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61.
Chun-Sheng Jia Tao Chen Liang-Zhong Yi Shu-Rong Lin 《Journal of mathematical chemistry》2013,51(8):2165-2172
By applying the dissociation energy and the equilibrium bond length for a diatomic molecule as explicit parameters, we generate an improved expression for the deformed Rosen–Morse potential energy model. It is found that the deformed Rosen–Morse potential model and the well-known Tietz potential model are the same empirical potential function for diatomic molecules. With the help of the energy spectrum expression of the deformed Rosen–Morse potential model, we obtain exact closed-form expressions of diatomic anharmonicity constants $\omega _e x_e $ ω e x e and $\omega _e y_e $ ω e y e . 相似文献
62.
A series of symmetrical and unsymmetrical phenylene-vinylene (PV) based chro- mophores with the molecular configuration of donor-π-donor (D-g-D) were prepared and characterized. Iodine was first introduced into the Jr-conjugation backbone of the PV based chromophores in order to study the heavy atom effect on their linear absorption, two-photon absorption (TPA) properties, as well as singlet oxygen generation properties. TPA cross-sections of these chromophores were investigated by using the two-photon excited fluorescence method. The unsymmetrical chromophores were found to have larger TPA cross-section values compared to their symmetrical counterparts. For one of the unsymmetrical chromophores with the iodine incorporation, a large TPA cross section value with quenched emission was found. The decreased fluorescence quantum yield of a molecule can be ascribed to the increased intersystem crossing, which is favorable for enhancing the singlet oxygen generation. Therefore, the unsymmetrical PV based chromophores with heavy atom incorporation are promising singlet oxygen sensitizers for the photodynamic therapy application. 相似文献
63.
Postsynaptic Potentials and Morphological Features of Tectal Cells in Homing Pigeons 总被引:1,自引:0,他引:1
In this study postsynaptic potentials responding to the electrical stimulation of the optic nerve and the nucleus isthmipars parvocellularis (Ipc) were intracellularly recorded from 86 tectal cells in pigeons, 13 of which were marked with Lucifer yellow (LY). According to types of postsynaptic potentials and their succesion, the postsynaptic responses could be classified into four types: excitatory postsynaptic potential (EPSP)-inhibitory postsynaptic potential (IPSP) sequence (EI type), E, I and IE types.Among them, E or EI responses were mainly produced to the optic nerve stimulation, while the electrical stimulation of the lpc elicited I responses in more than half the recorded cells.LY-marked tectal cells included five ganglionic cells, four pyramidal cells, two bipolar cells and two stellate cells.The ganglionic cells were mainly located in tectal layers Ⅲ and Ⅳ, whereas the others were in layer Ⅱ.It appears from both intracellular recordings and fluorescent markings that there is some correlati 相似文献
64.
Hong-Yan Wu Hong Li Bao-Lin Zhu Shu-Rong Wang Shou-Min Zhang Shi-Hua Wu Wei-Ping Huang 《Transition Metal Chemistry》2008,33(1):9-15
Two new blue luminescent Zn(II) complexes, [ZnL2(H2O)]Cl2 · H2O (1) and [ZnL2Cl][ZnLCl2] · NO3 (2) (L = 2-aminomethylbenzimidazole) have been synthesized and characterized spectroscopically and crystallographically. The
structure of complex (1) can be described as a square pyramid. In the complex (2), there are two units [ZnLCl2] (a), and [ZnL2Cl]+ (b), which have a distorted tetrahedral geometry and a slightly distorted trigonal bipyramidal coordination geometry, respectively.
In these complexes, significant multiple inter- and intra-molecular hydrogen bonding and π–π stacking interactions are shown.
These contacts lead to aggregation and supramolecular assembly of complexes (1) and (2) into 3D and 2D frameworks, respectively. Fluorescent analysis in the dilute DMF solution and solid state shows that both
complexes exhibit intense emission in blue region. They display high blue luminescence quantum efficiency due to a metal-to-ligand
charge transfer (MLCT) and have a bathochromic shift of the emission energy compared with the free ligand L. The emission
intensity of complex (2) is higher than that of complex (1). 相似文献
65.
Hai-Yan Feng Shu-Rong Hou Na Zheng Xiang-Jun Li Zhong-Bo Hu Zhuo-Bin Yuan 《Chromatographia》2008,68(5-6):431-435
A rapid capillary electrophoresis method based on online acid barrage stacking has been successfully established for analysis of trace amounts of genistein in human plasma. Genistein was analyzed within 8 min, with 200 mmol L?1 citric acid (pH 1.7) as acid barrage, and injection times of 180 and 30 s for sample and acid, respectively. Good linearity was obtained in the range 0.05–5 mg L?1 and the limit of detection was 0.03 mg L?1. Compared with normal sample injection, this method resulted in more than a fiftyfold improvement in detection sensitivity. The technique has potential for use in studies of genistein metabolism and of exposure levels in humans. 相似文献
66.
