magnetite is a rock mineral and one of the main iron ores, with the chemical formula fe 3o 4 . it is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself.
hydrogeology, as stated above, is a branch of the earth sciences dealing with the flow of water through aquifers and other shallow porous media typically less than 450 m below the land surface . the very shallow flow of water in the subsurface the upper 3 m is pertinent to the fields of soil science, agriculture and civil engineering, as well as to hydrogeology.
a number of software products are available for calculating cut and fill. a simple approach involves defining different earthworks features in a software program and then adjusting elevations manually to calculate the optimal cut and fill. more sophisticated software is able to automatically balance cut and fill and take account of materials.
the kozeny–carman equation or carman–kozeny equation or kozeny equation is a relation used in the field of fluid dynamics to calculate the pressure drop of a fluid flowing through a packed bed of solids. it is named after josef kozeny and philip c. carman. the equation is only valid for laminar flow.the equation was derived by kozeny 1927 and carman 1937, 1956 from a starting point .
the manning formula is an empirical formula estimating the average velocity of a liquid flowing in a conduit that does not completely enclose the liquid, i.e., open channel flow.however, this equation is also used for calculation of flow variables in case of flow in partially full conduits, as they also possess a free surface like that of open channel flow.
a sieve analysis can be performed on any type of non-organic or organic granular materials including sands, crushed rock, clays, granite, feldspars, coal, soil, a wide range of manufactured powders, grain and seeds, down to a minimum size depending on the exact method. being such a simple technique of particle sizing, it is probably the most common.
equation for calculation. if the water table is at depth d w in fine-grained soils, then the pore pressure at the ground surface is: = −, where: p g is the unsaturated pore water pressure pa at ground level, g w is the unit weight of water kn/m 3 , = /