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Thin films of ordered double perovskite Sr2FeMoO6 were sputter-deposited on Ba0.4Sr0.6TiO3-buffered SrTiO3 substrates, and their surface properties were examined by atomic force microscopy (AFM) and X-ray photoemission spectroscopy (XPS). The Mo 3d spectra of Sr2FeMoO6 films showed a multiple peak structure, which originated from the unusual electronic state of metallic Sr2FeMoO6. Systematic XPS studies of the air-exposed surface of Sr2FeMoO6 film indicated that the surface native barrier was an insulating SrMoO4. In addition, a TMR junction with the native barrier was fabricated using a convention photolithographic technique, and an MR ratio of 10 % was observed at 4.2 K.

We report studies on Andreev reflection measurements of ferromagnetic materials at junction interfaces using AlN/NbN junctions. We found that the junction resistance R can be controlled by varying the thickness and growth temperature of an AlN interlayer. The spin polarization of Co was determined to be PCo ≈ 0.44 from theoretical fitting of the conductance data for these junctions. The behavior of PCo and the dimensionless barrier parameter Z depending on the junction resistance R is discussed.

A 16-dimensional Cayley-Dickson algebra is presented. Its unique algebraic properties, its zero-divisors, and the solutions to a general linear equation are found. A theory of function is developed in terms of the regularity (monogenicity) conditions and some such functions are constructed.

Zinc oxide/metal oxide multilayered composite thin film varistors have been fabricated by the radio-frequency (RF, 13.56 MHz) sputtering method and the electrical properties of the films were investigated. After the Au electrode was formed on a quartz substrate by vacuum evaporation, zinc oxide (ZnO) layer was deposited by the RF sputtering with ZnO target at room temperature, Ar partial pressure of 2.5 Pa, O 2 partial pressure of 2.5 Pa and RF power of 50 W. Praseodymium oxide (Pr 6 O 11 ) layer was formed on the ZnO layer by the RF sputtering with Pr 6 O 11 target at room temperature, Ar pressure of 5 Pa and RF power of 80 W. The upper Au electrode was formed on the Pr 6 O 11 layer by vacuum evaporation. The conduction mechanism of the ZnO/Pr 6 O 11 double-layered thin film varistor was discussed on the basis of the measurements of voltage-current ( V - I ) and capacitance-voltage ( C - V ) characteristics and thermally stimulated current (TSC). From the results of V - I and C - V measurements, it was found that a depletion region was formed in the ZnO layer close to the interface between ZnO and Pr 6 O 11 layers.

Sodium−hydrogen−C60 ternary compounds have been prepared by intercalation of sodium hydride (NaH) into C60. This method afforded a high-quality superconducting (SC) sample with a large volume fraction, but on the other hand, only a few high-quality SC samples were obtained and most of the samples were nonsuperconducting. However, we have succeeded in transforming a non-SC sample into an SC sample and in enhancing superconductivity. The Rietveld analysis clarifies that the non-SC phase (α-phase) has an orthorhombic structure, in contrast to a cubic structure for the SC phase (β-phase). The absence of superconductivity in the α-phase will be understood by the broken symmetry.

This paper reports the magnetic, electrical, and microstructural properties of epitaxial thin films with an ordered double-perovskite structure. Sr/sub 2/ FeMoO/sub 6/ (SFMO) and Sr/sub 2/ CrReO/sub 6/ (SCRO) films have been grown by sputtering onto the lattice-matched substrates of Ba/sub 0.4/ Sr/sub 0.6/ TiO/sub 3/ -buffered and bare SrTiO/sub 3/, respectively. These films exhibit high saturation magnetization M/sub s/ values (3.8 /spl mu//sub B//f.u. for SFMO and 0.9 /spl mu//sub B//f.u. for SCRO), which are close to the expected values for their half-metallicity, and high curie temperature T/sub c/ values (385 K for SFMO and 620 K for SCRO). Surface analyzes by AFM and XPS indicate that these films have atomically flat and well-defined surfaces, which are free from any surface precipitates. This enables us to employ a standard photolithographic process for fabricating magnetic tunnel junctions based on these films. SFMO junctions with a native barrier formed by surface oxidation of a SFMO base-electrode and a Co counterelectrode have shown a tunnel magnetoresistance ratio of 10% at 4.2 K.

