Deposits dense

In 1956, Ralph K. Her filed a patent application for a coating process that deposited dense shells of hydrated amorphous silica on cores of other sohd materials. On May 5, 1959, patent 2,888,366 was awarded to Her and his assignor, DuPont. 

W-BiV04 Ultrasonic spray deposition Densely packed nanoparticles 100 nm in size 2.65 Monochromatic light 0.5 M Na2S04 10% at 400-450 nm [99]... 

Well now, the proposed co-reprecipitation method [45] and visible-light-driven photocatalytic reduction method [53] have been established for the purpose of these kinds of core/shell type hybridized NCs composed of PDA NC and noble metal NP, and both processes have been further improved to extend to another type hybridized NCs, respectively [50, 54], Typical core/shell type hybridized NPs were first reported by Halas and Caruso research groups [70, 71, 73, 84, 87]. A great number of fine gold (Au) NPs as Au shell were deposited densely on the surface of silica NPs, which are spherical and uniform size. The LSP speetra were continuously blue-shifted with increasing the thickness of Au shell, and some optoelectronic applications have been now presented such as a substrate for surface enhanced Raman spectrum (SERS) measurement, chemical- and bio-sensors, etc. Silica NPs, however, are core as a template to fabricate core/sheU type hybridized nanostructure, and there is no something like optoelectronic interaction through core/shell hetero nano-interface in this case. 

Porous membranes (low H2 selectivity) are used as substrate onto which a very thin but continuous film of a selective metal, generally Pd-based, is deposited. Dense composite membranes are also fabricated by sintering together powders of highly H2 permeable metals (Pd, Pt, Nb,Ta,1i, V, Zr and their alloys) with powders of a second metal or alloy which is non-permeable to H2 (Mundschau, 2005), having the function of providing the mechanical support. Some fundamental science related to the H2 separation using dense composite membranes is reported by Mundschau (2008). 

Sandstone. Sandstone wheels were once quarried extensively for farm and industrial use, and special grades of stone for precision honing, sharpening, and lapping are a small but important portion of today s abrasive industry. Production of honing and sharpening stones from deposits of dense, fine grain sandstone in Arkansas account for 76% of the value (about 2 million in 1987) and 88% of the total quantity of such stones in the United States (4). 

The result is the formation of a dense and uniform metal oxide layer in which the deposition rate is controlled by the diffusion rate of ionic species and the concentration of electronic charge carriers. This procedure is used to fabricate the thin layer of soHd electrolyte (yttria-stabilized 2irconia) and the interconnection (Mg-doped lanthanum chromite). 

Interfdci l Composite Membra.nes, A method of making asymmetric membranes involving interfacial polymerization was developed in the 1960s. This technique was used to produce reverse osmosis membranes with dramatically improved salt rejections and water fluxes compared to those prepared by the Loeb-Sourirajan process (28). In the interfacial polymerization method, an aqueous solution of a reactive prepolymer, such as polyamine, is first deposited in the pores of a microporous support membrane, typically a polysulfone ultrafUtration membrane. The amine-loaded support is then immersed in a water-immiscible solvent solution containing a reactant, for example, a diacid chloride in hexane. The amine and acid chloride then react at the interface of the two solutions to form a densely cross-linked, extremely thin membrane layer. This preparation method is shown schematically in Figure 15. The first membrane made was based on polyethylenimine cross-linked with toluene-2,4-diisocyanate (28). The process was later refined at FilmTec Corporation (29,30) and at UOP (31) in the United States, and at Nitto (32) in Japan. 

Flame spray metallising is widely used for the protection of metal against corrosion, especially for in situ protection of stmctural members. The principal metal used for spraying of plastics is sine. Aluminum and copper are also used. If the distance from the part is too great, the zinc solidifies before it touches the part and adhesion is extremely poor. If the molten zinc oxidizes, conductivity and adhesion are poor. If the distance is too short, the zinc is too hot and the plastic warps or degrades. These coatings are not as dense as electrically deposited coatings because of numerous pores, oxide inclusions, and discontinuities where particles have incompletely coalesced. 

Miscellaneous. Electron beams can be used to decompose a gas such as silver chloride and simultaneously deposit silver metal. An older technique is the thermal decomposition of volatile and extremely toxic gases such as nickel carbonyl [13463-39-3] Ni(CO)4, to form dense deposits or dendritic coatings by modification of coating parameters. 

Fine-grained deposits are usually obtained from complex ion solutions, eg, cyanide, or using certain addition agents. These deposits are less pure, less dense, and exhibit higher electrical resistivities because of the presence of foreign material. 

In addition to conventional petroleum (qv) and heavy cmde oil, there remains another subclass of petroleum, one that offers to provide some rehef to potential shortfalls in the future supply of Hquid fuels and other products. This subclass is the bitumen found in tar sand deposits (1,2). Tar sands, also known as oil sands and bituminous sands, are sand deposits impregnated with dense, viscous petroleum. Tar sands are found throughout the world, often in the same geographical areas as conventional petroleum. 

The bitumen in the Athabasca deposit, which has a gravity on the API scale of 8°, is heavier than water and very viscous. Tar sand is a dense, soHd material, but it can be readily dug in the summer months during the winter months when the temperatures plunge to —45° C, tar sand assumes the consistency of concrete. To maintain acceptable digging rates in winter, mining must proceed faster than the rate of frost penetration if not, supplemental measures such as blasting are required. 

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