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101.
XU Hai-Bing XIE Zai-Lai ZHANG Li-Yi CHEN Zhong-Ning 《结构化学》2009,28(11):1470-1474
The title complex {Yb(hfac)3}2(bpyC≡CC6H4C≡Cbpy) (hfac = hexafluoroacetyl- acetonate,bpyC≡CC6H4C≡Cbpy=2-(pyridin-2-yl)-5-(2-(4-(2-(6-(pyridin-2-yl)pyridin-3-yl)ethynyl)- phenyl)ethynyl)pyridine) has been prepared and characterized by X-ray crystallography. It crystallizes in the monoclinic space group P21/c with a = 17.240(16), b = 25.64(2), c = 16.481(15)A, β = 93.469(9)°, V = 7271(12)A^3, Z = 4, Mr = 2022.91, F(000) = 3888, Dc = 1.848 g/cm^3 and μ(MoKα) = 2.708 mm^-1. The structure was refined to R = 0.0714 and wR = 0.1762 for 9771 observed reflections (I 〉 2σ(I)). Sensitized near-infrared (NIR) luminescence from YbIII centers was achieved through efficient antenna effect or energy transfer from the bridging ligand chromophore. 相似文献
102.
The performance of Partial Least Squares regression (PLS) in predicting the output with multivariate cross‐ and autocorrelated data is studied. With many correlated predictors of varying importance PLS does not always predict well and we propose a modified algorithm, Partitioned Partial Least Squares (PPLS). In PPLS the predictors are partitioned into smaller subgroups and the important subgroups with high prediction power are identified. Finally, regular PLS analysis using only those subgroups is performed. The proposed Partitioned PLS (PPLS) algorithm is used in the analysis of data from a real pharmaceutical batch fermentation process for which the process variables follow certain profiles during a specific fermentation period. We observed that PPLS leads to a more accurate prediction of the yield of the fermentation process and an easier interpretation, since fewer predictors are used in the final PLS prediction. In the application important issues such as alignment of the profiles from one batch to another and standardization of the predictors are also addressed. For instance, in PPLS noise magnification due to standardization does not seem to create problems as it might in regular PLS. Finally, PPLS is compared to several recently proposed functional PLS and PCR methods and a genetic algorithm for variable selection. More specifically for a couple of publicly available data sets with near infrared spectra it is shown that overall PPLS has lower cross‐validated error than PLS, PCR and the functional modifications hereof, and is similar in performance to a more complex genetic algorithm. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
103.
以Ln(NO3)3、H2pzdc(2,3-吡嗪-二羧酸)和prz(哌嗪)为原料,在水热条件下得到了2个结构新颖的稀土配位聚合物{(H2prz)[Ln2(pzdc)4(H2O)2]·5H2O}n(Ln=Eu(1),Tb(2))。对它们进行了元素分析、红外光谱、粉末X-射线衍射、热重等分析,并用X-射线衍射测定了它们的单晶结构。2个配合物的晶系都属于三斜晶系,P1空间群。研究了它们的荧光性质,固体荧光实验测试结果表明,2个配合物在室温下均表现出相应稀土离子的特征荧光发射。 相似文献
104.
Synthesis and Crystal Structure of a New Zn(Ⅱ) Complex Exhibiting Strong Luminescence 总被引:1,自引:1,他引:0
The title complex,[Zn(ip)2(H2O)2][ZnCl4]·H2O·2DMF 1(ip=imidazo[4,5-f][1,10] phenanthroline),has been synthesized via the slow evaporation of concentrated reaction solution at room temperature.It was characterized by single-crystal X-ray diffraction.Crystal data for C32H36Cl4N10O5Zn2:white prism,0.17mm×0.15mm×0.10mm,monoclinic,space group P2/c,a=11.928(8),b=9.868(6),c=16.520(11),β=104.879(12)°,V=1879(2)3,Z=2,Mr=913.25,Dc=1.614 g/cm3,F(000)=932,μ=1.616 mm-1,λ(MoKα)=0.71073,GOOF=1.045,R=0.0710 and wR=0.1755 for 3055 observed reflections with Ⅰ2σ(Ⅰ).X-ray diffraction study reveals that the title complex has an interesting 3D architecture via hydrogen bonding interactions and π-π interactions.The IR,TGA,XRD and luminescent properties of complex 1 were also studied. 相似文献
105.
The title compound, [Cu_4I_4(C_4H_8N_4)_4], has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group Pbca, with α =18.1851(10), b = 9.3697(5), c = 19.8034(10)(A), V= 3374.3(3) (A)~3, C_(16)H_(32)Cu_4I_4N_(16), M_r = 1210.34, Z= 4, Dc= 2.383 g/cm~3,μ = 6.183 mm~(-1), F(000) = 2272, S = 1.032, the final R = 0.0309 and wR =0.1180 for 3854 observer reflections (I> 2σ(I)). The structure of the title compound consists of tetranuclear copper cluster units bridged by the halogen atoms with the 3,5-dimethyl-4-aminotriazole ligands coordinated to the metal ions through the triazole nitrogen atoms. The luminescent property of 1 was also studied. 相似文献
106.
Synthesis,Crystal Structure and Luminescent Property of a New Copper(Ⅰ) Iodide Complex Based on 3,5-Dimethyl-4-amino-triazole 总被引:1,自引:1,他引:0
The title compound,[Cu4I4(C4H8N4)4],has been synthesized and characterized by single-crystal X-ray diffraction analysis.It crystallizes in monoclinic,space group Pbca,with a=18.1851(10),b=9.3697(5),c=19.8034(10),V=3374.3(3)3,C16H32Cu4I4N16,Mr=1210.34,Z=4,Dc=2.383 g/cm3,μ=6.183 mm-1,F(000)=2272,S=1.032,the final R=0.0309 and wR=0.1180 for 3854 observer reflections(I2σ(I)).The structure of the title compound consists of tetranuclear copper cluster units bridged by the halogen atoms with the 3,5-dimethyl-4-aminotriazole ligands coordinated to the metal ions through the triazole nitrogen atoms.The luminescent property of 1 was also studied. 相似文献
107.
The title compound,[Zn2(H2C4BIm)(ox)2]·2H2O(1,H2C4BIm = 2,2'-(1,4-bu-tanediyl)bis(1H-benzimidazole),has been synthesized by the hydrothermal reaction of Zn(NO3)2·6H2O with H2C4BIm and Na2C2O4 in water solution.It crystallizes in the triclinic system,space group P1 with a = 9.445(9),b = 9.598(9),c = 14.962(14) ,α = 72.160(10),β = 79.905(12),γ = 83.680(11)°,Mr = 633.18,V = 1269(2) 3,Z = 2,Dc = 1.657 g/cm3,F(000) = 644,μ = 1.953 mm-1,the final R = 0.0671 and wR = 0.1689.X-ray crystal structure analysis revealed that 1 is a 3D network with(203)2(20)3 topology in which the ZnII atom can be considered as a 3-connected node and both ox2-and H2C4BIm serve as the linear linkers. 相似文献
108.
Near-infrared (NIR) persistent luminescent β-Ga2O3:Cr3+ nanowire assemblies were synthesized by a hydrothermal process followed by calcination. The phosphor exhibits more than 4 h afterglow in the wavelength range of 650-850 nm after ceasing the ultraviolet light (280-360 nm) irradiation. The trap structure and persistent luminescence mechanism were revealed by thermoluminescence measurement. The β-Ga2O3:Cr3+ nanowire assemblies may find applications as identification taggants in security and optical probes in bio-imaging. 相似文献
109.
110.