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An inhomogeneous structure model is applied to liquid Ga2Te3 to account for the dependence of its physical properties. The electronic properties are analysed in terms of an effective-medium percolation theory with the volume fraction of the metallic domains determined from Knight shift data. The temperature dependence of the molar volume and the total structure factor can be explained consistently within the same framework. The results indicate that liquid Ga2Te3 consists of two kinds of domains, non-metallic and metallic, with different structures. As in the case of In2Te3 the former has a structure similar to the defect zincblende structure of the solid. From analysis of the pair distribution function for the metallic domain, it is inferred that the dissociation process Ga2Te3 to 2GaTe+Te occurs. Valence fluctuations of the metallic elements are proposed to interpret the temperature and composition dependence of the physical properties of liquid IIIb (Al, Ga, In, Tl)-Te systems. The well known plot of nuclear spin relaxation against conductivity by Warren (1971) should be reinterpreted.

The composition dependence of the change in the hard-sphere diameters component metal, due to the charge transfer on alloying, is obtained from the entropy and from the structure factor data on the basis of the hard-sphere model. The results obtained in these two different ways agree well with each other and are consistent with the result of the first principles calculation and with the result deduced from the electronegativity.

New measurements of the free energy and entropy of mixing and the associated thermodynamic properties of liquid Na-Cd and Na-In alloys are reported. It is inferred that there exists some kind of short-range order of Na, whilst there is a phase separation tendency in the alloys in the Na-rich region. These contradictory features are interpreted in terms of the interchange energies in the alloys which vary as a function of Na concentration.

The velocity of sound wave propagation and attenuation have been measured in molten AgX (X=Cl, Br and I) at temperatures beginning from the respective melting points to about 850°C. The observed sound velocities decrease almost linearly with increasing temperature, and sound attenuation in molten AgI is larger than that in molten AgBr and AgCl. The adiabatic compressibility is derived from the sound velocity; in these molten salts, the adiabatic compressibilities are discussed from the viewpoint of the mixed characteristics of covalent and ionic one. The isothermal compressibility of liquid AgI was calculated by using the three partial distribution functions which were already calculated by the hypernetted chain approximation using the pair potentials. The calculated result is comparable to the experimental one.

A detailed analysis of X-ray scattering intensity of liquid Ni–25, 50 and 75 at. % Si alloys has been carried out by X-ray diffraction with anomalous scattering technique. The scattering powers of these alloys were changed by the anomalous scattering by the Ni atom of Mo, Cu and Co radiations and the three partial structure factors required to characterize a binary alloy were estimated. It is found that they are approximately independent of the concentration of the alloys and the Ni and Si atoms act to a first approximation as hard spheres in liquid Ni–Si alloys.

A detailed analysis of the X-ray scattering intensity of alpha -AgI has been carried out by an anomalous scattering technique. The two partial interference functions Sijdif(Q) for Ag-Ag and Ag-I pairs were estimated using the newly developed theoretical equations of the intensity. The partial distribution functions for I-I, Ag-I and Ag-Ag pairs in this work are consistent with the results obtained from molecular dynamics by Vashishta and Rahman (1978). The intensities of Debye lines were also explained satisfactorily in terms of pair distribution function for Ag-I pairs.

The neutron diffraction study of liquid tellurium has been carried out to reveal the origin of characteristic temperature dependence of various properties related to the atomic scale structure. The temperature dependence of measured structural functions of liquid tellurium could be explained by a gradual transition from the two-fold coordinated ordering (non-metallic) to the three-fold coordinated one (metallic). Thermodynamic properties of liquid tellurium have also been appeared to be consistent with the present interpretation for the change in structure with increasing temperature.

The ordering process of FeNi 3 alloy from its disordered state was detected by means of resistivity as a function of annealing temperature. The phase stability of the ordered state was examined by thermal analysis and its structure was also observed by X-ray diffraction. From these measurements, four processes toward the ordering were recognized, which depended on both annealing temperature and annealing time. Physical properties such as the ordered cluster size and the activation energy were evaluated, and the mechanism of ordering process was discussed.

The thermodynamic quantities of mixing such as free energy ΔG, entropy ΔS and enthalpy ΔH of liquid Na-IVb alloys are discussed in view of formation of chemical complex. From these, the excess specific heat ΔC p as a function of temperature, which is resulted from the dissociation of chemical complex, is particularly concerned. The discrepancies in the compound-forming tendencies among liquid NaPb, NaSn and LiPb are also discussed.

The phase diagram and the heat of transition of AgI-AgBr system have been determined by using the differential scanning calorimetry (DSC) with the help of X-ray diffraction patterns. It has been verified that the miscibility gap between β-AgI-type solid solution and AgBr-type one depends on the thermal history of the sample. From the thermodynamic point of view, it is likely that the variation of transition temperature with composition suggests the change of correlation among silver ions in superionic conducting phase.

