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91.
Tsukino H Hanaoka T Sasaki H Motoyama H Hiroshima M Tanaka T Kabuto M Turner W Patterson DG Needham L Tsugane S 《The Science of the total environment》2006,359(1-3):90-100
This study evaluates background serum levels of selected organochlorine compounds among Japanese women of reproductive age and investigates whether lifestyle factors, especially dietary factors, may be associated with these levels. A cross-sectional study was performed on 80 Japanese women, aged 26-43 years, who complained of infertility and were confirmed not to have endometriosis. The serum levels of total toxic equivalency (TEQ), 18 polychlorinated dibenzo-p-dioxins (PCDDs)/polychlorinated dibenzofurans (PCDFs), 4 coplanar polychlorinated biphenyls (cPCBs), 36 ortho-substituted polychlorinated biphenyls (PCBs), and 13 chlorinated pesticides or their metabolites were measured and data were collected on the women's age, residence, occupation, body mass index (BMI), smoking and alcohol habit and 6 dietary intakes (fish, meats, rice, vegetables, fruits and dairy products). The serum median level of total TEQ was 25.1 pg TEQ/g lipid, that of PCDDs/PCDFs/cPCBs was 11.5 pmol/g lipid, that of PCBs was 0.46 nmol/g lipid, and that of total pesticides was 1.32 nmol/g lipid. The serum levels of total TEQ, PCDDs/PCDFs/cPCBs, PCBs and pesticides were positively associated with age (P for trend=0.003, 0.01, 0.005 and 0.01, respectively) and frequent fish consumption (P for trend=0.002, 0.003, 0.0003 and 0.006, respectively). Other lifestyle factors were not associated with serum organochlorine levels. The present study suggests that Japanese women who consume fish frequently in their reproductive period tend to accumulate organochlorines in their bodies. 相似文献
92.
Yuji Sasaki Philippe Rapold Makoto Arisaka Masaru Hirata Takaumi Kimura Clément Hill 《溶剂提取与离子交换》2013,31(2):187-204
Abstract Extraction of Eu(III) and Am(III) from HNO3 into the organic solvents using N,N,N′,N′‐tetraoctyl‐diglycolamide (TODGA) was investigated in order to study the detailed extraction reaction. The chemical species: 1:2 for metal:TODGA complex is present in polar diluents. On the other hand, the metal complexes need three or more TODGA molecules to remain stable in non‐polar diluents. The HNO3 concentration dependence on the distribution ratio suggests that HNO3 participates in the metal extraction. Infrared spectra indicate that the carbonyl oxygen coordinates with Eu(III), and luminescence lifetimes suggest that there are no water molecules in the inner coordination sphere of the extracted Eu‐complex. 相似文献
93.
Takuya Honma Ikue Sasaki Nobuhiro Tamura Junichi Tatami Shinichiro Fujichika Katsutoshi Komeya Takeshi Meguro 《International Journal of Applied Ceramic Technology》2013,10(2):348-353
To fabricate functionally graded materials, a highly concentrated slurry of SiO2‐Mo system was prepared and centrifugal force was applied in an attempt to achieve a graded composition. Subsequently, we formed a homogeneous green body with compositional gradation by floc‐casting at 80°C, which was then fired at 1750°C for 10 min in Ar. The sintered body had compositional ratios of SiO2 and Mo as well as electrical conductivities that changed gradually along the direction of centrifugal force. The results demonstrate that centrifugation and control of slurry characteristics such as flocculation are effective in fabricating functionally graded SiO2‐Mo materials. 相似文献
94.
Yoshihiko Okada Kaori Sasaki Baiqian Zhong Hideki Ishida Takeshi Mitsuda 《Journal of the American Ceramic Society》1994,77(5):1319-1323
A mixture of CaO and silicic acid prepared with a Ca/Si ratio of 2.0 was hydrothermally synthesized at 80° to 200°C, and the thermal decomposition behavior of the products (C-S-H with Ca(OH)2 ) was analyzed using XRD, 29 Si MAS NMR, and the trimethylsililation method (TMS). It was found that the main silicate anion structure of C-S-H was a mixture of a dimer and a single-chain polymer (larger than Si5 O16 ) and that polymerization advanced with an increase of the synthesizing temperature. On heating, the products decomposed to form β-C2 S. It was found that the decomposition was gradual and that the-higher the temperature of hydrothermal synthesis, the lower was the temperature of the decomposition into β-C2 S. Although the decomposition proceeded to form a monomer (β-C2 S) from the polymer and dimer, this dimer was resistant to heat and did not decompose unless heated to above 400°C. 相似文献
95.
Imaging of optical disc using reflection-mode scattering-type scanning near-field optical microscopy
Yamaguchi M Sasaki Y Sasaki H Konada T Horikawa Y Ebina A Umezawa T Horiguchi T 《Journal of microscopy》1999,194(PT 2-3):552-557
A phase-change optical disc was observed using a reflection-mode scattering-type scanning near-field optical microscope (RS-SNOM). In an a.c.-mode SNOM image, the 1.2 microm x 0.6 microm recording marks were successfully observed although the data were recorded on the groove. In contrast, no recording marks could be resolved in a d.c.-mode SNOM image. These results are in good agreement with those from a numerical simulation using the finite difference time domain method. The resolution was better than 100 nm with a.c.-mode SNOM operation and the results indicate that recording marks in phase-change optical media can be directly observed with the RS-SNOM. 相似文献
96.
