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61.
The Aerobic Oxidation and C=C Bond Cleavage of Styrenes Catalyzed by Cerium(IV) Ammonium Nitrate (CAN) 下载免费PDF全文
Lei Yu Yaping Huang Zengbing Bai Bingchun Zhu Kehong Ding Tian Chen Yuanhua Ding Yuguang Wang 《中国化学会会志》2015,62(6):479-482
The CAN‐catalyzed aerobic oxidation severed the C=C bond selectively through the single electron transfer mechanism, giving a green method to decompose olefins. Compared with the literature reported examples, this method required simple catalyst, cheap, abundant and clean oxidant and was very safe to operate due to the mild conditions. 相似文献
62.
Fabrication of the Monolithic Fiber for the Solid Phase Micro‐extraction of Malachite Green 下载免费PDF全文
A monolithic fiber of molecularly imprinted polymer (MIP) was prepared by in situ polymerization within the capillary with an inner diameter of 530 µm. It was carried out in 8 min by microwave irradiation using malachite green (MG) as a template molecule, α‐methacrylic acid (MAA) as a functional monomer, acetonitrile (ACN) as a porogenic solvent, ethylene dimethacrylate (EDMA) as a crosslinker, azodiiso‐butyronitrile (AIBN) as a thermal initiator. The resulted MIP fibers were pushed out from the capillary, eluted and inserted in the capillary again, which successfully used for the solid phase microextraction (SPME) procedure. The factors affecting the extraction of MG, such as the molar ratio of template/monomer (MG/MAA), concentration of NaCl, extraction and desorption time, and extraction and desorption solvents were investigated in detail. The selectivity of the MIP fibers was compared using MG analogues crystal violet (CV) and non‐analogue Sudan II. It was also employed for the pretreatment of trace MG in the fish feed followed by high‐performance liquid chromatography (HPLC) detection. Under the optimal conditions, the linear range of MG was 10‐600 μg/L, the detection limit (LOD) was 1.23 μg/L and the recovery of spiked fish feed sample was 88.7~113.9%. 相似文献
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Electrodeposition and characterization of Zn–Sn alloy coatings from a deep eutectic solvent based on choline chloride for corrosion protection 下载免费PDF全文
S. Fashu C. D. Gu J. L. Zhang W. Q. Bai X. L. Wang J. P. Tu 《Surface and interface analysis : SIA》2015,47(3):403-412
With the aim of obtaining high corrosion resistant Zn–Sn alloy coatings from an ionic liquid, the effects of electrodeposition potential and electrolyte composition on the electrodeposition behavior, film composition, morphology and corrosion performance were investigated. Cyclic voltammograms indicate that Zn and Sn were co‐deposited at distinct reduction potentials as pure Zn and Sn elements. In addition, the phase composition analysis also showed that the obtained Zn–Sn alloy deposits (8 wt.%–45 wt.% Zn) consist of a two‐phase mechanical mixture of small aggregates of Zn and Sn metals. The Zn content of the alloy significantly increases as the electrodeposition potential and electrolyte Zn (II)/Sn (II) ratio increase. The corrosion performance study of the obtained Zn–Sn coatings showed that they have a passivation behavior and their corrosion resistance increases as the alloy‐Sn content increases. To improve their morphological properties, ethylene diamine tetraacetic acid additive was introduced into the electrolyte and greatly improved the morphology and corrosion resistance of the deposits. For the first time, it was shown that high corrosion resistance Zn–Sn coatings can be obtained from ionic liquids. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
67.
A Designed TiO2/Carbon Nanocomposite as a High‐Efficiency Lithium‐Ion Battery Anode and Photocatalyst 下载免费PDF全文
Liang Peng Dr. Huijuan Zhang Yuanjuan Bai Yangyang Feng Prof. Yu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(42):14871-14878
Herein, a peapod‐like TiO2/carbon nanocomposite has successfully been synthesized by a rational method for the first time. The novel nanostructure exhibits a distinct feature of TiO2 nanoparticles encapsulated inside and the carbon fiber coating outside. In the synthetic process, H2Ti3O7 nanotubes serve as precursors and templates, and glucose molecules act as the green carbon source. With the alliciency of hydrogen bonding between H2Ti3O7 and glucose, a thin polymer layer is hydrothermally assembled and subsequently converted into carbon fibers through calcinations under an inert atmosphere. Meanwhile, the precursors of H2Ti3O7 nanotubes are transformed into the TiO2 nanoparticles encapsulated in carbon fibers. The achieved unique nanocomposites can be used as excellent anode materials in lithium‐ion batteries (LIBs) and photocatalytic reagents in the degradation of rhodamine B. Due to the synergistic effect derived from TiO2 nanoparticles and carbon fibers, the obtained peapod‐like TiO2/carbon cannot only deliver a high specific capacity of 160 mAh g?1 over 500 cycles in LIBs, but also perform a much faster photodegradation rate than bare TiO2 and P25. Furthermore, owing to the low cost, environmental friendliness as well as abundant source, this novel TiO2/carbon nanocomposite will have a great potential to be extended to other application fields, such as specific catalysis, gas sensing, and photovoltaics. 相似文献
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Frontispiece: A Step‐by‐Step Assembly of a 3D Coordination Polymer in the Solid‐State by Desolvation and [2+2] Cycloaddition Reactions 下载免费PDF全文
69.
Huiyu Bai Yufei Li Wei Wang Guangliang Chen Orlando J. Rojas Weifu Dong Xiaoya Liu 《Cellulose (London, England)》2015,22(6):3877-3894
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利用α-环糊精(α-CD)与含有聚乙二醇(PEG)链段的聚合物Pluronic F127的超分子作用制备水凝胶.该物理交联水凝胶的交联点包括α-CD与PEG链包合物堆积形成的微晶区和聚合物疏水链段聚集区.优化水凝胶组分,得到具有较低固含量和较短凝胶化时间的体系用于胰岛素的负载和释放研究.通过X射线衍射(XRD),扫描显微镜(SEM)对水凝胶结构进行表征.通过紫外分光光度计监测胰岛素的释放过程,结果表明,水凝胶释药时间约为65 h,且释放曲线较为平缓.细胞毒性实验结果表明该水凝胶材料对细胞生长无明显抑制作用.小鼠体内释药实验结果表明该水凝胶载体对延长胰岛素的释药时间有一定效果,可作为多肽类药物的缓释体系. 相似文献