In this paper, a back propagation artificial neural network (BP-ANN) model is presented for the simultaneous estimation of vapour liquid equilibria (VLE) of four binary systems viz chlorodifluoromethan-carbondioxi...In this paper, a back propagation artificial neural network (BP-ANN) model is presented for the simultaneous estimation of vapour liquid equilibria (VLE) of four binary systems viz chlorodifluoromethan-carbondioxide, trifluoromethan-carbondioxide, carbondisulfied-trifluoromethan and carbondisulfied-chlorodifluoromethan. VLE data of the systems were taken from the literature for wide ranges of temperature (222.04-343.23K) and pressure (0.105 to 7.46MPa). BP-ANN trained by the Levenberg-Marquardt algorithm in the MATLAB neural network toolbox was used for building and optimizing the model. It is shown that the established model could estimate the VLE with satisfactory precision and accuracy for the four systems with the root mean square error in the range of 0.054-0.119. Predictions using BP-ANN were compared with the conventional Redlich-Kwang-Soave (RKS) equation of state, suggesting that BP-ANN has better ability in estimation as compared with the RKS equation (the root mean square error in the range of 0.115-0.1546).展开更多
An experimental apparatus composed of microscope, video camera. image-processing, and mini reactor which can be used for real-time measurement of the growth of polymer particle in gas phase polymerization was built up...An experimental apparatus composed of microscope, video camera. image-processing, and mini reactor which can be used for real-time measurement of the growth of polymer particle in gas phase polymerization was built up to carry out dynamic study of gas phase polymerization of butadiene by heterogeneous catalyst based on neodymium(Nd). The studies of the shape duplication of polymer particles and catalyst particles and the growth rate of polymer particle were made. Results show that the apparatus and procedure designed can be well utilized to make dynamic observation and data collection of the growth of polymer particle in gas phase polymerization. A phenomenon of shape duplication of polymer particles and catalyst particles was observed by the real-time measurement. The result also concludes that the activity of individual catalyst particle is different, and the effect of reaction pressure on the growth of polymer particle is significant.展开更多
The solid-phase extraction using Pd-Al2O3 as the stationary phase was employed to pre-separate the sulfur compounds in straight-run diesel. The isolating effect was evaluated quantitatively by gas chromatography with ...The solid-phase extraction using Pd-Al2O3 as the stationary phase was employed to pre-separate the sulfur compounds in straight-run diesel. The isolating effect was evaluated quantitatively by gas chromatography with a sulfur chemiluminescence detector to harvest a satisfactory result. The identification of the structure of sulfur compounds by comprehensive two-dimensional gas chromatography coupled with the time-of-flight mass spectrometry indicated that cyclo-sulfides, benzothiophenes, dibenzothiophenes, dihydro-benzothiophenes and tetrahydro-dibenzothiophenes were included in straightrun diesel obtained from the Arab medium crude(AM). A total of 259 individual compounds were detected and their molecular structures were identified. The analytical method was approved as an effective way to characterize the composition of sulfur compounds, which reduced the interference of other compounds, facilitated the data presentation and provided more detailed information about molecular composition of sulfur compounds.展开更多
An analytical method for quantifying biomarker compounds of the sterane and the hopane existing in saturated hydrocarbons has been established by using comprehensive two-dimensional gas chromatography-flame ionization...An analytical method for quantifying biomarker compounds of the sterane and the hopane existing in saturated hydrocarbons has been established by using comprehensive two-dimensional gas chromatography-flame ionization detector(GC×GC-FID) with optimized operating parameters. The new method achieves the quantification by using a GC×GC-FID system which is able to completely separate steranes from hopanes. The data obtained by the new method are of good repeatability and reliability. Compared with the original data, the relative standard deviations(RSDs) of 12 reference compounds are less than 5%. The RSDs of the quantitative results of the biomarkers based on seven separate analyses are also less than 5%. Compared with the traditional method of gas chromatography-mass spectrometry(GC-MS), the new method has a number of advantages, such as common internal standards(ISs), high resolution, no co-eluting peak, and no interference caused by diagnostic ion peaks. The new method provides petroleum geologists with an effective and scientific means in future researches.展开更多
The saturated hydrocarbon fraction of a heavily biodegraded crude oil from Liaohe oilfield was analyzed by using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×...The saturated hydrocarbon fraction of a heavily biodegraded crude oil from Liaohe oilfield was analyzed by using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). The "humps", which was termed as unresolved complex mixtures (UCMs) in conventional gas chromatographic analysis, was separated for identification of the individual compound. Main compounds of UCMs were identified according to the combined information of characteristics of GC×GC chromatogram and time-of-flight mass spectra. It's found that UCMs are mainly composed of great number of ring compounds with extremely low concentration. The ring compounds are separated according to their boiling point diversity in the first dimension column, then to their polarity or ring number variety in the second dimension column. In the sample there are two groups of UCMs, i.e., the first group compounds with boiling point lower that of C24 and the second group compounds with boiling point higher than that of C24. The first group of UCMs mainly consists of monocyclic, bicyclic and tricyclic ring compounds. The first group of UCMs is mainly composed of saturated hydrocarbons, in which the percentage of ring compounds with signal-to-noise ratio above 100 is about 75% of the total quantity of saturated hydrocarbon, while its mass is over 80% of the total saturated hydrocarbon. The second group of UCMs is mainly composed of tetracyclic and pentacyclic ring compounds, in which the percentage of UCM compounds with signal-to-noise ratio over 100 is about 17% of the total quantity of saturated hydrocarbon, and its mass is about 0.5% of the total saturated hydrocarbon. The results of this study are helpful for heavy oil developing and genesis mechanism understanding.展开更多
文摘In this paper, a back propagation artificial neural network (BP-ANN) model is presented for the simultaneous estimation of vapour liquid equilibria (VLE) of four binary systems viz chlorodifluoromethan-carbondioxide, trifluoromethan-carbondioxide, carbondisulfied-trifluoromethan and carbondisulfied-chlorodifluoromethan. VLE data of the systems were taken from the literature for wide ranges of temperature (222.04-343.23K) and pressure (0.105 to 7.46MPa). BP-ANN trained by the Levenberg-Marquardt algorithm in the MATLAB neural network toolbox was used for building and optimizing the model. It is shown that the established model could estimate the VLE with satisfactory precision and accuracy for the four systems with the root mean square error in the range of 0.054-0.119. Predictions using BP-ANN were compared with the conventional Redlich-Kwang-Soave (RKS) equation of state, suggesting that BP-ANN has better ability in estimation as compared with the RKS equation (the root mean square error in the range of 0.115-0.1546).
