Grain hardness

Filter Beds. The sprinkling filter beds of sewage plants are composed of closely screened mineral aggregate of 38—64 mm or 51—76 mm that meet a severe soundness test. Much of this requirement is suppHed by dense, fine-grained, hard limestone and dolomite. 

Erebs, m. cancer crayfish grain, hard particle (in clay, etc.) knot (in ore, etc.) wart canker crab crustacean. 

Hardness of various brittle minerals, rocks and materials determined with the Mackensen blower with the use of various materials as abrasive grain. Hardness values for quartz, topaz and corundum have been taken as 7, 8 and 9 respectively on the Mohs scale... 

ARGILLITE. A dense, fine-grained, hard, sedimentary rock of various colors (usually while, gray or red). Composed of luniule grains of both day and quartz. Certain types of argillites are easily confused with certain types of fine-grained acid lava flows, such as felsites, unless studied microscopically. 

Salt Dosage, lb/ft3 Theoretical Capacity (grains) Hardness Leakage (ppm) ... 

Barron, C., Parker, M.L, Mills, E.N.C. and Rouau, X. (2005) FTIR imaging of wheat endosperm cell walls in situ reveals compositional and architectural heterogeneity related to grain hardness. Planta, 220, 557-77. 

What is the physical mechanism involved in variations of grain hardness ... 

It is interesting to trace the history of research on the origin of grain hardness because this illustrates how science works to increase... 

Figure 4.3 Schematic representation of the hypothesis proposed to explain the role of the 15,000-MW protein controlling grain hardness. (Reproduced with permission from Greenwell, R, and J. D. Schofield. 1986. FMBRA Bulletin 4 139-150.)...

The molecular genetic picture that has emerged to describe grain hardness can be summarized as follows. Endosperm softness is the dominantly inherited trait (i.e., the soft phenotype is the wild type). When both puroindoline a and puroindoline b are expressed, they work together to impart softness to the endosperm. When both are absent (as in durums), the endosperm is very hard. When only one is present, an intermediate degree of hardness is found. Another way in which an intermediate degree of hardness is obtained is when one of the puroindolines is present and the other has been altered as a result of mutation. 

Table 4.1 Puroindoline a and b Grain Hardness Alleles, Kernel Phenotype, and Molecular Changes in Expressed Proteins Resulting from Mutations...

The chemical basis of grain hardness and softness. In Wheat end-... 

Morris, C. F. 2002. Puroindolines The molecular genetic basis of wheat grain hardness. Plant Molecular Biology 48 633-647. 

Some traits associated with aspects of quality are dependent on only one or a few genes. For example, as we have seen in Chapter 4, grain hardness is controlled by a major gene on the short arm of chromosome 5D. The difference between red wheat and white wheat is caused by three genes that... 

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