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1.
应用NMR技术,对一种新结构的二聚异喹啉生物碱进行了结构分析测定,其中包括^1HNMR,^13CNMR,和二维谱C-H CosY,H-H CosY。  相似文献   

2.
利用1H-1HCOSY,13C-1HCOSY,13C-1H远程COSY以及选择性远程DEPT13CNMR谱,对2,4-二硝基五环[4.3.0.02,5.03,8.04,7]壬烷的1H和13CNMR谱进行了完全的归属.  相似文献   

3.
从生药路路通分离得到2个齐墩果烷骨架的五环三萜类化合物.通过13CNMR,DEPT,1HNMR,2D1H-13CCOSY,2D1H-1HCOSY,IR,MS和元素分析阐明了它们的结构.(1)为2α,3β-二羟基-23-去甲-齐墩果-4(24),12(13)-二烯-28-羧酸,(2)为2α,3β,23-三羟基齐墩果-12(13)-烯-28-羧酸,(1)未见文献报道,(2)是首次从这一植物中分离得到  相似文献   

4.
利用^1H-^1HCOSY,^13C-^1HCOSY,^13C-^1H远程COSY以及选择性远程DEPT^13CNMR谱,对2,4-二硝基五环[4.3.0.0^2.5,0^3.8.0^4,7]壬烷的^1H和^13NMR谱进行了完全的归属。  相似文献   

5.
从生药路路通分离得到2个齐墩果烷骨架的五环三萜类化合物。通过^13C NMR,DEPT,^1H NMR,2D^1H-^13C COSY,2D^1H-^1H COSY,IR,MS和元素分析阐明了它们的结构。(1)为2α,3β-二羟基-23-去甲-齐墩果-4(24),12(13)-二烯-28-羧酸,(2)为2α,3β,23-三羟基齐墩果-12(13)-烯-28-羧酸,(1)未见献报道,(2)是首次从  相似文献   

6.
NEWENERGY-SAVINGCEMENT-IRON-RICHFLUORALUMINATECEMENTHuang;WenxiChengduDesign&ResearchInstituteofBuildingMaterialsIndustryQian...  相似文献   

7.
本文通过对5对meso和dl-2,3-二氰基-2,3-二(p-X-取代苯基)丁二酯二乙醋的(X=OCH3、CH3、H、Cl、NO2)研究发现,meso—异构体的γC=0都高于相应dl-异构体的γC=0而meso异构体的γC-O-C却比相应dl-异构体的低,立体异构体直观地在红外光谱上反映出规律性变化。  相似文献   

8.
用乙酸、硫氰化铵与氨基酸反应,得到4个2-硫代乙内酰脲配体S=CNHC(O)CH(R)N↓H,它们分别与Co2(CO)8反应,合成出两类4个三核钴羰基硫簇合衍生物:Co3(CO)7(μ3-S)〔μ-η2-SC=NC(O)CH(R)N↓H(Ia,Ib)和Co3(CO)6(μ3-S)(μ-η2-SC=NC(O)CH(R)N↓H)(:CNHC(O)CH(R)N↓H)(Ⅱc,Ⅱd).对4个族合物进行了元素分析、IR谱、1HNMR和MS表征,并推测出它们的分子结构.  相似文献   

9.
八氯二丙醚的合成和二维核磁谱研究   总被引:2,自引:0,他引:2  
八氯二丙醚由三氯乙烯和氯甲醚或甲醛制备。产物的结构由^1HNMR,^13CNMR,DEPT谱、二维核磁^13C-^1H相关谱,COSY谱、质谱、红外谱和元素分析确定。  相似文献   

10.
THEOPTICALOBSERVATIONOFTHECOLLISTIONSOFCOMETSHOEMAKER-LEVY9WITHJUPITER¥ZhouHongnan(DepartmentofAstronomy,NanjingUniversity,21...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

15.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

16.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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