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排序方式: 共有1747条查询结果,搜索用时 109 毫秒
991.
Matsushima S Sasaki F Sarumaru S Ohta D Era S Sogami M Inaba T Kinosada Y 《Magnetic resonance imaging》2003,21(9):1045-1047
In the breast carcinamas, sentinel lymph node biopsy (SLNB) attracts attention as technique to be settled by axillary lymph node metastasis, but existence of a false negative case is a problem. Equivalent cross relaxation rate image (ECRI) is the measurement method that we can evaluate a change of organization structure quantitatively by magnetic resonance imaging. We executed axillary ECRI as a purpose with decreasing a false negative case of SLNB. ECRI related to a macroscopic image, and it was possible to evaluate yes or no of axillary lymph node metastasis. ECRI is the useful method to evaluate adaptability of SLNB. 相似文献
992.
Takayuki Iwasaki Tasuku Maki Daisuke Yokoyama Hironori Kumagai Yasuhiro Hashimoto Takuma Asari Hiroshi Kawarada 《固体物理学:研究快报》2008,2(2):53-55
Vertically aligned double‐walled carbon nanotubes (DWCNTs) with the highest selectivity of 90% were synthesized by a controlled heating method and their electric double‐layer capacitor characteristics were evaluated. DWCNT arrays had a specific capacitance of 83 F/g, which is one of the highest values among CNT arrays in a nonaqueous solution and is almost equivalent to that for single‐walled CNT (SWCNT) arrays reported previously. At the same specific capacitance, DWCNTs with superior structural properties are more promising for practical capacitors than SWCNTs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
993.
Alignment-free optical modules using solder-bump-bonding technique for free-space optical interconnections 总被引:1,自引:0,他引:1
We propose alignment-free optical modules using a solder-bump-bonding technique for constructing free-space optical interconnection
systems without a special alignment procedure. Bonding pads for mounting an optoelectronic device chip are fabricated by exposing
a photosensitive resin film to light traveling through the optical system of the module so that the image positions of the
bonding pads on both image planes of the optical interconnection system are aligned with each other. A device chip is mounted
by solder-bump bonding and is set at a proper position by the surface tension of molten solder. The effectiveness of the technique
is verified by constructing alignment-free optical modules. 相似文献
994.
Yasuyuki Takeda Kiyokazu End
Daisuke Yoshiyama Katsusige Watanabe Naoaki Fukada Shoichi Katsuta 《Journal of Molecular Liquids》2007,130(1-3):21-28
The constants of overall extraction equilibrium (Kex) and partition (KD,MLA) for various diluents and aqueous ion-pair formation (KMLA) of alkali metal (Li–Cs) picrate (MA) 1:1:1 complexes (MLA) with benzo-18-crown-6 (B18C6) and its open-ring analogue 1,2-bis[2-(2-methoxyethoxy)ethoxy]benzene (AC·B18C6) were determined at 25 °C, L being B18C6 or AC·B18C6; the distribution constants of AC·B18C6 were measured at 25 °C. The partition behavior of AC·B18C6 and the MLA complexes closely obeys regular solution theory, omitting chloroform; the molar volumes and the solubility parameters of AC·B18C6 and the MLA complexes were determined. The extraction selectivities of AC·B18C6 and B18C6 for the alkali metal picrates increase in the order Li < Na < Cs < K or Rb < or ≈ Rb or K and Li Na < Cs < Rb < K, respectively. The extraction selectivity of B18C6 for neighboring alkali metal ions in the periodic table is superior to that of AC·B18C6. The macrocyclic effect on the extraction-ability and -selectivity was quantitatively elucidated by the four fundamental equilibrium constants. 相似文献
995.
We propose techniques of hologram replication in glass plates and reconstruction on another film by corona charging. A surface
relief hologram on an azobenzene polymer film was recorded in the form of electric polarization in glass plates that include
alkali cations by corona charging at high temperature. The hologram recorded in the glass plate is stable for more than 1
month at room temperature. After removal of the azobenzene polymer film from the plate, poly(methyl methacrylate) (PMMA) film
was spin-coated onto the plate. The hologram recorded in the plate was reconstructed with the same surface relief structure
on the PMMA film by corona charging again at 110°C. 相似文献
996.
997.
Haruo Seto Kazuo Furihata Noboru Otake Yasuhiro Itoh Shuji Takahashi Tatsuo Haneishi Muneki Ohuchi 《Tetrahedron letters》1984,25(3):337-340
The structure of a fungal metabolite, oxyrapentyn has been determined as shown in Fig. 7 by application of a new NMR technique, long range J C-H resolved 2D spectroscopy (LRJR). 相似文献
998.
Four new guaianolides, sinodielides E-H (1-4), were isolated from the root of Sinodielsia yunnanensis WOLFF. Their structures were established by spectral evidence. 相似文献
999.
Naoki Yokoyama Nobuaki Tanaka Natsumi Fujimoto Dr. Rika Tanaka Prof. Dr. Shuichi Suzuki Prof. Daisuke Shiomi Prof. Dr. Kazunobu Sato Prof. Dr. Takeji Takui Prof. Dr. Masatoshi Kozaki Prof. Dr. Keiji Okada 《化学:亚洲杂志》2021,16(1):72-79
A nitronyl nitroxide unit ( NN ) was linked with a triphenylamine-based condensed polycyclic skeleton DOTT to form a radical substituted donor NN - DOTT . X-ray crystal structure analysis demonstrated a flat bowl shape of the DOTT unit. EPR spectra showed the localization of electron spin on the NN unit. Chemical oxidation of the DOTT unit produced radical-substituted radical cation salts NN - DOTT + ⋅ SbF6− and NN - DOTT + ⋅ FeBr4− that are stable under ambient conditions. The magnetic behavior of NN - DOTT + ⋅ SbF6− is characterized by the strong intramolecular ferromagnetic interaction between NN and DOTT +. The X-ray structural analysis of NN - DOTT + ⋅ FeBr4− shows planar structure of DOTT and 1D mixed-stack column of NN-DOTT + and FeBr4−. Magnetic measurements established that NN - DOTT + ⋅ FeBr4− undergoes magnetic phase transition into a weak ferromagnet at 7 K. 相似文献
1000.
Kiyoshi Suzuki Takahiro Totsuka Daisuke Ishiguro Shun Okubo Hidetaka Tobita 《大分子反应工程》2021,15(1):2000040
A following new interpretation of apparent induction period is proposed considering the experimental results obtained: octamethylcyclotetrasiloxane (D4) is activated by the reaction with acid to generate an activated derivative (A4). A4 reacts with D4 to generate A8, an active species containing eight dimethylsiloxane units. A8 backbites to generate mostly A4 and D4, which causes retardation in polymerization, but occasionally to form A3 and D5. A3 is highly reactive, and when the concentration of A3 exceeds a certain limit, much Ai where i is large enough is formed and promotes fast growth of chain at the interfacial area due to high concentration of D4. The interpretation assumes that A3 accelerates growth of chain faster than other species, and that A8 tends to backbite rather than grow. The interpretation is supported by the experimental results of polymerization conducted with D4 and D3, or D5 and D3 charged. 相似文献