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81.
Reduced molybdoantimonylphosphoric acid is extracted into di-isobutyl ketone (DIBK) and phosphorus in the extract is indirectly determined by inductively-coupled plasma emission spectrometric measurement of the Mo II 202.03-nm or Sb I 206.83-nm line. Washing of the extract with acid is unnecessary because of the low solubility of DIBK in water. Arsenic(III), Si, Ge, Fe(III) and most anions do not cause serious interference but arsenic(V) must be absent. The detection limits are 5.2 and 45 pg P ml-1, and the relative standard deviations for 1 μg of phosphorus are 2.0% and 2.5%, for molybdenum and antimony measurements, respectively. The method is applied in the analysis of river and seawater. 相似文献
82.
Masao Shiozaki Yukiko Watanabe Toshio Kaneko Daisuke Tanaka Shin-ichi Kurakata 《Tetrahedron》2005,61(21):5101-5122
Lipid A analogues containing glucose in substitution for glucosamine on the reducing end were synthesized, and the inhibitory activities on LPS-induced TNFα production (LPS-antagonistic activity) in vitro using human whole blood cells were measured. The IC50 values (nM) of these ten compounds, 8, 14, 21, 31, 40, 51, 57, 62, 67 and 72, were 11.2, 15.4, 2.7, 0.1, 0.4, 1.3, 3.2, 3.2, 1.4 and 14.4, respectively. And also inhibitory activities (ID50) on TNFα production toward galactosamine loaded C3H/HeN mice in vivo of compounds 21, 31, 57, 62 and 67 were measured. The values of these compounds were 0.29, 0.50, 0.61, not dose-dependent and 0.33 mg/kg, respectively. 相似文献
83.
Yamagami C Hamasaki A Kumagai Y Moritoki T Tanahashi T 《Chemical & pharmaceutical bulletin》2005,53(4):398-401
We recently proposed a new hydrogen-accepting scale, S(HA), on the basis of the heat of formation calculated by the conductor-like screening model (COSMO) method. In this work, the same approach was applied to a series of compounds with a common hydrogen-donor group. Thus the S(HA) values for monosubstituted phenols were calculated and used for correlating their log P(oct) values (P(oct): 1-octanol/water partition coefficient) with log P(CL) (P(CL): chloroform/water partition coefficient) and log P(E) (P(E): butyl ether/water partition coefficient). It was demonstrated that the S(HA) parameter works effectively, providing excellent correlations whose physicochemical meanings are well rationalized in terms of hydrogen-bonding characteristics of the substituents. 相似文献
84.
Tin chlorides, SnCl2 and SnCl4.5H2O are excellent catalysts for the reactions of trioses, dihydroxyacetone and glyceraldehyde with alcohols (MeOH, EtOH and nBuOH) to give alkyl lactates, whose reaction mechanism involves the intermediary formation of pyruvic aldehyde followed by its esterification, which is distinctively promoted by tin halides. 相似文献
85.
Yoshimi Akiyama 《Nuclear Physics A》1985,433(3):369-382
Basic properties of the interacting boson model with s-, d- and g-bosons are investigated in rotational nuclei. An SU(3)-seniority scheme is found for the classification of physically important states according to a group reduction chain U(15) ? SU(3). The capability of describing rotational bands increases enormously in comparison with the ordinary sd interacting boson model. The sdg boson model is shown to be able to describe the so-called anharmonicity effect recently observed in the 168Er nucleus. 相似文献
86.
