Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated....Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated. New modified multi-parameter techniques, developed fromCrisfield's multi-parameter methods, are utilized to solve these nonlinear equations. The numericalperformance of these techniques is compared with the standard Newton-Raphson method (sN-R),Crisfield's single parameter method (C1), Crisfield's two parameter method (C2) and Crisfield'sthree parameter method (C3). The new techniques do not involve additional residual force calculationand require little extra computational effort. In addition, they are more robust and efficient thanother existing acceleration techniques.展开更多
Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of va...Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards.展开更多
It was concluded that the described HPLC method could be used for the assayof salmon calcitonin in injection, as it offers qualified selectivity, accuracy and precision ofanalysis.
A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, ...A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn Sb, Ba, Pt, Au, and Pb) in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCI. The matrix effects because of the presence of excess HCI and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits were 0.016-1.50 ].tg·g^-1, the recovery ratios were 92.2%-111.2%, and the RSD was less than 3.6%. The method was accurate, quick, and convenient. It was applied to the determination of trace impurities in high purity cobalt with satisfactory results.展开更多
Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series du...Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series due to the"segment length curse".To alleviate the segment length curse and thus improve the standardization method for developing long tree-ring chronologies,here we first calculated a mean value for all the tree ring series by overlapping all of the tree ring series.The growth trend of the mean tree ring width(i.e.,cumulated average growth trend of all the series)was determined using ensemble empirical mode decomposition.Then the chronology was developed by dividing the mean value by the growth trend of the mean value.Our improved method alleviated the problem of trend distortion.Long-term signals were better preserved using the improved method than in previous detrending methods.The chronologies developed using the improved method were better correlated with climate than those developed using conservative methods.The improved standardization method alleviates trend distortion and retains more of the low-frequency climate signals.展开更多
The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,sm...The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,smart systems,and a smart network.In this context,which is characterized by a large gap between training and operative processes,a dedicated method is required to manage and extract the massive amount of data and the related information mining.The method presented in this work aims to reduce this gap with near-zero-failure advanced diagnostics(AD)for smart management,which is exploitable in any context of Society 5.0,thus reducing the risk factors at all management levels and ensuring quality and sustainability.We have also developed innovative applications for a humancentered management system to support scheduling in the maintenance of operative processes,for reducing training costs,for improving production yield,and for creating a human–machine cyberspace for smart infrastructure design.The results obtained in 12 international companies demonstrate a possible global standardization of operative processes,leading to the design of a near-zero-failure intelligent system that is able to learn and upgrade itself.Our new method provides guidance for selecting the new generation of intelligent manufacturing and smart systems in order to optimize human–machine interactions,with the related smart maintenance and education.展开更多
Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and perman...Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and permanent gases, such as CO2, H2S, H2, and CO, for direct coal liquefaction has been realized. With four packed chromatographic columns, which are Hayesep-Q pre-column, Hayesep-Q column, molecular sieve 5A column and one PLOT A1203 S capillary column, the gas compositions for direct coal liquefaction are analyzed qualitatively and quantitatively by the external standard method. The determination method has such advantages as excellent separation, simple operation, rapid analysis and accurate results.展开更多
Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) has become a powerful tool for analyzing the detailed composition of petroleum samples. However, the correlation between the numerous peaks obtain...Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) has become a powerful tool for analyzing the detailed composition of petroleum samples. However, the correlation between the numerous peaks obtained by FT-ICR MS and bulk properties of petroleum samples is still a challenge. In this study, the internal standard method was applied for the quantitative analysis of four straight-run vacuum gas oils(VGO) by atmospheric pressure photoionization(APPI) FT-ICR MS. The heteroatom class distribution of these VGO samples turned to be different when the concentration changed. Linear relationship between the normalized abundance and the concentration of VGO samples was identified for the total aromatic compounds, aromatic hydrocarbons, S1 and N1 species. The differences of the response factors were also discussed. The sulfur contents of a series of crude oils were proved to be linear with the FT-ICR MS data calibrated by the response factor of S1 species. This study demonstrated the feasibility of the internal standard method in quantitative analysis with APPI FT-ICR MS, and the bulk properties of petroleum samples could be correlated directly with the FT-ICR MS data.展开更多
