Abstract: The cleaning apparatus of the present invention comprises a cleaning member 105 adapted to be rotated while maintaining contact with a surface of a semiconductor wafer W, to thereby clean the surface of the semiconductor wafer W, and a drive motor 50 for rotating the cleaning member 105. A linear bushing 75 and coil springs 81 are provided between the cleaning member 105 and the drive motor 50. The linear bushing 75 ensures that the cleaning member 105 is capable of slidably moving in a direction of an axis of rotation. The coil springs 81 ensure that the cleaning member 105 applies a predetermined pressure to the semiconductor wafer W. A pressure in a casing 1 [(1-1), (1-2) and (1-3)] is set to a negative pressure relative to an outside air pressure by suction through a pipe 111.

Abstract: A vacuum ionization gauging tube, particularly a Bayard-Alpert (B-A) type vacuum ionization gauging tube, has a firmly compact construction, and provides the capabilities for minimizing outgassing gases and measuring pressures accurately without affecting the ultimate pressure range. The B-A vacuum ionization gauging tube includes a filament having a total surface area of between 6 mm.sup.2 and 20 mm.sup.2, a grid formed like a coil from a 0.1 mm to 0.3 mm diameter metal wire, the coil having a diameter of 5 mm to 7 mm and a length of 15 mm to 20 mm and across which it can be energized, an ion collector electrode having substantially the same length as the filament, and a metal envelope for enclosing the above electrode elements and which is maintained at a potential lower than that of the filament. The grid coil has a winding pitch of between 1.5 mm and 2.5 mm. The filament and grid are spaced apart from each other by the distance of between 2 mm and 4 mm.

Abstract: This invention relates to 1,8-naphthyridine compounds of the formula ##STR1## wherein X is a halogen atom especially fluorine atom,R.sub.1 is an ethyl group or a vinyl group, andR.sub.2 is a hydrogen atom or a lower alkyl group, their salts and processes for the preparation of them.The 1,8-naphthyridine compounds and their salts are useful as antibacterial agents and intermediates thereof.

Abstract: Two fixed blades are provided at substantially right angle with each other with a juncture line thereof being in the transverse direction and opposite to the terminal end of a feeding conveyor passage of a sheet material to be cut. Two movable cutter blades are also provided at substantially right angle with each other opposite to the fixed blades in such a manner that one cutter blade coacts with one fixed blade and the other cutter blade coacts with the other fixed blade to cut the sheet material at substantially right angle with respect to the plane of the sheet material. The two movable cutter blades are made to alternately advance and retreat at a predetermined timing.

Abstract: Folic acid and related compounds are assayed by competitive radio-assay using a selenium - 75 labelled version of folic acid as the competing compound.

Abstract: A drilling bit for use in making a taphole in a blast furnace. The drilling bit has a bit head having a plurality of cutting tips radially arranged on and soldered to the bit head. Soldering of the tips to the bit head is carried out by the use of a soldering material of a particular composition containing 3 to 5% by weight of carbon, 0.5 to 3.0% by weight of silicon and the balance iron, the sum of the carbon content and the silicon content in the composition being at least 4% by weight relative to the total weight of the composition. Each of the tips which are to be soldered to the bit head by the use of the particular soldering material is made of either stellite or a super hard alloy.

Abstract: A voltage-dependent resistor comprising a sintered body consisting essentially of ZnO, as a main constituent, and, as additives, bismuth oxide (Bi.sub.2 O.sub.3), cobalt oxide (CoO) and/or manganese oxide (MnO) and/or aluminum oxide (Al.sub.2 O.sub.3) and gallium oxide (Ga.sub.2 O.sub.3) and/or indium oxide (In.sub.2 O.sub.3) with electrodes applied to the opposite surfaces of the sintered body. This voltage-dependent resistor has a low C-value, a high n-value, high power dissipation for surge energy and a high stability to a high D.C. load. Other additives such as titanium oxide (TiO.sub.2), chromium oxide (Cr.sub.2 O.sub.3) and nickel oxide (NiO) improve the voltage dependent property of the sintered body.