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Simultaneous Spectrophotometric Determination of Three Components Including Deoxyschizandrin by Partial Least Squares Regression 被引量:1
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第3期119-121,共3页
The computer auxiliary partial least squares is introduced to simultaneously determine the contents of Deoxyschizandin, Schisandrin, r-Schisandrin in the extracted solution of wuweizi. Regression analysis of the exper... The computer auxiliary partial least squares is introduced to simultaneously determine the contents of Deoxyschizandin, Schisandrin, r-Schisandrin in the extracted solution of wuweizi. Regression analysis of the experimental results shows that the average recovery of each component is all in the range from 98.9% to 110.3% , which means the partial least squares regression spectrophotometry can circumvent the overlappirtg of absorption spectrums of mlulti-components, so that sctisfactory results can be obtained without any scrapple pre-separation. 展开更多
关键词 DEOXYSCHIZANDRIN partial least squares regression spectrophotometry simultaneous determination
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Study on HPLC Fingerprint and Simultaneous Determination of Three Active Components of Dipsaci Radix Collected in Different Time 被引量:1
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作者 Pu CHEN Xiangluan WAN +2 位作者 Hua ZHAO Yujie CHEN Dingrong WAN 《Medicinal Plant》 CAS 2019年第2期35-38,共4页
[Objectives] To establish methods of HPLC fingerprint and simultaneous determination of the three bioactive components(namely, asperosaponin VI, loganin and sweroside) of Dipsaci Radix, and explore the quality situati... [Objectives] To establish methods of HPLC fingerprint and simultaneous determination of the three bioactive components(namely, asperosaponin VI, loganin and sweroside) of Dipsaci Radix, and explore the quality situation of this crude medicine collected in various months in autumn. [Methods] The analysis was performed on Thermo BDS Hypersil C_(18)(4.6 mm×250 mm, 5 μm) column with a mixture of acetonitrile and 0.1% phosphoric acid as mobile phase in gradient mood at a flow rate of 1.0 mL/min, the column temperature was set at 30 ℃, and the detection wavelength was 220 nm. [Results] The analysis methods for HPLC fingerprint and determination of the three components in Dipsaci Radix had been established. The results showed that 12 batches of samples, which were collected in four different places from September to November, possessed the similarities of greater than 0.976. Through the quantitative analysis of asperosaponin VI, loganin and sweroside in Dipsaci Radix, it was found that the quality variation of this herbal medicine and the different collected months of autumn showed a low correlation. [Conclusions] The established methods of HPLC characteristic fingerprint and simultaneous determination of three glycosides provided a new way for quality analysis of Dipsaci Radix. It was preliminarily indicated that collecting this plant medicine in different months of autumn would not affect its quality. 展开更多
关键词 Dipsaci RADIX HPLC FINGERPRINT Asperosaponin VI LOGANIN Sweroside CONTENT determination
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Multicomponent Kinetic Determination by Wavelet Packet Transform Based Elman Recurrent Neural Network Method 被引量:1
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作者 RENShou-xin GAOLing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期698-702,共5页
This paper covers a novel method named wavelet packet transform based Elman recurrent neural network(WPTERNN) for the simultaneous kinetic determination of periodate and iodate. The wavelet packet representations of s... This paper covers a novel method named wavelet packet transform based Elman recurrent neural network(WPTERNN) for the simultaneous kinetic determination of periodate and iodate. The wavelet packet representations of signals provide a local time-frequency description, thus in the wavelet packet domain, the quality of the noise removal can be improved. The Elman recurrent network was applied to non-linear multivariate calibration. In this case, by means of optimization, the wavelet function, decomposition level and number of hidden nodes for WPTERNN method were selected as D4, 5 and 5 respectively. A program PWPTERNN was designed to perform multicomponent kinetic determination. The relative standard error of prediction(RSEP) for all the components with WPTERNN, Elman RNN and PLS were 3.23%, 11.8% and 10.9% respectively. The experimental results show that the method is better than the others. 展开更多