We have found a new superconducting (SC) phase with the nominal composition (NaH) 4 C 60 , which was prepared by direct intercalation of sodium hydride (NaH) in C 60 . In a SQUID magnetization measurement, the SC transition temperature was found to be 15 K and the SC volume fraction was estimated to be 65%. The large value of the volume fraction suggests the creation of a single phase. This was confirmed by the powder X-ray profile showing a single f.c.c. phase with a lattice constant a=14.356(3) A . Hydrogen in the SC sample was analyzed by thermal desorption spectroscopy.

The monoclinic form of BDNT-PF6 (m-BDNT-PF6) is characterized as a pseudo-one-dimensional half-filled Hubbard system from the electrical conductivity, magnetic susceptibility, and single crystal optical spectra. m-BDNT-PF6 undergoes a spin-Peierls transition at about 150 K. The lattice dimerization was confirmed by the evolution of the vibronic modes at low temperature. The small polaron binding energy of this compound, which was estimated through the analysis of the vibronic modes, is smaller than those of TTF, TCNQ, or CA. Hubbard parameters U and t were obtained to be 0.8 and 0.13eV by analyzing the charge-transfer band. The optical and magnetic data are consistent with each other. Die monokline Form von BDNT-PF6 (m-BDNT-PF6) wird auf Gund von Messungen der elektrischen Leitfahigkeit, magnetischen Suszeptibilitat und optischen Einkristallspektren als pseudoein-dimensionales halbgefulltes Hubbard-System charakterisiert. m-BDNT-PF6 erfahrt einen Spin-Peierls-ubergang bei etwa 150 K. Die Gitterdimerisation wurde durch die Entwicklung der Schwingungsmoden bei niedriger Temperatur bestatigt. Die geringe Polaron-Bindungsenergie dieser Verbindung, die durch Analyse der Schwingungsmoden abgeschatzt wurde, ist kleiner als bei TTF, TCNQ oder CA. Die Hubbard-Parameter U und t wurden mittels Analyse des Ladungstransferbandes mit 0,8 und 0,13 eV bestimmt. Optische und magnetische Daten stimmen miteinander uberein.

We have found a novel organic semiconductor, BTQBT, with a high electrical conductivity of about 10 -3 S cm -1 and a high Hall mobility of about 3 cm2 V1 s -1 at room temperature. We have also succeeded in measuring the temperature dependence of the Hall mobility. It varies with temperature as Τ -1 · 6 , which agrees with the theoretical Τ -1 '5 dependence for the mobility determined by lattice scattering. The characteristic transport property of BTQBT results from strong intermolecular interactions in the crystal, which is convinced by the energy dispersion with a bandwidth of about 0.5 eV from the theoretical and experimental band structures. PACS numbers: 72.20.-i, 79.60.-i

Angle‐resolved ultraviolet photoemission spectra using synchrotron radiation were measured for oriented thin films of bis(1,2,5‐thiadiazolo)‐p‐quinobis(1,3‐dithiole) (BTQBT) on graphite. From the photon energy dependence of normal emission spectra, the energy‐band dispersion of π‐bands were observed for the highest (HOMO) and next highest (NHOMO) bands. This is the first observation of intermolecular dispersion in a single‐component organic molecular crystal. The results demonstrate that the BTQBT molecules have a strong intermolecular interaction, which can be derived from the introduction of a covalent interaction between sulfur atoms in addition to the usual intermolecular interaction by van der Waals forces.

