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The bonding character of liquid lead telluride \text{PbTe} is thermodynamically investigated in detail. Its possibility as an ionic melt composed of cation {\text{Pb}}^{2+} and anion {\text{Te}}^{2-} is not acceptable, by comparing the ionization energy of \text{Pb} atom, electron affinity of \text{Te} atom and the ionic bonding energy due to the cation {\text{Pb}}^{2+} and anion {\text{Te}}^{2-} with the help of structural information. Solid lead telluride PbTe as a narrow band gap semiconductor might yield easily the overlapping of the tail of valence band and that of conduction one. And on melting, it becomes to an ill-conditioned metallic state, which concept is supported by the electrical behaviors of liquid Pb–Te alloys observed by the present authors. As structural information tells us about the partial remain of some sorts of covalent-type mono-dipole and poly-dipole of the molecule \text{PbTe}, all systems are thermodynamically explained in terms of a mixture of these molecules and cations {\text{Pb}}^{4+} and {\text{Te}}^{2+} and a small amount of the conduction electrons are set free from these elements based on the ternary solution model.

The former analysis of the structural data in liquid Pb–Te alloys, based on the neutron diffraction measurements for this system, was insufficient to obtain the microscopic and spatial configurations in this system. In order to obtain these configurations, we have newly analyzed by using the Reverse Monte Carlo simulations and the method of Voronoi polyhedron. The partial structure factors {S}_{ij}(Q) and thereby {g}_{ij}(r) are newly estimated by using the former data of neutron diffraction measurements, which are now exactly reproduced by the obtained total structure factors S(Q). From these results, it is concluded that the liquid Pb0.5Te0.5 is spatially configured by the mixture of some sorts of covalent-type formation of PbTe molecules and dissociated Pb and/or Te ions with conduction electrons, which result is completely consistent with results of electrical resistivity measurements and also with the thermodynamic analysis.

Ray-summation (raysum) images reconstructed from computed tomography (CT) volume data resemble digital radiography (DR) images. Therefore, they have a potential to be used instead of DR images.The aim of this study was to compare the physical image quality evaluated by signal-difference-to-noise ratio (SDNR) and clinical usefulness between raysum and DR images. We employed an oval water phantom simulating adult abdomen for image quality measurement. Raysum images were reconstructed from CT volume data using an assumed x-ray quality of 70 keV. DR images were obtained using an indirect-type flat panel detector system. The normalized noise-power spectrum (NNPS) for various same dose indices (DR: entrance surface dose, CT: CT dose index volume) were measured from raysum and DR images. SDNRs were calculated from the results of NNPSs, modulation transfer function (MTF), and cartilage material contrast. Five experienced observers visually compared each pair of a clinical raysum image and a DR image for nine clinical cases (head, finger, pelvis, and foot). MTF of raysum was significantly lower than that of DR. SDNRs of DR were superior to those of raysum for each dose index, by an average factor of 1.24. For head and pelvis images, raysum images were comparable or a little superior compared with the DR images, because the radiation doses of raysum was much higher than those of DR. For finger and foot cases, the raysum images were inferior to DR images due to its lower resolution. Our results indicated a limited clinical usefulness of raysum compared with DR.

The electrical conductivity in aqueous solutions of electrolytes has been obtained in terms of inter-particle potentials and pair distribution functions, based on a generalized Langevin equation for the cation and anion. This treatment allows us to connect and compare with the work of a computer simulation where the inter-particle potentials are the only input. The results for the concentration dependence of electrical conductivity are basically represented as a function of the square root of concentration. The electrophoretic and relaxation effects are discussed from a microscopic view point. The ionic hydration in electrolytic solution is also discussed. Available inter-particle potentials in aqueous solutions of electrolytes are proposed. The numerical application is carried out for sodium chloride and other aqueous electrolyte solutions.

A microscopic description for the partial DC conductivities in molten salts developed by the present authors is briefly summarised, starting from the Langevin equation for the constituent ions. It is clarified that the memory function should be written as the form of , in which is the Fourier–Laplace transform in the long wavelength limit and the integration from zero to infinity for being unity. To solve the mutual relation between the combined velocity correlation functions to elucidate the DC conductivities and the memory function of the Langevin equation in a short time region, we propose a new recursion method. Practical application is carried out for the derivation of the fitted memory function from the of molten NaCl obtained by MD simulation. This fitted function in the short time region is approximated to a summation of three kinds of the Gaussian functions, and their physical interpretations are discussed.

