近期热点文章北大核心CSCD

关键词：Na＋活性·化学电源Operando研究方法Q. Li, Z. Liu, F. Zheng, R. Liu, J. Lee, G. Xu, G.Zhong, X. Hou, R. Fu, Z. Chen, K. Amine, J. Mi, S.Wu, C. P. Grey, Y. Yang. Identifying the Structural Evolution of the Na-Ion Battery Na2Fe PO4F Cathode,Angew. Chem. Int. Ed., 10.1002/anie.201805555.厦门大学杨勇教授和合作者采用原位高能XRD、固态NMR和DFT理论方法,研究了Na2FePO4F阴极材料循环过程中晶体结构的动态变化,发现存在两种Na＋晶格位点,但只有一种有电化学活性.化学电源中的Operando研究方法为揭示电极活性物质的构效关系和反应机理提供了有力工具.     

近期热点文章

正Size-Dependent Surface Phase Change of Lithium Iron Phosphate during Carbon Coating J.Wang,J.Yang,Y.Tang,J.Liu,Y.Zhang,G.Liang,M.Gauthier,Y.K.Chen-Wiegart,M.N.Banis,X.Li,R.Li,J.Wang,T.K.Sham,X.Sun Nature Commun.DOI:10.1038/ncomms4451发现LiFePO4包碳过程的界面相变与活性物质的粒径有关,纳米粒子的界面稳定性较高,而微米粒子在高温包碳过程中界面发生明显变化.     

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<正>Size-Dependent Electrocatalytic Reduction of CO2 over Pd Nanoparticles D.Gao,H.Zhou,J.Wang,S.Miao,F.Yang,G.Wang,J.Wang,X.Bao J.Am.Chem.Soc.DOI:10.1021/jacs.5b00046CO2还原反应Pd纳米催化剂的粒度效应.发现3.7nm时CO产率可达91.2%.     

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<正>Graphene,Related Two-Dimensional Crystals,and Hybrid Systems for Energy Conversion and Storage F.Bonaccorso,L.Colombo,G.Yu,M.Stoller,V.Tozzini,A.C.Ferrari,R.S.Ruoff,V.Pellegrini Science DOI:10.1126/science.1246501关于石墨烯用于能量转化与储存的综述.引用了138篇参考文献.     

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TiO2 Microboxes with Controlled Internal Porosity for High-Performance Lithium Storage X. Gao, G. Li, Y. Xu, Z. Hong, C. Liang, Z. Lin Angew. Chem. Int. Ed. DOI: 10.1002/anie.201506357 合成由TiO2纳米棒构成的纳米多孔结构,用作锂离子电池阳极材料,循环300周仍具有187 mAh?g-1的容量,且可20C高倍率放电. Highly Efficient Electrochemical Reduction of CO2 to CH4 in Ionic Liquid Using Metal-Organic Framework Cathode X. Kang, Q. Zhu, X. Sun, J. Hu, J. Zhang, Z. Liu, B. Han Chem. Sci. DOI: 10.1039/C5SC03291A 在碳纸表面沉积含Zn的金属有机框架（MOF）化合物,该电极可高效催化CO2电还原为CH4.     

纳米晶Sb掺杂SnO2(ATO)粉体的合成与表征

以Sn粉和Sb₂O₃为原料.采用共沉淀法制备了纳米ATO粉.TG-DSC及FTIR结果表明.450℃以前前驱体已失去全部水分.并完全转化为氧化物.XRD测量结果表明.所得ATO粉具有四方金红石结构.500℃焙烧后粉体的粒径为12nm.随着焙烧温度的升高.粉体的粒径增加.TEM测定结果表明,粉体的分散性很好.团聚很少.粉体的烧结性能良好,950℃时烧结5h即达到理论密度的97.3％.用霍尔系数法测定粉体的导电行为.表明该粉体具有良好的导电性能.     

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正Suppression of Lithium Dendrite Growth Using Cross-Linked Polyethylene/Poly(ethylene oxide)Electrolytes:A New Approach for Practical Lithium-Metal Polymer Batteries R.Khurana,J.L.Schaefer,L.A.Archer,G.W.Coates J.Am.Chem.Soc.DOI:10.1021/ja502133j将聚乙烯和聚氧乙烯的交联共聚物用作金属锂电池隔膜,不仅获得较高的离子电导率,还可抑制锂枝晶的生长.     

