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1.
用连苯三酚合成2,3,4-三羟基苯乙酮,用苯甲酸乙酯、对羟基苯甲酸甲酯与水合肼反应,合成苯甲酰肼和对羟基苯甲酰肼,然后用2,3,4-三羟基苯乙酮与苯甲酰肼、对羟基苯甲酰肼、苯肼反应,合成了三种新的2,3,4-三羟基苯乙酮腙类试剂。研究了腙类试剂的红外光谱、紫外光谱、荧光光谱特性。  相似文献   

2.
用苯胺与水杨醛反应合成了4-苯偶氮水杨醛,用苯甲酸乙酯、对羟基苯甲酸甲酯与水合肼反应,合成了苯甲酰肼、对羟基苯甲酰肼,然后用4-苯偶氮水杨醛与苯甲酰肼、对羟基苯甲酰肼、苯肼、异烟肼反应,合成了四种新的4-苯偶氮水杨醛腙类试剂。研究了这四种腙类试剂的红外光谱、紫外光谱、荧光光谱特性。  相似文献   

3.
药物共晶可以改善药物活性成分的物理化学性质,这一特性使其在改善药物性质特征方面具体很大的应用潜力。我们小组用拉曼光谱(Raman spectroscopy)技术对吡嗪酰胺(Pyrazinamide,PZA)、2.5-双羟基苯甲酸(2.5-dihydroxybenzoic acid,2.5-DHBA)及其研磨和溶剂共晶体进行表征分析。该光谱显示了拉曼光谱可以有效鉴别吡嗪酰胺、2.5-双羟基苯甲酸及其共晶体。运用密度泛函理论(Density functional theory,DFT)对吡嗪酰胺和2.5-双羟基苯甲酸的两种可能结构进行结构优化和光谱模拟。结果显示理论形式A与实验结果很好的拟合。推断共晶体氢键的形成位置为2.5-双羟基苯甲酸中羧基O16和吡嗪酰胺上H10,该处形成第一处氢键,而2.5-双羟基苯甲酸中羧基H15和吡嗪酰胺上O11形成第二处氢键。  相似文献   

4.
以电化学方法合成了N-对苯甲氧基-对-乙氧基-苯甲硫酰胺合铜(I)配合物,测定了该化合物的红外光谱和核磁共振谱(^1H、^13C)。结果表明:该化合物主要以硫酸铜形式与铜(I)配位。  相似文献   

5.
采用两种光致变色俘精酸酐体系化合物[1,2,4-三甲基-5-苯基-3-吡咯甲叉(异丙叉)俘精酸酐和对-N,N-二甲基苯基-2-甲基-3-恶唑甲叉(异丙叉)俘精酸酐]制备了单层双色聚甲基丙烯酸甲酯(PMMA)复合薄膜感光记录材料。采用双波长(650nm和488nm)图像存储和读出光路,实现了用两种波长在双色复合薄膜的同一位置同时记录两幅图像。当分别用各自对应的波长读出时,两幅图像各自获得了高衬比度,且二者之间的串扰很小,证明了在双色光致变色俘精酸酐材料上进行双波长复用图像光存储的可行性。  相似文献   

6.
猪去氧胆酸衍生物的NMR研究   总被引:1,自引:0,他引:1  
对6α-羟基-3α-苯甲酰氧基-5β-胆烷酸甲酯(化合物1)及3α-羟基-6α-苯甲酰氧基-5β-胆烷酸甲酯(化合物[STHZ]2[STBZ])进行了1H,13C NMR检测,通过DEPT及DQF-COSY,13C-1H COSY, COLOC等NMR技术对其1H和13C NMR数据进行了全归属和详细的解析,并指出了其NMR数据特征.  相似文献   

7.
肖孝梅  徐石海  杨凯 《光谱实验室》2005,22(6):1138-1141
从采自西沙永兴岛的西沙仙掌藻Halimeda Xishaensis样品中分离鉴定了4个单羟基甾醇,5-烯-3α-胆甾醇(1),5-烯-3β-麦角甾醇(2),豆甾醇(3),β-谷甾醇(4)和4个单体化合物,1-正二十三碳酸甘油酯(5),豆甾-4-烯-3β,6β-二醇(6),N-(1-羟甲基-2-羟基-3E-十五碳烯)-正二十七酰胺(7)和1个丁四醇(8)。  相似文献   

