Powder of the

The economics of recycling PET are more favorable than recycling HDPE. To iacrease the recycling of HDPE, the separation of bottles made of these two plastics could be omitted and a mixture processed. Coarse, light-colored powders of the two polymers have been prepared by an experimental soHd state shear extmsion pulverization process (55). The powder has been successfully injection molded without pelletization. 

Diketene is a flammable Hquid with a flash point of 33°C and an autoignition temperature of 275°C. It decomposes rapidly above 98°C with slow decomposition occurring even at RT. The vapors are denser than air (relative density 2.9, air air = 1). The explosive limits in air are 2—11.7 vol % (135). In case of fire, water mist, light and stabilized foam, as well as powder of the potassium or ammonium sulfate-type should be used. Do not use basic extinguisher powders and do not add water to a closed container. 

For the 2223 compound of the Tl-Ba-Ca-Cu-0 compound the loss of thallium is reduced by surrounding a pre-fired, and thallium-deficient, sample with powder of the compound and refiring. These substances also show a temperature-oxygen partial pressure stability relationship, similar to the classical 123 compound, but the details have not yet been elucidated. 

In most cases of interest, shock-induced chemical reactions in solids are studied in mixtures of powders of the potential reactants. In the earlier description of conceptual models it was emphasized that the pores provide space in which the potential reactants can be more intimately mixed in order... 

Principles The process consists of tumbling the metal to be coated with a powder of the coating metal. It is considered that a form of welding is involved, but the type of conditions conducive to successful deposition indicates that the deposit adheres by mechanical keying (A/, must therefore be relatively soft) and adhesive forces. Thus pretreatments such as abrading or pickling enhance the keying effect, and the use of a soft metal... 

Purification of Pholas luciferase (Michelson, 1978). Acetone powder of the light organs is extracted with 10 mM Tris-HCl buffer, pH 7.5, and the luciferase extracted is chromatographed on a column of DEAE Sephadex A-50 (elution by NaCl gradient from 0.1 M to 0.6 M). Two peaks of proteins are eluted, first luciferase, followed by a stable complex of luciferase and inactivated pholasin. The fractions of each peak are combined, and centrifuged in 40% cesium chloride... 

Davenport et al. (1952) were unsuccessful in their attempts to restore the luminescence of the filtered aqueous extract of Luminodesmus. Hastings and Davenport (1957) saw a weak luminescence in their filtered aqueous extracts made from the acetone powder of the millipedes. They found that the luminescence is dependent on pH, with an optimum at about pH 8.9, and that the light intensity could be increased by 10-30% by adding ATP. Hastings and Davenport also measured the luminescence spectrum of live animals, finding an emission peak at 495 nm. 

Owing to the high sintering temperatures employed, losses of material (by volatilization of boron or boride) and grain growth are observed. In order to limit these losses, the part to be sintered can be embedded in a powder of the same boride. Sintering of pure refractory borides requires > 0.7T, (Tj = absolute melting temper-... 

The reduction diffusion process has also been used for the production of powders of the magnetic neodymium-iron-boron alloy (Nd15Fe77B8). The reaction involves use of a powder mix of neodymium oxide, iron, ferroboron and calcium. The reaction is conducted by heating the powder charge mixture at 1200 °C for 4 h under vacuum. Neodymium-iron-boron alloys are much more prone to oxidation than samarium-cobalt alloys and a proprietary leaching procedure is used for the separation of the alloy and calcium oxide. 

One of the most widely used spray-drying techniques for coffee extract involves spraying percolated coffee extract at 40°F into the top of a baffled tower of hot air at 480°F initially. The cooler wet air is removed toward the bottom of the tower and finally a powder of the coffee extract solids leaves the tower at about 90°F. These solids are in the form of hollow beads and contain 3% moisture. 

Zuckerman et al. have extensively utilized this method in heterocyclic tin(II) chemistry 100). In some cases, this synthesis may also be performed with tin(II) chloride, the starting hydrochloride being coordinated by the addition of an amine 120). Free 171) and metal-bound tin(II) chloride 172) have been treated analogously with trimethyltin hydroxide to yield amorphous powders of the composition Sn(OH)2 and (CO)5MSn(OH)2 (M = Cr, W) and ClSnMe3. Unfortunately, no direct information on the structure of these compounds is available. 

Expensive semiconductor wafers are not required powders of the semiconductor suffice. This is convenient because various materials which are not available as electrodes can be used. 

For manufacturing of negative electrodes, suspensions containing 45wt% powder of the carbon material being examined, 5wt% PVDF, and 50wt% of the solvent. Copper foil with thickness of 0,02 mm was applied as substrate. 

The feasibility of carbon-supported nickel-based catalysts as the alternative to the platinum catalyst is studied in this chapter. Carbon-supported nickel (Ni/C, 10 wt-metal% [12]), ruthenium (Ru/C, 10 wt-metal% [12]), and nickel-ruthenium composite (Ni-Ru/C, 10 wt-metal%, mixed molar ratio of Ni/Ru 0.25,1,4, 8, and 16 [12]) catalysts were prepared similarly by the impregnation method. Granular powders of the activated carbon without the base pretreatment were stirred with the NiCl2, RuC13, and NiCl2-RuCl3 aqueous solutions at room temperature for 24 h, respectively. Reduction and washing were carried out in the same way as done for the Pt/C catalyst. Finally, these nickel-based catalysts were evacuated at 70°C for 10 h. 

Based on these data, particle-liquid Reynolds numbers were calculated to range from Re = 25 (50 rpm) to Re = 90 (150 rpm) for coarse grade particles with a median diameter of 236 pm. In contrast, Reynolds numbers for a batch of micronized powder of the same chemical entity with a median diameter of 3 pm were calculated to be significantly lower (Re < 1), indicating less sensitivity towards convective hydrodynamics [(10), Chapter 12.3.8]. Based on the aforementioned considerations for spheres, bulk Reynolds numbers of about Re > 50 appear to be sufficient to produce the laminar-turbulent transition around a rough drug particle of coarse grade dimensions. 

Extended homogeneity ranges of intermetallic phases have been studied by Singh et al. (2003) in the Mg-Al system. Powders of the two metals (325 mesh size) were mixed and the mechanical alloying performed using a hardened steel vial and... 

Powder metallurgical methods These include reaction of the elements and car-bothermal reduction methods. Fine powders of the metal (Hf, V, Nb, Mo, W, etc.) and carbon (graphite, lampblack) may be mixed, possibly in wet conditions with an organic solvent to be removed later, then pressed and compacted into pellets or bricks to be heated at high temperature (1800-2000°C). To perform the carbother-mal reduction, mixtures of carbon with an oxide (of Ti, V, Cr, etc.) are compacted and heated. An additional heat treatment in a high vacuum may be useful to remove O, N, etc. below a low level. 

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