Activity alloys

This research was carried ont in two parts. The first one explored the relationships between alloy structnre, alloy activation and the resulting catalyst, and the second one looked at the nse of sterically controlled Ni ensembles for improved reaction... 

The number of such examples, however, is not high. In many other examples of advanced-performance materials, such as DuPont s Kevlar and Allied Signal s SPECTRA, the volume applications associated with system-for-system substitution has not yet occurred at a level necessary to pay back the development and commercialization costs already expended. High-performance ceramics is another area in which the early promise has yet to materialize. The consequences of Eckstut s life-cycle dynamics have been overcapacity and severe rationalization in high-performance carbon fiber businesses, some specialty alloy activities, and high-performance polymer composites. Thus, with critical technologies that involve advanced-performance materials, we need to better understand how to exploit their value in a commercially viable way. 

Runnalls, O. J. C. Alloying Active Metals with Aluminium or Beryllium. 

We know already that metals differ in their ability to form 2C and 3C complexes. In general, under the conditions when solely the exchange reactions are running, formation of 2Ca/i complexes is always easier than formation of 3Cay complexes. However, the results obtained with alloys (active + inactive metals) show that we have to discern two different types of 2C complexes ... 

Yang, C.M., El-Merraoui, M., Seki, H., and Kaneko, K. Characterization of nitrogen-alloyed activated carbon fiber. Langmuir 17, 2001 675-680. 

Metal cations can also affect the activity of Raney nickel catalysts. The presence of three to ten per cent of chromium or molybdenum in the Raney nickel alloy results in a general increase in the activity of the catalyst prepared from this alloy. Activation of nickel catalysts has also been accomplished by treating them with aqueous solutions of chromium chloride. Another effective promoter for Raney nickel is platinum which increases the activity of this catalyst for the... 

Hydrogenation of several aromatic compounds was conducted using the activated hydrogen storage alloy MmNi jCoq AIq gH at a relatively high than temperature (160-240°C) under a nitrogen atmosphere. Selective reduction was observed with several aromatic compounds such as biphenyl and 2-phenylpyridine. The details and mechanistic aspects of this reaction were discussed by referring to the results of the reduction reaction with the alloy activated by deuterium,... 

Conversions to methanol over catalysts produced from copper-thorium alloys activated in air at ambient conditions (from ref.17). 

The MRT Purifier, developed for Tecnimont-KT in the framework of FISR project, has been designed to house five membrane modules and operate at 450°C and up to 25 barg. Each module consists of two double sided, planar 30 cm X 12 cm membrane panels welded in series. Each panel has a palladium (Pd) alloy active membrane area of 0.03 m per side for a total installed membrane area of 0.6 m in the purifier. The modules are housed in a rectangular core which, along with the inlet distributor, promotes uniform reformate flow across the membrane modules. The core assembly (Fig. 3.11) is housed inside a pressure vessel. 

Ternary and Higher Alloys Alloys of the systems Ag—Cu—Sn, Ag—Cu—Zn, and Ag—Cu—CU3P are used as solders and brazes. Ag—Cu—P solder alloys can be applied without flux. Ti-containing solder alloys (active solders) allow di-... 

The addition of other metals to the heterogeneously cobalt-catalyzed reaction can have a beneficial effect on hydroformylation. For example, small amounts of ruthenium added to a carbon-supported cobalt catalyst (Co/AC) increased activity as well as Hb selectivity [64]. The effect was rationalized by the high dispersion and reducibUity of supported cobalt. When ruthenium was added, small particles of an unbalanced alloy were formed. These particles keep more CO in a nondisso-ciative state and lower the surface hydrogen pressure. This was in contrast to the related but uniformly distributed Pt-Co or Pd-Co alloys. Activity and regioselectivity increased with increased Ru loading. 

Pt-based alloys have been developed for many years to improve the catalytic activity of the oxygen reduction reaction and the methanol oxidation reaction, and reduce Pt loading in the catalyst layers of the PEM fuel cell cathode and anode. Great progress has been made in recent years in terms of alloy activity screening, alloy mechanism discovery, and alloy stability investigation. 

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