A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. An...A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. And a set of pressure controlling devices with PLC as a central processor are designed. It can be got from the relevant experiments that the pressure-stroke characteristic is correct and its control for forming process is available.展开更多
Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant ...Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant properties of the bonding zone metal are improved, and the joints’ strengths at high temperature is increased. The joints’ shear strength at room temperature and at 600 ℃ reach 126~133 MPa and 32~34 MPa, respectively, with suitable bonding pressure. The reaction between aluminum and Si 3N 4 ceramics, which produces Al Si N O type compounds is the dominant interfacial reaction, while the reactions between the second active element Ti or Zr in the aluminum based alloys and Si 3N 4 ceramics also occur to some extend. [展开更多
The expressions of the radius and the surface tension of surface of tension Rs and γs in terms of the pressure distribution for nanoscale liquid threads are of great importance for molecular dynamics (MD) simulatio...The expressions of the radius and the surface tension of surface of tension Rs and γs in terms of the pressure distribution for nanoscale liquid threads are of great importance for molecular dynamics (MD) simulations of the interfacial phenomena of nanoscale fluids; these two basic expressions are derived in this paper. Although these expressions were derived first in the literature[Kim B G, Lee J S, Han M H, and Park S, 2006 Nanoscale and Microscale Thermophysical Engineering, 10, 283] and used widely thereafter, the derivation is wrong both in logical structure and physical thought. In view of the importance of these basic expressions, the logic and physical mistakes appearing in that derivation are pointed out.展开更多
We report a molecular dynamics study of structural and transport properties of liquid nickel under high pres- sures. Pressure dependencies of pair distribution function and pair correlation entropy along the melting l...We report a molecular dynamics study of structural and transport properties of liquid nickel under high pres- sures. Pressure dependencies of pair distribution function and pair correlation entropy along the melting line indicate that the configuration change along melting lines decreases with increasing pressure. The calculated diffusion coefficients and viscosity by using entropy-scaling laws with modified parameters and ideal parameters are compared with those extracted from mean-square displacement or the Stokes-Einstein relation. The results suggest that the entropy-scaling laws hold well for coefficients and viscosity increase moderately with liquid nickel under high-pressure conditions, and the diffusion pressure along melting lines.展开更多
The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 μg. Results show bioaccumulation factor of pestic...The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 μg. Results show bioaccumulation factor of pesticide “Raid?” in lipid, up to three times that of the feed at the first concentration and gradually decreased as the concentration increased in the muscle > (0.7), brain > (0.5) and liver > (0.3) as indicated in the text. At higher concentration of 961 μg/g, bioaccumulation factor decreased in the lipid to 1.2 and 0.6 in the muscle, 0.03 in the brain and 0.08 in the liver respectively. High Pressure Liquid Chromatography (HPLC) analysis of raid extract suggests the presence of micprothrin and palethrin. The implications are numerous, but simply put that accidental ingestion of chlorinated hydrocarbon as in “Raid?” may involve convulsions, collapse and coma after only brief excitation and ataxia at the onset.展开更多
The influence of stress and strain on the solid/liquid segregation formed in deformed semisolid metal was studied.Thecompression experiment at a low constant strain rate was conducted on a Gleeble 1500 thermo-mechanic...The influence of stress and strain on the solid/liquid segregation formed in deformed semisolid metal was studied.Thecompression experiment at a low constant strain rate was conducted on a Gleeble 1500 thermo-mechanical sireulator.The stress and strain fields of the samples were calculated by finite element method.The experiment results and themodeling results prove that the hydrostatic pressure gradient is the driving force for solid/liquid segregation.Thesegregated liquid phase usually agglomerates in the micropores and shear bands are created by sliding of equiaxeddendrite grains.The sliding among the grains is influenced by the solid fraction and grain size of the semisolid slurry,so as the solid fraction and grain size change,the morphology of the segregated liquid changes.展开更多
