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First experiences with application

The first experiments with the thermal electric engine were conducted in Russia in 1929 by its inventor, Valentin P. Glushko, who later became a world-famous authority in rocket propulsion. For more than forty years, the United States and Russia have devoted many resources to research and development of various kinds of EREs. First tested in space by the Russians in 1964, these engines have found some limited applications in modern space technology. For more than two decades Russian weather and communication satellites have regularly used electric rocket engines for orbital stabilization. The first spacecraft to employ ERE for main propulsion was the American asteroid exploration probe Deep Space 1, launched in 1998. The performance of... [Pg.1076]

Our first experience with hydrocyclones was with pilot plant trials of the Serck-Baker Oilspin developed as a result of an extensive research program conducted at Southampton U. J While these tests, carried out oo the Murchison and Hutton platforms in early 1983, were not an unqualified success, they demonstrated the equipment s potential and enough encouragement for us to commit to die first Mi-scale commercial application of the Vortoil four-t in-one 35-nun (l.4-in. hydrocyclone later that year. [Pg.225]

Christiane Gottschalk, Dr.-Ing. in environmental engineering, made her first experience with ozone in the year 1987 and has continued working with ozone in research and development in drinking water treatment at the Technical University Berlin and semiconductor applications at... [Pg.201]

Silicon is undoubtedly the material which has been most often applied for microfluidic applications, especially in the field of analysis systems. Detailed information has also been obtained for a number of microreactor components and some of them are already commercially available. Even more striking, first experiments with integrated systems have been reported by DuPont [8]. However, silicon components did not find a broad use in industrial applications, especially in the field of synthetic chemistry. For this purpose, future developments have to address a broader variety of components than those mentioned above, including e.g. heat exchangers, extractors and others, and the feasibility of the fabrication of integrated systems has to be demonstrated in more detail. [Pg.249]

Yet for the hme being, it is still unclear in how far functionalized carbon nanotubes are toxic. The pristine tubes possess a normegligible cytotoxicity, which is, among others, due to their insolubihty and the residual catalyst contained. First experiments with functionalized derivatives indicate, however, that at least this toxicity is markedly decreased once the surface has been modified. Anyhow, further studies are required here, and real applications in the medical sector are still a vision for the future. [Pg.273]

From the first experiences with the application of fibre-reinforced polymers up to modern buildings... [Pg.9]

You have already had considerable experience with carbanionic compounds and their applications in synthetic organic chemistry The first was acetyhde ion m Chapter 9 followed m Chapter 14 by organometallic compounds—Grignard reagents for example—that act as sources of negatively polarized carbon In Chapter 18 you learned that enolate ions—reactive intermediates generated from aldehydes and ketones—are nucleophilic and that this property can be used to advantage as a method for carbon-carbon bond formation... [Pg.886]

One of the major uses of molecular simulation is to provide useful theoretical interpretation of experimental data. Before the advent of simulation this had to be done by directly comparing experiment with analytical (mathematical) models. The analytical approach has the advantage of simplicity, in that the models are derived from first principles with only a few, if any, adjustable parameters. However, the chemical complexity of biological systems often precludes the direct application of meaningful analytical models or leads to the situation where more than one model can be invoked to explain the same experimental data. [Pg.237]

An appreciation of statistical results can be gained from a study conducted to support the first application of computer control for an ethylene oxide production unit at Union Carbide Corporation in 1958. For the above purpose, twenty years of production experience with many units was correlated by excellent statisticians who had no regard for kinetics or chemistry. In spite of this, they did excellent, although entirely empirical work. One statement they made was ... [ethane has a significant effect on ethylene oxide production.] This was rejected by most technical people because it did not appear to make any sense ethane did not react, did not chemisorb, and went through the reactor unchanged. [Pg.114]

Interesting developments were also taking place in the field of thermosetting resins. The melamine-formaldehyde materials appeared commercially in 1940 whilst soon afterwards in the United States the first contact resins were used. With these materials, the forerunners of today s polyester laminating resins, it was found possible to produce laminates without the need for application of external pressure. The first experiments in epoxide resins were also taking place during this period. [Pg.7]

Because these variables have a very pronounced effect on the current density required to produce and also maintain passivity, it is necessary to know the exact operating conditions of the electrolyte before designing a system of anodic protection. In the paper and pulp industry a current of 4(KX) A was required for 3 min to passivate the steel surfaces after passivation with thiosulphates etc. in the black liquor the current was reduced to 2 7(X) A for 12 min and then only 600 A was necessary for the remainder of the process . From an economic aspect, it is normal, in the first instance, to consider anodically protecting a cheap metal or alloy, such as mild steel. If this is not satisfactory, the alloying of mild steel with a small percentage of a more passive metal, such as chromium, molybdenum or nickel, may decrease both the critical and passivation current densities to a sufficiently low value. It is fortunate that the effect of these alloying additions can be determined by laboratory experiments before application on an industrial scale is undertaken. [Pg.267]

The first documented use of sUicone as biomaterial was silicone mbber tubing as shunts for treatment of hydrocephalus in about 1955. From 1960 to 1990, the biomedical application of sUicone mbber was steadUy grown. One of the most well-known silicone product is the Norplant contraceptive implant. The first clinical experiment with this device was reported in 1966. FDA approved its use in 1990. [Pg.246]

The appearance of electrochemical batteries provided an impetus in research into practical applications of electric current. The first prototype of electric telegraph appeared in 1804. In 1838, Jacobi experimented with a battery-driven motorboat on the Neva River not far from St. Petersburg. These achievements led to rapid development of the theory and practice of electrical engineering, and the seventh decade of that century saw the appearance of a revolutionary new power source the electromagnetic generator (Werner von Siemens, 1866), which soon surpassed their predecessors in both electrical and economic parameters. [Pg.694]

Stationary phase. Supelcosil Cig ABZ (Supelco Scientific, Bellefonte, PA, USA) was the most often employed support and gave the best correlations. This stationary phase should be selected in a first instance with a geometry adapted to the application for conventional gradient experiments, supports of 150X4.6 mm, 5 pm represent a good choice while a shorter column (i.e. 50 mm or lower) with smaller particle size (i.e. 3-3.5 pm) must be preferentially selected for fast gradient analysis. [Pg.346]

The PRISMA model was developed by Nyiredy for solvent optimization in TLC and HPLC [142,168-171]. The PRISMA model consists of three parts the selection of the chromatographic system, optimization of the selected mobile phases, and the selection of the development method. Since silica is the most widely used stationary phase in TLC, the optimization procedure always starts with this phase, although the method is equally applicable to all chemically bonded phases in the normal or reversed-phase mode. For the selection of suitable solvents the first experiments are carried out on TLC plates in unsaturated... [Pg.866]

Beeck at Shell Laboratories in Emeryville, USA, had in 1940 studied chemisorption and catalysis at polycrystalline and gas-induced (110) oriented porous nickel films with ethene hydrogenation found to be 10 times more active than at polycrystalline surfaces. It was one of the first experiments to establish the existence of structural specificity of metal surfaces in catalysis. Eley suggested that good agreement with experiment could be obtained for heats of chemisorption on metals by assuming that the bonds are covalent and that Pauling s equation is applicable to the process 2M + H2 -> 2M-H. [Pg.3]


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First application

First experiments

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