in visible radiation is emitted from the laser. Eimac Division of Varian, 30 Industrial Wav, San Carlos, Calif. 94070. 406
Differential thermal analysis system consists of a water-cooled furnace, equipped with chromel-alumel con trol and differential thermocouples, and an adjustable, solid-state power programmer-controller to give heating rates of 5, 10, and 2 0 ° C / m i n u t e to 1100° C. A meter relay monitors the temperature and selects the shut-off point on the Model DTA-A3. The Model DTA-A4 is the same as the DTA-A3 except for the use of plati num—10 % rhodium differential ther mocouples and a magnetic amplifier to compensate for decreased sensitiv ity of the thermocouples. Harrop Laboratories, 3 4 7 0 E. Fifth Ave., Co lumbus, Ohio 4 3 2 1 9 407