We have prepared sodium-doped C60 utilizing the thermal decomposition of sodium azide (NaN3). The strong low-magnetic field microwave absorption with a clear hysteresis was observed in the samples of NanC60 (n=3∼4), indicating the superconducting nature. By means of a SQUID measurement, the superconducting transition temperature is found to be around 12 K. Significantly, elemental analysis detected a nitrogen which was surely produced in the process of the thermal decomposition of NaN3. We suppose that this new superconducting phase will be NaxNyC60 where x is between 3 and 4, and y is unknown. This is the first superconducting material in Na-doped C60 without other alkali metals.

A conducting crystal of (phthalocyaninato)cobalt hexafluoroarsenate CoPc(AsF6)0.5 is prepared by an electrochemical method. Temperature-dependent electrical conductivity of dc and 9.4 GHz shows that CoPc(AsF6)0.5 is a narrow-gap semiconductor with activation energies of 327 K for dc and 138 K for 9.4 GHz. Thermoelectric power is +40 μV/K - +50μV/K in the range 100–300 K. The sign of the thermoelectric power is consistent with our earlier spectroscopic result that Pc ring is mainly oxidized contrary to the analogous material CoPcI. Optical spectrum along the c axis exhibits strong and weak peaks at 0.29 eV and 1.2 eV. Magnetic susceptibility is composed of a Curie-Weiss part with C = 0.056 emu mol−1 and a nearly temperature-independent part with the magnitude of 5 × D−4 emu/mol/ All these data indicates the localizaion of holes (U>4t) like in (TMTTF)2X and Ag(DMe-DCNQI)2. This localization seems to be related to the exchange interaction between the unpaired d-electron on Co and the π-electron on macrocyclic ligand.

The Raman scattering study of superconducting thin films of A 3 C 60 (A=K,Rb) carried out upon laser excitations at 1.16 and 2.41 eV have revealed the significant broadening and Fano-lineshapes of several low energy H g intramolecular modes with relative intensities and widths depending on excitation energies. The most interesting feature of the 1.16 eV excited spectrum is the wide asymmetric band at 400 cm −1 which can be assigned by Fano-shape fitting to enormously broadened H g (2) mode red shifted compared to its bare frequency of 408 cm −1. The narrowing of all lower H g modes in insulating A 6 C 60 phase indicates strong electron-phonon coupling of this Jahn-Teller modes in x =3 phase and suggests that this low energy vibrations are contributing to superconducting pairing. However the possibility to interpret the wide band at 400 cm −1 as the maximum of electronic background can not be ruled out yet and is supported by our preliminary observations of its disappearance at low temperature below T c .

We have used the combined microwave spectroscopy: the nonresonant microwave absorption in low-magnetic field (so-called LFS) together with conventional ESR for the search and study of superconductivity (SC) in the new family of fullerene molecular solids: C60, C70, C76, C78, C84 C90, and their alloys ((C60)1-y(C70)y), doped by different metals (K, Rb, In, and Ga) and iodine I2. These experiments fall into two categories: 1) Search for SC in higher fullerenes and study of the evolution of SC properties upon doping of pure (one component) fullerenes including Cm thin films. 2) Investigation of the Tc change in molecular alloys of Mx (C60)1-y(C70)y type. In the first category of experiments we discuss the evolution of LFS and ESR spectra upon variation of Rb-doping conditions: temperatures of doping: Td (C60), Td(M), and doping time td, and as a result we find the optimal conditions for vapour phase Rb-doping. Here we demonstrate that SC Tc appears and disappears with doping abruptly at a discrete v...

By means of non-resonant microwave absorption in low magnetic fields it is found that the superconducting Tc significantly decreases in 60% 13C isotope substituted K3C60 and Rb3C60. The exponent α of the isotope effect, Tcrmc1/mα, is estimated roughly to be α=1.2–2.25, much higher than predicted by the BCS theory. The intrinsic disorder is observed both in the wide-mass spectrum and the dramatically changed IR spectrum reflecting the inhomogeneous distribution of 13C isotopes in 13C60−n12C60 molecules. The large positive α supports the intramolecular vibronic pairing, and the decrease of the electron-vibron coupling λ due to the disturbed symmetry of Hg modes in mixed 13C60−n12Cn molecules is proposed to contribute to the enhanced α, in addition to the conventional isotope frequency shift.

