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681.
Based on our previous work of in‐capillary denaturing polymer electrophoresis, we present a study of RNA molecular separation up to 6.0 kilo nucleotide by pulsed field CE. This is the first systematic investigation of electrophoresis of a larger molecular mass RNA in linear hydroxyethylcellulose (HEC) under pulsed field conditions. The parameters that may influence the separation performance, e.g. gel polymer concentration, modulation depth and pulse frequency, are analyzed in terms of resolution and mobility. For denaturing and separating RNA in the capillary simultaneously, 2 M acetic acid was added into the HEC polymer to serve as separation buffer. Result shows that (i) in pulsed field conditions, RNA separation can be achieved in a wide range of concentration of HEC polymer, and RNA fragments between 0.3 and 0.6 kilo nucleotide are sensitive to the polymer concentration; (ii) under certain pulsed field conditions, RNA fragments move linearly as the modulation depth increases; (iii) 12.5 Hz is the resonance frequency for RNA reorientation time and applied frequency. 相似文献
682.
Rosica Petrova Nikolova Keiko Fujiwara Noriaki Nakayama Vladislav Kostov-Kytin 《Solid State Sciences》2009,11(2):382-388
The small-pore zirconosilicate Na2ZrSi2O7·H2O crystallizes in monoclinic system with space group C2/c, a = 5.4715(4); b = 9.4111(6); c = 13.0969(8) Å, β = 92.851(7)°. Its framework consists of layers built of ZrO6 octahedra and SiO4 tetrahedra and forming condensed [Si2O7] pyrogroups by connection. The sodium ions and water molecules are placed in channels set up between the layers. The stoichiometric and structural similarities of the studied phase with anhydrous compounds having general chemical formula A2(3)MT2O7 (A = Na,K; M = Zr,Lu,Sc; T = Si,Ge) are discussed. The topological relationship of their structures is interpreted in the light of spatial combination of silicon and zirconium polyhedra as basic building units into larger composite building units and their three-dimensional arrangement. 相似文献
683.
Masahiro Sadakane Prof. Dr. Keiko Yamagata Katsunori Kodato Keisuke Endo Koshiro Toriumi Prof. Dr. Yoshiki Ozawa Prof. Dr. Tomoji Ozeki Prof. Dr. Takuro Nagai Dr. Yoshio Matsui Dr. Norihito Sakaguchi Prof. Dr. William D. Pyrz Douglas J. Buttrey Prof. Douglas A. Blom Dr. Thomas Vogt Dr. Wataru Ueda Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(21):3782-3786
Mix and match : The pentagonal [Mo6O21]n? polyoxomolybdate building block assembles with other sources of Mo, V, and Sb ions to form an orthorhombic Mo‐V‐Sb oxide. The first single‐crystal X‐ray analysis of an orthorhombic Mo–V‐based oxide, a promising catalyst for light alkane selective oxidation known as the “M1 phase”, revealed the structure of the compound.
684.
685.
Polarized-light induced anisotropy of Disperse Orange 3 (DO3) depending on the polymer matrices was investigated by polarized FTIR spectroscopy. The dynamic behavior of the azo dyes doped in a series of methacrylate polymers was analyzed in terms of the orientation factors. Two factors, the free volume and the local polarity of matrices, are found to govern the dynamic behavior of DO3. It was found that induced anisotropy for trans and cis isomers varies depending on Tg of polymer matrix. Further, the thermal isomerization rate depend on the isomerization mode which is governed by the matrix polarity. The branched-alkyl chains are considered to block the interaction between ester groups and DO3 and introduce the DO3 molecules into the less polar environment. 相似文献
686.