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991.
Jiraporn Klanwan Takafumi Seto Takuma Furukawa Yoshio Otani Tawatchai Charinpanitkul Masamichi Kohno Makoto Hirasawa 《Journal of nanoparticle research》2010,12(8):2747-2755
Gas suspended single-walled carbon nanotubes (SWCNTs) with single tube diameter smaller than 2 nm and length of longer than 500 nm were generated by simple and continuous system using laser ablation technique under atmospheric conditions. Graphite target containing 0.5 wt%-nickel and 0.5 wt%-cobalt was ablated by Nd:YAG laser in an electrical furnace under atmospheric pressure of nitrogen flow that allowed one step and continuous synthesis of the SWCNTs. Size distribution of the gas suspended SWCNTs aerosol was measured using size-classification by a differential mobility analyzer (DMA) coupled with a condensation particle counter (CPC) used as a detector. Characteristics of SWCNT aerosol generated under the different temperature were also investigated using scanning and transmission electron microscopes and Raman scattering. Mono-mobility SWCNT aerosol with mobility diameter of 100 and 200 nm was successfully prepared after the size separation using a DMA. 相似文献
992.
Effective design of a dye-sensitized solar cell (DSSC) requires a clear understanding of the reaction mechanisms of the constituent
cell materials. The relationship between structural and photo-electrochemical properties of the photo-anodic materials is
of the first priority for such investigations. Highly oriented aggregates of anatase phase TiO2 nanoparticles were deposited on Indium Tin oxide (ITO) glass substrates; over which N719 dyes were adsorbed through electrophoretic
deposition under a strong magnetic field. The properties were evaluated by electrochemical measurements, UV–VIS spectroscopy,
and electrical resistance measurements. The results showed that the absorbed photon number in the TiO2 aggregates with adsorbed dye and their resistivity showed different dependences on the orientation of the crystal plane in
the TiO2 particle. The dependence of the photocurrent on the plane orientation of aggregates of dye-sensitized TiO2 nanoparticles has been determined from a combination of the electrical conductivity of TiO2 aggregate and the amount of dye adsorbed on the surface of TiO2. 相似文献
993.
Metallic Contaminant Detection using a High-Temperature Superconducting Quantum Interference Devices Gradiometer 下载免费PDF全文
Saburo Tanaka Tomohiro Akai Makoto Takemoto Yoshimi Hatsukade Takeyoshi Ohtani Yoshio Ikeda Shuichi Suzuki 《中国物理快报》2010,27(8):253-255
We develop magnetic metallic contaminant detectors using high-temperature superconducting quantum interference devices (HTS-SQUIDs) for industrial products. Finding ultra-small metallic contaminants is an important issue for manufacturers producing commercial products such as lithium ion batteries. If such contaminants cause damages, the manufacturer of the product suffers a big financial loss due to having to recall the faulty products. Previously, we described a system for finding such ultra-smafi particles in food. In this study, we describe further developments of the system, for the reduction of the effect of the remnant field of the products, and we test the parallel magnetization of the products to generate the remnant field only at both ends of the products. In addition, we use an SQUID gradiometer in place of the magnetometer to reduce the edge effect by measuring the magnetic field gradient. We test the performances of the system and find that tiny iron particles as small as 50 × 50 μm^2 on the electrode of a lithium ion battery could be clearly detected. This detection level is difficult to achieve when using other methods. 相似文献
994.
Investigation of cadmium accumulation mechanism in hepatopancreas of Patinopecten yessoensis by synchrotron radiation X‐ray absorption fine structure and synchrotron radiation X‐ray fluorescence analyses 下载免费PDF全文
Kenji Terada Yoshinari Abe Izumi Nakai Shingo Maruhashi Shigetoshi Miura Kotaro Honda Yasuhiro Tomooka 《X射线光谱测定》2018,47(2):137-143
Chemical state of cadmium in a hepatopancreas of a scallop (Patinopecten yessoensis) was studied by means of synchrotron radiation‐based X‐ray analytical techniques. X‐ray absorption fine structure (XAFS) and X‐ray fluorescence (XRF) imaging were used to identify the chemical state and the distribution of cadmium in the hepatopancreas, respectively. The results of in vivo Cd K‐edge XAFS suggested that the neighboring atoms of the cadmium in the hepatopancreas are of sulfur. Therefore, we propose that cadmium was accumulated by a metalloprotein with sulfur. Micro XRF imaging of thin sections of the hepatopancreas showed that cadmium is distributed on the surface of intestinal epithelia and concentrated in the internal tissue of the hepatopancreas. These results indicated that scallops accumulate cadmium inside the hepatopancreas through the intestinal epithelium. 相似文献
995.
