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61.
Xia Peng Shaojun Wang Xiaomin Zhang You Shu Shengpei Su Jin Zhu 《Cellulose (London, England)》2017,24(11):4683-4689
In this work, cellulose–Ag@AgCl composite films have been fabricated directly through a one-step coagulation of a cellulose/1-butyl-3-methylimidazolium chloride (BmimCl) solution with AgNO3 and PVP. The AgCl was formed upon the addition of AgNO3 to a cellulose/BmimCl solution, and underwent further reaction with excess Cl?, leading to the complete dissolution of AgCl. The AgCl crystals were regenerated on the cellulose matrix during the coagulation process. The AgCl was partial decomposed to Ag0 and formed Ag@AgCl under visible light irradiation. The morphology of Ag@AgCl in the cellulose matrix was controlled by varying the concentration of PVP. The addition of PVP enabled the formation of stable cellulose films embedded with Ag@AgCl. The composite film demonstrated efficient photodegradation of methyl orange, which was retained upon recycling. This work thus provides a simple pathway for the preparation of Ag@AgCl embedded on a polymer support via one-step coagulation. 相似文献
62.
Xue-Min Tan Qiao-Mei Lai Zhi-Wei Yang Xiao Long Hai-Lin Zhou Xiao-Lin You Xiao-Jie Jiang Hai-Lei Cui 《Tetrahedron letters》2017,58(2):163-167
A La(OTf)3 catalyzed synthesis of tetrasubstituted pyrroles under microwave irradiation has been developed affording various α-aryl tetrasubstituted pyrroles in acceptable to good yields (36–82% yield) through condensation/alkyne azacyclization/isomerization sequence. Functionalized α-aryl pentasubstituted pyrroles could be prepared from tetrasubstituted pyrroles through easy transformations. 相似文献
63.
Hongbo Zhu Ziping Cao Xin Meng Laijin Tian Guang Chen Xuejun Sun Jinmao You 《Tetrahedron》2017,73(24):3310-3315
Acid-mediated domino reaction of ortho-carbonylated alkynyl-substituted arylaldehydes with phenols is described. The implement of this reaction can provide directly a variety of tetracyclic indeno[2,1-c]chromen-7-one products in good yields. The mechanism was proposed to be a domino indanone ring formation/ortho-alkylation of phenols/dehydrated cyclization for the formation of polycyclic skeleton. In addition, several interesting dimeric products containing a pentacyclic scaffold were also afforded stereoselectively albeit in moderate yields. The present transformations feature the use of simple acid catalyst, short reaction time and good substrate scope. 相似文献
64.
An efficient and thermally induced reaction of diazoamide with isatin under mild reaction conditions is described, which provides a complementary approach to the 3,3′-bioxindole in high yields with excellent diastereoselectivity. In comparison to the metal-catalyzed versions, this is the only example under catalyst-free conditions via a non-carbene reaction pathway. 相似文献
65.
Fangying?Lv Ning?GanEmail author Jie?Huang Futao?Hu Yuting?CaoEmail author You?Zhou Youren?Dong Li?Zhang Shan?Jiang 《Mikrochimica acta》2017,184(8):2561-2568
The authors describe an ultrasonic-assisted headspace method for solid phase micro-extraction (UA-HS-SPME) of 7 polychlorinated biphenyls (PCBs) with codes PCB28, PCB52, PCB101, PCB118, PCB138, PCB153 and PCB180. The coating is based on a poly-dopamine metal-organic framework [PDA-MIL-53(Fe)] on a stainless steel wire. The coating can be prepared and evenly deposited on the stainless fiber by dipping the PDA fiber into a solution of MIL-53(Fe). The assay is also environmentally friendly because water is used as the solvent. The effects of extraction time, addition of salts, pH value and power of ultrasonic power were optimized. The coating is found to possess a high selectivity and adsorption capacity for PCBs compared to commercial SPME fibers such as the divinylbenzene/carboxen/polydimethylsiloxane fibers. Following desorption, the PCBs were quantified by GC-MS. The detection limits are between 50 and 90 pg?g?1 of PCBs in soil. The fibers can be easily prepared, and the batch-to-batch reproducibility (RDS) is <10% (for n = 6). The fibers are inexpensive, re-usable and can be easily manipulated, and particularly well suited for screening polychlorinated biphenyls in soil. 相似文献
66.
Shu Xia Wang Yan Qin Yongqiang Yu Cuiping Zhang Jianfang Zhao Jiebo Cui Jiewu Cui Lihua Zheng Hongmei Zhang Yong Wang Wenfang Wu Yucheng 《Journal of Solid State Electrochemistry》2017,21(5):1489-1497
Journal of Solid State Electrochemistry - Binder-free, high-performance electrode materials play a critical role for supercapacitors. In this paper, through the electrochemical anodization process,... 相似文献
67.
68.
Terence Zhi Xiang Hong Liming You Madhavi Dahanayaka Adrian Wing-Keung Law Kun Zhou 《Molecules (Basel, Switzerland)》2021,26(11)
In this study, molecular dynamics simulation is used to investigate the effects of water-based substitutional defects in zeolitic imidazolate frameworks (ZIF)-8 membranes on their reverse osmosis (RO) desalination performance. ZIF-8 unit cells containing up to three defect sites are used to construct the membranes. These substitutional defects can either be Zn defects or linker defects. The RO desalination performance of the membranes is assessed in terms of the water flux and ion rejection rate. The effects of defects on the interactions between the ZIF-8 membranes and NaCl are investigated and explained with respect to the radial distribution function (RDF) and ion density distribution. The results show that ion adsorption on the membranes occurs at either the nitrogen atoms or the defect sites. Complete NaCl rejection can be achieved by introducing defects to change the size of the pores. It has also been discovered that the presence of linker defects increases membrane hydrophilicity. Overall, molecular dynamics simulations have been used in this study to show that water-based substitutional defects in a ZIF-8 structure reduce the water flux and influence its hydrophilicity and ion adsorption performance, which is useful in predicting the type and number of defect sites per unit cell required for RO applications. Of the seven ZIF-8 structures tested, pristine ZIF-8 exhibits the best RO desalination performance. 相似文献
69.
70.
脑疾病的诊疗、 探索高级脑功能机制和理解意识本源对脑科学研究具有重要意义. 成像技术在阐明脑科学神经系统结构和功能中发挥了重要作用. 迄今, 核磁共振成像、 光学成像和电子显微镜成像技术已为脑科学研究提供了强有力的手段, 取得了突出的进展. 同步辐射X射线显微成像技术具有高分辨率、 快成像速度和高穿透深度等优点, 是一类与已有技术互补的新型脑成像技术. 本文介绍了核磁共振波谱、 光学显微镜和电子显微镜等成像方法在脑成像领域中的应用, 重点阐述了同步辐射X射线成像的优势以及在脑结构成像和功能成像中的应用. 在此基础上, 展望了同步辐射X射线成像应用于脑科学研究的未来发展方向, 讨论了该技术在绘制人脑联接图谱中的优势及可行性. 相似文献