Size-weight ratio

In practice we have to limit the quantity of material, as most modern methods require only minimal amounts of samples. Usually we reduce the particle size by mixing. Frequently, as a measure for the introduction of the additional variation by the subsampling procedure the size-weight ratio is introduced. This is defined as... 

Size, weight, capacity, and power density are the primary selection considerations for batteries in externally powered prosthetic design applications. The most popular types of rechargeable batteries in use in prosthetics today are nickel-cadmium (NiCd), nickel-metal-hydride (NiMH), and lithium-ion (Li-ion). Li-ion is fast becoming the chemistry of choice because of its high capacity-to-size (weight) ratio and low self-discharge characteristic. 

Similar structure vs jump-like creep correlations were revealed for neat epoxy network [310,311] and for the composite based thereon and filled with diabase particles of 5-10 pm size (weight ratio of both components was 1 1) [310]. Electton... 

Fig. 80 Variation of creep rate within the narrow range of strains for the epoxy composite with diabase particles of 5-lOp.m in size (weight ratio of 1 1). T = 20°C, compressive stress c = 60MPa. The values of large period L of creep rate variation are indicated [310]...

A more comprehensive purification procedure uses a sequence of steps as follows filtration at 200°C through a stainless steel powder compact filter of 10-jum pore size reduces the oxygen content and removes any solid impurities. Gettering with Zr foil for 46 h at 760°C reduces the oxygen concentration to 200 ppm. The weight ratio of K to Zr is 13 1 with a surface area to volume ratio of Zr to K 4 1. A second gettering with zirconium foil for 72 h at 800°C reduces the oxygen content 50 ppm. 

Raw materials were ground to a particle size less than 630 pm. Physical mixtures of solid KOH and a given precursor at 2 1, 3 1, 4 1 and 5 1 weight ratios were activated in the temperature range of 600-900°C for 1-5 h under argon flow of 15 dm3/h. The treatments were carried out in a horizontal furnace using a nickel boat placed in a 36 mm diameter quartz tube. The heating rate was 10°C/min. The resultant materials were washed with 10% solution of HC1 and distilled water and next were dried at 110°C for 6 h. 

Commonly, roughness can be tailored by using additives. These are mainly based on combinations of inert, inorganic particles of different sizes and the weight ratio of large to small particle sizes. These particles should be well dispersed in the base film to prevent abrasion, which is influenced by the particle shape and the kind of embedding in the polymer matrix. The affinity of these particles to the solid polymer seems to be based on adhesion of the melt to the solids and to cohesive forces in the solid state. This phenomenon, however, has not yet been explored in sufficient detail. 

Fig. 2.39 The effect of baU-to-powder weight ratio on the particle size of MgHj synthesized by reactive ball milling for 30 h in the magneto-mill Uni-BaU-MUl 5 [63]...

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