Abstract: A joint structure is a joint structure between a first member having a pillared end part made of a fiber-reinforced plastic and a second member different from the first member. The end part of the first member is reversely tapered in an axial direction, while a joining member is disposed along a reversely tapered form of the end part. The second member is provided in contact with an end face of the first member and connected to the joining member. A plurality of fibers substantially extending in the axial direction of the end part of the first member are provided within the end part and disposed to form a larger angle with the axial direction of the end part of the first member as they are disposed to be closer to a surface constituting the reversely tapered form in a radial direction of the end part.

Abstract: A joint structure is a joint structure between a first member having a pillared end part made of a fiber-reinforced plastic and a second member different from the first member. The end part of the first member is reversely tapered in an axial direction, while a joining member is disposed along a reversely tapered form of the end part. The second member is provided in contact with an end face of the first member and connected to the joining member. A plurality of fibers substantially extending in the axial direction of the end part of the first member are provided within the end part and disposed to form a larger angle with the axial direction of the end part of the first member as they are disposed to be closer to a surface constituting the reversely tapered form in a radial direction of the end part.

Abstract: The pressure vessel includes a tubular portion and a cover portion made of fiber reinforced plastics. The outer peripheral surface of an end portion of the tubular portion has a reverse-tapered shape of which the diameter is increased toward an end face. The cover portion includes a wedge-shaped member installed along the reverse-tapered shape of the outer periphery surface of the end portion of the tubular portion, an outer ring for covering the wedge-shaped member from the outside, an inner ring installed to cover an opening of the tubular portion and the wedge-shaped member and connected to the outer ring, and a sample cap connected to the inner ring.

Abstract: Vibrating wire viscometers are disclosed. An example vibrating wire viscometer includes first and second electrically conductive tubes, where the first tube is at least partially inserted into the second tube, and where the first and second tubes are coupled via an electrically insulating bonding agent. The example viscometer further includes first and second electrically conductive pins inserted into respective ones of the first and second tubes, and an electrically conductive wire fastened to the first and second pins to vibrate in a downhole fluid to determine a viscosity of the downhole fluid.

Abstract: Vibrating wire viscometers are disclosed. An example vibrating wire viscometer includes first and second electrically conductive tubes, where the first tube is at least partially inserted into the second tube, and where the first and second tubes are coupled via an electrically insulating bonding agent. The example viscometer further includes first and second electrically conductive pins inserted into respective ones of the first and second tubes, and an electrically conductive wire fastened to the first and second pins to vibrate in a downhole fluid to determine a viscosity of the downhole fluid.

Abstract: A sleeve for an acoustic logging tool has a structure with a window section having fewer bars than a conventional sleeve separated by a slotted region with thin circumferential slots which are stress-relieved at the ends (“dumb-bell” shaped). Steel receiver mounts are provided for hydrophone pressure sensors and this, together with the axially oriented hydrophones makes the tool less susceptible to interfering vibration.

Abstract: A sleeve for an acoustic logging tool has a structure with a window section having fewer bars than a conventional sleeve separated by a slotted region with thin circumferential slots which are stress-relieved at the ends (“dumb-bell” shaped). Steel receiver mounts are provided for hydrophone pressure sensors and this, together with the axially oriented hydrophones makes the tool less susceptible to interfering vibration.

Abstract: A sleeve for an acoustic logging tool having a structure with a window section having fewer bars than a conventional sleeve separated by a slotted region with thin circumferential slots which are stress-relieved at the ends (“dumb-bell” shaped). Steel receiver mounts are provided for hydrophone pressure sensors and this, together with the axially oriented hydrophones, makes the tool less susceptible to interfering vibration.

Abstract: An image intensifier tube and a solid-state image pickup device are combined to form a unified image pickup device. A thin fiber plate with thickness of 0.5-1.5 mm is interposed between a phosphor layer of the image intensifier tube and a photosensitive layer of the solid-state image pickup device. A microchannel plate may be incorporated to multiply photoelectrons emitted from a photocathode.

Abstract: An image intensifier tube and a solid-state image pickup device are combined to form a unified image pickup device. A thin transparent glass layer polished to a thickness of 50 microns or less is interposed between a phosphor layer of the image intensifier tube and a photosensitive layer of the solid-state image pickup device. A microchannel plate may be incorporated to multiply photoelectrons emitted from a photocathode.

Abstract: Process for indurating dried pellets in a rotary kiln, characterized by charging the dried pellets and coke in the range of from about 2% by weight to about 20% by weight on the weight of the pellets into the rotary kiln, the coke having a size of from about 5 millimeters to about 30 millimeters, drum index (DI.sub.5.sup.80) of more than 70, reactivity index (AG) of less than 50 and tumbler index (TI.sub.50.sup.400) of more than 50 measured on the basis of Japanese Industrial Standard K2151, and heating the pellets in the kiln is disclosed.