Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based o...Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and GC/MS analyses, the molecular compositions of NSO compounds in extracts from the Permian Dalong Formation, Sichuan Basin and the Permian Lucaogou Formation, Junggar Basin in China were compared. Analyses of types of heteroatoms present (S~, $2, $3, OS, OS2, 02S, NS, and NOS compounds) suggest that marine shales from the Dalong Formation are mainly composed of carboxylic acids (02 com- pounds) with a high abundance of fatty acids, indicating a marine phytoplankton organic source. However, lacustrine shales from the Lucaogou Formation are dominated by pyrrolic compounds (N1 compounds) with abundant dibenzocar- bazole. It suggests that the organic source materials may be derived from lower aquatic organisms and lacustrine algae. Overall, FT-ICR-MS has potential for applications in analyses and determination of depositional environments and organic sources in petroleum geology.展开更多
Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN...Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.展开更多
FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most freque...FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most frequently used proteomics approach,a single LC-MS run can reveal tens and even hundreds of useful information.For each peptide selected for MS/MS,two data-files were generated,one for ECD and another one for CAD.They were merged as described and submitted to the Mascot search engine using the protein database.These thresholds ensure almost 100% statistical confident in the peptide identification.展开更多
After digesting the protein of the human milk samples into different parts by trypsin,the compositions of protein were identified by FT-ICR-MS under ECD and CAD mode.The analysis of MS chromatograms was performed by t...After digesting the protein of the human milk samples into different parts by trypsin,the compositions of protein were identified by FT-ICR-MS under ECD and CAD mode.The analysis of MS chromatograms was performed by the Mascot database search software.The result showed that nano-spray HPLC combined with FT-MS could be used as a high efficient method for the identification of the protein in human milk samples.展开更多
The nitrogen-containing compounds in Changqing crude oil, its atmospheric residue(AR), and vacuum reside(VR) were characterized by negative and positive ion electrospray ionization(ESI) Fourier transform ion cyclotron...The nitrogen-containing compounds in Changqing crude oil, its atmospheric residue(AR), and vacuum reside(VR) were characterized by negative and positive ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). The heteroatom compounds(N_1, N_2, N_1O_1, O_1, and O_2 class species) could be identified by the negative ESI analysis, while the positive mode could only detect the N_1, N_2, and N_1O_1 class species. Among them, the N_1 class species were found to be predominant in crude oil, as confirmed by either negative or positive ESI analyses,which were similar in composition to AR and VR. These compounds with higher abundance were characterized by double bond equivalent(DBE) values and carbon numbers. The composition of these compounds in crude oil and its AR as well as VR was correlated with their different boiling range, DBE values and carbon numbers. The negative ESI analysis showed that the abundant N_1 class species in crude oil and AR were centered at a DBE value of 12, and these species were likely benzocarbazoles, while the N_1 class species with the DBE value ranging from 13 to 16 having more complicated molecular structures were dominant in VR. And the positive ESI analysis gave the information of the abundant N_1 class species in crude oil, AR, and VR having the DBE values in the range of 10, 9―11, and 10―16, respectively, which were likely the compounds with the core of quinoline and benzoquinoline. The analysis confirmed that the distillation process in refinery preferentially removed the low DBE value and low molecular N-class species and brought them into the light and medium distillates, while those N-class species having a high molecular condensation in the molecules with large carbon number remained in the residual oil and could continually affect the downstream oil refining process.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 41672117)Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals (Project No. DMSM201413)Hubei Provincial Natural Science Foundation of China (Project No. 2017CFA027)
文摘Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and GC/MS analyses, the molecular compositions of NSO compounds in extracts from the Permian Dalong Formation, Sichuan Basin and the Permian Lucaogou Formation, Junggar Basin in China were compared. Analyses of types of heteroatoms present (S~, $2, $3, OS, OS2, 02S, NS, and NOS compounds) suggest that marine shales from the Dalong Formation are mainly composed of carboxylic acids (02 com- pounds) with a high abundance of fatty acids, indicating a marine phytoplankton organic source. However, lacustrine shales from the Lucaogou Formation are dominated by pyrrolic compounds (N1 compounds) with abundant dibenzocar- bazole. It suggests that the organic source materials may be derived from lower aquatic organisms and lacustrine algae. Overall, FT-ICR-MS has potential for applications in analyses and determination of depositional environments and organic sources in petroleum geology.
文摘Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.
文摘FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most frequently used proteomics approach,a single LC-MS run can reveal tens and even hundreds of useful information.For each peptide selected for MS/MS,two data-files were generated,one for ECD and another one for CAD.They were merged as described and submitted to the Mascot search engine using the protein database.These thresholds ensure almost 100% statistical confident in the peptide identification.
文摘After digesting the protein of the human milk samples into different parts by trypsin,the compositions of protein were identified by FT-ICR-MS under ECD and CAD mode.The analysis of MS chromatograms was performed by the Mascot database search software.The result showed that nano-spray HPLC combined with FT-MS could be used as a high efficient method for the identification of the protein in human milk samples.
基金supported by the Young Talent Fund of University Association for Science and Technoloqy in Shaanxi, China (No. 20160222)The PetroChina Innovation Foundation (No. 2016D-5007-0404)the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2017JQ2034)
文摘The nitrogen-containing compounds in Changqing crude oil, its atmospheric residue(AR), and vacuum reside(VR) were characterized by negative and positive ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). The heteroatom compounds(N_1, N_2, N_1O_1, O_1, and O_2 class species) could be identified by the negative ESI analysis, while the positive mode could only detect the N_1, N_2, and N_1O_1 class species. Among them, the N_1 class species were found to be predominant in crude oil, as confirmed by either negative or positive ESI analyses,which were similar in composition to AR and VR. These compounds with higher abundance were characterized by double bond equivalent(DBE) values and carbon numbers. The composition of these compounds in crude oil and its AR as well as VR was correlated with their different boiling range, DBE values and carbon numbers. The negative ESI analysis showed that the abundant N_1 class species in crude oil and AR were centered at a DBE value of 12, and these species were likely benzocarbazoles, while the N_1 class species with the DBE value ranging from 13 to 16 having more complicated molecular structures were dominant in VR. And the positive ESI analysis gave the information of the abundant N_1 class species in crude oil, AR, and VR having the DBE values in the range of 10, 9―11, and 10―16, respectively, which were likely the compounds with the core of quinoline and benzoquinoline. The analysis confirmed that the distillation process in refinery preferentially removed the low DBE value and low molecular N-class species and brought them into the light and medium distillates, while those N-class species having a high molecular condensation in the molecules with large carbon number remained in the residual oil and could continually affect the downstream oil refining process.