The theory of the pre-melting phenomena in ionic crystals on the basis of the concept of the hetero phase fluctuation has been applied to KCl and AgCl crystal. The large scale molecular dynamics simulations (MD) in KCl and AgCl crystals are also performed to examine the ionic configuration in pre-melting region in the vicinity of their melting points. The size of the liquid like clusters are estimated by the theory and MD. The structural features of liquid like clusters are discussed by MD results using the Lindemann instability condition. The ionic conductivities in the pre-melting region are also discussed on the same theoretical basis.

The inverse dielectric function 1/ɛ(q) is newly obtained in terms of the charge–charge correlation functions SZZ(q) by the re-examined theory of dielectric screening in molten salts. The new theory is applied to the molten noble-metal halides, i.e. AgBr and CuBr, in order to obtain SZZ(q), and in due course, 1/ɛ(q). The inter-ionic screened potential ϕ sc + − ( r ) is estimated using 1/ɛ(q). The obtained screened potential ϕ sc + − ( r ) is treated as the potential of mean force to obtain the partial pair distribution function between cation and anion g+−(r). The results are compared to those obtained by diffraction experiments and molecular dynamics simulation. The deviation from Nernst–Einstein relation in the transport properties is also discussed.

The electrical conductivity of non-equivalent molten salts has been theoretically investigated based on the linear response theory, which is an extension from the expression for equivalent molten salts as we have developed in the previous papers. The velocity correlation functions are expressed in terms of pair potentials and pair distribution functions. Using these functions and Langevin equations for ions, the relations among the conductivity coefficients are obtained. It is shown that the ratio of partial conductivities σ+/σ− is equal to |z +|m − /|z − |m +, which is an extensive expression from the inverse mass ratio in the case of equivalent molten salts. Numerical results for molten CaCl2 and AlF3 are presented, which agree well with the results of experiments and molecular dynamics simulations.

Regarding the ionic conductivities, Sundheim proposed the “universal golden rule” by experiments, i.e. the ratio of the partial ionic conductivities in molten binary salt is equal to the inverse mass ratio of the ions, σ + / σ − = m − / m + . In previous work, we have proved this relation by molecular dynamics simulations (MD) and a theory using the Langevin equation. In this study, the pseudo-binary molten salt system (AgI) 1− c (AgBr) c is investigated in the same theoretical framework. MD results are also reported in connection with the theoretical analysis.

The screened effect in molten AgI–AgBr system is discussed by the inverse dielectric function 1/ϵ(q), which is newly obtained in terms of the charge–charge structure factor S ZZ (q) by the re-examined theory of dielectric screening in molten salts. S ZZ (q) and in due course, 1/ϵ(q) are obtained from structural properties of molten AgI–AgBr system by molecular dynamics (MD) simulations. The obtained 1/ϵ(q) is multiplied onto the attractive part in the inter-ionic potential between cation and anion to obtain the screened potential. The total screened potential is examined in terms of the potential of mean force.

The diffusion constants of both cation and anion in liquid Cu 2 Se have been measured based on the time dependence of decaying residual potential due to the charge polarization after the turning-off of applied current. The experimental decaying curves were fitted by three exponential terms. Two terms correspond to the diffusion process of copper and selenium ions, respectively, and the rest is attributed to a relaxation of electronic polarization. It is found that the temperature dependences of diffusion constants of copper and selenium ions are negligibly small, on the other hand, the relaxation time of electronic polarization increases with increasing temperature.

