Abstract: In one general aspect, a microelectronics cooling device can include a microchannel heat exchanger within an enclosure that houses the device at a heat absorbing end and another heat exchanger which is optionally also a microchannel heat exchanger at a heat sink end outside the enclosure. One or more pipes flowably connect the two ends for transporting liquid working fluid to the heat absorber and vaporized working fluid to the heat sink. The heat pipes may also be used to transfer heat outside a room that contains the electronic devices.

Abstract: In one general aspect, a microchannel heat exchanger is disclosed. It includes a cover, a base, and thermally conductive sheets between the cover and the base that each define a series of side-by-side lanes aligned with a flow direction. The lanes each include aligned slots that define microchannel segments and are separated by cross ribs. The sheets are stacked between the base and cover so as to cause at least some of the ribs to be offset from each other and allow the microchannel segments in the same lane in adjacent sheets to communicate with each other along the flow direction to define a plurality of microchannels in the heat exchanger.

Abstract: A method for manufacturing 1,4-bis(4-phenoxybenzoyl)benzene, including: reacting terephthaloyl chloride with diphenyl ether in the presence of a Lewis acid, so as to obtain a product mixture including 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex, wherein the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex is, at least partly, in the form of a precipitate; carrying out a solid/liquid separation of the product mixture to obtain a cake comprising the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex precipitate; putting the cake in contact with a decomplexing solvent, wherein the decomplexing solvent is a protic solvent, so as to dissociate the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex into 1,4-bis(4-phenoxybenzoyl)benzene; and, recovering the 1,4-bis(4-phenoxybenzoyl)benzene. Also, a method for manufacturing a polyaryletherketone polymer starting from 1,4-bis(4-phenoxybenzoyl)benzene manufactured by the above method.

Abstract: In one general aspect, a converging split-flow microchannel evaporator is disclosed. It includes a conductive contact surface to mate to a surface to be cooled, with a core mounted in thermal connection with the conductive surface that defines at least one layer of microchannels. Within the core, one inlet restriction restricts the flow into each microchannel in a first group of the microchannels, and another restricts the flow into each microchannel in a second group. A centrally located fluid outlet receives the flows from opposite ends of the microchannels in the two groups. A check valve can be provided to help ensure ready startup without reverse flow.

Abstract: A method for manufacturing 1,4-bis(4-phenoxybenzoyl)benzene, including: reacting terephthaloyl chloride with diphenyl ether in the presence of a Lewis acid, so as to obtain a product mixture including 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex, wherein the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex is, at least partly, in the form of a precipitate; carrying out a solid/liquid separation of the product mixture to obtain a cake comprising the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex precipitate; putting the cake in contact with a decomplexing solvent, wherein the decomplexing solvent is a protic solvent, so as to dissociate the 1,4-bis(4-phenoxybenzoyl)benzene-Lewis acid complex into 1,4-bis(4-phenoxybenzoyl)benzene; and, recovering the 1,4-bis(4-phenoxybenzoyl)benzene. Also, a method for manufacturing a polyaryletherketone polymer starting from 1,4-bis(4-phenoxybenzoyl)benzene manufactured by the above method.

Abstract: In one general aspect, a microchannel heat exchanger is disclosed. It includes a cover, a base, and thermally conductive sheets between the cover and the base that each define a series of side-by-side lanes aligned with a flow direction. The lanes each include aligned slots that define microchannel segments and are separated by cross ribs. The sheets are stacked between the base and cover so as to cause at least some of the ribs to be offset from each other and allow the microchannel segments in the same lane in adjacent sheets to communicate with each other along the flow direction to define a plurality of microchannels in the heat exchanger.

Abstract: In one general aspect, a microelectronics cooling device can include a microchannel heat exchanger within an enclosure that houses the device at a heat absorbing end and another heat exchanger which is optionally also a microchannel heat exchanger at a heat sink end outside the enclosure. One or more pipes flowably connect the two ends for transporting liquid working fluid to the heat absorber and vaporized working fluid to the heat sink. The heat pipes may also be used to transfer heat outside a room that contains the electronic devices.