Inorganic additives metal oxides

Chemical Properties. In addition to the reactions Hsted in Table 3, boron trifluoride reacts with alkali or alkaline-earth metal oxides, as well as other inorganic alkaline materials, at 450°C to yield the trimer trifluoroboroxine [13703-95-2] (BOF), MBF, and MF (29) where M is a univalent metal ion. The trimer is stable below — 135°C but disproportionates to B2O2 and BF at higher temperatures (30). 

Antimicrobial agents are used where there is a need to inhibit bacterial and fungal growth. The additives can consist of copper, germanium, zinc and zinc compounds, metal oxides or sulfides, metal zeofltes, as well as silver and copper oxide-coated inorganic core particles (154—159) (see Industrial ANTIMICROBIAL AGENTS). 

The addition of a second species can cause a decrease in charge recombination and an increase in the TiOz photocatalytic efficiency. Such behavior was examined by loading a series of species on the surface or into the crystal lattice of photocatalysts inorganic ions [148-152], noble metals [153,154], and other semiconductor metal oxides [155], It was thus proven that modifications produced by these species can change semiconductor surface properties by altering interfacial electron-transfer events and thus the photocatalytic efficiency. 

In addition to the inorganic hydroxyl groups which are exposed on many mineral surfaces (metal oxides, phyllo-silicates and amorphous silicate minerals) we need to consider the particular features relating to charge on the silica surfaces of layer silicates. 

In addition to silica and clay minerals, the subsurface contains a variety of minerals (e.g., oxides, carbonates), which may react with organic and inorganic contaminants. GiUces (1990), summarizing the properties of the metal oxides in earth... 

There have been numerous investigations into the subsequent modification of bacterial and wood nanocelluloses. The additives range from other polysaccharides, albuminoids such as gelatine, different types of monomers and synthetic polymers, to metals, metal oxides, and inorganic fibers. On the... 

A more recent trend in polymer materials research is the hybridization of cellulosic polysaccharides with inorganic compounds natural and synthetic layered clays, silica, zeolites, metal oxides, and apatites are employable as nanoscale components. In addition, if mesoscopic assemblies such as liquid-crystalline ordering are used in the construction of new compositional systems, the variety of functionalized cellulosic materials will be further expanded. 

Different methods have been used to deposit microporous thin films, including solgel, pyrolysis, and deposition techniques [20], Porous inorganic membranes are made of alumina, silica, carbon, zeolites, and other materials [8], They are generally prepared by the slip coating method, the ceramic technique, or the solgel method (Section 3.7). In addition, dense membranes are prepared with metals, oxides, and other materials (Chapter 2). 

Synthesis forms a vital aspect of the science of nanomaterials. In this context, chemical methods have proved to be more effective and versatile than physical methods and have therefore, been employed widely to synthesize a variety of nanomaterials, including zero-dimensional nanocrystals, one-dimensional nanowircs and nanotubes as well as two-dimensional nanofilms and nanowalls. Chemical synthesis of inorganic nanomaterials has been pursued vigorously in the last few years and in this article we provide a perspective on the present status of the subject. The article includes a discussion of nanocrystals and nanowires of metals, oxides, chalcogenides and pnictides. In addition, inorganic nanotubes and nanowalls have been reviewed. Some aspects of core-shell particles, oriented attachment and the use of liquid-liquid interfaces are also presented. 

High-oxygen, nitrogen-free organic compounds (C, H, 0) are blended with inorganic oxidisers. The fuels used are, for example, tri or dicarboxylic acids (e.g. citric acid, tartaric acid, fumaric acid) or similar compounds. The oxidisers used are especially perchlorates and chlorates with additional assistance from metal oxides. This enables any formation of NOx to be excluded. 

The lowering of the temperature of reduction by H2 of numerous metal oxides by addition of a transition metal is well documented and may be attributed to spillover (7,8,62). Among all the metal dopants added, Pt and Pd are seen to be the most efficient and have been the most often studied. It should be noted that spillover does not only give rise to the reduction of solid or adsorbed phases oxidations of inorganic compounds such as UF4 (as well as carbon) can occur when Pt is present and the sample is exposed to oxygen (63-65). 

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