Collective effect

Our studies of the absorption, permeation, and extraction properties of containers produced from high nitrile barrier resins have demonstrated that they meet or surpass the basic criteria established for retention of taste and odor characteristics of carbonated soft drinks. Sensory tests, which can isolate and identify end results as well as integrate collective effects, have confirmed this judgement and have established the general compatibility of these containers with a variety of beverage products from a taste and odor standpoint. Furthermore, these materials have the excellent physical properties required for containers which will find wide use in food and beverage packaging. 

The hypothesis proposed in [76] implies that collective effects change the collisional event statistics in a hard sphere liquid. The collisional distribution tp(t) dt is assumed to deviate from the famous Poissonian law i/>(t) = exp (—t/To)/r0 corresponding to the flow of events being uniform in time. The distribution... 

Dispersive forces are more difficult to describe. Although electric in nature, they result from charge fluctuations rather than permanent electrical charges on the molecule. Examples of purely dispersive interactions are the molecular forces that exist between saturated aliphatic hydrocarbon molecules. Saturated aliphatic hydrocarbons are not ionic, have no permanent dipoles and are not polarizable. Yet molecular forces between hydrocarbons are strong and consequently, n-heptane is not a gas, but a liquid that boils at 100°C. This is a result of the collective effect of all the dispersive interactions that hold the molecules together as a liquid. 

The pressures exerted by gases demonstrate molecular motion. Gases are collections of molecules, so the pressure exerted by a gas must come from these molecules. Just as the basketball In Figure 2J exerts a force when it collides with a backboard, moving gas molecules exert forces when they collide with the walls of their container. The collective effect of many molecular collisions generates pressure. 

STAACK R, KINGSTON s, WALLiG M A and JEFFERY E H (1998) A Comparison of the individual and collective effects of four glucosinolate breakdown products from Brussels sprouts on induction of detoxification enzymes , Toxicol Appl Pharmacol, 149 17-23. 

Instead, we believe the electronic structure changes are a collective effect of several distinct processes. For example, at surfaces the loss of the bulk symmetry will induce electronic states with different DOS compared to bulk. As the particle sizes are decreased, the contribution of these surface related states becomes more prominent. On the other hand, the decrease of the coordination number is expected to diminish the d-d and s-d hybridization and the crystal field splitting, therefore leading to narrowing of the valence d-band. At the same time, bond length contraction (i.e. a kind of reconstruction ), which was observed in small particles [89-92], should increase the overlap of the d-orbitals of the neighboring atoms, partially restoring the width of the d-band. 

MPC dynamics follows the motions of all of the reacting species and their interactions with the catalytic spheres therefore collective effects are naturally incorporated in the dynamics. The results of MPC dynamics simulations of the volume fraction dependence of the rate constant are shown in Fig. 19 [17]. The MPC simulation results confirm the existence of a 4> 2 dependence on the volume fraction for small volume fractions. For larger volume fractions the results deviate from the predictions of Eq. (92) and the rate constant depends strongly on the volume fraction. An expression for rate constant that includes higher-order corrections has been derived [95], The dashed line in Fig. 19 is the value of /. / ( < )j given by this higher-order approximation and this formula describes the departure from the cf)1/2 behavior that is seen in Fig. 19. The deviation from the <[)11/2 form occurs at smaller values than indicated by the simulation results and is not quantitatively accurate. The MPC results are difficult to obtain by other means. 

Exploration of collective effects in multiple transfers that appear when the donor and acceptor are the same molecules and display the so-called homotransfer. In this case, the presence of only one molecular quencher can quench fluorescence of the whole ensemble of emitters coupled by homotransfer [32]. The other possibility of using homo-FRET is the detection of intermolecular interactions by the decrease of anisotropy [33]. 

The general or universal effects in intermolecular interactions are determined by the electronic polarizability of solvent (refraction index n0) and the molecular polarity (which results from the reorientation of solvent dipoles in solution) described by dielectric constant z. These parameters describe collective effects in solvate s shell. In contrast, specific interactions are produced by one or few neighboring molecules, and are determined by the specific chemical properties of both the solute and the solvent. Specific effects can be due to hydrogen bonding, preferential solvation, acid-base chemistry, or charge transfer interactions. 

Potentiometric titrations yield more precise results than direct measurements, better than 0.2% if required. This is because the data collected effectively averages Ecell over a large number of readings. The principal types of potentiometric titration are summarized in the following sections. 

Having now found the classical electrophoretic term from a microscopic analysis of the system ions plus solvent, we should analyze more complicated diagrams in order to see whether there is any other contribution than (468) in the limiting form of the electrophoretic term. Indeed, it is very tempting to develop an analysis similar to the one followed in the study of the relaxation term and to consider the possibility of more complicated collective effects. These would have essentially three origins ... 

Marck N. H., Parrinello M. Collective Effects in Solids and Liquids II Adam Hilder Ltd, Bristol, 1982. 

Demchenko AP (2010) Collective effects influencing fluorescence emission. In Demchenko AP (ed) Advanced fluorescence reporters in chemistry and biology. II. Springer Ser Fluoresc 9 107-132... 

Collective Effects Observed with Organic Dyes. 116... 

Realization of Collective Effects in Sensing and Imaging Technologies. 124... 

Collective effects in multiple transfers can be seen when the donor and acceptor are the same molecules and display the so-called homo-transfer. The homo-transfer is reversible, so the excitation energy can travel within the ensemble of closely located dyes until the act of emission. Commonly, since the dyes are oriented randomly in space, the emission of such an ensemble becomes totally depolarized. This case is depicted in Fig. 4a. 

The collective effects of directed energy flow can be strongly enhanced when the dyes playing the role of donors and acceptors are different and optimally selected. The hetero-FRET (described in Sect. 3.2) occurring within an ensemble of dissimilar molecules allows many possibilities for this. The transfer and the quenching... 

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