Abstract: An optical assaying method and system having a movable sensor is described. In one aspect, the present invention is a sensing system having a rotating sensor disk coated with indicator dyes sensitized to a variety of substances. In this configuration the sensing system further includes a detector for sensing spectral changes in light received from one or more of the indicator dyes. In another aspect, the present invention is a sensing system having a surface plasmon resonance sensor disk having grooves extending radially from a center of the disk. In yet another aspect, the present invention is a sensing system including a diffraction anomaly sensor disk having a dielectric layer that varies in thickness. The present invention allows for construction of an inexpensive sensing system that is capable of easily detecting a variety of substances either in a sample or a surrounding environment.

Abstract: An optical assaying method and system having a movable sensor is described. In one aspect, the present invention is a sensing system having a rotating sensor disk coated with indicator dyes sensitized to a variety of substances. In this configuration the sensing system further includes a detector for sensing spectral changes in light received from one or more of the indicator dyes. In another aspect, the present invention is a sensing system having a surface plasmon resonance sensor disk having grooves extending radially from a center of the disk. In yet another aspect, the present invention is a sensing system including a diffraction anomaly sensor disk having a dielectric layer that varies in thickness. The present invention allows for construction of an inexpensive sensing system that is capable of easily detecting a variety of substances either in a sample or a surrounding environment.

Abstract: A black donor for use in a laser addressable thermal transfer system, wherein the black donor comprises a substrate having coated thereon at least one black color layer comprising a binder and colorants. The colorants include a non-infrared absorbing black dye or pigment and about 10% to about 50% of a carbon black pigment, based on the total weight of the colorants in the black color layer.

Abstract: An optical assaying method and system having a movable sensor is described. In one aspect, the present invention is a sensing system having a rotating sensor disk coated with indicator dyes sensitized to a variety of substances. In this configuration the sensing system further includes a detector for sensing spectral changes in light received from one or more of the indicator dyes. In another aspect, the present invention is a sensing system having a surface plasmon resonance sensor disk having grooves extending radially from a center of the disk. In yet another aspect, the present invention is a sensing system including a diffraction anomaly sensor disk having a dielectric layer that varies in thickness. The present invention allows for construction of an inexpensive sensing system that is capable of easily detecting a variety of substances either in a sample or a surrounding environment.

Abstract: A black-and-white, negative-acting, silver halide emulsion is described which gives improved image tone when used in a photographic element. The toning agents are based on dithio-substituted compounds having the following general structures: ##STR1## where R.sub.1 and R.sub.2, independently, are selected from the group consisting of alkyl, aryl and heterocyclic groups, or R.sub.1 and R.sub.2 together complete a ring;n and m are integers from 1 to 5; Y is a hydrogen; R.sub.3 is a hydrogen or alkyl group;and X is selected from the group consisting of O, S, N--OH and N--N(R).sub.2, where R is a hydrogen or alkyl group.

Abstract: 2-Methyl-4,4a-dihydro-3H-carbazolium salts that are useful as dye precursors and dyes derived from those precursors are disclosed. The salts are described by the formula ##STR1## wherein R.sup.1 represents an alkyl, aryl, sulfoalkyl, carboxyalkyl, sulfatoalkyl, alkoxyalkyl, acyloxyalkyl, dialkylaminoalkylene, cycloaminoalkylene, acyl, or alkenyl group having from 1 to 18 carbon atoms; R.sup.2 represents an alkyl group having up to 18 carbon atoms; R.sup.3 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R.sup.4 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R.sup.5 represents hydrogen, nitro, carboxyl, sulfo, hydroxy, halogen, phospho, or an alkoxy, thioalkoxy, oxyalkyl, acyl, alkyl, aryl, or amino group having up to 18 carbon atoms; wherein any two groups R.sup.5, or R.sup.4 and a group R.sup.5, or R.sup.1 and R.sup.

Abstract: 2-Methyl-4,4a-dihydro-3H-carbazolium salts that are useful as dye precursors and dyes derived from those precursors are disclosed. The salts are described by the formula ##STR1## wherein R.sup.1 represents an alkyl, aryl, sulfoalkyl, carboxyalkyl, sulfatoalkyl, alkoxyalkyl, acyloxyalkyl, dialkylarinoalkylene, cycloaminoalkylene, acyl, or alkenyl group having from 1 to 18 carbon atoms; R.sup.2 represents an alkyl group having up to 18 carbon atoms; R.sup.3 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R.sup.4 represents hydrogen or an alkyl group having from 1 to 18 carbon atoms; R.sup.5 represents hydrogen, nitro, carboxyl, sulfo, hydroxy, halogen, phospho, or an alkoxy, thioalkoxy, oxyalkyl, acyl, alkyl, aryl, or amino group having up to 18 carbon atoms; wherein any two groups R.sup.5, or R.sup.4 and a group R.sup.5, or R.sup.1 and R.sup.