Dill model

Figure 4 A cross-sectional schematic of the Dill model for the micelle. Counterions are not shown. (From Ref. 2 with permission.)...

The notion that folding proceeds from a condensed state rather than from a random coil state is somewhat heretical in an age dominated by the secondary structure nucleation point of view. However, the question has not been addressed experimentally, and the Dill model is in accord with the thermodynamics of unfolding for many globular proteins. 

When it was observed that the DNQ/novolac resists in use at the time became more transparent on exposure (i.e., they bleached). Dill used this change in optical absorbance as a way of monitoring the kinetics of exposure. He developed a first-order model of exposure consisting of three parameters A, B, and C, now called the Dill model, which accurately fit the experimental measurement results of the transmittance of a resist coating on an optically matched glass wafer as a function of exposure dose. The Dill parameters A, B, and C, describe bleachable absorbance, nonbleachable absorbance, and exposure rate constant, respectively." ... 

Figure 12.6 Comparison of the accuracy of the Dill model, Mack model, and enhanced (advanced) Mack model in modeling the dissolution rate data of AZ 7908 resist developed in 300-MIF developer. (Courtesy of R. Dammel.)...

Dill K A, Bromberg S, Yue K, Fiebig K M, Yee D P, Thomas P D and Chan H S 1995 Principles of protein folding—a perspective from simple exact models Protein Sci. 561-602... 

KA Dill, S Bromberg, K Yue, KM Fiebig, DP Yee, PD Thomas, HS Chan. Principles of protein folding—A perspective from simple exact models. Protein Sci 4 561-602, 1995. 

The Henry s law constant value of 2.Ox 10 atm-m /mol at 20°C suggests that trichloroethylene partitions rapidly to the atmosphere from surface water. The major route of removal of trichloroethylene from water is volatilization (EPA 1985c). Laboratory studies have demonstrated that trichloroethylene volatilizes rapidly from water (Chodola et al. 1989 Dilling 1977 Okouchi 1986 Roberts and Dandliker 1983). Dilling et al. (1975) reported the experimental half-life with respect to volatilization of 1 mg/L trichloroethylene from water to be an average of 21 minutes at approximately 25 °C in an open container. Although volatilization is rapid, actual volatilization rates are dependent upon temperature, water movement and depth, associated air movement, and other factors. A mathematical model based on Pick s diffusion law has been developed to describe trichloroethylene volatilization from quiescent water, and the rate constant was found to be inversely proportional to the square of the water depth (Peng et al. 1994). 

Because simple lattice models take no account of local directional preferences, they fail to model these important local restraints on protein structure. Instead, they rely almost entirely on long-range interactions to encode the most stable conformation(s) (Dill et al., 1995). Thus the ability of lattice models to reproduce protein-like behavior must be called into question. And though their simplicity makes them intellectually attractive, their use in teaching and modeling protein-like behavior must be qualified with a caveat that local directional preferences have been ignored. 

In the model of micelle proposed by Dill et al. [21], the hydrocarbon chains of the surfactants are more randomly distributed, bearing in mind statistical considerations (Fig. 4). A considerable number of hydrocarbon chains are exposed to the water at the surface. 

The models of Fromherz and Dill allow the solubilization of hydrophobic solutes near the surface of the micelle and explain how these solutes (in addition to part of the hydrocarbon chains of the surfactants) can be in contact with the water when they are associated with the micelle. However, the debate concerning the structure of the clusters is not yet finished and research on the subject continues. 

A very popular scheduling framework is based on mixed-integer programming. Herein, the scheduling problem is modeled in terms of variables and algebraic inequalities and solved by mathematical optimization techniques. In opposition to this well-established framework, a different approach is advocated in the paper by Alur and Dill [8] on timed automata (TA). 

