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1.
含手性轴的季戊四醇双缩醛的NMR研究   总被引:1,自引:1,他引:0  
采用1D和2D梯度场NMR技术(包括1D 1H NMR, 13C NMR, DEPT, 2D 1H-1H COSY, HSQC, HMBC),对3,3′-二(2,4-二氯苯基)-2,4,2′,4′-四氧杂螺[5.5]十一烷的4个亚甲基呈现的4组裂分峰进行了明确的归属,也对化合物中其它1H和13C NMR谱信号进行了全归属,为四氧杂螺双缩醛类化合物的结构鉴定提供了充分依据.  相似文献   

2.
(3R)-4-[(4-甲基苯磺酰基)]-1,4-噻嗪-3-酰基-[(2R)-2-氨基-4-甲基]-戊酸异丙酯(代号:HD5-6),是一个拥有完全自主知识产权的FK506结合蛋白家族(FKBPs)配体,具有显著的促神经再生作用,有望在临床实现对神经退行性疾病和肌萎缩侧索硬化、脑卒中的有效治疗.本文采用多种核磁共振(NMR)技术,包括1H NMR、13C NMR、DEPT、1D NOESY、1H-1H COSY、1H-13C HSQC和1H-13C HMBC等,并结合质谱(MS)、紫外光谱(UV)和红外光谱(IR)等方法对此化合物进行解析,对其1H和13C NMR谱峰进行全归属,通过多种谱学技术确证了该化合物的化学结构.  相似文献   

3.
对雷酚内酯对照品的紫外吸收光谱(UV)、红外吸收光谱(IR)、质谱(MS)、核磁共振(NMR)谱(包括1H NMR、13C NMR、DEPT、1H-1H COSY、NOE、1H-13C HSQC和1H-13C HMBC谱图)进行了分析,对其1H和13C NMR谱峰进行了全归属,纠正了文献[5]的归属错误,确证了雷酚内酯对照品的化学结构.  相似文献   

4.
樊宏宇 《波谱学杂志》2018,35(1):98-108
以连翘脂素和布洛芬为原料,通过Schotten-Baumann酯化合成了酯合物——连翘脂素-布洛芬酯.对其紫外吸收光谱(UV)、红外吸收光谱(IR)、基质辅助激光解吸/电离飞行时间质谱(MALDI-TOF-MS)、1D和2D核磁共振(NMR)波谱(包括1H NMR、13C NMR、DEPT、1H-1H COSY、1H-1H NOESY、1H-13C HSQC和1H-13C HMBC)进行了解析,对其1H和13C NMR谱峰进行了全归属.  相似文献   

5.
以苯并[1,2-b∶4,5-b´]二噻吩-4,8-二酮为原料合成了一种聚合物太阳能电池材料的单体2,6-双(三甲基锡)-4,8-双(2-乙基己氧基)苯并[1,2-b∶4,5-b´]二噻吩. 通过多核1D和2D NMR技术(包括1D 1H、13C、119Sn、117Sn NMR、DEPT、选择性1D TOCSY及2D1H-1H COSY、gHSQC、gHMBC)表征了目标分子结构,完成了 1H、13C、119Sn 与117Sn NMR化学位移归属,并探讨了该化合物的NMR谱线特征.  相似文献   

6.
丁氟螨酯是一种新型杀螨剂,具有高效、低残留的特点.本文对其红外吸收光谱(IR)、紫外吸收光谱(UV)、质谱(MS)及核磁共振(NMR)波谱(包括1H NMR、13C NMR、DEPT、1H-1H COSY、1H-13C HSQC、1H-13C HMBC)进行了测定,分析了其UV和IR谱图特征吸收峰对应的基团,并对其1H和13C NMR信号进行了归属,确证了丁氟螨酯的结构.该研究将为丁氟螨酯的其他相关研究提供参考.  相似文献   

7.
对胃粘膜保护剂依卡倍特钠的紫外吸收光谱(UV)、红外吸收光谱(IR)、高分辨-质谱(HR-MS)、核磁共振(NMR)波谱(包括1H NMR、13C NMR、DEPT、1H-1H COSY、1H-13C HSQC和1H-13C HMBC)数据进行了解析,对其所有的1H和13C NMR谱信号进行了归属,通过多种谱学技术确证了依卡倍特钠的结构.  相似文献   

8.
该文合成了一个新的在医药方面具有潜在应用价值的含苯并咪唑环的酰氨基硫脲化合物,即4-(4-甲氧基苯基)-1-[2-(4-硝基苯氧基甲基)-苯并咪唑-1-基\]甲酰基氨基硫脲,并利用元素分析、IR和NMR对其结构进行了表征. 通过NOESY谱确定了其两种异构体(A和B)的构型,并利用2D NMR技术对它们的1H NMR 和13C NMR谱进行了全归属,给出了相应的偶合常数和两种异构体的含量.  相似文献   

9.
吴达旭  沈旭 《波谱学杂志》1998,15(6):547-550
利用1H-1H COSY,1H-13C HMQC,HMBC等2D NMR技术对一种新的配体1-(2-羧基苯基甲酰基)氨基硫脲(H3L)进行1H、13C NMR谱数据分析与归属,对于它与Cu+离子配位的化合物[Cu2(H3L)2Cl2](H2O)3也作了1H、13C NMR的测定,简单讨论了它的配位行为,粗略确定了它的结构.  相似文献   

10.
采用1H-1H COSY、NOESY、1H-13C HMQC及HMBC二维NMR技术鉴定了2个新合成的4β-5- 氟尿嘧啶取代-4′-去甲表鬼臼毒衍生物, 并对它们的1H和13C NMR 谱峰进行了全归属.  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

13.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

14.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

15.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

16.
17.
We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.  相似文献   

18.
Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.  相似文献   

19.
A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.  相似文献   

20.
Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.  相似文献   

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