We present a Raman scattering study of pristine and K doped C 60 at various doping levels by exciting in the near-IR at 1.16 eV. The normal metallic state of K 3 C 60 is characterized by a broad scattering background and by the resonance of low energy phonons in the range of 250–500 cm −1 . We assign the broad background to an electronic Raman scattering due to low energy electronic excitations. This spectral feature is indicative of an anomalous normal state behaviour and is similar to the case of high temperature ceramic superconductors. In the overdoped K 6 C 60 the squashing mode at 278 cm −1 shows a Fano resonance with the electronic scattering associated with localized electronic excitations which are characteristic of isolated regions of K 3 C 60 into the matrix of K 6 C 60 as a result of inhomogeneous doping. The Fano resonance indicates a specific electron-phonon coupling of this Jahn-Teller mode with low energy excitations and suggests that the symmetry of this electronic excitation is h g (i.e. the same of the coupled phonon mode). We discuss the nature of the anomalous electronic Raman scattering in terms of scattering from low energy excitations involving a low lying singlet band resulting from electron correlation and/or dynamical J-T distortion caused by the squashing mode.

We reported design and synthesis of new peri-condensed heterocycles which do not contain TTF type conjugated systems, that is, three isomers of dithiaperylenes (DTPR), one isomer of dithiapyrene (DTPY) and their methylthio or methylseleno derivatives. These donors showed two-stage redox behavior whose potentials are comparable to that of TTF. Good correlation was obtained between the oxidation potentials and the HOMO energies calculated by the PM3 method. A number of CT complexes prepared were classified into three groups, neutral, ionic, and non-V-shape groups. Among them, the non-V-shape group complexes contained highly conducting complexes including molecular metals. Most of the CT salts with inorganic anions having high conductivities showed lower electronic transition energies than 0.5 eV.

Thermal properties of tetrakis(alkyltelluro)tetrathiafulvalenes (TTeCn-TTF) are investigated using DSC technique. It is shown that combining tellurium substituted TTF skeleton with the alkyl chains of different length we got a variety of thermal properties due to a competition between the alkyl chains and the TTF moiety. This competition leads to a polymorphism and to an irregular dependence of the melting point as well as enthalpy and entropy of melting on the alkyl chain length between the carbon number n = 4 and 7. For the compounds with long alkyl chains (n > 6) the analysis of thermodynamic properties confirms the existence of the molecular fastener effect, i.e. fastening of the TTF skeletons and decreasing of the distances between them in the crystal structure by crystallization of the long alkyl chains.

A method of decomposition into external four dimensions and internal six dimensions of the wave equations of octonionic spinors in ten dimensions is given. To obtain the spinor wave equations in the external four-dimensional Minkowski space-time, octonions in the extra internal six dimensions are described. The zero-mode solutions of the extra six-dimensional octonionic wave equations are also argued, and the Dirac equations in the four-dimensional Minkowski space-time are derived. Moreover, we investigate a possibility of the chiral asymmetric fermions in four dimensions.

The paper presents measurements of the spin polarization of sputtered La0.7Sr0.3MnO3 (LSMO) films using Andreev reflection spectroscopy in planar junctions with a superconducting NbN counter-electrode.

