Sharp angles

Surfa.ce, Any reaction between two powder particles starts on the surface. The amount of surface area compared to the volume of the particle is, therefore, an important factor in powder technology. The particle—surface configuration, whether it is smooth or contains sharp angles, is another. The particle surface area depends strongly on the method of production, as shown in Table 1. The method of production usually determines the particle shape. 

The presence of notches or sharp angles or of a few holes, voids, particle inclusions or small inserts tends to concentrate the stress. Different polymers vary in their notch sensitivity and this is presumably a reflection of how close they are to their tough-brittle transitions. The aim of the designer and processor must be to reduce such stress concentration to a minimum. 

When laying out a firing system using primacord, avoid sharp angles or bends in the lines. The shock wave in the cord as it detonates will turn... 

Ducts are used to transport the exhaust air and its contaminants to the collection area. An important feature of duct design is reduction of resistance to air flow from friction within the wall, aggravated by unnecessary curves and bends (particularly right-angled bends), as well as junctions with other ducts at sharp angles, collections of dust, and changes in duct diameter. 

Film a pre-decorated film is laid out onto the surface of the part to be decorated. There are a myriad of insert shapes, which are often patented. The insert shape must favour its mechanical anchorage faces, flat sides, grooves, milling, barbs, perforations... that allow the flowing of the thermoplastic. However, sharp angles initiate cracks and the geometric anchors should be located as far as possible from the surface. 

In most standard tests the maximum force measured during the test is recorded and no distinction is made between initiation and propagation. Also, most standard tests start with an artificially introduced cut which can be thought of as the initiation. The discontinuity at which the stress concentration is produced is formed either by a cut, a sharp re-entry angle or both. Only in the case of a sharp angle without a cut will any measure of initiation force be possible. 

The angle between the two gripped legs of the test piece is nominally 180° (see Figure 18.2). The plies should separate at a sharp angle but this will depend on the thickness and stiffness of the plies. The standard suggests... 

It is preferable not to heat a beaker or Erlenmeyer flask with Fisher or Bunsen burners. The reason is discussed in detail in Sec. 1.1.10, which discuses the structural shapes of flasks. In essence, the problem is that the sharp angle of the side walls may not be able to disperse the thermal strains created by the expanding heated bottom. Round-bottom flasks, on the other hand, have no side walls and therefore do not have this problem. 

The victims had been herded into the ravine the heavy machine guns were fired downward at a sharp angle - not an easy task. 

For flow domains involving singularities such as sharp angles and those involving firee surfaces, the geometrical discontinuities are not explicitly taken into... 

Carbon fibers are flexible enough to permit implantation in a number of tissues, including the wall of the intestine [138]. However, sharp angles must be avoided, since the fibers will break and their small diameter makes them difficult to handle. Table 6 gives examples of conducting devices in medical applications. 

Thera are some simple things to remember regarding commercial time fuse, rirst It should be stored In a oool dry place. 7t should not be bent at sharp angles or subjected to rough treatment It Is best cut with a sharp knife, using stssdy pressure rather then e "sawing" motion The boles should be drilled with s sharp hand drill slowly. 

Zig-zagi flexuous with sharp angles, as the teeth of a saw. 

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