Powder purity

Sodium erl -Butylate. Sodium / i -butoxide [865-48-5] (CH2)3CONa, mol wt 96.1, is a pale yellow, free-flowing, caustic, hygroscopic powder purity 95—99% bulk density 0.3—0.4 g/mL fairly soluble in alcohols, sparingly soluble in ether and hydrocarbons. 

Potassium Methylate. Potassium methoxide [865-33-8] KOCH, mol wt 70.13, is a fine, free-flowing, yellowish-white, caustic, hygroscopic powder purity 96.5—99% powder density after loose shaking, 0.75 g/mL apparent density (packing weight), 1.00 g/mL medium grain size, 0.05 —0.8 mm easily soluble in alcohols (33% in methanol at 20°C), insoluble in hydrocarbons. 

Water Atomization -100 Standard deviation 1.7-2.4 Fe, Cu, Cu alloys, Stainless steels. Tool steels, Ni alloys, Precious metals 104-106 400 15-60 Steel iron 0.5-5 Stainless steel Cu alloys High volume, Low cost Powder purity shapeXow EE... 

Water atomization is intrinsically a high volume, low cost process. Therefore, it is generally more cost-effective compared to other commercial atomization methods. However, powder purity,... 

Powder cocaine (cocaine hydrochloride) can be over 100 times more potent than coca leaves. By adding acids and purifying agents, 22 lbs (10 kg) of coca paste can be refined to 2.2 lbs (1 kg) of powder. This powder approaches 100% purity, but it is diluted with fillers before it is sold on the streets in the United States. Common fillers are cheaper drugs such as amphetamines or sugars such as lactose or inositol. Average street powder purity is 60%. The most common way to use powder is to snort it into the nose, but it can also be dissolved in water and injected into the veins. Powder cocaine cannot be smoked. Powder cocaine is addictive when snorted and highly addictive when injected. 

The sinterability of MgO powder depends on powder purity, particle size, precalcination stage and temperature.31 MgO of purity ranging from 98.5%... 

A soln of H-D-Trp-D-Asp(OtBu)-Pro-D-Val-Leu-OH (80) (4.00 g, 7.0 mmol) in DMF (20 mL) was added dropwise to a soln of HBTU (3 equiv) and DIPEA (6 equiv) in DMF (200 mL) at rt over a period of 30 min. The cyclization was complete after an additional 30 min, as monitored by HPLC. The soln was concentrated and the crude protected cyclic peptide was treated with 50% TFA in CH2CI2 for 30 min to yield the crude cyclopeptide 81 which was purified in 3xl.2g batches on a Vydac Cl 8 column (5.2 X 25.0 cm) by eluting with a linear gradient of A (0.1% TFA in H2O) and B (0.1% TFA in MeCN), from 70% A to 40% A over 129min (30.0mL-min" ). Fractions containing pure product were combined, concentrated and lyophilized yield 2.4g (36%) white powder (purity >98%, HPLC), which was converted quantitatively into its monosodium salt. 

Appearance White to off-white crystalline powder Purity 98—99%... 

The reason for this enhanced demand for powder purity originates in the fiict that remaining impurities after sintering greatly affect the woikability (grain boundary strength, reciystallization temperature, etc.) and properties of the final product. 

Hong, B. S., Kang, S.-J. L. and Brook, R. J., The effect of powder purity and sintering temperature on the micro structure of sintered AI2O3, unpublished work, 1988. 

The well-known nonequilibrium process of plasma chemical synthesis has found practical application for a large number of compounds and compositions. However, in recent years more attractive and well-developed processes of synthesis become gas phase condensation under quasi-equilibrium conditions of moderate heat and mass transfer. This process becomes preferable over latter plasma chemical synthesis due to its ability to control the thermal regime and more flexibility in regard to dispersion and purity of the synthesized product. Uniformity of particle size and chemical composition (powder purity) are essential for fabrication of nanocomposites or dense nanocrystalline materials with improved physical, chemical and mechanical properties. This is because the particle size distribution determines the stability of grains during consolidation of a polycrystal while the concentration of impurities affects properties of grain boundaries and entire material (Table 5.1). 

Powder Purity (wt%) Specific Surface Area (ni /g) Particle size (urn)... 

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