Beijing Aerospace System Engineering Institute of China Academy of Launch Vehicle Technology (CALT) declared recently that theinstitute has set up a laboratory whichwould operate a newly
In the industrial field,tailored blank forming with aluminum alloy(Al-alloy)has developed fast to meet the demands for large size integrated components with curved surfaces of high precision and with uniform mechanica...In the industrial field,tailored blank forming with aluminum alloy(Al-alloy)has developed fast to meet the demands for large size integrated components with curved surfaces of high precision and with uniform mechanical properties.Traditional forming methods for tailored blank components faced challenges with uneven deformation behaviors and coexistence of rupture and wrinkling defects occuring during the forming process.In this paper,a new manufacturing procedure is proposed with advanced welding and forming technologies for forming integrated shell components.Friction stir welding with post-weld heat treatment was employed to prepare the tailor welded blank and improve its formability prior to forming.A double-sided pressure sheet hydroforming process was introduced to fabricate the Al-alloy tailored blank into a curved surface shell.Finite element modeling was established to analyze the effect of the weld line position and loading paths of stress distributions during the double-sided sheet hydroforming(DSHF)process.A large double-action CNC sheet hydroforming press with tonnage of 150 MN and high pressure liquid volume of 5 m~3 was developed in China.As an application case of the proposed process and equipment,a full-scale tank dome with a diameter of 3 m was successfully hydroformed with a large size Al-alloy tailored blank.It was shown that the DSHF process has the advantages in controlling rupture and wrinkling defects with an Al-alloy tailored blank,and the novel manufacturing procedure enables the production of integrated thin-walled component more competitively than traditional methods.展开更多
A reverse-phase high pressure liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for the quantitative analysis of hupehenine in the total alkaloids from Friti...A reverse-phase high pressure liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for the quantitative analysis of hupehenine in the total alkaloids from Fritillaria hupehensis. Samples were analyzed on a reverse-phase column (Hypersil C-18) with a mobile phase of methanol:water:chloroform: triethylamine (85:15:1:0.6). The ELSD was set at the drift tube temperature of 68.3℃ and gas flow rate of 1.8 L/min. Hupehenine's retention time was 13.7 min with an asymmetry factor of 1.2. The validity of the method has been verified with linearity, limit of detection, accuracy and precision. The logarithmic linear curve was obtained from 8.936 to 134.04 μg/mL (r=0.9993). The detection limit (S/N〉3) of hupehenine was 1.79 μg/mL on the column. Intra-day RSD was 1.42% and inter-day RSD was 2.26% (3 days within a week). The average recovery of hupehenine was 101.50%, and RSD was 1.62%.展开更多
The effects of the secondary gradient crystallizing pressure, temperature and time on the purity and crystallization ratio of andrographolide were investigated via single factor experiments. The shape of crystal was...The effects of the secondary gradient crystallizing pressure, temperature and time on the purity and crystallization ratio of andrographolide were investigated via single factor experiments. The shape of crystal was observed with scanning electron microscopy (SEM). The purity of andrographolide was determined by high pressure liquid chromatography (HPLC). It was found that the optimized parameters were pressure 14 MPa, temperature 55℃, time 60 min, and CO2 flow rate 15 L min-1, under these conditions the particle of andrographolide was much smaller, the crystal of andrographolide was distributed in floccule on crystal board,with the purity of andrographolide 92.5%, the crystallization ratio 48.9%.展开更多
