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1.
蒙药呼和嘎日迪-9多糖的提取与含量测定   总被引:1,自引:0,他引:1  
采用热水提取-乙醇沉淀的方法从蒙药呼和嘎日迪-9中提取多糖,分光光度法测定糖含量,求得校准曲线的回归方程为y=0.00656x+0.324,相关系数为r=0.9994,平均回收率为101.2%,RSD=0.90%(n=5)。  相似文献   

2.
采用热水提取-乙醇沉淀的方法从蒙药兴格各其满都啦-21中提取多糖,用硫酸-苯酚法进行了糖含量的测定,求得其线性回归方程为y=0.00976x+0.451,相关系数为r=0.9996,平均回收率为99.2%,RSD=0.80%(n=5)。  相似文献   

3.
采用热水提取-乙醇沉淀法从苘麻子中提取多糖,Sevag法除蛋白,苘麻子多糖经大孔树脂分离、透析得两种多糖,即QMZP-1和QMZP-2,采用分光光度法(λ=486nm)测定两种多糖含量,分别为1.8%和0.75%,求得校准曲线的回归方程为y=0.00435x+0.561,相关系数为r=0.9998,平均回收率为100.1%,RSD=0.71%(n=5)。  相似文献   

4.
荞麦花多糖的提取及含量测定   总被引:3,自引:0,他引:3  
采用热水提取、乙醇沉淀的方法从荞麦花中提取出了水溶性多糖,采用硫酸-苯酚法在波长为497nm处进行了糖含量的测定,求得其校准曲线的回归方程为y=0.00508x 0.0294,相关系数为r=0.9978.平均回收率为99%-103%,RSD为0.74%.结果显示:荞麦花多糖的产率为2.5%.糖含量为41.63%.  相似文献   

5.
7种常见食用菌中多糖的提取和测定   总被引:1,自引:0,他引:1  
李承范 《光谱实验室》2012,29(2):996-999
采用热水提取、乙醇沉淀的方法从7种食用菌中提取出了水溶性多糖,采用蒽酮-硫酸法在波长620nm处进行了糖含量的测定,求得其校准曲线的回归方程为y=0.0094x+0.0057,相关系数r为0.9998。平均回收率为98.3%—102.7%,RSD为2.1%—3.2%。结果显示粗多糖的提取率为4.44%—16.75%,多糖含量为3.48%—6.91%。  相似文献   

6.
新疆野生樱桃李果肉中总黄酮含量的测定   总被引:1,自引:0,他引:1  
采用分光光度法测定樱桃李的总黄酮,以芦丁为对照品.NaNO2-AlCl3-NaOH体系为显色剂,确定了提取总黄酮的适当溶剂、提取时间等条件,建立了芦丁浓度-吸光度关系的回归方程:A=0.02571+10.3010C,r=0.9879.平均回收率为96.09%,RSD为0.533 %.方法简单、重现性好,是一个可行的方法.  相似文献   

7.
太行山黄芪中黄芪多糖的提取工艺   总被引:1,自引:0,他引:1  
采用碱性水提醇沉法进行黄芪多糖的提取,用蒽酮-浓硫酸比色法测定多糖的含量.通过改变黄芪的粒度,水浴比,水浴温度,提取次数,乙醇浓度及pH值等条件的研究,筛选出最佳提取工艺条件:于1:12的水浴比在70C水浴提取3次,乙醇浓度为90%,pH=10的条件下黄芪多糖的提取率最高,为19.2%.  相似文献   

