Molecular history

Benner S. A., Caraco M. D., Thomson J. M., and Gaucher E. A. (2002) Evolution—Planetary biology—Paleontological, geological, and molecular histories of life. Science 296(5569), 864-868. 

Monte Carlo Simulation of Individual Molecular Histories... 

When simulating the molecular histories, especially for the experiments with shortlived nuclides, it is necessary to note that the actual processing time is a random variable with an individual value for each molecule. It is so not only because of the individual lifetimes of the involved nuclei, but also due to some external factors. These are, for example, the nominal t c and the temporal profile of injection. However, equally important is the temporal regime of detection of the decay events — whether they are registered in the course of the run or after its end. 

Most of the results mentioned below come from Ref. [22], where 5,000 molecular histories were followed to obtain each zone profile. The experimental conditions and properties of the processed species were broadly varied. Listed in that paper are various characteristics of the sampled zones zui and TK, z. and 7a, coordinate and temperature of the zone maximum, as well as variance, skewness and kurtosis excess... 

Scherer J J, Paul J B, O Keefe A and Saykally R J 1997 Cavity ringdown laser absorption spectroscopy history, development, and application to pulsed molecular beams Chem. Rev. 97 25-51... 

The next step towards increasing the accuracy in estimating molecular properties is to use different contributions for atoms in different hybridi2ation states. This simple extension is sufficient to reproduce mean molecular polarizabilities to within 1-3 % of the experimental value. The estimation of mean molecular polarizabilities from atomic refractions has a long history, dating back to around 1911 [7], Miller and Sav-chik were the first to propose a method that considered atom hybridization in which each atom is characterized by its state of atomic hybridization [8]. They derived a formula for calculating these contributions on the basis of a theoretical interpretation of variational perturbation results and on the basis of molecular orbital theory. 

History and Objectives of Quantitative Drug Design. In Hansch C, P G Sammes and J B lor (Editors) Comprehensive Medicinal Chemistry Volume 4. Oxford, Pergamon Press, pp. 1-31. emd H van de 1995. Chemometric Methods in Molecular Design. Weinheim, VCH Publishers. 

In studying molecular orbital theory, it is difficult to avoid the question of how real orbitals are. Are they mere mathematical abstractions The question of reality in quantum mechanics has a long and contentious history that we shall not pretend to settle here but Koopmans s theorem and photoelectron spectra must certainly be taken into account by anyone who does. 

You can detect hydroxyl group transitions by plotting dihedral angles versus time over the course of the simulation. This is the distance history. Brady investigated the distance history of water 19. Brady, J.W. Molecular dynamics simulations of a-d-glucose in aqueous solution. 

Monte Carlo (MC) techniques for molecular simulations have a long and rich history, and have been used to a great extent in studying the chemical physics of polymers. The majority of molecular modeling studies today do not involve the use of MC methods however, the sampling capabiUty provided by MC methods has gained some popularity among computational chemists as a result of various studies (95—97). Relevant concepts of MC are summarized herein. 

Activated carbons contain chemisorbed oxygen in varying amounts unless special cate is taken to eliminate it. Desired adsorption properties often depend upon the amount and type of chemisorbed oxygen species on the surface. Therefore, the adsorption properties of an activated carbon adsorbent depend on its prior temperature and oxygen-exposure history. In contrast, molecular sieve 2eohtes and other oxide adsorbents are not affected by oxidi2ing or reducing conditions. 

Some representative backbone stmctures of PQs and PPQs and their T data are given in Table 1. As in other amorphous polymers, the Ts of PQs and PPQs are controlled essentially by the chemical stmcture, molecular weight, and thermal history. Several synthetic routes have been investigated to increase the T and also to improve the processibiUty of PPQ (71). Some properties of PPQ based on 2,3-di(3,4-diaminophenyl)quinoxaline and those of l,l-dichloro-2,2-bis(3,4-diaminophenyl)ethylene are summarized in Table 2. 

NIDDM is a much more common disease than IDDM, accounting for about 85—90% of all cases of diabetes meUitus. Whereas NIDDM may be present at any age, the incidence increases dramatically with advanced age over 10% of the population reaching 70 years of age has NIDDM. Patients with NIDDM do not require insulin treatment to maintain life or prevent the spontaneous occurrence of diabetic ketoacidosis. Therefore, NIDDM is frequendy asymptomatic and unrecognized, and diagnosis requires screening for elevations in blood or urinary sugar. Most forms of NIDDM are associated with a family history of the disease, and NIDDM is commonly associated with and exacerbated by obesity. The causes of NIDDM are not well understood and there may be many molecular defects which lead to NIDDM. 

The use of PC—ABS blends has grown significantly in the early 1990s. These blends exhibit excellent properties, particularly low temperature ductihty, reduced notch sensitivity, and ease of melt fabrication. The blend morphology (229), ABS composition, thermal history (215), PC content and molecular weight (300), processing conditions, etc, all affect the mechanical behavior of PC—ABS blends. These blends have been most frequently used in automotive and other engineering appHcations. 

The PVA price has historically reflected the cost of ethylene, acetic acid, and energy. The price history for a medium molecular weight, fully hydrolyzed grade is 0.77/kgin 1970, 2.20/kgin 1980, 2.75/kgin 1988, and 2.65/kgin 1995. 

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