Sulfur speciation and concentration in geothermal water are of great significance for the research and utilization of the water resources.In most situations,it is necessary to determine the total sulfur in geothermal ...Sulfur speciation and concentration in geothermal water are of great significance for the research and utilization of the water resources.In most situations,it is necessary to determine the total sulfur in geothermal water.In this study,the method was established for the determination of determining total sulfur content-the inductively coupled plasma-atomic emission spectrometry(ICP-AES),with the wavelength of 182.034 nm selected in spectral line of sulfur.It was identified that the optimal working conditions of the ICP-AES instrument were 1200 W for high frequency generator power 9 mm for vertical observation height,0.30 MPa atomizer pressure,and 50 r/min analytical pump speed.The matrix interference of the method was eliminated by the matrix matching method.Using this method,sulfur detection limit and minimum quantitative detection limit were 0.028 mg/L and 0.110 mg/L,respectively,whilst the linear range was 0.0-100.0 mg/L.The recovery rate of sample was between 90.67%and 108.7%,and the relative standard deviation(RSD)was between 0.36%and 2.14%.The method was used to analyze the actual samples and the results were basically consistent with the industry standard method.With high analysis efficiency,the method has low detection limit and minimum quantitative detection limit,wide linear range,good precision and accuracy,and provides an important detection method for the determination of total sulfur in geothermal water.展开更多
AIM:To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS:Fifty volunteers were enrolled in ...AIM:To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS:Fifty volunteers were enrolled in this study in the Ophthalmological Clinic of Cluj-Napoca,Romania,between January 2012 and January 2014. A set of 100 segmented and skeletonised human retinal images,corresponding to normal states of the retina were studied. An automatic unsupervised method for retinal vessel segmentation was applied before multifractal analysis. The multifractal analysis of digital retinal images was made with computer algorithms,applying the standard boxcounting method. Statistical analyses were performed using the Graph Pad In Stat software.RESULTS:The architecture of normal human retinal microvascular network was able to be described using the multifractal geometry. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα=α_(max)-α_(min))and the spectrum arms' heights difference(│Δf│)of the normal images were expressed as mean±standard deviation(SD):for segmented versions,D_0=1.7014±0.0057; D_1=1.6507±0.0058; D_2=1.5772±0.0059; Δα=0.92441±0.0085; │Δf│= 0.1453±0.0051; for skeletonised versions,D_0=1.6303±0.0051; D_1=1.6012±0.0059; D_2=1.5531± 0.0058; Δα=0.65032±0.0162; │Δf│= 0.0238±0.0161. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα)and the spectrum arms' heights difference(│Δf│)of the segmented versions was slightly greater than the skeletonised versions.CONCLUSION:The multifractal analysis of fundus photographs may be used as a quantitative parameter for the evaluation of the complex three-dimensional structure of the retinal microvasculature as a potential marker for early detection of topological changes associated with retinal diseases.展开更多
In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of method...In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of methods such as high voltage electric field treatment,the transfer matrix method and the CIE standard colorimetric system were simulated to obtain the chromaticity coordinates and to analyze the color changes of KGM particles. The results revealed that as the particle diameter increases,the structural color of KGM particles deflects towards the yellow wavelength within the visible spectrum; and as the reaction temperature rises,the structural color deflects towards the blue and violet wavelengths within the visible spectrum.展开更多
In this study, we present a PSHA(Probabilistic Seismic Hazard Analysis) for the city of San Juan, which is located in the central-western region of Argentina(30°S-35.5°S; 66.5°W-71°W). In addit...In this study, we present a PSHA(Probabilistic Seismic Hazard Analysis) for the city of San Juan, which is located in the central-western region of Argentina(30°S-35.5°S; 66.5°W-71°W). In addition to crustal earthquakes provided by catalogues, recent paleoseismological and neotectonic investigations have permitted to consider events which occurred during the last 400 years.Four seismogenic sources that could cause damages to the studied site corresponding to Precordillera,Western Sierras Pampeanas, Basement of the Cuyana Basin and Cordillera Principal were identified.Based on the evaluation of the contribution of these sources,maximum moment magnitudes above 7.5(Mw) are expected.High values of SA(spectral acceleration)(0.2 and 1 s periods) and PGA(peak ground acceleration) were found in the city of San Juan, which suggests that it is located in a zone of high seismic hazard.Finally, the obtained SA spectra were compared with the seismic-resistant construction standards of Argentina INPRES-CIRSOC 103 [1]. Results suggest that for the city of San Juan and for a return period of475 years, it covers the seismic requirements of the structures.展开更多
