Platinum continued applications

Simultaneous and continuous measurements of extracellular pH, potassium K+, and lactate in an ischemic heart were carried out to study lactic acid production, intracellular acidification, and cellular K+ loss and their quantitative relationships [6, 7], The pH sensor was fabricated on a flexible kapton substrate and the pH sensitive iridium oxide layer was electrodeposited on a planar platinum electrode. Antimony-based pH electrodes have also been used for the measurement of myocardial pH in addition to their application in esophageal acid reflux detection. 

Since S03/H2S04 is clearly not the most desirable system for industrial applications, a formidable challenge is to find an oxidant that oxidizes Pt(II) much faster than S03 does, operates in an environmentally friendly solvent, and can be (like SVI/SIV) reoxidized by oxygen from air. Ideally, the reduced oxidant would get reoxidized in a continuous process, such that the oxidant acts as a redox mediator. In addition, the redox behavior has to be tuned such that the platinum(II) alkyl intermediate would be oxidized but the platinum(II) catalyst would not be completely oxidized. Such a system that efficiently transfers oxidation equivalents from oxygen to Pt(II) would be highly desirable. A redox mediator system based on heteropolyacids has been reported for the Pt-catalyzed oxidation of C-H bonds by 02, using Na8HPMo6V6O40... 

One energy application of methanol in its early stages of development is the direct methanol fuel cell (DMFC). A fuel cell is essentially a battery in which the chemicals are continuously supplied from an external source. A common fuel cell consists of a polymer electrolyte sandwiched between a cathode and anode. The electrodes are porous carbon rods with platinum... 

Combinations op Platinum.—This metal is capable of uniting with most of the non-mctallic elements with several of them it readily combines, whilst with others the conditions requisite to effort the combination are varied. In a practical point of view, however, these are uninteresting, os no particular application of thorn has been made, with, perhaps, tho exception of the bichloride, which is in continued request in the laboratory, and in some cases in tho potter s ait, for producing bright steel greys. Some of the compounds thus produced, more especially the chloride, enter into the formation of other well-marked bodies of a compound. saline nature, wherein the platinum compound remains intact, and occupying as it wore the part of a radical in the new salt. 

PGM catalyst technology can also be applied to the control of emissions from stationary internal combustion engines and gas turbines. Catalysts have been designed to treat carbon monoxide, unbumed hydrocarbons, and nitrogen oxides in the exhaust, which arise as a result of incomplete combustion. To reduce or prevent the formation of NO in the first place, catalytic combustion technology based on platinum or palladium has been developed, which is particularly suitable for application in gas turbines. Environmental legislation enacted in many parts of the wodd has promoted, and is expected to continue to promote, the use of PGMs in these applications. 

Another example of the application of the principles of coulometric titrations to a continuous on-stream analyzer is the moisture analyzer developed by Kei-del.18 It illustrates one of the outstanding advantages of the coulometric generation of a titrant namely, an intermediate is produced as a titrant that would not be available in standard solutions. The principle of the moisture analyzer is to place a phosphoric acid solution between two closely spaced platinum electrodes (helically wound in a glass tube). When current is passed between the two electrodes, the water in the phosphoric acid is electrolyzed... 

The principal application of NMR in the study of the compounds of the platinum group metals is likely to continue to be in structure de-... 

In the field of hydrocarbon conversions, N. D. Zelinskii and his numerous co-workers have published much important information since 1911. Zelinskii s method for the selective dehydrogenation of cyclohexanes over platinum and palladium was first applied to analytical work (155,351,438,439), but in recent years attempts have been made to use it industrially for the manufacture of aromatics from the cyclohexanes contained in petroleum. In addition, nickel on alumina was used for this purpose by V. I. Komarewsky in 1924 (444) and subsequently by N. I. Shuikin (454,455,456). Hydrogen disproportionation of cyclohexenes over platinum or palladium discovered by N. D. Zelinskii (331,387) is a related field of research. Studies of hydrogen disproportionation are being continued, and their application is being extended to compounds such as alkenyl cyclohexanes. The dehydrocyclization of paraffins was reported by this institute (Kazanskil and Plate) simultaneously with B. L. Moldavskil and co-workers and with Karzhev (1937). The catalysts employed by this school have also been tested for the desulfurization of petroleum and shale oil fractions by hydrogenation under atmospheric pressure. Substantial sulfur removal was achieved by the use of platinum and nickel on alumina (392). 

After retiring in 1975, he continued active research but moved to a new application of catalytic chemistry. He synthesized new platinum-containing molecules that are derivatives of the same family known as dv-platinum, which was discovered to have antitumor activity. Turkevich s candy-coated cfv-platinum derivatives were also useful clinical agents in cancer chemotherapy. Even at the end of his life, Turkevich was still doing experiments with colleagues in medicine and chemistry. 

Deposition or formation of a metallic film is an important aspect in microfabrication. For traditional IC and electronic devices, metal films such as aluminum or copper film provide the electrical contact and connection from the device to external circuitry or equipment. In this circumstance, the line width and its electrical continuity are of interest. With the advancement of using microfabricated devices in chemical and biological application, formation of metallic films, such as gold, platinum, and others, becomes necessary. The formation of this metal film can be accomplished by thick or thin film techniques. 

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