This study synthesised a zincic salt(ZS)as a depressant for marmatite-galena separation.The effect of ZS on the flotation of marmatite and galena was investigated through micro-flotation tests.88.89%of the galena was ...This study synthesised a zincic salt(ZS)as a depressant for marmatite-galena separation.The effect of ZS on the flotation of marmatite and galena was investigated through micro-flotation tests.88.89%of the galena was recovered and 83.39%of the marmatite was depressed with ZS dosage of 750 mg·L^(−1)at pH=4.The depression mechanism of ZS on marmatite was investigated by a variety of techniques,including adsorption measurements,Fourier transform infrared(FTIR),X-ray photoelectron spectroscopic(XPS)analysis,and time of flight secondary ion mass spectrometry(ToF-SIMS).Results of adsorption tests and FTIR reveal that ZS adsorbed on marmatite surface and impeded the subsequent adsorption of butyl xanthate(BX).The results of XPS and ToF-SIMS indicate that the ZnO_(2)^(3-)released by ZS could be chemisorbed on the marmatite surface and depress marmatite flotation.展开更多
自Benninghoven。A 提出静态二次离子质谱(Static Secondary Ion Mass Spectrometry或SSIMS)方法以来,它就成为一种极灵敏的表面分析技术。近年来,SSIMS技术在多相催化研究中的应用日益广泛。我们曾成功地用SSIMS表征过MoO_3-NiO-P_2O_5...自Benninghoven。A 提出静态二次离子质谱(Static Secondary Ion Mass Spectrometry或SSIMS)方法以来,它就成为一种极灵敏的表面分析技术。近年来,SSIMS技术在多相催化研究中的应用日益广泛。我们曾成功地用SSIMS表征过MoO_3-NiO-P_2O_5/γ-Al_2O_3催化剂的表面结构层次.本工作中,我们应用SSIMS,并结合XPS对新型催化剂MoO_-CoO/TiO_2-Al_2O_3的表面结构层次和表面状态作了研究.展开更多
The authors applied the Secondary Ion Mass Spectrometry (SIMS) technique to the analysis of compositions and structures of vitrinites fusinites, fusinites bitumens and graptolites in the hydrocarbon source rocks with ...The authors applied the Secondary Ion Mass Spectrometry (SIMS) technique to the analysis of compositions and structures of vitrinites fusinites, fusinites bitumens and graptolites in the hydrocarbon source rocks with different maturities dscribed their SIMS spectral characteristics and found that different macerals have differnt spectra which, reflected the compositional and structural differences of macerals. Moreover, the change bod of parameter CH2+/CH3+ can be used for the evaluation of thermal evolution regularity of macerals in the hydrocarbon source rocks The study results show that the SIMS technique is a powerful means for microara analysis of macerals in coals and source rocks. It is certain that the study level of macerals can be raised by detailed study of SIMS results of SIMS results of macerals.展开更多
The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology. and the “anchor state” of the membrane-hund protein on membrane is the key problem which it is difficult t...The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology. and the “anchor state” of the membrane-hund protein on membrane is the key problem which it is difficult to solve with traditional methotls. In the present work we first studied the “anchor state” of melittin on membrane using liquid secondary ion mass spectrometry (LSIMS) in combination with proteolysis by specific enzyme. The results show that the membrane-bound melittin molecules mainly take the conformation in which the axis of α-helix lies parallel to the membrane surface and the side containing Lys7, Lys2I and Arg22 faces the outside of the lipid membrane. This discovery is very significant to the studies of membrane insertion mechanism. The results also indicate that the combination of mass spectrometry technique with the proteolysis by specific enzyme has provided a very new and effective method for the studies of the membrane insertion mechanism.展开更多
Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify...Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify the proteolytic products of proteins, but also be used to research the dynamics of proteolytic reactions. The proteolysis of melittin by trypsin gave seven main peptide fragments: 1, AA 1 AA 7 ; 2, AA 1 AA 21 ;3, AA 1 AA 22 ; 4, AA 1 AA 23 ; 5, AA 1 AA 24 ; 6, AA 8 AA 21 ; 7, AA 8 AA 22 . The proteolysis of melittin with pepsin gave thirteen peptide fragments: 1, AA 1 AA 3; 2, AA 4 AA 6;3, AA 1 AA 4;4, AA 1 AA 5 ;5, AA 1 AA 6 ;6, AA 1 AA 8;7, AA 7 AA 13 ;8, AA 10 AA 13 ;9, AA 14 AA 16 ;10, AA 14 AA 26 ;11, AA 15 AA 26 ;12, AA 17 AA 26 ;13, AA 20 AA 26 .展开更多