Hexachloroethane released to water or soil may volatilize into air or adsorb onto soil and sediments. Volatilization appears to be the major removal mechanism for hexachloroethane in surface waters (Howard 1989). The volatilization rate from aquatic systems depends on specific conditions, including adsorption to sediments, temperature, agitation, and air flow rate. Volatilization is expected to be rapid from turbulent shallow water, with a half-life of about 70 hours in a 2 m deep water body (Spanggord et al. 1985). A volatilization half-life of 15 hours for hexachloroethane in a model river 1 m deep, flowing 1 m/sec with a wind speed of 3 m/sec was calculated (Howard 1989). Measured half-lives of 40.7 and 45 minutes for hexachloroethane volatilization from dilute solutions at 25 C in a beaker 6.5 cm deep, stirred at 200 rpm, were reported (Dilling 1977 Dilling et al. 1975). Removal of 90% of the hexachloroethane required more than 120 minutes (Dilling et al. 1975). The relationship of these laboratory data to volatilization rates from natural waters is not clear (Callahan et al. 1979). 

The dominant fate process for chloroform in surface waters is volatilization. Chloroform present in surface water is expected to volatilize rapidly to the atmosphere. An experimental half-disappearance range of 18-25 minutes has been measured for volatilization of chloroform from a 1 ppm solution with a depth of 6.5 cm that was stirred with a shallow pitch propeller at 200 rpm at 25 °C under still air ( 0.2 mph air currents) (Dilling 1977 Dilling et al. 1975). Using the Henry s law constant, a half-life of 3.5 hours was calculated for volatilization from a model river 1 meter deep flowing at 1 meter/second, with a wind velocity of 3 m/second, and neglecting adsorption to sediment (Lyman et al. 1982). A half-life of 44 hours was estimated for volatilization from a model pond using EXAMS (1988). 

Environmental Fate. Experimental data are available regarding the transport and partitioning properties of chloroform in surface waters (Bean et al. 1985 Clark et al. 1982 Class and Ballschmidter 1986 Dilling 1977 Ferrario et al. 1985 Piwoni et al. 1986 Sawhney 1989). Chloroform partitions mainly into the atmosphere and into groundwater. Empirical measurements or model predictions on half-disappearance times in such media as soil could not be identified in the literature. Chloroform can be transported long distances in air. Data are available regarding the degradation of chloroform in the... 

Chodera, J.D., Singhal, N., Pande, V.S., Dill, K.A., Swope, W.C. Automatic discovery of metastable states for the construction of Markov models of macromolecular conformational dynamics. J. Chem. Phys. 2007, 126, 155101-17. 

Oil-water partitioning, solubilities, and vapor-pressure experiments on smaU-molecule compounds are often used as models to obtain energies for biomolecular modeling. For example, measured partition coefficients, K, are often inserted into the formula-RT In K to obtain quantities thought to represent microscopic contact interaction free energies (Chan and Dill, 1997). 

Pierce, C.H., Dills, R.L., Morgan. M.S.. Nothstein, G.L., Shen, D.S. Kalman, D.A. (1996) Interindividual differences in 2Hg-toluene toxicokinetics assessed by a semiempirical physiologically based model. Toxicol, appl. Pharmacol., 139, 49-61... 

By AEDA the four odorants shown in Figure 9 were detected with the highest FD-factors in dill herb [33], A mixture of these compounds, dissolved in water at the same concentration ratios occurring in the herb (Table 16) very much resembled the typical odor of the dill herb. If (S)-a-phellandrene or the dill ether (B and A Fig. 9), respectively, were omitted, the mixture lost its typical odor note. On the contrary, omission of myristicin and methyl 3-methylbutanoate (D and C Fig. 9) did not significantly influence the overall dill herb aroma of the model mixture [33, 66], The data indicated that (S)-a-phellandrene and the dill ether are the character impact compounds of the dill herb. Since, on the basis of AEDA or calculation of OAVs further odorants have been shown to contribute to the dill herb flavor [33, 66], the results of the simulation experiments revealed that obviously the two monoterpenes are able to mask the flavor contributions of these compounds. 

Model solution simulating the flavor of dill herb [331... 

Tmskett and Dill (2002) proposed a two-dimensional water-like model to interpret the thermodynamics of supercooled water. This model is consistent with model (1) for liquid water. Cage-like and dense fluid configurations correspond to transient structured and unstructured regions, observed in molecular simulations of water (Errington and Debenedetti, 2001). Truskett and Dill s model provides a microscopic theory for the global phase behavior of water, which predicts the liquid-phase anomalies and expansion upon freezing. 

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