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The sheet resistance ( R sk ) underneath ohmic Au-electrodes on hydrogen-terminated surface-conductive diamond (001) surfaces was examined by a special current-voltage measurement. It has been found that R sk is about ~ 200 times larger than the sheet resistance, R sh , in the open areas without Au-electrodes. The specific contact resistance, R C , of ohmic Au-electrodes on H-terminated surface-conductive diamonds as determined by linear transmission line models must be corrected accordingly. As the results of this, R C is suggested to be of the order of 1 × 10 − 3 – 1 × 10 − 4 Ωcm 2 .

In this work, an axial-type vibration energy harvester with an impact-sliding structure that uses a magnetostrictive Permendur (Fe-Co-V) rod was produced and its power generation properties were measured. It was found that all the peak frequencies analyzed using the FFT method from the experimentally obtained voltage waveforms were consistent with the calculated inherent frequencies of the axial vibration of the rod. Therefore, the power generation by the proposed harvester likely resulted from the inherent axial vibration of the magnetostrictive rod. Furthermore, the maximum output energy obtained in this work was 1592 µJ, which was generated by a harvester with 3000 coil turns and two magnets under a load resistance of 3 kΩ. It was found that the maximum output energy was generated when the load resistance was close to the coil impedance at the inherent frequency of the axial vibration of the rod.

Ni incorporated Fullerene (C 60 ) nanowhiskers have been prepared by liquid–liquid interfacial precipitation method. The prepared nanowhiskers were characterized using various analytical tools such as optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and micro-Raman spectroscopy. The microscopic images reveal that the formation of tubular and non tubular nanowhiskers with fine dispersion of Ni atoms in the nanowhiskers. The TEM mapping analysis confirms the presence of Ni atoms in the nanowhiskers. XRD analysis and the electron diffraction pattern substantiate the presence of fcc crystalline structure and Raman spectroscopy reveals the polymerization of nanowhiskers.

A novel microporous carbon nitride material (Mic-CN-1) with very high surface area and pore volume has been prepared for the first time by nanocasting technique using MCM-22 zeolite as a template through a simple polymerization reaction between ethylenediamine and carbon tetrachloride. The material has been thoroughly characterized by XRD, N-2 adsorption, TGA, HRSEM, HRTEM, XPS, FT-IR, and U-V-vis spectroscopy. It has been found that the surface area of the Mic-CN-1 is much higher than that of the parent template and the mesoporous carbon nitride. We suppose that the novel CN material with microporous structure could offer great potential for the applications, such as catalytic supports, gas storage, lubricants, the size selective adsorption of small organic molecules such as amino acids and vitamins. (C) 2007 Elsevier Inc. All rights reserved.

An image analysis method for measuring bubble velocity fields at high bubble number density is proposed. It is based on computing the cross correlation of bubble images with multiple spatial resolutions, i.e. a recursive cross correlation technique. Comparing several PTV and PIV schemes, it is confirmed that the recursive cross correlation leads to the best measurement results because of the robustness with respect to optical and dynamic characteristics of bubbles. The method is applied successfully to the measurement of bubble motion in bubble plumes accompanying a strong unsteadiness over a wide frequency range. The results reveal that the high frequency fluctuations of bubble velocities grow in the shear layer and near the top surface, while low frequency fluctuations dominate in the middle part of the tank. The characteristic frequency divides the frequency spectrum of the bubble fluctuation intensity into two regions: where there are turbulent behaviors and where there are macroscopic convection patterns in the bubble plumes.

In order to investigate its electronic structure and the π – d interaction, we studied magnetoresistance (MR) of β ″ -(EDO-TTFVO) 2 FeCl 4 . In the course of experiment Shubnikov–de Haas (SdH) effect was found, which shows that this material is a 2D metal. Below 3.5 K (close to T N ), MR shows a dip anomaly near 8 T . The anomaly becomes more prominent and shifts slightly to higher field with lowering temperature. The dip anomaly may be caused by the transition from the antiferromagnetic to the paramagnetic states. In addition, SdH oscillations are clearly seen at 0.5 K , whose cross-sectional area corresponds to 13% of the first Brillouin zone. The mass of the π -electrons is m * ≃ 3.3 m e , which seems heavy as compared with non-magnetic organic conductors with similar cross-sectional areas, suggesting the enhancement of the mass due to magnetic interaction with the Fe 3d spins.