采用酸蒸气水热免洗方法合成了立方ZrW2O8类型化合物的系列前驱物ZrMo2-xWxO7(OH, Cl)2·2H2O(x=0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8), 并由此制备了纯立方相ZrMo2-xWxO8(x=0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8). 提出了用X射线粉末衍射相对积分强度表征有序-无序介稳态晶体有序度的方法, 发现在制备条件下, 随着Mo/W摩尔比的减小, 立方相ZrMo2-xWxO8有序-无序介稳态的饱和有序度增加的规律. 讨论了原料选择以及中间产物的形貌对合成目标产物的影响, 探讨了以铵盐为原料制备前驱物反应的微观过程. 相似文献
67.
Yan Shu-Rong Kalbasi Rasool Karimipour Aliakbar Afrand Masoud 《Journal of Thermal Analysis and Calorimetry》2021,145(5):2809-2816
Journal of Thermal Analysis and Calorimetry - In this study, the efficacy of adding nanoparticles of MWCNTs to the base fluid of paraffin on the thermal conductivity has been investigated.... 相似文献
68.
Yi-Yin Zheng Shan-Tong Chen Zhi-Peng Huang Shi-Xuan Dai Bin Liu Yong-Yao Li Shu-Rong Wang 《Frontiers of Physics》2021,16(2):22501
We study the stability of zero-vorticity and vortex lattice quantum droplets (LQDs), which are described by a two-dimensional (2D) Gross–Pitaevskii (GP) equation with a periodic potential and Lee– Huang–Yang (LHY) term. The LQDs are divided in two types: onsite-centered and offsite-centered LQDs, the centers of which are located at the minimum and the maximum of the potential, respectively. The stability areas of these two types of LQDs with different number of sites for zero-vorticity and vorticity with S = 1 are given. We found that the μ–N relationship of the stable LQDs with a fixed number of sites can violate the Vakhitov–Kolokolov (VK) criterion, which is a necessary stability condition for nonlinear modes with an attractive interaction. Moreover, the μ–N relationship shows that two types of vortex LQDs with the same number of sites are degenerated, while the zero-vorticity LQDs are not degenerated. It is worth mentioning that the offsite-centered LQDs with zero-vorticity and vortex LQDs with S = 1 are heterogeneous. 相似文献
69.
研究了一维光晶格中超流费米气体的能隙孤子. 应用平均场理论和超流费米气体的流体动力学模型, 利用变分法得到了在整个跨越区超流费米气体在光晶格中存在带隙孤子的条件, 即原子间的非线性相互作用项与系统化学势以及晶格深度的相互关系. 通过对超流费米气体的基态能隙孤子空间分布的分析与对比, 揭示了在一维情况下超流费米气体能隙孤子的存在并发现超流费米气体能隙孤子在整个跨越区当系统从Bose-Einstein凝聚端跨越到BCS端时孤子存在的条件与孤子空间分布存在明显的差别. 相似文献
70.
A rapid non-separative spectrofluorometric method based on the second-order calibration of excitation-emission matrix (EEM) fluorescence was proposed for the determination of napropamide (NAP) in soil, river sediment, and wastewater as well as river water samples. With 0.10 mol L−1 sodium citrate-hydrochloric acid (HCl) buffer solution of pH 2.2, the system of NAP has a large increase in fluorescence intensity. To handle the intrinsic fluorescence interferences of environmental samples, the alternating penalty trilinear decomposition (APTLD) algorithm as an efficient second-order calibration method was employed. Satisfactory results have been achieved for NAP in complex environmental samples. The limit of detection obtained for NAP in soil, river sediment, wastewater and river water samples were 0.80, 0.24, 0.12, 0.071 ng mL−1, respectively. Furthermore, in order to fully investigate the performance of second-order calibration method, we test the second-order calibration method using different calibration approaches including the single matrix model, the intra-day various matrices model and the global model based on the APTLD algorithm with nature environmental datasets. The results showed the second-order calibration methods also enable one or more analyte(s) of interest to be determined simultaneously in the samples with various types of matrices. The maintenance of second-order advantage has been demonstrated in simultaneous determinations of the analyte of interests in the environmental samples of various matrices. 相似文献