JCE Online Journal of Chemical EducationDivision of Chemical Education, American Chemical SocietyAmerican Chemical Society
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print

JCE Digital Library

JCE Software

Only@JCE Online

About JCE


 Home > Journal of Chemical Education > Issues > 2007 > August >
August 2007 Featured on the Cover
Teaching fluorescence. The cover features samples of polymer-embedded colloids of nanometer-sized cadmium selenide sulfide (CdSexS1−x), left two samples, and cadmium selenide (CdSe), right two samples, similar to those synthesized in general chemistry labs at the University of Iowa. When irradiated with light of energy greater than the band gap energy, these semiconducting colloids display band edge fluorescence. The light of the fluorescent emission has an energy (and associated color) that is approximately equal to the band gap energy of the material. When the samples are irradiated with ultraviolet light (λ = 365 nm), the emission colors range from violet to orange (bottom image). When green laser (λ = 532 nm) irradiation is added, only samples whose emission colors correspond to light of a lower energy than green light display significant fluorescence within the laser beam cross section (top image).

Photo is courtesy of Russell Larsen; the quantum dots were prepared by Jamie O’Meara.


The cover was designed by Betsy True.

 Home > Journal of Chemical Education > Issues > 2007 > August > Featured on the Cover


Search JCE Index
Search Title, Authors, Keywords for

Subscriptions

JCE HS CLIC

Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.


Contributions Welcome
JCE welcomes your submission

Advertisers
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.

Be An Ambassador
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.