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911.
912.
G. A. Gusev Zhang Gaobin K. Kobayashi Ksyu Jianhua E. V. Moiseenko N. G. Polukhina T. Saito E. Tao V. A. Tsarev Yan Huang 《Bulletin of the Lebedev Physics Institute》2008,35(8):247-250
The results of the second stage of the RAMBAS (Radiation Mechanism of Biomolecular Asymmetry) experiment on the study of the radiation mechanism of the effect on chiral molecules are presented. The optical activity of samples containing racemic mixtures of amino acid complexes with heavy metals before and after their irradiation with an electron flux from a radioactive source was compared. It was shown that irradiation leads to asymmetric decomposition of amino acid complexes and amino acids themselves and chiral asymmetry formation. These results confirm the conclusions made in the first stage of the RAMBAS experiment and can be essential for solving the problem of the origin of life and the formation of chiral asymmetry of the biosphere. 相似文献
913.
914.
The calcination of a TiO(acac)2/Mn(acac)3/epoxy resin complex under an oxygen atmosphere successfully produced nano-sized TiO2/MnO2/carbon clusters composite material. The surface characterizations of the resulting composites indicate that they are composed of nano-sized particles of TiO2, MnO2 and carbon clusters. ESR spectral examination suggests the possibility of an electron transfer in the process of MnO2 → carbon clusters → TiO2. The visible light-responsive oxidation–reduction function of the composite materials has also been confirmed. 相似文献
915.
Y. J. Uemura L. P. Le G. M. Luke B. J. Sternlieb J. H. Brewer J. Carolan W. Hardy R. Kadono R. F. Kiefl S. R. Kreitzman T. M. Riseman C. L. Seaman J. J. Neumeier M. B. Maple G. Saito H. Yamochi H. Takagi S. Uchida J. Gopalakrishnan M. A. Subramanian A. W. Sleight Gang Xiao 《Hyperfine Interactions》1991,63(1-4):131-137
We update our muon spin relaxation studies of the magnetic field penetration depth which show the correlations betweenT
c and the relaxation rate σ αn
s/m
* (carrier density/effective mass) of hole-doped high-T
c cuprate superconductors (La2, Sr3)CuO4, YBa2Cu3O7 (Y1−xPrx)Ba2Cu3O7, and other double and triple layer systems. These studies are extended to the organic superconductor (BEDT-TTF)2Cu(NCS)2. 相似文献
916.
Reduction of dichlorodiphenylstannane with lithium followed by treatment with methyl iodide gave methyltriphenylstannane, dimethyldiphenylstannane and 1,2‐dimethyldistannane. 1,2‐Dilithiodistannane and triphenylstannyllithium were intermediates of this reaction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
917.
T. Idehara I. Ogawa La Agusu T. Kanemaki S. Mitsudo T. Saito T. Fujiwara H. Takahashi 《International Journal of Infrared and Millimeter Waves》2007,28(6):433-442
Gyrotron FU CW II with an 8 T liquid He free superconducting magnet, the second gyrotron of the THz Gyrotron FU CW Series,
has been constructed and the operation test was successfully carried out. It will be used for enhancing the sensitivity of
600 MHz proton-NMR by use of Dynamic Nuclear Polarization (DNP). The designed operation mode of the gyrotron is TE2,6 at the second harmonic. The corresponding frequency is 394.6 GHz. The real operation frequency is 394.3 GHz at TE06 mode, because of fabrication error of the diameter of the cavity. The operation is in complete CW at the output power of
around 30 W or higher at the TE06 cavity mode. There are many other operation modes at the fundamental and the second harmonic. Typical output power of the
fundamental and the second harmonic are higher than 100 W and 20 W, respectively. The highest frequency observed up to the
present is 443.5 GHz at the second harmonic operation of TE6,5 mode. The measured results are compared with the theoretical consideration. 相似文献
918.
919.
Mino T Saito A Tanaka Y Hasegawa S Sato Y Sakamoto M Fujita T 《The Journal of organic chemistry》2005,70(5):1937-1940
Chiral diaminophosphines 4 were prepared from (S)-prolinol-derived aminophosphine oxide 5 by bromination with ring expansion followed by amination with ring contraction and reduction, using trichlorosilane. In the presence of 4 as a ligand, palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate (11) with a dialkyl malonate-BSA-LiOAc system was successfully carried out with good enantioselectivities (up to 98% ee). 相似文献
920.
The determination of psilocybin was carried out by reversed-phase liquid chromatography (HPLC) with fluorescence (FL) detection. Psilocybin was labeled with 5-dimethylaminonaphthalene-1-[N-(2-aminoethyl)]sulfonamide (DNS-ED) at 60 °C for 4 h in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) as the activation reagent. The resulting derivative was separated on a Mightysil RP-18 GP column (150 mm × 4.6 mm, i.d. 3 μm) with the mixture of 50 mM ammonium acetate (AcONH4) and CH3CN, and detected at 539 nm (excitation at 321 nm). The structure of the derivative was identified by HPLC-ESI-MS. A good linear relation of the calibration curve of psilocybin was observed under the proposed conditions for labeling, separation and detection. The quantification limit was 4.4 ng in 1 mg dried mushroom. The proposed procedure was successfully used for the determination of psilocybin in real samples. The contents of psilocybin in six magic mushrooms by the proposed HPLC-FL method were less than 20.0 ng in 1 mg dried samples. 相似文献