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741.
Hui-Lu Wu Jing-Kun Yuan Ying Bai Fei Jia Bin Liu Fan Kou Jin Kong 《Transition Metal Chemistry》2011,36(8):819-827
Bis(N-allylbenzimidazol-2-ylmethyl)benzylamine (babb) and two of its complexes, [Cu(babb)(pic)2]·H2O (1) and [Co(babb)2](pic)2 (2) (pic = picrate), have been synthesized and characterized by physico-chemical and spectroscopic methods. Single crystal X-ray
diffraction revealed that the two complexes have similar distorted octahedral structures, but the degree of distortion and
the coordinated atoms are different. The DNA-binding properties of the free ligand and its two complexes have been investigated
by electronic absorption, fluorescence, and viscosity measurements. The results suggest that all three compounds bind to DNA
via an intercalative binding mode, and their binding affinity for DNA follows the order 2 > 1 > ligand. Additionally, both complexes exhibited potential antioxidant properties in in vitro studies, and complex 1 was the more effective. 相似文献
742.
Tetranuclear [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](ClO(4))(2)·2py (1), [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](NO(3))(2)·4py (2), and two-dimensional (2D) [Ni(4)(Hpzaox)(2)(pzaox)(2)(H(2)O)(2)](NO(3))(2)·2H(2)O (3) are prepared via the reaction of NiX(2)·6H(2)O and pyrazine-2-amidoxime (H(2)pzaox). All compounds contain [Ni(4)(Hpzaox)(2)(pzaox)(2)](2+) fragments, which assemble to form a tetranuclear or polymeric network. Magnetic studies show that the tetranuclear compounds display usual ferromagnetic coupling via the oxime N-O bridges, and the 2D compound displays unusual antiferromagnetic behavior. 相似文献
743.
Tests of consistency for the pair-wise comparison matrices have been studied extensively since AHP was introduced by Saaty in 1970s. However, existing methods are either too complicated to be applied in the revising process of the inconsistent comparison matrix or are difficult to preserve most of the original comparison information due to the use of a new pair-wise comparison matrix. Those methods might work for AHP but not for ANP as the comparison matrix of ANP needs to be strictly consistent. To improve the consistency ratio, this paper proposes a simple method, which combines the theorem of matrix multiplication, vectors dot product, and the definition of consistent pair-wise comparison matrix, to identify the inconsistent elements. The correctness of the proposed method is proved mathematically. The experimental studies have also shown that the proposed method is accurate and efficient in decision maker’s revising process to satisfy the consistency requirements of AHP/ANP. 相似文献
744.
In this paper, we study the semilocal convergence for a sixth-order variant of the Jarratt method for solving nonlinear equations
in Banach spaces. The semilocal convergence of this method is established by using recurrence relations. We derive the recurrence
relations for the method, and then prove an existence-uniqueness theorem, along with a priori error bounds which demonstrates
the R-order of the method. Finally, we give some numerical applications to demonstrate our approach. 相似文献
745.
In this paper, we study a variant of the super-Halley method with fourth-order convergence for nonlinear equations in Banach
spaces. We make an attempt to establish the semilocal convergence of this method by using recurrence relations. The recurrence
relations for the method are derived and then an existence-uniqueness theorem is given to establish the R-order of the method to be four and a priori error bounds. Finally, some numerical applications are presented to demonstrate
our approach. 相似文献
746.
Jian‐mei Li Rong‐rong Zang Min Li Dong Kou Juan Du 《Journal of Dispersion Science and Technology》2013,34(5):681-687
The kinetics of hydrolysis of p‐nitrophenyl picolinate(PNPP) catalyzed by metallomicelles formed from Cu (II), Ni (II) Schiff base complexes (CuL, NiL) and CTAB micelle were investigated in the pH range of 6.0–9.0 at 30°C. For the Cu (II) Schiff base complex CuL, the apparent rate constants (k obsd) of PNPP hydrolysis initially increased with the increasing pH of reaction media, then fell off. For the Ni (II) Schiff base complex NiL, the k obsd always increased with the increasing pH. The kinetic and thermodynamic parameters were calculated. The hydrolysis rate of PNPP catalyzed by Cu (II) complex was much larger than that by Ni (II) complex in CTAB micellar solution. The catalytic mechanism of the PNPP hydrolysis was discussed in detail, and the possibly active specie for the catalytic hydrolysis of PNPP was the monohydroxo metal complex. 相似文献
747.