This paper reports the magnetic, and electrical properties of epitaxial thin films with an ordered double-perovskite structure. High-quality Sr/sub 2/FeMoO/sub 6/ (SFMO) and Sr/sub 2/CrReO/sub 6/ (SCRO) films have been grown by sputtering onto the completely lattice-matched substrates of Ba/sub 0.4/Sr/sub 0.6/TiO/sub 3/-buffered and bare SrTiO/sub 3/, respectively. These films exhibit high saturation magnetization M/sub s/ values (3.8 /spl mu//sub B//f.u. for SFMO and 0.9 /spl mu//sub B//f.u. for SCRO), which are close to the expected values for their half-metallicity, and high-T/sub c/ values (385 K for SFMO and 620 K for SCRO). The atomically flat surfaces free from any surface precipitate enable us to employ a standard photolithographic process for fabricating magnetic tunnel junctions based on these films. Magnetic tunnel junctions are completed with a native barrier formed by surface oxidation of a base-electrode film and a Co counterelectrode, showing 10% tunnel magnetoresistance (TMR) ratio at 4.2 K for a SFMO film.

A number of fabrication techniques such as sputtering, chemical vapor deposition and laser ablation have been employed to prepare impurity-doped ZnO thin films. Among these techniques, the laser ablation method has many advantages such as high deposition rate and simple setup required for the film formation, and is suitable for obtaining thin films of compounds with excellent stoichiometric transfer of the target material. From a practical point of view, however, further improvements in the electrical, optical, and chemical properties of ZnO thin films are required. In the study, we demonstrate the preparation of impurity-doped ZnO thin films by the XeCl excimer laser ablation. Optimization of impurity content in the ZnO target and the effects of substrate temperature during deposition on the electrical and optical properties of the ZnO films mainly used as the transparent conducting material are investigated systematically.

The hydrogen desorption peak for NT appears at 820K, which is lower than C60. The desorption peak of nitrogen appears at around 500K for C60, while NT does not have significant desorption above 300K. Carbon monoxide shows the several desorption processes both for C60 and NT below 400K. The weak desorption peaks appear at around 500K and 750K for C60, and above 700K for NT. Van der Waals and chemical interactions depend on the carbon network and the lattice/site.

1. The effects of inhibition of acetylcholine (ACh)-induced hyperpolarization on dilatation of submucosal arterioles were investigated in the guinea-pig ileum. 2. In smooth muscles of the arterioles depolarized by Ba(2+) (0.5 mM) to about -40 mV, ACh (3 microM) repolarized the membrane to about -65 mV (hyperpolarization), irrespective of the absence or presence of L-N(omega)-nitroarginine (L-NOARG, 0.1 mM) and diclofenac (1 microM), and increased the diameter (dilatation). 3. Combined application of charybdotoxin (CTX, 50 nM) and apamin (0.1 microM), inhibitors of some types of K(+)-channels, abolished the ACh-induced hyperpolarization and dilatation. 4. 18 beta-Glycerrhetinic acid (18 beta-GA, 30 microM), a known inhibitor of gap junctions, depolarized the membrane to about -36 mV, either in the absence or in the presence of Ba(2+), with no associated contraction of the arterioles. In the presence of 18 beta-GA, ACh-induced hyperpolarization was abolished, however the dilatation was inhibited only partially, with associated inhibition of constriction produced by Ba(2+) and NA. 5. 18 beta-GA inhibited the dilatation produced by sodium nitroprusside, an NO donor. 6. The ACh-induced hyperpolarization and dilatation were abolished in the presence of 2-aminoethoxydiphenyl borate (30 microM), an inhibitory modulator of inositol trisphosphate receptor-mediated Ca(2+) release from intracellular stores. 7. It is concluded that in submucosal arterioles, hyperpolarizations produced by ACh have causal relationship to the arteriolar dilatation. 18 beta-GA did not induce parallel relationship between hyperpolarization and dilatation produced by ACh. 18 beta-GA may have unidentified inhibitory effects on agonist-mediated actions, in addition to the inhibition of gap junctions.

