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采用^1H NMR谱、^13C NMR谱、DEPT(θ=3π/4)谱、红外吸收光谱、质谱等仪器分析手段确证了4种新合成的有机光致变色材料螺E嗪化合物的结构,并对化合物的^13C NMR谱化学位移和质谱碎片进行了归属和确认。 相似文献
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分别以不同的异羟肟酸为配体,合成了3个氧钒(Ⅳ)配合物,运用元素分析、红外光谱、核磁共振谱(^1H NNR,^13C NMR,^51V NMR)、电子顺磁共振和电子吸收光谱等测试手段对配合物进行了表征.分别在不同的羟基醇中以氧钒(Ⅳ)配合物阱BHAOV为基础,合成了2个含烷氧基的五价氧钒(Ⅴ)化合物.在吡啶中合成了含吡啶的六配位氧钒(Ⅳ)配合物阱BHAOV(PY),Ⅴ占据第6位置S原子,可使其不被氧原子进攻而氧化,要使Ⅴ内层发生氧化,在四价钒上至少有一个空的配位位点是完全必要的.而且还研究了BHAOV在乙腈中的配位反应动力学. 相似文献
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合成了八种新的四氟硼酸二甲基苯基锍,用元素分析和核磁共振对其结构进行了表征。研究了以CDCl~3为溶剂,NMR位移试剂Eu(fod)~4^-对所合成锍盐的^1H和^1^3C NMR的影响。结果表明,Eu(fod)~4^-是一个对锍盐非常有效的位移试剂,且Eu(fod)~4^-对二甲基苯基锍盐之甲基的^1H和^1^3C NMR的位移呈线性关系。 相似文献
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以5-羟甲基糠醛及其加成产物为原料,用化学或电化学合成法合成了标题化合物,其产物结构经元素分析,IR和^1H NMR确证。 相似文献
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ω-溴代芳香基乙酮与3-(D-葡萄糖-1-基)-4-氨基-5-巯基-1,2,4-三唑反应 合成了一系列新颖的3-(D-葡萄糖-1-基)-6-芳基-7H-1,2,4三唑并[3,4-b[1,3 ,4]噻二嗪.用元素分析,IR,NMR,MS对其结构进行了表征,研究了其NMR波谱特 征,并以^1H-^1H COSY,^13C-^1H COSY,COLOC二维NMR技术对其^1H NMR,^13C NMR的谱峰进行了全归属 相似文献
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Yue Jun Zhu~a Ye Bang Tan~ 《中国化学快报》2008,19(3):355-358
Novel double hydrophilic block copolymers with amine pendant chains were synthesized by polymerization of 4-vinyl benzylamine hydrochloric salt using 4,4′-azo-bis[4-cyanopentanoate poly(ethylene glycol) ester] as macroazoinitiator. The structures of the copolymers were characterized by ^1H NMR, FTIR spectra and acid-base titration, GPC-MALS techniques. 相似文献
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Shin-ichi Yusa Megumi Shibata Masamitsu Noborizato 《Journal of Dispersion Science and Technology》2013,34(2):287-292
Heat and salt induced aggregation of three well-defined double hydrophilic block copolymers (DHBCs) of sodium 2-(acrylamido)-2-methylpropanesulfonate (AMPS) and N-isopropylacrylamide (NIPAM) with constant chain length of the PAMPS block (with number-average degree of polymerization, DP n = 61) and varying chain length of the PNIPAM block with DP n = 11, 23, and 34 synthesized via reversible addition-fragmentation chain transfer (RAFT) controlled radical polymerization was investigated by turbidity, dynamic light scattering (DLS) and 1H NMR measurements. In the presence of salt or with an increase in temperature, the diblock copolymers form micelles with a PNIPAM core and PAMPS corona. The heat and salt induced aggregation in dilute aqueous solutions dependant on the molecular characteristics of the DHBC (DP n of the PNIPAM block) was observed. The DHBC becomes amphiphilic as the PNIPAM block loses hydrophilicity at higher temperature above its lower critical solution temperature (LCST). Furthermore, the presence of salt induces salting out effect of the uncharged PNIPAM block. The diblock copolymer thus forms nanosized aggregates at a high temperature or in the presence of salt. These aggregates may be multiple aggregates due to inter-micellar aggregation of the spherical core-corona micelles. 相似文献
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Wolfgang von Philipsborn 《Angewandte Chemie (International ed. in English)》1971,10(7):472-490
In double resonance spectra, transitions between energy levels of a nuclear spin system are measured in the presence of two (or more) oscillating magnetic fields. Experiments of this nature form the basis of what is nowadays one of the most important techniques of NMR spectroscopy. Depending on the method selected, they can be used to unravel complex spectra, to measure hidden or weak resonances, or to determine the relative signs of coupling constants, as well as in stereochemical or kinetic studies. This wide and steadily growing range of applications of double resonance is described with the aid of specifilc examples. 相似文献
