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1.
稀土、2-羟基-3-萘甲酸、邻菲咯啉三元配合物合成及表征   总被引:6,自引:0,他引:6  
在乙醇溶液中合成了稀土离子(RE=Tb,Eu,Sm,Nd)与2-羟基-3-萘甲酸(HL)、邻菲咯啉(phen)固体配合物.通过元素分析、红外光谱、紫外光谱、差热-热重分析,确定了配合物的组成为REL4·phen2·Na·H2O.初步研究了这些配合物的谱学性质并推测出羧基(-COO-)与稀土离子和钠离子属于桥式配位,形成了链状结构的化合物.其中钠离子和稀土离子分别为六配位和八配位模式.  相似文献   

2.
本文研究了八个新化合物-氨基酸、肽-雌甾衍生物的13C-NMR谱,讨论了谱蜂的特征,并借助于13C-NMR谱确证了此类新化合物的形成。  相似文献   

3.
研究了最近合成的6种N-(2-苯基-1,2,3-连三唑-4-甲酰基)-N′-芳基硫脲新化合物. 通过测定6种新化合物的13C NMR和DEPT谱等,对其结构进行了确定,并对其全部谱峰做出归属; 并给出了这类新化合物中苯的两个新取代基(-R1 和-R2 )的取代参数; 同时,讨论了化学位移与分子结构间的一些关系.  相似文献   

4.
胡蕾  聂丽  李少志  宋洪强 《光谱实验室》2012,29(5):3208-3211
以对溴苯胺和2-烯丙醛为原料,通过Skraup环化反应合成6-溴喹啉,进而与α-苯丙氨酸作用,采用不同方法合成了N-6-喹啉基-α-苯丙氨酸.探讨了微波辐射时间、辐射功率及缚酸剂种类等对合成产率的影响,最佳条件下产率可达94.5%.目标化合物的结构通过1H NMR、IR、元素分析和紫外光谱等方法进行了表征,紫外光谱研究表明:目标化合物的吸收波长红移,强度增加.  相似文献   

5.
采用色谱法从蒲儿根花部位中分离得到2-甲基-6-(2-甲苯基)-2-庚烯,该化合物第一次以单体的形式得到,通过测定氢-氢相关谱(1H-1H COSY)、DEPT谱、异核单量子相关谱(HSQC)及异核多键相关谱(HMBC)等二维谱确定了该化合物的结构,并对该化合物的1H NMR和13C NMR谱进行了归属.  相似文献   

6.
研究了最近合成的6种N-(2-苯基-1,2,3-连三唑-4-甲酰基)-N′-芳基硫脲新化合物. 通过测定6种新化合物的13C NMR和DEPT谱等,对其结构进行了确定,并对其 全部谱峰做出归属;并给出了这类新化合物中苯的两个新取代基(R1 和R2 )的取代参数;同时,讨论了化学位移与分子结构间的一些关系.  相似文献   

7.
合成了铕、铽-2-噻吩甲酸的二元配合物和铕、铽-2-噻吩甲酸-2,2′-联吡啶的三元配合物,并对它们进行了元素分析、稀土络合滴定、摩尔电导测定,确定了配合物组成分别为REL3.2H2O及REL3 L′.C2H5OH(RE=Eu,Tb;L=2-噻吩甲酸、L′=2,2′-联吡啶),测定了配体及配合物的IR谱、1H NMR谱及荧光光谱。IR谱和1H NMR谱测定表明,配体2-噻吩甲酸羧基氧、配体邻菲咯啉2个氮原子与稀土离子配位。荧光光谱实验表明,高氯酸铕和高氯酸铽分别与2,2′-联吡啶和2-噻吩甲酸反应形成的三元配合物的荧光明显强于二元配合物。  相似文献   

8.
我们合成有机锗化合物的重要中间体 4-三氯锗基 - 4-甲基 - 2 -戊酮 ( A)、3-三氯锗基 -3,5,5-三甲基环己酮 ( B)、2 -三氯锗基 - 2 -苯基乙基苯基酮 ( C)、2 -三苯基锗基乙基苯基酮 ( D) ,测量了他们的 Raman和 IR光谱并进行了讨论。在化合物 A- D的 Raman和 IR光谱 ,苯环中的 C- H伸缩振动 ,饱和 C- H伸缩振动 ,饱和 Ge- C伸缩振动等特征数据基本一致。C=O伸缩振动在 Raman和 IR光谱中位置基本一致 ,但在红外光谱中均为强吸收带 ,而在 Raman光谱中的峰强度差别则非常大 ,化合物 A、D的峰非常弱 ,而 C的峰则很强 ,化合物 A- C的 Ge- Cl振动均在 390 cm- 1附近出现强峰。  相似文献   

9.
利用Bogoliubov理论研究了自由空间中可调自旋-轨道耦合玻色-爱因斯坦凝聚体(Bose-Einstein condensates, BECs)的激发谱.通过高频近似得到具有两体相互作用时与时间无关的有效Floquet哈密顿量,从而获得一种可调的自旋-轨道耦合和一种可由周期驱动拉曼耦合调控的有效两体相互作用.基于系统有效的Floquet哈密顿量,得到凝聚体具有相互作用时的色散关系,发现周期驱动强度可以有效地调控色散关系的结构,即周期驱动的拉曼耦合可以调控系统在零动量相与平面波相之间的相变.进一步利用Bogoliubov理论得到系统的Bogoliubov-de-Gennes (BdG)方程,分别研究了凝聚体在零动量相和平面波相中的激发谱.发现零动量相中的激发谱均为声子激发,且激发谱随周期驱动强度的增加表现出贝塞尔函数的行为;平面波相中的激发谱存在声子激发和旋子激发,当周期驱动强度增加时,旋子模出现软化现象.因此,可以通过周期驱动拉曼耦合实时地调控自旋-轨道耦合BECs激发谱中的声子激发和旋子激发.  相似文献   

