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1.
Dr. Chih‐Min Wang Li‐Wei Lee Tsung‐Yuan Chang Yen‐Chieh Chen Prof. Hsiu‐Mei Lin Prof. Kuang‐Lieh Lu Prof. Kwang‐Hwa Lii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1878-1881
An organic–inorganic hybrid zinc phosphate with 28‐ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5‐tri(4‐pyridyl)‐imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two‐dimensional organic–inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis. 相似文献
2.
Der‐Lii M. Tzou Lin‐Kai Ni Mei‐Man Chen Min‐Chuan Chiou Li‐Chou Chen Shan‐Te Hsu Kuo‐Lung Ku Chien‐Chung Cheng 《中国化学会会志》2013,60(9):1107-1112
Solid‐state Nuclear Magnetic Resonance (ss‐NMR) 13C single‐pulse excitation spectroscopy in combination with the magic‐angle spinning (MAS) technique was applied to a series of Phalaenopsis tissues, including the leaf, sheath, stem, and root, at different growth and spiking periods. Compared with{1H}/13C cross‐polarization MAS spectra, the 13C single‐pulse excitation MAS spectra displayed very distinct spectral patterns, recognizable as fingerprints of the tissues studied. 1Here, we demonstrate that solid‐state 13C single‐pulse excitation NMR spectroscopy provides a direct and robust analytical tool for studying the various tissues of Phalaenopsis in different growth and spiking induction periods. 相似文献
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Danni Wu Kathleen Joyce D. Carillo Shen‐Long Tsai Jiun‐Jie Shie Der‐Lii M. Tzou 《中国化学会会志》2019,66(10):1318-1326
The neurosteroid trans‐dehydroandrosterone (DHEA) and its analogs with slightly different modifications in the side chain attached to C17, that is, (3S)‐acetoxypregn‐5‐en‐20‐one ( 1 ) and (3S,20R)‐acetoxypregn‐5‐en‐20‐ol ( 2 ), have been synthesized to investigate DHEA–cation interactions. In this study, we applied solid‐state 1H/13C cross‐polarization/magic‐angle spinning (CP/MAS) nuclear magnetic resonance (NMR) spectroscopy to a series of DHEA analog/Mg2+ mixtures at different Mg2+ concentrations. The high‐resolution 13C NMR spectra of 1 /Mg2+ mixtures exhibit two distinct 13C spectral patterns, one attributable to 1 free from Mg2+, and the other attributable to 1 with bound Mg2+. For 2 , the 13C NMR spectra exhibit three distinct spectral patterns; besides that of the free form, the other two can be assigned to Mg2+‐bound forms. Based on the analysis of the chemical shift deviations (CSDs), we conclude that both 1 and 2 might be subject to a cation–π interaction via the C5–C6 double bond, in contrast to that observed previously for DHEA. As demonstrated, DHEA possesses two Mg2+ binding sites, that is, C17–O and C5–C6 double bond, in which the binding affinity of the former is at least three times stronger than that of the latter. The solid‐state 13C NMR investigation allows better understanding of the underlying cation binding effects of neurosteroid molecules in vitro. 相似文献
5.
Based on the propagation law of cross-spectral density function,
studied in this paper are the coherence vortices of partially
coherent, quasi-monochromatic singular beams with Gaussian
envelope and Schell-model correlator in the far field, where our
main attention is paid to the evolution of far-field coherence
vortices into intensity vortices of fully coherent beams. The
results show that, although there are usually no zeros of
intensity in partially coherent beams with Gaussian envelope and
Schell-model correlator, zeros of spectral degree of coherence
exist. The coherence vortices of spectral degree of coherence
depend on the relative coherence length, mode index and
positions of pairs of points. If a point and mode index are kept
fixed, the position of coherence vortices changes with the
increase of the relative coherence length. For the low coherent
case there is a circular phase dislocation. In the coherent
limit coherence vortices become intensity vortices of fully
coherent Laguerre--Gaussian beams. 相似文献
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This paper reports that the growth of RuOx(110) thin layer growth on Ru(0001)
has been investigated by means of scanning tunnelling microscope (STM). The STM
images showed a domain structure with three rotational domains of RuOx(110)
rotated by an angle of 120℃.
The as-grown RuOx(110) thin layer is expanded from the bulk-truncated
RuOx(110) due to the large mismatch between RuOx(110) and the
Ru(0001) substrate. The results also indicate that growth of RuOx(110)
thin layer on the Ru(0001) substrate by oxidation tends first to formation
of the Ru-O (oxygen) chains in the [001] direction of RuOx(110). 相似文献
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10.
The infrared and Raman laser spectra of RbVOPO4 were recorded and briefly discussed with the aid of factor group analysis. Some comparisons with the spectra of related materials were also made. 相似文献