Model DU DU spectrophotometer

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disassembled absorption cell , photo-tube compartment, cary & beckman, 1941


when rca not meet beckman s demand experimental phototubes, national technical laboratories again had design own components in-house. developed pair of phototubes, sensitive red , blue areas of spectrum, capable of amplifying signals received. incorporation of beckman s uv-sensitive phototubes, model d became model du uv-vis spectrophotometer. designation uv-vis spectrophotometer indicates ability measure light in both visible , ultraviolet spectra.


the du first commercially viable scientific instrument measuring amount of ultraviolet light absorbed substance. had done ph meter, beckman had replaced array of complicated equipment single, easy-to-use instrument. 1 of first integrated instruments or black boxes used in modern chemical laboratories, sold $723 in 1941.


it assumed du in name combination of d model d on based, , u ultraviolet spectrum. however, has been suggested du may reference beckman s fraternity @ university of illinois, delta upsilon, members called du s.


a publication in scholarly literature compared optical quality of du cary 14 spectrophotometer, leading uv-vis spectrophotometer of time.








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