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1.
近红外光谱法快速分析葛根中的有效成分   总被引:23,自引:2,他引:21  
本文应用近红外光谱技术建立了快速检测葛根中有效成分的方法。研究了优化分析葛根总异黄酮、葛根素和大豆苷含量数学模型的各种条件,包括建模样品集的选择、化学值的定标、测量的方法及条件等,结果表明:建模样品集的化学值(又称真值)与近红外预测值的相关系数分别为:葛根总异黄酮r=0.975,葛根素r=0.984,大豆苷r=0.966;检验样品集的化学值与近红外预测值的相关系数分别为:0.982,0.975和0.981。说明所建模型具有实际应用价值。  相似文献   

2.
采用火焰原子吸收光谱法测定了葛根中金属元素钙、镁、铁、锰、锌的含量,采用醇提法提取葛根中总黄酮并用紫外分光光度法测定总黄酮含量。测定结果显示,葛根中含有丰富的总黄酮和金属元素,其中总黄酮含量为3.1718m g/g,金属元素含量为钙〉镁〉铁〉锌〉锰。实验结果为探讨葛根中总黄酮、金属元素与治疗呼吸系统疾病药理间的关系提供了有用的数据。  相似文献   

3.
野生葛不同部位铜、锌、铁、钙、镁含量测定   总被引:15,自引:5,他引:10  
用硝酸、高氯酸混合酸消解样品,采用原子吸收光谱法,测定了河南大别山区野生葛不同部位即葛根、葛藤、葛叶及花蕾中铜、锌、铁、钙、镁的含量,并对其结果进行了分析。结果显示:葛根、葛藤、葛叶及葛花中含有丰富的宏量元素钙、镁和有益的微量元素铜、锌、铁。铜的分布量依次为:叶〉花蕾〉葛藤〉葛根;锌的分布量依次为:叶〉花蕾〉葛藤〉葛根;铁的分布量依次为:葛根〉葛藤〉叶〉花蕾;钙的分布量依次为:叶〉葛根〉花蕾〉葛藤;镁的分布量依次为花蕾〉葛根〉叶〉葛藤。测定结果为探讨中草药中宏量、微量元素与治疗心脑血管疾病功效的关系提供了有用的数据;测定结果还显示:葛叶中铜、锌、钙含量居其他部位含量之首,适宜大力开发葛叶产品。  相似文献   

4.
刘梯楼  简红霞 《光谱实验室》2012,29(4):2468-2472
采用HNO3-HCIO4消解体系,应用火焰原子吸收光谱法(FAAS)和氢化物发生-原子荧光光谱法(HG-AFS)测定了洞口县野生葛根中Zn、Fe、Cu、Mn等15种微量元素的含量,方法对试样中各元素测定的相对标准偏差(RSD)为1.07%—4.29%,加标回收率为90.00%—104.00%,方法快速、准确、灵敏度高,适用于葛根中微量元素含量的测定。同时考察了微波提取、超声提取和传统煎煮法对野生葛根中15种微量元素的溶出情况。结果表明:野生葛根溶出液中含量较多元素的顺序为:Zn>Cu>Mn>Se>Fe,其余元素的含量均很少;野生葛根中Zn、Cu、Mn和Se的水溶性强,其溶出率比Fe高很多。  相似文献   

5.
新资源食品中微量元素测定方法的研究   总被引:8,自引:2,他引:6  
用硝酸-高氯酸消解样品,用火焰原子吸收光谱法测定新资源食品葛根、葛花、四叶参、仙人掌、菊花、小麦胚和蚕蛹中Cu,Zn和Fe元素的含量,并对其结果进行了分析。结果显示: 在选定的实验条件下,测定方法的回收率为94.66%~105.24%,测定Cu,Zn和Fe的精密度RSD分别为1.79%,0.71%和4.78%。建立的原子吸收光谱法简便、快速、灵敏、准确。经F检验与SNK检验,河南省新资源食品葛根、葛花、四叶参、仙人掌、菊花、小麦胚和蚕蛹中微量元素Cu,Zn和Fe含量分别为: 铜的分布量依次为: 菊花≈蚕蛹>葛花≈小麦胚≈四叶参≈葛根>仙人掌,锌的分布量依次为: 仙人掌>蚕蛹≈葛花≈葛根≈小麦胚≈四叶参≈菊花;铁的分布量依次为: 蚕蛹≈菊花≈葛根>葛花≈小麦胚≈四叶参≈仙人掌。  相似文献   

