Colored golds

Steel Colored Steel Gold Colored Gold... 

T-2 can be used instead of 6T-3 for a cooler color. Gold tone modifier ... 

Table 3.4. Commonly Used Alloys for Colored Golds...

Fig. 3. Crystal structure of H. influenzae HSIU12V12 (Sousa et al., 2000). (A) Ribbon diagram of HslUV complex in side view. (B) Top view of the same HslUV complex. HslU is colored gold except for a single protomer in each hexameric ring which is colored white. HslV is colored blue except for one protomer in each ring, where one is colored pink and the other red.

Features Exhibits two-color play (blue absorp. color, gold reflection color) Properties Particle size 18 bulk dens. 13 Ib/tf Dynacolor GB [Engelhard]... 

Gold nanoparticles (2.5-7.5 nm diameter) were obtained by Martino and others [402] by reduction of AUCI4 via lithium borohydride in tetrahydrofuran in the reverse micelle system DDAB (didodecyldimethylammonium bromide)/toluene. A purple-colored gold colloid was observable. The particles were encapsulated by silica gels formed in the micellar system by hydrolysis-condensation of TEOS or a prehydrolyzed TEOS, already added in the system. Gelation of silica was achieved by the addition of tetrabutylammonium hydroxide (quicker in case of pre-hydrolyzed TEOS). The particle size was found to be independent of reaction stoichiometry, gel precursor type (TEOS/pre-hydrolyzed TEOS) and the washing step after synthesis. 

Figure 5.4 Interaction hot spots (colored gold) for a C=0 group probe within the binding site of tyrosine kinase, with the experimentally determined position of an oxindole inhibitor...

Gold salts oxidize acetic acid solutions of benzidine to benzidine blue which is a quinoneimine type of dyestuff (compare page 283). Colored gold hydrosols are produced at the same time. Considerable quantities of heavy metals or alkali salts flocculate the reaction products and so prevent the formation of the sols and consequently impair the test. Platinum salts and oxidants which act on benzidine must be absent. 

Figure 23 Surface of the poliovirus capsid showing the 60 protomeric subunits. The subunits are texture mapped by the proper of radial height. Those parts that are protruding are colored gold, while the surface parts that are lower are colored in the blue range, giving a -ea level topography to the representation. The subunits are created by a spherical harmonic surface at order (Image courtesy of...

There is a high electron density in the 3d band a few electron volts below the Fermi level. Cu preferentially absorbs blue light as these 3d electrons make transitions to 4s states giving Cu its characteristic reddish color. Allo)nng Cu with Zn shifts the absorption edge giving brass its yellowish color. Gold s yellow color is the result of similar interband transitions. 

Nanoparticles of usually yellow gold and gray silicon are red in color. Gold nanoparticles melt at much lower temperatures (300 °C for 2.5 nm size) than the gold slabs (1064 °C) [3]. Also, the absorption of solar radiation in photovoltaic cells is much higher in materials composed of nanoparticles than it is in thin films of continuous sheets of material (i.e., the smaller the particles, the greater the solar absorption). 

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