A thermoelectric conversion material expressed by a chemical formula X.sub.3T.sub.3-yT′.sub.ySb.sub.4 (0.025≦y≦0.5), wherein the X includes one or more elements selected from Zr and Hf, the T includes one or more elements selected from Ni, Pd, and Pt, while including at least Ni, and the T′ includes one or more elements selected from Co, Rh, and Ir.

Provided are a sliding member and a sliding bearing which can improve the fatigue resistance. A sliding member having a base layer and a coating layer laminated on the base layer, in which the coating layer contains Bi or Sn as a first metal element, a second metal element which is harder than the first metal element and forms an intermetallic compound with the first metal element, C, and unavoidable impurities.

Provided are a sliding member and a sliding bearing which can improve the fatigue resistance. A sliding member having a base layer and a coating layer laminated on the base layer, in which the coating layer contains Bi or Sn as a first metal element, a second metal element which is harder than the first metal element and forms an intermetallic compound with the first metal element, C, and unavoidable impurities.

The present invention provides a thermally deformable annular packer with pressure relief means for use in oil and gas wells. The annular packer is formed from a stack of component parts, said parts comprising one or more eutectic alloy based ring sections sandwiched between two end sections. At least one of the annular packer component parts has one or more enclosed voids that are configured to become exposed when the packer is subjected to a predetermined pressure or temperature. The exposure of the enclosed voids serves to increase the effective volume within the sealed region formed by the annular packer in the annulus between two coaxial well casing/tubing. The increase in the effective volume serves to reduce the pressure within the sealed region thus preventing a build-up of pressure that might otherwise have damaged the well casing/tubing.

Some implementations of the disclosure relate to a lead-free solder paste with mixed solder powders that is particularly suitable for high temperature soldering applications involving multiple board-level reflow operations. In one implementation, the solder paste consists of 10 wt % to 90 wt % of a first solder alloy powder, the first solder alloy powder consisting of an SnSbCuAg solder alloy that has a wt % ratio of Sn:Sb of 0.75 to 1.1; 10 wt % to 90 wt % of a second solder alloy powder, the second solder alloy powder consisting of an Sn solder alloy including at least 80 wt % of Sn; and a remainder of flux.

A wellbore is plugged using a bismuth alloy. The wellbore is arranged so that a liquid bismuth alloy sets with an excess pressure of the plug relative to the borehole fluid pressure along a desired seal height distance.

A wellbore is plugged using a bismuth alloy. The wellbore is arranged so that a liquid bismuth alloy sets with an excess pressure of the plug relative to the borehole fluid pressure along a desired seal height distance.

The present disclosure provides a thermoelectric conversion material having a composition represented by a chemical formula of Ba.sub.1-a-b-cSr.sub.bCa.sub.cK.sub.aMg.sub.2Bi.sub.2-dSb.sub.d. In the chemical formula, the following relationships are satisfied: 0.002≤a≤0.1, 0≤b, 0≤c, a+b+c≤1, and 0≤d≤2. In addition, the thermoelectric conversion material has a La.sub.2O.sub.3-type crystal structure.

Solder pastes comprise a high temperature solder powder, a low temperature solder powder and flux. The melting temperature of the low temperature solder powder is lower than that of the high temperature solder powder. The high temperature solder powder and the low temperature solder powder are both capable of wetting upon heating.

Solder pastes comprise a high temperature solder powder, a low temperature solder powder and flux. The melting temperature of the low temperature solder powder is lower than that of the high temperature solder powder. The high temperature solder powder and the low temperature solder powder are both capable of wetting upon heating.