6.
不同产地葛根红外光谱的三级鉴定   总被引:4,自引:0,他引:4  
运用红外光谱法和二维相关光谱技术对天津八仙山、湖南壶瓶山、重庆金佛山三种产地的葛根样本进行了分析鉴定。分析结果表明:不同产地葛根的红外光谱(一级鉴定)和二阶导数谱(二级鉴定)具有一定的相似度,与淀粉和葛根素的谱图比对,三个样本都富含淀粉和一定量的葛根素,不同的是天津葛根在1 048 cm-1波数处的最强峰与淀粉在986 cm-1处的最强峰相差了62个波数,说明淀粉的含量较低,而在891,835和797 cm-1的特征峰与葛根素的指纹特征更一致,可见葛根素的含量要高一些。在二维相关谱图(三级鉴定)上,三种产地的葛根形成的峰簇的位置和数量不同,可以进行产地的鉴别。结果表明,对于不同产地葛根的分析,红外光谱法的三级鉴定是一种有效和快速的检测方法。  相似文献   

7.
治疗呼吸系统疾病中草药微量元素含量测定   总被引:2,自引:0,他引:2  
微量元素与人体健康有密切的关系,各微量元素之间按一定比例存在,以维护各自的生理功能,如果比例平衡失调,疾病就可能发生或发展,中草药中含微量元素丰实。选取了16种临床上常用的治疗呼吸系统疾病的中草药百合、鱼腥草、甘草、板兰根、五味子、黄芩、贝母、何首乌、紫草、石菖蒲、半夏、银杏、金银花、葛根、柴胡和川芎,采用HNO3-HClO4湿法消化,用原子吸收分光光度计测定其Fe,Ni,Mn,Cr,Cu和Zn六种微量元素的含量,通过药物中微量元素含量的测定,观察不同药物中微量元素的含量差别。测定结果显示,16种中草药中微量元素含量丰富,含量较多的微量元素有Fe,Zn和Mn,不同药物中含量有所差别,含微量元素较丰富的是何首乌、银杏叶、柴胡、五味子、半夏和紫草;含量较少的葛根、石菖蒲和板兰根。分析结果为研究中药理论、药理药效等方面的深入研究提供了有效的参考数据。  相似文献   

8.
中药是复杂的化学体系,建立快速、有效的分析方法有助于中药水煎液的实时质量控制。葛根在处方中常用有三种,分别为粉葛、野葛和煨葛(葛根炮制品),且传统应用中多采用水煎煮的方式,因此,采用傅里叶变换红外光谱技术(FTIR),二阶导数光谱(SD-IR),结合二维相关红外光谱(2D-IR)对三种葛根水煎液进行快速分析。结果表明,通过FTIR和SD-IR光谱能够将粉葛水煎液明显区别于野葛和煨葛水煎液。经过2D-IR分析,发现野葛经过煨制后水煎液化学成分发生了变化,二者在主要的自动峰和交叉峰的位置和强度方面存在较大差异,在1 800~1 300 cm-1范围内,野葛水煎液中最强的自动峰为1 556 cm-1,次强峰为1 561 cm-1,而在煨葛水煎液中最强自动峰为1 563 cm-1,次强为1 572 cm-1,再次为1 556 cm-1。另外,在野葛水煎液中出现了明显的1 536和1 634 cm-1自动峰,二者的强度相当。野葛及煨葛水煎液的2D-IR光谱中,出现的自动峰1 448和1 518 cm-1的相对强度有较大的差异。在野葛水煎液的2D-IR光谱中,交叉峰(1 518,1 561)和(1 518,1 563) cm-1强于煨葛水煎液中相应峰。凭借2D-IR自动峰和交叉峰可以较直观地鉴别野葛和煨葛水煎液,并揭示二者相应各官能团的变化规律,能够为葛根在临床处方应用过程中,水煎液的快速质量控制提供依据。利用FTIR,SD-IR结合2D-IR的整体性和宏观指纹性,可以为中药等复杂体系的逐级鉴别提供快速、准确的方法和手段。  相似文献   