The calculations of specific heats of (Ag x Cu 1- x )Br were compared with experimental data taken from the literature. The negative temperature coefficients of specific heat (d C p /d T

New measurements of the free energy and entropy of mixing and association thermodynamic properties of liquid Na-TI alloys at three temlperatures are reported. A thermodynamic model is developed and fitted to these with success but the failure of the model to fit the properties of Na-Ga is reported. The problems involved in fitting thermodynamic models are discussed.

The electrical resistivities of 3d-transition (V and Ti) and 4d-transition solutes (from Y to Ag except for Tc) in liquid tellurium have been measured from the melting temperature to about 850°C. The measured additional resistivities are positive for the “less than half” transition solutes and are negative for the “more than half”. They don't agree with Friedel theory. The additional resistivities have been explained with the number of the conduction electrons which increases with the addition of the “more than half” transition solutes and decreases with the addition of the “less than half” on the basis of the formation of sp-d mixing near the pseudo-gap. The additional resistivities of transition solutes in liquid tellurium change as a sine function of the number of d-electrons per solute ion.

The temperature dependences of the magnetic susceptibilities of liquid Au-Zn and Au-Cd alloys have been measured. Curves of the susceptibilities of these alloys for all concentrations show rather a big deviation from the linearly interpolated ones. With the increase of temperature, these curves approach the interpolated curves. This fact might be related to the change of clustering in the liquid state, which approaches a random mixture with the increase in temperature.

The experimental study of residual resistivity and magnetic susceptibility of dilute alloys of nickel in liquid bismuth is presented. The increase in resistivity by the addition of one atomic percent nickel amounts to 0.45 µΩ cm. The localized electrons of nickel are non-magnetic in liquid bismuth and the increase in the susceptibility by d -state of additional one percent nickel is 0.2×10 -6 C. G. S. e. m. u . It is concluded that the density of the virtual bound state of nickel in liquid bismuth is not so large compared with that of the conduction electron.

Magnetic Susceptibilities of 3 d -transition metals in liquid tin are measured. Alloys of Sn-Mn are magnetic and obey the Curie law, while the other alloys such as Sn-Ni, Tn-Co, Sn-Fe, Sn-Ti and Sn-V are non-magnetic. These data are discussed using the Friedel-Anderson scheme.

Electrical resistivities and thermopowers of 3 d -transition metals in liquid tin are measured. The data are analized under the concept of virtual bound state. The number of localized electron of Ni, Co and Fe in liquid tin is estimated using the experimental data. From the thermopower, the state density of the virtual bound state at Fermi level and the effective contribution of Coulomb and exchange interaction U +4 J are estimated.

The structure of nickel in the liquid state has been studied by neutron diffraction at 1500 °C. After calculating the interference function (Fourier analysis), the atomic radial distribution function was evaluated from which interatomic distance and coordination number were obtained. Die Struktur von Nickel im flussigen Zustand wurde mit Neutronenstrahlen bei 1500 °C untersucht. Nach der schon ofter dargestellten Methode (Fourier-Analyse) wurde die Interferenzfunktion in eine radiale Atomverteilungsfunktion transformiert, aus der sich der mittlere Abstand nachster Atome und die Koordinationszahl ergeben.

The electrical resistivities of dilute 3 d -transition metals in liquid antimony are measured. The resistivity changes by 1 at % of 3 d -transition metals, Δ ρ, are small magnitude within \(\pm 2{\mu}\varOmega\) cm. These small changes are mainly attributed to the d -resonant scattering. The t -matrix formulation based on Ziman theory is used for the estimation of Δ ρ in which we ignored the all η's contribution other than η 2 since the d -resonance seems to be dominant compared with other scatterings. Some discrepancies between experimental results and calculated values are found, while both changes have a same tendency.

Neutron diffraction measurement has been carried out in order to investigate the structure of molten silver iodide. The observed total structure factor and the pair distribution function of molten ...

As part of the systematic research on the phase stability of alkali halides, the phase diagram of the CsCl-RbCl system was determined by using differential scanning calorimetry (DSC) with the help of high-temperature X-ray diffractometry. It is indicated from the phase diagram that the CsCl-enriched solid solution which possesses rocksalt structure and the RbCl-enriched solid solution which also possesses rocksalt structure separate into two phases below 803 K. It is stressed that the elimination of the thermal hysteresis by annealing is important in the precise determination of phase diagram of this system.

The structures of liquid Ce-Ni alloys with 25 and 75 at.% Ni have been investigated by X-ray diffraction. The results suggest that the charge transfer effect makes a major contribution to the effective hard core diameter of Ce-Ce pairs in these alloys.

