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研究了在TritonX-100存在下,在PH8.0的乙醇介质中,用5-Br-PADAP作为显色剂,应用分光光度法连续测定血清中的铜,锌。本法具有较高的灵敏度,Cu^2+-5-Br-PADAP的ε为8.50*10^4L.mol^-1.cm^-1,Zn^2+-5-Br-PADAP的ε为9.65*10^4L.mol^-1.cm^-1。铜线性范围为0-0.45mg.L^-1,锌线性范围为0-0.40mg. 相似文献
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研究了以2-(5-溴-2-噻唑偶氮)5-二乙氨基苯酚(5-Br-PADAP)作显色剂,CCD(Charge Coupled Device,电荷耦器件)二极管阵列检测分光光度装置采及收光谱,用偏最小二乘法解析,同时测定了粮食中铜和锌。方法的线性范围锌为0.05~0.40μg.ml^-1,铜为0.02~0.60μg.ml^-1;检出限铜为0.02μg.ml^-1,平均加标回收率锌为93.3%~95.7 相似文献
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珠江三角洲蔬菜中的锰 总被引:2,自引:0,他引:2
廖金凤 《广东微量元素科学》2000,7(5):56-58
珠江三角洲蔬菜中锰的含量范围为5.01*10^-6-346.8*10^-6,平均62.91*10^-6,大多数蔬菜中锰的含量为20*10^-6-70*10^-6,叶菜类锰的平均含量为69.20*10^-6,头菜类平均为19.85*10^-6,果蔬菜类,花菜类平均为38.90*10^-6。蔬菜中锰的含量与蔬菜种类和土壤性质有密切关系。 相似文献
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气相色谱法测定环境空气和废气中的2-丁酮和苯 总被引:1,自引:0,他引:1
用活性炭吸附环境空气和废气中的2-丁酮和苯,经二硫化碳解吸后用气相色谱法测定。方法的回收率2-丁酮为86.2%-104.6%, 为91.3%-105.7%。相对标准偏差2-丁酮为2.5%-2.8%,苯为2.5%-3.8%,当采样体积为20L,解吸液体积为2.00ml,进样体积为2μl时,2-丁酮和苯的最低检测浓度分别为0.03mg.m^-3和0.01mg.m^-3。 相似文献
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5-(对-羟基苯基):-5-苯基乙内酰脲的反相高效液相手性分离测定法 总被引:2,自引:0,他引:2
以β-CD为手性流动相添加剂、苯巴比妥为内标,于FLC-C8反相柱上建立了鼠肝微粒体中5-(对-羟基苯基)-5-苯基乙内酰脲(p-HPPH)外消旋体的拆分方法。测得p-HPPH对映体的线性范围为0.5~110mg/L(r=0.9996);最低检出量为5ng(S/N=3);S-p-HPPH的回收率为93.6%±2.8%,R-p-HPPH的回收率为94.7%±1.8%;日内和日间精密度RSD值均小于2%。所建立的方法具有结果准确、操作方便等特点。 相似文献
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示波极谱法连续测定食品中微量锌铁锰铜铅镉砷 总被引:3,自引:0,他引:3
研究了三乙醇胺-乙二胺-硫氰酸钾-乙酸-碘经钾-盐酸-酒石酸锑钾体系示波极谱法在同一份食品试样中连续测定七种微量元素。在该体系中,七种微量元素可分别产生稳定的极谱二阶导数波,空白无峰出现。锌、铁、锰、铜、铅检出限为0.0mg.kg^-1,砷、镉检出限为0.005mg.kg^-1。锌、铁、铜、铅0.01~0.80μg.ml^-1,镉0.005~0.80μg.ml^-1,锰0.01~0.50μg.ml 相似文献
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火焰原子吸收光谱法测定锰电解液中铜锌镉铅 总被引:5,自引:0,他引:5
在酸性和低温条件下,用适量乙醇使锰电解液中的MnSO4沉淀分离,用火焰原子吸收光谱法直接测定锰电解液中铜,锌、镉和铅含量。方法简便、快速,实用,具有较高的精密度和准确性。相对标准偏差3.8%-4.5%,回收率90.5%-106.5%,特征浓度铜为0.49μg.ml^-1/1%,锌为0.008μg.ml^-1/1%,镉为0.015μg.ml^-1/1%,铅为0.18μg.ml^-1/1%。 相似文献
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有机阴离子的人工接受体的合成 总被引:2,自引:0,他引:2
报道以D-天冬酰胺为起始原料经9步反应合成旋光活性的(2R,8R)-二羟甲基-1,5,9-三氮双环〔4.4.0〕癸-9-烯盐酸盐,总产率为25.4%. 相似文献
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Chi Zhang Zhe Liu Shaoming Lu Liujun Xiao Qianqian Xue Hongli Jin Jiapan Gan Xiaonong Li Yanfang Liu Xinmiao Liang 《Molecules (Basel, Switzerland)》2022,27(13)
Ginseng, which contains abundant ginsenosides, grows mainly in the Jilin, Liaoning, and Heilongjiang in China. It has been reported that the quality and traits of ginsengs from different origins were greatly different. To date, the accurate prediction of the origins of ginseng samples is still a challenge. Here, we integrated ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) with a support vector machine (SVM) for rapid discrimination and prediction of ginseng from the three main regions where it is cultivated in China. Firstly, we develop a stable and reliable UHPLC-Q-TOF-MS method to obtain robust information for 31 batches of ginseng samples after reasonable optimization. Subsequently, a rapid pre-processing method was established for the rapid screening and identification of 69 characteristic ginsenosides in 31 batches ginseng samples from three different origins. The SVM model successfully distinguished ginseng origin, and the accuracy of SVM model was improved from 83% to 100% by optimizing the normalization method. Six crucial quality markers for different origins of ginseng were screened using a permutation importance algorithm in the SVM model. In addition, in order to validate the method, eight batches of test samples were used to predict the regions of cultivation of ginseng using the SVM model based on the six selected quality markers. As a result, the proposed strategy was suitable for the discrimination and prediction of the origin of ginseng samples. 相似文献
