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Blacks, Metallic

The aqueous solution has a low conductivity, indicating that mercury(II) chloride dissolves essentially as molecules Cl—Hg—Cl and these linear molecules are found in the solid and vapour. A solution of mercury(II) chloride is readily reduced, for example by tin(ll) chloride, to give first white insoluble mercury(I) chloride and then a black metallic deposit of mercury, The complexes formed from mercury(II) chloride are considered below. [Pg.438]

Electrical Properties. (See Table 1.) A new family of ABS products exhibiting electrostatic dissipative properties without the need for nonpolymeric additives or fillers (carbon black, metal) is now also commercially available (2). [Pg.203]

In general, the chemistry of inorganic lead compounds is similar to that of the alkaline-earth elements. Thus the carbonate, nitrate, and sulfate of lead are isomorphous with the corresponding compounds of calcium, barium, and strontium. In addition, many inorganic lead compounds possess two or more crystalline forms having different properties. For example, the oxides and the sulfide of bivalent lead are frequendy colored as a result of their state of crystallisation. Pure, tetragonal a-PbO is red pure, orthorhombic P PbO is yeUow and crystals of lead sulfide, PbS, have a black, metallic luster. [Pg.67]

Stainless steels attacked by sulfate reducers show well-defined pits containing relatively little deposit and corrosion product. On freshly corroded surfaces, however, black metal sulfides are present within pits. Rust stains may surround pits or form streaks running in the direction of gravity or flow from attack sites. Carbon steel pits are usually capped with voluminous, brown friable rust mounds, sometimes containing black iron sulfide plugs fFig. 6.10). [Pg.136]

The lustrous, purple-black metallic sheen of resublimed crystalline iodine was first observed... [Pg.794]

High-temperature reduction of Na2Ti03 with hydrogen produces nonstoichiometric materials, Na jTi02 (jr = 0.20-0.25), called titanium bronzes by analogy with the better-known tungsten bronzes (p. 1016). They have a blue-black, metallic appearance with high electrical conductivity and are chemically inert (even hydrofluoric acid does not attack them). [Pg.964]

To a solution of 180 parts of -benzyl N-benzyloxycarbonyl-L-aspartvI-L-phenylalanine methyl ester in 3,000 parts by volume of 75% acetic acid is added 18 parts of palladium black metal catalyst, and the resulting mixture is shaken with hydrogen at atmospheric pressure and room temperature for about 12 hours. The catalyst is removed by filtration, and the solvent is distilled under reduced pressure to afford a solid residue, which is purified by re-crystallization from aqueous ethanol to yield L-aspartyl-L-phenylalanine methyl ester. It displays a double melting point at about 190°C and 245°-247°C. [Pg.104]

Unfortunately, investigations with ionic liquids containing high amounts of AlEtCl2 showed several limitations, including the reductive effect of the alkylaluminium affecting the temperature stability of the nickel catalyst. At very high alkylaluminium concentrations, precipitation of black metallic nickel was observed even at room temperature. [Pg.246]

Loft space between flat celling and unsealed fiber cement or black metal cladding to pitched roof Air space between fiber cement or black metal cladding with unsealed joints and low-emlsslvlty surface facing air space... [Pg.114]

Air space between fiber cement or black metal cladding with unsealed joints and hlgh-emlsslvlty lining... [Pg.114]

These are generally reserved for specialist applications, and are in the main more costly than conventional soap-based greases. The most common substances used as nonsoap thickeners are silica and clays prepared in such a way that they form gels with mineral and synthetic oils. Other materials that have been used are carbon black, metal oxides and various organic compounds. [Pg.879]

For many of the metals generated by one of the above three general methods, the finely divided black metals will settle after standing for a... [Pg.228]

Mo2(0R)6 compounds in hydrocarbon solvents rapidly polymerize acetylene to a black metallic-looking form of polyacetylene. Propyne is polymerized to a yellow powder, while but-2-yne yields a gelatinous rubber-like material (45). The detailed nature of these polymers is not yet known and the only molybdenum containing compounds recovered from these polymerization reactions were the Mo2(0R)6 compounds. When the reactions were carried out in the presence of pyridine/hexane solvent mixtures, simple adducts Mo2(0R)6(py)2(ac) were isolated for R = i-Pr and CH2-t-Bu, and ac = HCCH, MeCCH and MeCCMe (45,46). [Pg.250]

Osmium was discovered in 1803, at the same time as iridium, by Smithson Tennant (1761—1815). Several researchers, including Tennant, were curious about a black metallic... [Pg.158]

In fact, in 1972, Fujishima and Honda (10) demonstrated that O2 evolution on n-type Ti02 occurs as a photocurrent, proportional to the light intensity (Figure 1) of wavelengths less than 415 nm, i.e. for photon energies equal to or greater than the band gap of Ti02 3.0 eV. In this work and that of Ohnishi et al. (11) a platinum black metal cathode was connected in an external circuit to an indium contact on the back side of the photo-anode (see... [Pg.222]

This same oxide exists in a variety of other forms, such os a fibrous mass, with the fibres radiating from a centre, in which state it is termed the red hematite or fibrous iron ore. When the ore is an amorphous mass, it is termed compact iron, ore when mixed with clay and other earthy matters, red ochre when hard, and combined with silica, jaspery ore / whon in scales of a black metallic lustra, it is known as micaceous iron ore or iron glance. [Pg.407]

Investigation by X-ray methods 3 of the structure of samples of arsenolamprite from two different localities showed only partial agreement with that of metallic rhombohedral arsenic the differences may be attributed to the presence of impurity in the minerals, but could also be explained by the presence of a second allotropic modification corresponding to black metallic phosphorus (see p. 35). [Pg.33]

Dimercury(I) salts react with basic nitrogen compounds such as ammonia to form insoluble black products, which were originally considered to be dimercury(I) coordination compounds,76 but by X-ray examination it was shown that, in addition to finely dispersed black metallic... [Pg.1053]

Proceed as for silicon, using 50g of dry boron trioxide, 75g of sulfur, and lOOg of aluminum. About 7.5g of black metallic crystals (which scratch glass) are obtained. The thinnest crystals show a dark-red color by transmitted light... [Pg.3]

Mainly linear. If the periodic table is transformed into a spiral sculpture, it would be mainly solid. If a mobile periodic table is created, a linear, three-dimensional work of art would result. Famous artworks that resemble a mobile periodic table are the Alexander Calder mobiles. A good example is Untitled at the National Gallery of Art in Washington, D.C. Two red metal pieces represent the s elements, and six black metal pieces represent the p elements. [Pg.197]


See other pages where Blacks, Metallic is mentioned: [Pg.53]    [Pg.254]    [Pg.298]    [Pg.821]    [Pg.596]    [Pg.94]    [Pg.8]    [Pg.93]    [Pg.179]    [Pg.456]    [Pg.549]    [Pg.207]    [Pg.376]    [Pg.197]    [Pg.220]    [Pg.381]    [Pg.239]    [Pg.3]    [Pg.268]    [Pg.55]    [Pg.63]    [Pg.99]    [Pg.392]    [Pg.658]    [Pg.3]    [Pg.284]    [Pg.687]    [Pg.267]    [Pg.94]    [Pg.205]   


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Black metal

Black metal sulphide

Black powder-metal fire dust compositions

Carbon black metal-coordinated

Carbon black metal-coordination complex

Magnesium metal with carbon black

Metal carbon black

Microscopic metals metal blacks

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