[Objectives]To explore the methods for identifying pure honey.[Methods]Using 35 batches of Jiulongteng honey sourced from various production areas in Guangxi as the research subjects,this study investigated the chromo...[Objectives]To explore the methods for identifying pure honey.[Methods]Using 35 batches of Jiulongteng honey sourced from various production areas in Guangxi as the research subjects,this study investigated the chromogenic reactions of starch and dextrin,as well as the comparative study of thin-layer chromatography of oligosaccharides present in Jiulongteng honey.[Results]None of the 35 batches of Jiulongteng honey samples exhibited blue(indicating starch),green,or reddish-brown(indicating dextrin)coloration,suggesting that no adulterants such as artificially added starch,dextrin,or sugar were present in these samples.Furthermore,none of the 35 batches displayed additional spots below the corresponding positions of the control,indicating that the sugar composition was consistent with the oligosaccharide profile of natural honey.No components inconsistent with the oligosaccharide profile of natural honey were detected.Therefore,it can be concluded that the Jiulongteng honey samples in this experiment were pure and free from adulteration with starch,dextrin,or other sugar substances.[Conclusions]The method employed in this experiment is straightforward and quick to implement,effectively preventing adulterated honey from entering the market.It enhances the efficiency of quality control for Jiulongteng honey and promotes the healthy development of the Jiulongteng honey industry.展开更多
In this study,a high performance thin-layer chromatography/single quadrupole mass spectrometry QDa(HPTLC-QDa)method for robust authentication of Ganoderma lucidum,a popular and valuable herbal medicine,has been develo...In this study,a high performance thin-layer chromatography/single quadrupole mass spectrometry QDa(HPTLC-QDa)method for robust authentication of Ganoderma lucidum,a popular and valuable herbal medicine,has been developed.This method is simple and practical,which allows direct generation of characteristic mass spectra from the HPTLC plates automatically with the application of in situ solvent desorption interface.The HPTLC silica gel plates were developed with toluene-ethyl formate-formic acid(5:5:0.2,V/V)and all bands were transferred to QDa system directly in situ using 80%methanol with 0.1%formic acid as desorption solvent.The acquired HPTLC-QDa spectra showed that luminous yellow band b3,containing ganoderic acid B/G/H and ganodeneric acid B,the major active components of Ganoderma,could be found only in G.lucidum and G.lucidum(Antler-shaped),but not in G.sinense and G.applanatum.Moreover,bands b13 and b14 with m/z 475/477 and m/z 475/491/495,respectively,could be detected in G.lucidum(Antler-shaped),but not in G.lucidum,thus allowing simple and robust authentication of G.lucidum with confused species.This method is proved to be simple,practical and reproducible,which can be extended to analyze other herbal medicines.展开更多
The holistic characterization and quality control of all the medicinal herbs of proprietary Chinese medicines(PCMs)are of great significance to ensure their safety,efficacy,and consistency.Thin-layer chromatography(TL...The holistic characterization and quality control of all the medicinal herbs of proprietary Chinese medicines(PCMs)are of great significance to ensure their safety,efficacy,and consistency.Thin-layer chromatography(TLC),a simple and classic approach for qualitatively characterizing and examining quality markers of natural products,has been widely used in the characterization and quality control of traditional Chinese medicines.Zaoren Anshen(ZRAS)capsule,prepared from three medicinal herbs of fried Ziziphi Spinosae Semen,Salvia Miltiorrhiza Radix et Rhizoma,and vinegar-processed Schisandrae Chinensis Fructus,is a famous PCM in China for the treatment of insomnia,amnesia,and dizziness in clinical practice.However,no effective method is available so far for simultaneous identification and examination of all the three medicinal herbs of ZRAS capsule.In the present study,we developed a TLC method via twice-development and visualization by UV light or chromogenic agent,which could be used for simultaneous qualitative identification of all the three medicinal herbs of ZRAS capsule in one plate.Moreover,the sample preparation method was optimized.The developed TLC method was rapid,simple,low-cost,and effective,and thus it could be used for quality control of ZRAS capsule.展开更多
Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance pr...Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids.展开更多
[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L...[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L. franchetii from different localities were determined according to the methods described in Chinese Pharmacopoeia( 2015 Edition). [Results] In the 10 samples,the contents of moisture were all less than or equal to 15. 0%; the contents of total ash were all below 12. 0%; and the contents of acid-insoluble ash were all less than 3. 0%. The contents of water-soluble extract( by cold-soaked extraction method) in the samples were all below 12. 0% except those from Hongyuan Prairie of Sichuan Province and Xinglong Mountain in Lanzhou City,Gansu Province. [Conclusions]The contents of the four indicators measured in this experiment varied by small margins,indicating that the quality was relatively stable. This study provides theoretical data for the revision of the quality standards for L. franchetii.展开更多