9.
李爱红 《光谱实验室》2012,29(4):2407-2409
采用火焰原子吸收光谱法测定了半边莲、半枝莲、山豆根、苦参和葛根5种抗肝癌中草药中Zn、Cu、Mn、Fe和Mg的含量。结果表明,各元素在所选的中草药中含量丰富。5种中草药中,半枝莲的Zn和Mn含量最高,半边莲的Cu和Fe含量最高,山豆根中Zn/Cu比值最高,而Mg的含量则均很高。该结果可为研究中草药的抗肝癌作用机理提供一定的信息。  相似文献   

10.
瑶药野葛花中6种无机元素的测定   总被引:2,自引:0,他引:2  
用原子吸收光谱法测定野葛花原生药、野葛花汤剂中的 Ca、Mg、Cu、Zn、Fe、Mn等 6种无机元素含量。结果表明 ,原药和水煎液中 Ca、Mg含量比较丰富 ;各种元素的煎出率存在着较大的差异 ,其中 Cu、Zn、Fe的煎出率较高 ,Zn最高 ,达到了 82 .5 6 % ;Ca最低 ,为 5 .5 8%。并且将其结果与葛根的无机元素做了比较。为探讨无机元素与中药药效之间的关系提供了基础数据。  相似文献   

11.
The nonlinear dynamics of a waveguide CO2 laser with combined periodic loss and pumping modulation is investigated theoretically and experimentally. The possibilities of controlling time and energy parameters of the output radiation using the corresponding selection of the detuning of the cavity's longitudinal mode from the center of the amplification line, the amplitude, and the frequency of loss modulation are demonstrated. The observed asymmetric dependence of the lasing-radiation density on the detuning of the cavity frequency is explained by the attendant modulation of the refractive index of the loss modulator. To whom correspondence should be addressed. B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 471–478, July–August, 1999.  相似文献   

12.
We describe a modified GELIOS System intended to automate the atomic-absorption spectrometers AAS, S115, SATURN, and Perkin-Elmer 503. Software is prepared in the visual environment of programming DELFI-3 and functions under the control of Windows 95. A distinguishing feature of the GELIOS System is simultaneous search for the peak and area of the absorption signal, correction of the errors of measurements, automatic digital filtration of data, control of the time of operation of hollow-cathode lamps, measurement of spectra and the statistical resource of the service life of hollow-cathode lamps, use of different methods to construct a calibrating graph, the possibility of memorizing the data of the analysis in an archived file, and a formation of the report for printing. The system contains an electrovic data directory on atomicabsorption analysis in five volumes for 67 elements of the Mendeleev system. To whom correspondence should be addressed. “University” Science and Production Center, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 734–737, September–October, 1999.  相似文献   

