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81.
Xuan Hao Dr. Hongsen Zhang Dr. Qi Liu Dr. Jingyuan Liu Dr. Rongrong Chen Dr. Jing Yu Prof. Milin Zhang Peili Liu Prof. Jun Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):590-597
Enrichment of UVI is an urgent project for nuclear energy development. Herein, magnetic graphitic carbon nitride nanosheets were successfully prepared by in situ anchoring of pyrrhotite (Fe7S8) on the graphitic carbon nitride nanosheet (CNNS), which were used for capturing UVI. The structural characterizations of Fe7S8/CNNS-1 indicated that the CNNS could prevent the aggregation of Fe7S8 and the saturation magnetization was 4.69 emu g−1, which meant that it was easy to separate the adsorbent from the solution. Adsorption experiments were performed to investigate the sorption properties. The results disclosed that the sorption data conformed to the Langmuir isotherm model with the maximum adsorption capacity of 572.78 mg g−1 at 298 K. The results of X-ray photoelectron spectroscopy (XPS) demonstrated that the main adsorption mechanism are as follows: UVI is adsorbed on the surface of Fe7S8/CNNS-1 through surface complexation initially, then it was reduced to insoluble UIV. Thereby, this work provided an efficient and easy to handle sorbent material for extraction of UVI. 相似文献
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A facile and efficient method has been developed for synthesis of β-iodocarboxylates in the presences of Ph3P/I2. Starting from epoxides, a series of β-iodocarboxylate compounds can be directly obtained in toluene media with excellent yields. Moreover, the method was successfully applied for the late-stage modification of natural products, such as isosteviol and vincamine derivatives, achieving the corresponding β-iodocarboxylates in good yields. 相似文献
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Synthesis,properties and mechanism of photodegradation of core–shell structured upconversion luminescent NaYF4:Yb3+,Er3+@BiOCl
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Shiyu Zhou Qiyan Zhang Deqiang Zhao Wenjuan Zong Zihong Fan Yaofang Sun Xuan Xu 《应用有机金属化学》2018,32(4)
Microspherical bismuth oxychloride (BiOCl) can only utilize ultraviolet (UV) light to promote photocatalytic reactions. To overcome this limitation, a uniform and thin BiOCl nanosheet was synthesized with a particle size of about 200 nm. As results of UV–visible diffuse reflectance spectroscopy showed, the band gap of this nanostructure was reduced to 2.78 eV, indicating that the BiOCl nanosheet could absorb and utilize visible light. Furthermore, the upconversion material NaYF4 doped with rare earth ions Yb3+ and Er3+ emitted visible light at 410 nm following excitation with near‐infrared (NIR) light (980 nm), which could be utilized by BiOCl to produce a photocatalytic reaction. To produce a high‐efficiency photocatalyst (NaYF4:Yb3+,Er3+@BiOCl), BiOCl‐loaded NaYF4:Yb3+,Er3+ was successfully synthesized via a simple two‐step hydrothermal method. The as‐synthesized material was confirmed using X‐ray diffraction, scanning electron microscopy, X‐ray photoelectron spectroscopy as well as other characterizations. The removal ratio of methylene blue by NaYF4:Yb3+,Er3+@BiOCl was much higher than that of BiOCl alone. Recycling experiments verified the stability of NaYF4:Yb3+,Er3+@BiOCl, which demonstrated excellent adsorption, strong visible‐light absorption and high electron–hole separation efficiency. Such properties are expected to be useful in practical applications, and a further understanding of the NIR‐light‐responsive photocatalytic mechanism of this new catalytic material would be conducive to improving its structural design and function. 相似文献
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Xuan Hien Nguyen 《Journal of Geometric Analysis》2013,23(3):1379-1426
We describe a construction of complete embedded self-translating surfaces under mean curvature flow by desingularizing the intersection of a finite family of grim reapers in general position. 相似文献
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This article presents an original work aimed at rationally designing molecularly imprinted polymer (MIP) toward a high specific adsorbent. Assembling with cobalt as the pivot, the MIP was prepared by coordinating polymerizable monomers around an inducible template. The use of pivot obviously plays a positive role on increasing the specificity of MIP, so as to adsorb more for the template and less for its analogue. Related studies indicate that these may be a result of increasing specific interaction, which makes the MIP capable of recognizing the imprint species. Further information from thermodynamic analysis reveals that the increasing specific interaction, in logic, can be due to a higher fidelity of imprint, which specifically allures the template to bind. 相似文献