The effective interatomic potentials of liquid Te and Se have been derived from the observed structural data using the Born-Green equation. The effective interatomic potential of liquid Te has long range oscillation in real space as the same as in simple liquid metals but has a little difference for its oscillating phase near the region of the first and second nearest neighbour distances. While the effective interatomic potential of liquid Se has not shown the oscillating behaviour but is similar to that of molecular liquids like Ar.

The value of ultrasonic examination and ultrasonically guided needle biopsy (UGNB) of mediastinal masses was investigated in 45 patients. Fifteen of the masses were malignant and 30 were benign. The diagnoses were histologically confirmed by examination of surgical or autopsy specimens. Only teratoma could be confidently diagnosed by ultrasonography alone. Diagnosis of other types of mediastinal masses required examination of tissue samples. Using ultrasonically guided aspiration biopsy (UGAB), we were able to diagnose 13 of 15 malignant tumors and 18 of 27 benign mediastinal masses. Ultrasonically guided cutting biopsy was performed in conjunction with UGAB in 11 patients, and the diagnosis was histologically confirmed in 9 cases. Complications with UGNB occurred in only 1 case. Our results indicate that UGNB is a safe, simple technique that can be applied to most of the mediastinal masses. We believe that it is the method of choice in such cases.

The microscopic electron theory based on the pseudopotential formalism has been applied to the calculation of the heats of mixing and of activities in liquid Al-Sn alloys. The calculated values for both quantities were found to be in reasonable agreement with the experimental data.

A new theoretical equation for interaction parameter in multicomponent metallic solutions is developed using the pseudopotential formalism coupled with the free energy of the hard sphere system. The approximate expression for the pseudopotential term is given in terms of the heat of solution at infinite dilution, to allow easy evaluation of the interaction parameter in various multicomponent systems. This theory has been applied to 23 non-ferrous alloys based on Pb, Sn, Bi and indium. Comparison with the results of previous theoretical calculations using only the hard sphere model suggests that the inclusion of the pseudopotential term yields a quantitatively more correct prediction of interaction parameters in multicomponent metallic solutions. Numerical calculations were also made for 320 Fe-base solutions relevant to steelmaking and the agreement between calculation and experimental data appears reasonable, with 90% reliability in predicting the correct sign.

Mediastinal lymph nodes metastasis of lung cancer was analysed by endoscopic ultrasonography in 96 patients in whom histological diagnosis of the lymph nodes could be proven by thoracotomy. A Receiver Operating Characteristic (ROC) curve was drawn up for determining the criteria for metastatic lymph nodes by endoscopic ultrasonography. The ROC curve was evaluated by using four parameters: The long diameter, the short diameter, the long diameter plus the short diameter, and the product of the long diameter times the short diameter. The long plus short diameter and the long-times-short diameter showed the highest detectability of the metastasis of all histological types on the ROC curve. The reasonable criteria levels were found to be 18 mm and 75 mm2 by means of a moderate threshold. In this level, sensitivity were 77%, 76%; specificity 84%, 84%; and accuracy 82%, 82%, respectively. When examinations were done by histological types, the criteria level for the epidermoid carcinoma should be increased to more than that for the adenocarcinoma. And, sensitivity and specificity were better in the epidermoid carcinoma. Thus, these results suggest that endoscopic ultrasonography is clinically useful for the detection of lymph nodes metastasis in lung cancer.

The significance of ultrasonography was tested in evaluation of cancerous invasion into the pleura and chest wall in patients with lung cancer. The degree of the invasion was ultrasonographically classified into four grades, that is, uP-0, uP-1, uP-2 and uP-3, corresponding with the classification proposed by the Japan Lung Cancer Society, which is graded by surgical findings. The total accuracy of this method was 77 percent. Especially for uP-3, which is the most critical grade regarding decisions on surgical intervention, this figure was 100 percent. It is suggested that this approach can delineate cancerous invasion into the pleura and chest wall sufficiently well for daily clinical use and staging of patients with lung cancer.

A breakdown of the additivity of the specific heat is found in liquid Na-Tl alloys. The maximum deviation of the additional specific heat occurs near the equiatomic composition.

The temperature dependence of the interference function of liquid Zn-Bi alloys has been measured by neutron diffraction method. Its main peak changes rapidly with temperature in a complicated manner, which very probably reflects the immiscible characters of Zn and Bi atoms.

Mesures des susceptibilites magnetiques de 50 o C en dessous de la temperature du liquidus jusqu'a 500 o C. Etude de l'ordre a courte distance

A calculation of the heat of mixing in liquid alkali alloys is presented. The two body correlation function is used in the calculation. The theoretical value compares satisfactorily with the experimental one in the Na-K system.