A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography pl...A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity.展开更多
ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused....ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused. The solvent System was petroleum ether-ethyl acetate-glacial acetic acid (8o:20:1) and the spra-ying reagent was a solution of sulphuric acid and vanillin. Under the selected con-ditions, the peak area was linearly related to the cholesterol amount for the range between 80~700 ng per spot. The intraplate and interplate coefficients were 2.4% and 7.4% respectively. The recovery of cholesterol was 101.6%. The method presented was simple, rapid and accurate. The results of experi-mental investigation and clinical application were satisfactory.展开更多
Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine....Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine. Since the isocratic elution method cannot be applied successfully in TLC analysis for separating all the nucleoside components, the stepwise gradient elution has been developed in this work to separate eight nucleoside standards with success. In this way, quantitative analyses of the samples of Cordyceps sinensis were achieved via the pro-posed TLC procedure coupled with the scanning densitometric techniques of CAMAG and TLCQA methods for qualitative and quantitative analysis.展开更多
Objective:Belamcandae Rhizoma and Iridis Tectori Rhizoma are easily confused with each other.The main objective of this study is to distinguish them using chemical analysis.Materials and Methods:Thin-layer chromatogra...Objective:Belamcandae Rhizoma and Iridis Tectori Rhizoma are easily confused with each other.The main objective of this study is to distinguish them using chemical analysis.Materials and Methods:Thin-layer chromatography(TLC)and high-performance liquid chromatography(HPLC)fingerprint methods were established to compare the chemical profile,while HPLC quantitation was used to determine the contents of three isoflavones in thirty batches of Belamcandae Rhizoma and Iridis Tectori Rhizoma samples.Results:The two herbs could be distinguished by TLC using acetic acid-n hexane-ethyl acetate(1:90:80 v/v/v)as the mobile phase,according to the fluorescent band under 366 nm at R_(f) 0.2.In total,12 compounds were identified in the 24-min HPLC fingerprint.The similarity coefficient between the two herbs was 0.54±0.01.Mangiferin(1),tectoridin(2),iridin(3),irigenin(5),irisflorentin(6),and iristectorin A(9)were the main peaks in Belamcandae Rhizoma,while tectoridin(2)and tectorigenin(4)were the major peaks in Iridis Tectori Rhizoma.The contents of 2 in Iridis Tectori Rhizoma(2.50±0.20%)were 8.93 times higher than that of Belamcandae Rhizoma(0.28±0.08%),while the ones of 5 and 6 were slightly lower in Iridis Tectori Rhizoma.Conclusions:The study established fast and effective methods to distinguish Belamcandae Rhizoma from Iridis Tectori Rhizoma.展开更多
A specific, precise and stability indicating high-performance thin-layer chromatographic method for simultaneous estimation of pantoprazole sodium and itopride hydrochloride in pharmaceutical formulations was develope...A specific, precise and stability indicating high-performance thin-layer chromatographic method for simultaneous estimation of pantoprazole sodium and itopride hydrochloride in pharmaceutical formulations was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60F254 as the stationary phase. The solvent system consisted of methanol:water:ammonium acetate; 4.0:1.0:0.5 (v/v/v). This system was found to give compact and dense spots for both itopride hydrochloride (Rf value of 0.55__+0.02) and pantoprazole sodium (Rf value of 0.85+0.04). Densitometric analysis of both drugs was carried out in the reflectance- absorbance mode at 289 nm. The linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9988___0.0012 in the concentration range of 100--400 ng for pantoprazole sodium. Also, the linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9990_+0.0008 in the concentration range of 200-1200 ng for itopride hydrochloride. The method was validated for specificity, precision, robustness and recovery. Statistical analysis proves that the method is repeatable and selective for the estimation of both the said drugs. As the method could effectively separate the drug from its degradation products, it can be employed as a stability indicating method.展开更多
A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer ...A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer chromatograpic scanner in zig-zag dual-wavelength reflection mode.Detection sensitivity for strychniue was about 0. 05 μg. Quantification recoveries were between89. 2% and 99. 5% with RSD between 2. 92% and 13. 21 %. The method was applied to investigate thedistribution or strychnine in intoxicated rats. The results showed that there were remarkable difference in organs or tissues with the aigaest concentration 4. 56±1. 41μg/g in liver. Diversification experiment proves the method also could be used to analyze other alkaloids in biological samples if theconditions slightly modified.展开更多