The relationship between the vapor pressure of liquid copper and the flow rate of carrier gas argon was discussed, when the carrier gas method was used to determine the vapor pressure of liquid copper at 1892 K. The p...The relationship between the vapor pressure of liquid copper and the flow rate of carrier gas argon was discussed, when the carrier gas method was used to determine the vapor pressure of liquid copper at 1892 K. The proper argon flow rate range obtained was 150-500 mL/min and enough evidence was provided to verify the vapor pressure-flow rate of carrier gas relationship at the target temperature. Based on the proper flow rate range, the vapor pressure of liquid copper was measured at 1609-1892 K. The relationship of vapor pressure-temperature obtained by the method of regression analysis can be expressed as: In(p/Pa) = (25.470 -I- 0.903) - (39099.8 -4- 1574.5)/T, Further, the thermodynamic properties including the heat of vaporization and the Gibbs free energy of the Cu (I) = Cu (g) reaction were calculated by the vapor pressiJre obtained over the temperature range covered.展开更多
To investigate the exon mutation of vitamin K-dependent gamma-glutamyl carboxylase (GGCX or VKDC) in patients with calcium oxalate urolithasis, renal cortex and peripheral blood samples were obtained from severe hyd...To investigate the exon mutation of vitamin K-dependent gamma-glutamyl carboxylase (GGCX or VKDC) in patients with calcium oxalate urolithasis, renal cortex and peripheral blood samples were obtained from severe hydronephrosis patients (with or without calculi), and renal tumor patients undergoing nephrectomy. GGCX mutations in all 15 exons were examined in 44 patients with calcium oxalate urolithiasis (COU) by polymerase chain reaction (PCR) and denatured high pressure liquid chromatography (DHPLC), and confirmed by sequencing. Mutation was not found in all COU samples compared to the controls. These data demonstrated that functional GGCX mutations in all 15 exons do not occur in most COU patients. It was suggested that there may be no significant association between the low activity and mutation of GGCX in COU.展开更多
Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active c...Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active compound contained in P. amurense. Our objective in this study was to quantify the content of berberine in P.amurense from sites at different elevations on Changbai Mountain. We collected samples of P. amurense from five different elevations on Changbai Mountain. Berberine in samples was extracted by ultrahigh pressure extraction(UPE). And the quantity was measured by high performance liquid chromatography(HPLC). First, the optimal HPLC conditions for berberine were identified with satisfactory precision(relative standard deviation, R SD/5.6 %), good accuracy(relative error, R E/ 3.6 %) and good linear relation(R2= 0.9998) in the range of 6.576–328.8 mg L-1. Second, the combination of UPE and HPLC methods in quantitative analysis of berberine showed high repeatability(R SD= 3.28 %), reproducibility(R SD= 4.72 %),stability(R SD/ 1.27 %) and good recovery(99.54 %) for real plant materials. Samples from Heilongjiang Province at the lowest elevation contained the highest amount of berberine.Similarly, the lowest amount of berberine was recorded in samples from Changbai Forest Bureau of Jilin Province collected at the highest elevation in this paper. The proposed UPE–HPLC method is simple, reliable and low-cost for quantitative analysis of berberine. Content of berberine in P.amurense varied significantly by site on Changbai Mountain.展开更多
We review recent progress in studying silicate, carbonate, and metallic liquids of geological and geophysical importance at high pressure and temperature, using the large-volume high-pressure devices at the third-gene...We review recent progress in studying silicate, carbonate, and metallic liquids of geological and geophysical importance at high pressure and temperature, using the large-volume high-pressure devices at the third-generation synchrotron facility of the Advanced Photon Source, Argonne National Laboratory. These integrated high-pressure facilities now offer a unique combination of experimental techniques that allow researchers to investigate structure, density, elasticity, viscosity, and interfacial tension of geo-liquids under high pressure, in a coordinated and systematic fashion. Experimental techniques are described, along with scientific highlights. Future developments are also discussed.展开更多