Background The usefulness of ultrasound-guided needle aspiration for subpleural lesions has been reported. However, no reports have evaluated its usefulness and safety in patients with respiratory comorbidities such as chronic obstructive pulmonary disease (COPD) and interstitial pneumonia (IP), which can increase the risk of iatrogenic pneumothorax. In this study, we evaluated the influence of chronic respiratory diseases (CRDs) on the usefulness and safety of ultrasound-guided needle aspiration for subpleural lesions. Methods Between January 2000 and September 2011, we examined 144 patients with intrapulmonary subpleural lesions. We retrospectively reviewed clinical data, including lesion size on thoracic computed tomography (CT), ultrasound findings, pathological findings obtained by ultrasound-guided needle aspiration, final diagnosis, and complications. Results A positive definitive diagnosis was obtained in 74.3% of all 144 patients; 84.7% patients with malignant diseases, including lung cancer; and 26.9% patients with benign diseases. Of the 144 patients, 64 belonged to the CRD group and 80 to the non-CRD group. The former included 31 patients with COPD, six with emphysematous changes on thoracic CT, 17 with IP, and 10 with other diseases. The positive rate of diagnosis for malignant diseases was 84.7% in the CRD group, which was the same as that in the non-CRD group. With regard to complications related to ultrasound-guided aspiration, there were only two cases of pneumothorax in the CRD group and one in the non-CRD group. Conclusion Ultrasound-guided aspiration is safe and useful for subpleural lesions, particularly malignant lesions, even in patients with respiratory comorbidities such as COPD and IP.

We have carried out the molecular dynamics simulation for molten Li 2 CO 3 -K 2 CO 3 mixtures. The structural feature was revealed from the obtained radial distribution function and angular distribution function. The dynamic properties such as diffusion constant and the electrical conductivity were also derived. The nonequilibrium molecular dynamics was performed to calculate the electrical conductivity. The relation of the concentration dependence of dynamical properties and structural change was discussed.

The time-of-flight neutron scattering measurements have been carried out for liquid Sn–Se system. A distinct change in structural properties has been observed between Sn 70 Se 30 and Sn 60 Se 40 , ...

The magnetic susceptibility of liquid Ag–As 2 Se 3 system have been analyzed under the assumption that the paramagnetic susceptibility is attributable to the formation of dangling bonds. The diamagnetic susceptibility due to the ion core have been estimated in order to discuss the bonding nature and suggests that liquid Ag–As 2 Se 3 system has a strong covalent bonding nature in As 2 Se 3 -rich region. The activation energy and the entropy of the formation of dangling bonds have also been estimated and these value decreases with increasing the concentration of Ag. These results are attributable to the destruction of As–Se network structure by the addition of Ag and the covalent bonding nature of overall network is gradually changed with composition.

The structure factor of liquid Zn has newly been obtained by neutron diffraction above melting temperature with sufficient accuracy by a powder diffractometer with multi-detector system, HERMES, which is installed at T1-3 beam line in JRR-3M. The observed structure factor of liquid Zn has a very clear profile in the low Q region less than Q=4.5 A−1 and connected with the structural data obtained previously. The structure factor of liquid Zn by X-ray diffraction has an asymmetric peak profile, while that by neutron diffraction does not. There has been detected a small but clear difference around the first peak region. Electron-ion correlation function and electron charge distribution around an ion have been obtained. The relation between the liquid structure and the electron charge distribution around an ion for liquid Zn will be discussed as compared with the simple liquid metals.

The molecular dynamics calculations are carried out for molten NaCl and AgI. The radial distribution function and their configurational fluctuation are calculated and the difference between the fluctuation of NaCl and that of AgI is confirmed. The electrical conductivities are also obtained by using the non-equilibrium molecular dynamics method, and these results agree with the experimental conductivities. Furthermore, the deviation from the Nernst–Einstein relation is derived and the relation of the structural fluctuation and the deviation is discussed.

The measurements of electronic and ionic conductions in liquid In–Se and Cu–Se systems have been carried out separately as a function of concentration and temperature. The electronic conductivities of these systems have minima near the composition x=0.58 for the In1−xSex system and x=0.33 for the Cu1−xSex system. Both systems have maxima in the ionic conductivities at the same composition. In proportion as the electronic conductivity increases with changing composition, the ionic conductivity decreases. In Se-rich region of Cu–Se system, the change from negative to positive temperature dependence of the electronic conductivity and a discontinuous change in the ionic conductivity have been observed at a certain temperature.

The magnetic susceptibility of molten Ag(Cl1−xIx) was measured as a function of temperature below the liquidus temperature and up to 1050°C. The diamagnetic susceptibility of AgCl increases with increasing temperature after melting, while the susceptibility of molten AgI does not change on melting and its value decreases only slightly with increasing temperature in the liquid state. The temperature coefficients of the susceptibilities in AgCl rich region are rather larger than those in AgI rich region. The susceptibility isotherm of molten Ag(Cl1−xIx) at 700°C is almost linear with composition in each AgCl or AgI rich region. However, there appears a discontinuity in the linear relation around equi-molar fraction. We suggest that there is a difference of the bonding between AgCl and AgI rich region.

