Abstract. We present a novel microscopic model of sorption and convection of ions in heterogeneous media. Our model is based on an analogy to electron transport in a semiconductor. A new feature of our model is a power law random distribution of the adsorption time of ions. Diverging standard deviation of the distribution function yields anomalous ion transport. We show that this anomalous transport explains a concentration profile with a long tail that has been observed in column experiments. We successfully fit recent experimental data. Finally, we propose new experiments by which we can check the validity of our model. IntroductionThere have been many column experiments on reactive flow in heterogeneous media. Complete understanding of these local-scale experiments is important for understanding fieldscale heterogeneity. However, previous theoretical models for column experiments have produced only limited success. In the present paper we propose a novel model with heterogeneity of a new type and thereby explain the results of recent column experiments which were carefully performed with superior precision. Nakayama et al. In the present paper we propose a novel microscopic model of sorption and convection of nuclides. The theoretical solution of our model agrees with the experimental results of JAERI very well, particularly with the long tail of the concentration profile. Our theory also predicts that concentration profiles with different water flow rates should be identical to each other when we rescale the profiles. This theoretical prediction is also realized in the JAERI experimental data. We thereby conclude that our new model captures an essential feature of sorption and convection in heterogeneous media.We assume heterogeneity of ion adsorption in our model. A new feature is a random distribution function of adsorption time with diverging standard deviation, as opposed to the randomness with finite deviation assumed in previous studies on heterogeneous media. There have been theoretical studies 1027

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We have found that the room-temperature ionic liquid (RTIL) reveals outstanding pressure-induced phase changes from a liquid state to a crystal polymorph and finally to a glass form upon compression by up to 8 GPa. The RTIL is 1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim][PF6], which offers the opportunity to investigate a variety of fluctuations in one system and can be completely recovered without dissociation or polymerization, even after decompression. Similar to charge frustration, spin ice-like frustration, and geometric frustration in high potential spintronics/multiferroic materials, the RTIL frustrations are classified into charge (scalar), orientation (vector), and coordination number (topology). Degrees of freedom at each state of [C4mim][PF6] are described by charge balancing, molecular orientational order/disorder, molecular conformations of the C4mim(+) cation, and the coordination number. Here, we show a novel "conformation glass" induced by high pressure.

We have investigated the effect of deuterated water on the conformational equilibrium between the gauche and trans conformers of the [bmim] cation in mixtures of water and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF(4)]), an ionic liquid, at room temperature. A comparison of the results obtained from solutions made with H(2)O and with D(2)O highlights an anomalous conformational change in the D(2)O solution showing an extended N-shaped behavior. The gauche conformer of the [bmim] cation in D(2)O increased up to x = ~50 (D(2)O mol %); however, it decreased up to higher water concentrations of x = ~85 before again increasing drastically toward x = ~100. We provide spectroscopic evidence that the anomalous conformational dynamics of the [bmim] cation in D(2)O is directly related to the H/D exchange reaction of the C-H group at position 2 of the imidazolium ring.