| http://www.w3.org/ns/prov#value | - Some of these difficulties, such as particle settling, particle clustering, color change by heat, and reduction of off-state optical density have been solved by R. L. Saxe (U.S. Pat. Nos. 3,756,700; 4,247,175; 4,273,422; 4,407,565; and 4,422,963), F. C. Lowell (U.S. Pat. No. 3,912,365), and R. I. Thompson (U.S. Pat. No. 4,078,856).
|
