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101.
Dinghong Gu Li Huang Chunlei Shao Haojie Fang Renxi Zhang Huiqi Hou 《Frontiers of Chemistry in China》2007,2(4):436-441
The photodegradation of organic dye rhodamine B (RhB) in an aqueous solution was studied using a microwave electrodeless UV
lamp (MWUVL). The 185 nm vacuum UV (VUV) intensity of the MWUVL amounted to 12% of the total UV output, about 1.7 times as
high as that of the con ventional low-pressure mercury lamp. An acidic condition was preferred for the degradation of RhB.
Precipitate was generated during RhB degradation when the initial concentration of RhB solution was above 60 mg · L−1. For 100 mg · L−1 RhB at pH 4.0, the mass of precipitate produced was nearly half of the initial amount of RhB in the solution after irradi
ation for 75 min. The corresponding degradation ratio of RhB reached up to 99.4% and COD reduced 77.4%. The photo degradation
of RhB is mainly achieved by direct photolysis of RhB by 185 nm and OH radical oxidation.
__________
Translated from Journal of Fudan University (Natural Science), 2006, 45(6): 726–731 [译自: 复旦学报 (自然科学版)] 相似文献
102.
Dr. Yizhong Shen Chunlei Zhu Yunlong Wei Huanhuan Chen Zeyu Wu Prof. Yingwang Ye Prof. De-Man Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(22):e202200263
Precisely onsite monitoring of hypochlorite (ClO−) is of great significance to guide its rational use, reducing/avoiding its potential threat toward food safety and human health. Considering ClO− could quench fluorescence of curcumin (CCM) by oxidizing the o-methoxyphenol of CCM into benzoquinone, a portable ratiometric fluorescence sensor integrated with smartphone was designed for realizing the visual point-of-care testing (POCT) of ClO−. The amphiphilic phospholipid polymer was used as carrier to wrap curcumin, forming a novel liposome-encapsulated CCM, which provided a scaffold to bind with [Ru(bpy)3]2+ through electrostatic interaction, thus assembling [Ru(bpy)3]2+-functionalized liposome-encapsulated CCM ([Ru(bpy)3]2+@CCM-NPs). Further integrated with smartphone, visual imaging of [Ru(bpy)3]2+@CCM-NPs could be achieved and the accurate onsite detection of ClO− could be realized with a detection limit of 66.31 nM and a linear range of 0.2210 to 80.0 μM. In addition, the sensor could monitor ClO− in real samples with an onsite detection time of ∼154.0 s. 相似文献
103.
Jian Liu Chunlei Wu Huimin Jin Kui Du Hui Zheng 《Journal of heterocyclic chemistry》2019,56(11):3088-3092
A series of novel glycosyl nitrogen‐containing heterocycles derivatives were designed and synthesized. With the help of microwave, the reaction was carried out in water rapidly and afforded the target compounds in good yields. The acid catalysts that were essential for this kind of reaction under traditional heating method were avoided through this strategy. Preliminary biological evaluation showed that most of the compounds could inhibit the growth of A549 cells, but the inhibition of HepG‐2 cells was relatively poor. Notably, compound 2i displayed the best potency with an IC50 value of 3.42 μM against A549 cell lines, which is comparable with the common anticarcinogen paclitaxel (5.12 μM). Molecular modeling studies suggested that 2i may bind to the ATP‐binding site of epidermal growth factor receptor (EGFR), indicating a rational design strategy. These results provide a starting point for designing glycosyl nitrogen‐containing heterocycles as the potential drugs in lung cancer therapy. 相似文献
104.
105.
This article concerns the self-similar solutions to the hyperbolic mean curvature flow (HMCF) for plane curves, which is proposed by Kong, Liu, and Wang and relates to an earlier proposal for general flows by LeFloch and Smoczyk. We prove that all curves immersed in the plane which move in a self-similar manner under the HMCF are straight lines and circles. Moreover, it is found that a circle can either expand to a larger one and then converge to a point, or shrink directly and converge to a point, where the curvature approaches to infinity. 相似文献
106.
Chunlei Liu 《数学学报(英文版)》2000,16(3):535-540
Abstract
Hua’s estimate is established for character sums in a number field. A relationship between liftings of a character sum in
a local field is also studied.
