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101.
A diamond-like carbon (DLC) coated quartz glass sample holder is used in a portable total reflection X-ray fluorescence (TXRF) spectrometer. A spot area of a water sample on the DLC sample holder becomes smaller than that on a quartz glass sample holder usually used in TXRF analysis because DLC is more hydrophobic. Therefore, the use of the DLC sample holder enhances fluorescent X-rays reaching a detector compared with the use of a quartz glass sample holder, leading to improvement in detection sensitivity. A detection limit of 28 pg is achieved for Cr in a river water sample when using the DLC sample holder. 相似文献
102.
Yasuhiro Masuda Koichiro Asahi Kichiji Hatanaka Sun-Chan Jeong Shinsuke Kawasaki Ryohei Matsumiya Kensaku Matsuta Mototsugu Mihara Yutaka Watanabe 《Physics letters. A》2012
A neutron EDM measurement with a comagnetometer is discussed. For magnetometry, polarized xenon atoms are injected into a cylindrical cell where a cylindrically symmetric magnetic field and an electric field are applied for the EDM measurement. The geometric phase effect (GPE), which originates from particle motion in a magnetic field gradient, is analyzed in terms of the Dyson series. The motion of the xenon atom is largely suppressed because of a small mean free path. The field gradient is controlled by means of NMR measurements, where the false effect of Earth?s rotation is removed. As a result, the GPE is reduced below 10−28e cm. 相似文献
103.
Masuda Y Hatanaka K Jeong SC Kawasaki S Matsumiya R Matsuta K Mihara M Watanabe Y 《Physical review letters》2012,108(13):134801
For the production of high-density ultracold neutrons (UCNs), we placed 0.8 K superfluid helium in a cold neutron moderator. We resolved previous heat-load problems in the spallation neutron source that were particularly serious below 1 K. With a proton-beam power of 400 MeV×1 μA, a UCN production rate of 4 UCN cm(-3) s(-1) at the maximum UCN energy of E(c)=210 neV and a storage lifetime of 81 s were obtained. A cryogenic test showed that the production rate can be increased by a factor of 10 with the same storage lifetime by increasing the proton-beam power as well as (3)He pumping speed. 相似文献
104.
Ohtsuka K Sato S Sato Y Sota K Ohzawa S Matsuda T Takemoto K Takamune N Juskowiak B Nagai T Takenaka S 《Chemical communications (Cambridge, England)》2012,48(39):4740-4742
When a biotinylated FRET probe based on a peptide-thrombin binding aptamer conjugate was introduced together with streptavidin and biotinylated nuclear export signal peptide into HeLa cells, the resulting ternary complex enabled visualization of K(+) concentration changes in the cell. 相似文献
105.
Shinya Miyajima 《Journal of Computational and Applied Mathematics》2012,236(9):2545-2552
An algorithm for enclosing all eigenvalues in generalized eigenvalue problem Ax=λBx is proposed. This algorithm is applicable even if A∈Cn×n is not Hermitian and/or B∈Cn×n is not Hermitian positive definite, and supplies nerror bounds while the algorithm previously developed by the author supplies a single error bound. It is proved that the error bounds obtained by the proposed algorithm are equal or smaller than that by the previous algorithm. Computational cost for the proposed algorithm is similar to that for the previous algorithm. Numerical results show the property of the proposed algorithm. 相似文献
106.
Kensuke Naka Shinsuke Inagi Yoshiki Chujo 《Macromolecular rapid communications》2006,27(24):2113-2117
Summary: The first π‐conjugated poly(thioketene dimer) was synthesized via the homopolymerization of a silylthioketene dimer by a chemical oxidation‐reduction process. The polymerization of trimethylsilylthioketene dimer in the presence of FeCl3 (in CHCl3 at 70 °C for 24 h) gave the corresponding doped poly(thioketene dimer). After treatment of the doped polymer with an aqueous solution of ammonia, the neutral poly(thioketene dimer) was obtained with an incidental desilylation. The polymer obtained was soluble in DMF and DMSO. From gel permeation chromatographic analysis (DMF, polystyrene standards), the number‐average molecular weight of the polymer was found to be 7 460. The polymer showed low oxidation potentials derived from the thioketene dimer unit. An effective extension of the π‐conjugation was observed in the polymer.
107.
Masaru Yoshida Masaharu Asano Hideki Omichi Masaharu Miyajima Yasuo Takahashi Hidetoshi Yamanaka Noriyuki Yonezawa Ryoichi Katakai 《Macromolecular theory and simulations》1993,2(3):377-384
The loosely cross-linked poly(acryloyl-L -proline methyl ester) gel, which is known as one of the typical thermo-responsive gels, shows a volume transition around approximately 14°C in pure water. This volume transition is shifted to higher temperature by treatment in aqueous sodium dodecyl sulfate (SDS). The analysis of the swelling-temperature curve (frequency distribution) was performed according to a moment analysis, in which the area under the swelling-temperature curve (AUC), mean swelling transition temperature (MSTT) and variance of swelling transition temperature (VSTT) were calculated. It is shown that the apparent volume transition temperature can be estimated from MSTT and that VSTT can be used to characterize the shape of the corresponding curves. 相似文献
108.
109.
110.
Rational Design of [13C,D14]Tert‐butylbenzene as a Scaffold Structure for Designing Long‐lived Hyperpolarized 13C Probes 下载免费PDF全文
Yuki Imakura Dr. Hiroshi Nonaka Dr. Yoichi Takakusagi Prof. Dr. Kazuhiro Ichikawa Nesmine R. Maptue Dr. Alexander M. Funk Prof. Dr. Chalermchai Khemtong Prof. Dr. Shinsuke Sando 《化学:亚洲杂志》2018,13(3):280-283
Dynamic nuclear polarization (DNP) is a technique to polarize the nuclear spin population. As a result of the hyperpolarization, the NMR sensitivity of the nuclei in molecules can be dramatically enhanced. Recent application of the hyperpolarization technique has led to advances in biochemical and molecular studies. A major problem is the short lifetime of the polarized nuclear spin state. Generally, in solution, the polarized nuclear spin state decays to a thermal spin equilibrium, resulting in loss of the enhanced NMR signal. This decay is correlated directly with the spin‐lattice relaxation time T1. Here we report [13C,D14]tert‐butylbenzene as a new scaffold structure for designing hyperpolarized 13C probes. Thanks to the minimized spin‐lattice relaxation (T1) pathways, its water‐soluble derivative showed a remarkably long 13C T1 value and long retention of the hyperpolarized spin state. 相似文献