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正Metal-Free Dihydrogen Oxidation by a Borenium Cation:A Combined Electrochemical/Frustrated Lewis Pair Approach E.J.Lawrence,T.J.Herrington,A.E.Ashley,G.G.Wildgoose Angew.Chem.Int.Ed.DOI:10.1002/anie.201405721以一种含硼杂环分子为电子传递媒介,催化有机介质中的氢氧化反应(HOR).Exfoliation of Layered Double Hydroxides for Enhanced Oxygen Evolution Catalysis F.Song,X.Hu Nature Commun.DOI:10.1038/ncomms5477     

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正A New Rechargeable Sodium Battery Utilizing Reversible Topotactic Oxygen Extraction/Insertion of CaFeOz(2.5≤z≤3)in An Organic Electrolyte M.Hibino,R.Harimoto,Y.Ogasawara,R.Kido,A.Sugahara,T.Kudo,E.Tochigi,N.Shibata,Y.Ikuhara,N.Mizuno J.Am.Chem.Soc.DOI:10.1021/ja411365z以CaFeO3为正极材料,充电时CaFeO3还原为CaFeO2.5,释放出来的O与Li+或Na+生成氧化物.     

CTMAB对反相高效液相色谱-电化学检测法测定水中痕量酚类化合物的增敏、增稳作用

研究了阳离子表面活性剂CTMAB对高效液相色谱 -电化学检测法测定水中痕量酚类化合物的增敏、增稳作用。流动相中CTMAB的最佳浓度为 0 .80mmol/L。使用NucleosilC8色谱柱 (2 0 0mm× 4 .6mmi.d .) ,流动相为甲醇 - 0 .0 2 5mol/L邻苯二甲酸氢钾缓冲液 (体积比为 6 0∶4 0 ,pH =5 .0 ,含 0 .0 6mmol/LEDTA、0 .80mmol/LCTMAB)。该方法测定苯酚、4 氯苯酚、2 ,4 二氯苯酚、2 ,4 ,5 三氯苯酚的线性范围分别为 0 .10～ 15 .0 0、0 .15～ 12 .5 0、0 .15～ 2 2 .5 0、0 .30～ 5 0 .0 0 μg/mL ,检出限分别为 0 .0 0 8、0 .0 10、0 .0 16、0 .0 34μg/mL ,测定结果的相对标准偏差分别为 7.0 %、7.2 %、6 .0 %、7.0 % ,回收率分别为 4 8.0 %、80 .0 %、76 .0 %、85 .0 %。     

New strategy for the construction of a monotetrahydrofuran ring in Annonaceous acetogenin based on a ruthenium ring-closing metathesis: application to the synthesis of Solamin

An original convergent total synthesis of Solamin (type A annonaceous acetogenin) was achieved. The central THF core was obtained by means of a ring-closing metathesis (RCM) reaction using a ruthenium imidazolylidene complex. The RCM substrate was prepared from a vinyl-substituted epoxide by reaction with an allyl alcohol, both synthesized from propargylic alcohol. The flexibility of the strategy should be useful in preparing various natural and unnatural annonaceous acetogenins.     

Synthesis of a Mimicking Hybrid of Annonaceous Acetogenin with Steroid for Antitumoral Activity Investigation

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｅｐａｓｔｔｗｏｄｅｃａｄｅｓ ,ａｌａｒｇｅｆａｍｉｌｙｏｆｎａｔｕｒａｌｐｒｏｄｕｃｔｓｎａｍｅｄａｎｎｏｎａｃｅｏｕｓａｃｅｔｏｇｅｎｉｎｓｗｅｒｅｉｓｏｌａｔｅｄａｎｄｃｈａｒａｃｔｅｒｉｚｅｄｂｙｔｈｅｇｌｏｂａｌｒｅｓｅａｒｃｈｅｒｓｆｒｏｍｖａｒｉｏｕｓｓｐｅｃｉｅｓｏｆｔｈｅｐｌａｎｔａｎｎｏｎａｅａｅ .1Ａｍｏｎｇｏｖｅｒ 4 0 0ｍｅｍ ｂｅｒｓ,ｍｏｓｔｏｆｔｈｅｍｗｅｒｅｆｏｕｎｄｔｏｓｈｏｗｐｏｔｅｎｔｃｙｔｏｔｏｘｉｃａｎｄａｎｔｉｔｕｍｏｒａ…     