Silica gel thin-layer plates covered with L-arginine and copper acetate were used for the separation of amino acid enantiomers, The chromatographic selectivity and the effects of plate different preparation methods, s...Silica gel thin-layer plates covered with L-arginine and copper acetate were used for the separation of amino acid enantiomers, The chromatographic selectivity and the effects of plate different preparation methods, sample molecular structure and solvent compositions on resolution performance were also discussed.展开更多
Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recentl...Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recently,more and more thin-layer super-heavy oil reservoirs have been discovered in China,while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply,so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil.To this end,this paper focuses on the enlightenment of field application in SAGD technology.Firstly,based on typical SAGD field projects,the development history of SAGD technology in the world was reviewed,and the influence of reservoir physical properties on the application of SAGD technology in thin-layer superheavy oil reservoirs was analyzed.Secondly,the well pattern,wellbore structure,pre-heating,artificial lift,and monitor technique of SAGD were detailed described,and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs.Lastly,the gas-and solventassistant SAGD were comprehensively evaluated,and their application potential in thin-layer superheavy oil reservoirs was studied.The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.展开更多
Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages i...Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism bears great meaning for its development and utilization. The effects of temperature and microwave cracking in municipal sewage sludge drying characteristics are stud- ied through municipal sewage sludge drying experiment. Experiments shows that higher drying temperature would lead to a more acutely changing drying rate (DR). The DR had increased from 0.005 g/(g.min) to 0.060 g/(g·min), which was 12 times enlarged, while the temperature rose from 70℃ to 160 ℃. The higher the temperature was, the earlier the peak value of DR appeared. The experiments indicated that the temperature was the decisive factor affecting the DR. The microwave-induced sludge reached the highest DR at the moisture rate (MR) of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the DR was rising in proportion to the microwave radiation dose. The diffusion coefficient had been calculated according to Fick's law. In com- parison to that of the original one, the diffusion coefficient of microwave-induced sludge was obviously enlarged more than two times. By fit examinations, Model Weibull was proven to be the most fit one for thermal thin-layer drying of municipal sludge. By means of Arrhenius equation, the obtained average activation energy of municipal sludge was 37.1 kJ/(mol·K).展开更多
Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile ph...Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids.展开更多
Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the control...Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin.展开更多
Bioreactive thin-layer capping(BTC)with biozeolite provides a potential remediation design that can sustainably treat N contamination from sediment and overlying water in eutrophic water bodies.Nitrogen(N)reductio...Bioreactive thin-layer capping(BTC)with biozeolite provides a potential remediation design that can sustainably treat N contamination from sediment and overlying water in eutrophic water bodies.Nitrogen(N)reduction using BTC with biozeolite was examined in a field incubation experiment in a eutrophic river in Yangzhou,Jiangsu Province,China.The biozeolite was zeolite with attached bacteria,including two isolated heterotrophic nitrifiers(Bacillus spp.)and two isolated aerobic denitrifiers(Acinetobacter spp.).The results showed that the total nitrogen(TN)reduction efficiency of the overlying water by BTC with biozeolite(with thickness of about 2 mm)reached a maximum(56.69%)at day 34,and simultaneous heterotrophic nitrification and aerobic denitrification occurred in the BTC system until day 34.There was a significant difference in the TN concentrations of the overlying water between biozeolite capping and control(t-test;p〈0.05).The biozeolite had very strong in situ bioregeneration ability.Carbon was the main source of nitrifier growth.However,both dissolved oxygen(DO)and carbon concentrations affected denitrifier growth.In particular,DO concentrations greater than 3 mg/L inhibited denitrifier growth.Therefore,BTC with biozeolite was found to be a feasible technique to reduce N in a eutrophic river.However,it is necessary to further strengthen the adaptability of aerobic denitrifiers through changing domestication methods or conditions.展开更多
