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951.
Miras HN Long DL Kögerler P Cronin L 《Dalton transactions (Cambridge, England : 2003)》2008,(2):214-221
A family of polyoxometalates with the composition [H2V3M17O62](6-) features a Dawson-like architecture containing two tetrahedral {VVO4} templates rather than main group hetero-anions ({PO4} or {SO4} etc.) typically associated with classical heteropolyacids, situated within a mixed-metal {MVI17VIVO54} cage and these clusters were first discovered using mass spectrometry. 相似文献
952.
953.
研究了N,N,N′,N′-四辛基-3-氧戊二酰胺(TODGA)溶于疏水性离子液体咪唑类离子液体1-乙基-3-甲基咪唑双三氟甲磺酰亚胺盐([C2mim][NTf2])中对硝酸水溶液体系中四价钍离子(Th4+)的萃取行为。详细考察了接触时间、酸度、Th4+浓度、TODGA浓度、温度对TODGA/[C2mim][NTf2]体系萃取性能的影响。作为对比,我们还考察了TODGA在传统有机溶剂异辛烷中对Th4+的萃取。结果表明:TODGA/[C2mim][NTf2]体系对Th4+的萃取是吸热反应,且在50℃下,能在5 min内达到平衡。萃取体系随着酸度对Th4+的萃取性能先降后增大;Th4+浓度的增大,TODGA浓度的降低,对Th4+的萃取性能下降。TODGA在离子液体萃取体系中比在有机体系中有更好的Th4+萃取效果,特别是在低酸条件下。通过萃取机理研究,推测出在低酸下萃取反应是离子交换且TODGA与Th4+配比为2∶1,在高酸下萃取是中性配位。 相似文献
954.
955.
In this paper, we presented a novel, rapid and highly sensitive sensor for glutathione (GSH), cysteine (Cys) and histidine (His) based on the recovered fluorescence of the carbon quantum dots (CQDs)–Hg(II) system. The CQDs were synthesized by microwave-assisted approach in one pot according to our previous report. The fluorescence of CQDs could be quenched in the presence of Hg(II) due to the coordination occurring between Hg(II) and functional groups on the surface of CQDs. Subsequently, the fluorescence of the CQDs–Hg(II) system was recovered gradually with the addition of GSH, Cys or His due to their stronger affinity with Hg(II). A good linear relationship was obtained from 0.10 to 20 μmol L−1 for GSH, from 0.20 to 45 μmol L−1 for Cys and from 0.50 to 60 μmol L−1 for His, respectively. This method has been successfully applied to the trace detection of GSH, Cys or His in human serum samples with satisfactory results. The proposed method was simple in design and fast in operation, which demonstrated great potential in bio-sensing fields. 相似文献
956.
Zhen Long Dongping Yu Yanfang Liu Nana Du Yanduo Tao Lijuan Mei Zhimou Guo Xinmiao Liang 《Analytica chimica acta》2015
This study investigated the influence of organic sample solvents on separation efficiency of basic compounds under strong cation exchange (SCX) mode. The mixtures of acidic aqueous solution and organic solvent such as acetonitrile, ethanol, methanol and dimethyl sulfoxide (DMSO) were tested as sample solvents. For later-eluting analytes, the increase of sample solvent elution strength was responsible for the decrease of separation efficiency. Thus, sample solvents with weak elution strength could provide high separation efficiencies. For earlier-eluting analytes, the retention of organic sample solvents was the main factor affecting separation efficiency. Weakly retained solvents could provide high separation efficiency. In addition, an optimized approach was proposed to reduce the effect of organic sample solvent, in which low ionic solvent was employed as initial mobile phase in the gradient. At last, the analysis of impurities in hydrophobic drug berberine was performed. The results showed that using acidic aqueous methanol as sample solvents could provide high separation efficiency and good resolution (R > 1.5). 相似文献
957.
Li Yuanchao Xu Guangri Fan Shumin Ma Jingjing Shi Xiaohui Long Zaixin Deng Wenjie Fan Wenxiu Yang Shuting 《Journal of Solid State Electrochemistry》2020,24(4):821-828
Journal of Solid State Electrochemistry - Synthesis method is crucial to the improved electrochemical performances of LiMnPO4 materials with poor electronic and ionic conductivity for large-scale... 相似文献
958.
Yunong Li Lei Wang Jingxiang Low Di Wu Canyu Hu Wenbin Jiang Jun Ma Chengming Wang Ran Long Li Song Hangxun Xu Yujie Xiong 《中国化学快报》2020,31(1):231-234
Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions.Herein,aza-fused7 r-conjugated microporous polymer(aza-CMP)with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation.The AuPd nanoparticles anchored on aza-CMP(aza-CM P/Au_xPdy)exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm^2 light irradiation.The improved catalytic performance by the aza-CMP/Au_xPdy is attributed to the unique photothermal effect induced by aza-CMP,which can promote the catalytic benzyl alcohol oxidation occurring at Au Pd.This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect. 相似文献
959.
A novel fluorinated chain extender, (1‐(ethyl(2‐hydroxyethyl)amino)‐3‐ ((3,3,4,4,5,5,6,6,7,7,8,8,8‐tridecafluorooctyl)oxy)propan‐2‐ol) (FPO), was synthesized and characterized by nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), and elemental analysis. Poly (ether urethane)s containing various amounts of the chain extender with fluorinated side chains (FPUs) were prepared by isophorone diisocyanate (IPDI), polytetra‐methylene‐ether‐glycol (PTMG), 3‐aminopropyltriethoxysilane (KH‐550), and 1,4‐butandiol (BDO). Films of FPUs were investigated by water absorption, contact angle, pencil hardness, adhesive force, and thermal analysis. Coating FPUs on micro‐nano concave‐convex structure plate realizes superhydrophobic performance. Scanning electron microscope (SEM) and atomic force microscopy (AFM) demonstrated that there is a lot of irregular concave‐convex structure, which forms a typical air cushion model. X‐ray photoelectron spectroscopy (XPS) analysis showed that surface fluorine content is 165% more than that of film average fluorine content. The superhydrophobic plate with 10% or higher F‐containing FPUs coating is of outstanding chemical corrosion resistance, excellent solvent resistance, and wear resistance. 相似文献
960.
Rongying Liu Dr. Zdravko Kochovski Long Li Yue-wen Yin Jing Yang Guang Yang Guoqing Tao Anqiu Xu Ensong Zhang Prof. Dr. Hong-ming Ding Prof. Dr. Yan Lu Prof. Dr. Guosong Chen Prof. Dr. Ming Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9704-9710
A protein Pascal triangle has been constructed as new type of supramolecular architecture by using the inducing ligand strategy that we previously developed for protein assemblies. Although mathematical studies on this famous geometry have a long history, no work on such Pascal triangles fabricated from native proteins has been reported so far due to their structural complexity. In this work, by carefully tuning the specific interactions between the native protein building block WGA and the inducing ligand R-SL , a 2D Pascal-triangle lattice with three types of triangular voids has been assembled. Moreover, a 3D crystal structure was obtained based on the 2D Pascal triangles. The distinctive carbohydrate binding sites of WGA and the intralayer as well as interlayer dimerization of RhB was the key to facilitate nanofabrication in solution. This strategy may be applied to prepare and explore various sophisticated assemblies based on native proteins. 相似文献