Only very rarely do multiple parapapillary choledochoduodenal fistulas occur concurrently with ampullary carcinoma. The following presents just such a case, which occurred in a 51 year-old Japanese female hospitalized for epigastralgia. Gastrointestinal fiberscopy (GIF) showed abnormal swelling of Vater's papilla. She was diagnosed as having ampullary carcinoma and choledochoduodenal fistulas, as determined by hypotonic duodenography (HDG), endoscopic retrograde cholangiopancreatography (ERCP) and from the histopathology of the ampullary mucosal biopsy. Pancreatoduodenectomy was performed. We postulated that the multiple fistulas were formed on the longitudinal fold of Vater's papilla by an ampullary carcinoma, and that the fistulas played a major role in bile drainage. As a result, jaundice was not seen throughout the entire clinical course. We report on the mechanism of fistula formation, with a review of the recent literature.

23Na and 1H NMR studies have been carried out for a NaxHyC60 superconductor The peak position of the 23Na NMR spectrum exhibits discontinuous upfield shift of 30 ppm at about 250 K, indicates a first order phase transition From the line shape of the 23Na spectrum obtained at 7 K, the quadrupole coupling constant tensor is evaluated to be |e2Qq/h|=3.7 MHz with the asymmetry parameter η = 0.95. The 1H NMR spectrum suggests an anionic hydrogen state with weakly delocalized nature.

In the 1940s, almost 50 years ago, phthalocyanines, several kinds of dyestuffs such as cyanines and polycyclic aromatic compounds were major objects of study, and the quantitative investigation of electrical conductivity of organic compounds was started. We started to observe the electrical conduction of polycyclic aromatic compounds in 1947. At the beginning of these works, we used violanthrone, isoviolanthrone and pyranthrone as examples of those polycyclics. [1] From the temperature dependency of conductivity measurements of the polycyclic aromatic series and also from their photoconductive characters, it was found that their electronic properties appeared to be semiconductive. From the accumulation of experimental results on the semiconductive character of this series, in 1954 we presented a paper to the Bulletin of the Chemical Society of Japan entitled Organic Semiconductors. [2] In the same year [3], we reported a conductive organic complex, the ‘perylene-bromine complex’, having only resistivity value of 8Ω cm.

The theory of functions of a real biquaternion variable and the solutions of Maxwell’s equations are recapitulated. A study of the application to diffraction of light by a slit or a hole in a screen is described.

A novel butterfly-shaped bis(1,3-dithiole) donors containing a fused naphthalene and a 1,2,5-thiadiazole ring afforded cation radical salts showing metallic temperature dependence of conductivity.

Novel TTF vinylogues with extended π-conjugation have been synthesized using an oxidative dimerization reaction of 1, 4-dithiafulvenes. The cation radicals of the derivatives with o-substituted phenyl groups are thermodynamically stable where the aryl units are twisted and the TTF vinylogue skeleton is planar. Some compounds afforded cation radical salts upon electrochemical oxidation. X-ray structure analyses revealed unusual crystal structures.

The magnetic properties of the superconducting sodium-hydrogen-C 60 ternary compound have been investigated by means of SQUID and ESR. The superconducting parameters (the penetration depth λ and the coherence length ξ) are estimated to be λ=2800 A and ξ=38 A using H c1 (0)= 90 G and H c2 (0)= 22 T. The spin susceptibility and the ESR linewidth decrease sharply below ~250 K, suggesting the presence of some phase transition.

Novel nonplanar bis(1,3-dithiole) donors with small on-site Coulomb repulsion afforded unusual cation radical salts as single crystals whose properties were strikingly affected by the incorporated solvent molecules.

The Na-doped C60 superconductor prepared from sodium azide (NaN3) were systematically studied. Superconducting (SC) transition temperature (Tc) was evaluated to be 12–17 K from the low-field signal (LFS) of microwave absorption (MA) measurement. Several parameters such as critical field of the Josephson junction, the bulk Hc1(0) and Hc2(0), the London penetration depth and coherence length were estimated from LFS and SQUID experiments. The Pauli contribution increases with increasing SC volume fraction, but Curie spins are still detected at the low temperature even in the best sample with 38% of SC volume fraction.