Faber-Ziman type partial structure factors in liquid Na-Pb alloys have been derived by using the so-called concentration independent method from the observed total structure factors. A ternary hard-sphere mixture model composed of atoms Na and Pb and Na4Pb molecule is applied to this system. It is shown that the estimated partial structure factors under the assumption of the mixture of hard spheres are in good agreement with the observed ones.

Electrical conductivities and thermoelectric powers have been measured as a function of temperature and composition in AgI–AgBr system. The electronic conductivities in its superionic phase are negligibly small in comparison with ionic conductivities. The composition dependence of activation energies slightly decreases with increasing the bromine concentration. The lattice constant in this phase decreases with increasing the bromine concentration. The reduction of bottle neck size in conducting path of mobile ion, which originated from the decreasing of the lattice constant, produces the enhancement of activation energy. But this prediction is contradicted with the present observations. These behaviors may be attributable to a distortion of crystal lattice. The heat of transport obtained from measurements of thermoelectric power is slightly larger than the activation energy of ionic conduction in the superionic phase. This relation may be qualitatively explained by the model of Fokker–Plank equation.

Based on the Langevin equations for cations and anions in a molten salt, the ionic partial conductivities are discussed in connection with their masses. These partial conductivities are shown in terms of current-current correlation functions as an extension of Kubo theory. And these partial conductivities are also described in terms of conductivity tensors which are introduced from the macroscopic irreversible thermodynamic viewpoint. These theoretical results are justified by the molecular dynamics simulations carried out for molten NaCl and NaI.

A new promise method to derive experimentally the diffusion constants of cation and anion in molten salts, which is based on the time-dependent decaying of the charge polarization in them, has been presented. The application was carried for molten AgI. The determined diffusion constants of cation and anion are reasonably agreed in comparison with the results by computer simulation. AC conductivity in molten salts is theoretically discussed in terms of a simplified Langevin equation and an application is also carried out for molten AgI. From these, the average value of the deviation from the Nernst-Einstein relation weighing by the diffusion constants of cation and anion is obtained as a function of temperature, indicating a large amount of collective motion of the same kinds of ions under the external field.

A phenomenological theory is given for the time dependence of the relaxation process of an α-AgI sample which has been previously polarized by the application of a voltage. The electromotive force caused by the internal electric field due to the polarized charge distribution is given by a series of exponential terms as a function of Dt, with D being the effective diffusion constant and t the time. The diffusion constants are obtained at several temperatures. In addition, the AC conductivity was measured for the same specimen. The results are analyzed with the help of a generalized Drude theory. Using both the results of the diffusion constant D and the AC conductivity, deviations from the Nernst-Einstein's relation are derived. Furthermore, computer simulations on these quantities were carried out by using well-established pairwise potentials. The agreement is satisfactory.

江戸川区では公費乳癌一次検診に全例超音波検査 (以下, US) による画像診断を視触診と併用して行っている。施設検診における江戸川区公費乳癌検診の7年間の成績をもとに, 乳癌一次検診におけるUSの有用性について検討した。対象は江戸川区在住の30歳以上の女性約16万人のうち平成2年4月～平成9年3月に受診した延べ36,972例である。検診は視触診とUS, 乳頭異常分泌のある受診者には細胞診検査を行った。視触診は, 当医師会の会員医師が当番制で行い, USは, 日本超音波医学会認定の超音波検査士6名で行った。発見乳癌190例, 早期乳癌103例, 乳癌発見率0.51%, 早期乳癌比率54.2%, sensitivity90.5%, 早期非触知乳癌率38.8%であった。年代別では, 40歳代が発見乳癌 (39.5% : 75/190), 早期乳癌 (40.8% : 42/103) ともに最も多かった。USを用いた乳癌検診は乳癌発見率, 早期乳癌比率, sensitivity, 早期非触知乳癌率が全国平均と比較して高く, 特に40歳代を中心とした若年層に重点をおいた乳癌検診に有用であった。

The magnetic susceptibility of the liquid In 1- x Se x system have been measured as functions of concentration and temperature. The magnetic susceptibility of the system shows a broad diamagnetic maximum near x =0.58. This behaviour corresponds to the concentration variation of electronic conductivity reported previously and supports our previous suggestion of the valence fluctuation of In ions. By using the data of magnetic susceptibility with known electronic conductivity and thermoelectric power data, the density of state N ( E ) have been determined and the diamagnetic susceptibility due to ion core, χ d , has also been obtained. The obtained value of χ d suggests the occurrence of monovalent In ion near the composition x =0.58.