The construction and characteristics of a microscale long-optical-path electrochemi- cal cell with a plug-in thin-layer electrode are described.Using ferricyanide as the test species,the thermodynamic parameters of el...The construction and characteristics of a microscale long-optical-path electrochemi- cal cell with a plug-in thin-layer electrode are described.Using ferricyanide as the test species,the thermodynamic parameters of electron transfer processes are determined at car- bon,plantinum,and gold electrodes.展开更多
Quantitative thickness estimation of thin-layer is a great challenge in seismic exploration, especially for thin-layer below tuning thickness. In this article, we analyzed the seismic response cha- racteristics of rhy...Quantitative thickness estimation of thin-layer is a great challenge in seismic exploration, especially for thin-layer below tuning thickness. In this article, we analyzed the seismic response cha- racteristics of rhythm and gradual type of thin-layer wedge models and presented a new method for thin-layer thickness estimation which uses relative peak frequency increment. This method can de- scribe the peak frequency to thickness relationship of rhythm and gradual thin-layers in unified equa- tion while the traditional methods using amplitude information cannot. What's more, it won't be in- fluenced by the absolute value of thin-layer reflection coefficient and peak frequency of wavelet. The unified equations were presented which can be used for rhythm and gradual thin-layer thickness cal- culation. Model tests showed that the method we introduced has a high precision and it doesn't need to determine the value of top or bottom reflection coefficient, so it has a more wide application in practice. The application of real data demonstrated that the relative peak frequency increment attribute can character the plane distribution feature and thickness characteristic of channel sand bodies very well.展开更多
基金Supported by Enhancement Project of Basic Scientific Research Ability of Young and Middle-aged Teachers in Guangxi Universities(2020KY07040)School-level Scientific Research Project of Guangxi University of Chinese Medicine(2024QN022)Self-financed Scientific Research Project of Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine(GXZYL20240818).
文摘[Objectives]To explore the methods for identifying pure honey.[Methods]Using 35 batches of Jiulongteng honey sourced from various production areas in Guangxi as the research subjects,this study investigated the chromogenic reactions of starch and dextrin,as well as the comparative study of thin-layer chromatography of oligosaccharides present in Jiulongteng honey.[Results]None of the 35 batches of Jiulongteng honey samples exhibited blue(indicating starch),green,or reddish-brown(indicating dextrin)coloration,suggesting that no adulterants such as artificially added starch,dextrin,or sugar were present in these samples.Furthermore,none of the 35 batches displayed additional spots below the corresponding positions of the control,indicating that the sugar composition was consistent with the oligosaccharide profile of natural honey.No components inconsistent with the oligosaccharide profile of natural honey were detected.Therefore,it can be concluded that the Jiulongteng honey samples in this experiment were pure and free from adulteration with starch,dextrin,or other sugar substances.[Conclusions]The method employed in this experiment is straightforward and quick to implement,effectively preventing adulterated honey from entering the market.It enhances the efficiency of quality control for Jiulongteng honey and promotes the healthy development of the Jiulongteng honey industry.
基金National Key R&D Program of China(Nos.2019YFC1711000 and 2018YFC1707900)the National Natural Science Foundation of China(No.8200140730)Qi-Huang Scholar of National Traditional Chinese Medicine Leading Talents Support Program(2018)。
文摘In this study,a high performance thin-layer chromatography/single quadrupole mass spectrometry QDa(HPTLC-QDa)method for robust authentication of Ganoderma lucidum,a popular and valuable herbal medicine,has been developed.This method is simple and practical,which allows direct generation of characteristic mass spectra from the HPTLC plates automatically with the application of in situ solvent desorption interface.The HPTLC silica gel plates were developed with toluene-ethyl formate-formic acid(5:5:0.2,V/V)and all bands were transferred to QDa system directly in situ using 80%methanol with 0.1%formic acid as desorption solvent.The acquired HPTLC-QDa spectra showed that luminous yellow band b3,containing ganoderic acid B/G/H and ganodeneric acid B,the major active components of Ganoderma,could be found only in G.lucidum and G.lucidum(Antler-shaped),but not in G.sinense and G.applanatum.Moreover,bands b13 and b14 with m/z 475/477 and m/z 475/491/495,respectively,could be detected in G.lucidum(Antler-shaped),but not in G.lucidum,thus allowing simple and robust authentication of G.lucidum with confused species.This method is proved to be simple,practical and reproducible,which can be extended to analyze other herbal medicines.