基金the National Natural Science Foundation of China (No. 29876035).
文摘An experimental apparatus composed of microscope, video camera. image-processing, and mini reactor which can be used for real-time measurement of the growth of polymer particle in gas phase polymerization was built up to carry out dynamic study of gas phase polymerization of butadiene by heterogeneous catalyst based on neodymium(Nd). The studies of the shape duplication of polymer particles and catalyst particles and the growth rate of polymer particle were made. Results show that the apparatus and procedure designed can be well utilized to make dynamic observation and data collection of the growth of polymer particle in gas phase polymerization. A phenomenon of shape duplication of polymer particles and catalyst particles was observed by the real-time measurement. The result also concludes that the activity of individual catalyst particle is different, and the effect of reaction pressure on the growth of polymer particle is significant.
基金financially supported by the National Basic Research Program of China (973 Program) (2012CB224800)
文摘The solid-phase extraction using Pd-Al2O3 as the stationary phase was employed to pre-separate the sulfur compounds in straight-run diesel. The isolating effect was evaluated quantitatively by gas chromatography with a sulfur chemiluminescence detector to harvest a satisfactory result. The identification of the structure of sulfur compounds by comprehensive two-dimensional gas chromatography coupled with the time-of-flight mass spectrometry indicated that cyclo-sulfides, benzothiophenes, dibenzothiophenes, dihydro-benzothiophenes and tetrahydro-dibenzothiophenes were included in straightrun diesel obtained from the Arab medium crude(AM). A total of 259 individual compounds were detected and their molecular structures were identified. The analytical method was approved as an effective way to characterize the composition of sulfur compounds, which reduced the interference of other compounds, facilitated the data presentation and provided more detailed information about molecular composition of sulfur compounds.
文摘An analytical method for quantifying biomarker compounds of the sterane and the hopane existing in saturated hydrocarbons has been established by using comprehensive two-dimensional gas chromatography-flame ionization detector(GC×GC-FID) with optimized operating parameters. The new method achieves the quantification by using a GC×GC-FID system which is able to completely separate steranes from hopanes. The data obtained by the new method are of good repeatability and reliability. Compared with the original data, the relative standard deviations(RSDs) of 12 reference compounds are less than 5%. The RSDs of the quantitative results of the biomarkers based on seven separate analyses are also less than 5%. Compared with the traditional method of gas chromatography-mass spectrometry(GC-MS), the new method has a number of advantages, such as common internal standards(ISs), high resolution, no co-eluting peak, and no interference caused by diagnostic ion peaks. The new method provides petroleum geologists with an effective and scientific means in future researches.
文摘The saturated hydrocarbon fraction of a heavily biodegraded crude oil from Liaohe oilfield was analyzed by using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). The "humps", which was termed as unresolved complex mixtures (UCMs) in conventional gas chromatographic analysis, was separated for identification of the individual compound. Main compounds of UCMs were identified according to the combined information of characteristics of GC×GC chromatogram and time-of-flight mass spectra. It's found that UCMs are mainly composed of great number of ring compounds with extremely low concentration. The ring compounds are separated according to their boiling point diversity in the first dimension column, then to their polarity or ring number variety in the second dimension column. In the sample there are two groups of UCMs, i.e., the first group compounds with boiling point lower that of C24 and the second group compounds with boiling point higher than that of C24. The first group of UCMs mainly consists of monocyclic, bicyclic and tricyclic ring compounds. The first group of UCMs is mainly composed of saturated hydrocarbons, in which the percentage of ring compounds with signal-to-noise ratio above 100 is about 75% of the total quantity of saturated hydrocarbon, while its mass is over 80% of the total saturated hydrocarbon. The second group of UCMs is mainly composed of tetracyclic and pentacyclic ring compounds, in which the percentage of UCM compounds with signal-to-noise ratio over 100 is about 17% of the total quantity of saturated hydrocarbon, and its mass is about 0.5% of the total saturated hydrocarbon. The results of this study are helpful for heavy oil developing and genesis mechanism understanding.