INDEX platinum

Lang B, Joyner R W and Somorjai G A 1972 LEED studies of high index crystal surfaces of platinum Surf. Sc 30 440-53... 

Zirconium oxide increases the refractive index of some optical glasses, and is used for dispersion hardening of platinum and mthenium. Very fine zirconium oxide has been used for polishing glass but ceria seems to be preferred. 

A.n log ue Synthesis. Two notable examples, in which analogues have greater therapeutic indexes than the parent dmgs, have been identified in Phase I trials. These are carboplatin (29) and ado2elesin (37) (35). Carboplatin s approval was based on its comparable efficacy to cis-platinum (28) and its more favorable toxicity profile, ie, reduced and delayed episodes of emesis, reduced ototoxicity, etc. On the other hand, ado2elesin, a totally synthetic analogue of natural product CC1065, has demonstrated a similar potency and antitumor activity profile as its natural prototype but is devoid of the delayed death UabiUty associated with the parent dmg in animals (36). 

Since oxidation of methanol is an electrocatalytic reaction with different adsorption steps, interactions of the adsorbed species with the metallic surface are important. Using platinum single-crystal electrodes, it has been proven that the electrooxidation of methanol is a surface-sensitive reaction. The initial activity of the Pt(llO) plane is much higher than that of the other low-index planes, but the poisoning phenomenon is so rapid that it causes a fast decrease in the current densities. The... 

Panchenko A, Koper MTM, et al. 2004. Ab initio calculations of intermediates of oxygen reduction on low-index platinum surfaces. J Electrochem Soc 151 A2016-A2027. 

Markovic NM, Grgur BN, Ross PN. 1997. Temperature-dependent hydrogen electrochemistry on platinum low-index single-crystal surfaces in acid solutions. J Phys Chem B 101 5405-5413. 

Chang SC, Leung LWH, Weaver MJ. 1990. Metal crystallinity effects in electrocatalysis as prohed hy real-time ETIR spectroscopy electrooxidation of formic acid, methanol, and ethanol on ordered low-index platinum surfaces. J Phys Chem 94 6013-6021. 

Henero E, Franaszczuk K, Wieckowski A. 1994. Electrochemistry of methanol at low index crystal planes of platinum An integrated voltammetric and chronoamperometric study. J Phys Chem 98 5074-5083. 

Sun SG, Clavilier J. 1987. Electrochemical study on the poisoning intermediate formed from methanol dissociation at low index and stepped platinum surfaces. J Electroanal Chem 236 95-112. 

Xia XH, Liess HD, Iwasita T. 1997. Early stages in the oxidation of ethanol at low index single crystal platinum electrodes. J Electroanal Chem 437 233-240. 

Chang S-C, Weaver MJ. 1991. Influence of coadsorbed bismuth and copper on carbon monoxide adlayer stmctures at ordered low-index platinum-aqueous interfaces. Surf Sci 241 11-24. 

Chrzanowski W, Wieckowski A. 1997. Ultrathin films of ruthenium on low index platinum single crystal surfaces An electrochemical study. Langmuir 13 5974-5978. 

Nakamura M, Shibutani K, Hoshi N. 2007. In-situ flow-cell IRAS observation of intermediates during methanol oxidation on low-index platinum surfaces. ChemPhysChem 8 1846-1849. 

Markovic NM, Adzic RR, Cahan BD, Yeager EB. 1994. Structural effects in electrocatalysis— Oxygen reduction on platinum low-index single-crystal surfaces in perchloric-acid solutions. J Electroanal Chem 377 249-259. 

MarkovicNM, Gasteiger HA, Ross PN. 1995. Oxygen reduction on platinum low-index singlecrystal surfaces in sulphuric acid solution Rotating Ring-Pt(/iA /) Disk Studies. J Phys Chem 99 3411-3415. 

Fig. 2. Relaxation modulus G(t) of a set of polydimethylsiloxane samples with increasing extent of crosslinking plotted against time of crosslinking. The linear PDMS chains (Mn 10 000, polydis-persity index 2) were endlinked with a four-functional silane crosslinker catalyzed by a platinum compound. Samples with different extent of reaction were prepared by poisoning the reaction at different times. The actual extent of reaction was not determined. Two of the samples are clearly before the gel point (LST) and two beyond. The third sample is very close to the gel point. Data of Chambon and Winter [5] evaluated by Baumgartel and Winter [8]...

