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991.
992.
993.
Liu C Pan J Li S Zhao Y Wu LY Berkman CE Whorton AR Xian M 《Angewandte Chemie (International ed. in English)》2011,50(44):10327-10329
994.
DNA block copolymer doing it all: from selection to self-assembly of semiconducting carbon nanotubes
995.
996.
Samat Abdurehman Dr. Lang Liu Prof. Dianzeng Jia Jianping Hu Dr. Jixi Guo Prof. Xiaolin Xie 《Chemphyschem》2011,12(12):2338-2344
Two novel photochromic compounds, 1,3‐diphenyl‐4‐benzal‐5‐hydroxypyrazole 4‐phenylsemicarbazone ( 1 a ) and 1,3‐diphenyl‐4‐(4‐nitrobenzal)‐5‐hydroxypyrazole 4‐phenylsemicarbazone ( 2 a ), are synthesized and characterized by elemental analysis, mass spectrometry, FTIR spectroscopy, and 1H NMR spectroscopy. Their properties, including photochromic behavior, fluorescence properties, and thermal bleaching kinetics, are investigated. The results show that the two compounds exhibit improved photochromic performance in coloration and thermal bleaching rates, excellent photostability, high fatigue resistance, and reversible fluorescence switching properties in the solid state in comparison to reported pyrazolone thiosemicarbazones. The thermal bleaching process obeys first‐order kinetics. Bleaching of powders at 130 °C is completed within 90 s for 1 b (the colored isomer of 1 a ) and 150 s for 2 b (the colored isomer of 2 a ). The activation energy for the thermal bleaching process is determined to be 69 and 95 kJ mol?1, with frequency factors of 9.5×107 and 9.4×1010 s?1 for 1 b and 2 b , respectively. 相似文献
997.
Wu J Ma J Zhang Y Li Y Wang L Zhao Y Chen G Xiao L Jia S 《Physical chemistry chemical physics : PCCP》2011,13(42):18921-18925
We present a controllable three-dimensional fluorescence modulation technique for the high sensitive trap loss detection of ultracold molecules. The lowest vibrational levels (v = 0 and 1) of the pure long-range state 0(-)(g) (6S(1/2) + 6P(3/2)) of a cesium molecule are detected directly with high rotational resolution. Our technique proved to be a robust tool for effectively improving the detection sensitivity of trap loss spectroscopy. 相似文献
998.
Dr. Jia Wang Dr. Yong Chen Dr. Yuen‐Chi Law Meiyi Li Dr. Ming‐Xin Zhu Dr. Wei Lu Dr. Stephen Sin‐Yin Chui Dr. Nianyong Zhu Prof. Dr. Chi‐Ming Che 《化学:亚洲杂志》2011,6(11):3011-3019
A series of phosphorescent terpyridyl platinum(II) complexes with ancillary biphenylacetylide ligands, namely, [(R3tpy)PtC≡C(biphenyl)]X (R=tBu, H, or Et2N; tpy=2,2′;6′,2′′‐terpyridyl; X is an anion) were synthesized and structurally characterized by various spectroscopic techniques and X‐ray diffraction methods. Despite a lack of long alkyl chain(s) or hydrogen‐bonding motif(s), complexes [(tpy)PtC≡C(biphenyl)]Cl and [(tBu3tpy)PtC≡C(biphenyl)]X (X=Cl, ClO4, PF6, or BF4) were found to gelate water and organic solvents, respectively. The self‐aggregation of these complexes in solutions and the resulting gels were investigated with variable‐temperature (VT) 1H NMR spectroscopy, polarized optical microscopy, and absorption/emission spectroscopy. SEM micrographs on dry gels revealed entangled nanofibers with diameters of 20–40 nm and lengths of tens of micrometers. Powder X‐ray diffraction (PXRD) study revealed various degrees of crystallinity of these fibrillar nanostructures. The substituents on both the terpyridyl and acetylide ligands and counterion of these complexes play a profound but concerted role in tuning the intermolecular metal???metal and/or π–π interactions, and hence the gelation properties. 相似文献
999.
The structures of two new sesquiterpene lactones, 11,13beta-dihydroixerin Z (1) and Ixerin Z2 (2) isolated from Ixeris sonchifolia were determined to be 3-hydroxy-1(10),3-guaiadiene-12,6-olide-2-one-3-O-beta-D-glucopyranoside and 1(10),3,11 (13)-guaiatriene-12,6-olide-2-one-3-O-[6'-(4"-hydroxybenzyl lactyl)]-beta-D-glucopyranoside, respectively on the basis of detailed spectral analysis. 相似文献
1000.
Jia‐Jia Wei Na Zhang Yu‐Ling Wang Qing‐Yan Liu 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):m145-m148
The asymmetric unit of the title compound, [InNa(C3H5O3)4]n, consists of one InIII ion, one NaI ion and four crystallographically independent l ‐lactate monoanions. The coordination of the InIII ion is composed of five carboxylate O and two hydroxy O atoms in a distorted pentagonal–bipyramidal coordination geometry. The NaI ion is six‐coordinated by four carboxylate O atoms and two hydroxy O atoms from four l ‐lactate ligands in a distorted octahedral geometry. Each InIII ion is coordinated by four surrounding l ‐lactate ligands to form an [In(l ‐lactate)4]− unit, which is further linked by NaI ions through Na—O bonds to give a two‐dimensional layered structure. Hydrogen bonds between the hydroxy groups and carboxylate O atoms are observed between neighbouring layers. 相似文献