Abstract: Automatic titration analysis apparatus includes a sampling mechanism, a titration mechanism, an analysis mechanism and a control mechanism. The sampling mechanism takes a prescribed quantity of a sample for analysis in accordance with a first signal. The titration mechanism titrates a prescribed quantity of a reagent for analysis of the sample and provides a titer at an end point of the titration according to second signals. The analysis mechanism receives the sample from the sampling mechanism, analyzes the sample and converts a change in the physical properties of the sample caused by the titration into an electrical quantity.

Abstract: An electrophotographic copying apparatus comprises a photoconductive drum, a charger for electrically charging the drum, an exposure unit for exposing the drum to form a latent image on the drum which correspond to the pattern of a document, a developer unit for developing the latent image, using one-component toner, a transfer unit for transferring a toner image to a paper sheet and a fixer unit for fixing the toner image.In copying the document pattern, a document density-copy density characteristic, i.e. .gamma. characteristic, is set in accordance with the document density. According to the .gamma. characteristic the amount of exposure and the bias voltage to be applied on the developer unit are varied.