In this study, thin films were produced by magnetron sputtering NC （nanocrystalline） specimens of titanium saturated in hydrogen and were evaluated by layer-by-layer SIMS （secondary ion mass spectrometry） and Rama...In this study, thin films were produced by magnetron sputtering NC （nanocrystalline） specimens of titanium saturated in hydrogen and were evaluated by layer-by-layer SIMS （secondary ion mass spectrometry） and Raman spectroscopy. Due to magnetron sputtering, the chemical composition of the films was non-homogeneous and was variable among layers. Moreover, in the deposition of specimens saturated with hydrogen, hydrogen diffused throughout the depth of the film; diffusion, however, was restricted to the area near the film-substrate interface, affecting less than 50% of the thickness of the film.展开更多
In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/...In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/composition. The determined rock type is roughly similar to palynofacies of Combaz , whereas it is "rock maceral facies (for coal viz. coal facies)" in strictly speaking. Therefore, it is necessary to use the organic ingredients classification proposed by the authors so that it can be used for both maceral analysis and environment research . This source rock classification not only shows sedimentology and diagenetic changes but also acquires organic matter type even if hydrocarbon potential derived from maceral’s geochemical parameters. So, it is considered as genetic classification. The "rock maceral facies" may be transformed to sedimentary organic facies , which is used as quantitative evaluation means if research being perfect.Now, there are many models in terms of structure either for coal or for kerogen. In our opinion, whatever coal or kerogen ought be polymer, then we follow Combaz’s thought and study structure of amorphous kerogens which are accordance with genetic mechanism showing biochemical and geochemical process perfectly. Here, we use the time of flight secondary ion mass spectrometry (TOFSIMS) to expand Combaz’s models from three to five. They are also models for coal.展开更多
The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of t...The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of the derivatives provide information on their linkage Positions and iso- merism of the individual monoscaccharide units.The results indicated that among the derivatives of the oligosaccharides analyzed,those with 1—4 and 1—6 linkages all presented the ion peaks at m/z 287,sometimes one more peak at m/z 449.Furthermore,a relationship was found between the linkage positions and the intensity orders of the derivative ions.Finally,the derivatives of the disaccharides with a galactose presented an intense ion peak at m/z 347,and those of oligosaccharides with 1—6 linkage to a galactose at terminal presented the ion at m/z 317.In the case of oligosaccharides with a fructose residue,characteristic ion of m/z 155 was produced.The conditions of stereoselective derivatizations and mass spectrometry were studied,in order to obtain a better reproducibility of the mass spectra.展开更多
基金financially supported by the National Natural Science Foundation of China(No.52274283)the Fundamental Research Funds for the Central Universities(No.2022JCCXHH09)+1 种基金the Yueqi Outstanding Scholar award of CUMTB,the Science and Technology Major Project of Ordos City-Iconic Innovation Team(No.202204)the National Key R&D Program of China(Nos.2022YFC2900065 and 2021YFC2902602).
文摘This study synthesised a zincic salt(ZS)as a depressant for marmatite-galena separation.The effect of ZS on the flotation of marmatite and galena was investigated through micro-flotation tests.88.89%of the galena was recovered and 83.39%of the marmatite was depressed with ZS dosage of 750 mg·L^(−1)at pH=4.The depression mechanism of ZS on marmatite was investigated by a variety of techniques,including adsorption measurements,Fourier transform infrared(FTIR),X-ray photoelectron spectroscopic(XPS)analysis,and time of flight secondary ion mass spectrometry(ToF-SIMS).Results of adsorption tests and FTIR reveal that ZS adsorbed on marmatite surface and impeded the subsequent adsorption of butyl xanthate(BX).The results of XPS and ToF-SIMS indicate that the ZnO_(2)^(3-)released by ZS could be chemisorbed on the marmatite surface and depress marmatite flotation.
文摘自Benninghoven。A 提出静态二次离子质谱(Static Secondary Ion Mass Spectrometry或SSIMS)方法以来,它就成为一种极灵敏的表面分析技术。近年来,SSIMS技术在多相催化研究中的应用日益广泛。我们曾成功地用SSIMS表征过MoO_3-NiO-P_2O_5/γ-Al_2O_3催化剂的表面结构层次.本工作中,我们应用SSIMS,并结合XPS对新型催化剂MoO_-CoO/TiO_2-Al_2O_3的表面结构层次和表面状态作了研究.