Li-Juan Kou Rong-Ning Liang Xue-Wei Wang Yan Chen Wei Qin 《Analytical and bioanalytical chemistry》2013,405(14):4931-4936
The aim of this paper is to develop a potentiometric sensing methodology for sensitive and selective determination of neutral phenols by using a molecularly imprinted polymer as a receptor. Bisphenol A (BPA), a significant environmental contaminant, is employed as the model target. The BPA-imprinted polymer is synthesized by the semi-covalent technique and incorporated into a plasticized poly(vinyl chloride) membrane doped with the tridodecylmethylammonium salt. The present electrode shows a linear anionic potential response over the concentration range from 0.1 to 1 μM with a detection limit of 0.02 μM, and exhibits an excellent selectivity over other phenols. The proposed approach has been successfully applied to the determination of BPA released from real plastic samples. It offers promising potential in development of potentiometric sensors for measuring neutral phenols at trace levels. 相似文献
748.
In this paper, we study a class of improved Chebyshev–Halley methods in Banach spaces and prove the semilocal convergence for these methods. Compared with the super-Halley method, these methods need one less inversion of an operator, and the R-order of these methods is also higher than the one of super-Halley method under the same conditions. Using recurrence relations, we analyze the semilocal convergence for these methods under two different convergence conditions. The convergence theorems are proved to show the existence and uniqueness of a solution. We also give some numerical results to show our approach. 相似文献
749.
Shuang Xia David Utriainen Jin Tang Zhifeng Kou Gang Zheng Xuesong Wang Wen Shen E. Mark Haacke Guangming Lu 《Magnetic resonance imaging》2014
Decreased oxygen saturation in asymmetrically prominent cortical veins (APCV) seen in ischemic stroke has been hypothesized to correlate with an increase of de-oxygenated hemoglobin. Our goal is to quantify magnetic susceptibility to define APCV by establishing a cutoff above which the deoxyhemoglobin levels are considered abnormal. A retrospective study was conducted on 26 patients with acute ischemic stroke in one cerebral hemisphere that exhibited APCV with 30 age- and sex-matched healthy controls. Quantitative susceptibility mapping (QSM) was used to calculate the magnetic susceptibility of the cortical veins. A paired t-test was used to compare the susceptibility of the cortical veins in the left and right hemispheres for healthy controls as well as in the contralateral hemisphere for stroke patients with APCV. The change in oxygen saturation in the APCV relative to the contralateral side was calculated after thresholding the susceptibility using the mean plus two standard deviations of the contralateral side for each individual. The thresholded susceptibility value of the APCVs in the stroke hemisphere was 254 ± 48 ppb which was significantly higher (p < 0.05) than that in the contralateral hemisphere (123 ± 12 ppb) and in healthy controls (125 ± 8 ppb). There was a decrease of oxygen saturation in the APCV ranging from 16% to 44% relative to the veins of the contralateral hemisphere. In conclusion, APCV seen in SWI correspond to reduced levels of oxygen saturation and these abnormal veins can be identified using a susceptibility threshold on the QSM data. 相似文献
750.
The reactions of [MIII(CN)6]3? (M = Cr or Co) with CuII complexes of a tridentate schiff base [Cu(aemp)Cl] or [Cu(aemp)Ac]2 (Haemp = 2-[(2-amino-ethylimino)-methyl]-phenol) give rise to 1D cyanide-bridged bimetallic coordination polymers [Cu4(aemp)4(H2O)2][Cr(CN)6]Cl (1) and [Cu3(aemp)3(H2O)][Co(CN)6]·2H2O·MeOH (2). In complex 1, the six cyanide ligands of the [Cr(CN)6]3? moiety are involved in bridging, while in complex 2 only five cyanide ligands act as bridges to give a neutral chain. Magnetic studies reveal that complex 1 exhibits intermetallic ferromagnetic coupling, with J = 8.2 cm?1. 相似文献