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Determination of ginsenosides in Panax ginseng roots by liquid chromatography with evaporative light-scattering detection 总被引:4,自引:0,他引:4
Fuzzati N Gabetta B Jayakar K Pace R Ramaschi G Villa F Fuzzati N Gabetta B Jayakar K Pace R Ramaschi G Villa F 《Journal of AOAC International》2000,83(4):820-829
A liquid chromatographic method was developed and validated for the determination of ginsenosides in Panax ginseng roots by using evaporative light-scattering detection. Eighteen ginsenosides were separated on a reversed-phase C18 column with water-ammonium acetate-acetonitrile as the mobile phase. The method is suitable for the routine determination of ginsenosides in P. ginseng roots and extracts. The validation of the method was comprehensive for efficiency and recovery optimization of the P. ginseng roots extraction, specificity by liquid chromatography/mass spectrometry, linearity, stability, reproducibility, repeatability, intermediate precision, and robustness. 相似文献
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Nan Fang Changpeng Zhang Zhongbin Lu Zhou Lu Zhongbei Zhang Bo Wang Zhiguang Hou Xueping Zhao 《Molecules (Basel, Switzerland)》2022,27(17)
The massive use of pesticides has brought great risks to food and environmental safety. It is necessary to develop reliable analytical methods and evaluate risks through monitoring studies. Here, a method was used for the simultaneous determination of flupyradifurone (FPF) and its two metabolites in fresh ginseng, dried ginseng, ginseng plants, and soil. The method exhibited good accuracy (recoveries of 72.8–97.5%) and precision (relative standard deviations of 1.1–8.5%). The field experiments demonstrated that FPF had half-lives of 4.5–7.9 d and 10.0–16.9 d in ginseng plants and soil, respectively. The concentrations of total terminal residues in soil, ginseng plants, dried ginseng, and ginseng were less than 0.516, 2.623, 2.363, and 0.641 mg/kg, respectively. Based on these results, the soil environmental risk assessment shows that the environmental risk of FPF to soil organisms is acceptable. The processing factors for FPF residues in ginseng were 3.82–4.59, indicating that the concentration of residues increased in ginseng after drying. A dietary risk assessment showed that the risk of FPF residues from long-term and short-term dietary exposures to global consumers were 0.1–0.4% and 12.07–13.16%, respectively, indicating that the application of FPF to ginseng at the recommended dose does not pose a significant risk to consumers. 相似文献
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This study was carried out to develop a cost-, labor- and efficiency-effective elimination method of pesticide residues in ginseng extract. A two-phase partition method between soybean oil and distilled water or aqueous ginseng extract was employed for the elimination of pesticide residues. Content of the pesticides was determined by gas chromatography with electron capture or nitrogen phosphorus detector. A total of 15 pesticides representing four categories (organochlorine, organophosphorus, carbamate, pyrethroid) were spiked (ca. 2 ppm) to 2 ml soybean oil in a test tube and the oil was mixed with 6 ml distilled water or 10% aqueous ginseng extract. The test tubes were then vortexed (2 min) and centrifuged at 3000 rpm for 15 min to separate the oil and aqueous layers. Each layer was harvested and subjected to quantitative analysis of pesticides. The average distribution ratio of the pesticides to the oil layer was 94.4 +/- 6.7% in the mixture of the oil and distilled water, and 105.5 +/- 6.6% in the mixture of the oil and ginseng extract. No significant qualitative and quantitative change of ginsenosides, the active ingredients of Panax ginseng, was observed in the ginseng extract before and after the oil treatment. These results suggest that two-phase partition chromatography between soybean oil and the aqueous phase is a cost-, labor- and efficiency-effective reliable method for the elimination of pesticide residues in ginseng extract. 相似文献