This paper introduces a 100 MPa water gas twophase fluid pressurization device.The device can provide 100 MPa gas pressure and 200 MPa liquid pressure for small volume(<20 mL)high-pressure experimental devices.This...This paper introduces a 100 MPa water gas twophase fluid pressurization device.The device can provide 100 MPa gas pressure and 200 MPa liquid pressure for small volume(<20 mL)high-pressure experimental devices.This device can make the pressure control independent of the temperature control without changing the material components of the system.The resolution of this device in adjusting the pressure is±0.2 MPa in the process of boosting and depressurizing.This pressure boosting device generates very little vibration during work and it can be used in experiments with strict requirements on vibration.As a thermodynamic parameter,pressure has a great influence on matter.In the field of experimental geochemistry,pressure is not only an experimental method and an extreme condition but an important physical parameter independent of temperature and chemical composition.展开更多
An apparatus for measuring solubilities of gases in liquids at elevated temperatures and pressures has been constructed. Using this apparatus, the slubilities of N_2 and CO_2 in some solvents have been determined in t...An apparatus for measuring solubilities of gases in liquids at elevated temperatures and pressures has been constructed. Using this apparatus, the slubilities of N_2 and CO_2 in some solvents have been determined in the temperature range between 20 and 230℃, and at pressures up to 130 atm. The experimental results obtained generally agree well with literature values. It is shown that this apparatus is reliable; attainment of equilibria needs only about 5 hours; precision of the measure- ments is ±0.2%.展开更多
A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce ...A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.展开更多
Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas sp.An experimental design is employed to determine the effect of th...Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas sp.An experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC tests.All the extracts show significant antioxidant activity in all assays.Besides,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.展开更多
OBJECTIVE:To investigate the relationship between the cardiotonic activity of Fuzi(Radix Aconiti Lateralis Preparata,RALP)and its fingerprint determined by liquid chromatography-mass spectrometry(LC-MS).METHODS:First,...OBJECTIVE:To investigate the relationship between the cardiotonic activity of Fuzi(Radix Aconiti Lateralis Preparata,RALP)and its fingerprint determined by liquid chromatography-mass spectrometry(LC-MS).METHODS:First,the fingerprints of six processed products of RALP were established by high performance liquid chromatography quadrupole time-of-flight mass spectrometry(HPLC-Q-TOF-MS)followed by analysis of the principal component of the relative peak area of its common peaks.Next,the scores of the first five principal components were used as input for an artificial neural network(ANN).Additionally,the therapeutic effect of RALP was assessed by measuring the hemodynamic indexes of heart failure model rats.Subsequently,fluorescence semi-quantitative polymerase chain reaction and an enzyme-linked immunosorbent assay kit were used to determine the effects of RALP-processed products on the serum levels of noradrenaline(NA),angiotensin-Ⅰ(Ang-Ⅰ),and the expression ofβ-norepinephrine receptor m RNA(β-NRm)in the rat cardiac tissues.P<0.05 was used as the output of the ANN.Finally,a network was constructed to display the relationship between the LC-MS fingerprints and the cardiotonic activity of the RALP-processed products.RESULTS:Several types of RALPs can improve diastolic function,systolic function and heart rate.On the basis of the findings from the principal component analysis(PCA)of 16 common peaks of fingerprints of six RALP-processed products,it was revealed that the first five principal components may include 100%of the information of the original data.As observed from the multilayer perceptron neural network analysis,principal component 4 presented with the strongest effects on serum levels of NA and Ang-Ⅰin rats,while principal component1 exerted the greatest effect onβ-NRm expression in cardiac tissue.CONCLUSION:The key findings obtained from this study indicated that the network constructed by the PCA-ANN may predict pharmacodynamic effects of the main ingredients of Traditional Chinese Medicine(TCM).This method may serve as a new approach to identify the relationship between LC-MS fingerprints and the pharmacodynamic effects of TCM ingredients.展开更多
基金This project is supported by Provincial Natural ScienceFoundation of Shanxi. Selected form Proceedings of 2000the First Inte
文摘A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. And a set of pressure controlling devices with PLC as a central processor are designed. It can be got from the relevant experiments that the pressure-stroke characteristic is correct and its control for forming process is available.