8.
雍建平  赵巍 《光谱实验室》2011,28(5):2241-2244
以18β-甘草次酸和4-氨基苯酚为原料,在N,N'-二环己基碳二酰亚胺(DCC),1-羟基苯并三唑(HOBt)/4-N,N-甲基吡啶(DMAP),N-甲基吗啉(NMM)作用下合成了N-(4-羟基-苯基)-甘草次酸酰胺,通过DCC、DCC/HOBt催化有机酸形成酯、酰胺反应的历程解释了在DCC/HOBt催化体系中目标化合...  相似文献   

9.
报道了从苦皮藤叶中得到的两个新倍半萜醇酯化合物.利用NMR和2D NMR技术测得它们的化学结构分别为1β-苯乙烯酰氧基,9β-(2-羟基)-异丁酰氧基,2β,6α,8α,15-四乙酰氧基-4α-羟基-β-二氢沉香呋喃和1β-苯甲酰氧基,9β-(2-羟基)-异丁酰氧基,2β,6α,8α,  相似文献   

10.
在表面活性剂十二烷基磺酸钠存在下,于pH3.6的乙酸-乙酸钠缓冲溶液中,铁(Ⅲ)与3-氯-N-羟基-2,2-二甲基丙酰胺形成稳定的络合物,在490nm处有最大吸收,3-氯-N-羟基-2,2-二甲基丙酰胺浓度为2-160mg·L<'-1>范围内符合朗伯-比耳定律,ε<,490>=1.05×10<'4>L·mol<'-1>...  相似文献   

11.
本文研究了三种反对称Schiff碱的Raman振动特性,分析了三种Schiff碱的拉曼振动模式,给出了所观察到的Raman振动的归属。  相似文献   

12.
5-(R)-(l-孟氧基)-2(5H)-呋喃酮(A)与苯甲醛肟(B)进行1,3-偶极环加成反应时得到两个产物, 我们应用NOE及HMBC技术确证了它们的结构. 由于反应物(A)的绝对构型已经X-射线单晶衍射法确证, 因此通过NMR研究产物呋喃酮环上各手性碳的关系, 最终确立产物的绝对构型.  相似文献   

13.
For the homologous series p-alkoxybenzal-p′-ethoxyaniline the nematic-isotropic transition temperature TNI, NMR inter-pair dipolar interaction, and for the first time the frequency dependent dielectric response concerning the even-odd effect at microwave frequencies were measured. For TNI a pronounced even-odd effect of type I was found. Some pecularities were observed in the NMR data of the molecules C5 and C7, i.e. with 5 and 7 carbon atoms in the benzal end chain. An even-odd effect was found in the dielectric response at microwave frequencies. However, at 23.5 GHz the molecules C5 and C7 show a significant deviation from the even-odd behaviour in the series, which is not evident at the lower microwave frequency of 7.8 GHz. To explain these deviations from the even-odd effect it is assumed that for C5 and C7 a modification of the chain configuration takes place in the nematic phase.  相似文献   

14.
A time domain finite volume method(TDFVM)based on wave theory is developed to analyze the transient response and natural characteristics of structural-acoustic coupling problems in an enclosed cavity.In the present method,the elastic dynamic equations and acoustic equation in heterogeneous medium are solved in solid domains and fluid domains respectively.The structural-acoustic coupling is implemented according to the continuity condition of the particle velocity along the normal direction and the normal traction equilibrium condition on the interface.Several numerical examples are presented to validate the effectiveness and accuracy of the present TDFVM.Then the effects of water depth on the acoustic and vibration characteristics and the natural characteristics of a structural-acoustic coupling system are analyzed.The numerical results show that the increase of water depth leads to a stronger coupling between the water and structure and the decrease of natural frequencies of coupling system,The computational cost and memory of this method are small and it can be applicable to structural-acoustic coupling problems in the heterogeneous fluid.  相似文献   

15.
We will present in this work the quantitative analysis of the relationship between the doping concentrations of GeO 2 and B 2 O 3 in the core and cladding regions and the temperature sensitivity of the resonance wavelength shift in long-period fiber gratings (LPFGs). Based on this analysis, the temperature sensitivity was suppressed and enhanced to 0.002 nm/°C and 0.28 nm/°C, respectively. We will also discuss the effect of the residual mechanical stress on the optical and mechanical properties of LPFGs. In particular, we will present the measurement results of the dependence of the refractive index change and mechanical strength on the residual mechanical stress in the boron-doped fibers with depressed clad and matched clad.  相似文献   