Ninomiya Yuma Sasaki Hideaki Yoshikawa Takeshi Maeda Masafumi 《Metallurgical and Materials Transactions B》2019,50(1):407-415
Metallurgical and Materials Transactions B - The dissolution and passivation of pure Cu and Cu-5 wt pct Ag anodes in H2SO4-CuSO4 electrolyte were investigated by a direct... 相似文献
97.
Sang-Hyun An Takuya Matsumoto Jun-Ichi Sasaki Hiroyuki Miyajima Ramaswamy Narayanan Satoshi Imazato Kyo-Han Kim 《Materials science & engineering. C, Materials for biological applications》2012,32(8):2516-2522
Anodization is an easily viable technique useful for producing TiO2 coatings on titanium substrates. Nano-crystalline anodic TiO2 structure was produced on titanium at 20 V using 1 M Na2SO4 and 0.5% NaF and consolidated by a further heat-treatment. Micro-crystalline anodic TiO2 was produced on titanium by applying a galvanostatic current density of 70 A/m2 in water medium. To assess the usefulness of these nano- and micro-oxides for bone implant stability, physical properties and bone in vitro bioactivity including HA formation, cellular affinity and mouse-tissue morphogenesis, were evaluated. Bioactivity of the different anodic surfaces was evaluated by treating them in a simulated body fluid (SBF) to form hydroxyapatite (HA) and the rates of HA formation were compared. Deposits of HA could be seen on the nano-oxide surface within 7 days, whereas HA was detected only after 14 days on the micro-oxide surface. In vitro cell culture tests done using mouse osteoblasts indicated that the nano-oxides showed statistically significant cell activity than the micro-oxides and the machined titanium. Branching morphogenesis test done for 72 h on these surfaces showed more branching on the micro- and nano-oxides as compared with titanium surface. 相似文献
98.
Liang Y Nakamura S Cui L Johkura K Ogiwara N Sasaki K 《Journal of electron microscopy》2004,53(1):93-97
Three-dimensional microlocalization of adhesion molecules, i.e. ICAM-1 (intercellular adhesion molecule), VCAM-1 (vascular adhesion molecule), LFA-1 (lymphocyte function-associated antigen), Mac-1 (macrophage differentiation antigen) and VLA-4 (very late activation antigen), expressed on type-A synoviocyte (macrophage-like cell) and type-B synoviocyte (fibroblast-like cell), were detected by immuno-scanning electron microscopy (SEM) to investigate the immunoreactive microenvironment of the superficial synovial intima in lipopolysaccharide (LPS)-induced arthritis of the mouse knee. Type-B synoviocytes extended rich slender processes from the periphery and constructed a cytoplasmic network, to which ICAM-1 was restricted. VCAM-1 was expressed only in the LPS-stimulated group and was relatively limited to the microvilli of type-B synoviocytes. Type-A synoviocytes were located randomly among the network with a smoother surface and expressed Mac-1 and LFA-1, which were counter-receptors for ICAM-1, and VLA-4 for VCAM-1 on the microvilli or lamellipodia. Three-dimensional microlocalization of adhesion molecules suggests that the network constructed by cytoplasmic processes and microvilli of type-B synoviocytes forms the pathway for the migration or the foothold for the fixation of type-A synoviocytes and takes part in forming an immunoreactive environment in the articular cavity. 相似文献
99.
S.N. Markin S.N. Ermolov M. Sasaki R.G. van Welzenis H.H. Brongersma 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(15):2433-2436
A peculiarity in the backscattering of keV He+ ions by a well-ordered high-purity W(2 1 1) surface is reported. Besides the normal elastic binary collision peak and the low-energy tail due to backscattering in deeper layers, an extra peak is observed for an inelastic loss of about 95 eV. This unusually large loss has a constant value over a wide range of primary energies (1.5-4.5 keV). An extra peculiarity is that the peak is only observed for the scattering in normal incidence towards the (2 1 1) plane. It is also not seen for polycrystalline W. The energy loss may be due to a quasi-double or -triple collisions of He particles with the row-trough structure of W(2 1 1) involving electronic excitation of both He and W atoms. Alternatively it may be due to a special channeling/dechanneling process for the incident ions. 相似文献
100.
A fuel irradiation program is being conducted using the experimental fast reactor ‘Joyo’. Two short-term irradiation tests in the program were completed in 2006 using a uranium and plutonium mixed oxide fuel which contains minor actinides (MA-MOX fuel). The objective of the tests is the investigation of early thermal behavior of MA-MOX fuel such as fuel restructuring and redistribution of minor actinides. Three fuel pins which contained MA-MOX: 2% neptunium and 2% americium doped uranium plutonium mixed oxide (Am,Pu,Np,U)O2−x fuel were supplied for testing. The first test was conducted with high-linear heating rate of approximately 430 W cm−1 for only 10 min. After the first test, one fuel pin was removed for examinations. Then the second test was conducted with the remaining two pins at nearly the same linear power for 24 h. In these tests, two oxygen-to-metal molar ratios were used for fuel pellets as a test parameter. Non-destructive and destructive post-irradiation examinations results are discussed with early on the behavior of the fuel during irradiation. 相似文献