Powder homogeneous powders

Rhovanil Extra Pure is the standard mesh, multipurpose quaUty of food-grade extra pure vanillin. Its broad particle-size distribution shows a versatile granulometry, compatible with a wide range of granulometric profiles from any other ingredients, and allows a homogeneous powder mixabiUty, even at low content in a given blend. 

Another popular form of data pre-processing with near-infrared data is the application of the Multiplicative Scatter Correction (MSC, [28]). It is well known that particle size distribution of non-homogeneous powders has an overall effect on the spectrum, raising all intensities as the average particle size increases. Individual spectra x, are approximated by a general offset plus a multiple of a reference spectrum, z. 

Homogenize 50 g of a prepared sample with 100 mL of methanol in a macerator for 3 min. In the case of green tea (powder), homogenize 10 g of a prepared sample with 100 mL of acetone-water (7 3, v/v) and shake for 30 min with a mechanical shaker. 

In the first group of methods, small particles are produced from larger ones by mechanical treatment. Naturally, it is an uneasy task to obtain homogeneous powders with uniform size distribution by means of comminution, therefore, in modem applications, chemical methods prevail. 

The preparation of AChE-biotest includes the following stages, (i). the preparation of homogenate from tissue with high cholinesterase activity (electrical organ acetone powder). Homogenate are preparated in phosphate... 

Dry powders must be able to flow readily in order to leave the capsule or powder reservoir, but must also generate a fine aerosol enabling the patient to inhale a proper dose. These two requirements are often difficult to achieve simultaneously. Fine powders tend to be eohesive and have poor flow properties. Blending with a carrier phase, pelletization, and other approaches have been used to overcome these limitations. The featmes of blends and homogeneous powders are compared in Table 4 from a DPI device perspective ... 

Extraction of samples. Plant tissues were lyophilized after harvest and ground to a homogeneous powder in a Wiley mill (no. 20 mesh). Samples (0.500 g) of lyophilized whole leaf were extracted in 125 mL roundbottom flasks by steeping in 25 mL of chloroform for 30 min. The extract was filtered and the filtrate set aside. The extraction flask and filtered solids were rinsed with an additional 15 mL of fresh chloroform. The filtrate from the rinse was then combined with the original filtrate and the resulting solution was evaporated to dryness with a rotary evaporator. The dry solids were redissolved in a mixture of 20.0 mL methanol and 5.0 mL acetone using sonication to assist in dissolving of all solid material. 

Cadmium pigments are sold as homogeneous powders and as preparations mixed with barium sulfate to give the required tinting strength. To reduce the risk of inhalation (see Section 3.2.8), they are supplied as low-dust powders and fine granules. 

Calcined MCM-41 was dehydrated at 120°C under 10 3 torr for three hours. Different amounts of the copper tellurolate cluster I were then mixed with dehydrated MCM-41. The mixture was mechanically stirred under nitrogen at atmospheric pressure until a yellow homogeneous powder was obtained. TGA, PXRD and IR studies were then carried out. 

Diazirine 43 (1.0 g, 4.99 mmol) was dissolved in pyridine (20 mL) and H20 (maximum amount that allows soln to stay homogenous). Powdered KMn04 (4 equiv) was added and the soln stirred at 50 °C. After 20 h, the mixture was diluted with H20 (150 mL), acidified with 0.5 M H2SQ4 to pH 2-3, and aq... 

X-ray fluorescence is a rapid and low-cost method that can be performed on solid samples. However, the depth of penetration of X-rays in most solid samples is relatively shallow. High-precision XRF on geological samples such as obsidian requires preparation of homogeneous, powdered samples pressed into pellet form. If some loss of precision and accuracy due to irregular size, shape, and thickness of samples is acceptable, obsidian specimens can be analyzed non-destructively. Samples smaller than 1 cm in diameter or with element concentrations less than 5 ppm are generally not suitable for XRF. XRF can determine about 10-15 elements in obsidian (K, Ti, Mn, Fe, Zn, Ga, Rb, Sr, Y, Zr, Nb, Pb, and Th). Fortunately, many of the measurable elements are the incompatible elements which provide discrimination between sources. 

The study of different methods of granulation of aminoplasts shows that the given process involves compaction of an homogeneous powdered product with subsequent sizing and forming of the compact product. 

Crust and crumb are then taken in the proper proportions to give a sample of at least ioo grams, this being dried at 100-105° for 2 -3 hours and then reduced to a homogeneous powder m a mortar. The powdered sample is kept in a sulphuric acid desiccator and when the various portions required for the different determinations are to be weighed out (the weighings are to be made consecutively and rapidly, in order to avoid absorption of moisture) it is put in the oven again for 2 hours at 100-105°. The samples of crust and crumb separately are prepared in the same way. 

A mixture of acidic alumina (9.3 g) and ammonium acetate (4.4 g) was ground in a mortar until a homogeneous powder was formed. A solution of 0.5 mmol of 1,2-dicarbonyl compound and 0.5 mmol of aldehyde in 2 mL of diethyl ether or... 

When manufacturing a tablet formulation by direct compression, the particle size and size distribution of excipients have a significant impact on blending homogeneity, powder segregation, and flowability. This can result in unacceptable content uniformity and high tablet weight variation. In such situations, control of excipients can be critical to product quality. 

---