Inorganic materials, transport

Stallard, R. F., Koehnken, L., and Johnsson, M. J. (1991). Weathering processes and the composition of inorganic material transported through the Orinoco River system, Venezuela and Colombia. Geoderma 51,133-165. 

The profile of a peat deposit commonly shows very clearly the successions of plant life that occurred during the period of perhaps 2,000-10,000 years required for it to form. The first organic additions, found at the bottom of the deposit, are largely material of foreign origin, such as pollen, spores, and other plant materials. Mixed with these transported materials are the remains of plants, especially algae and other plankton, and inorganic materials transported by winds or water. 

Bone is a porous tissue composite material containing a fluid phase, a calcified bone mineral, hydroxyapatite (HA), and organic components (mainly, collagen type). The variety of cellular and noncellular components consist of approximately 69% organic and 22% inorganic material and 9% water. The principal constiments of bone tissue are calcium (Ca ), phosphate (PO ), and hydroxyl (OH ) ions and calcium carbonate. There are smaller quantities of sodium, magnesium, and fluoride. The major compound, HA, has the formula Caio(P04)g(OH)2 in its unit cell. The porosity of bone includes membrane-lined capillary blood vessels, which function to transport nutrients and ions in bone, canaliculi, and the lacunae occupied in vivo by bone cells (osteoblasts), and the micropores present in the matrix. 

The main focus of the following considerations is on catalysis using inorganic materials. Similar considerations come into play for catalysis with molecular compounds as catalytic components of course, issues related to diffusion in porous systems are not applicable there as molecular catalysts, unless bound or attached to a solid material or contained in a polymeric entity, lack a porous system which could restrict mass transport to the active center. It is evident that the basic considerations for mass transport-related phenomena are also valid for liquid and liquid-gas-phase catalysis with inorganic materials. 

Quantum dots are the engineered counterparts to inorganic materials such as groups IV, III-V and II-VI semiconductors. These structures are prepared by complex techniques such as molecular beam epitaxy (MBE), lithography or self-assembly, much more complex than the conventional chemical synthesis. Quantum dots are usually termed artificial atoms (OD) with dimensions larger than 20-30 nm, limited by the preparation techniques. Quantum confinement, single electron transport. Coulomb blockade and related quantum effects are revealed with these OD structures (Smith, 1996). 2D arrays of such OD artificial atoms can be achieved leading to artificial periodic structures. 

Drickamer contributed much to the knowledge of diffusion in gases and liquids. As an example, recent studies of the effect of pressure upon material transport in several inorganic systems have been made available... 

Soil Layered (having horizons) and usually fine-grained and often unconsolidated (loose) organic and inorganic materials that form from the weathering of rocks and biological activity. At least some of the materials in soils form in-place rather than being transported from distant locations by wind, ice, or liquid water (compare with sediment, A horizon, B horizon, and C horizon). 

Streams form a cmcial link in larger scale biogeochemical cycles, both through down-stream transport of terrigenous materials and gas exchange between samrated soils of stream corridors and the atmosphere. Surface runoff represents the primary pathway by which organic and inorganic materials are transferred from continents to... 

Several inorganic materials, especially the ceramic type, exhibit selective transport of species in the form of gas, ions or atoms through them and can be utilized as sensors. Sensors are those devices that convert nonelectrical signals into electrical ones. Although the applications are not directly related to separation processes, their underlying principles are the same as those governing the membranes used in traditional separation applications. Their uses as gas or chemical sensors deserve brief discussions here. 

The sources of particulate phosphorus to the seabed include detrital inorganic and organic material transported by rivers to the ocean, biogenic material produced in the marine water column that sinks to the seabed, and atmospheric... 

Selective surface flow is, as Knudsen diffusion, associated with transport through microporous membranes, usually inorganic materials. The mechanism of surface diffusion is disputed and several different approaches have been proposed in the literature. 

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