Olefin insertion into Ti-methyl bonds of methyltitanium chloride clusters on a TiCl 3 crystalline surface has been studied by using paired interacting orbitals (PIO). We have shown that at least two types of active sites can be assumed on the edge of the basal face of violet TiCl 3 crystallites: a edge type active site which possesses a dangling bonded Cl atom, four bridged Cl atoms and a Cl vacancy and a corner type active site which possesses a dangling bonded Cl atom, three bridged Cl atoms and two Cl vacancies. The size effects on these active site have been estimated by changing the number of titanium atoms of the TiCl 3 model clusters. The most important interaction in the olefin coordinated state is electron delocalization from the occupied Ti d xz orbital of the methyltitanium chlorides to the π∗ orbital of the coordinated olefin molecule, while in the transition state is electron delocalization from the occupied C p and Ti d xz orbital of the methyltitanium chloride species to the π∗ orbital of the olefin. These interactions are compactly shown in PIO's. The coordination energy and the activation energy for the olefin insertion are almost independent of the cluster size when the number of Ti atoms is greater than three. The corner type active site has been shown to be stabilized at the transition state by the absence of one of the Cl atoms which are located orthogonal to the insertion plane. Thus, the olefin insertion on the corner type active site is more favorable than that on the edge type active site. In the case of propylene insertion, syn -orientation of propylene is favored. This regioselectivity should be lower on the corner type active site than that on the edge type active site.

The philosophical and practical differences between Japanese and American IC industries concerning VLSI reliability, as well as recent research topics and new analysis methods such as wafer scale testing are discussed. A new challenging approach to VLSI reliability is now greatly needed in response to the “paradigm shift” now being brought about by simple scaling limitations, increased process complexity, and VLSI application to advanced systems. A good example of this shift is the new movement from simple failure analysis by sampling the output of a manufacturing line to the “building-in-reliability” approach. To pursue this technique, greater importance will be attached to a deeper physical understanding (including frequent use of Computer Aided Design, CAD/ Design Automation, DA) of the significant relationships between the input variables and product reliability, and to total concurrent engineering from research labs to production sites. In addition, distributive quality control management being carried out particularly in Japan, where quality improvement is the common concern for every employeee, may be a key factor in overcoming the more difficult reliability problems in the coming giga-scale ICs. Furthermore, fast new VLSI testing methods and new yield-enhancing redundancy techniques, resulting in cost reduction, will be increasingly needed to achieve high reliability for VLSIs with 109 devices on a single chip.

The mechanism of the active site formation in Ziegler polymerization catalysts has been studied using the paired interacting orbitals (PIO) based on an extended Huckel calculation. Deformation of a titanium chloride molecule and partial dissociation of an organoaluminum dimer have been shown to take place by approaching the two species together. A six membered cyclic intermediate complex has been formed in a reaction plane, involving the Ti atom, the C atom, two Al atoms, the Cl* atom and the bridging atom. An elongation of the CAl bond, Al-bridging atom bond, the TiCl* bond and shrinkage of the CTi bond take place in concert in the transition state region. Key factors of activating the complex are the valency of the titanium and the structure whether or not it has a Cl anion trans to the Cl* atom. An active site is the complex between the alkylated titanium chloride and the aluminum chloride produced in the course of the reaction. The formation of the active site in titanium chlorides/organoaluminum systems has been clarified to become easier in the following order: d 1 -Sq (square) pyramidal ⪢ d 0 -Sq pyramidal ⩾ d 0 -hinge like titanium chloride. d 0 -triangle pyramidal titanium chloride is unfavorable for the formation of active sites.