10.
研究了螺双杯[4]芳烃-冠-3醚在溶液状态下的1H、13C、1H-13C HMQC、1H-13C HMBC、1H-1H TOCSY等核磁共振谱,对其1H、13C谱进行了归属,确定了室温该化合物在溶液状态下的稳定构象为锥式,并利用2D NOESY近似求出杯芳烃区的各种氢的距离,以此为约束进行了模拟淬火计算,证实了2D NOESY谱中多种羟基存在方式,并利用二维交换矩阵计算得出几种羟基的交换速率及其与溶剂中痕量水的交换速率.  相似文献   

11.
Experimental and ab initio results that demonstrate the effect of stress on the nuclear magnetic resonance spectra of materials are shown. The design of a cell that generates uniaxial compressive stress is presented, and results on gallium phosphide and lead nitrate single crystals that illustrate the observable results of the stress are shown. Tensors that relate stress and strain to changes in the chemical shielding tensors and the electric field gradient tensors are defined formally. The elements of these tensors are then computed by a density functional theory approach that makes use of planewaves and pseudopotentials. The experimental results are interpreted with the aid of the calculations. Extensions to spinning samples and to the interpretation of optical phenomena in materials are discussed.  相似文献   

12.
Many alternative processing techniques have recently been proposed in the literature. Most of these techniques rely on specific acquisition protocols as well as on specific data processing techniques, the need for an efficient versatile and expandable NMR processing tool would be a particularly timely addition to the modern NMR spectroscopy laboratory. The work presented here consists in a modeling of the various possible NMR data processing approaches. This modeling presents a common working frame for most of the modern acquisition/processing protocols. Two different data modeling approaches are presented, strong modeling and weak modeling, depending whether the system under study or the measurement is modeled. The emphasis is placed on the weak modeling approach. This modeling is implemented in a computer program developed in python and called NPK standing (standing for NMR Processing Kernel), organized in four logical layers (i) mathematical kernel; (ii) elementary actions; (iii) processing phases; (iv) processing strategies. This organisation, along with default values for most processing parameters allows the use of the program in an unattended manner, producing close to optimal spectra. Examples are shown for 1D and 2D processing, and liquid and solid NMR spectroscopy. NPK is available from the site: http://abcis.cbs.cnrs.fr/NPK.  相似文献   

13.
《光谱学快报》2013,46(3):319-342
Abstract

The application of nuclear magnetic resonance (NMR) spectroscopy, hyphenated NMR, and diffusion‐ordered spectroscopy (DOSY) to the characterization of mango juice, as an example of a complex food mixture, is described. The compositional changes taking place as a function of ripening were followed, and selected metabolites were quantified by integration of the corresponding NMR peaks. In this way, an overall view of the metabolite changes is obtained, enabling the study of the biochemical mechanisms involved in the ripening process. More than 50 compounds were identified by 1D‐ and 2D‐NMR, but many ambiguous assignments remain due to spectral overlap or insufficient coupling information. The use of Liquid Chromatography (LC‐NMR) and LC‐NMR/Mass Spectrometry (MS) enables a fuller characterization of the soluble pectin fraction to be made; its dependence on ripening stage is discussed. Finally, DOSY adds information on the Mr of many metabolites, including the pectin fractions of ripe and unripe mango juices, and enables further peak assignments to be made.  相似文献   

14.
几种N-取代马来酰胺酸辅酶模型的核磁共振研究   总被引:1,自引:0,他引:1  
我们对8种N-取代马来酰胺酸辅酶模型与不同类型的亲核试剂反应后生成的产物进行了1H、13C NMR的研究, 测得1H、13C谱化学位移,研 究探讨其规律性, 并测试了IR谱和元素分析.  相似文献   

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Recently, it was demonstrated that pseudo-chromatographic NMR experiments could be performed using typical chromatographic solids and solvents. This first setup yielded improved separation of the spectral components of the NMR spectra of mixtures using PFG self-diffusion measurements. The method (dubbed Chromatographic NMR) was successively shown to possess, in favorable cases, superior resolving power on non-functionalized silica, compared to its LC counterpart. To further investigate the applicability of the method, we studied here the feasibility of Chromatographic NMR in common deuterated solvents. Two examples are provided, using deuterated chloroform and water, for homologous compounds soluble in these solvents, namely aromatic molecules and alcohols, respectively.  相似文献   

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18.
We report new measurements of NMR parameters for 71Ga in gallium bearing oxide reference compounds, ranging from perfectly ordered systems to disordered crystalline structures and their aluminate counterparts. Static, MAS, and QPASS spectra are obtained at magnetic fields ranging from 7.0 to 18.8 T. With these results we enhance the previously established correlation between isotropic chemical shifts of 71Ga and 27Al and propose a correlation between gallium and aluminum electric field gradients (EFG). This correlation shows that the EFG at 71Ga sites are generally three times greater than those at equivalent 27Al sites.  相似文献   

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