SYNOPSISA dielectric relaxation peak due to bound water of globule proteins in aqueous solution was observed at first by the use of a time domain reflectometry. This peak locates around 100 MHz as well as that of the aqueous DNA solution and the moist collagen, and has a relaxation strength in proportion to surface of the globule protein except for trypsin and pepsin of hydrolase. It is suggested that this peak is caused by orientation of bound water molecules on the protein surface. The number of bound water molecules estimated is in good agreement with that obtained by other method such as x-ray analysis. The solution exhibits another peak below 100 MHz, which is caused by the rotation of globule protein supplemented by migration of the counterion. Its relaxation time is completely proportional to the molecular weight of the protein. I NTRO DUCT10 NGlobule protein is one of the most important materials in biology. It has a lot of biological functions in living materials. For example, the enzyme works as a catalyst of hydrolysis, oxidation and reduction. In the living materials the protein molecules are surrounded by water in most cases. Therefore it is of particular interest to investigate the water structure around the protein.High resolution x-ray and neutron diffraction measurements in the crystal phase have made clear that there are peculiar water molecules correlating strongly with the globule protein.' It is suggested that the water molecules attach to the oxygen, nitrogen, and polar groups on the globule protein surface through hydrogen bonding. This bound water is thought to give an important influence on the functions of protein. In the case of trypsin of hydrolase, such water molecules construct a network with polar groups, which maintains the shape of active site, and stabilizes the protein structure. Existence of this water is also ascertained by a computer simulation employing molecular dynamic^.^,^ On the other hand, the sorption measurement of water vapor indicated that there are often a number of sorption points on the globule protein that is estimated, from a relationship between the vapor pressure and the amount of ~o r p t i o n .~The numbers of sorption point of albumin, cytochrome C and lysozyme obtained are 241, 56, and 60, respectively, which are roughly equal to those of polar residues per protein molecule, which are 375,65, and 80, re~pectively.~ It has been thus suggested that the sorption water is bound to the polar group^.^ However, most of the functions of globule protein does not appear in the crystal phases, where the protein structure is stabilized by the intermolecular interaction and the large structural fluctuation is restricted. Then water in the crystal phase seems to be different from that in vivo. Therefore it is again interesting to know the structure of bound water in aqueous solution.Recently dielectric measurement by using a time domain reflectometry (TDR) method have been performed on the DNA aqueous solution5 and the moist collagen.6 Two relaxation peaks were observ...

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On a macroscale, the effect of installing prefabricated vertical drains (PVDs) in a subsoil is to increase the mass hydraulic conductivity of the subsoil in the vertical direction. Based on this concept, a simple method for modeling PVD improved subsoils is proposed, in which an equivalent vertical hydraulic conductivity k v e for the PVD improved subsoil is explicitly derived. With the proposed simple method, analysis of PVD improved subsoil is the same as that of the unimproved case. The theoretical verification of the simple method was made under 1D condition. The calculated average degree of consolidation and excess pore pressure distribution in the vertical direction using the simple method are compared with existing theoretical solutions (combination of Terzaghi's consolidation theory and Hansbo's solution for PVD consolidation). It has been proved theoretically that, in terms of average degree of consolidation, in the case of one layer and ignoring the vertical drainage of natural subsoil, the maximum error of the proposed method is 10% compared with Hansbo's solution. For the case of one layer or multilayers and considering both vertical and radial drainages with the parameters adopted here, the maximum error of the proposed method is 5%. The multilayer case was analyzed by FEM method, and the proposed simple method is compared with that of using 1D drainage elements. Then, 2D finiteelement analyses were conducted for three case histories of embankments on PVD improved subsoils. One case is discussed in detail. The analyses using both the simple method and 1D drainage elements, were conducted. It is shown that for all three cases, the simple method yielded results as good as those using 1D drainage elements.

A method for predicting the traffic-load-induced settlement of road on soft subsoil with a low embankment is proposed. The traffic-load-induced dynamic stress in subsoil is calculated by the multilayer elastic theory ͑not covered in this paper͒. Then the plastic vertical strain in subsoil is calculated by an empirical equation, in which constants are related to the physical and mechanical properties of subsoil. The method was applied to analyze three different cases in Saga, Japan. Comparisons of the calculated values with field data indicate that the proposed method can provide a reasonable prediction of traffic-load-induced permanent settlement of the road on soft subsoil with a low embankment. The method is useful for designing the road with a low embankment on soft subsoil. For the cases studied with embankment thickness of 0.75 to 2.7 m, the depth significantly influenced by traffic load is about 6 m below the base of the embankments.

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Complex formation between a carboxyl-terminated cascade polymer (generation 3) and several cationic polyelectrolytes of varying linear charge density was studied as a function of ionic strength, by turbidimetric titration and dynamic light scattering. Tetramethylammonium chloride was used to adjust the ionic strength in order to avoid sodium counterion binding to dendrimer carboxyl groups. Complex formation occurred abruptly at a critical pH, as signaled by a sudden change in either the turbidity or the apparent Stokes radius from dynamic light scattering. The pHc of incipient complex formation was converted to the critical surface charge density σc. Under conditions of low or moderate ionic strength (I), it was confirmed that σc is roughly proportional to κ/ξ, where κ ∼ I 1/2 is the Debye−Hückel parameter and ξ is the linear charge density of the polyelectrolyte.

Dielectric measurements were performed on water–p-dioxane and methanol–p-dioxane mixtures using time domain reflectometry over the frequency range 0.1–10 GHz. In the case of water–p-dioxane mixtures, the relaxation strength normalized by the number of water molecules per unit volume is independent of the molar fraction of water xW if xW<0.83. There are no ordered micellelike clusters in the mixture. On the other hand, if xW is larger than 0.83, the normalized strength increases linearly with xW. The clusters of pure water which appear in this region are cyclic and consist of six molecules. In the case of methanol–p-dioxane, the normalized strength is independent of xM for xM<0.66 and increases linearly with xM for xM>0.66. However, the relaxation time of pure methanol is too large for clusters consisting of three molecules. It is suggested that the chainlike clusters form network structures.

Dielectric relaxation measurements over an extremely wide frequency region from 1 MHz to 20 GHz were performed on water mixtures with glucose, polysaccharides, and L-xylo ascorbic acid by the use of time domain refiectometry. For mixtures of polysaccharides bigger than maltotriose, two relaxation peaks were definitely observed. The high frequency relaxation is the water relaxation and the low frequency one is due to orientation of polysaccharide molecules. In the case of glucose, only one relaxation peak could be observed. It is shown that a hexagonal cluster in the lattice of ice can be replaced easily by the glucose molecule, where the lattice is distorted slightly, but stabilized by several hydrogen bonds between the glucose molecule and the lattice. Although the cluster can be replaced by the L-ascorbic acid molecule too, the lattice cannot be kept stable. Its water mixture shows two relaxation peaks clearly. It is suggested that water has a structure of the distorted lattice of ice. Fluctuation of the lattice breaks the hydrogen bonds and the lattice is decomposed. Orientation of the water molecules released gives rise to the relaxation concerned.