Grade transition

Lipponen, P. K., Kosma, V. M., Collan, Y., Kulju, T., Kosunen, O., and Eskelinen, M. 1990. Potential of nuclear morphometry and volume corrected mitotic index in grading transitional cell carcinoma of the urinary bladder. Eur. Urol. 77 333-337. 

Many polymerization reactions occur in batch reactors, and the product properties result from an integral average of reaction conditions. Even if the polymerization reactor is continuous, grade transitions are frequently required, which cause significant dynamic problems.14... 

M. Asteausuain, A. Bandoni, C. Sarmoria, and A. Brandolin, Simultaneous process and control system design for grade transition in styrene polymerization, Chem. Eng. Sci., 61, 3362-3378 (2006). 

Tetiker, M.D., Artel, A., Teymour, F., and Cinar, A. (2008). Control of grade transitions in distributed chemical reactor networks - an agent-based approach. Comput. Chem. Eng., 32, 1984-1994. 

Description Ethylene and comonomer are dissolved in solvent then fed into a reactor. Butene-1, octene-1 or both together can be used as comonomer. The reactor system operates in a solution phase, and, due to inherent low residence time (less than 2 minutes), it offers a tremendous flexibility for grade transitions and significant versatility for meeting product needs of a diverse market. 

A number of low-grade transition metal ores (for example, minerals containing nickel oxides) can be used as catalysts. Smuda has demonstrated that microwave or radiofrequency irradiation of a mixture of such ores with a carbon source initiates reduction of the oxide to metal. With this approach, poisoning the active sites of the catalyst will not be critical for the process since there will be a constant supply and generation of active catalyst with the feed material. In addition to well-known catalytic properties of nickel in organic reactions, it was also shown that Ni on carbon and other supports, catalyzes hydrodechlorination and dehydrochlorination of chlorinated organic waste streams [22-24],... 

COMPOSITION-GRADED TRANSITIONAL BUFFERING FILM/ELECTROCOPPER... 

STRUCTURE AND STABILITY OF COMPOSITION-GRADED TRANSITIONAL BUFFERING PHASE... 

Figure 21.7 Transmission electron micrograph (a) (x 88000) and electron diffraction pattern (b) of the composition graded transitional buffering fdm layered by double-graded process (1 copper electrode used 2 silver electrode used).

Figure 21.8 XPS spectra of the surface of composition graded transitional buffering film layered by double-graded process curve a, surface curve b, 1 min sputter curve c, 5 min sputter curve d, oxidized copper surface.

Figure 21.9 The proposed seetional model of a eomposition-graded transitional buffering film layered by double-graded proeess A, pure methane plasma polymer layer B, composition-graded layer of methane plasma polymer and metal C, sputtered metal layer with earbon contamination.

Clearly, this simple relationship does not accommodate many commonly observed phenomena such as the graded transitions in an homologous series with a transition from agonism to antagonism (Fig. 28.10). The term intrinsic activity introduced by Ariens provided a phenomenological descriptor for the relative ability of a drug to produce response relative to some standard on a scale of 0 to 1 ... 

Peucat J.J., Vidal P., Bemard-GrifBths J. and Condie K.C, 1988, Sr, Nd and Pb isotopic systematics in the Archaean low- to high-grade transition zone of southern India syn accretion vs, posr-accrerion granulites. y. C /., 97, 537—550. 

Zitlalpopoca-Soriano AG, Vivaldo-Lima E, FlOTes-Hacuahuac A (2010) Grade transition dynamic optimizatimi of the living nitroxide-medialed radical polymerization of styrene in a tubular reactor. Macromol React Eng 4 516-533... 

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