[Objective]This study was to establish a rapid,specific and simple method for quantitative determination of tetrachlorantraniliprole by 1H NMR.[Method]1H NMR spectroscopy was acquired with deuterium DMSO as the solven...[Objective]This study was to establish a rapid,specific and simple method for quantitative determination of tetrachlorantraniliprole by 1H NMR.[Method]1H NMR spectroscopy was acquired with deuterium DMSO as the solvent and maleic acid as internal standard under the conditions of temperature 25℃,pulses width 8.0μs,delay time 5 s,and scanning times 8.[Result]The hydrogen proton peaks of tetrachlorantraniliprole(δ=10.55)and maleic acid(δ=6.27)were taken as quantitative peaks.The peak area ratio y(As/Ar)and mass ratio x(ms/mr)were linearly regressed,and the correlation coefficient was 0.9999.The RSD value of repeatability test was 0.38%,and the RSD value of stability test was 0.77%.The content of tetrachlorantraniliprole was determined as 99.6%.[Conclusion]1H NMR spectroscopy can be used for quantitative determination of tetrachlorantraniliprole without standard reference,which is rapid,accurate and simple.展开更多
The weakly forced vibration of an axially moving viscoelastic beam is inves- tigated. The viscoelastic material of the beam is constituted by the standard linear solid model with the material time derivative involved....The weakly forced vibration of an axially moving viscoelastic beam is inves- tigated. The viscoelastic material of the beam is constituted by the standard linear solid model with the material time derivative involved. The nonlinear equations governing the transverse vibration are derived from the dynamical, constitutive, and geometrical relations. The method of multiple scales is used to determine the steady-state response. The modulation equation is derived from the solvability condition of eliminating secular terms. Closed-form expressions of the amplitude and existence condition of nontrivial steady-state response are derived from the modulation equation. The stability of non- trivial steady-state response is examined via the Routh-Hurwitz criterion.展开更多
To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinc...To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods(spot, filter paper and standard methods) at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease(P ≤ 0.05). Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.展开更多
a special penalty method is presented to improve the accuracy of the standard penalty method for solving Stokes equation with nonconforming finite element.It is shown that this method with a larger penalty parameter c...a special penalty method is presented to improve the accuracy of the standard penalty method for solving Stokes equation with nonconforming finite element.It is shown that this method with a larger penalty parameter can achieve the same accuracy as the standard method with a smaller penalty parameter. The convergence rate of the standard method is just half order of this penalty method when using the same penalty parameter, while the extrapolation method proposed by Faik et al can not yield so high accuracy of convergence.At last, we also get the super convergence estimates for total flux. Received October 14, 1996 1991 MR Subject Classification: 65N30.展开更多
Dispersion parameter is an important parameter for the establishment of groundwater solute transport model.The dispersion test uses sodium chloride as a tracer,which was conducted in a site in Jilin City.The standard ...Dispersion parameter is an important parameter for the establishment of groundwater solute transport model.The dispersion test uses sodium chloride as a tracer,which was conducted in a site in Jilin City.The standard curve comparison method was used to solve the dispersion parameters of the aquifer under the natural flow field.The test results show that under the natural flow field,the longitudinal dispersion of unconfined aquifer in Jilin City is 0.400m,and the transverse dispersion is 1.933×10-5~6.557×10-3m;while the longitudinal dispersion coefficient is 0.246m2/d,the transverse dispersion coefficient is 1.191×10-5~4.039×10-3m2/d.The above results can provide an important parameter basis for the establishment of groundwater solute transport model,the accurate prediction of temporal and spatial variation of pollutant concentration in groundwater and the formulation of groundwater pollution prevention and control scheme.展开更多
The purpose of this paper is to analyze the mistakes that are typically made in the choosing of current appraisal assessment methods for investment decisions. Aider research and comparison of three assessment methods,...The purpose of this paper is to analyze the mistakes that are typically made in the choosing of current appraisal assessment methods for investment decisions. Aider research and comparison of three assessment methods, the relationships among the objectives of valuation, valuation standards and appraisal means are established. Furthermore, the effects of the appraisal measures chosen are empirically analyzed.展开更多
