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81.
Petrykin V Kakihana M Yoshioka K Sasaki S Ueda Y Tomita K Nakamura Y Shiro M Kudo A 《Inorganic chemistry》2006,45(23):9251-9256
The stable water-soluble tantalum complex with lactic acid (ammonium tetralactatodiperoxo-mu-oxo-ditantalate(V)), (NH4)4[Ta2(C3H4O3)4(O2)2O].3H2O, was prepared in the crystalline form. According to the single-crystal X-ray diffraction data, this compound forms a monoclinic cell with a = 13.85(2) A, b = 9.06(1) A, c = 12.32(2) A, and beta = 116.30 degrees , space group C2 (No. 2), and has Z = 2 molecules per unit cell. The solid-state 13C NMR data and low flack parameter are consistent with the determined structure. Appearance of the same vibration modes in Raman and IR spectra supports the choice of the space group without inversion symmetry. The solution of the tantalum complex was successfully applied for the synthesis of two photocatalytic materials, NaTaO3 and Sr2Ta2O7. 相似文献
82.
83.
84.
Incednine is a 24-membered macrolactam antibiotic produced by Streptomyces sp. ML694-90F3. A previous study demonstrated that its unique nitrogen-containing starter unit was derived from l-glutamate. To elucidate the missing link between l-glutamate and the starter unit, deuterium labeled amino acid feeding experiments were conducted. These experiments revealed that 3-[3-(2)H]aminobutyrate and β-[2,2,4,4-(2)H(4)]glutamate were incorporated into the starter moiety. The results indicate that a novel decarboxylation of β-glutamate to give 3-aminobutyrate is involved in incednine biosynthesis. 相似文献
85.
86.
Nagatomo T. Matsuta K. Hashimoto K. Ota M. Arimura K. Minamisono K. Sumikama T. Ogura M. Iwakoshi T. Miyake T. Kudo S. Akutsu K. Minamisono T. Fukuda M. Mihara M. Momota S. Nojiri Y. Kitagawa A. Torikoshi M. Kanazawa M. Suda M. Hirai M. Symons T. J. M. Krebs G. F. Alonso J. R. Zhu S. Y. Zhu J. Z. Xu Y. J. 《Hyperfine Interactions》2001,136(3-8):233-237
The nuclear spin alignments of the β-emitting fragments 12B(I
π=1+, T
1/2=20.2 ms) and 13B(I
π=3/2−, T
1/2=17.4 ms) produced in the 100A-MeV 13C, 15N + 9Be collisions respectively have been observed for the first time detecting asymmetric β-ray emission from these nuclei. By
means of the spin manipulation technique based on the hyperfine interaction of B isotopes in TiO2, both the polarization P and the alignment A were determined reliably. The obtained P and A were significantly smaller than the expectation from the kinematical model. From the fact that the quenching factors for
P and A are almost the same, there may be some depolarization mechanism in the collision process itself.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
87.
Minamisono T. Matsuta K. Minamisono K. Kudo S. Ogura M. Fukuda S. Sato K. Mihara M. Fukuda M. 《Hyperfine Interactions》2001,136(3-8):225-231
In order to precisely determine the |eqQ(41Sc)/h| of 41Sc(I
π=7/2−, T
1/2=0.596 s) implanted in a TiO2 single crystal the electric field gradient tensor and anisotropic chemical shift were determined by detecting the Fourier
Transformed Pulse-NMR of 45Sc(I
π=7/2−, stable) in the crystal at a high field of 7.0 T and 9.4 T. Combining the new |eqQ(41Sc)/h| value with the Q(45Sc)=−(23.6±0.2) fm2, also renewed by using the known atomic hyperfine interaction constants and Sternheimer polarization effect, the |Q(41Sc;I
π=7/2−,T
1/2=0.596 s)|=(15.6±0.3) fm2 has been precisely determined. The value is compared with the theoretical Q(41Sc) given by a shell model code.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
88.
Kurinomaru T Tomita S Kudo S Ganguli S Nagasaki Y Shiraki K 《Langmuir : the ACS journal of surfaces and colloids》2012,28(9):4334-4338
The development of technology for on/off switching of enzyme activity is expected to expand the applications of enzyme in a wide range of research fields. We have previously developed a complementary polymer pair system (CPPS) that enables the activity of several enzymes to be controlled by a pair of oppositely charged polymers. However, it failed to control the activity of large and unstable α-amylase because the aggregation of the complex between anionic α-amylase and cationic poly(allylamine) (PAA) induced irreversible denaturation of the enzyme. To address this issue, we herein designed and synthesized a cationic copolymer with a poly(ethylene glycol) backbone, poly(N,N-diethylaminoethyl methacrylate)-block-poly(ethylene glycol) (PEAMA-b-PEG). In contrast to PAA, α-amylase and β-galactosidase were inactivated by PEAMA-b-PEG with the formation of soluble complexes. The enzyme/PEAMA-b-PEG complexes were then successfully recovered from the complex by the addition of anionic poly(acrylic acid) (PAAc). Thus, dispersion of the complex by PEG segment in PEAMA-b-PEG clearly plays a crucial role for regulating the activities of these enzymes, suggesting that PEGylated charged polymer is a new candidate for CPPS for large and unstable enzymes. 相似文献
89.
K. Shikano K. Kudo K. Kobayashi 《Journal of Radioanalytical and Nuclear Chemistry》1985,92(2):307-314
Distillation and substoichimetric precipitation for silicon have been developed for the determination of trace amounts of silicon. It is based on substoichiometric precipitation as barium fluorosilicate and the distillation of silicon tetrafluoride. The separation has been applied for the determination of silicon in gallium arsenide and NBS steel as standard reference material. 相似文献
90.
Keigo Okada Makoto Dohi Masahiro Kudo Takuya Miyayama 《Applied Surface Science》2008,255(4):1104-1106
Evaluation of immobilized-proteins on bio-devices is important for the development of sophisticated devices. Lysozyme molecules immobilized on substrates were evaluated by means of time-of-flight secondary ion mass spectrometry (TOF-SIMS). Two types of the lysozyme-immobilized samples were prepared by controlling the binding parts, i.e., the amino groups or carboxyl groups, of the protein. The TOF-SIMS spectra of each sample were analyzed with mutual information to select fragment ions specific to each sample. According to the results, differences between the samples being immobilized in the different ways are suggested, and the surface structure of the lysozyme molecule immobilized at amino groups is determined based on three-dimensional structure of lysozyme in the Protein Data Bank. 相似文献