关键词 Wavelet packet transform Elman recurrent neural network Multicomponent kinetic determination
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Development and Validation of an HPLC Method for Simultaneous Determination of Nine Active Components in ‘Da-Chai-Hu-Tang’ 被引量:1
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作者 Lingli Zheng Deshi Dong 《Chinese Medicine》 2011年第1期20-28,共9页
In this study, a simple, reliable and accurate method for the simultaneous separation and determination of naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein, wogonin, emodin and chrysophanol in ‘Da... In this study, a simple, reliable and accurate method for the simultaneous separation and determination of naringin, hesperidin, neohesperidin, baicalin, wogonoside, baicalein, wogonin, emodin and chrysophanol in ‘Da-Chai-Hu-Tang’ was developed by reverse-phase high-performance liquid chromatography (RP-HPLC). The chromatographic separation was performed on an Agilent ZORBAX C18 column (250 mm × 4.6 mm i.d., 5.0 μm), and the mobile phase composed of methanol and water containing 1% (v/v) acetic acid was used to elute the targets in a gradient elution mode. The flow rate and detection wavelength were set at 0.8 ml/min and 280 nm, respectively. All calibration curves of the nine components expressed good linearities (r2≥0.9992) within the tested ranges. The RSD values demonstrated the intra- and inter-day precisions were less than 2.89%, and the recoveries of the investigated compounds were between 96.22% and 105.28%. The proposed method is simple, precise, specific, sensitive, and successfully applied to determine the nine marker compounds in ‘Da-Chai-Hu-Tang’ for quality control. 展开更多
关键词 High-performance liquid CHROMATOGRAPHY 'Da-Chai-Hu-Tang’ Traditional Chinese MEDICINE Multiple compounds determination
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Determination of the Contents of Seven Chemical Components in Vidal Grape by Quantitative Analysis of Multi-components by Single Marker(QAMS) 被引量:1
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作者 Shizhao XU Fei QI +2 位作者 Yalin XI Ling WU Weijia SUN 《Agricultural Biotechnology》 CAS 2020年第6期131-135,共5页
[Objectives]This study was conducted to establish a method of quantitative analysis of multi-components by single marker(QAMS)for the simultaneous determination of such seven chemical components as gallic acid,epicate... [Objectives]This study was conducted to establish a method of quantitative analysis of multi-components by single marker(QAMS)for the simultaneous determination of such seven chemical components as gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin and caffeic acid in Vidal grape.[Methods]The high performance liquid chromatography was carried out using a COSMOSIL C18-MS-II column(4.6 mm×250 mm,5μm)with the mobile phase acetonitrile-2%acetic acid aqueous solution(gradient elution)at a flow rate of 1.0 ml/min.The detection wavelength was 280 nm,and the column temperature was 25℃.Using caffeic acid as an internal reference,the relative correction factors between it and other six to-be-detected components,and the contents of the seven components were calculated using the correction factors.The established was compared the results with the external standard method to verify the feasibility and accuracy of the method.[Results]The seven components had a good linear relationship in the ranges of 1.060-10.60,1.419-14.19,1.062-10.62,0.2950-2.950,0.1019-1.019,0.2014-2.014,and 0.1498-1.498μg,respectively,and the relative correction factors of gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid and rutin were 0.9760,0.7806,0.3277,1.640,1.161,2.778,respectively.There was no significant difference between the results of the QAMS method and the external standard method.[Conclusions]The QAMS method using caffeic acid as an internal reference is accurate and feasible,and provides a reliable method for the quality evaluation of Vidal ice grape. 展开更多
关键词 High performance liquid chromatography Vidal grape Content determination Polyphenol compounds
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Simultaneous Spectrophotometric Determination of Four Components including Acetaminophen by Taget Factor Analysis
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第3期569-571,共3页
