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51.
Zhu P Pan N Li R Dou J Zhang Y Cheng DY Wang D Ng DK Jiang J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(5):1425-1432
Reaction of heteroleptic bis(phthalocyaninato) lanthanide compounds [(Pc)M{Pc(OC8H17)8}] [H2Pc=unsubstituted phthalocyanine; H2Pc(OC8H17)8 = 2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyanine] with monomeric complexes [(Pc)M(acac)] (Hacac=acetylacetone), both of which generated in situ, led to the isolation of heteroleptic phthalocyaninato-[2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyaninato] lanthainde(III) triple-decker complexes [(Pc)M{Pc(OC8H17)8}] (M=Gd-Lu) (1-8) as the sole product. Heterodinuclear analogues [(Pc)Lu{Pc(OC8H17)8}M(Pc)] (M=Gd-Yb) (9-15) were obtained in a similar manner from the reaction of [(Pc)M{Pc(OC8H17)8}] (M=Gd-Yb) and [(Pc)Lu(acac)]. The molecular structures of the herterodinuclear compound [(Pc)Lu{Pc(OC8H17)8}Er(Pc)] (13) and its homodinuclear counterparts [(Pc)M{Pc(OC8H17)8}M(Pc)] (M=Er, Lu) (5, 8) have been determined by X-ray diffraction analysis; these structures exhibit a symmetrical molecular structure with one inner planar Pc(OC8H17)8 ligand and two outer domed Pc ligands. In addition to various spectroscopic analyses, the electrochemistry of these compounds has also been studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods, revealing the gradually enhanced pi-pi interactions among the phthalocyanine rings in the triple-deckers along with the lanthanide contraction. 相似文献
52.
Peihua Yang Dr. Kang Liu Qian Chen Dr. Xiaobao Mo Yishu Zhou Prof. Song Li Prof. Guang Feng Prof. Jun Zhou 《Angewandte Chemie (International ed. in English)》2016,55(39):12050-12053
Converting body heat into electricity is a promising strategy for supplying power to wearable electronics. To avoid the limitations of traditional solid‐state thermoelectric materials, such as frangibility and complex fabrication processes, we fabricated two types of thermogalvanic gel electrolytes with positive and negative thermo‐electrochemical Seebeck coefficients, respectively, which correspond to the n‐type and p‐type elements of a conventional thermoelectric generator. Such gel electrolytes exhibit not only moderate thermoelectric performance but also good mechanical properties. Based on these electrolytes, a flexible and wearable thermocell was designed with an output voltage approaching 1 V by utilizing body heat. This work may offer a new train of thought for the development of self‐powered wearable systems by harvesting low‐grade body heat. 相似文献
53.
Abstract We consider the problem of locating jumps in regression surfaces. A jump detection algorithm is suggested based on local least squares estimation. This method requires O(Nk) computations, where N is the sample size and k is the window width of the neighborhood. This property makes it possible to handle large data sets. The conditions imposed on the jump location curves, the jump surfaces, and the noise are mild. We demonstrate this method in detail with some numerical examples. 相似文献
54.
Congcong Zhang Lu Jing Sha Lin Zijuan Hao Jing Tian Prof. Xiaomei Zhang Prof. Peihua Zhu 《Chemphyschem》2013,14(16):3827-3833
Two optically active phthalocyanine derivatives with eight peripheral chiral (S)-4′-(2-methylbutoxy)biphenyl moieties on the β-position of the phthalocyanine ring are synthesized. The circular dichroism (CD) spectra show signals in the Q absorption region for both compounds 1 and 2 in chloroform solution, indicating the effective chiral-information transfer from the peripheral chiral (S)-4′-(2-methylbutoxy)biphenyl side chains to the phthalocyanine chromophore at the molecular level. Their self-assembling properties are further investigated by using electronic absorption and Fourier transform infrared spectroscopy, transmission electronic microscopy, scanning electronic microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Experimental results reveal the effect of the metal-coordination bond on molecular packing models in these nanostructures, which in turn results in the self-assembled nanostructures with different morphologies, from nanosheets for 1 to helical nanofibers for 2 . In addition, good semiconducting properties of the nanostructures fabricated from phthalocyanine derivatives 1 and 2 are revealed by current–voltage measurements. 相似文献
55.
Irène Gijbels Alexandre Lambert Peihua Qiu 《Annals of the Institute of Statistical Mathematics》2007,59(2):235-272
This paper deals with nonparametric estimation of a regression curve, where the estimation method should preserve possible
jumps in the curve. At each point x at which one wants to estimate the regression function, the method chooses in an adaptive way among three estimates: a local
linear estimate using only datapoints to the left of x, a local linear estimate based on only datapoints to the right of x, and finally a local linear estimate using data in a two-sided neighbourhood around x. The choice among these three estimates is made by looking at differences of the weighted residual mean squares of the three
fits. The resulting estimate preserves the jumps well and in addition gives smooth estimates of the continuity parts of the
curve. This property of compromise between local smoothing and jump-preserving is what distinguishes our method from most
previously proposed methods, that mainly focused on local smoothing and consequently blurred possible jumps, or mainly focused
on jump-preserving and hence led to rather noisy estimates in continuity regions of the underlying regression curve. Strong
consistency of the estimator is established and its performance is tested via a simulation study. This study also compares
the current method with some existing methods. The current method is illustrated in analyzing a real dataset. 相似文献
56.
我国船用惯导系统经过多年来的发展,其可靠性(MTBF)水平已达到××××小时以上。在国内现有的条件下,如何对此类机电一体化的高可靠、小子样产品的可靠性指标进行有效、经济、实用的验收呢?本文在综合分析现有的几种试验方法的基础上,结合多年的可靠性验收工作的实践,阐述了一套适合国情,行之有效的可靠性交收试验方法 相似文献
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60.
The influence of temperature on crosshatching on ablating cone models made of wax and camphor is studied. Ablation experiments
are carried out in supersonic tunnels. The relation between temperature and the wavelength of crosshatching is obtained. The
effect of pressure on the wavelength of crosshatching is verified. The influence of temperature and pressure on the initial
position of the appearance of crosshatching and on the time required for both the apperance of croosshatching and the formation
of stable crosshatching are obtained and analyzed. 相似文献