Takehiro Matsuse

Electrical Conductivity of Microwave Heated Polyaniline Nanotubes and Possible Mechanism of Microwave Absorption by Materials

In the course of experiments to perform deprotonation and carbonization of doped polyaniline (PANI) nanotubes (NTs) by irradiating directly 2.45 GHz microwave (MW) in our microwave heating system (MWHS), we have discovered that the PANI-NTs self heat by absorbing the MW, but the temperature of the PANI-NTs stops rising around 300 °C in spite of the heightened MW power. Furthermore, we have found that the MW irradiated PANI-NTs have transferred from electrical conductor to insulator depending on the temperature of the PANI-NTs. By measuring electron spin resonance (ESR) spectra of the MW heated PANI-NTs, the existence of the unpaired electrons is shown to have a strong correlation between the degree of MW absorption and the transition in the electrical conductivities. In order to deprotonate and carbonize further the PANI-NTs, we have performed heat treatment for the PANI-NTs up to a temperature (T) of about 1200 °C in the same MWHS using carbon fiber which self heats by absorbing MW. The chemical transformations in the PANI-NTs induced by the heat treatments are discussed by measuring the X-ray photoelectron spectroscopy (XPS) spectra. Finally, the temperature dependence of electrical conductivities of the PANI-NTs are measured in order to investigate the mechanism of electrical conduction of the heat treated PANI-NTs.

Unique molecular structure and properties of novel purple intermediates of phthalocyanine derivative

When long alkylthio-substituted phthalocyaninato copper(II) complexes, (CnS)8PcCu, were rapidly prepared in an α-diol by using our developed see-through microwave reactor and/or a conventional hot stirrer, novel purple intermediates were selectively obtained instead of the expected green complex, (CnS)8PcCu, for some specific combinations of the reaction solvent and metal salt. The reaction conditions to obtain the purple intermediates were established and the unique molecular structure was clarified for a buthylthio-substituted intermediate by X-ray single crystal structure analysis.

Controlled Microwave Irradiation for the Synthesis of YBa 2Cu 3O7-x Superconductors

For synthesizing a high-quality YBa2Cu3O7-x superconductor using a domestic microwave oven without any post-heat treatment, the power and time of microwave irradiation are controlled by monitoring continuously the temperature of the microwave-heated sample. The temperature is measured by means of a metal-sheathed chromel-alumel thermocouple which is installed in the oven in the proper way. The conditions of the sample inside the oven are almost the same as the sample environment proposed by Kato et al. [Jpn. J. Appl. Phys. 36 (1997) L1291]. The maximum monitoring temperature where crystal growth occurs rapidly for a high-quality YBa2Cu3O7-x superconductor is shown to be about 500°C which is much lower than the maximum heating temperature in the conventional method.

Discotic liquid crystals of transition metal complexes, 54 : Rapid microwave-assisted synthesis and homeotropic alignment of phthalocyanine-based liquid crystals

The most difficult problem on syntheses of the phthalocyanine-based liquid crystals is the long reaction time. In order to shorten the reaction time, we have developed novel Methods A, B and D, for the syntheses of phthalocyanine-based liquid crystals by using microwave heating and/or adding a phase transfer catalysis of Aliquat 336. A series of phthalocyanine derivatives CnPcZn(1) (n= 10, 12, 14, 16 and 18: a, b, c and e) could be successfully synthesized in a dramatically short reaction time of 30–60 min using Methods A and B by microwave heating. On the other hand, anothor series of the derivatives Cn(OH)PcZn (2a–2e) could not be synthesized by microwave heating. Therefore, all these derivatives were synthesized using conventional Method C by oil bath heating, but the reaction took a very long time (22.5–88 h). To shorten the reaction time, we have developed Method D by oil bath heating with adding a phase transfer catalyst of Aliquat 336. In this method, we successfully shortened the reaction time fro...

BAND LIKE ELECTRONIC STRUCTURES IN SQUARE HOLLOW QUANTUM DOTS BY 3D-MHFKS CALCULATION

To find novel aspects of the electronic structures in quantum dots (QD) from a view point of spatial broken symmetry, 3-dimensional-mesh Hartree-Fock-Kohn-Sham (3D-MHFKS) calculations1 are applied to the interacting electron system of electron number N in a symmetry broken hollow QD. For the case of a square hollow quantum dot confined in square hard wall (HW) potential (SSHQD), the magnetic (B) field dependence of the obtained single particle energy levels and chemical potentials in B-N diagram are shown to have a band like electronic structures over the wide B-field range up to 20T. To clarify the origin of the band like electronic structures in SSHQD, 3D-MHFKS calculations are also applied for the mixed symmetry QDs with a circular hollow in square HW potential (SCHQD) and with a square hollow in circular HW potential (CSHQD).

New application method of input-output table for industrial structure change

Publisher Summary It is important to clarify the repercussion effect of a technology innovation generated in a certain industry on the industrial structure of a society in terms of the economy and the environment. This chapter presents a new input-output (IO) table that considers the repercussion effect in accordance with the basics of the original IO table constructed. To evaluate the repercussion effect, not only the Leontief inverse matrix for repercussions to sectors of raw materials is utilized, but also the demand-repercussion inverse matrix for repercussions to demand sectors is taken into consideration. To show the reliability and applicability of the new methodology, the result for the implementation of high strength steel (super metal) is presented in the chapter as an example of a technology innovation. This method can also be used to calculate the change in CO 2 emissions resulting from the technology innovation. The discussion indicates that the implementation of a new technology decreases the gross domestic product (GDP) due to the reduction in product weight. A method for restoring the GDP and constructing a new IO table is also developed and explained with respect to economic structural change.

Interaction between Na-clusters by semi-microscopic model and comment on fission process

To elucidate the fission process of doubly charged Na clusters, a simple model calculation in a core approximation is presented for the cases of Na162+ and Na202+ clusters by utilizing the unrestricted Hartree-Fock method. The existence of unstable states of doubly charged cluster created by an ionization of singly charged cluster without shape-change is shown as a possible origin for fission to occur. By comparing the calculated interaction barriers of almost asymmetric and symmetric channels, it is shown that the deformation effects are strong in the large separation regions to evaluate the fission barriers by the use of two touching spherical clusters.