UV Spectrophotometric Target Factor Analysis (TFA) was used for the simultaneous determination of four components (acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate) in cough syrup. The computer Frogra... UV Spectrophotometric Target Factor Analysis (TFA) was used for the simultaneous determination of four components (acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate) in cough syrup. The computer Frogram of TFA is based on VC++ language. The difficulty of overlapping of absorption spectra of four compounds was overcome by this procedure. The experimental results show that the average recovery of each component is all in the range from 98.9% to 106.8% and each component obtains satisfactory results without any pre-separation. 展开更多
关键词 ACETAMINOPHEN taget factor analysis SPECTROPHOTOMETRY four-component simultaneous determination
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Simultaneous Determination of Five Components Including Acetaminophen by Reversed-phase High Performance Liquid Chromatography
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第1期34-35,共2页
High performance liquid chromatography with a C18 reverse-phase column was used to separate the five components in cough syrup,including acetaminophen,p-aminophenol,caffeine,chlorphenamine maleate and guaifenesin.The ... High performance liquid chromatography with a C18 reverse-phase column was used to separate the five components in cough syrup,including acetaminophen,p-aminophenol,caffeine,chlorphenamine maleate and guaifenesin.The mobile phase consists of 15wt% acetonitrile,0.004mol/L sodium heptyl sulfonate, 0.03mole/L potassium di-hydrogen phosphate and triethylamine (volume ratio 13∶40∶44∶3),the pH of which is adjusted to 3.0 by phosphoric acid.The contents of the five components are analyzed on an ultraviolet spectrophotometer at 254nm,with a flow rate of 0.4mL/min.The results show that the calibration curves are linear in a certain range.The average recovery of five components is between 96.31% and 102.3%. 展开更多
关键词 organic compounds preparation and determination CHROMATOGRAPHY
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Determination of Photoelastic Constant Ratio of the Two Components in Ge_(x)Si_(1-x)/Si Superlattice
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作者 JIN Ying ZHANG Shulin +2 位作者 ZHOU Guoliang YU Mingren QIN Guogang 《Chinese Physics Letters》 SCIE CAS CSCD 1992年第4期213-216,共4页
From the intensity ratio of the folded longitudinal acoustic phonons with respect to the longitudinal acoustic phonon in a Ge_(0.51)Si_(0.49)/Si superlattice(SL),we obtained a photoelastic constant ratio of 6.6 for Ge... From the intensity ratio of the folded longitudinal acoustic phonons with respect to the longitudinal acoustic phonon in a Ge_(0.51)Si_(0.49)/Si superlattice(SL),we obtained a photoelastic constant ratio of 6.6 for Ge_(0.51)Si_(0.49) alloy with respect to Si in the SL at wavelength 5145 A,which is 2.6 times greater than that obtainedby[He Phys.Rev.B 39(1989)5919]in a Ge_(0.5)Si_(0.5)/Si SL. 展开更多
关键词 alloy determination
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Simultaneous Determination of Six Components in Cortex Phellodendri by HPLC
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作者 Lian LIAN Guosheng WAN +1 位作者 Weili JIA Huiyuan GAO 《Agricultural Biotechnology》 CAS 2023年第2期87-90,共4页
[Objectives]This study was conducted to establish the method for simultaneous determination of six active components.[Methods]Simultaneous determination of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,pa... [Objectives]This study was conducted to establish the method for simultaneous determination of six active components.[Methods]Simultaneous determination of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine in Cortex Phellodendri was carried out by HPLC with a Diamonsil C18(4.6 mm×250 mm,5μm)column was used.The mobile phase was acetonitrile-water(1‰acetic acid,2 mmol ammonium acetate)solution in gradient elution.The detection wavelength was set at 280 nm,and the column temperature was kept at 25℃and the flow rate was 1 ml/min.[Results]The linear ranges of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine were 20.00-320.00,18.75-130.00,25.00-200.00,5.00-100.00,20.00-200.00,and 0.09-1.80 mg/L,respectively.The average recovery was 98.1%,99.4%,97.5%,97.3%,104.0%,and 98.5%,respectively;and the RSDs were 0.5%,0.6%,0.8%,1.0%,1.4%,and 0.9%,respectively.[Conclusions]The method is convenient,stable,reliable and suitable for quality control of Cortex Phellodendri. 展开更多
