Systemic History

Transmission electron microscopic observaiion reveals various morphologies of precipitates depending upon the constituents and composition of an alloy system, history of heat treatments etc. Typical examples are spherical precipitates found in Nl-Cr-Al system and cuboidal precipitates in Fe-Mo system [1]. The first question raised is what determines the shape of a precipitate. 

The impact of Ice Storm 98 was unprecedented in Canadian electric power system history. The Ontario Hydro Report provides a chronology of the twenty-three major storms that have impacted the system since 1942. The report also provides a detailed inventory of the effects, consequences, and mitigation measures taken due to the ice storm. The estimated direct total cost to Ontario due to the ice storm is 472 inillioii (Canadian), which includes costs incurred by Ontario I lydro, local Ontario and federal governments, the Insurance Bureau of Canada and associated insurance companies, the Department of National Defence, and affected customers, incliidiiig... 

Control Systems, History of Anibal T. De Almeida Hashem Akbari... 

Weisgerber DW. Chemical Abstracts Service Chemical Registry System history, scope, and impacts. J Am Soc Inf Sci 1997 48 349-60. 

Mason, B. and Moore, C.B. (1982). Principles of Geochemistry (4th ed.). Wiley, New York Press, F.S. and Siever, R. (1986). Earth (4th ed.). W.H. Freeman and Company, New York Stanley, S.M. (2002). Earth System History. W.H. Freeman and Company, New York Wayne, R.P. (2002). Chemistry of Atmospheres (3rd ed.). Oxford University Press, Oxford Williams, R. J.P. and Frausto da Silva, J.J.R. (1996). The Natural Selection of the Chemical Elements - The Environment and Life s Chemistry. Clarendon Press, Oxford... 

Stanley, S.M. (2002). Earth System History (3rd printing). W.H. Freeman and Company, New York Thompson, D.W. (1961). On Growth and Form (abridged edition) J.T. Bonner (ed.) Cambridge University Press, Cambridge (reprinted 1988)... 

Geiss, J. Gloeckler, G. 2003, in R. Kallenbach et al. (eds.), Solar System History from Isotopic Signatures of Volatile Elements, Dordrecht Kluwer, = Space Sci. Rev., 106, 3. 

Rolfs CE, Rodney WS (1988) Cauldrons in the cosmos. University of Chicago Press, Chicago Rotaru M, Birck JL, Allegre CJ (1992) Clues to early solar system history from chromium isotopes in carbonaceous chondrites. Nature 358 465-470... 

Wasson JT (1985) Meteorites Their Record of Early Solar System History. New York Ereeman Wesolowski DJ, Benezeth P, Palmer DA (1998) ZnO solubility and Zrf+ complexation by chloride and sulfate in acidic solutions to 290°C with in-situ pH measurement. Geochim Cosmochim Acta 62 971-984 Wessel P, Smith WHF (1991) Free software helps map and display data. EOS Trans AGU 72 445-446 Xiao Z, Gammons CH, Williams-Jones AE (1998) Experimental study of copper(I) chloride complexing in hydrothermal solutions at 40 to 300°C and saturated water vapor pressure. Geochim Cosmochim Acta 62 2949-2964... 

This isotope is particularly significant, as it is thought to have been a potent source of heating for asteroids and planets early in solar system history. A variety of other shortlived isotopes have now been confirmed in meteorites and are the basis for high-resolution chronometry of the early solar system. 

One drawback of the Pb-Pb system is that two-stage or three-stage evolution of the U-Pb isotopic system can produce linear arrays on a Pb-Pb isochron plot (Gale and Mussett, 1973). If these arrays are interpreted as single-stage isochrons, incorrect dates may be obtained. In some cases, measurements of the U/Pb ratio can help identify multistage samples. But if several events occurred sufficiently early in solar system history, even a concordia approach may not be able to identify a multistage system (Tera and Carlson,... 

Overall, the 26Al-26Mg system is relatively sensitive to thermal resetting. The half-life of 730 000 years means that the 26Al-26Mg system is suitable for dating events during the first 5 Myr of solar system history. 

The tools that we have to determine the age of the solar system and the chronology of early solar system materials are the long-lived and short-lived radiochronometers discussed in Chapter 8. The long-lived radionuclides tell us that the oldest objects in the solar system formed at -4.5-4.6 Ga (Fig. 9.8). But the precision of most of these measurements is not sufficient to investigate the details of those early times. In addition, there are uncertainties in the half-lives of the different radionuclides that translate into absolute uncertainties of several million to tens of millions of years. Short-lived radionuclides provide the time resolution necessary to unravel the details of early solar system history. 

A peak in the shock ages for HED meteorites also corresponds to the period of late heavy bombardment on the Moon. This is unlikely to be a coincidence, and provides further support for this important event in solar system history. 

An explanation of how radioactive isotopes are used to quantify solar system history... 

Consequently, for a system that is in operational use and does not meet the criteria for retrospective validation, the approach should be to establish documented evidence that the system does what it purports to do. To do this, an initial assessment is required to determine the extent of documented records that exist. Existing documents should be collected, formally reviewed, and kept in a system history file for reference and to establish the baseline for the validation exercise. From the document gap analysis the level of redocumenting and retesting that is necessary can be identified and planned. 

Description of process/environment Quality-related critical parameters Purpose and objectives of the system Major benefits of the system Special requirements Specific training needs System operating strategy Related GMP compliance/regulations Physical and logical boundaries System GMP risk assessment System validation rationale Life-cycle documentation Assumptions and prerequisites Limitations and exclusions Quality-related critical parameters/data Standard operating procedures System requirement specification Supplier and system history... 

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