Abstract: Mineral acid slurries of benzidine derivatives having high stability are provided by incorporating into such slurries a polysaccharide.

Abstract: A vaned diffuser disposed around an outer periphery of an impeller of a centrifugal compressor comprises a pair of diffuser plates which constitute side walls of the vaned diffuser and define therebetween a fluid channel, and a plurality of vanes arranged in the fluid channel defined between the diffuser plates. At least one rib is arranged on that surface area of at least one of the diffuser plates which is defined between the adjacent vanes, so as to improve condition of a fluid flowing through the vaned diffuser to thereby improve efficiency of the latter. The rib is of a height not larger than one-half the height of the vanes and has a leading edge located upstream of the leading edges of the vanes as viewed in a fluid flow direction.

Abstract: An electrophotographic developer containing a carrier, a resinous, waxy or varnish compound and as a color component, a phosphotungstomolybdic acid lake of a mixture of an indolenine dye of the formula (I): ##STR1## wherein A is a benzene or naphthalene nucleus, R.sub.1 is a C.sub.1 -C.sub.4 alkyl group R.sub.2 and R.sub.3 are respectively a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, R.sub.4 and R.sub.5 are respectively a hydrogen atom, a C.sub.1 -C.sub.4 alkyl, .beta.-hydroxyethyl, .beta.-chloroethyl, .beta.-cyanoethyl, aralkyl, cycloalkyl, phenyl, or substituted phenyl. Y is a hydrogen or halogen atom, or a nitro, alkyl, alkoxy, carbalkoxy or acetamido group, and X.sup.- is a colorless anion, with a xanthene dye of the formula (II): ##STR2## wherein R.sub.6, R.sub.7, R.sub.10, R.sub.11 and R.sub.12 are respectively a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, R.sub.8 and R.sub.9 are respectively a C.sub.1 -C.sub.4 alkyl group, and Y.sup.- is a colorless anion.