Weight reduction examples

The hexagonal-close-packed (hep) metals generally exhibit mechanical properties intermediate between those of the fee and bcc metals. For example Zn encounters a ductile-to-brittle transition whereas Zr and pure Ti do not. The latter and their alloys with a hep structure remain reasonably ductile at low temperatures and have been used for many applications where weight reduction and reduced heat leakage through the material have been important. However, small impurities of O, N, H, and C can have a detrimental effect on the low temperature ductihty properties of Ti and its alloys. 

Several arbitrary rules of thumb have been suggested to account for the reduction in efficiency when moisture particles are present. One is to multiply the efficiency by the mean vapor content, by weight. For example, if expansion is started in the superheated region and ends with 6% by weight of liquid, the mean vapor content is 97%. If the design efficiency is 78%, the adjusted value of efficiency is 0.78 (0.97) = 0.757 or 75.7%. Some designers prefer to assume a loss equal to twice the value used in the example. 

One factor in the reduction of healthcare expenditure is home medical care, which involves adaptations of the methods of care. These uses dictate particular requirements for sterility, safety, reliability, weight and facility of use. Plastics can bring solutions in the fields of single-use products, unbreakable equipment and weight reduction, for example, in the syringes, tubes and pumps for drug injections and apparatus for ambulatory dialysis. 

For many years syntactic foams have been used in construction, in sandwich structures, or as imitation wood or marble 22,57 180). Many types of these materials are applied in the boat-building industry 17 66). For example, recently PVDC microspheres with polyester binder were used to produce the decks of a 10 m sail-boat, with a weight reduction of 100 kg (from 250 to 150 kg)46). 

Most recently, Gallagher et al.21 measured the water uptake of Nafion membrane under subfreezing temperatures, which showed a significant reduction in the maximum water content corresponding to membrane full hydration. The Nafion membrane with 1,100 equivalent weight, for example, uptakes A 8 of water at -25°C when it equilibrates with vapor over ice because of the low vapor pressure of ice compared to supercooled liquid water. They also found the electro-osmotic drag coefficient to be 1 for Nafion membrane under sub freezing temperatures. 

Equation (30j is called the reduction spectrum of the tensor T n). Each irreducible tensor of rank n and weight J has 3" components labeled by n indices, and its 3" components form the basis of an irreducible representation of the three-dimensional rotation group of degree 27 -h 1. Elence, each irreducible tensor with weight J has U 4- 1 independent components. The superscript y distinguishes between different components of identical weight. For example, the reduction spectrum of the hyperpolarizability tensor f3 (rank three) is ... 

With few exceptions weight reduction of parts in mobile applications is good. However, the carbon-fiber example shows the situation can only be judged for the concrete case and application. 

The comparison of the housing geometry of active and passive sensors clearly shows the reduction of sensor dimension and weight reduction. The applied ASICs enable a large family of application-specific constructions because of their minimal packaging. Fig. 7.9.9 shows examples for further configurations. 

---