基金National Key Research and Development Program of China(Grant No.2018YFC1707300)。
文摘The holistic characterization and quality control of all the medicinal herbs of proprietary Chinese medicines(PCMs)are of great significance to ensure their safety,efficacy,and consistency.Thin-layer chromatography(TLC),a simple and classic approach for qualitatively characterizing and examining quality markers of natural products,has been widely used in the characterization and quality control of traditional Chinese medicines.Zaoren Anshen(ZRAS)capsule,prepared from three medicinal herbs of fried Ziziphi Spinosae Semen,Salvia Miltiorrhiza Radix et Rhizoma,and vinegar-processed Schisandrae Chinensis Fructus,is a famous PCM in China for the treatment of insomnia,amnesia,and dizziness in clinical practice.However,no effective method is available so far for simultaneous identification and examination of all the three medicinal herbs of ZRAS capsule.In the present study,we developed a TLC method via twice-development and visualization by UV light or chromogenic agent,which could be used for simultaneous qualitative identification of all the three medicinal herbs of ZRAS capsule in one plate.Moreover,the sample preparation method was optimized.The developed TLC method was rapid,simple,low-cost,and effective,and thus it could be used for quality control of ZRAS capsule.
文摘Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids.
基金Supported by National Key Technology Research and Development Program(2015BAC05B02)Fundamental Research Funds for the Central Universities(2018NZD10)
文摘[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L. franchetii from different localities were determined according to the methods described in Chinese Pharmacopoeia( 2015 Edition). [Results] In the 10 samples,the contents of moisture were all less than or equal to 15. 0%; the contents of total ash were all below 12. 0%; and the contents of acid-insoluble ash were all less than 3. 0%. The contents of water-soluble extract( by cold-soaked extraction method) in the samples were all below 12. 0% except those from Hongyuan Prairie of Sichuan Province and Xinglong Mountain in Lanzhou City,Gansu Province. [Conclusions]The contents of the four indicators measured in this experiment varied by small margins,indicating that the quality was relatively stable. This study provides theoretical data for the revision of the quality standards for L. franchetii.
文摘A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity.
文摘ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused. The solvent System was petroleum ether-ethyl acetate-glacial acetic acid (8o:20:1) and the spra-ying reagent was a solution of sulphuric acid and vanillin. Under the selected con-ditions, the peak area was linearly related to the cholesterol amount for the range between 80~700 ng per spot. The intraplate and interplate coefficients were 2.4% and 7.4% respectively. The recovery of cholesterol was 101.6%. The method presented was simple, rapid and accurate. The results of experi-mental investigation and clinical application were satisfactory.
基金the Research Committee of The Hong Kong Polytechnic University(No.G-V877)the Area of Excellence(AoE)of"Chinese Medicine Research and Further Development"of the University Grant Council(UGC)of Hong Kong Special Administrative Region(No.AoE/B-10/01)
文摘Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine. Since the isocratic elution method cannot be applied successfully in TLC analysis for separating all the nucleoside components, the stepwise gradient elution has been developed in this work to separate eight nucleoside standards with success. In this way, quantitative analyses of the samples of Cordyceps sinensis were achieved via the pro-posed TLC procedure coupled with the scanning densitometric techniques of CAMAG and TLCQA methods for qualitative and quantitative analysis.