文摘Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant properties of the bonding zone metal are improved, and the joints’ strengths at high temperature is increased. The joints’ shear strength at room temperature and at 600 ℃ reach 126~133 MPa and 32~34 MPa, respectively, with suitable bonding pressure. The reaction between aluminum and Si 3N 4 ceramics, which produces Al Si N O type compounds is the dominant interfacial reaction, while the reactions between the second active element Ti or Zr in the aluminum based alloys and Si 3N 4 ceramics also occur to some extend. [
基金RαProject supported by the National Natural Science Foundation of China(Grant No.11072242)the Research and Development Program of Science and Technology of Higher Education of Shanxi Province,China(Grant No.20121029)
文摘The expressions of the radius and the surface tension of surface of tension Rs and γs in terms of the pressure distribution for nanoscale liquid threads are of great importance for molecular dynamics (MD) simulations of the interfacial phenomena of nanoscale fluids; these two basic expressions are derived in this paper. Although these expressions were derived first in the literature[Kim B G, Lee J S, Han M H, and Park S, 2006 Nanoscale and Microscale Thermophysical Engineering, 10, 283] and used widely thereafter, the derivation is wrong both in logical structure and physical thought. In view of the importance of these basic expressions, the logic and physical mistakes appearing in that derivation are pointed out.
基金Supported by the Science and Research Foundation of Sichuan Educational Committee under Grant Nos 13ZB0211 and 13ZA0198the Open Research Fund of Computational Physics Key Laboratory of Sichuan Province under Grant No JSWL2014KF06
文摘We report a molecular dynamics study of structural and transport properties of liquid nickel under high pres- sures. Pressure dependencies of pair distribution function and pair correlation entropy along the melting line indicate that the configuration change along melting lines decreases with increasing pressure. The calculated diffusion coefficients and viscosity by using entropy-scaling laws with modified parameters and ideal parameters are compared with those extracted from mean-square displacement or the Stokes-Einstein relation. The results suggest that the entropy-scaling laws hold well for coefficients and viscosity increase moderately with liquid nickel under high-pressure conditions, and the diffusion pressure along melting lines.
文摘The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 μg. Results show bioaccumulation factor of pesticide “Raid?” in lipid, up to three times that of the feed at the first concentration and gradually decreased as the concentration increased in the muscle > (0.7), brain > (0.5) and liver > (0.3) as indicated in the text. At higher concentration of 961 μg/g, bioaccumulation factor decreased in the lipid to 1.2 and 0.6 in the muscle, 0.03 in the brain and 0.08 in the liver respectively. High Pressure Liquid Chromatography (HPLC) analysis of raid extract suggests the presence of micprothrin and palethrin. The implications are numerous, but simply put that accidental ingestion of chlorinated hydrocarbon as in “Raid?” may involve convulsions, collapse and coma after only brief excitation and ataxia at the onset.
文摘The influence of stress and strain on the solid/liquid segregation formed in deformed semisolid metal was studied.Thecompression experiment at a low constant strain rate was conducted on a Gleeble 1500 thermo-mechanical sireulator.The stress and strain fields of the samples were calculated by finite element method.The experiment results and themodeling results prove that the hydrostatic pressure gradient is the driving force for solid/liquid segregation.Thesegregated liquid phase usually agglomerates in the micropores and shear bands are created by sliding of equiaxeddendrite grains.The sliding among the grains is influenced by the solid fraction and grain size of the semisolid slurry,so as the solid fraction and grain size change,the morphology of the segregated liquid changes.
