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1.
本文研究了5-(α-萘)-四唑(Ⅱ),5-(α-萘)-2H-四唑-2-乙酸甲酯(Ⅲ),5-(α-萘)-2H-四唑-2-乙酰肼(Ⅳ),1-[5-(α-萘)-2H-四唑-2-乙酰]-4-苯基氨基硫脲(V)以及3-[5-(α-萘)-2H-四唑-2-甲撐]-4-苯基-1,2,4-三唑啉-5-硫酮(Ⅵ)的13C核磁共振谱和各种13C-NMR化学位移。根据化学位移理论、讯号强度以及同模型化合物化学位移的比较,辨认其归属。  相似文献   

2.
化学发光法测定水中1-溴-3-氯-5,5-二甲基海因   总被引:1,自引:1,他引:0  
基于在碱性条件下 (p H 12 .0— 12 .5 ) 1-溴 - 3-氯 - 5 ,5 -二甲基海因与鲁米诺 -过氧化氢体系反应产生化学发光的性质 ,建立了一种测定其含量的新方法。 1-溴 - 3-氯 - 5 ,5 -二甲基海因的浓度在 4 .0× 10 -8— 1.0×10 -6mol/ L范围内与化学发光强度呈良好的线性关系。本方法的线性范围宽 ,灵敏度高 ,检出限为 2 .0×10 -8mol/ L。操作简单、方便。应用于游泳池水中 1-溴 - 3-氯 - 5 ,5 -二甲基海因的测定 ,结果令人满  相似文献   

3.
甾体药物(LIVIAL)1在微酸性条件下发生重排反应得另一化合物2.对化合物1,2应用NMR梯度场反相实验(GCOSY,GNOESY,GHMQC和GHMBC)进行深入的NMR研究,归属了化合物1,21H,13C NMR的化学位移.讨论了它们的立体化学及反应历程,并对其进行了计算机分子模拟.  相似文献   

4.
通过对5种2-取代苯基-1,2-二氢-3-哒嗪酮-6-葡萄糖苷的1H NMR和IR谱的分析,确证其糖苷键为β-构型,用1H-1H COSY技术对它们的1H谱峰进行了归属.  相似文献   

5.
利用1H NMR,13C NMR,2DNMR及IR,MS等技术对β-苯甲酰基-γ-取代苯基-γ-丁酸内酯的结构及空间构型进行确证,讨论了该结构的NMR谱学行为,提出了生成该化合物的可能的化学反应历程.  相似文献   

6.
从虎杖(Polygonum cuspidatum Sieb.et Zucc.)抗菌抗炎有效部位中分离得到一化合物:5-羧甲基-7-羟基-2-甲基色原酮. 首次利用2D-NMR技术对其核磁共振信号进行了确切归属.  相似文献   

7.
描述了一种有效的环境友好的“一锅煮”法合成13-乙酰基-9-甲基-11-羰基-8-氧代-10,12-二氮杂三环[7.3.1.0~(2,7)]十三碳-2,4,6-三烯。该法用廉价易得的溴化镁作催化剂,在无溶剂存在下,由起始原料水杨酸,乙酰丙酮和脲通过Biginelli缩合反应伴随着分子内的Michael加成反应一步完成。用核磁共振氢谱、碳谱、飞行时间质谱以及红外光谱数据表征了产物的结构为一氧桥多环化合物,而不是带有自由羟基的二氢嘧啶酮。最后由质谱给出的精确质量及其所代表的元素组成推出了该化合物的质谱裂解途径。  相似文献   

8.
本文报告二十个题目化合物的80兆1H NMR谱。这些新合成的化合物均未见诸文献。利用偶合常数鉴定了β-内酰胺环的立体构型,并对图谱进行了解析,证明所合成的化合物均为顺式构型的β-内酰胺单环衍生物,同时讨论了溶剂和取代基对化学位移的影响。  相似文献   

9.
测定了戊环唑(1)、甲环唑(2)、丙环唑(3)的NMR谱,对其一般特征进行 了对比与讨论,用13C-1H COSY、13C-1H COLOC、DQF-COSY、DEPT等技术对它们的1H、13C NMR谱峰进行了全归属,并应用1H-1H NOESY谱研究其立体结构.
  相似文献   

