摘要:
The present invention relates to a process for producing a composite having a reduced electrical resistance which comprises providing a mixture comprising a fluid material and carbon nanotubes (CNTs) having a predeterminable size distribution, and subjecting the mixture to a minimum stress in a dispersing machine, wherein the minimum stress is determined empirically as a function of the predetermined size distribution.
摘要:
An extruder with a housing comprising parallel, partially inter-engaging bores and screws disposed therein is used when applying a method of feeding powdery bulk materials into such an extruder. A solid transport of powdery bulk material takes place in an inlet zone disposed downstream of a feed opening wherein said inlet zone is partially filled. The inlet zone is provided with at least one gas-permeable wall portion wherein a layer of bulk material is created on said wall portion, thereby preventing bulk material from passing through.
摘要:
An extruder with a housing comprising parallel, partially inter-engaging bores and screws disposed therein is used when applying a method of feeding powdery bulk materials into such an extruder. A solid transport of powdery bulk material takes place in an inlet zone disposed downstream of a feed opening wherein said inlet zone is partially filled. The inlet zone is provided with at least one gas-permeable wall portion wherein a layer of bulk material is created on said wall portion, thereby preventing bulk material from passing through, The gas-permeable wall portion is connected to a vacuum source and to a pressure gas source. Furthermore, the gas-permeable wall portion has an inner wall which is set back with respect to the wall of the bores, thereby forming a gap with a partially annular cross section wherein a layer of the bulk material is formed in the gap.
摘要:
A gear pump comprises a casing and gear rotors disposed therein. The gear rotors are lodged in bearing sections of plain bearings that are lubricated by the pumping medium. They have at least one cooling duct which is embodied such that cooling varies along the circumference and/or in the longitudinal direction and/or in the radial direction of the plain bearing.
摘要:
In a method of carrying out continuous preparation processes on tightly meshing extruders rotating in the same sense such as twin-screw and multi-shaft screw-type extruders, the extruder is operated at a screw speed of rotation of at least 800 rpm, accompanied with a simultaneous increase of the so-called "torque density" (M.sub.d /a.sup.3) of at least 11 Nm/cm.sup.3 and a volumetric ratio (Da/Di) of at least 1.5.