The CuO/Cu2O nanowire axial heterostructures were fabricated by a thermal oxidation technique in air. These nanowire structures resulted from CuO nanowire growth followed by Cu2O formation. These nanowires were divided into two regions. One is the top half part of the nanowire with CuO domains, and the other part is the bottom half of the wires with Cu2O domains. The structural property of the CuO/Cu2O nanowire axial heterostructures was clarified in detail. Both the CuO and the Cu2O have domain boundaries parallel to the growth direction. The specific relationship of the crystalline orientation between the CuO and Cu2O shows that CuO [110] or [110] is nearly parallel to Cu2O [110] mostly along the growth directions. The growth condition dependence of the morphological structure was also examined. A simple axial nanowire heterostructure fabrication technique using the compositional modification was developed.

The investigation of physical and physicochemical properties of transition metal complexes containing two or more metal centres in close proximity is a very important research area, which has led to the proposal of several models for some biochemical processes. 1,2 Many metalloenzymes contain two divalent transition metal ions in close proximity and in most cases the two metal centres cooperate with each other 3 and they have contributed to a better knowledge of oxygen transport as well as of some industrial catalytic processes. 4,5 Binuclear copper(II) complexes are of general interest as they are very useful model systems for biological studies and also for deriving magneto-structural correlations. [6][7][8] The known Cu(II)-phenolate complexes usually exhibit coordination numbers ranging from 4 to 6, as is typical for the coordination chemistry of Cu(II). The phenolates in most of these compounds usually are incorporated as part of multidentate ligand systems 9,10 and so complexes with simple, exogenous phenolate ligands are less common. 11 In this connection, recently some efforts to synthesise trinuclear copper complexes have been communicated. 12,13 The relationship between the peculiar spectroscopic properties of polynuclear complexes and their structural features is crucial to characterise protein models and can help in the understanding of reaction mechanisms or reaction details at the active site. Hightlighting this phenomenon, Bermejo and co-workers reported two interesting µ-phenoxo bridged Copper(II) trimeric complexes. 4,13 However, trinuclear doubly phenoxobridged metal complexes of transition metals are still very sparse in the literature. 14 Herein, we describe the single crystal X-ray structure, spectroscopic study and low-temperature magnetic properties of a novel doubly phenoxo-bridged trinuclear copper(II) complex (1), with a tetradentate Schiff base ligand (H 2 L) in which the central copper atom posses square planar and the two terminal copper atoms share square pyramidal geometry.The ligand H 2 L was synthesised by refluxing a 25 ml methanolic solution of 2-hydroxy acetophenone (2 mmol) and 1,3-diamino propane (1 mmol) for an hour. The resulting mixture gave a brown solution containing the liquid ligand which is used for the synthesis without further purification.The ORTEP representation of the trinuclear unit for 1 is shown in Fig. 1 with important bond lengths and angles summarised in Table 2. Complex 1 crystallises in the monoclinic system with space group P2(1)/n. There are two types of geometrically different copper(II) centres, with a N 2 O 3 donor set for Cu1 and an O 4 donor set for Cu2. In the trimeric unit, the copper atoms are held together by doubly µ 2 -phenolate oxygen of the tetradentate Schiff base ligand. In this structure, the Cu1…Cu2 distance is 2.

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This paper describes an improved micrometer electrode system for the measurements of dielectric constant, dissipation factor, and mean thickness of sheet specimens in a wide frequency range and its appplication to a series of measuring methods. The influence of the edge capacitance and the residual impedance of this electrode system has been decreased to a negligibly small amount by the adoption of a shield ring and improvements in construction of the electrode system. The characteristics of the system are easily examined by using its electrode gap fine adjustment mechanism, which is developed for a series of measuring methods. In case the varying gap immersion method is adopted, the imperfect contact between the electrodes and the specimen and the residual impedance of the system do not affect the results, even at the highest frequency. Furthermore, the measurements are limited to only the gap variations and the resonance voltage ratio, and are freed from those of the electrode gap length, the electrode area, and the specimen thickness. Therefore, the measuring and calculating processes are so simplified that they take only a few minutes for each specimen, and in a series of methods, the best results are obtained without any correction in a wide frequency range from 1 to 200 MHz. The resolution is limited by the sensitivity and stability of the adopted apparatus such as a Q meter. The accuracy reaches ±0.2% for dielectric constant and ±2% or 3 μrad for dissipation factor, respectively, even at the highest frequency of 200 MHz.

This paper describes an improved method and apparatuses based on it for the measurement of the dielectric constant and the dissipation factor at very high frequencies. This method is a combination of the Hartshorn and Ward, Lynch, and liquid immersion methods. The direct purpose is to measure low-loss polyethylene which is to be used in submarine telephone cables at 36 and 100 MHz in Japan. By using a 0.5∼2.0 mm thick disk specimen, the dielectric constant can be measured to an accuracy of 0.3%, the dissipation factor to several μrad, and the mean thickness to several μ without any kind of correction. The three equations for them are simple and independent of the frequency. This method is easy to use and takes little time, for the values to be measured for each specimen are only three in a series of measurements, and the mechanical thickness measurements are not required.