13.
基于高光谱技术的酸奶中常见致病菌的快速鉴别及计数   总被引:1,自引:0,他引:1  
酸奶是一种发酵型乳制品饮料,因其特殊的功能性和良好的口感而广受欢迎。但由于商业链的不正当运行,如奶源非法获取、灭菌不充分等原因,导致酸奶中致病菌大量滋生,酸奶中毒事件频繁发生。酸奶中常见的致病菌主要有大肠杆菌、金黄色葡萄球菌和沙门氏菌,这三种致病菌由人体摄入并达到一定的数量时会产生腹痛、腹泻等严重的消化道疾病,并且会破坏人体肠道内的正常菌群平衡,因此国标对奶制品中这三种致病菌的数量已有明确的限量规定。由于酸奶的主要消费对象为老人和小孩,故其潜在危害不容小觑。传统菌落检测方法虽具有简单,灵敏、可操作性强等优点,但当不同菌落混杂在一起时无法同时进行定性定量的检测,且具有试剂成本高,检测周期长,人为因素影响较大等缺点。因此开发一种快速、简单、准确的混合鉴定计数方法为避免致病菌对酸奶的潜在危害提供了有效的途径。高光谱技术同时包含样本的光谱信息与图像信息,既能够根据化学组分的微小变化进行精确识别(光谱信息),又能够反映出菌株在外部多层次的变化(图像信息)。因此该研究尝试对比高光谱图像技术和光谱技术,采用模式识别的方法,对比不同的模型识别结果,优选出最佳识别率的识别模型作为计数模型,最后通过最佳鉴别计数模型的识别分类结果来达到对酸奶中常见致病菌鉴定计数的目的。首先,购买酸奶中常见的乳酸菌种(保加利亚乳杆菌、嗜热链球菌、嗜酸乳杆菌、干酪乳杆菌、植物乳杆菌)和潜在污染的致病菌种(金黄色葡萄球菌、大肠杆菌、沙门氏菌)等标准菌株进行培养,提取经过48 h培养后的菌落图像信息和光谱信息。采用几种不同的预处理方式(SNV,MC,MSC,1stDER,2ndDER)对所提取的光谱数据进行预处理,并应用遗传算法筛除光谱数据中冗余的波段,保留有效波段。利用图像处理技术对图像信息中的菌株与培养基背景进行去除,然后采用主成分分析法从每幅图中优选出3个特征波长,并运用图像处理技术从特征波长所对应图像中提取菌株的18个基于GLCM的纹理特征信息。挑选合适的主成分分别建立不同的鉴别模型(LDA,KNN,BP-ANN,LS-SVM),通过其最终的鉴别模型的识别率来确定最佳鉴别计数模型。最后从标准菌株中分别挑选出30株进行计数测试,通过比较模式识别的分类数量结果与菌株的实际数量来验证模式识别效果的准确率。研究表明,运用SNV预处理后光谱数据在提高信噪比效果上明显优于其他几种预处理方式。745.790 8,773.098 4和779.207 0 nm为图像信息中方差贡献率最大的三个波长,运用从特征波长所对应的图像中所提取的纹理特征信息建立图像识别模型。通过对比图像信息和光谱信息的模式识别结果发现,光谱特征鉴别模型普遍优于图像纹理特征鉴别模型,且当主成分数为9时,运用光谱特征所建立的LS-SVM模型的校正集识别率为96.25%,预测集的识别率为91.88%,为最优模型。采用优选的最优模型对菌株进行识别计数,大肠杆菌计数的相对误差为3.33%,金黄色葡萄球菌和沙门氏菌计数的相对误差均为0,验证了高光谱技术应用于酸奶中常见致病菌的鉴别计数的可行性。  相似文献   

14.
A number of phenomena that determine the nature of the fluorescence of free complex molecules and the possibility of its analytical application are considered. Attention is specially paid to the specific features of the energetics of radiationless transitions, the role of statistical factors in the formation of spectral properties and the interrelationship among the luminescence-spectrum characteristics of rarefied vapors of complicated molecules, and the processes of energy transfer in collisions. The properties of polarized fluorescence of hot and jet-cooled vapors, the processes of relaxation of anisotropy in time and during collision reorientation, and transfer of anisotropy in photodisintegration are analyzed. Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 620–634, September–October, 1998.  相似文献   

15.
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   

16.
Quantum-chemical calculations of the excited electronic states of a porphyrin dication have been performed by the CNDO/S method for different angles determining the saddle-like and ruffled distortions of the porphyrin macroring. It is shown that saddle-like distortions arising as a result of a tilt of the pyrrole rings have a significant influence on the energies of the molecular orbitals and energies of the excited electronic states of porphyrin molecules, especially on the oscillator strength of the G→Q transition. The results of the calculations performed are in good agreement with the experimental spectra of porphyrin dications. To whom correspondence should be addressed. Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998. Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 559–562, July–August, 1999.  相似文献   