M. Mihara T. Izumikawa H. Ueno K. Matsuta D. Nishimura T. Nagatomo T. Moriguchi Y. Ito D. Nagae M. Fukuda A. Yoshimi K. Yamada M. Takechi Y. Ichikawa S. Momota Y. Hirayama T. Ohtsubo S. Suzuki T. Kubo Y. Namiki A. Ozawa Y. Ishibashi H. Oishi K. Suzuki I. Hachiuma K. Namihira D. Horikawa T. Minamisono T. Yamaguchi T. Kuboki T. Suzuki K. Satoh Y. Kobayashi K. Asahi K. Matsukawa K. Shirai 《Hyperfine Interactions》2010,197(1-3):143-147
The β-NMR study of short-lived nucleus 58Cu (I π ?=?1?+?, T 1/2?=?3.2 s) in Si has been performed. Spin polarization of 58Cu induced by the charge exchange reaction of 58Ni was observed in Si at 15 K. The 58Cu magnetic moment $|\upmu[^{58}\mbox{Cu}]| = (0.46 \pm 0.03)\upmu_{\rm N}$ deduced from the β-NMR spectrum is consistent with the previous results on the laser spectroscopy. The present result shows that the 58Cu nucleus is promising as a new nuclear probe for the microscopic study of Cu impurities in Si. 相似文献
87.
T. Nagatomo H. Ueno M. Mihara K. Matsuta A. Yoshimi Y. Ichikawa K. Yamada H. Kawamura A. Ozawa T. Moriguchi Y. Ishibashi K. Asahi M. Uchida K. Suzuki T. Inoue Y. Hasama H. Iijima T. Sumikama M. Fukuda T. Minamisono 《Hyperfine Interactions》2010,198(1-3):103-107
Electric quadrupole coupling constant eqQ/h of the extremely proton-rich 23Al (I π ?=?5/2?+?, T 1/2?=?0.47 s) nucleus implanted into an Al2O3 single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method (β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as |eqQ/h(23Al) |?=?2.66±0.77 MHz. Using the quadrupole coupling constant of 27Al in Al2O3 as a reference, the Q moment of the ground state of 23Al was extracted as |Q(23Al)|?~?160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction. 相似文献
88.
Hisakazu OGITA Yoshiyuki RIKITAKE Jun MIYOSHI Yoshimi TAKAI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(6):621-629
Nectins have recently been identified as new cell adhesion molecules (CAMs) consisting of four members. They show immunoglobulin-like structures and exclusively localize at adherens junctions (AJs) between two neighboring cells. During the formation of cell–cell junctions, nectins function in cooperation with or independently of cadherins, major CAMs at AJs. Similar to cadherins, which are linked to the actin cytoskeleton by binding to catenins, nectins also bind to afadin through their C-terminal region and are linked to the actin cytoskeleton. In addition to nectins, there are nectin-like molecules (Necls), which resemble nectins in their structures and consist of five members. Nectins and Necls are involved in the formation of various kinds of cell–cell adhesion, and also play key roles in diverse cellular functions including cell movement, proliferation, survival, and differentiation. Thus, nectins and Necls are crucial for physiology and pathology of multicellular organisms. 相似文献
89.
Shiro Aizawa Etsuro Yoshimura Miwako Hamachi Hiroki Haraguchi Yukiko Dokiya Keiichiro Fuwa 《光谱学快报》2013,46(4):191-202
Flame emission determination of Sr in sea water is studied using an ordinary atomic absorption apparatus. The analytical line 4607 A is used with background correction at 4616 A. The ionization is found to be negligible in air acetylene flame with sea water, and the interference of H2SO4 is elimentated using the higher part of the flame. 相似文献
90.
Takahiro Yonezawa Tatsuya Murakami Koichi Higashimine Antoine Fleurence Yoshifumi Oshima Yukiko Yamada-Takamura 《Surface and interface analysis : SIA》2019,51(1):95-99
Layered materials can be grown on various substrates through van der Waals epitaxy (vdWE) regardless of lattice mismatch. The atomistic study of the film-substrate interface in vdWE is becoming increasingly important due to their expected applications as two-dimensional (2D) materials. In this contribution, we have grown GaSe thin films on Ge(111) substrates by molecular beam epitaxy and studied the GaSe/Ge(111) interface using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Cross-sectional HAADF-STEM observations revealed that the grown layers adopt predominantly the expected wurtzite-like structure and stacking, but layers with zinc-blende-like structure, similar to Ga2Se3 but apparently different, and other layer stacking sequences, exist locally near the film-substrate interface. These results demonstrate that even in vdWE, structural changes can occur in the grown layers adjacent to the substrate, highlighting the importance of such interface for synthesizing and applying ultimately thin 2D materials. 相似文献