With the progress of solid state physics for this quarter century, a number of interesting behaviours in liquids, especially, liquid metals and alloys, liquid semiconductors and compound-forming liquid alloys have experimentally and theoretically been investigated. Above all, the phase transition in liquid Se-Te alloys is one of most important and instinctive phenomena concerned with their structural, thermodynamic and electronic properties, because it appears with increasing temperature only. Recent progress on this interesting phenomenon has been reviewed in detail. Another interesting phenomenon in liquid matters is the so-called p-n transition, which is, more or less, similar to the case of solid semiconductors. Most p-n transitions in polyvalent-chalcogen alloys have been explained in terms of their thermodynamic, structural and electronic points. In addition, phase separations in liquid alloys and liquid mixtures of organic compounds including water are also discussed in terms of concentrat...

Electronic and ionic conductivities and thermoelectric power of liquid In 1- x –Se x system have been measured as a function of concentration and temperature. The electronic conductivity in the system shows a deep minimum near the Se composition x =0.58 and the ionic conductivity has a broad maximum at this composition, where the thermoelectric power shows a large negative maximum. The electronic conductivity and thermoelectric power were analyzed in terms of the Fermi-Dirac integrals. It is found that the shape of the density of state, N ( E ), changes gradually with concentration.

Thermodynamic stability, taking account of the electronic and ionic structures in liquid Ag–polyvalent metal alloys, has been discussed in comparison to other monovalent–polyvalent metal alloys. Liquid Ag–Zn, Ag–Ga, Ag–In and Ag–Sn alloys show some ordered states as seen in their S CC (0), and have different electronic and ionic structures in Ag- and polyvalent metal-rich regions, respectively. S CC (0) of liquid Ag–Pb and Ag–Tl alloys has shown the tendency to phase separation.

The partial structure factors of molten copper haildes (CuCl, CuBr and CuI) have been derived from the observed total structure factors by means of the Reverse Monte Carlo simulation technique. The static dielectric functions are also obtained using these partial structure factors and it is found that these experimental dielectric functions satisfy either the inequality form e(q)e1 or e(q) < 0.

江戸川区では30歳以上の女性を対象に, 公費無料乳癌一次検診として超音波検査士によるリアルタイム方式の超音波検査 (以下, US) を全例に施行している。最近5年間の成績をもとにして40歳代を中心に検討した。5年間の総受診者は26,042名で, 40歳代では8,988名 (34.5%) であった。乳癌は144名で乳癌発見率0.55%であった。その内訳は30歳代8名 (5.6%), 40歳代61名 (42.4%), 50歳代40名 (27.8%), 60歳代29名 (20.1%), 70歳以上6名 (4.2%) で, 40歳代がもっとも多かった。40歳代の乳癌発見率は0.68%の高い検出率で, 早期乳癌率は59.0%であった。乳癌が増加傾向にある現状においては若年層の早期乳癌を発見することが重要である。USは受診者に苦痛を与えることもなく, また装置の簡便性から普及率も高く, 超音波検査士も年々増加してきた。これらの状況から, 40歳代の乳癌一次検診には高い検出率を示すUSを年に1度超音波検査士が施行することがきわめて有用であると考えられた。

The total structure factors, S(q), of liquid Ag-In alloys have been derived by X-ray diffraction measurements. The concentration dependence of the first peak position is divided into three groups; on going from Ag to 70 at% Ag, the peak position decreases linearly and it goes to decrease with a more rapid proportion for the concentration range from 70 to 40 at% Ag, and furthermore it becomes nearly constant for the remained concentration range. In order to know the information of a local configuration for this system, the partial structure factors are derived from the obtained total structure factors by assuming that they are independent for a concentration range. And they agree with the results obtained by the reverse Monte Carlo simulation method. From these partial structural information, we propose that the partial structure factors in Ag rich side are different from those in In rich side.