Nobuhiko Sawaki Toshiki Hikosaka Norikatsu Koide Shigeyasu Tanaka Yoshio HondaMasahito Yamaguchi 《Journal of Crystal Growth》2009,311(10):2867-2874
Adopting anisotropy etching method, a (1 1 1) facet of Si is obtained on a Si substrate and selective area growth (SAG) of GaN is performed with metal-organic vapor phase epitaxy on the facet. The epitaxial lateral overgrowth of (1 1¯ 0 1), (1 1 2¯ 2) GaN is investigated on (0 0 1) and (1 1 3) Si substrate, respectively, and the incorporation properties of Si, C, and Mg elements are discussed in relation to the atomic configuration on the surface. Analyzing the optical and electrical properties of C-doped (1 1¯ 0 1) GaN layer, it is shown that carbon creates a shallow acceptor level. On the thus prepared (1 1¯ 0 1) GaN layer, a light emitting diode (LED) with a C-doped p-type layer is fabricated. 相似文献
996.
Baba T Yokoya T Tsuda S Kiss T Shimojima T Ishizaka K Takeya H Hirata K Watanabe T Nohara M Takagi H Nakai N Machida K Togashi T Watanabe S Wang XY Chen CT Shin S 《Physical review letters》2008,100(1):017003
We have performed temperature- (T-)dependent laser-photoemission spectroscopy of the antiferromagnetic (AF) superconductor ErNi2B2C to study the electronic-structure evolution reflecting the interplay between antiferromagnetism and superconductivity. The spectra at the superconducting (SC) phase show a very broad spectral shape. A T-dependent SC gap shows a sudden deviation from the BCS prediction just below TN. This observation can be explained well by the theoretical model and thus represents the characteristic bulk electronic structure of the AF SC phase for the first time. 相似文献
997.
Kenji Ishida Hiroshi Murakawa Yoshio Kitaoka Yoshiteru Maeno 《Journal of Physics and Chemistry of Solids》2008,69(12):3108-3114
We review our nuclear-magnetic resonance (NMR) and nuclear-quadrupole-resonance (NQR) studies in superconducting Sr2RuO4, which have been performed in order to investigate the gap structure and the pairing symmetry in the superconducting state and magnetic fluctuations in the normal state. The spin-lattice relaxation rate (1/T1) of a high-quality sample with shows a sharp decrease without a coherence peak just below Tc, followed by a T3 behavior down to 0.15 K. This result indicates that the superconducting gap in pure Sr2RuO4 is a highly anisotropic character with a line-node gap. The Knight shift, which is related to the spin susceptibility, is unchanged in the superconducting state irrespective of the direction of the applied fields and various magnitude of the field. This result strongly suggests that the superconducting pairs are in the spin-triplet state, and the spin direction of the triplet pairs is considered to be changed by small fields of several hundred Oe. 相似文献
998.
Norio Murayama Susumu Soeya Yoshio Takahashi Masaaki Futamoto 《Journal of magnetism and magnetic materials》2008
Microstructure variation of FePt thin film upon annealing at elevated temperatures was investigated by transmission electron microscopy (TEM). A special shape aperture was employed to observe the ordered L10 phase in the dark-field TEM images. With increasing the annealing temperature, crystal grains formed clusters with gathering of neighboring grains, and crystal grain growth proceeded within the cluster. L10 ordered crystal grains were preferentially formed near the grain boundaries, and their sizes grew with increasing the annealing temperature. 相似文献
999.
1000.
Intrauterine devices (IUDs) have been viewed as an effective form of contraception. However, the mechanism by which IUDs disturb fertility remains controversial. This study aimed to evaluate the effects of IUDs on uterine contractility using cine MR. Eleven healthy female volunteers of reproductive age bearing IUDs and 12 women not bearing IUDs were evaluated during the periovulatory phase. MR images were obtained with a 1.5-T magnet, acquiring 60 serial images every 3 s via half-Fourier acquisition single-shot turbo spin echo to be displayed on cine mode. Assessments were based on (a) the presence of peristaltic waves, (b) the frequency and direction of peristaltic waves and (c) the extent of peristaltic waves. Static images were evaluated for thickness of the junctional zone (JZ) and myometrium. A fundo-cervical (FC)-directed peristaltic wave was identified in 4 of 11 IUD-bearing subjects and in only 1 of 12 subjects from the control group. FC waves extended through more than half of the thickness of the myometrium. Peristaltic frequency in IUD users (5.0/3 min) was less than that of the control group (6.5/3 min). The JZ and myometrium were significantly thicker in IUD users. FC-directed waves were more often observed in IUD-bearing subjects, which might explain the inhibition of active sperm transport. 相似文献