External confinement

Chemical and Spectroscopic Probes of Internal Versus External Confinement of Metal Guests... 

The process of loading zeolites with organometallie complexes always brings to the forefront the question of internal versus external confinement of the metal guest. In this paper we present some experiments based on size exclusion, metal loading and intrazeolite chemistry which in conjunction with FT-FAR-IR, EPR and UV-visible reflectance spectroscopy, critically probe the question of internal versus external location for the case of five representative organometallics,... 

Thus by using Co2(C0)8 as a representative organometallic guest, and a combination of size exclusion experiments and intrazeolite oxidation chemistry, as probed through the far-IR cation spectra of sodium and acid faujasites and A-zeolites, one is able to distinguish between internal and external confinement of the metal guest(s) in the zeolite. 

Theta-pinch concepts belong to the so called high-0 devices since the ratio of the kinetic pressure of the plasma to the pressure of the external confining magnetic field is relatively high ... 

Crustaceans, like all arthropods, must periodically shed their external, confining exoskeletons and take up air or water to expand their new and larger exoskeletons in order to grow in size. The problem of how to increase in body size is even more formidable for crustaceans (compared to insects) due to their mineralized, relatively... 

Damages of concrete piers as shown in Fig. 1(a) were caused by lack of flexural capacity or shear capacity of existing structures against seismic forces. Particularly, extensive damages were observed at the base part of the pier and at the termination of longitudinal re-bars at mid-height. Therefore, in piers with inadequate lateral reinforcement, it is imperative to provide additional external confinement to insure ductility of the piers. 

Figure 3.9 Setup used for isothermal stress-strain testing and constrained shape recovery testing. The fixture provided a 1-D external confinement and the furnace was used to trigger the shape memory effect by heating the specimen above its Tg. The MTS machine was used to record the resuiting recovery stress...

Shehata, I.A.E.M., Carneiro, L.A.V., and Shehata, L.C.D. (2002), Strength of short concrete columns confined with CFRP sheets . Mater. Struct., 35, 50-58 Teng, J.G., Huang, Y.L., Lam, L., and Ye, L.P. (2007), Theoretical model for fiber reinforced polymer-confined concrete , J. Comp. Const., 11(2), 201-210 Toutanji, H. A. (1999), Stress-strain characteristics of concrete columns externally confined with advanced fiber composite sheets , ACI Mater. J., 96(3), 397 04 van Erp, G.M., Heldt, T.J., Cattell, C.L., and Marsh, R. (2002), A new approach to fibre composite bridge structures , 17th Australasian Conference on the Mechanics of Structures and Materials, ACMSM17, Gold Coast, Queensland, Australia, 12-14, 2002. pp. 37 5... 

Among several recent advances, NiTi SMA wires have been pretensioned before application and then wrapped around a concrete column as external confining reinforcement while being at the martensite phase. Then, by raising the temperature of the wire, transformation to the austenite phase takes place. In this manner, the wire recovers its original shape, and stresses are... 

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