Spin-control

While many of the important reactions in radiation and photochemistry are fast, not all are diffusion-limited. The random flight simulation methodology has been extended to include systems where reaction is only partially diffusion-controlled or is spin-controlled [54,55]. The technique for calculating the positions of the particles following a reflecting encounter has been described in detail, but (thus far) this improvement has not been incorporated in realistic diffusion kinetic simulations. Random flight techniques have been successfully used to model the radiation chemistry of aqueous solutions [50] and to investigate ion kinetics in hydrocarbons [48,50,56-58]. 

It is also possible to prepare V205-based vanadium nanotubes from surfactant solution. They are formed using oxotriisopropoxovanadium(V) and have been found to have unique electronic properties that can be controlled by electron doping [5], In fact, these tubes offer the possibility of spin control and, therefore, have significant potential in the development of spintronic devices. 

E. B. Krissinel and N. V. Shokhirev, Differential approximation of spin-controlled and anisotropic diffusional kinetics (Russian), in Siberian Academy Mathematical Methods in Chemistry, Preprint 30 (1989) Diffusion-controlled reactions 22, in DCR User s Manual 11-20-1990. 

Kohn R (2008) Reactivity of chromium complexes under spin control. Angew Chem Int Ed... 

Spinning the products of combustion helps greatly. Sometimes there is too much spin, but more often there is not enough. Even with the degree of spin controlled to give a flat temperature profile in the combustion chamber, the pit bottom temperature may be 100 to 200 °F (55 to 110 °C) hotter at the opposite end than at the burner end. 

If a long furnace is fired from one end, the cooling gases set up temperature differentials that affect the load heating rate. (See fig. 5.6.) Attaining a flat temperature profile along the length of a one-end-fired furnace requires burners with adjustable spin controlled by AT sensors. (See chap. 6.)... 

Example (a) In a one-way, top-fired soaking pit without spin, control of its poc will have an end-to end temperature difference of about 175°F (97°C) at the time when the load is expected to be reliable, but with oxy-fuel firing and its lower mass circulation, the corresponding end-to-end temperature difference might be 400°F (222°C) or more. 

Example A 25 long x 10 wide soaking pit heating 36" x 36" x 90" high ingots (33 000 pounds each) can be heated from cold to ready to roll in 10 hr, with a cutback time of 2.2 hr with burners and controls for spin condol. Without spin-control burners... 

Spin control materials to absorb spilled materials are available conunerciaUy. Some materials are universal, and some are intended to not only absorb materials, but also to neutralize specific... 

Buchachenko, A.L. (2001) Magnetic isotope effect nuclear spin control of chemical reactions. J. Phys. Chem. A,... 

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