关键词 Cortex Phellodendri Chlorogenic acid Phellodendrine MAGNOFLORINE JATRORRHIZINE PALMATINE BERBERINE determination
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Simultaneous Determination of Effective Components of Gegen Qinlian Tablets by HPLC
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作者 Lili LI Yifeng LU Xueyan ZHU 《Medicinal Plant》 CAS 2020年第1期24-28,36,共6页
[Objectives]To establish a HPLC method for the simultaneous determination of 14 characteristic components in Gegen Qinlian tablets and the content of Gegen Qinlian tablets in 11 manufacturers.[Methods]A Inertsil ODS-3... [Objectives]To establish a HPLC method for the simultaneous determination of 14 characteristic components in Gegen Qinlian tablets and the content of Gegen Qinlian tablets in 11 manufacturers.[Methods]A Inertsil ODS-3(250 mm×4.6 mm,5μm)reversed-phase high performance liquid chromatography column was used with acetonitrile-0.02 mol/L ammonium acetate+0.03%triethylamine solution(adjusted with glacial acetic acid to pH of 4.3)as the mobile phase for gradient elution at a flow rate of 1.0 mL/min.The determination wavelength of 8 components(puerarin,daidzin,liquiritin,baicalin,wogonoside,daidzein,ammonium glycyrrhizinate,baicalein)was 250 nm;the determination wavelength of wogonoside was 280 nm;the determination wavelength of 5 components(epierberine,jatrorrhizine hydrochloride,coptisine,palmatine hydrochloride and berberine hydrochloride)was 346 nm.[Results]There was a good linear relationship between the injection volume of puerarin,daidzin,liquiritin,baicalin,wogonoside,epierberine,jatrorrhizine hydrochloride,coptisine,daidzein,palmatine hydrochloride,ammonium glycyrrhizinate,berberine hydrochloride,baicalein and wogonin and peak area(r>0.9990)in the range of 146.26-5850.24,24.13-965.04,18.45-738.00,79.18-3167.32,9.57-382.80,4.76-190.40,2.57-102.80,13.41-536.40,10.60-424.00,11.33-453.22,12.08-483.20,46.73-1869.25,20.28-811.20,12.11-484.50 ng,respectively;the average recovery rates(n=6)were 2.18%,1.79%,1.81%,1.68%,2.27%,2.13%,1.96%,1.07%,0.93%,0.61%,2.92%,0.77%,2.79%and 0.62%,respectively;the precision,repeatability and stability were good,and the RSD was less than 3%.This method was used to determine 16 batches of Gegen Qinlian tablets produced by 11 enterprises.Wogonoside was not detected in a lot of samples,but 14 components were detected for other enterprises,but the content was different.[Conclusions]The method was accurate and feasible and could be used for the overall quality control of this variety. 展开更多
关键词 Gegen Qinlian tablets Content determination High performance liquid chromatography Puerarin DAIDZIN Liquiritin Baicalin WOGONOSIDE Epierberine JATRORRHIZINE HYDROCHLORIDE COPTISINE Daidzein PALMATINE HYDROCHLORIDE Ammonium glycyrrhizinate Berberine HYDROCHLORIDE Baicalein Wogonin
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Simultaneous determination of ten components in Dianxiankang Capsules by HPLC QAMS
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作者 GUANG Li-wen ZHANG Shuang +1 位作者 GAO Xin-lei YANG Tian-ming 《Journal of Hainan Medical University》 2022年第18期13-21,共9页
Objective:To establish an high performance liquid chromatography-quantitative analysis of multi components by single marker(HPLC-QAMS)method for simultaneous determination of gastrodin,parishin E,parishin B,parishin,t... Objective:To establish an high performance liquid chromatography-quantitative analysis of multi components by single marker(HPLC-QAMS)method for simultaneous determination of gastrodin,parishin E,parishin B,parishin,tenuifolin,onjisaponin B,methylophiopogonanone A,methylophiopogonanone B,β-asarone andαasarone in Dianxiankang Capsules.Methods:Waters Symmetry C_(18)column was used with acetonitrile-0.05%phosphoric acid solution as mobile phase for gradient elution.Multiwavelength switching detection.The contents of gastrodin,parishin E,parishin B,parishin,onjisaponin B,methylophiopogonanone A,methylophiopogonanone B,β-asarone andα-asarone were calculated by relative correction factor.At the same time,the contents of 10 components in 12 batches of Dianxiankang Capsules were determined by external standard method(ESM).Results:An HPLC-QAMS method was established tenuifolin as the internal reference substance was established.The relative correction factors of gastrodin,parishin E,parishin B,parishin,onjisaponin B,methylophiopogonanone A,methylophiopogonanone B,β-asarone andα-asarone were 0.8238,0.7239,1.0229,1.1881,0.7272,1.3108,0.9314,0.6549 and 1.0572,respectively.The relative correction factors had good repeatability and no significant difference with ESM(P>0.05).Conclusion:HPLC-QAMS can be used for simultaneous determination of multi-index components in Dianxiankang Capsules. 展开更多