The effect of structural changes of methyltitanium complexes on regioselectivity in propylene insertion into the methyl-Ti bond was studied by applying paired interacting orbitals (PIO). Electron delocalization from the HOMO of the methyltitanium fragment to the π* orbital of the olefin and electron delocalization from the π orbital of the olefin to the unoccupied orbitals of the methyltitanium fragment are important for the olefin insertion. At the same time a repulsive orbital interaction arises between the HOMO of the methyltitanium fragment and the π orbital of the olefin. The HOMO of the d 0 -methyltitanium compounds is composed mainly of C m p orbitals and subsidiarily of Ti d z 2 orbital, the composition being not sensitive to the structure of the methyltitanium compounds. The π orbital of propylene has a slightly larger amplitude on C β , while the π* orbital has a slightly larger amplitude on C α . When the methyltitanium compounds and the propylene interact in the syn -form, electron delocalization is facilitated and overlap repulsion is reduced. The primary insertion of propylene is thus favored. The repulsion appears between the methyl group of titanium compounds and the methyl group of propylene. In the anti -form, the repulsion exists between the ligand of the titanium compound and the methyl group of propylene. The repulsion in the anti -form is sensitive to the structure of the methyltitanium compounds. Therefore, the more the space around the titanium is filled with ligands, the stronger the repulsion becomes. As a result, the selectivity of primary insertion of propylene on the d 0 -methyltitanium complexes becomes higher in the following order: octahedral > square pyramidal > trigonal bipyramidal > tetrahedral. In d 1 complexes electron delocalization occurs strongly from the SOMO of the methyltitanium compound to the π* orbital of propylene both in the syn -form and in the anti -form, however this electron delocalization is not conducive to insertion. The primary insertion is favoured, but it is not so easy as in the d 0 complexes. By using PIO analyses, we have clarified the importance of the delocalization interaction in determining the regioselectivity in the insertion of propylene into methyl-Ti bonds.

The effect of ligands on ethylene insertion into the methyl-titanium bond of O h -d 0 methyltitanium complexes was studied using paired interacting orbitals (PIO). The most important contribution to this insertion was shown to be electron delocalization from the methyltitanium compound to ethylene, and the next is electron delocalization from ethylene to the methyltitanium compound. The ligand effect, which favors ethylene insertion into the O h d 0 methyltitanum complexes, is summarized as follows: an electron-attracting ligand should be placed at a position trans to ethylene, and an electron-donating one trans to the methyl group; ligands placed at the positions perpendicular to the reaction plane play the role of introducing the ethylene monomer into the reaction site. The effect of coordination of MgCl 2 on the insertion is also discussed.

T-phase organic quasi-two-dimensional conductors have a 4-fold single Fermi surface (FS) from band calculation. At low temperature, the resistivity turns into semiconducting, whereas Shubnikov-de Haas oscillations have been observed. The amplitude of the oscillation is quite large because the system is near the quantum limit (N=2-state) under -27 T. The observed oscillations include two frequencies that are inconsistent with the band calculation. The reason of this discrepancy may be explained by the reconstruction of the FS. In this work, we examined very high magnetic field transport property up to 60 T and reconsider the low temperature crystal structure of this salt by diffuse X-ray study.

The origin of the formation of a CH → Ti bond in a methyltitanium complex was studied by use of Paired Interacting Orbitals (PIO). Methyl group tilt is flavoured when there is a ligand trans to the methyl. An electron-donating ligand axial to the tilting plane causes methyl to tilt into an agostic position. This methyl group tilt in the opposite direction is not favoured because of the overlap repulsion between the ligand orbital and orbitals of the methyl group. The PIO technique elucidates the properties such as structures, reactivity and stability of transition metal complexes.

Insertion of ethylene into the methylTi bond of ([CH 3 Ti(Cl) 4 /C 2 H 4 ] n , n = −1 or −3) Oh- d 0 , - d 2 and [CH 3 Ti(Cl) 2 /C 2 H 4 ] n , n = +1 or −1) Td- d 0 , - d 2 methyltitanium complexes has been studied by applying Paired Interacting Orbitals (PIO). It is important for the insertion that the PIOs are in-phase between the methyl carbon and the ethylene C β , and between the Ti and the ethylene C α . This condition is satisfied in d 0 complexes. In d 2 complexes the orbital pair in the PIO-1, which consists mainly of the occupied Ti d xz and the unoccupied ethylene π * MO, overlap out-of-phase between the methyl carbon and the ethylene C β . We can predict that, whereas the ethylene insertion is facile in d 0 methyltitanium complexes, it is not in d 2 complexes.