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991.
992.
993.
We developed a facile method of enzyme-mediated conversion of 6-tuliposide to α-methylene-γ-butyrolactone (tulipalin). We used a tuliposide-converting enzyme for the conversion of 6-tuliposides extracted from tulip tissues into the corresponding tulipalins in high yields within 2 h at pH 7.0. The resulting tulipalins were selectively extracted by using several organic solvents. 相似文献
994.
Hiromitsu Kiriyama Michiaki Mori Yoshiki Nakai Takuya Shimomura Manabu Tanoue Atushi Akutsu Hajime Okada Tomohiro Motomura Shuji Kondo Shuhei Kanazawa Akito Sagisaka Jinglong Ma Izuru Daito Hideyuki Kotaki Hiroyuki Daido Sergei Bulanov Toyoaki Kimura Toshiki Tajima 《Optics Communications》2009,282(4):625-2346
We demonstrate a high-contrast, high-intensity double chirped-pulse amplification (CPA) Ti:sapphire laser system using an optical parametric chirped-pulse (OPCPA) pre- amplifier. By injecting cleaned microjoule seed pulses into the OPCPA, a temporal contrast greater than 1010 within picosecond times before the main femtosecond pulse is demonstrated with an output pulse energy of 1.7 J and a pulse duration of 30 fs, corresponding to a peak power of 60 TW at a 10 Hz repetition rate. This system uses a cryogenically-cooled Ti:sapphire final amplifier and generates focused peak intensities in excess of 1020 W/cm2. 相似文献
995.
In this article, we consider the maximum cocliques of the 211: M24 ‐graph Λ. We show that the maximum cocliques of size 24 of Λ can be obtained from two Hadamard matrices of size 24, and that there are exactly two maximum cocliques up to equivalence. We verify that the two nonisomorphic designs with parameters 5‐(24,9,6) can be constructed from the maximum cocliques of Λ, and that these designs are isomorphic to the support designs of minimum weights of the ternary extended quadratic residue and Pless symmetry [24,12,9] codes. Further, we give a new construction of Λ from these 5‐(24,9,6) designs. © 2009 Wiley Periodicals, Inc. J Combin Designs 17: 323–332, 2009 相似文献
996.
997.
Hiroyuki Kamano 《中国物理C(英文版)》2009,33(12)
We present an overview of a research program for the excited nucleon states in Excited Baryon Analysis Center (EBAC) at Jefferson Lab. Current status of our analysis of the meson production reactions based on the unitary dynamical coupled-channels model is summarized, and the N~* pole positions extracted from the constructed scattering amplitudes are presented. Our plans for future developments are also discussed. 相似文献
998.
Hiroyuki Ishibashi 《Czechoslovak Mathematical Journal》2006,56(2):533-541
We define a linear map called a semiinvolution as a generalization of an involution, and show that any nilpotent linear endomorphism
is a product of an involution and a semiinvolution. We also give a new proof for Djocović’s theorem on a product of two involutions. 相似文献
999.
Toshifumi Satoh Masaki Tamaki Yoshikazu Kitajyo Takahiro Maeda Hiroyuki Ishihara Tomoko Imai Harumi Kaga Toyoji Kakuchi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):406-413
A novel biodegradable unimolecular reversed micelle consisting of a poly(L ‐lactide) (PLA) shell and a hyperbranched D ‐mannan (HBM) core, that is, a chestnut‐shaped polymer (PLA–HBM), was synthesized by the polymerization of L ‐lactide on HBM with 4‐(dimethylamino)pyridine (DMAP) as the catalyst. The obtained polymers were soluble in dimethyl sulfoxide, tetrahydrofuran, and chloroform but insoluble in H2O. The molecular weights of the PLA chain on PLA–HBM tended to increase with increasing polymerization time. The number of PLA chains on PLA–HBM could be controlled by the ratio of DMAP to the sugar unit in HBM. The obtained copolymer, PLA–HBM, acted as a unimolecular reversed micelle with an encapsulation ability toward the hydrophilic molecule. In addition, the entrapped hydrophilic molecules were slowly released from the core of PLA–HBM, and the release rate was accelerated by the breaking of the PLA chains of the shell when proteinase K as a hydrolase of PLA was used. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 406–413, 2006 相似文献