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11.
The self‐assembly of NiCl2·6H2O with a diaminodiamide ligand 4,8‐diazaundecanediamide (L‐2,3,2) gave a [Ni(C9H20N4O2)(Cl)(H2O)] Cl·2H2O ( 1 ). The structure of 1 was characterized by single‐crystal X‐ray diffraction analysis. Structural data for 1 indicate that the Ni(II) is coordinated to two tertiary N atoms, two O atoms, one water and one chloride in a distorted octahedral geometry. Crystal data for 1: orthorhombic, space group P 21nb, a = 9.5796(3) Å, b = 12.3463(4) Å, c = 14.6305(5) Å, Z = 4. Through NH···Cl–Ni (H···Cl 2.42 Å, N···Cl 3.24 Å, NH···Cl 158°) and OH···Cl–Ni contacts (H···Cl 2.36 Å, O···Cl 3.08 Å, OH···Cl 143°), each cationic moiety [Ni(C9H20N4O2) (Cl)(H2O)]+ in 1 is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chainlike structure. Thermogrametric analysis of compound 1 is consistent with the crystallographic observations. The electronic absorption spectrum of Ni(L‐2,3,2)2+ in aqueous solution shows four absorption bands, which are assigned to the 3A2g → 3T2g, 3T2g → 1Eg, 3T2g → 3T1g, and 3A2g → 3T1g transitions of triplet‐ground state, distorted octahedral nickel(II) complex. The cyclic volammetric measurement shows that Ni2+ is more easily reduced than Ni(L‐2,3,2)2+ in aqueous solution. 相似文献
12.
Yeoung-Sheng Wang Jyun-Hong Shen Jhan-Ping Lin Jao-Jia Horng 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1443-1448
The porous, stable zeolite materials impregnated with 1 wt% silver (AgZ) were used as anti-bacterial filters to reduce the bio-aerosols as bacterial counts in the indoor air quality of a medical facility to fulfill the regulation of the Taiwan environmental protection administration. The anti-bacterial efficacies of AgZ reach 99 % after 2 h of air circulation in rooms, and its capacity could be re-generated through heated air at 160 °C. The stability and characteristics of AgZ were analyzed by the transmission electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and zeta-potential. Heat of the endothermic reaction of AgZ was evaluated to be 377–388 J g?1 and was discovered as stable below 300 °C. The analysis results also showed the recovery of second isoelectric points at pH 8.5 of AgZ could represent the ability to adsorb negative charged bio-aerosols as well as anti-bacterial capacity. 相似文献
13.
We consider random d‐regular graphs on N vertices, with degree d at least (log N)4. We prove that the Green's function of the adjacency matrix and the Stieltjes transform of its empirical spectral measure are well approximated by Wigner's semicircle law, down to the optimal scale given by the typical eigenvalue spacing (up to a logarithmic correction). Aside from well‐known consequences for the local eigenvalue distribution, this result implies the complete (isotropic) delocalization of all eigenvectors and a probabilistic version of quantum unique ergodicity.© 2017 Wiley Periodicals, Inc. 相似文献
14.
Chia-Lung Tsai Yow-Jon Lin Jia-Hong Chen Hsing-Cheng Chang Ya-Hui Chen Lance Horng Yu-Tai Shih 《Solid State Communications》2012,152(6):488-492
Zn0.8Co0.2O and Zn0.8Mn0.2O films were deposited on substrates by a sol–gel technique. X-ray diffraction, field-emission scanning electron microscopy, photoluminescence, and ferromagnetism measurements were used to characterize these dilute magnetic semiconductors. It is shown that the ferromagnetic properties might be related to the formation of acceptor-like defects in the Zn0.8Co0.2O and Zn0.8Mn0.2O films. It is found that ferromagnetic Zn0.8Mn0.2O has a higher Curie temperature than Zn0.8Co0.2O. In addition, the higher ratio of grain-boundary area to grain volume of Zn0.8Mn0.2O than Zn0.8Co0.2O indicates that grain boundaries and related acceptors are the intrinsic origin for ferromagnetism. 相似文献
15.
A different approach, aiming to achieve the constant blur status of point-spread function (PSF) at a certain defocused plane,
is described. The correlation between the two PSF is used to control the PSF blur similarity, and simultaneously the Strehl
ratio is also used to control the PSF blur minimization. By designing the PSF so that it is significantly insensitive to defocus
or related defocus quantity, for example, due to temperature change, all the constantly blurred images can be accurately de-blurred
by a simple inverse restoration filter for an adequate range of defocus. We refer to that as “software lens compensation”
and apply a design method to solve the athermalization of middle wavelength infrared (MWIR) imaging systems. The resultant
PSF is almost invariant in the temperature range from −10 to 50°C at the same focal plane. Consequently, the constant blur
spot can be removed by a simple digital signal processing. Thus, clear and sharp de-blurred images at different temperatures
are obtained. 相似文献
16.
Let be an algebraic number field. Let be a root of a polynomial which is solvable by radicals. Let be the splitting field of over . Let be a natural number divisible by the discriminant of the maximal abelian subextension of , as well as the exponent of , the Galois group of over . We show that an optimal nested radical with roots of unity for can be effectively constructed from the derived series of the solvable Galois group of over .
17.
John?F?StinsEmail author G?Caroline?M?van Baal Tinca?JC?Polderman Frank?C?Verhulst Dorret?I?Boomsma 《BMC neuroscience》2004,5(1):49
Background
There is great interest in appropriate phenotypes that serve as indicator of genetically transmitted frontal (dys)function, such as ADHD. Here we investigate the ability to deal with response conflict, and we ask to what extent performance variation on response interference tasks is caused by genetic variation. We tested a large sample of 12-year old monozygotic and dizygotic twins on two well-known and closely related response interference tasks; the color Stroop task and the Eriksen flanker task. Using structural equation modelling we assessed the heritability of several performance indices derived from those tasks. 相似文献18.
Huang YW Hu ST Yang SY Horng HE Hung JC Hong CY Yang HC Chao CH Lin CF 《Optics letters》2004,29(16):1867-1869
When an external magnetic field is applied parallel to the film surface of a magnetic fluid film, a high-quality one-dimensional periodic chain structure is formed when the field strength reaches a certain level. With a periodic chain structure in the magnetic fluid film, an incident light is diffracted onto the magnetic thin film. The results show that the one-dimensional periodic chain structure in the magnetic fluid film can serve as an optical grating. Further investigations reveal the feasibility of developing tunable coarse wavelength-division multiplexing by utilizing a periodic chain structure. 相似文献
19.
20.
Lap Mou Tam Juhn Horng Chen Hsien Keng Chen Wai Meng Si Tou 《Chaos, solitons, and fractals》2008,38(3):826-839
A system with more than one positive Lyapunov exponent can be classified as a hyperchaotic system. In this study, a sinusoidal perturbation was designed for generating hyperchaos from the Chen–Lee chaotic system. The hyperchaos was identified by the existence of two positive Lyapunov exponents and bifurcation diagrams. The system is hyperchaotic in several different regions of the parameters c, ε, and ω. It was found that this method not only can enhance or suppress chaotic behavior, but also induces chaos in non-chaotic parameter ranges. In addition, two interesting dynamical behaviors, Hopf bifurcation and intermittency, were also found in this study. 相似文献