关键词 HPLC QAMS Dianxiankang Capsules f_(k/s) Quantitative determination
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SIMULTANEOUS DETERMINATION OF MULTICOMPONENT IN MIXED ACIDS BY MATHEMATICAL METHOD
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作者 Yong Nian NI Department of Chemistry,Jiangxi University,Nanchang,330047 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期105-108,共4页
A new method for the determination of components in mixed acids has been developed.The mathematical model is obtained from samples of known composition and is then used to predict the concentrations of components in u... A new method for the determination of components in mixed acids has been developed.The mathematical model is obtained from samples of known composition and is then used to predict the concentrations of components in unknown sample.The practical utility of this method is demonstrated for simultaneous determination of two systems of ternary mixed acids and the results are satisfactory. 展开更多
关键词 ACID SIMULTANEOUS determination OF MULTIcomponent IN MIXED ACIDS BY MATHEMATICAL METHOD
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Determination of the Content of Five Active Components in Toad Skin
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作者 Xue JIANG Wenli LI +1 位作者 Yong CHEN Jiabao MA 《Medicinal Plant》 CAS 2023年第4期38-40,共3页
[Objectives] To establish a method for the determination of active components in toad skin. [Methods] HPLC method was used to determine the content of five active components (bufotalin, cinobufotalin, bufalin, cinobuf... [Objectives] To establish a method for the determination of active components in toad skin. [Methods] HPLC method was used to determine the content of five active components (bufotalin, cinobufotalin, bufalin, cinobufagin and resibufogenin) in toad skin. [Results] Chromatographic conditions are as follows: Agilent ZORBAX SB-C 18 chromatographic column was used;acetonitrile (A)-0.3% glacial acetic acid (B) gradient elution (0-15 min, 28%A-54%A;15-35 min, 54%A-54%A) was conducted;the flow rate was 0.6 mL/min;the detection wavelength was 296 nm;the column temperature was 30 ℃;the sample size was 10 μL. Under the above conditions, the determination method of the five components can be established at one time. [Conclusions] The method was stable and reliable, and can provide experimental basis for the development and utilization of active ingredients in toad skin. 展开更多
关键词 Toad skin High performance liquid chromatography determination of content
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Simultaneous Determination of Six Active Components of Smilacis Glabrae Rhizome by UPLC-DAD
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作者 Muhua YUAN Zijiang YANG +3 位作者 Dingqiao CHEN Zhigang YAN Lili HE Zhifeng ZHANG 《Medicinal Plant》 2017年第5期20-22,33,共4页
[Objectives] To determine the content of neoastilbin,astilbin,neoisoastilbin,isoastilbin,engeletin,and resveratrol in Smilacis glabrae rhizome. [Methods] The ultra-high-performance liquid chromatography method with di... [Objectives] To determine the content of neoastilbin,astilbin,neoisoastilbin,isoastilbin,engeletin,and resveratrol in Smilacis glabrae rhizome. [Methods] The ultra-high-performance liquid chromatography method with diode array detection( UPLC-DAD) was developed. Analysis conditions as follows: waters Acquity UHPLC HT3 C18 chromatographic column( 2.1 × 100 mm),column temperature 30 ℃,mobile phase acetonitrile( A)-0.1% phosphoric acid( B) gradient elution,flow rate 0.2 mL/min,and detection wavelength 327 nm. [Results]Results indicated that the content of astilbin,neoastilbin,isoastilbin,neoisoastilbin,engeletin,and resveratrol in 10 samples of Smilacis glabrae rhizome was 1.313-6.1755 mg,0.013-3.699 mg,0.146-0.975 mg,0.137-0.7 mg,0.147-0.797 mg,0.077-0.112 mg,respectively. [Conclusions]This method is high efficient,convenient and accurate,and can be used as the method for quality control of Smilacis glabrae rhizome. 展开更多
关键词 Smilacis glabrae RHIZOME UHPLC determination
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Determination of Active Components of Lamiophlomis rotata(Benth.)Kudo by Ultra-performance Convergence Chromatography
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作者 Guilin JIN Shijun SHAO Fude YANG 《Medicinal Plant》 CAS 2020年第5期19-22,共4页