10.
ZORBAX Eclipse XDB- C8(4.6× 1 5 0 mm,5 μm)色谱柱 ,乙腈流动相 ,流速 0 .6 0 m L/min,检测波长4 2 0 nm,反相高效液相色谱法测定 1 - (4-硝基苯 ) - 3- (5 -溴 - 2 -吡啶 ) -三氮烯。该法的线性范围为 1—1 0 .0 μg/m L,线性回归方程为 A=5 .91 5 4 .4 37C,相关系数 0 .9989,相对标准偏差为 0 .8973%(C=7.2 0 μg/m L,n=5 ) ,检出限为 0 .0 2 872 μg/m L,平均回收率在 93.2 %— 1 0 2 .2 %之间。  相似文献   

11.
12.
Results of radionuclide activity concentration measurements in deposition and ground-level air conducted at the station of the Institute of Physics situated 3.5 km from the Ignalina Nuclear Power Plant (Ignalina NPP) in 2005 are analyzed. Atmospheric depositional fluxes of 7Be, 60Co and 137Cs are estimated. Radionuclide particle deposition rates are calculated. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model of the global dispersion and deposition is used to explain variations in the 137Cs activity concentration in the ground-level air in the Ignalina NPP region in 2005. An increase in the 137Cs activity concentration of up to 17.4 μBq m−3 on 30 October-5 November is studied. Modelling results show that the Chernobyl NPP Unit 4 Sarcophagus and the radiocaesium resuspension from the Chernobyl NPP accident polluted regions are sources of 137Cs to the environment of the Ignalina NPP. Results on solubility in water of aerosols — carriers of 137Cs — are discussed.  相似文献   

13.
It is shown that bulk semiconductors exhibit strongly asymmetric Fano-type resonance profiles in magnetoabsorption processes involving the formation of hot electron-hole pairs (EHPs) and accompanied by the scattering of the EHPs by defects. This result is valid for transitions to electronic states with large Landau quantum numbers, when the Coulomb interaction plays a small role. The physical reason for such a sharp change in the magnetoabsorption coefficient as compared with the expected result for the ordinary density of states in a quantizing magnetic field is that the electronic excitations are quasi-one-dimensional. The form of the resonance absorption is in good qualitative agreement with the experimental data. Pis’ma Zh. éksp. Teor. Fiz. 63, No. 8, 619–622 (25 April 1996)  相似文献   

14.
The solutions of a renormalized BCS equation are studied in three space dimensions in s, p and d waves for finite-range separable potentials in the weak to medium coupling region. In the weak-coupling limit, the present BCS model yields a small coherence length and a large critical temperature, , appropriate for some high- materials. The BCS gap, , and specific heat as a function of zero-temperature condensation energy are found to exhibit potential-independent universal scalings. The entropy, specific heat, spin susceptibility and penetration depth as a function of temperature exhibit universal scaling below in p and d waves. Received: 18 July 1997 / Revised: 8 September 1997 / Accepted: 29 September 1997  相似文献   

15.
The thermal instability of a layer of Rivlin-Ericksen elastico-viscous fluid in porous medium acted on by a uniform magnetic field is considered. For stationary convection, Rivlin-Ericksen elastico-viscous fluid behaves like a Newtonian fluid. The magnetic field is found to have stabilizing effect whereas medium permeability has destabilizing effect. The magnetic field introduces oscillatory modes in the system, A sufficient condition for the non-existence of overstability is also obtained.  相似文献   

16.
We present the action and transformation laws of supergravity in 11 dimensions which is expected to be closely related to the O(8) theory in 4 dimensions after dimensional reduction.  相似文献   

17.
The concepts of uncertainty in prediction and inference are introduced and illustrated using the diffraction of light as an example. The close relationship between the concepts of uncertainty in inference and resolving power is noted. A general quantitative measure of uncertainty in inference can be obtained by means of the so-called statistical distance between probability distributions. When applied to quantum mechanics, this distance leads to a measure of the distinguishability of quantum states, which essentially is the absolute value of the matrix element between the states. The importance of this result to the quantum mechanical uncertainty principle is noted. The second part of the paper provides a derivation of the statistical distance on the basis of the so-called method of support.  相似文献   

18.
19.
In this paper, we investigate the data of industries in China and find that the frequency distributions of fixed assets and fixed-assets’ investment of industries obey power laws. We show that these power-law modes can be explained by the rules of the Simon Model, rather than the existing investment theories such as the classical investment theory or acceleration principle. Moreover, the mechanism of the investment distribution may be similar to the forest-fire model of self-organizing criticality. By introducing the complex system methods, this research changes the traditional opinion of the investment and gains some meaningful understanding in the dynamics of industries and the economic cycle.  相似文献   

20.
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