16.
A new technique of Mueller-matrix mapping of the birefringent structure of biological preparations of human organs tissues is suggested. The algorithms of reconstruction of average values and magnitude of fluctuations of the phase (birefringence) and amplitude (dichroism) of optically anisotropic structure of myocardium and connective tissue component of the vaginal wall histological section are proposed. The magnitudes and ranges of changes in the statistical moments of the 1st-4th order that characterize the distribution of average values and magnitude of fluctuations of birefringence and dichroism of the myocardium and connective tissue of the vaginal tissues histological sections were determined. Joint studies of distributions of the characteristics of phase and amplitude of the anisotropy of myocardium and connective tissue component of the vaginal wall tissues of different states were performed. The cases of various necrotic changes in the myocardium and pathological conditions of the vagina wall (prolapse of the genitals) are examined. Balanced accuracy of the method of Mueller-matrix polarization-phase and diffuse tomography of optically anisotropic polycrystalline networks in the differentiation of necrotic and pathological changes in human organs is determined.  相似文献   

17.
不同比例有机无机肥配施土壤腐殖质组分的光谱学特征   总被引:3,自引:0,他引:3  
以16年长期定位试验为基础,探讨不同比例有机无机肥配施对土壤腐殖质特征的影响.通过分离纯化腐殖质中的胡敏酸(H A)和富里酸(FA)组分,并利用元素分析、红外光谱和核磁共振研究分析了F1(70% 化肥+30% 有机肥)、F2(50% 有机肥+50% 化肥)和F3(100% 有机肥)三种施肥方式下的HA和FA含量及结构变...  相似文献   

18.
In the present study, experiments of membraneless alkaline sono-electrolysis are combined to a mathematical model describing the performance of a sono-electrolyzer based on the electrochemical resistances and overpotentials (activation, Ohmic and concentration) and the oscillation of the acoustic cavitation bubble, and its related sono-physical and sonochemical effects, as a single unit and within population. The study aims to elucidate the mechanism of action of acoustic cavitation when coupled to alkaline electrolysis, using a membraneless H-cell configuration and indirect continuous sonication (40 kHz, 60 We). The calorimetric characterization constituted the bridge between experimental results and the numerical and simulation approach, while the quantification of the rate of produced hydrogen both experimentally and numerically highlighted the absence of the contribution of sonochemistry, and explained the role of ultrasounds by the action of shockwaves and microjets. Finally, the energetic sono-physical approach allowed an estimation of the predominance of the shockwaves and microjets effects according to the bubble size distribution within the population corresponding to the acoustic conditions of the study. The resulting macroscopic effect in sono-electrolysis process has been assessed considering the induced degassing. A reduction in the fraction of electrodes’ coverage by bubbles from 76% to 42% has been recorded, corresponding to a decrease of 7.2% in Ohmic resistance and 62.35% in bubble resistance.  相似文献   

19.
Combination of several drugs is often necessary especially during long-term therapy. The competitive binding drugs can cause a decrease in the amount of drug bound to protein and increase the biological active fraction of the drug. The aim of this study is to analyze the interactions of Lomefloxacin (LMF) and Colchicine (COL) with human serum albumin (HSA) and to evaluate the mechanism of simultaneous binding of LMF and COL to protein. Fluorescence analysis was used to estimate the effect of drugs on the protein fluorescence and to define the binding and quenching properties of drugs-HSA complexes. The binding sites for LMF and COL were identified in tertiary structure of HSA with the use of spectrofluorescence analysis. The analysis of fluorescence quenching of HSA in the binary and ternary systems show that LMF does not affect the complex formed between COL and HSA. On the contrary, COL decreases the interaction between LMF and HSA. The results of synchronous fluorescence, resonance light scattering and circular dichroism spectra of binary and ternary systems show that binding of LMF and COL to HSA can induce micro-environmental and conformational changes in HSA. The simultaneous presence of LMF and COL in binding to HSA should be taken into account in the multi-drug therapy, and necessity of using a monitoring therapy owning to the possible increase of the uncontrolled toxic effects. Molecular modeling of the possible binding sites of LMF and COL in binary and ternary systems to HSA confirms the spectroscopic results.  相似文献   

20.
景德镇仿龙泉青瓷与龙泉青瓷组成特征研究   总被引:1,自引:0,他引:1  
龙泉青瓷不仅受到了国内外陶瓷爱好者的热捧,还被不同地区广大窑工争相效仿,其中以景德镇明清时期仿制最具代表性。利用能量色散X荧光光谱分析仪对38 件宋、元、明时期的龙泉青瓷以及明代景德镇仿龙泉青瓷进行了测试,并结合烧成温度分析结果,从时空角度对比分析了两地青瓷胎釉组成特征、演变规律和形成原因,有助于了解我国南方青釉瓷的演变发展、相互交流和影响,为不同产地青瓷的断源断代提供了一定的科学依据。  相似文献   

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