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101.
作者在《数学学报》(2016, {\bf 59}(4))上的一篇文章中, 给出了几个$l^{0}$型赋$F$-范空间的共轭空间的表示定理. 对于赋范空间序列$\{X_{i}\}$,本文研究$l^{0}(\{X_{i}\})$型赋$F$- 范空间的共轭空间的表示问题,得到代数表示连等式$\left(l^{0}(\{X_{i}\})\right)^{*}\stackrel{A}{=}\left(c^{0}_{00}(\{X_{i}\})\right)^{*}\stackrel{A}{=}c_{00}(\{X^{*}_{i}\})$,$$\left(l^{0}(X)\right)^{*}\stackrel{\mathrm{A}}{=}\left(c^{0}(X)\right)^{*}\stackrel{\mathrm{A}}{=}\left(c_{0}^{0}(X)\right)^{*}\stackrel{\mathrm{A}}{=}\left(c^{0}_{00}(X)\right)^{*}\stackrel{\mathrm{A}}{=}c_{00}(X^{*}),$$以及序列弱星拓扑下的拓扑表示定理$\left(c^{0}_{00}(\{X^{*}_{i}\}),sw^{*}\right)=c^{0}_{00}(\{X^{*}_{i}\})$. 对于内积空间序列与通常拓扑下的数域空间序列,文章最后给出了基本表示定理的具体表现形式.  相似文献   
102.
Reactions of Hpymtza [Hpymtza = 5‐(2‐pyrimidyl)tetrazole‐1‐acetic acid] with MnCl2 · 4H2O under different pH conditions, afforded the complexes [Mn(pymtza)2(H2O)4] ( 1 ) and [Mn2(pymtza)2Cl2(EtOH)] · H2O ( 2 ). The compounds were structurally characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. Compound 1 shows a mononuclear structure, whereas complex 2 has a 1D chain structure. In compound 1 , the pymtza ligand only acts in a monodentate manner to coordinate to one central MnII atom by one carboxylate atom, In 2 , pymtza acts as tetradentate ligand to connect three MnII ions. Compounds 1 and 2 display 3D networks by hydrogen bonding interactions. Furthermore, the luminescence properties of Hpymtza as well as compounds 1 and 2 were investigated at room temperature in the solid state.  相似文献   
103.
We prove new composition theorems for Stepanov-like almost automorphic and Stepanov-like pseudo-almost automorphic functions. An application is given to a class of evolution equations with Stepanov-like pseudo-almost automorphic perturbations.  相似文献   
104.
王慧  许玉宇  王国新  刘烽  吴骋 《光谱实验室》2011,28(5):2260-2263
采用浓盐酸溶解样品,电感耦合等离子体-原子发射光谱法测定铁矿中的铅元素含量,方法检出限为0.001%.对有证标准物质进行分析,测定值与证书值吻合,相对标准偏差为1.99%-2.21%.  相似文献   
105.
A biosensor based on hemoglobin‐Fe3O4@SiO2 nanoparticle bioconjunctions modified indium‐tin‐oxide (Hb/Fe3O4@SiO2/ITO) electrode was fabricated to determine the concentration of H2O2. UV‐vis absorption spectra, fourier transform infrared (FT‐IR) spectroscopy, cyclic voltammetry (CV) and high‐resolution transmission electron microscopy (HRTEM) were used to characterize the bioconjunction of Fe3O4@SiO2 with Hb. Experimental results demonstrate that the immobilized Hb on the Fe3O4@SiO2 matrix retained its native structure well. In addition, Fe3O4@SiO2 nanoparticles (NPs) are very effective in facilitating electron transfer of the immobilized enzyme, which can be attributed to the unique nanostructure and larger surface area of the Fe3O4@SiO2 NPs. The biosensor displayed good performance for the detection of H2O2 with a wide linear range from 2.03×10?6 to 4.05×10?3 mol/L and a detection limit of 0.32 µmol/L. The resulting biosensor exhibited fast amperometric response, good stability, reproducibility, and selectivity to H2O2.  相似文献   
106.
Reactions of CdX2(X=NO3-, ClO4-) with Hatza (atza=5-aminotetrazole-1-acetato anion) and 2,2′-bipyridine (2,2′-bipy) or 1,10-phenanthroline (1,10-phen) in a methanol/aqueous solution produced a set of new Cd(Ⅱ) coordination polymers, {[Cd(atza)(H2O)(2,2′-bipy)]ClO4}n (1), {[Cd(atza)(H2O)(1,10-phen)]ClO4 }n (2), {[Cd(atza)(H2O)(2,2′-bipy)]NO3}n (3) and {[Cd(atza)2 (1,10-phen)]·0.5H2O}n (4). Single-crystal X-ray diffraction analysis reveals that each Cd(Ⅱ) ion has a distorted octahedral coordination geometry in 1-4, and the Cd(Ⅱ) ion centers are connected through the tridentate atza bridging ligands to form a 2D layer (1-3) or ID chain (4) structure. The fluorescent properties of 2 and 4 are also discussed.  相似文献   
107.
Three new metal(II) 2-pyrazinephosphonates have been synthesized by hydrothermal reactions based on 2-pyrazinephosphonic acid (C(4)H(3)N(2)PO(3)H(2)1) as ligand, namely, Zn(C(4)H(3)N(2)PO(3)) (2), Cd[(C(4)H(3)N(2)PO(3))(H(2)O)] (3) and Cd[(C(4)H(3)N(2)PO(3)H)Cl]·H(2)O (4). In compound 2, the O-P-O bridged inorganic layers are pillared by pyrazinyl groups into a three-dimensional network. In compound 3, the {CdO(5)N} and {CPO(3)} polyhedra are interconnected via edge and corner-sharing into a metal phosphonate layer. In compound 4, the {Cd(2)Cl(2)} dimers are linked by O-P-O bridges into a one-dimensional double chain, and the chains are joined into a layer by pyrazinyl groups. Here we employ pyrazinephosphonic acids as structure directing motifs to form extended structures and materials with interesting luminescent properties. The luminescent properties studied have also been described.  相似文献   
108.
陶永梅  林林  董帅  刘俊明 《中国物理 B》2012,21(10):107502-107502
The semi-quantum two-orbital exchange model is used to investigate the effect of small rare-earth ion substitution on orthorhombic RMnO 3 with A-type antiferromagnetic order,using the Monte Carlo algorithm,exact diagonalization,and zero-temperature optimization approaches.It is revealed that the substitution results in a rich multiferroic phase diagram where the coexisting A-type antiferromagnetic phase and spiral spin phase,pure spiral spin phase,coexisting spiral spin phase,the E-type antiferromagnetic phase,and the pure E-type antiferromagnetic phase emerge in sequence.The multiferroic phase transitions modulate substantially the electric polarization,which is consistent qualitatively with recent experiments.  相似文献   
109.
总部薪酬激励与内部资本市场配置效率   总被引:1,自引:0,他引:1  
在内部资本市场代理理论的框架下,以非线性规划的库恩-塔克定理为主要工具,探讨了总部薪酬激励机制在内部资本市场配置中的关键影响.假定股权收益和私人投资收益是总部薪酬的主体,分部间的投资额取决于总部对股权收益和私人投资收益的权衡,这种权衡导致了内部资本市场的"平均主义".更进一步,投资总量内生时,追求股权收益和私人投资收益最大化,总部倾向于在各分部过度投资.  相似文献   
110.
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