基金supported by the National Key Research and Development Program of China(No.2018YFC1707904,2018YFC1707900)。
文摘Objective:Belamcandae Rhizoma and Iridis Tectori Rhizoma are easily confused with each other.The main objective of this study is to distinguish them using chemical analysis.Materials and Methods:Thin-layer chromatography(TLC)and high-performance liquid chromatography(HPLC)fingerprint methods were established to compare the chemical profile,while HPLC quantitation was used to determine the contents of three isoflavones in thirty batches of Belamcandae Rhizoma and Iridis Tectori Rhizoma samples.Results:The two herbs could be distinguished by TLC using acetic acid-n hexane-ethyl acetate(1:90:80 v/v/v)as the mobile phase,according to the fluorescent band under 366 nm at R_(f) 0.2.In total,12 compounds were identified in the 24-min HPLC fingerprint.The similarity coefficient between the two herbs was 0.54±0.01.Mangiferin(1),tectoridin(2),iridin(3),irigenin(5),irisflorentin(6),and iristectorin A(9)were the main peaks in Belamcandae Rhizoma,while tectoridin(2)and tectorigenin(4)were the major peaks in Iridis Tectori Rhizoma.The contents of 2 in Iridis Tectori Rhizoma(2.50±0.20%)were 8.93 times higher than that of Belamcandae Rhizoma(0.28±0.08%),while the ones of 5 and 6 were slightly lower in Iridis Tectori Rhizoma.Conclusions:The study established fast and effective methods to distinguish Belamcandae Rhizoma from Iridis Tectori Rhizoma.
文摘A specific, precise and stability indicating high-performance thin-layer chromatographic method for simultaneous estimation of pantoprazole sodium and itopride hydrochloride in pharmaceutical formulations was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60F254 as the stationary phase. The solvent system consisted of methanol:water:ammonium acetate; 4.0:1.0:0.5 (v/v/v). This system was found to give compact and dense spots for both itopride hydrochloride (Rf value of 0.55__+0.02) and pantoprazole sodium (Rf value of 0.85+0.04). Densitometric analysis of both drugs was carried out in the reflectance- absorbance mode at 289 nm. The linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9988___0.0012 in the concentration range of 100--400 ng for pantoprazole sodium. Also, the linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9990_+0.0008 in the concentration range of 200-1200 ng for itopride hydrochloride. The method was validated for specificity, precision, robustness and recovery. Statistical analysis proves that the method is repeatable and selective for the estimation of both the said drugs. As the method could effectively separate the drug from its degradation products, it can be employed as a stability indicating method.
文摘A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer chromatograpic scanner in zig-zag dual-wavelength reflection mode.Detection sensitivity for strychniue was about 0. 05 μg. Quantification recoveries were between89. 2% and 99. 5% with RSD between 2. 92% and 13. 21 %. The method was applied to investigate thedistribution or strychnine in intoxicated rats. The results showed that there were remarkable difference in organs or tissues with the aigaest concentration 4. 56±1. 41μg/g in liver. Diversification experiment proves the method also could be used to analyze other alkaloids in biological samples if theconditions slightly modified.
文摘Silica gel thin-layer plates covered with L-arginine and copper acetate were used for the separation of amino acid enantiomers, The chromatographic selectivity and the effects of plate different preparation methods, sample molecular structure and solvent compositions on resolution performance were also discussed.
基金financially supported by the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(Grant Nos.CUGGC09 and CUG200637)Opening Fund of Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education(Grant No.19CX05005A-201)the Sinopec Science and Technology Department(Grant Nos.P2006 and 33550000-21-ZC0611-0006)。
文摘Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recently,more and more thin-layer super-heavy oil reservoirs have been discovered in China,while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply,so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil.To this end,this paper focuses on the enlightenment of field application in SAGD technology.Firstly,based on typical SAGD field projects,the development history of SAGD technology in the world was reviewed,and the influence of reservoir physical properties on the application of SAGD technology in thin-layer superheavy oil reservoirs was analyzed.Secondly,the well pattern,wellbore structure,pre-heating,artificial lift,and monitor technique of SAGD were detailed described,and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs.Lastly,the gas-and solventassistant SAGD were comprehensively evaluated,and their application potential in thin-layer superheavy oil reservoirs was studied.The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.
基金Supported by the National Nature Science Foundation of China (50930006) Acknowledgment The authors thank Shenzhen Water Group Co., Ltd. (China) for their support for this project and also Si Yaohui, Ph.D., for his assistance.
