Abstract: In one embodiment, a contact-surface determination apparatus includes processing circuitry. This processing circuitry acquires an image depicting a contact surface of a ultrasonic probe, and determines a state of the contact surface of the ultrasonic probe on the basis of the acquired image.

Abstract: A cylindrical container with a bottom has an opening in which a projection is installed, the projection having a shape which will not deform solder balls when inserted into a packed layer of solder balls within the container. Its shape is such that its cross section has a streamlined or inverted conical shape, or it is cylindrical with a tip having a semi-spherical or inverted conical shape. Blackening, electrical charging, and deformation of solder balls packed in the container can be prevented during transport.

Abstract: A pair of header plates securely brazed with a pair of side plates without causing any buckling to tubes and any deformation to the header plates. First, each tube is press-fitted into a corresponding press-fitting hole in the header plates, and at the same time, the end parts of a pair of side plates make contact with the pair of header plates. Second, flaring pins are press fitted into the end parts of the tubes in such a way that the end parts of the tubes disposed near either side of a core assembly are flared to an angle of approximately 180.degree. and the end parts of the tubes disposed in the central part of the core assembly are flared to an angle within a range from approximately 60.degree. to approximately 80.degree.. Third, cores, etc. are hung from either of the upper header plates, whichever is disposed at the upper side, and then this assembly is brazed. At this time, large widening parts with an angle of approximately 180.degree. can prevent the upper header plate from sliding downwards.

Abstract: In a solvent dewaxing process wherein a waxy hydrocarbon oil is mixed with a dewaxing aid and dewaxing solvent and chilled to form a slurry comprising solid particles of wax and a mixture of dewaxed oil and solvent, the improvement which comprises using a polymeric dewaxing aid comprising a condensation product of naphthalene and chlorinated wax having an average molecular weight ranging from about 20,000 to 500,000 and a molecular weight distribution exceeding the range of from about 10,000 to 1,000,000.

Abstract: In a solvent dewaxing process wherein a waxy hydrocarbon oil is mixed with a dewaxing aid and dewaxing solvent and chilled to form a slurry comprising solid particles of wax and a mixture of dewaxed oil and solvent, the improvement which comprises using a polymeric dewaxing aid comprising a condensation product of naphthalene and chlorinated wax having an average molecular weight ranging from about 20,000 to 500,000 and a molecular weight distribution exceeding the range of from about 10,000 to 1,000,000.

Abstract: An improved dewaxing aid for solvent dewaxing process comprising a mixture of (A) an .alpha.-olefin polymer having an average molecular weight of from about 10,000 to 1,000,000 and a wide molecular weight distribution exceeding the range of from about 10,000 to 1,000,000 but falling within the range of from about 2,000 to 3,000,000 and (B) an olefin-vinyl acetate copolymer having a vinyl acetate content of from about 15 to 40 wt.% and an average molecular weight of from about 50,000 to 1,000,000. The .alpha.-olefin polymer having a high molecular weight and wide molecular weight distribution, when combined with the olefin-vinyl acetate copolymer, synergistically improves the efficiency of wax separation.

Abstract: Dewaxing aid used in a solvent dewaxing process is recovered in wax bottoms from slack wax by vacuum distilling the slack wax to about 5-10 wt. % bottoms at a temperature no greater than about 320.degree. C. The dewaxing aid-containing wax bottoms is recycled back into the dewaxing process by adding same to the wax-containing oil feed in an amount ranging from about 0.5-5 wt. %. This has been found to be particularly advantageous when the dewaxing aid is an .alpha.-olefin copolymer, a chlorinated paraffin/naphthalene condensation product and mixture thereof because of their thermal stability.