文摘Beijing Aerospace System Engineering Institute of China Academy of Launch Vehicle Technology (CALT) declared recently that theinstitute has set up a laboratory whichwould operate a newly
基金supported by the Project of National Science Foundation of China(No.U1637209)Project of National Key Research and Development Program(No.2017YFB0306304)
文摘In the industrial field,tailored blank forming with aluminum alloy(Al-alloy)has developed fast to meet the demands for large size integrated components with curved surfaces of high precision and with uniform mechanical properties.Traditional forming methods for tailored blank components faced challenges with uneven deformation behaviors and coexistence of rupture and wrinkling defects occuring during the forming process.In this paper,a new manufacturing procedure is proposed with advanced welding and forming technologies for forming integrated shell components.Friction stir welding with post-weld heat treatment was employed to prepare the tailor welded blank and improve its formability prior to forming.A double-sided pressure sheet hydroforming process was introduced to fabricate the Al-alloy tailored blank into a curved surface shell.Finite element modeling was established to analyze the effect of the weld line position and loading paths of stress distributions during the double-sided sheet hydroforming(DSHF)process.A large double-action CNC sheet hydroforming press with tonnage of 150 MN and high pressure liquid volume of 5 m~3 was developed in China.As an application case of the proposed process and equipment,a full-scale tank dome with a diameter of 3 m was successfully hydroformed with a large size Al-alloy tailored blank.It was shown that the DSHF process has the advantages in controlling rupture and wrinkling defects with an Al-alloy tailored blank,and the novel manufacturing procedure enables the production of integrated thin-walled component more competitively than traditional methods.
基金a grant from the State Ad-ministration of Traditional Chinese Medicine of China (No. D2X004A)
文摘A reverse-phase high pressure liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) has been developed for the quantitative analysis of hupehenine in the total alkaloids from Fritillaria hupehensis. Samples were analyzed on a reverse-phase column (Hypersil C-18) with a mobile phase of methanol:water:chloroform: triethylamine (85:15:1:0.6). The ELSD was set at the drift tube temperature of 68.3℃ and gas flow rate of 1.8 L/min. Hupehenine's retention time was 13.7 min with an asymmetry factor of 1.2. The validity of the method has been verified with linearity, limit of detection, accuracy and precision. The logarithmic linear curve was obtained from 8.936 to 134.04 μg/mL (r=0.9993). The detection limit (S/N〉3) of hupehenine was 1.79 μg/mL on the column. Intra-day RSD was 1.42% and inter-day RSD was 2.26% (3 days within a week). The average recovery of hupehenine was 101.50%, and RSD was 1.62%.
基金financially supported by the National Natura1 Science Foundation of China(29976008)
文摘The effects of the secondary gradient crystallizing pressure, temperature and time on the purity and crystallization ratio of andrographolide were investigated via single factor experiments. The shape of crystal was observed with scanning electron microscopy (SEM). The purity of andrographolide was determined by high pressure liquid chromatography (HPLC). It was found that the optimized parameters were pressure 14 MPa, temperature 55℃, time 60 min, and CO2 flow rate 15 L min-1, under these conditions the particle of andrographolide was much smaller, the crystal of andrographolide was distributed in floccule on crystal board,with the purity of andrographolide 92.5%, the crystallization ratio 48.9%.
基金supported by the Major National S&T Program(No.2011ZX06004-016-002)the Shenyang R&D Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences for support of this work
文摘The relationship between the vapor pressure of liquid copper and the flow rate of carrier gas argon was discussed, when the carrier gas method was used to determine the vapor pressure of liquid copper at 1892 K. The proper argon flow rate range obtained was 150-500 mL/min and enough evidence was provided to verify the vapor pressure-flow rate of carrier gas relationship at the target temperature. Based on the proper flow rate range, the vapor pressure of liquid copper was measured at 1609-1892 K. The relationship of vapor pressure-temperature obtained by the method of regression analysis can be expressed as: In(p/Pa) = (25.470 -I- 0.903) - (39099.8 -4- 1574.5)/T, Further, the thermodynamic properties including the heat of vaporization and the Gibbs free energy of the Cu (I) = Cu (g) reaction were calculated by the vapor pressiJre obtained over the temperature range covered.
文摘To investigate the exon mutation of vitamin K-dependent gamma-glutamyl carboxylase (GGCX or VKDC) in patients with calcium oxalate urolithasis, renal cortex and peripheral blood samples were obtained from severe hydronephrosis patients (with or without calculi), and renal tumor patients undergoing nephrectomy. GGCX mutations in all 15 exons were examined in 44 patients with calcium oxalate urolithiasis (COU) by polymerase chain reaction (PCR) and denatured high pressure liquid chromatography (DHPLC), and confirmed by sequencing. Mutation was not found in all COU samples compared to the controls. These data demonstrated that functional GGCX mutations in all 15 exons do not occur in most COU patients. It was suggested that there may be no significant association between the low activity and mutation of GGCX in COU.
