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We report successful introduction of negatively charged nitrogen-vacancy (NV(-)) centers in a 5 nm thin, isotopically enriched ([(12)C] = 99.99%) diamond layer by CVD. The present method allows for the formation of NV(-) in such a thin layer even when the surface is terminated by hydrogen atoms. NV(-) centers are found to have spin coherence times of between T2 ~ 10-100 μs at room temperature. Changing the surface termination to oxygen or fluorine leads to a slight increase in the NV(-) density, but not to any significant change in T2. The minimum detectable magnetic field estimated by this T2 is 3 nT after 100 s of averaging, which would be sufficient for the detection of nuclear magnetic fields exerted by a single proton. We demonstrate the suitability for nanoscale NMR by measuring the fluctuating field from ~10(4) proton nuclei placed on top of the 5 nm diamond film.

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HIZEN celadons produced at Arita and Imari areas in Japan from 1630's to 1790's (Edo period) have been investigated by means of X-ray fl uorescence analysis, and X-ray diffraction and X-ray absorption spectra using synchrotron radiation. It is found that, in the HIZEN celadons, the color brightness of the celadon glazes depends on the structural property of the raw basic ceramics taken at Imaizumi (Arita) and Ohkwachi (Imari), where the former is mainly Quartz-SiO 2 , and the later is Sanidine ((K,Na)Si 3 O 8 ). It is confi rmed that CaCO 3 of natural wood ash added artifi cially into the raw celadon ceramics makes a glassy glaze on the surface of the basic body of the HIZEN celadons. Transition-metal ions (Cr, Cu, Zn) of very small amount are detected in the celadon glazes, in addition to Fe and Mn of small amount. It is considered that Cu and Cr are related to the color brightness of green-brown and blue-green in the HIZEN celadon glazes, respectively. Keywords: HIZEN celadons, celadon glaze, microstructure. Resumo Celadons (http://www.ceramicanorio.com/aprendendoourelembrando/celadon/celadon.html) Hizen produzidos nas áreas de Arita e Imari no Japão nos anos de 1630 a 1790 (período Edo) foram investigados por meio de análise de fl uorescência de raios X, difração de raios X e espectros de absorção usando radiação síncrotron. Foi descoberto que nos celadons Hizen o brilho na coloração dos esmaltes celadon depende da propriedade estrutural da matéria-prima cerâmica extraída em

To develop new tribomaterials for mechanical sliding parts, investigations were carried out on the influence of adding styrene–ethylene/butylene–styrene block copolymer (SEBS) on the rheological, mechanical, and tribological properties of polyamide 6 (PA6) nanocomposite, which is a commercial product of layered silicate (clay) filled polyamide 6 (PA6/Clay). Two kinds of block copolymers, unmodified SEBS (SEBS) and maleic anhydride‐grafted SEBS (SEBS‐g‐MA), were added with PA6/Clay nanocomposite. Dynamic viscoelastic properties in the molten state of these nanocomposites and their tensile, impact, and tribological properties of these nanocomposites were evaluated. Dynamic viscoelastic properties were found to increase with the addition of SEBS and were influenced, in particular, by block copolymers containing SEBS‐g‐MA. Influence of the addition of SEBS on mechanical properties of these systems differed for each mechanical property. Although tensile properties decreased with SEBS, Izod impact properties were improved with the addition of SEBS‐g‐MA. Tribological properties were improved with the addition of block copolymer, and the influence of the amount of addition was higher than the type of block copolymer used. These results indicate that new tribomaterials developed have sufficient balance amongst moldability, mechanical, and tribological properties. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers

Frequency dependence of the dielectric properties of La-doped lead zirconate titanate thin films with Pt and Ir electrodes and two different La doping levels is studied by impedance spectrometry between 10−3 and 104 Hz. A constant phase element with an impedance of Z=A0(jω)−α is introduced into the equivalent circuit, which fits very well both the real and imaginary components of the measured impedance over the full frequency range, including the resonance, using a single α (0≪α<1). Our analysis shows that α is not related to the ferroelectric properties of the films, but it has a monotonic correlation with the real dielectric constant. The close resemblance to the well-known butterfly-shaped C–V curve shown by α with the applied dc bias (α-V) suggests that α may be affected by the density of the domain walls in the film, in addition to various dielectric relaxation processes.

We have developed a method to separate the low-resistive near-interface regions (NIRs) from the high-resistive central bulk region (CBR) in a ferroelectric thin film. The NIR thickness and the CBR resistivity can thus be accurately determined. Using lanthanum-doped lead zirconate titanate films as an example, we show that the total thickness of the NIRs depends only on the electrode materials in use (Ir and Pt), while the CBR resistivity depends only on the impurity doping levels (La=1.5% and 3%). The fact that the NIR is much narrower when Pt electrodes are used instead of Ir, and that the NIR resistivity is always considerably lower than the central bulk, suggest that the NIRs is probably originated from material nonstoichiometry/defects rather than the band bending at metal/insulator interfaces.

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