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NIE Li-xing WANG Gang-li LIN Rui-chao National Institute for the Control of Pharmaceutical Biological Products Beijing P. R. China 《高等学校化学研究》2009,25(5):633-637
Near infrared spectroscopy(NIRS) was developed as a rapid analysis method for the qualitative and quantitative assessment of the quality of red ginseng. Discriminant analysis(DA) based on principal component analysis and Mahalanobis distance was used to distinguish red ginseng from counterfeits non-destructively. The result shows that the proposed method could distinguish red ginseng from counterfeits correctly and no misclassified sample was found in both training and test sets. The partial least squares(P... 相似文献
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Dong XY Kong FP Yuan GY Wei F Jiang ML Li GM Wang Z Zhao YD Chen H 《Natural product research》2012,26(6):548-556
Phytosterol liposomes were prepared using the thin film method and used to encapsulate nattokinase (NK). In order to obtain a high encapsulation efficiency within the liposome, an orthogonal experiment (L9 (3)(4)) was applied to optimise the preparation conditions. The molar ratio of lecithin to phytosterols, NK activity and mass ratio of mannite to lecithin were the main factors that influenced the encapsulation efficiency of the liposomes. Based on the results of a single-factor test, these three factors were chosen for this study. We determined the optimum extraction conditions to be as follows: a molar ratio of lecithin to phytosterol of 2?:?1, NK activity of 2500?U?mL?1 and a mass ratio of mannite to lecithin of 3?:?1. Under these optimised conditions, an encapsulation efficiency of 65.25% was achieved, which agreed closely with the predicted result. Moreover, the zeta potential, size distribution and microstructure of the liposomes prepared were measured, and we found that the zeta potential was -51?±?3?mV and the mean diameter was 194.1?nm. From the results of the scanning electron microscopy, we observed that the phytosterol liposomes were round and regular in shape and showed no aggregation. 相似文献
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Ginseng (Panax ginseng C. A. Meyer), a perennial herb, possesses immunostimulatory, anticarcinogenic, antiemetic, and antioxidative biological activities. In recent years, more and more people have paid attention to the extraction methods and quality evaluation of ginseng. China, the United States, Europe, Japan, and Korea have all had the quality standards and content determination methods of ginseng. The different treatment methods are adopted before the determination of ginseng samples and the content limits of the index components, such as ginsenoside Rb1, ginsenoside Rg1, and ginsenoside Re exist differences. The similarities and differences of ginseng content detection methods in pharmacopoeias of different countries have been analyzed by a research group, but the comparison of the effects of different methods on the ginsenoside content and structural transformation has not been reported. In this paper, ginsenosides in ginseng were extracted according to four national pharmacopoeias and analyzed quantitatively and qualitatively by UPLC-Q-Exactive-MS and HPLC-UV. It was illustrated that the pretreatment method has a significant influence on the content determination of ginseng. The yield of rare saponins was increased by heating concluded from both the qualitative and quantitative comparison. Finally, a simple and feasible extraction method was optimized by response surface method at room temperature. The analysis of the preparation method and process optimization of the four pharmacopoeias can provide important reference information for the revision of ginseng standards. 相似文献