文摘Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism bears great meaning for its development and utilization. The effects of temperature and microwave cracking in municipal sewage sludge drying characteristics are stud- ied through municipal sewage sludge drying experiment. Experiments shows that higher drying temperature would lead to a more acutely changing drying rate (DR). The DR had increased from 0.005 g/(g.min) to 0.060 g/(g·min), which was 12 times enlarged, while the temperature rose from 70℃ to 160 ℃. The higher the temperature was, the earlier the peak value of DR appeared. The experiments indicated that the temperature was the decisive factor affecting the DR. The microwave-induced sludge reached the highest DR at the moisture rate (MR) of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the DR was rising in proportion to the microwave radiation dose. The diffusion coefficient had been calculated according to Fick's law. In com- parison to that of the original one, the diffusion coefficient of microwave-induced sludge was obviously enlarged more than two times. By fit examinations, Model Weibull was proven to be the most fit one for thermal thin-layer drying of municipal sludge. By means of Arrhenius equation, the obtained average activation energy of municipal sludge was 37.1 kJ/(mol·K).
文摘Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids.
基金Supported by the National Natural Science Foundation of China(42172177)CNPC Scientific Research and Technological Development Project(2021DJ05)PetroChina-Southwest University of Petroleum Innovation Consortium Project(2020CX020000).
文摘Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin.
基金supported by the National Science and Technology Pillar Program(No.2012BAC04B02)the National Natural Science Fund of China(No.51408243)+3 种基金the Natural Science Foundation of Fujian Province of China(No.2015J01213)the Fundamental Research Funds for Central Universities(No.11QZR07)the Science and Technology Plan Fund of Quanzhou City(No.2014Z218)the Research Funds of Huaqiao University(No.14BS216)
文摘Bioreactive thin-layer capping(BTC)with biozeolite provides a potential remediation design that can sustainably treat N contamination from sediment and overlying water in eutrophic water bodies.Nitrogen(N)reduction using BTC with biozeolite was examined in a field incubation experiment in a eutrophic river in Yangzhou,Jiangsu Province,China.The biozeolite was zeolite with attached bacteria,including two isolated heterotrophic nitrifiers(Bacillus spp.)and two isolated aerobic denitrifiers(Acinetobacter spp.).The results showed that the total nitrogen(TN)reduction efficiency of the overlying water by BTC with biozeolite(with thickness of about 2 mm)reached a maximum(56.69%)at day 34,and simultaneous heterotrophic nitrification and aerobic denitrification occurred in the BTC system until day 34.There was a significant difference in the TN concentrations of the overlying water between biozeolite capping and control(t-test;p〈0.05).The biozeolite had very strong in situ bioregeneration ability.Carbon was the main source of nitrifier growth.However,both dissolved oxygen(DO)and carbon concentrations affected denitrifier growth.In particular,DO concentrations greater than 3 mg/L inhibited denitrifier growth.Therefore,BTC with biozeolite was found to be a feasible technique to reduce N in a eutrophic river.However,it is necessary to further strengthen the adaptability of aerobic denitrifiers through changing domestication methods or conditions.
文摘The construction and characteristics of a microscale long-optical-path electrochemi- cal cell with a plug-in thin-layer electrode are described.Using ferricyanide as the test species,the thermodynamic parameters of electron transfer processes are determined at car- bon,plantinum,and gold electrodes.
基金supported by the Fundamental Research Funds for the Central Universities,Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20110022120004)China National Key S&T Project on Marine Carbonate Reservoir Characterization(No.2011ZX05004003)
文摘Quantitative thickness estimation of thin-layer is a great challenge in seismic exploration, especially for thin-layer below tuning thickness. In this article, we analyzed the seismic response cha- racteristics of rhythm and gradual type of thin-layer wedge models and presented a new method for thin-layer thickness estimation which uses relative peak frequency increment. This method can de- scribe the peak frequency to thickness relationship of rhythm and gradual thin-layers in unified equa- tion while the traditional methods using amplitude information cannot. What's more, it won't be in- fluenced by the absolute value of thin-layer reflection coefficient and peak frequency of wavelet. The unified equations were presented which can be used for rhythm and gradual thin-layer thickness cal- culation. Model tests showed that the method we introduced has a high precision and it doesn't need to determine the value of top or bottom reflection coefficient, so it has a more wide application in practice. The application of real data demonstrated that the relative peak frequency increment attribute can character the plane distribution feature and thickness characteristic of channel sand bodies very well.