The supervision and administration of cosmetics and its two supporting documents related to efficacy,cosmetics classification rules and classification catalogue and evaluation standard of cosmetic efficacy claims,have...The supervision and administration of cosmetics and its two supporting documents related to efficacy,cosmetics classification rules and classification catalogue and evaluation standard of cosmetic efficacy claims,have been successively introduced and implemented,making China’s cosmetics industry officially enter the era of efficacy evaluation.In the time window when the new era is coming,the definitions of cosmetics in China and other countries are compared.The latest status and progress of regulations on cosmetic efficacy claims in China and other countries are summarized,and the standard methods or guidance of cosmetic efficacy evaluation at home and abroad are introduced.The enlightenment from the supervision systems of cosmetic efficacy in other cosmetic consumer markets around the world are discussed.In addition,the opportunities and challenges for cosmetic enterprises under the background of cosmetic law reform in China are also prospected.展开更多
In this article, a new method for simultaneous determination of six phthalate esters was developed by a combination of electrospun nylon6 nanofibers mat-based solid phase extraction with high performance liquid chroma...In this article, a new method for simultaneous determination of six phthalate esters was developed by a combination of electrospun nylon6 nanofibers mat-based solid phase extraction with high performance liquid chromatography-ultraviolet detector (HPLC-UV). The six phthalate esters were dimethyl phthalate (DMP), diethyl phthalate (DEP), butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP) and dioctyl phthalate (DOP). Under optimized conditions, all target analytes in 50 mL environmental water samples could be completely extracted by 2.5 mg nylon6 nanofibers mat and eluted by 100 μL solvent. Compared with C18 cartridges solid phase extraction, C 18 disks solid phase extraction and national standard method (China), nylon6 nanofibers mat-based solid phase extraction was advantageous in aspects of simple and fast operation, low consumption of extraction materials and organic solvents. The four methods were applied to analysis of environment water samples. All the results indicated that the determination values of target compounds with the proposed method were consistent with C18 cartridges and C18 disks solid phase extraction method, and the new method was better than the national standard method in aspects of recovery, LOD and precision. Therefore, nylon6 nanofibers mat has great potential as a novel material for solid phase extraction.展开更多
文摘Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated. New modified multi-parameter techniques, developed fromCrisfield's multi-parameter methods, are utilized to solve these nonlinear equations. The numericalperformance of these techniques is compared with the standard Newton-Raphson method (sN-R),Crisfield's single parameter method (C1), Crisfield's two parameter method (C2) and Crisfield'sthree parameter method (C3). The new techniques do not involve additional residual force calculationand require little extra computational effort. In addition, they are more robust and efficient thanother existing acceleration techniques.
文摘Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards.
文摘It was concluded that the described HPLC method could be used for the assayof salmon calcitonin in injection, as it offers qualified selectivity, accuracy and precision ofanalysis.
基金the Natural Science Foundation of Hunan Province, China (No. 05JJ40017).
文摘A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn Sb, Ba, Pt, Au, and Pb) in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCI. The matrix effects because of the presence of excess HCI and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits were 0.016-1.50 ].tg·g^-1, the recovery ratios were 92.2%-111.2%, and the RSD was less than 3.6%. The method was accurate, quick, and convenient. It was applied to the determination of trace impurities in high purity cobalt with satisfactory results.
文摘Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series due to the"segment length curse".To alleviate the segment length curse and thus improve the standardization method for developing long tree-ring chronologies,here we first calculated a mean value for all the tree ring series by overlapping all of the tree ring series.The growth trend of the mean tree ring width(i.e.,cumulated average growth trend of all the series)was determined using ensemble empirical mode decomposition.Then the chronology was developed by dividing the mean value by the growth trend of the mean value.Our improved method alleviated the problem of trend distortion.Long-term signals were better preserved using the improved method than in previous detrending methods.The chronologies developed using the improved method were better correlated with climate than those developed using conservative methods.The improved standardization method alleviates trend distortion and retains more of the low-frequency climate signals.
