Middle science

I suspect that the status of chemistry as the middle science makes it especially fertile ground for the development of hybrid representation schemes that function explicitly as inferential tools. Consider, for example, chemical equations, Lewis structures, the periodic table, and reaction mechanism diagrams. In each case there is a rich story of novel representation in the face of complexity. We would do well to consider in a more systematic manner how such representation schemes can be robust inferential tools, how issues of representation are related to explanatory power, and how recognition of amalgamated concepts might influence our accounts of reduction and intertheoretic relations more generally. 

Gold [7440-57-5] Au, is presumably the first metal known and used by humans. It occurs ia nature as a highly pure metal and is treasured because of its color, its extraordinary ductility, and its resistance to corrosion. Early uses ia medicine and dentistry date to the ancient Chinese and Egyptians. In the Middle Ages the demand for gold led to the iatense, unsuccesshil efforts of alchemists to convert base metals iato gold. These pursuits became the basis for chemical science. The search for gold has been an important factor ia world exploration and the development of world trade. 

FIG. 16-2 Limiting fixed-bed behavior simple wave for unfavorable isotherm (top), square-root spreading for linear isotherm (middle), and constant pattern for favorable isotherm (bottom). [From LeVan in Rodtigues et al. (eds.), Adsorption Science and Technology, Kluwer Academic Publishers, Dotdtecht, The Nethedands, 1989 reptinted withpeimission.]... 

Serious science started in Russian empire in the middle of the XVIII century. The first known Russian scientist M.V. Lomonosov obtained (in the I750sJ experimental data on the preservation of the mass of substances in chemical reactions. T.E. Lovits discovered adsorption from solutions he used wood carbon as an adsorbent. Among other scientists, Lovits detected compounds using characteristic forms of their crystals. V.M. Severgin published a book on analysis of mineral raw materials. 

Figure 12.9 Schematic diagram of the stmc-ture of a potassium channel viewed perpendicular to the plane of the membrane. The molecule is tetrameric with a hole in the middle that forms the ion pore (purple). Each subunit forms two transmembrane helices, the inner and the outer helix. The pore heJix and loop regions build up the ion pore in combination with the inner helix. (Adapted from S.A. Doyle et al., Science 280 69-77, 1998.)...

Figure 12.11 Schematic diagram of the ion pore of the K+ channel. From the cytosolic side the pore begins as a water-filled channel that opens up into a water-filled cavity near the middle of the membrane. A narrow passage, the selectivity filter, links this cavity to the external solution. Three potassium ions (purple spheres) bind in the pore. The pore helices (red) are oriented such that their carboxyl end (with a negative dipole moment) is oriented towards the center of the cavity to provide a compensating dipole charge to the K ions. (Adapted from D.A. Doyle et al.. Science 280 69-77, 1998.)...

Figure 14.2 Models of a collagen-like peptide with a mutation Gly to Ala in the middle of the peptide (orange). Each polypeptide chain is folded into a polyproline type II helix and three chains form a superhelix similar to part of the collagen molecule. The alanine side chain is accommodated inside the superhelix causing a slight change in the twist of the individual chains, (a) Space-filling model, (b) Ribbon diagram. Compare with Figure 14.1c for the change caused by the alanine substitution. (Adapted from J. Bella et al.. Science 266 75-81, 1994.)...

Rapid advances in understanding the nature and behaviour of materials required both kinds of skill, in measurement and in theory, acting in synergy among metallurgists, this only came to be recognised fully around the middle of the twentieth century, at about the same time as materials science became established as a new discipline. 

Consider the examples of some of the forms of chemical equations (and related representations) met in school and college (i.e. middle and senior high school) science and chemistiy classes that are shown in Table 4.1. For the purposes of this chapter half-equations (Example 11) and symbolic representations of processes such as ionisation (Example 10) will be included under the generic heading of chemical equations . Table 4.1 does not include examples of chemical reactions and reaction schemes that include stmctural formulae, as are commonly nsed in organic chemistiy. 

Grosslight, E., Unger, C., Jay, E., Smith, C. E. (1991). Understanding models and their use in science conceptions of middle and high school students and experts. Journal of Research in Science Teaching, 28(9), 799-822. 

Lee, O., Eichinger, D. C., Anderson, C. W., Berkheime, G. D. (1993). Changing middle school student s conceptions of matter and molecules. Journal of Research in Science Teaching, 30, 249-270. 

Nakhleh, M.B., Samarapungavan, A. Saglam, Y. (2005). Middle school students belief about matter. Journal of Research in Science Teaching, 42(5), 581-612. 

Monaghan Slotta (2001) notice that despite the amount of literature on the understanding of students preconceptions as well as on the pedagogy for assisting students conceptual change, the majority of middle school and high school science... 

Novak, A. M., Gleason, C. I. (2000). Incorporating portable technology to enhance an inquiry, project-based middle school science classroom. In R. T. Tinker J. S. Krajeik (Eds.), Portable technologies science learning in context (pp. 29-62). Dordrecht Kluwer. 

Butzer, K.W, Beaumont, PB. and Vogel, J.C. 1978 Lithostratigraphy of Border Cave a Middle Stone Age sequence heginning at c. 195,000 YTP. Journal of Archaeological Science 5 317-341. 

Fig. 8.36 Leyt Spectrum of the soil close to the crater rim where Opportunity entered and exited the crater. The basaltic soil is unusually high in hematite (but no indication of significant contribution Irom hematitic spherules). Middle rover tracks. Right 750 m diameter (. 75 m deep) eroded impact crater Victoria Crater, formed in sulfate-rich sedimentary rocks. Image acquired by the Mars Reconnaissance Orbiter High-Resolution Science Experiment camera (Hirise). The red line is the drive path of Opportunity exploring the crater. (Courtesy NASA, JPL, ASU, Cornell University)...

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