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MEI Chong-Zhen WANG Hai-Rong XIONG Han-Lin MENG Rui-Jing SHAN Wen-Wen LI Hai-Hua 《结构化学》2014,(4):563-568
A new coordination polymer [Ni(L)(m-bix)(H2O)]n (1, H2L = 5-iodo-isophthalic acid, m-bix=1,3-bis(imidazol-1-ylmethyl)-benzene) has been synthesized by the hydrothermal method and characterized by IR, elemental analysis, powder XRD and single-crystal X-ray analysis. The crystal is of triclinic, space group Pī with a = 9.1638(3), b = 10.2319(3), c = 13.2463(4) ?, α = 80.1710(10), β = 83.671(2), γ = 70.3790(10)o,C22H19NiIN4O5, Mr = 605.02, V = 1150.85(6) ?3, Dc = 1.746 g/cm3, F(000) = 600, μ = 2.225 mm-1, S = 1.045 and Z = 2. The final R = 0.0388 and wR = 0.1257 for 5089 observed reflections with I 〉 2σ(I). In the title complex, the M and P layers are arranged alternately to give a double-layer structure by the symmetry related hydrogen bonds, and these double-layers are further joined together to achieve a 2D supramolecular architecture through I···π interaction involving iodine atoms and imidazole rings. The thermal stability of the title complex was studied by thermal gravimetric (TG) and differential thermal analysis (DTA). 相似文献
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Improved device reliability in organic light emitting devices by controlling the etching of indium zinc oxide anode
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A controllable etching process for indium zinc oxide (IZO) films was developed by using a weak etchant of oxalic acid with a slow etching ratio. With controllable etching time and temperature, a patterned IZO electrode with smoothed surface morphology and slope edge was achieved. For the practical application in organic light emitting devices (OLEDs), a sup- pression of the leak current in the current-voltage characteristics of OLEDs was observed. It resulted in a 1.6 times longer half lifetime in the IZO-based OLEDs compared to that using an indium tin oxide (ITO) anode etched by a conventional strong etchant of aqua regia. 相似文献
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《Discrete Mathematics》2023,346(1):113206
Two closed-form solutions of a general second order linear recurrence with variable coefficients are established. The first form is combinatorial in nature and is derived through the use of a set which counts the number of elements which are two units apart. The second form is closely related to continued fractions and is derived through the use of continued fraction-like relation. Several applications including a number of verifications of conjectures produced from the Ramanujan Machine are worked out, which illustrate its versatility in this respect. 相似文献
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Palle E.T. Jorgensen Erin P.J. Pearse 《Journal of Mathematical Analysis and Applications》2019,469(2):765-807
Motivated by applications to machine learning, we construct a reversible and irreducible Markov chain whose state space is a certain collection of measurable sets of a chosen l.c.h. space . We study the resulting network (connected undirected graph), including transience, Royden and Riesz decompositions, and kernel factorization. We describe a construction for Hilbert spaces of signed measures which comes equipped with a new notion of reproducing kernels and there is a unique solution to a regularized optimization problem involving the approximation of functions by functions of finite energy. The latter has applications to machine learning (for Markov random fields, for example). 相似文献
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Xing Li Zhi-Qin Sun Hong-Hong Chang Wen-Long Wei 《中国化学快报》2014,25(8):1174-1178
FeX3(X = Cl, Br) were found to be very effective reagents and powerful catalysts for regioselective ring openings of a variety of N-tosylaziridines with them to afford the corresponding b-haloamines in good to excellent yields with high regioselectivity under mild conditions. At the same time, 13 new compounds were obtained firstly. Moreover, the b-bromoamine prepared could be transferred into b-nitroamine with NaNO2 in moderate yield. 相似文献