This work is supported by NNSFC 相似文献
107.
Using elastic crystalline viscoplastic finite element (FE) annlysis, the formability of BCC steel sheets was assessed. An
orientation probability assignment method in the FE modeling procedure, which can be categorized as an inhomogenized material
modeling, was newly proposed. In the study, the crystal orientations of three materials, mild steel, dual phase steel and
the high strength steel, were obtained by X-ray diffraction and orientation distribution function (ODF) analyses. The measured
ODF results have revealed clearly different textures in the sheets, featured by orientation fibers, skeleton lines and selected
orientations in Euler angle space, which are closely related to the plastic anisotropy. Then, the crystal orientations were
assigned to FE integration points by using this ODF data, individually. The FE analyses of the standard limiting dome height(LDH)
test show how the fiber textures affect the extent of strain localization in the forming processes. It was confirmed by comparison
with experimental results that this FE code could predict the extreme strain localization and assess the sheet formability.
The third author is indebted to the National Natural Science Foundation of China for financial support (Grant No. 59875025)
to the research cooperation with OIT, Japan. 相似文献
108.
Shuhong Xu Chunlei Wang Yiping Cui 《International journal of quantum chemistry》2010,110(6):1287-1294
At DFT/B3LYP/6‐31G** theoretical level, C6H and C (n = 0, ?2, and +2), C6H and C (n = 0, ±2, ±4, and ±6), C6H (n = 0–6), as well as C6H6‐A and C6‐A (A = Be, B, N, O, Mg, Al, Si, S, and Fe) structures were investigated. Comparing NICS values of C6H and C (n = 0, ?2, and +2), we discovered that C6H, C6H were antiaromatic, and C6H6, C6, C, C had aromaticity with negative NICS values. According to research of C6H and C (n = 0, ±2, ±4, ±6), C6H (n = 0–6), we sustained that their σ and π orbit were different and the locations of electrons were difficult to confirm in ionic structures. Thus, neither 4n + 2 rule nor NICS values can precisely estimate the aromaticity of ionic structures. Besides, through WBI (NBO) research of C6H6‐A and C6‐A (A = Be, B, N, O, Mg, Al, Si, S, and Fe) structures, we found that C6H6 was easy to accept electrons, contrarily, C6 was prone to bestowing electrons. Moreover, C6H6 took the symmetrical carbon atoms form feeble interaction or bond, and C6 used all carbon atoms to impact with other atom. C6H6 generated two contrapuntal single bonds with oxygen, sulfur, and nitrogen atoms, whereas C6 molecule formed double bond with oxygen and nitrogen atoms, two conjoint single bonds with sulfur atom. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
109.
Lijuan Liu Chunlei Liu Xiaoyang Wang Z.G. Hu R.K. Li C.T. Chen 《Solid State Sciences》2009,11(4):841-844
K2Al2B2O7 (KABO) is a new nonlinear optical crystal capable of laser harmonic generation in the UV range. However, abnormal UV absorption prevents its application in effectively generating UV light with wavelength shorter than 300 nm. The transmittance spectra of the grown crystals show distinct absorption bands at 216 nm and 264 nm. It is observed that the UV absorption is strongly correlated with iron impurity at a parts per million (ppm) level. Furthermore, electron paramagnetic resonance (EPR) spectra of the absorbing crystals show a strong signal at g = 2.00 position corresponding to a Fe3+ center. A new crystal growth method which reduces the iron content has been proposed and results show that the new KABO crystal is free from the Fe3+ UV absorptions. 相似文献
110.
In this Letter, we report, for the first time in the multiphoton ionization regime, a comparison study of single-electron ionization of diatomic molecules versus rare gas atoms with virtually the same ionization potentials. In comparing N2+ to Ar+, a higher ion signal is seen in N2+ compared to Ar+ for linear polarization but the difference vanishes in circularly polarized light. In comparing O2+ to Xe+, we observe a suppression in O2+ compared to Xe+ for both linear and circular polarization but this suppression exhibits an intensity dependence; i.e., there is little suppression for O2+ at the lowest intensity range, but the suppression becomes increasingly stronger as the laser intensity increases. The multielectron screening model is used to discuss possible mechanisms of this intensity dependent suppression in O2+ in the multiphoton ionization regime. 相似文献