文摘The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,smart systems,and a smart network.In this context,which is characterized by a large gap between training and operative processes,a dedicated method is required to manage and extract the massive amount of data and the related information mining.The method presented in this work aims to reduce this gap with near-zero-failure advanced diagnostics(AD)for smart management,which is exploitable in any context of Society 5.0,thus reducing the risk factors at all management levels and ensuring quality and sustainability.We have also developed innovative applications for a humancentered management system to support scheduling in the maintenance of operative processes,for reducing training costs,for improving production yield,and for creating a human–machine cyberspace for smart infrastructure design.The results obtained in 12 international companies demonstrate a possible global standardization of operative processes,leading to the design of a near-zero-failure intelligent system that is able to learn and upgrade itself.Our new method provides guidance for selecting the new generation of intelligent manufacturing and smart systems in order to optimize human–machine interactions,with the related smart maintenance and education.
文摘Via multi-dimensional gas chromatography, configured with parallel dual-channel, double detectors, valves switching and back flushing, rapid analysis of the gas compositions consisting of C1-C5 hydrocarbons and permanent gases, such as CO2, H2S, H2, and CO, for direct coal liquefaction has been realized. With four packed chromatographic columns, which are Hayesep-Q pre-column, Hayesep-Q column, molecular sieve 5A column and one PLOT A1203 S capillary column, the gas compositions for direct coal liquefaction are analyzed qualitatively and quantitatively by the external standard method. The determination method has such advantages as excellent separation, simple operation, rapid analysis and accurate results.
基金supported by the Major State Basic Research Development Program of China(973 Program,No.2012CB224801)
文摘Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) has become a powerful tool for analyzing the detailed composition of petroleum samples. However, the correlation between the numerous peaks obtained by FT-ICR MS and bulk properties of petroleum samples is still a challenge. In this study, the internal standard method was applied for the quantitative analysis of four straight-run vacuum gas oils(VGO) by atmospheric pressure photoionization(APPI) FT-ICR MS. The heteroatom class distribution of these VGO samples turned to be different when the concentration changed. Linear relationship between the normalized abundance and the concentration of VGO samples was identified for the total aromatic compounds, aromatic hydrocarbons, S1 and N1 species. The differences of the response factors were also discussed. The sulfur contents of a series of crude oils were proved to be linear with the FT-ICR MS data calibrated by the response factor of S1 species. This study demonstrated the feasibility of the internal standard method in quantitative analysis with APPI FT-ICR MS, and the bulk properties of petroleum samples could be correlated directly with the FT-ICR MS data.
基金supported by the Fundamental Research Fund Project(SK201908)of the Institute of Hydrogeology and Environmental Geology,Chinese Academy of Geological Sciences.
文摘Sulfur speciation and concentration in geothermal water are of great significance for the research and utilization of the water resources.In most situations,it is necessary to determine the total sulfur in geothermal water.In this study,the method was established for the determination of determining total sulfur content-the inductively coupled plasma-atomic emission spectrometry(ICP-AES),with the wavelength of 182.034 nm selected in spectral line of sulfur.It was identified that the optimal working conditions of the ICP-AES instrument were 1200 W for high frequency generator power 9 mm for vertical observation height,0.30 MPa atomizer pressure,and 50 r/min analytical pump speed.The matrix interference of the method was eliminated by the matrix matching method.Using this method,sulfur detection limit and minimum quantitative detection limit were 0.028 mg/L and 0.110 mg/L,respectively,whilst the linear range was 0.0-100.0 mg/L.The recovery rate of sample was between 90.67%and 108.7%,and the relative standard deviation(RSD)was between 0.36%and 2.14%.The method was used to analyze the actual samples and the results were basically consistent with the industry standard method.With high analysis efficiency,the method has low detection limit and minimum quantitative detection limit,wide linear range,good precision and accuracy,and provides an important detection method for the determination of total sulfur in geothermal water.