By using well-established pairwise potentials in which a partially covalent bonding character is taken into account, detailed structural properties and the diffusion constants for molten CuCl, CuBr, and CuI have been simulated. The results obtained from the velocity correlation function method and those obtained from the mean square displacement one agree well. The activation energies for cations and anions are discussed in connection with the local ionic configuration. The shear viscosities for these molten salts at various temperatures are also estimated by using a nonequilibrium molecular dynamics simulation. The results for CuCl are fair to good in comparison with experimental data.

By using well-known pairwise potentials, the transport coefficients such as diffusion constant, viscosities and electrical conductivities in molten NaCl have been simulated as a function of temperature. In deriving the conductivity, a nonequilibrium molecular dynamics technique has newly applied and obtained results at several temperatures agree quantitatively with the experimental results. Using the simulated diffusion constants, D + and D - , and the partial electrical conductivities σ + and σ - , deviations from the Nernst-Einstein relation, for positive and negative ions Δ + and Δ - , at several temperatures are also estimated. The average values for Δ + and Δ - are the order of 0.1 and comparable to the experimental result.

An attempt has been made to describe the effective pair potentials for a binary fluid mixture using the Percus-Yevick and Hypernetted Chain equations with the partial structural functions; pair distribution functions and structure factors. A new method has also been proposed for estimating the effective pair potentials in a binary fluid with a long-range Coulombic interaction coupled with measured structural data. The basic idea with the modified Hypernetted Chain equation was taken from a predictor-corrector method originally proposed by Reatto et al. in 1986 for a single component fluid. The capability of this new method was tested by estimating the effective pair potentials of molten NaCl, considering one of the typical ionic liquids. The usefulness of this method was demonstrated by obtaining the effective pair potentials of molten CuBr showing a particular structureless behavior in the Cu-Cu correlation.

The electrical conductivity and the transference number of silver-dissolved α-CuI in the superionic phase were measured as a function of temperature and composition. It was recognized that both Ag and Cu ions could be mobile and the activation energy for Ag ions is smaller than that for Cu ions. It is emphasized that the size of the Ag ion is more suitable for conduction than that of the Cu ion in this phase. Since the ionic radius for the Ag ion is larger than that of the Cu ion, we propose a model other than the gate model to explain this experimental fact.

Powder X-ray diffraction measurements for Ag + doped α-CuI system in its superionic phase have been carried out. The most probable crystal structure seems to be an anti-fluorite one in which a part of cations are occupied at octahedral sites. The occupation probability of cation at the octahedral site rapidly increases with increasing Ag ion concentration. This result is qualitatively consistent with that obtained from the ionic conductivity measurements.

Based on the experimental results of magnetic susceptibilities for liquid silver-polyvalent metals systems, the dielectric behaviours and thereafter the charge distributions in these systems have been derived. Concentration dependence of a compound forming effect for the charge distribution in liquid Ag–In and Ag–Sn alloys has been found to be an anomalous, while such dependence can be scarcely found in liquid Ag–Pb alloys.

X-ray diffraction experiments for stage-2 potassium-intercalated graphite C 24 K and stage-1 C 8 K have been carried out. Disordered profiles have been observed for both samples. The measured structure factor S(Q) for the disordered potassium in C 8 K shows a characteristic subpeak in the small angle region below the first peak, which suggests that there exists a short-range order in the potassium layers. The phases of the pair distribution function g(r) and S(Q) for the potassium layers in C 8 K disagree with those in C 24 K. To check the influence of the carbon layers, the profiles of g(r) s of C 8 K and C 24 K are compared with that of normal liquid potassium.

Copyright (c) 1996 Elsevier Science B.V. All rights reserved. The viscosity of liquid Na and Fe was estimated by using a non-equilibrium molecular dynamics simulation. The effective pair potential used for Na, which is based on the pseudopotential method, reproduces excellently the temperature dependence of viscosity in liquid Na. For Fe, an experimentally determined pair potential from the Born−Green equation and effective pair potentials based on the hybridized expression of a nearly free electron tight-binding method were used. These potentials were used to calculate the temperature dependence of viscosities of liquid Fe. The results obtained are fair to good, qualitatively and semiquantitatively. For comparison, g(rrs based on the usual molecular dynamics simulation for these liquid metals were also calculated, and the results were satisfactory.