We have prepared Na4C60 samples by the different ways of the thermal decomposition of sodium azide NaN3. The superconducting (SC) samples were obtained by the decomposition under the dynamic vacuum, while the non-SC samples by the decomposition in the sealed tube. The SC sample was composed of two fee phases with a lattice constant a=14.207(5)A (phase A) and a=14.339(4)A (phase B). On the contrary, the non-SC sample had single fee phase which can be assigned to phase A. This result strongly suggests that phase B is the SC phase.

Low-magnetic field spectra (LFS) of microwave absorption in k-(ET)2[Cu(NCS)2] single crystal is found to be highly anisotropic: For magnetic field parallel to conducting planes (H ll bc) LFS maximum is shifted to high HM=400 G while its intensity and hysteresis width are strongly enhanced compared to LFS at H ⊥ bc indicating that fluxons easily penetrate between 2D conducting layers coupled by Josephson junctions. Temperature behaviour of LFS is also anisotropic: for H ll bc hysteretic LFS shows the onset at T∼10 K. However for H ⊥ bc hysteretic LFS disappears abruptly at T ∼ 8.5 K though noisy LFS without hysteresis can be found at temperatures above Tc.

Superconductivity (SC) in K-doped molecular alloys of C 60 and C 70 are studied by means of the nonresonant microwave low-field signal (LFS) and conventional ESR, and a LFS-search for SC in K x C 70 is performed. The critical temperature of K x (C 60 /C 70 ) determined at the onset of hysteretic LFS, decreases to T c =16K (at about 10% C 70 ), and T c =10K (at about 25% C 70 ), compared with T c =19K in pure K x C 60 suggesting the decrease of electron-phonon coupling. A strong multicomponent g=2 ESR signal appears and coexists with LFS at low T for SC composition of K x (C 60 /C 70 ) indicating presence of a non-SC metallic phase. At overdoping LFS disappears and a single ESR line is enormously broadened to Δ H pp (300K) = 80G. In K x C 70 doped under the same conditions the LFS is not detected, indicating absence of SC above 5K, while a narrow ESR single line appears.

This paper reports development activities for a new production management system aiming to obtain excellent product quality and high productivity by heightening the morale of the workers and by harmonizing the workers' human needs with the company's organizational needs In the course of proceeding with the development of the new production management system, first, the needs of workers as a whole and as individuals were analysed by the multivariate analysis method, so as to clarify the differences in their motivations in regards of the workers' attributes, working environments and the management systems Secondly, several proposals for improvement were presented to workers as a whole and as individuals and such proposed improvements were experimentally implemented one after another in order to harmonize the human needs with the organizational needs.

The classical Wheeler-Feynman absorber theory with a postulate of Lorentz-invariant zero-point electromagnetic radiation is proposed to explain quantum phenomena in a similar manner to that of stochastic electrodynamics. For this purpose, Cramer's model of a 'Minimum emitter-absorber transaction' is extended to the case where zero-point radiation exists, in the context of the classical Wheeler-Feynman theory. The Einstein-Podolski-Rosen paradox and the quantum levels of a charged simple harmonic oscillator are derived from the theory. It is shown that the condition for a transaction plays an essential role, such as in the radiative balance of a simple harmonic oscillator.

A theory of tachyons and superluminal transformations is developed on the basis of the quaternionic formulation. We have introduced a complex space-time and a complex transformation group which contains both Lorentz transformations and superluminal transformations. The complex space-time «the biquaternion space» which is closed under the superluminal transformations is introduced. The principle of special relativity, such as the conservation of the quadratic form of the metric of the space-time, and the principle of duality are extended to the complex space-time and to bradyons, luxons and tachyons under the complex transformations. Several characteristic features of the superluminal transformations and of tachyons are derived.

The equivalence between the octonion wave equation and the regularity condition for functions of an octonion variable with a condirion form of an octonion wave equation and is extended to an octonion equation equipped with four-dimensional mass space. The theory of functions of a split (complex)-octonion variable is developed and the solutions of the octonion wave equation and that of an extended Proca's equation are given within this framework.