Molecular perspective

KM Merz Jr, B Roux, eds. Biological Membranes A Molecular Perspective from Computation and Experiment. Boston Birkhauser, 1996. 

B Roux, TB Woolf. Molecular dynamics of Pfl coat protein in a phospholipid bilayer. In KM Merz Ir, B Roux, eds. Biological Membranes A Molecular Perspective from Computation and Experiment. Boston Birkhauser, 1996, pp 555-587. 

Philipson KD, Nicoll DA (2000) Sodium-calcium exchange a molecular perspective. Annu Rev Physiol 62 111-133... 

Count the atoms of each element to be sure that the reaction is balanced and reasonable from a molecular perspective. 

A molecular perspective reveals why energy must be supplied to boil water. A molecule of water cannot escape the liquid phase unless it has enough energy of motion to overcome the hydrogen bonding forces that hold liquid water together. About 40 kJ of heat must be supplied to transfer 1 mol of water molecules from the liquid phase into the vapor phase. 

The story of the ozone hole illustrates how important it is to learn the molecular details of chemical reactions. Some chemists use information about how reactions occur to design and synthesize useful new compounds. Others explore how to modify reaction conditions to minimize the cost of producing industrial chemicals. This chapter explores how chemical reactions occur at the molecular level. We show how to describe a reaction from the molecular perspective, introduce the basic principles that govern these processes, and describe some experimental methods used to study chemical reactions. 

To obtain a molecular perspective of reaction rates, consider the unimolecular reaction shown in Figure 15-3. At elevated temperature, the compound ds-2-butene can rearrange to form its isomer, trans-2-butene. The reaction occurs after collisions transfer enough energy to a ds-2-butene molecule to break the C — C jrbond. Once the bond breaks, rotation around the C — C a bond takes place rapidly until a jrbond forms again. 

Figure 16-1 depicts these two processes from the molecular perspective. 

From a molecular perspective, just as I2 and I" can combine to form I3, it is reasonable that trllodlde can break apart into the substances from which it originally formed. 

If the pressure of CO2 in the furnace were to reach 1.0 bar, the system would attain equilibrium, and no additional products would form. If the CO2 is allowed to escape from the reactor as it forms, on the other hand, the continuous removal of CO2 drives the reaction to completion. Figure 16-7 illustrates this from a molecular perspective. Continuous removal of a product maintains the pressure of CO2 below 1.0 bar, so Q has a smaller value than. S eq, and the reaction continues until all the CaC03 has been converted to CaO. 

Analyze the problem from the molecular perspective. Begin by identifying the major species present. Then identify the equilibria in which these ions participate. 

Gillespie, S.H. (1993) The clinical spectrum of human toxocariasis. In Lewis, J.W. and Maizels, R.M. (eds) Toxocara and Toxocariasis Clinical, Epidemiological and Molecular Perspectives. Institute of Biology, London, pp. 55-61. 

Gillespie SH Evolution of drug resistance in Mycobacterium tuberculosis Clinical and molecular perspective. Antimicrob Agents Chemother 2002 46 267-274. 

Quingley CA, DeBellis A, Marschke KB, El-Awady MK, Wilson EM, French FS (1995) Androgen receptor defects historical, clinical and molecular perspectives. Endocr Rev 16 271... 

Lonard DM, Smith CL (2002) Molecular perspectives on selective estrogen receptor modulators (SERMs) progress in understanding their tissue-specific agonist and antagonist actions. Steroids 67 15-24... 

Jentsch TJ (1996) Chloride channels a molecular perspective. Curr Opin Neurobiol 6 303-310... 

Miyoshi J and Takai Y [2005] Molecular perspective on tight-junction assembly and epithelial polarity. Adv Drug Deliv Rev 57 815-855... 

Drewes LR (1999) What is the blood brain barrier A molecular perspective. Adv Exp Med Biol 474 1147-1152... 

Wang JC (2002) Cellular roles of DNA topoisomerases a molecular perspective. Nat Rev Mol Cell Biol 3 430-440... 

Schlenkrich, M., Brickmann, J., MacKerell Jr., A. D., and Karplus, M. (1996) An empirical potential energy function for phospholipids criteria for parameter optimization and application. In Biological membranes a molecular perspective from computational and experiment, Merz Jr., K. M. and Roux, B. (eds.), Birkhauser, Boston, 31-81. 

Schacter DL (1987) Implicit memory history and cmrent status. J Exp Psychol 13 501-518 Schafe GE, LeDoux JE (2000) Memory consolidation of auditory Pavlovian fear conditioning requires protein synthesis and protein kinase A in the amygdala. J Neurosci 20 RC96 Schafe GE, Nader K, Blair HT, LeDoux JE (2001) Memory consolidation of Pavlovian fear conditioning a cellular and molecular perspective. Trends Neurosci 24 540-546... 

Schafe GE, Nader K, Blair HT, LeDoux JE (2001) Memory consolidation of Pavlovian fear conditioning a ceUiflar and molecular perspective. Trends Neurosci 24 540-546... 

As physical chemists, our goal is to describe and predict chemical properties of real substances from a molecular perspective. How are pressure and volume related for argon gas, for instance The straightforward way to describe argon is to perform experiments in which the pressure is varied and record the volumes that result, leading to the inverse relationship originally observed by Boyle. 

Throughout this chapter we have dealt with surface tension from a phenomenological point of view almost exclusively. From fundamental perspective, however, descriptions from a molecular perspective are often more illuminating than descriptions of phenomena alone. In condensed phases, in which interactions involve many molecules, rigorous derivations based on the cumulative behavior of individual molecules are extremely difficult. We shall not attempt to review any of the efforts directed along these lines for surface tension. Instead, we consider the various types of intermolecular forces that exist and interpret 7 for any interface as the summation of contributions arising from the various types of interactions that operate in the materials forming the interface. 

When we view these processes from a molecular perspective, we see that melting and freezing occur simultaneously, as Figure 8.6 illustrates. 

Closely related to the use of models is the corresponding one of stereoviews to illustrate molecular perspective. The increased availability of molecular data and the use of computers to generate stereoviews has made their use routine in journal accounts of structure determinations. Unlike models, no matter how useful, stereo-views have the ability to capture the depth of a three-dimensional structure on a two-dimensional sheet of paper. An increased number of stereoviews has been included in this edition. 

Rimbach G, Boesch-Saadatmandi C, Frank J, Fuchs D, Wenzel U, Daniel H, Hall W, Weinberg P. 2008. Dietary isoflavones in the prevention of cardiovascular disease—A molecular perspective. Food Chem Toxicol 46 1308-1319. 

Jordan BR. 1996. The effects of ultraviolet-B radiation on plants A molecular perspective. Adv Bot Res 22 97-162. 

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