The estimation of viscosity of liquid sodium and iron by using nonequilibrium molecular dynamics simulation was carried out. The used effective pair potential based on pseudopotential method reproduces excellently the temperature dependence of viscosity of liquid sodium. By using the experimentally determined pair potential from Born-Green equation and the effective pair potentials based on the hybridized expression of a nearly free electron and tight binding method, the temperature dependence of viscosities of liquid iron have been obtained. The obtained results are fair to good, qualitatively and semiquantitatively. For reference, g(r)'s and self diffusion constants based on the usual molecular dynamics simulation for these liquid metals were also performed and the results were satisfactory.

Neutron and X-ray diffraction measurements were carried out for molten V 2 O 5 to determine the detailed atomic structure. The observed pair distribution function by neutron diffraction expresses the oxygen pairs, and there exist oxygen atoms located at a distance of 2.76 A around a central oxygen atom. The atomic coordinations of V-V and V-O have also been evaluated from both structure factors. An atomic configuration of this molten salt is supported by the tetrahedrally coordinated one, and some of these are connected by the three corners of four. The ultrasonic velocity and sound absorption measurements were also carried out to investigate the dynamical properties. The sound absorption for this molten salt decreases with increasing temperature, while the ultrasonic velocity is about 950 m/s above melting temperature and almost constant with increasing temperature. The structure and dynamical properties of such clustered liquid are discussed in relation to the network structure.

An investigation based on the results of the magnetic susceptibility and structural properties for liquid Ag-polyvalent metal alloys has been carried out. Magnetic susceptibilities of liquid Ag-In, -Sn, -Ga, and -Zn systems have been measured over a temperature range from 600 to 1085 °C. The concentration dependences of the electron susceptibility ( χ electron ) for these four alloys show a characteristic behavior in the Ag-rich region. The concentration dependences of d χelectron /dT as a function of the number of electrons per atom have a similar feature, qualitatively. The results of resistivity measurements are also discussed.

Neutron diffraction studies of liquid Ge-Se and Ge-Te mixtures have been carried out by using the steady-state and pulsed neutron sources. The structure factors for liquid Ge 33 Se 67 suggest that Ge and Se atoms form covalent bonds in the liquid state and that a network structure is formed. However, this structure is quickly broken with increasing temperature or by changing the composition of mixtures. On the other hand, the bonds between Ge and Te atoms seem to be weaker than those between Ge and Se atoms and show metallic properties.

EXAFS measurements at the Ag and I K-absorption edges have been carried out for molten AgBr-AgI mixtures near the melting temperatures to obtain the information on partial structures. The results obtained from a curve fit analysis show that with increasing AgI concentration, Ag-Br and Ag-I interionic distances become slightly short, which may suggest the enhancement of covalent character. The partial structures are discussed from a view point of a cluster formation suggested from the results of neutron diffraction measurements.

The structure factors of liquid Na, Mg and Al have been obtained by neutron diffraction above each melting temperature with sufficient accuracy and compared with the structural data obtained by X-ray diffraction. Neutrons, being scattered by nuclei, determine the ionic structure factor, while X-ray scattering is related to the correlation among electrons. There has been detected a small but clear difference larger than the experimental uncertainties between these two structure factors. The systematic difference of the screening charge around an ion will be discussed for these liquids.

The specific heat for AgI-doped CuI has been measured by the method of differential scanning calorimetry. Anomalous specific heats were observed around the transition temperature from non-superionic to superionic phases. These were well explained in terms of the Schottky-type excess specific heat.

Total electrical conductivities and transference numbers of the Ag x Cu 1− x in the α-phase were measured as a function of temperature and composition. In this phase, it has been recognized that both Ag and Cu ions could be mobile and, in addition, the activation energies for both mobile ions are nearly the same. A structure refinement for this phase shows that both Ag and Cu ions vibrate at the 12d site with a large anharmonicity. However, the lattice constant obeys Vegard's law. This result indicates that both mobile ions have the same conducting path although their amplitudes of anharmonic thermal vibrations are different.