[Objectives]To determine active components of Lamiophlomis rotata(Benth.)Kudo.[Methods]A new method was developed for the quantitative determination of L.rotata by using Ultra-performance convergence chromatography.Th... [Objectives]To determine active components of Lamiophlomis rotata(Benth.)Kudo.[Methods]A new method was developed for the quantitative determination of L.rotata by using Ultra-performance convergence chromatography.The separation of active components of L.rotata was successfully achieved on Waters ACQUITY UPC column,with gradient elution carbon dioxide and methanol solvent at flow rate of 0.7 mL/min.The separation gradient elution rate was as follows:15%methanol 0-1 min,18%methanol 1-5 min,20%methanol 5-6 min,25%methanol 6-7 min,30%methanol 7-8 min,30%methanol 8-9 min,15%methanol 9-10 min.The conditions used in the separation process was as follows:column temperature 30℃;injection volume 2μL.Under the abovementioned conditions,the content of methyl glucoside was measured by 3D-full wavelength scanning.The validity of the method was tested by analyzing the precision,reproducibility,stability and accuracy.[Results]The results indicated that in terms of extraction and separation of compounds,supercritical CO2 not only has the diffusion property of gas,but also has the density and fluidity of liquid.[Conclusions]The ultra-high performance chromatography is a new technique for drug analysis. 展开更多
关键词 Lamiophlomis rotata(Benth.)Kudo Waters UPC2 Active components Content determination New method
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Sex Determination in Homo sapiens as a Multi-Step Process: Potential for Development of Variants and Sex Differences in Disease Risk
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作者 David A. Hart 《Journal of Biomedical Science and Engineering》 2024年第1期13-34,共22页
Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific ... Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific approach has been a successful strategy for survival of a large variety of species including humans, the fidelity of sex determination leading to 100% cis-binary outcomes is not achieved in many species, with evidence for homosexual or bisexual behaviour evident in more than 1500 species. Thus, such outcomes indicates that sex determination is a multi-step process and not a single event, and as such, could lead to the appearance of variants during the process which developed much earlier than humans. Variants could arise either due to intrinsic variation in the steps of determination, or also be influenced by environmental factors of a biological or psychological nature. In contrast to homosexual variants which do not require interventions such as hormone therapy or surgery, expression of gender dysphoria, is more based in psychology, but also has biological underpinnings and can be influenced by such hormonal interventions and surgery. While the numbers of those with gender dysphoria is small (~0.6% - 1.0% of population), the attention given to this issue raises the possibility of biological and psychological environmental factors impacting the emergence of some of those expressing gender dysphoria. Furthermore, transitioning from male-to-female or female-to-male can have consequences regarding disease risks latter in life, including the appearance of autoimmune diseases. This review will attempt to review some of the evidence regarding sex determination, discuss why the system has potentially not been improved upon during evolution, how a potential role for sex chromosome function on neurodevelopment may be central to variation in humans, and how commitment to the current strategy is likely integrated into other sex-related events such as puberty, pregnancy, and menopause to ensure species survival. It will also discuss how variants in sex determination could contribute to sex differences in disease risk and how epigenetic modifications could play a role in such risk. . 展开更多
关键词 Sex determination Variant Development Fidelity of Sex determination Biological Sex determination Species Variation
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Determination of potassium content as principal components in pyrotechnic compositions used for fireworks and firecrackers based on inductively coupled plasma optical emission spectrometric approach (ICP-OES)
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作者 Xiao Huan-xin Wu Jun-yi 《International Journal of Technology Management》 2014年第2期87-90,共4页
Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element ... Inductively coupled plasma optical emission spectrometric approach(1CP-OES) is used to determine the potassium content as principal component in pyrotechnic compositions used for fireworks and firecrackers. Element of potassium is conunonly found in potassium nitrate and potassium perchlorate in pyrotechnic compositions in fireworks and firecrackers. Statistical analysis shows that potassium nitrate content in pyrotechnics is between 10% to 60% and the potassium perchlorate content is between 20% to 70%,which counted in the content of potassium element is between 4% to 23%. Concept of this method: considering the weight of the sample is 400rag,constant volume is 1L and the concentration of potassium is between 10 mg/L to 90 mg/L in sample solution, the determination scope of the method for the potassium content would be between 1% to 23%.Further experiments proved that the fitting correlation coefficient of potassium calibration curve is 0.9997 or higher, recovery is 89.15%-100.23%.The allowable differential value is 0.4% between two single tests under repeatable conditions. This method can completely satisfy the requirements of the fireworks and firecrackers industry with high accuracy and good precision. 展开更多
关键词 fireworks and firecrackers pyrotechnic compositions principal component POTASSIUM content determination inductively coupled plasma optical emission spectrometric approach ICP-OES.
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Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales
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作者 Qin Ma Zizhen Fan +5 位作者 Ping Wang Siya Ma Jian Wen Fengqin Cao Xianwu Lin Rihui Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期938-947,共10页
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi... transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control. 展开更多
关键词 Zeugodacus cucurbitae TRANSFORMER transformer-2 sex determination RNA interference biological control
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Relative orbit determination algorithm of space targets with passive observation
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作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
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The Impact of Sleep Determination on Procrastination before Bedtime:The Role of Anxiety
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作者 Na Liu Junxiu Wang Wanli Zang 《International Journal of Mental Health Promotion》 2024年第5期377-387,共11页
Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of ... Objective:The importance of good sleep for energy recovery and overall physical and mental health cannot be overstated.However,the increasing competitiveness of society,diversifying lifestyles,and the rapid spread of the internet and electronic devices have significantly impacted people’s sleep patterns,particularly through bedtime procrastination.Therefore,this study aims to investigate the relationship and underlying mechanisms between sleep determination,anxiety,and bedtime procrastination among the Chinese population.Method:The study utilized data from a national survey—the China Residents’Sleep Condition Survey(November 2021,with 6,037 participants).By constructing mediation and moderation models,it analyzed the relationship and mechanisms between sleep determination and bedtime procrastination,highlighting the dual role of anxiety:as a mediator between sleep determination and bedtime procrastination,and as a moderator of their relationship.Results:There was a negative correlation between sleep determination and bedtime procrastination;anxiety was related to an increase in bedtime procrastination behaviors;In the interplay between sleep determination and pre-bedtime procrastination,the regulatory effect of anxiety is found to be more pronounced than its intermediary role,with anxiety significantly diminishing the inverse relationship between sleep determination and procrastination before bedtime.Conclusion:Bedtime procrastination can lead to sleep issues,thus reducing sleep quality.Enhancing sleep determination or alleviating pre-sleep anxiety can help inhibit bedtime procrastination behaviors.Intervening and reducing bedtime procrastination is one of the effective measures to improve sleep quality. 展开更多
关键词 Sleep determination bedtime procrastination ANXIETY MEDIATION moderation
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