Pigments irregular shape

ABN. PIGMENT. OPTIC NERVES FAILURE OF THE CHOROID CRYSTALLINE LENS OUT ABN.PIGMENTAT10N gg INCOMP. SEPARATION CYCLOPIA IRREGULAR SHAPE MALPOSITIONED MICROPHTALMIA ABSENT... 

E 16, 32, 64, 71, 78 mg/L Gut miscoilin0 from 32 mg/L. Axis malformation and edema from 64 mg/L Eye malformation (failure of the choroid, irregular shape with abnormal pigmentation) from 32 to 78 mg/L. Heart malformation Lfnderdeveloped (1 larva/concentration at 71, 78 mg/L) External malformation Domed head with hydrocephaly (4 fetuses from 2 litters at 1,000 mkd, two with microglossia). Domed head with hydrocephaly in the preliminary study (4 fetuses from 2 litters at 1,000 mkd, one with microglossia). Visceral malformation 1 Microcardia... 

Miscoiling of gut (15), eyes with irregular shape (3), microphthalmia (2), abnormally pigmented optic nerves failure of the choroid (1), edema C (4), edema AC (5), edema ACO (1), incomplete development of Mouth (2), heart malpositioned (1), heart underdeveloped (1), nares malpositioned (1)... 

The shape of the pigment particle depends very much on the manufacturing conditions. Basically we distinguish between the traditional cornflake-type (irregular shaped) and the so-called silver dollar-type (lenticular, round-shaped, smooth surface). The thickness of these pigments varies from 0.1 to 1 pm (Figure 5.30). 

Lentigo maHgna is a flat, multicolored, pigmented lesion with an irregular shape that may be precancerous. It has a slow radial growth phase and its diameter can vary from a... 

We now consider the interface between carrier and toner, as these components interact in a dynamic development system. As we have noted, toner is commonly fabricated by "jet impacting" a brittle pigmented thermoplastic to form irregularly shaped particles of about 12/u m cross-section--particles whose surface comprises resin and carbon black (2, J 3, 58). The carrier cores are magnetic (ferrite or steel), typically about 250/4 m in size and therefore relatively massive. They are generally coated with a dielectric oxide or resin, which participates in the tribo-electrification process (2, it , 59). ... 

Particles may be nearly spherical, cubic, nodular (a rounded irregular shape), acicular (needle- or rod-like) or lamellar (plate-like). Since particle shape affects pigment packing, it therefore affects hiding power. Rod-shaped particles can reinforce paint films, like iron bars in concrete, or they may tend to poke through the surface reducing gloss. 

Fig. 5.2 Cross sectional views of representative fibers show the fiber shapes and dense pigment particles. The fibers are (A) round polyamide, (B) irregularly shaped polyacrylonitrile, (C) trilobal shaped Orion, and (D) dogbone shaped Orion fiber sections.

Acryhc and modacryhc fibers are sold mainly as staple and tow products with small amounts of continuous filament fiber sold in Europe and Japan. Staple lengths may vary from 25 to 150 mm, depending on the end use. Eiber deniers may vary from 1.3 to 17 dtex (1.2 to 15 den) 3.2 dtex (3.0 den) is the standard form. The appearance of acryhcs under microscopical examination may differ from that of modacryhcs in two respects. Eirst, the cross sections (Eig. 1) of acryhcs are generally round, bean-shaped, or dogbone-shaped. The modacryhcs, on the other hand, vary from irregularly round to ribbon-like. The modacryhcs may also contain pigment-like particles of antimony oxide to enhance their flame-retardant properties. 

As seen today, Chamber IV is very irregular in shape. It has two dead comers, is closed on three sides, and therefore very difficult to ventilate. This one, exactly identical to the hair-cutting room in hut 42, shows blue pigmentation on the ceiling and plaster of the northern wall. This blue pigmentation is also found in the plaster on the southern wall, but is on the outside of the wall of Chamber IV. An even more intense bluish pigmentation finally appears in the plaster of the eastern wall, in the vestibule. 

The term filler is very broad and encompasses a very wide range of materials. In this book, we arbitrarily define as fillers a variety of solid particulate materials (inorganic, organic) that may be irregular, acicular, fibrous, or plate-like in shape and that are used in reasonably large volume loadings in plastics. Pigments and elastomeric matrices are normally not included in this definition. 

There are only a few colorants that meet the above described constraints these are essentially some inorganic compounds such as iron oxides [43] or cadmium sulfide. Most commercial pigments, and especially the commonly used metal dye "lakes", are of irregular particle shapes and polydisperse. Because these solids are mostly insoluble in any solvent and decompose on melting, it is not feasible to prepare them as uniform particles. 

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