Abstract: An oil treating agent of W/O emulsion, wherein an aqueous dispersed phase is dispersed in an oily continuous phase, and wherein the dispersed phase is an alkaline mixture solution obtained by mixing water, a solution comprising water and an alcohol, or a water-free alcohol solution with an alkali hydroxide e.g. sodium hydroxide or with a metal alkoxide e.g. sodium alkoxide and the continuous phase comprises a liquid incompatible with the dispersed phase.

Abstract: A liquid concentration detecting apparatus which permits a real-time and high-accuracy detection of concentration of a liquid (particularly an etching or cleaning solution) used in a semiconductor plant, with a simple configuration at a low cost. The liquid concentration detecting apparatus 1 has a cell 2 to which a liquid is supplied, and a projecting section 4 and a receiving section 5 arranged opposite to each other in a direction at right angles to the axial line of the cell. A light of a prescribed wavelength is projected from this projecting section 4 through the liquid in the cell 2 to the receiving section 5, and the concentration of the liquid is determined by detecting the amount of light received by the receiving section.

Abstract: An optical liquid sensor comprises an optical fiber folded back in two, a light-emitting element disposed at one end of the optical fiber, a light-receiving element disposed at the other end, and a detection means comprising a pair of units of a rod lens and/or large-diameter glass optical fiber with a narrow gap interposed therebetween in a linear segment of a folded-back portion of the optical fiber, the folded-back portion being hermetically sealed except at an aperture portion for admitting a liquid into the narrow gap. In this sensor, the loss of light at the narrow gap is minimized. In the manufacture of the sensor, a special jig is used for insuring that a rod lens or the like is accommodated in a metal sheath in such a manner that its forward end is flush with the end face of the sheath or projects slightly beyond the end face.

Abstract: The present invention relates to a liquid leakage detector line for detecting the leakage, if occurs, of a liquid such as sulfuric acid or strong alkali from a transportion pipe line or a storage tank. The liquid leakage detector line comprises: a pair of wiry electrodes each including a conductor covered with an insulator layer made of macromolecular material including an ester bond, the wiry electrodes being disposed substantially in parallel with each other; and a liquid-absorbent material covering these wiry electrodes. The liquid-absorbent material may be a braided body layer made of liquid-absorbent yarn which is disposed outside of the pair of wiry electrodes, or may be a braided body layer similar to the first-mentioned braided body layer which is disposed at the outer periphery of each of the wiry electrodes. If a sulfuric acid or alkali liquid leaks, the liquid-absorbent material covering the wiry electrodes absorbs such leakage liquid.

Abstract: A lubricating oil for diesel engines is disclosed. This oil is based on a mixture of lubricating mineral base oil and a highly aromatic light base oil, and is highly effective in reducing the wear of the diesel engine designed to run with heavy fuels having high carbon to hydrogen ratios. The oil is also advantageous in that it does not clog the lubricant filter.