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We present a theoretical and numerical modeling study of the multiphysicochemical process in electrokinetic transport in silica nanochannels. The electrochemical boundary condition is solved by considering both the chemical equilibrium on solid-liquid interfaces and the salt concentration enrichment caused by the double layer interaction. The transport behavior is modeled numerically by solving the governing equations using the lattice Poisson-Boltzmann method. The framework is validated by good agreements with the experimental data for all range of ionic concentrations. The modeling results suggest that when the double layers interact, the bulk salt concentration enrichment results in the saturation of conductances for low ionic concentrations. Both the streaming conductance and the electrical conductance are enhanced by the double layer interaction, and such enhancements diminish when the channel size is larger than 10 times of the Debye length. The streaming conductance increases with pH almost linearly when pH < 8, while the electrical conductance increases with pH exponentially. 相似文献
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孔凡丽 《中国无机分析化学》2018,8(4):56-60
复杂高铋物料中,铋、砷、锑、锡四元素含量高且共存时会影响铅的测定。特别是铋含量高时对铅的测定影响大。实验用EDTA—酒石酸联合掩蔽铋、砷、锑、锡,在稀硫酸介质中以硫酸钾为沉淀剂,使铅生成硫酸铅钾复盐沉淀而与铋、砷、锑、锡、铁、铜、锌、铝、钴、镍等干扰离子分离,沉淀以乙酸-乙酸钠浸取,二甲酚橙为指示剂,Na2EDTA滴定法测定铅。试验进一步优化了测定条件,确定最佳条件:硫酸(1 1)加入量为7mL、硫酸钾用量为5g、煮沸时为5min、沉淀陈化时间为2h、EDTA 50g/L 加入量为10mL、酒石酸用量为0.5g,铅的回收率99.70% ~100.65%。将实验方法应用于测定复杂高铋物料中铅,标样BY0111-1与给定值一致,相对标准偏差(n=11)RSD 0.20%~0.23%,满足生产测试要求。 相似文献
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M. Sc. Benedikt Ritschel Dr. Jordi Poater B. Sc. Hannah Dengel Prof. Dr. F. Matthias Bickelhaupt Dr. Crispin Lichtenberg 《Angewandte Chemie (International ed. in English)》2018,57(14):3825-3829
The transformation of C?H bonds into more reactive C?M bonds amenable to further functionalization is of fundamental importance in synthetic chemistry. We demonstrate here that the transformation of neutral bismuth compounds into their cationic analogues can be used as a strategy to facilitate CH activation reactions. In particular, the double CH activation of bismuth‐bound diphenyl amide, (NPh2)?, is reported along with simple one‐pot procedures for the functionalization of the activated positions. The organometallic products of the first and second CH activation steps were isolated in high yields. Analysis by NMR spectroscopy, single‐crystal X‐ray diffraction, and DFT calculations revealed unusual ground‐state properties (e.g., ring strain, moderate heteroaromaticity), and provided mechanistic insight into the formation of these compounds. 相似文献
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H. Hodjat-Kachani A. Lattes J.J. Perie J. Roussel 《Journal of organometallic chemistry》1975,96(2):175-182
The products obtained by addition of mercuric salt to olefinic nitriles are interpreted on the basis of a chelation by the mercuric salt of the double bond and nitrile group.The mercurinium intermediate thus stabilized was characterized by NMR spectroscopy. 相似文献
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螺环原碳酸酯的单体合成及阳离子聚合袁金颖(合肥工业大学化工学院,合肥230009)潘才元白如科(中国科学技术大学材料科学与工程系,合肥230026)关键词合成螺环原碳酸酯阳离子聚合双开环聚合反应中图分类号O523.624Bailey于1972年发现,... 相似文献
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本文简要介绍了二维双量子魔角旋转核磁共振(DQ-MAS NMR)新技术的基本原理,详细综述了1H、19F、29Si、31P、19F和27Al DQ-MAS NMR技术在各种固体功能材料中的应用,并展望了该技术的应用前景. 相似文献