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Baoding, China

Zhang K.,Central Institute for Correctional Police | Zhang D.,Institute of Penology
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

In this paper, we report six phosphorescent Cu(I) complexes with 1,10-phenanthroline-derived ligands and phosphorous ligands, including their synthesis, crystal structures, photophysical properties, and electronic nature. The Cu(I) center has a distorted tetrahedral geometry within the Cu(I) complexes. Theoretical calculation reveals that all emissions originate from triplet metal-to-ligand-charge-transfer excited state. It is found that the introduction of alkyl moieties into 2,9-positions of 1,10-phenanthroline is highly effective on restricting the geometric relaxation that occurs in excited states, which greatly enhances the photoluminescence (PL) performances, including PL quantum yield improvement, PL decay lifetime increase, and emission blue shift. © 2014 Elsevier B.V. All rights reserved. Source

Li X.,Hebei University | Zhang D.,Institute of Penology | Li J.,Agricultural University of Hebei
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

In this paper, a series of Eu(III) complexes based on four diamine ligands and two diketone ligands were synthesized. Their single crystal structures were studied, where intermolecular π-π stacking was found. The photophysical parameters of these Eu(III) complexes were measured, along with their ligand triplet levels. The energy transfer mechanism between ligand and metal center was discussed in detail. Energy transfer roll-back was found in Eu(III) complexes owing large-conjugated diamine ligands, compromising emissive performance. This energy transfer roll-back, however, could be stopped by the presence of AcO anion, leading to Eu(III) complex emission enhancement. The sensing performance of such Eu(III) complexes was thus investigated in detail. High sensitivity and selectivity were observed. © 2014 Elsevier B.V. All rights reserved. Source

Yu A.,Chinese Peoples Public Security University | Yu A.,Shenyang University of Technology | Zhang D.,Institute of Penology | Hu Y.,China Institute of Technology | Yang R.,Chinese Peoples Public Security University
Journal of Materials Science: Materials in Electronics

Sr3Al2O6:Eu2+, Dy3+ phosphors were synthesized by the polymer precursor method. The X-ray powder diffraction patterns show that the samples have a cubic structure with a space group of Pa3. In the excitation spectrum, the phosphors show a wide absorption in the UV region from 250 to 450 nm, which corresponds to the crystal field splitting of the Eu2+ d-orbital. All the emission spectrum of Sr3Al2O6:Eu2+, Dy3+ phosphors show the broad band emission peaked at about 518 nm, which can be ascribed to the typical 4f65d1 → 4f7 transitions of Eu2+ ions. And the best dopant concentration of Dy3+ ions for Sr3Al2O6:2 mol%Eu2+, xDy3+ phosphors is 2 mol%. The excitation wavelengths have no influences on emission peaks, but have clear influences on emission intensities. © 2014, Springer Science+Business Media New York. Source

Zhang K.,The Central Institute for Correctional Police | Zhang D.,Institute of Penology | Zhang K.,Institute of Law
WIT Transactions on Information and Communication Technologies

Aiming at characteristics of the treatment effect of compulsion detoxification, analytical hierarchy process (AHP) is adopted to construct treatment effect evaluation system model for quantitative evaluation. The weight of each evaluation factor is discussed according to path data obtained from regression analysis by MATLAB7.0. Then, on these grounds, in combination of experts' evaluation and value assigned, the treatment effect evaluation value of compulsion detoxification is finally worked out. The study shows such evaluation system is established on the basis of large sample survey and in combination of empirical research methods (such as questionnaire method and interview method) and computer technology, which overcomes the limitation of previous evaluation system with serious subjectivity. But, such diagnosis and evaluation system also needs further test and modification in practices. © 2014 WIT Press. Source

Zhang D.,Institute of Penology | Zhao S.,Institute of Penology | Zhang K.,Institute of Law | Ren X.,Institute of Penology | Hou Y.,Institute of Penology
Advanced Materials Research

A new method for preparing Acid pink 3B fluorescent magnetic powder was proposed based on theorthogonal theory and currentpreparing experience experiments of fingerprints development. The method contains two steps, first the level of each facor should be determined by the single factor expermint, then the best matrix of Acid pink 3B fluorescent magnetic powder should be selected by the orthogonal design theory. © (2012) Trans Tech Publications, Switzerland. Source

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