8.
积雪草总黄酮提取工艺和含量测定研究   总被引:1,自引:0,他引:1  
确定积雪草总黄酮最佳提取工艺和含量测定方法,采用微波辅助法提取积雪草中的黄酮类化合物,通过正交实验确定了最佳提取工艺.分别以槲皮素和山奈酚为对照,采用紫外分光光度法在320nm处测定积雪草全草中的总黄酮.最佳工艺条件:提取次数3次,辐射时间20s,固液比1:10,功率480W.按最佳工艺条件提取总黄酮含量为8.40mg/g.回归方程为(槲皮素):y=29.993C+0.027,相关系数r2=0.9982,精密度和稳定性试验RSD分别为0.265%和0.172%(n≥6),平均加样回收率为99%,RSD=1.51%(n=5).回归方程为(山奈酚):y=36.928C+0.0178,相关系数rz=0.9991,精密度和稳定性试验的RSD分别为0.231%和0.190%(n≥6),平均加样回收率为99%,RSD=0.714%(n=5),样品的稳定性试验RSD为0.218%(60min).选择的最佳工艺对提取积雪草全草总黄酮确为最佳.用槲皮素或山奈酚标准品,采用紫外分光光度法,操作简便,结果准确,灵敏度高,重复性好,为积雪草全草中总黄酮含量测定的一种切实可行的方法.  相似文献   

9.
空心莲子草总黄酮的提取工艺   总被引:3,自引:0,他引:3  
确定空心莲子草总黄酮最佳提取工艺.采用微波辅助法提取空心莲子草中的黄酮类化合物,通过正交实验确定了最佳提取工艺.以芦丁为对照,采用紫外分光光度法在260nm处测定其中的总黄酮.最佳工艺条件:乙醇浓度40%,固液比1:20,微波辐射40s,微波功率320W,间歇提取2次.按最佳工艺条件提取总黄酮含量为30.012mg/g.回归方程为;y=33.21C+0.0106,相关系数r=0.9998,精密度试验RSD分别为1.1461(n≥6),平均加样回收率为99%,RSD=2.43%(n=6).样品的稳定性试验RSD为0.048%(120min).选择的最佳工艺对提取空心莲子草总黄酮确为最佳.用芦丁标准品,采用紫外分光光度法,操作简便,结果准确,灵敏度高,重复性好,为空心莲子草中总黄酮含量测定的一种切实可行的方法.  相似文献   

10.
白簕叶总皂苷提取工艺和含量测定研究   总被引:2,自引:0,他引:2  
采用微波辅助法提取白簕叶中的皂苷类化合物,通过正交实验确定了最佳提取工艺。以齐墩果酸为对照,采用紫外分光光度法在500nm处测定白簕叶中的总皂苷。最佳工艺条件:乙醇浓度70%,微波辐射30s,微波功率160W,固液比1∶10,间歇提取2次。按最佳工艺条件提取总皂苷含量为84.36mg/g。回归方程为:y=1.0167C+0.0006,相关系数r=0.9998,精密度和稳定性试验RSD分别为0.033%和0.034%(n≥6),平均加标回收率为99%,RSD=1.76%(n=6)。用齐墩果酸标准品,采用紫外分光光度法,操作简便,结果准确,灵敏度高,重复性好,为白簕叶中总皂苷含量测定的一种切实可行的方法。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.  相似文献   

18.
A novel method based on fiber gratings for measuring the effective indices of fiber modes is proposed. The effective index difference between the core mode and a cladding mode was obtained by analyzing the interference fringe of a pair of cascaded long-period fiber gratings. In order to extract the core mode index from the measured index difference, an index matching oil immersion method is proposed. By analyzing the interaction between the cladding mode and the oil applied on the cladding surface, the mode order and the effective index of the involved cladding mode might be calculated. Experimental results about the interference fringe shifts induced by the oil index and the oil-applied length are also presented.  相似文献   

19.
Optical Pulse Compression Schemes That Use Nonlinear Bragg Gratings   总被引:2,自引:0,他引:2  
Nonlinear optical pulse compression of picosecond pulses typically requires long lengths of optical fiber and multiple components. Periodic structures, such as fiber Bragg gratings, are highly dispersive at wavelengths outside of the photonic bandgap. This implies that such gratings can be used as very short all-fiber compressors. In this paper a number of such compression schemes are reviewed involving uniform and nonuniform fiber Bragg gratings, relying on both soliton and nonsoliton compression principles. Experimental results supporting the corresponding underlying theory are also presented. Finally, an extension of one of the compression schemes is shown, which allows the generation of adjustable high-repetition rate soliton trains.  相似文献   

20.
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