Generally, when two phases are in electronic equilibrium, eoifa — fa) = Hi — ji 2- In our case, the wire I is in equilibrium with the metal M, the latter is in equilibrium with the redox couple, and the platinum electrode II is in equilibrium with the reference couple (index ref ). 

Prior to solving the structure for SSZ-31, the catalytic conversion of hydrocarbons provided information about the pore structure such as the constraint index that was determined to be between 0.9 and 1.0 (45, 46). Additionally, the conversion of m-xylene over SSZ-31 resulted in a para/ortho selectivity of <1 consistent with a ID channel-type zeolite (47). The acidic NCL-1 has also been found to catalyze the Fries rearrangement of phenyl acetate (48). The nature of the acid sites has recently been evaluated using pyridine and ammonia adsorption (49). Both Br0nsted and Lewis acid sites are observed where Fourier transform-infrared (FT IR) spectra show the hydroxyl groups associated with the Brpnsted acid sites are at 3628 and 3598 cm-1. The SSZ-31 structure has also been modified with platinum metal and found to be a good reforming catalyst. 

Polymeric alkene ozonides are shock-sensitive that of trans -2-butene exploded when exposed to friction in a ground glass joint. The use of GLC to analyse crude ozonisation products is questionable because of the heat-sensitivity of some constituents [4], Ozonides are decomposed, sometimes explosively, by finely divided palladium, platinum or silver, or by iron(II) salts [5]. Individually indexed compounds are ... 

Thousands of platinum complexes have been synthesized and tested in recent years, and the pace of research remains very fast. The effort has yielded a number of compounds that exhibit higher activity, better selectivity, and/or increased therapeutic index compared to cisplatin. Some of these drugs are discussed herein. 

Copper high Miller index, 26 12 Copper oxide, 27 184-187, 199 as adsorbent, 21 44 on alumina, 27 80-85 -manganese oxide, 27 91, 92 oxidation of CO over, 24 86 -platinum catalyst, 27 86-88 propylene oxidation, 30 141 Coprecipitation, perovskite preparation, 36 247-250... 

The shape of the single crystal obtained by the method described above is a sphere with several flat facets as drawn in Fig. 2-6. Usually seven large facets, which are assigned to seven of possible eight (111) surfaces, are seen on the apex positions of a cube. Five small facets, which are assigned to five of possible six (100) surfaces, are also seen on the center of the faces of a cube. The missing (111) and (100) facets are supposed to be located where the shaft is attached. Figure 2—7 shows the relative positions of the three low index surfaces of platinum, which is a face-centered cubic lattice. 

Tlie low index svirfaces of platinum single crystals were examined with cyclic voltammetry. As mentioned in Chapter 2, single crystal surfaces are reconstructed by Pt-OH formation and reduction at a higher potential. Therefore, it was impossible to clean the surface thoroughly by potential steps without disturbing the surface structure. 

The structure of a polycrystalline electrode depends on its preparation. Usually toe rough electrodes are prepared by electrochemical deposition of a given metal onto a suitable substrate. Microcrystals present in polycrystaUine samples are randomly oriented on the surface. Most likely, not only basal but also higher MiUer-index planes should be considered in anticipating toe final structure of the electrode surface. It was shown that the stmcture of the platinized platinum surface depends strongly on toe platinization conditions, e.g., on toe concentration of the platinization... 

To determine the phase properties of the calcined bimetallic nanoparticles, a detailed x-ray diffraction (XRD) study was carried out. The XRD data of AuPt/C showed that the diffraction patterns for the carbon-supported nanoparticles show a series of broad Bragg peaks, a picture typical for materials of limited structural coherence. Nevertheless, the peaks are defined well enough to allow a definitive phase identification and structural characterization. The diffraction patterns of Au/C and Pt/C could be unambiguously indexed into an fcc-type cubic lattice occurring with bulk gold and platinum. We estimated the corresponding lattice parameters by carefully determining... 

Stepped surfaces withstand cyclic oxidation-reduction treatments (146) like [111] and some other low-index planes. Steps have either [311] or [110] structures. They are claimed to be the only places where orbital hybridization does not take place (136). No wonder that such platinum (138) and iridium (147) surfaces have enhanced activity in Cg dehydrocyclization of n-heptane. 

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