基金the Program"Partnerships in priority domains"with the support of the National Education Ministry,the Executive Agency for Higher Education,Research,Development and Innovation Funding (UEFISCDI),Romania (Project code:PN-II-PT-PCCA-2013-4-1232)
文摘AIM:To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS:Fifty volunteers were enrolled in this study in the Ophthalmological Clinic of Cluj-Napoca,Romania,between January 2012 and January 2014. A set of 100 segmented and skeletonised human retinal images,corresponding to normal states of the retina were studied. An automatic unsupervised method for retinal vessel segmentation was applied before multifractal analysis. The multifractal analysis of digital retinal images was made with computer algorithms,applying the standard boxcounting method. Statistical analyses were performed using the Graph Pad In Stat software.RESULTS:The architecture of normal human retinal microvascular network was able to be described using the multifractal geometry. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα=α_(max)-α_(min))and the spectrum arms' heights difference(│Δf│)of the normal images were expressed as mean±standard deviation(SD):for segmented versions,D_0=1.7014±0.0057; D_1=1.6507±0.0058; D_2=1.5772±0.0059; Δα=0.92441±0.0085; │Δf│= 0.1453±0.0051; for skeletonised versions,D_0=1.6303±0.0051; D_1=1.6012±0.0059; D_2=1.5531± 0.0058; Δα=0.65032±0.0162; │Δf│= 0.0238±0.0161. The average of generalized dimensions(D_q)for q=0,1,2,the width of the multifractal spectrum(Δα)and the spectrum arms' heights difference(│Δf│)of the segmented versions was slightly greater than the skeletonised versions.CONCLUSION:The multifractal analysis of fundus photographs may be used as a quantitative parameter for the evaluation of the complex three-dimensional structure of the retinal microvasculature as a potential marker for early detection of topological changes associated with retinal diseases.
基金supported by the National Natural Science Foundation of China(31271837 and 31471704)the major project of Fujian Industry-Academy-Research Cooperation(2013N5003)+1 种基金the Natural Science Foundation(2011J0101)of Fujian Province,the Science and Technology Program under Fujian Provincial Department of Education(JA13439 and JA13440)the Science and Technology Program under Fujian Provincial Department of Forestry(20135)
文摘In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of methods such as high voltage electric field treatment,the transfer matrix method and the CIE standard colorimetric system were simulated to obtain the chromaticity coordinates and to analyze the color changes of KGM particles. The results revealed that as the particle diameter increases,the structural color of KGM particles deflects towards the yellow wavelength within the visible spectrum; and as the reaction temperature rises,the structural color deflects towards the blue and violet wavelengths within the visible spectrum.
文摘In this study, we present a PSHA(Probabilistic Seismic Hazard Analysis) for the city of San Juan, which is located in the central-western region of Argentina(30°S-35.5°S; 66.5°W-71°W). In addition to crustal earthquakes provided by catalogues, recent paleoseismological and neotectonic investigations have permitted to consider events which occurred during the last 400 years.Four seismogenic sources that could cause damages to the studied site corresponding to Precordillera,Western Sierras Pampeanas, Basement of the Cuyana Basin and Cordillera Principal were identified.Based on the evaluation of the contribution of these sources,maximum moment magnitudes above 7.5(Mw) are expected.High values of SA(spectral acceleration)(0.2 and 1 s periods) and PGA(peak ground acceleration) were found in the city of San Juan, which suggests that it is located in a zone of high seismic hazard.Finally, the obtained SA spectra were compared with the seismic-resistant construction standards of Argentina INPRES-CIRSOC 103 [1]. Results suggest that for the city of San Juan and for a return period of475 years, it covers the seismic requirements of the structures.
文摘[Objective]This study was to establish a rapid,specific and simple method for quantitative determination of tetrachlorantraniliprole by 1H NMR.[Method]1H NMR spectroscopy was acquired with deuterium DMSO as the solvent and maleic acid as internal standard under the conditions of temperature 25℃,pulses width 8.0μs,delay time 5 s,and scanning times 8.[Result]The hydrogen proton peaks of tetrachlorantraniliprole(δ=10.55)and maleic acid(δ=6.27)were taken as quantitative peaks.The peak area ratio y(As/Ar)and mass ratio x(ms/mr)were linearly regressed,and the correlation coefficient was 0.9999.The RSD value of repeatability test was 0.38%,and the RSD value of stability test was 0.77%.The content of tetrachlorantraniliprole was determined as 99.6%.[Conclusion]1H NMR spectroscopy can be used for quantitative determination of tetrachlorantraniliprole without standard reference,which is rapid,accurate and simple.