Mimicry of annonaceous acetogenins: enantioselective synthesis of a (4R)-hydroxy analogue having potent antitumor activity

The (4R)-hydroxylated analogues of annonaceous acetogenin mimicking compound 2 were designed and synthesized structurally on the basis of the naturally occurring annonaceous acetogenin bullatacin, which was discovered as a typical member of the novel family of polyketides with potent cytotoxicity, antitumoral, and other biological activities. The preliminary screenings show that the IC(50) values of 2 were 1.6 x 10(-3) and 8 x 10(-2) microg/mL against HT-29 and HCT-8, respectively. A remarkable enhancement effect was observed by the activity comparison of 1c and its (4R)-hydroxylated analogue 2.     

Stereoselective synthesis of bis-hydroxy-tetrahydrofurans using cross metathesis

A short asymmetric approach for the synthesis of bis-tetrahydrofuran units of various annonaceous acetogenins is described. The key steps of the synthesis are self-cross metathesis and Sharpless asymmetric dihydroxylation.     

Enantioselective total synthesis of the potent antitumor agent (-)-mucocin using a temporary silicon-tethered ring-closing metathesis cross-coupling reaction

The enantioselective total synthesis of the annonaceous acetogenin (-)-mucocin (1) was accomplished using a triply convergent 12-step sequence (longest linear sequence) in 13.6% overall yield. This represents the first application of the temporary silicon-tethered (TST) ring-closing metathesis (RCM) cross-coupling reaction and the enantioselective alkyne/aldehyde addition to the synthesis of a complex annonaceous acetogenin. Moreover, all three fragments required for the coupling reactions are conveniently prepared in 5-6 steps from two readily available enantiomerically enriched epoxides. Finally, this synthesis stimulated the development of a new approach for the construction of 3-hydroxy-2,6-disubstituted tetrahydropyrans, using the bismuth tribromide-mediated reductive etherification reaction, which represents a motif that is prevalent in a wide range of pharmacologically significant natural products.     

Atemoyacin A: A new bis-tetrahydrofuranyl annonaceous acetogenin from Annona atemoya H.

Atemoyacin A, a new annonaceous acetogenin was isolated from the alcoholic extract of the seeds of Annona atemoya Hort (Annonaceae). Its structure and relative configuration were elucidated on the basis of the spectral analysis.     

天然番荔枝内酯类化合物构效关系研究进展

番荔枝内酯类化合物化学结构及抗肿瘤作用机制独特.综述了这类天然化合物的构效关系研究进展.     

紫玉盘种子中的番荔枝内酯成分研究I. 紫玉盘素(Microcarpacin)的分离及结构鉴定

从紫玉盘(Uvaria microcarpa Champ. ex Benth)种子中首次分离得到一个新的邻双四氢呋喃环番荔枝内酯(Annonaceousacetogenin)化合物-紫玉盘素(Microcarpacin)。同时首次以纯化合物形式分离得到两个已知的番荔枝内酯Narumicins I和Narumicins II.     

NMR determination of absolute configuration of butenolides of annonaceous type

We report herein the first determination of the absolute configuration of the annonaceous butenolides by a NMR method. This technique uses a chiral solvating agent (CSA), the so-called Pirkle's reagent, at low temperature and low concentration, allowing one to apply this method to other natural products as well. Indeed, the presence of basic sites (e.g. tetrahydrofuran, hydroxyl) did not interfere with the major solvation of the reagent with the lactone moiety. A new model is proposed which allowed us to confirm the (S) absolute configuration of the butenolide of annonaceous acetogenins. Furthermore this method can be successfully applied to the measure of the diastereomeric (or enantiomeric) excess of the same butenolide containing compounds.     

牛心果化学成分的研究

从牛心果(Annona glabra Linn)树皮中, 分离到三个白色蜡状固体, 经光谱分析, 它们分别为 强抗肿瘤活性番荔枝内酯(annonaceous acetogenin) 化合物-----annonacin,corossolone和solamin.