基金supported by the 12th five-year National Science and Technology plan of China(2012BAC01B03)the 111 Project of China(B13007)
文摘Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active compound contained in P. amurense. Our objective in this study was to quantify the content of berberine in P.amurense from sites at different elevations on Changbai Mountain. We collected samples of P. amurense from five different elevations on Changbai Mountain. Berberine in samples was extracted by ultrahigh pressure extraction(UPE). And the quantity was measured by high performance liquid chromatography(HPLC). First, the optimal HPLC conditions for berberine were identified with satisfactory precision(relative standard deviation, R SD/5.6 %), good accuracy(relative error, R E/ 3.6 %) and good linear relation(R2= 0.9998) in the range of 6.576–328.8 mg L-1. Second, the combination of UPE and HPLC methods in quantitative analysis of berberine showed high repeatability(R SD= 3.28 %), reproducibility(R SD= 4.72 %),stability(R SD/ 1.27 %) and good recovery(99.54 %) for real plant materials. Samples from Heilongjiang Province at the lowest elevation contained the highest amount of berberine.Similarly, the lowest amount of berberine was recorded in samples from Changbai Forest Bureau of Jilin Province collected at the highest elevation in this paper. The proposed UPE–HPLC method is simple, reliable and low-cost for quantitative analysis of berberine. Content of berberine in P.amurense varied significantly by site on Changbai Mountain.
基金support from the National Science Foundation (Nos. EAR-0001088, 0711057, and 1214376)Guoyin Shen acknowledges support from the DOE (Nos. DE-NA0001974 and DE-FG02-99ER45775)+5 种基金COMPRES for the support in developing the PEP system. Portions of this work were performed at GeoS oilE nviroC ARS (Sector 13), Advanced Photon Source (APS), Argonne National LaboratoryGeo Soil Enviro CARS is supported by the National Science Foundation-Earth Sciences (No. EAR-1128799)Department of Energy-Geo Sciences (No. DE-FG02-94ER14466)HPCAT operations are supported by DOE-NNSA under Award (Nos. DE-NA0001974)DOE-BES under Award (No. DE-FG02-99ER45775), with partial instrumentation funding by NSFUse of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract (No. DE-AC02-06CH11357)
文摘We review recent progress in studying silicate, carbonate, and metallic liquids of geological and geophysical importance at high pressure and temperature, using the large-volume high-pressure devices at the third-generation synchrotron facility of the Advanced Photon Source, Argonne National Laboratory. These integrated high-pressure facilities now offer a unique combination of experimental techniques that allow researchers to investigate structure, density, elasticity, viscosity, and interfacial tension of geo-liquids under high pressure, in a coordinated and systematic fashion. Experimental techniques are described, along with scientific highlights. Future developments are also discussed.
基金financially supported by the National Key R&D Program of China(2016YFC0600104)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(XDB 18010401)+1 种基金the National Natural Science Foundation of China(41902043)the Science and Technology Foundation Project in Guizhou Province([2019]1316,[2020]1Z032)。
文摘This paper introduces a 100 MPa water gas twophase fluid pressurization device.The device can provide 100 MPa gas pressure and 200 MPa liquid pressure for small volume(<20 mL)high-pressure experimental devices.This device can make the pressure control independent of the temperature control without changing the material components of the system.The resolution of this device in adjusting the pressure is±0.2 MPa in the process of boosting and depressurizing.This pressure boosting device generates very little vibration during work and it can be used in experiments with strict requirements on vibration.As a thermodynamic parameter,pressure has a great influence on matter.In the field of experimental geochemistry,pressure is not only an experimental method and an extreme condition but an important physical parameter independent of temperature and chemical composition.