基金Project supported by the National Natural Science Foundation of China (No.10972143)the Shanghai Municipal Education Commission (No.YYY11040)+2 种基金the Shanghai Leading Academic Discipline Project (No.J51501)the Leading Academic Discipline Project of Shanghai Institute of Technology(No.1020Q121001)the Start Foundation for Introducing Talents of Shanghai Institute of Technology (No.YJ2011-26)
文摘The weakly forced vibration of an axially moving viscoelastic beam is inves- tigated. The viscoelastic material of the beam is constituted by the standard linear solid model with the material time derivative involved. The nonlinear equations governing the transverse vibration are derived from the dynamical, constitutive, and geometrical relations. The method of multiple scales is used to determine the steady-state response. The modulation equation is derived from the solvability condition of eliminating secular terms. Closed-form expressions of the amplitude and existence condition of nontrivial steady-state response are derived from the modulation equation. The stability of non- trivial steady-state response is examined via the Routh-Hurwitz criterion.
文摘To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods(spot, filter paper and standard methods) at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease(P ≤ 0.05). Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.
文摘a special penalty method is presented to improve the accuracy of the standard penalty method for solving Stokes equation with nonconforming finite element.It is shown that this method with a larger penalty parameter can achieve the same accuracy as the standard method with a smaller penalty parameter. The convergence rate of the standard method is just half order of this penalty method when using the same penalty parameter, while the extrapolation method proposed by Faik et al can not yield so high accuracy of convergence.At last, we also get the super convergence estimates for total flux. Received October 14, 1996 1991 MR Subject Classification: 65N30.
基金National Joint Foundation for Natural Science Focus(Project No.:U 19A20107).
文摘Dispersion parameter is an important parameter for the establishment of groundwater solute transport model.The dispersion test uses sodium chloride as a tracer,which was conducted in a site in Jilin City.The standard curve comparison method was used to solve the dispersion parameters of the aquifer under the natural flow field.The test results show that under the natural flow field,the longitudinal dispersion of unconfined aquifer in Jilin City is 0.400m,and the transverse dispersion is 1.933×10-5~6.557×10-3m;while the longitudinal dispersion coefficient is 0.246m2/d,the transverse dispersion coefficient is 1.191×10-5~4.039×10-3m2/d.The above results can provide an important parameter basis for the establishment of groundwater solute transport model,the accurate prediction of temporal and spatial variation of pollutant concentration in groundwater and the formulation of groundwater pollution prevention and control scheme.
文摘The purpose of this paper is to analyze the mistakes that are typically made in the choosing of current appraisal assessment methods for investment decisions. Aider research and comparison of three assessment methods, the relationships among the objectives of valuation, valuation standards and appraisal means are established. Furthermore, the effects of the appraisal measures chosen are empirically analyzed.
文摘The supervision and administration of cosmetics and its two supporting documents related to efficacy,cosmetics classification rules and classification catalogue and evaluation standard of cosmetic efficacy claims,have been successively introduced and implemented,making China’s cosmetics industry officially enter the era of efficacy evaluation.In the time window when the new era is coming,the definitions of cosmetics in China and other countries are compared.The latest status and progress of regulations on cosmetic efficacy claims in China and other countries are summarized,and the standard methods or guidance of cosmetic efficacy evaluation at home and abroad are introduced.The enlightenment from the supervision systems of cosmetic efficacy in other cosmetic consumer markets around the world are discussed.In addition,the opportunities and challenges for cosmetic enterprises under the background of cosmetic law reform in China are also prospected.
基金Project supported by the National Natural Science Foundation of China (No. 9225000007), Southeast University and the Suzhou Science and Technology Development Projects (No. YJS0948).
文摘In this article, a new method for simultaneous determination of six phthalate esters was developed by a combination of electrospun nylon6 nanofibers mat-based solid phase extraction with high performance liquid chromatography-ultraviolet detector (HPLC-UV). The six phthalate esters were dimethyl phthalate (DMP), diethyl phthalate (DEP), butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP) and dioctyl phthalate (DOP). Under optimized conditions, all target analytes in 50 mL environmental water samples could be completely extracted by 2.5 mg nylon6 nanofibers mat and eluted by 100 μL solvent. Compared with C18 cartridges solid phase extraction, C 18 disks solid phase extraction and national standard method (China), nylon6 nanofibers mat-based solid phase extraction was advantageous in aspects of simple and fast operation, low consumption of extraction materials and organic solvents. The four methods were applied to analysis of environment water samples. All the results indicated that the determination values of target compounds with the proposed method were consistent with C18 cartridges and C18 disks solid phase extraction method, and the new method was better than the national standard method in aspects of recovery, LOD and precision. Therefore, nylon6 nanofibers mat has great potential as a novel material for solid phase extraction.