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101.
Jae Cheol Lee Yong Koo Kyoung In Yong Song Jae Woo Lee Young Sik Shin Jin Seok Kim Shin‐ichi Iida 《Surface and interface analysis : SIA》2014,46(7):429-432
We have developed a simple and powerful method, which is called ‘angled sample holder method’, to characterize a topographic structured sample such as microsized via hole of ball grid array using time‐of‐flight SIMS. The diameter of via holes was 100 µm and the depth was 70 µm. To remove the shaded area by incidence primary ion beam and to extract secondary ions from the bottom of a via hole, several types of angled sample holders with compensation steering plate were applied on the basis of simulation results using SIMION code. And the analyses using angled sample holder method enabled us to characterize the bottom and side wall of a via hole in clear. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
102.
Katsumi Iida 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(3):897-904
Studies on the contribution to acetyl-CoA and oxaloacetic acid from the pyruvic acid transformation from l-alanine in Arthrobacter hyalinus were conducted by means of feeding experiments with l-[1-13C]alanine and l-[3-13C]alanine, followed by an analysis of the labeling patterns of coproporphyrinogen III using 13C NMR spectroscopy. The results demonstrated that l-alanine was transformed via pyruvic acid to both acetyl-CoA and oxaloacetic acid. Additionally, the quantitative analysis indicated that pyruvic acid was transformed to acetyl-CoA and oxaloacetic acid in the ratio of 1:0.8. 相似文献
103.
Dai Kato Atsumu Oda Mutsuo Tanaka Seiichiro Iijima Tomoyuki Kamata Masami Todokoro Yasuo Yoshimi Osamu Niwa 《Electroanalysis》2014,26(3):618-624
We developed an electrochemical system for detecting lipopolysaccharide (LPS) that uses an ultraflat nanocarbon film electrode modified with poly‐ε‐lysine with a high affinity to LPS. LPS was captured on the modified electrode, and then ferrocene labeled polymyxin B (FcPMB) was captured on the LPS adsorbed electrode via the LPS‐PMB affinity interaction. The adsorbed FcPMB provided an amplified response with Fe2+ ions, and the current response was dependent on the amount of captured LPS (LOD=2.0 ng/mL). This was due to the efficient accumulation of the obtained current for LPS and the very low noise made possible by the ultraflat surface. 相似文献
104.
Shiho Tokonami Keisuke Nishida Yushi Nishimura Shimpei Hidaka Yojiro Yamamoto Hidenobu Nakao Takuya Iida 《Research on Chemical Intermediates》2014,40(6):2337-2346
We investigated the optical response of a huge number of silver nanoparticles (AgNPs) densely assembled on an organic microsphere, i.e., AgNP-fixed bead, under the collective phenomena of localized surface plasmons. For this purpose, various optical properties of such a AgNP-fixed bead were analyzed in aqueous solution by dark-field optical microscopy and laser Raman microscopy. In particular, in comparison with the optical spectrum of single AgNPs, significant spectral broadening and redshift were observed due to plasmonic superradiance with decreasing interparticle distance to the subnanoscale when using small binder molecules in the AgNP-fixed bead. Furthermore, we observed surface-enhanced Raman scattering and clarified the sensitivity of the signal intensity to the size of the binder molecules between the AgNPs, which can be explained based on optical response theory using a discrete integral with spherical cells. These results and discussion provide a guiding principle for broadband plasmonic light absorbers and for highly sensitive detection of small molecules and nanoscale biomaterials based on vast numbers of nanogaps produced by a bottom-up self-assembly process. 相似文献
105.
In our previous paper Ohkuwa et al. (2016) corrigendum was found in Eqs. (3.4) and (3.6). However, conclusions of our previous paper are not changed. 相似文献
106.
We examined the formation of complexes between terbium ion (Tb3+) and carbohydrates labeled with aminobenzene compounds. Of the examined compounds, carbohydrates labeled with 4-aminosalicylic acid showed intense fluorescence with Tb3+ in the presence of cetylpyridinium chloride at pH 6.0. Calibration curves for maltose derivative showed good linearity between 5 pmol and at least 600 pmol, with good reproducibility. We applied the proposed technique to binding studies between manno-oligosaccharides and Concanavalin A. 相似文献
107.
The pendant E-ring moiety of the podophyllotoxin aza-analogue 1 that is a potent inhibitor of microtubule assembly was modified in order to acquire inhibitory activity of DNA topoisomerase II. The monophenolic analogue 2 did not exhibit human topoisomerase II inhibition, while the ortho-quinone 3 that was obtained by oxidation of 2 inhibited its catalytic activity (decatenation) in a dose-dependent manner and stimulated double strand DNA breaks in supercoiled circular plasmid DNA, resulting in the production of linear DNA. These results showed that the topoisomerase II inhibition of the ortho-quinone 3 is due to stabilization of the topoisomerase II-DNA covalent binary complex. On the other hand, the ortho-quinone 3 did not inhibit the relaxation process of supercoiled DNA by topoisomerase I at concentrations up to 400 microM, nor was intercalation observed in unwinding measurements of 3. Therefore, the ortho-quinone 3 was shown to be a novel nonintercalative topoisomerase II specific inhibitor that stabilizes the cleavable complex. The present results suggest that the 4'-free hydroxyl group on the E-ring and the sugar moiety on the C-ring are not a prerequisite for topoisomerase II inhibition by podophyllotoxin derivatives. 相似文献
108.
Kazuo Onda Yasuo Kaga Ken Kato 《Journal of Quantitative Spectroscopy & Radiative Transfer》1983,29(3):277-278
The temperature profile in Fig. 3 of Ref. 1 is better approximated by a relation for a turbulent boundary layer than a laminar boundary layer. The critical Reynolds number is expected to be lowered in the flow train of MHD combustion gas because of large turbulence in the combustor and by roughness along the duct. 相似文献
109.
High Temperature Phosphidation of Iron-Nickel Alloys by Phosphorus Vapor A study was undertaken concerning the products and kinetics in the phosphidation of iron-nickel alloys with various ratios of metallic constituents at 700° in phosphorus vapor at 1 atm by a sealed-tube method. X-ray diffraction patterns and an electron microprobe analysis of the products showed that the phosphide-layer structure reaches the expression of NiP2 ~ Ni6P5/Ni2P, Fe2P/(Fe? Ni alloy). The phosphidations proceeded according to a parabolic rate law for all the compositions of the alloy. A marker experiment indicated that the diffusing species was not phosphorus but metals. The rate constant decreased with an increase in the content of iron in the alloy. 相似文献
110.
Yasuo Tokit Yoshio Inoue Riichir Chûj Yasuhiro Miyoshi 《Magnetic resonance in chemistry : MRC》1975,7(10):485-487
Carbon-13 NMR spectra have been obtained for all-trans-N-retinylidene-n-butylamine as an analogue of the Schiff's base linkage compound in visual pigment. The chemical shift changes on going from all-trans-retinal1 to all-trans-N-retinylidene-n-butylamine are observed. These changes indicate the collapse of the bond alternation in conjugated polyene carbons, whereas N-protonation in all-trans-N-retinylidene-n-butylamine does not affect the bond alternation. 相似文献