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]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
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
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
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ...In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.展开更多
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m...In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing.展开更多
Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision...Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training.展开更多
The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environmen...The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation.展开更多
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t...Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates.展开更多
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema...At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater.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
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
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
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
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
The current study is designed to evaluate certain immunocytochemical(ICC)biomarkers to gain a better cytodiagnosis.For this purpose,85 patients from March 2016 to March 2019 who planned to get a hysteroscopy assay wer...The current study is designed to evaluate certain immunocytochemical(ICC)biomarkers to gain a better cytodiagnosis.For this purpose,85 patients from March 2016 to March 2019 who planned to get a hysteroscopy assay were recruited.Cytological sampling was conducted by scratching the uterus cavity using SAP-1,and the samples were processed as liquid-based smears,using SurePath technology.36 patients diagnosed with EC or atypical endometrial hyperplasia were recruited in this study.33 cases were diagnosed with EC,and 3 cases were diagnosed with atypical endometrial hyperplasia,allocated with EC or precancerous lesions group.26 cases were diagnosed with benign lesions group.Among these cases,9 cases were diagnosed with endometrial simple hyperplasia,2 cases were diagnosed with complicated hyperplasia,5 cases were diagnosed with an irregular proliferation of endometrium and 10 cases were diagnosed with endometrial polyps.There were 23 cases in the healthy group.Staining in thin-layer endometrial preparations by ICC and using H-score or counting the percentage of stained cells.The presentation of PTEN in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 50(Youden’s index:0.698)PTEN expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 83.7%and 86.1%.The presentation of Ki-67 in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 15%(Youden’s index:0.76)Ki-67 expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 94.4%and 81.6%.In this study,the use of different cut-off values for Ki-67 and PTEN helped differentiate endometrial lesions.Immunocytochemistry in the ECT detection of PTEN and Ki-67 can improve the diagnostic capabilities of endometrial cancer and precancerous lesions.展开更多
The integration of the photocatalytic effect into solar steam is highly desirable for addressing freshwater shortages and water pollution.Here,a ternary film structure for the adsorption and photothermal and photocata...The integration of the photocatalytic effect into solar steam is highly desirable for addressing freshwater shortages and water pollution.Here,a ternary film structure for the adsorption and photothermal and photocatalytic treatment of wastewater was designed by combining the technique of self-assembled carbon nano paper with a nitrogen composite titanium dioxide(N-TiO_(2))deposited on the surface of carbon nanotubes(CNT)using polyvinylidene fluoride(PVDF)as a substrate.The photogeneration of reactive oxygen species can be promoted by rapid oxygen diffusion at the three-phase interface,whereas the interfacial photothermal effect promotes subsequent free radical reactions for the degradation of rhodamine B(93%).The freshwater evaporation rate is 1.35 kg·m^(-2)·h^(-1)and the solar-to-water evaporation efficiency is 94%.Importantly,the N-TiO_(2)/CNT/PVDF(N-TCP)film not only effectively resists mechanical damage from the environment and maintains structural integrity,but can also be made into a large film for outdoor experiments in a large solar energy conversion device to collect fresh water from polluted water and degrade organic dyes in source water simultaneously,opening the way for applications in energy conversion and storage.展开更多
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 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.
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.
基金Supported in part by Natural Science Foundation of Guangxi(2023GXNSFAA026246)in part by the Central Government's Guide to Local Science and Technology Development Fund(GuikeZY23055044)in part by the National Natural Science Foundation of China(62363003)。
文摘In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.
基金supported by Anhui Provincial Natural Science Foundation(2408085QA030)Natural Science Research Project of Anhui Educational Committee,China(2022AH050825)+3 种基金Medical Special Cultivation Project of Anhui University of Science and Technology(YZ2023H2C008)the Excellent Research and Innovation Team of Anhui Province,China(2022AH010052)the Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology,China(2021yjrc51)Collaborative Innovation Program of Hefei Science Center,CAS,China(2019HSC-CIP006).
文摘In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing.
基金funded by the Beijing Engineering Research Center of Electric Rail Transportation.
文摘Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training.
基金supported by the National Key Research and Develop-ment Program(No.2022YFC3701103)the National Natural Science Foundation of China(Nos.42130714 and 41931287).
文摘The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation.
基金Supported by the National Natural Science Foundation of China under Grant No.51975138the High-Tech Ship Scientific Research Project from the Ministry of Industry and Information Technology under Grant No.CJ05N20the National Defense Basic Research Project under Grant No.JCKY2023604C006.
文摘Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates.
基金supported by the National Natural Science Foundation of China(Project No.42307555).
文摘At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater.
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）.
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.
基金supported by Beijing Municipal Administration of Hospitals Incubating Program,Code:PX2018039Beijing Talents Foundation Youth backbone individual programBeijing Tsinghua Changgung Hospital Fund(Grant No.120151003)。
文摘The current study is designed to evaluate certain immunocytochemical(ICC)biomarkers to gain a better cytodiagnosis.For this purpose,85 patients from March 2016 to March 2019 who planned to get a hysteroscopy assay were recruited.Cytological sampling was conducted by scratching the uterus cavity using SAP-1,and the samples were processed as liquid-based smears,using SurePath technology.36 patients diagnosed with EC or atypical endometrial hyperplasia were recruited in this study.33 cases were diagnosed with EC,and 3 cases were diagnosed with atypical endometrial hyperplasia,allocated with EC or precancerous lesions group.26 cases were diagnosed with benign lesions group.Among these cases,9 cases were diagnosed with endometrial simple hyperplasia,2 cases were diagnosed with complicated hyperplasia,5 cases were diagnosed with an irregular proliferation of endometrium and 10 cases were diagnosed with endometrial polyps.There were 23 cases in the healthy group.Staining in thin-layer endometrial preparations by ICC and using H-score or counting the percentage of stained cells.The presentation of PTEN in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 50(Youden’s index:0.698)PTEN expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 83.7%and 86.1%.The presentation of Ki-67 in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 15%(Youden’s index:0.76)Ki-67 expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 94.4%and 81.6%.In this study,the use of different cut-off values for Ki-67 and PTEN helped differentiate endometrial lesions.Immunocytochemistry in the ECT detection of PTEN and Ki-67 can improve the diagnostic capabilities of endometrial cancer and precancerous lesions.
基金Scientific Research Fund of Zhejiang Provincial Education Department(Y202250501)SRT Research Project of Jiaxing Nanhu University。
文摘The integration of the photocatalytic effect into solar steam is highly desirable for addressing freshwater shortages and water pollution.Here,a ternary film structure for the adsorption and photothermal and photocatalytic treatment of wastewater was designed by combining the technique of self-assembled carbon nano paper with a nitrogen composite titanium dioxide(N-TiO_(2))deposited on the surface of carbon nanotubes(CNT)using polyvinylidene fluoride(PVDF)as a substrate.The photogeneration of reactive oxygen species can be promoted by rapid oxygen diffusion at the three-phase interface,whereas the interfacial photothermal effect promotes subsequent free radical reactions for the degradation of rhodamine B(93%).The freshwater evaporation rate is 1.35 kg·m^(-2)·h^(-1)and the solar-to-water evaporation efficiency is 94%.Importantly,the N-TiO_(2)/CNT/PVDF(N-TCP)film not only effectively resists mechanical damage from the environment and maintains structural integrity,but can also be made into a large film for outdoor experiments in a large solar energy conversion device to collect fresh water from polluted water and degrade organic dyes in source water simultaneously,opening the way for applications in energy conversion and storage.