17.
Sea ice contains flaws including frictional contacts. We aim to describe quantitatively the mechanics of those contacts, providing local physics for geophysical models. With a focus on the internal friction of ice, we review standard micro-mechanical models of friction. The solid's deformation under normal load may be ductile or elastic. The shear failure of the contact may be by ductile flow, brittle fracture, or melting and hydrodynamic lubrication. Combinations of these give a total of six rheological models. When the material under study is ice, several of the rheological parameters in the standard models are not constant, but depend on the temperature of the bulk, on the normal stress under which samples are pressed together, or on the sliding velocity and acceleration. This has the effect of making the shear stress required for sliding dependent on sliding velocity, acceleration, and temperature. In some cases, it also perturbs the exponent in the normal-stress dependence of that shear stress away from the value that applies to most materials.

We unify the models by a principle of maximum displacement for normal deformation, and of minimum stress for shear failure, reducing the controversy over the mechanism of internal friction in ice to the choice of values of four parameters in a single model. The four parameters represent, for a typical asperity contact, the sliding distance required to expel melt-water, the sliding distance required to break contact, the normal strain in the asperity, and the thickness of any ductile shear zone.  相似文献   

18.
采取标准锌显色剂与锌发生显色反应,生成不溶于水的絮状络合物。用光谱仪测它的吸光度,研究其特征谱与吸光度的特点,建立其浓度与特征波长吸光度间的数学模型。本文所采用的显色剂主要与锌、铜、镉、镍四种离子发生络合反应。因此分别探索了四种离子高浓度以及低浓度时显色反应的吸光度,最终通过得到锌离子浓度与吸光度的关系式以及锌离子浓度与四波长下四种离子混合溶液显色后的吸光度的关系式,给出了锌离子的吸光度与总吸光度的关系式。显色反应能否满足分光光度法的要求,主要与显色剂的性质有关,同时显色反应的条件也至关重要。因为在显色反应过程中,主要是锌离子与锌显色剂发生络合反应形成络离子,进而形成絮状络合物。络离子一般比较稳定,但在水溶液中也存在着电离平衡,也就是说当显色条件发生变化时,既有可能形成络离子,也有可能发生络离子的分解,从而影响络合反应的程度。显色条件包括显色剂用量、pH值、反应温度、显色时间、待测溶液的盐度以及浊度等。重点研究待测溶液的盐度对锌离子浓度测量值的影响,并通过实验给出影响规律以及校正模型。  相似文献   

19.
This review is devoted to the analysis of the problems related to fabrication of the Si porous layers. The review was motivated by a great interest to Si-based porous materials from nano- to macro-scale for various applications in electronics, optoelectronics, photonics, chemical sensors, biosensors, etc. The peculiarities of the silicon porosification and the principles of preparing porous layers are considered in the present article. Various methods used for Si porosification such as chemical stain etching, chemical vapor etching, laser-induced etching, metal-assisted etching, spark processing and reactive ion (plasma) etching were analyzed. However, the main attention was focused on electrochemical porosification of Si. The review discusses in detail the influence of parameters such as electrolyte composition and pH, current density, etching time, temperature, wafer doping and orientation, lighting, magnetic field, and ultrasonic agitation on the process of Si porosification. It was shown that the structure of porous silicon strongly depends on both technological parameters of electrochemical etching and the parameters of the semiconductor subject to treatment. This review also addresses the main properties of porous silicon, porous multilayer and 3D structure formation, oxidation of porous Si, release of the porous layer, drying, storage, etching, filling and surface functionalizing of porous Si. Features of III-V compound porosification are also briefly analyzed.  相似文献   

20.
赵银英 《光谱实验室》2009,26(2):235-238
利用ICP-AES分析技术,通过对样品处理、元素分析谱线、酸度等因素进行试验研究,综合确定了分析条件,对铜电解液中杂质元素(Fe、Ni、Pb、Bi、Sb、Zn、As)进行了ICP-AES测定。结果表明,ICP-AES测定铜电解液中Fe、Ni、Pb、Bi、Sb、Zn和As,可以满足铜电解生产的需要,为高纯阴极铜的生产起了指导作用。  相似文献   

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