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981.
Jia‐Jia Wei Na Zhang Yu‐Ling Wang Qing‐Yan Liu 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):m145-m148
The asymmetric unit of the title compound, [InNa(C3H5O3)4]n, consists of one InIII ion, one NaI ion and four crystallographically independent l ‐lactate monoanions. The coordination of the InIII ion is composed of five carboxylate O and two hydroxy O atoms in a distorted pentagonal–bipyramidal coordination geometry. The NaI ion is six‐coordinated by four carboxylate O atoms and two hydroxy O atoms from four l ‐lactate ligands in a distorted octahedral geometry. Each InIII ion is coordinated by four surrounding l ‐lactate ligands to form an [In(l ‐lactate)4]− unit, which is further linked by NaI ions through Na—O bonds to give a two‐dimensional layered structure. Hydrogen bonds between the hydroxy groups and carboxylate O atoms are observed between neighbouring layers. 相似文献
982.
983.
从迭代数列及其基本性质出发,给出单调有界定理、压缩映象原理、Cauchy收敛准则和上(下)极限四种判别迭代数列收敛的方法. 相似文献
984.
We investigate the Morita context and graded cases for weak group corings and derive some equivalent conditions for μ to be
surjective. Furthermore, we develop Galois theory for weak group corings. As an application, we give Galois theory for comodulelike
algebras over a weak Hopf group coalgebra. 相似文献
985.
This paper mainly concerns a tuple of multiplication operators
defined on the weighted and unweighted multi-variable Bergman
spaces, their joint reducing subspaces and the von Neumann algebra
generated by the orthogonal projections onto these subspaces. It is
found that the weights play an important role in the structures of
lattices of joint reducing subspaces and of associated von Neumann
algebras. Also, a class of special weights is taken into account.
Under a mild condition it is proved that if those multiplication
operators are defined by the same symbols, then the corresponding
von Neumann algebras are $*$-isomorphic to the one defined on the
unweighted Bergman space. 相似文献
986.
为了研究重复冲击载荷作用下泡沫金属夹芯梁的动态响应,采用Abaqus数值仿真软件,基于可压碎泡沫模型(crushable foam),建立了泡沫金属夹芯梁遭受楔形质量块冲击的有限元模型。通过将仿真获得的夹芯梁上下面板最终挠度与重复冲击实验结果进行对比,验证仿真方法的准确性。在此基础之上,分析了泡沫金属夹芯梁在楔形质量块重复冲击作用下的变形模式、加卸载过程以及能量耗散特性。结果表明,在重复冲击载荷作用下,夹芯梁的变形不断累积,上面板主要出现局部凹陷和整体弯曲,而芯层则是局部压缩,下面板表现为整体弯曲。在重复加卸载过程中,加卸载刚度随着冲击次数的增加而增大。随着冲击次数的增加,上面板和芯层的能量吸收增量不断减小,而下面板的能量吸收增量不断增加,且最终均趋于稳定。泡沫金属夹芯梁的塑性变形能增量不断减小,而回弹系数随着冲击次数逐渐增加,最后趋于稳定值。 相似文献
987.
A new image fusion encryption algorithm based on image fusion and DNA sequence operation and hyper-chaotic system is presented. Firstly, two DNA sequences matrices are obtained by encoding the original image and the key image. Secondly, using the chaotic sequences generated by Chen's hyper-chaotic maps to scramble the locations of elements from the DNA sequence matrix which generated form original image. Thirdly, XOR the scrambled DNA matrix and the random DNA matrix by using DNA sequence addition operation. At last, decoding the DNA sequence matrix, we will get the encrypted image. The simulation experimental results and security analysis show that our algorithm not only has good encryption effect, but also has the ability of resisting exhaustive attack and statistical attack. 相似文献
988.
Jiyu Fan Langsheng Ling Bo Hong Wei Tong Lei Zhang Yangguang Shi Weichun Zhang Yan Zhu Dazhi Hu Yao Ying Li Pi Yuheng Zhang 《Applied Physics A: Materials Science & Processing》2013,112(2):397-402
In this paper, we present the investigations of electron paramagnetic resonance on perovskite manganite Pr0.5Sr0.5MnO3 and Ga-doped Pr0.5Sr0.5Mn0.95Ga0.05O3. The temperature dependent paramagnetic resonance spectra parameters (effective g-factor, peak-to-peak linewidth ΔH pp and double integrated intensities) have been used to study the paramagnetic spin correlations and spin dynamics. The gradual increase of effective g-factor is attributed to the presence of orbital ordering above T C. The model fittings of temperature dependent double integrated intensities reveal Arrhenius law is appropriate for describing Pr0.5Sr0.5Mn0.95Ga0.05O3 instead of Pr0.5Sr0.5MnO3 system. As for Pr0.5Sr0.5MnO3, the broadening of linewidth with the temperature increase origins from the contribution of small polaron hopping in the PM regime. However, as for Pr0.5Sr0.5Mn0.95Ga0.05O3, the broadening of EPR linewidth can be understood with the spin-lattice relaxation mechanism. 相似文献
989.
Ming‐Zheng Wang Feng‐Xia Liang Biao Nie Long‐Hui Zeng Ling‐Xia Zheng Peng Lv Yong‐Qiang Yu Chao Xie Yang Yang Li Lin‐Bao Luo 《Particle & Particle Systems Characterization》2013,30(7):630-636
Schottky junctions made from a titanium dioxide nanotube (TiO2NT) array in contact with a monolayer graphene (MLG) film are fabricated and utilized for UV light detection. The TiO2NT array is synthesized by the anodization and the MLG through a simple chemical vapor deposition process. Photoconductive analysis shows that the fabricated Schottky junction photodetector (PD) is sensitive to UV light illumination with good stability and reproducibility. The corresponding responsivity (R), photoconductive gain (G), and detectivity (D*) are calculated to be 15 A W?1, 51, and 1.5 × 1012 cm Hz1/2 W?1, respectively. It is observed that the fabricated PD exhibits spectral sensitivity and a simple power‐law dependence on light intensity. Moreover, the height of the Schottky junction diode is derived to be 0.59 V by using a low temperature I–V measurement. Finally, the working mechanism of the TiO2NT array/MLG film Schottky junction PD is elucidated. 相似文献
990.
"M+N"理论从误差理论的角度阐明了光谱分析中外界干扰因素即"N"因素对于测量精度的影响,并给出了提高测量精度的方法。通过采用实测变电压光源光谱数据与多组分线性吸收谱仿真模型相结合的方法,构造了三组分的理想混合溶液并选择光源电压作为影响被测组分浓度测量精度的"N"因素,分别设定了不同信噪比下的两组各三种不同的校正集与预测集样本"N"因素分布方式,得出了对于系统误差类"N"因素而言,校正集与预测集的"N"因素分布范围对组分浓度的预测精度具有一定影响的结论。实验结果验证了"M+N"理论中"N"因素用于提高测量精度的可行性,同时为其他测量系统减小外界干扰提高测量精度提供了理论指导。 相似文献