文摘An apparatus for measuring solubilities of gases in liquids at elevated temperatures and pressures has been constructed. Using this apparatus, the slubilities of N_2 and CO_2 in some solvents have been determined in the temperature range between 20 and 230℃, and at pressures up to 130 atm. The experimental results obtained generally agree well with literature values. It is shown that this apparatus is reliable; attainment of equilibria needs only about 5 hours; precision of the measure- ments is ±0.2%.
基金supported by the NQI Project of National key R&D Program of China (No.2016YFF0201102)the project for the“Development of analytical method and certified reference materials for tracing air pollutant source” (No.21AKY1514)from the National Institute of Metrology,Beijing,China。
文摘A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.
基金EU MIRACLES project(Seventh Framework Programme KBBE-Grant Agreement No.613588,Multi-product Integrated bioRefinery of Algae:from Carbon dioxide and Light Energy to high-value Specialties).
文摘Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas sp.An experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC tests.All the extracts show significant antioxidant activity in all assays.Besides,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.
基金Supported by the National Natural Science Foundation of China:Study on Processing Mechanism of Jinger Juice-processed Rhizoma Coptidis Based on Nature,Pharmaceutical Effects and Material Base(No.81260643)Study on Mechanism Of Difference Of Ginger Juice Made From Zingiberis Rhizoma Recens and Zingiberis Rhizoma Relating to Processing(No.81460605)+1 种基金Study on the Mechanism of The Change of Nature of Aconitum Processed with Ginger Juice Based on the Theory of’Treating the Drug Being Hot Nature with Hot-natured Assistant to Strength the Hot Nature of The Drug’(No.81660663)Jiangxi Provincial Special Fund for Innovation of Postgraduates in 2019:Efficacy Evaluation of Traditional Jianchangbang Yinfupian and Yangfupian in the Treatment of Male and Female Yang-deficiency Syndrome(No.YC2019-B112)。
文摘OBJECTIVE:To investigate the relationship between the cardiotonic activity of Fuzi(Radix Aconiti Lateralis Preparata,RALP)and its fingerprint determined by liquid chromatography-mass spectrometry(LC-MS).METHODS:First,the fingerprints of six processed products of RALP were established by high performance liquid chromatography quadrupole time-of-flight mass spectrometry(HPLC-Q-TOF-MS)followed by analysis of the principal component of the relative peak area of its common peaks.Next,the scores of the first five principal components were used as input for an artificial neural network(ANN).Additionally,the therapeutic effect of RALP was assessed by measuring the hemodynamic indexes of heart failure model rats.Subsequently,fluorescence semi-quantitative polymerase chain reaction and an enzyme-linked immunosorbent assay kit were used to determine the effects of RALP-processed products on the serum levels of noradrenaline(NA),angiotensin-Ⅰ(Ang-Ⅰ),and the expression ofβ-norepinephrine receptor m RNA(β-NRm)in the rat cardiac tissues.P<0.05 was used as the output of the ANN.Finally,a network was constructed to display the relationship between the LC-MS fingerprints and the cardiotonic activity of the RALP-processed products.RESULTS:Several types of RALPs can improve diastolic function,systolic function and heart rate.On the basis of the findings from the principal component analysis(PCA)of 16 common peaks of fingerprints of six RALP-processed products,it was revealed that the first five principal components may include 100%of the information of the original data.As observed from the multilayer perceptron neural network analysis,principal component 4 presented with the strongest effects on serum levels of NA and Ang-Ⅰin rats,while principal component1 exerted the greatest effect onβ-NRm expression in cardiac tissue.CONCLUSION:The key findings obtained from this study indicated that the network constructed by the PCA-ANN may predict pharmacodynamic effects of the main ingredients of Traditional Chinese Medicine(TCM).This method may serve as a new approach to identify the relationship between LC-MS fingerprints and the pharmacodynamic effects of TCM ingredients.