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131.
Summary The silica-supported comb-shaped polymer (Sil-ODA18) with a “crystalline-to-isotropic” phase transition showed the characteristic behaviors of both polymeric and monomeric ODS
phases. This was examined using a SRM 869 test mixture. Furthermore, Sil-ODA18 exhibited a specific selectivity towards the critical pairs of polycyclic aromatic hydrocarbons (PAHs), such as acenaphthene
and fluorene, or benz(a)anthracene and chrysene, or benzo(ghi)perylene, indeno(1,2,3-cd)pyrene and dibenz(a,h)anthracene.
The separation of these solutes was controlled by selecting temperature and solvent systems. The selectivity on Sil-ODA18 was also compared with a conventional ODS (octadecylsilyl silica gel) column. The selectivity on a Sil-ODA18 matrix is attributable to an orientation change of the long-chain alkyl substituents on the surface of the silica base material
on transition from crystalline to isotropic state. 相似文献
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T. Shimoda K. Tajiri K. Kura A. Odahara M. Suga Y. Hirayama N. Imai H. Miyatake M. Pearson C. D. P. Levy K. P. Jackson R. Legillon C. Petrache T. Fukuchi N. Hamatani T. Hori M. Kazato Y. Kenmoku T. Masue H. Nishibata T. Suzuki A. Takashima R. Yokoyama 《Hyperfine Interactions》2014,225(1-3):183-191
Spin-polarized radioactive nuclear beams at TRIUMF enable a new spectroscopic method which efficiently assigns spins and parities of the daughter levels by taking advantage of the asymmetric β-decay of the polarized parent nucleus. This method was successfully applied to structure studies of 29Mg and 30Mg in connection with the physics of the “island of inversion”. In 29Mg, two low-lying levels with intruder configuration were assigned. In 30Mg, coexistence of spherical shape, prolate shape and γ-collectivity was strongly suggested. 相似文献
136.
We investigate low-frequency electron spin dynamics in a quantum Hall system with wire confinement by nuclear spin relaxation measurements. We developed a technique to measure the local nuclear spin relaxation rate T(1)(-1). T(1)(-1) is enhanced on both sides of the local filling factor ν(wire)=1, reflecting low-frequency fluctuations of electron spins associated with Skyrmions inside the wire. As the wire width is decreased, the fast nuclear spin relaxation is suppressed in a certain range of Skyrmion density. This suggests that the multi-Skyrmion state is modified and the low-frequency spin fluctuations are suppressed by the wire confinement. 相似文献
137.
Systematic Control of the Excited‐State Dynamics and Carrier‐Transport Properties of Functionalized Benzo[ghi]perylene and Coronene Derivatives 下载免费PDF全文
Sunao Hirayama Dr. Hayato Sakai Prof. Yasuyuki Araki Minako Tanaka Masaki Imakawa Prof. Takehiko Wada Prof. Taishi Takenobu Prof. Taku Hasobe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):9081-9093
A series of benzo[ghi]perylene (Bp) and coronene (Cor) derivatives substituted with electron‐withdrawing methoxycarbonyl (COOMe) or electron‐donating methoxyl (MeO) groups was synthesized. The electrochemical, spectroscopic, and photophysical properties of these compounds were investigated by cyclic voltammetry, steady‐state and time‐resolved spectroscopy, and quantum‐yield measurements. Introduction of suitable substituents onto the aromatic rings enabled control of electrochemical and spectroscopic behavior. Examination of excited‐state dynamics revealed that fluorescence quantum yields increased with increasing number of COOMe groups in both Bp and Cor derivatives, consistent with the findings of DFT calculations. Single‐crystal analysis allowed the performance of field‐effect transistors containing single crystals of the derivatives to be rationalized. 相似文献
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C Hirayama M Sakata Y Ohkura H Ihara K Ohkuma 《Chemical & pharmaceutical bulletin》1992,40(8):2106-2109
Attempts were made to prepare adsorbents having a high affinity for endotoxin in the culture supernatant of Bordetella pertussis. When poly(gamma-methyl L-glutamate) (PMLG) was used as a matrix and amino groups as the ligand, the highest affinity for endotoxin was attained even at a high ionic strength (mu = 0.2-0.4). PMLG beads containing amino groups of about 3.2 meq/g selectively removed endotoxin from the culture supernatant of B. pertussis without affecting the protective antigens. It was demonstrated that 1 ml of the wet adsorbent adsorbed 4.5 mg of endotoxin. The beads of PMLG derivatives, therefore, are considered to be a useful adsorbent for the removal of endotoxin from the pertussis vaccine, affecting neither filamentous hemagglutinin nor pertussis toxin. 相似文献