文摘The authors applied the Secondary Ion Mass Spectrometry (SIMS) technique to the analysis of compositions and structures of vitrinites fusinites, fusinites bitumens and graptolites in the hydrocarbon source rocks with different maturities dscribed their SIMS spectral characteristics and found that different macerals have differnt spectra which, reflected the compositional and structural differences of macerals. Moreover, the change bod of parameter CH2+/CH3+ can be used for the evaluation of thermal evolution regularity of macerals in the hydrocarbon source rocks The study results show that the SIMS technique is a powerful means for microara analysis of macerals in coals and source rocks. It is certain that the study level of macerals can be raised by detailed study of SIMS results of SIMS results of macerals.
文摘The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology. and the “anchor state” of the membrane-hund protein on membrane is the key problem which it is difficult to solve with traditional methotls. In the present work we first studied the “anchor state” of melittin on membrane using liquid secondary ion mass spectrometry (LSIMS) in combination with proteolysis by specific enzyme. The results show that the membrane-bound melittin molecules mainly take the conformation in which the axis of α-helix lies parallel to the membrane surface and the side containing Lys7, Lys2I and Arg22 faces the outside of the lipid membrane. This discovery is very significant to the studies of membrane insertion mechanism. The results also indicate that the combination of mass spectrometry technique with the proteolysis by specific enzyme has provided a very new and effective method for the studies of the membrane insertion mechanism.
文摘Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify the proteolytic products of proteins, but also be used to research the dynamics of proteolytic reactions. The proteolysis of melittin by trypsin gave seven main peptide fragments: 1, AA 1 AA 7 ; 2, AA 1 AA 21 ;3, AA 1 AA 22 ; 4, AA 1 AA 23 ; 5, AA 1 AA 24 ; 6, AA 8 AA 21 ; 7, AA 8 AA 22 . The proteolysis of melittin with pepsin gave thirteen peptide fragments: 1, AA 1 AA 3; 2, AA 4 AA 6;3, AA 1 AA 4;4, AA 1 AA 5 ;5, AA 1 AA 6 ;6, AA 1 AA 8;7, AA 7 AA 13 ;8, AA 10 AA 13 ;9, AA 14 AA 16 ;10, AA 14 AA 26 ;11, AA 15 AA 26 ;12, AA 17 AA 26 ;13, AA 20 AA 26 .
文摘In this study, thin films were produced by magnetron sputtering NC （nanocrystalline） specimens of titanium saturated in hydrogen and were evaluated by layer-by-layer SIMS （secondary ion mass spectrometry） and Raman spectroscopy. Due to magnetron sputtering, the chemical composition of the films was non-homogeneous and was variable among layers. Moreover, in the deposition of specimens saturated with hydrogen, hydrogen diffused throughout the depth of the film; diffusion, however, was restricted to the area near the film-substrate interface, affecting less than 50% of the thickness of the film.
基金National Natural Science Foundation of China(4 9672 13 1)
文摘In accordance with the confusion on classification of source rocks, the authors raised a source rock classification for its enriched and dispersed organic matter types based on both Alpern’s idea and maceral genesis/composition. The determined rock type is roughly similar to palynofacies of Combaz , whereas it is "rock maceral facies (for coal viz. coal facies)" in strictly speaking. Therefore, it is necessary to use the organic ingredients classification proposed by the authors so that it can be used for both maceral analysis and environment research . This source rock classification not only shows sedimentology and diagenetic changes but also acquires organic matter type even if hydrocarbon potential derived from maceral’s geochemical parameters. So, it is considered as genetic classification. The "rock maceral facies" may be transformed to sedimentary organic facies , which is used as quantitative evaluation means if research being perfect.Now, there are many models in terms of structure either for coal or for kerogen. In our opinion, whatever coal or kerogen ought be polymer, then we follow Combaz’s thought and study structure of amorphous kerogens which are accordance with genetic mechanism showing biochemical and geochemical process perfectly. Here, we use the time of flight secondary ion mass spectrometry (TOFSIMS) to expand Combaz’s models from three to five. They are also models for coal.
基金Project supported by the National Natural Science Foundation of China
文摘The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of the derivatives provide information on their linkage Positions and iso- merism of the individual monoscaccharide units.The results indicated that among the derivatives of the oligosaccharides analyzed,those with 1—4 and 1—6 linkages all presented the ion peaks at m/z 287,sometimes one more peak at m/z 449.Furthermore,a relationship was found between the linkage positions and the intensity orders of the derivative ions.Finally,the derivatives of the disaccharides with a galactose presented an intense ion peak at m/z 347,and those of oligosaccharides with 1—6 linkage to a galactose at terminal presented the ion at m/z 317.In the case of oligosaccharides with a fructose residue,characteristic ion of m/z 155 was produced.The conditions of stereoselective derivatizations and mass spectrometry were studied,in order to obtain a better reproducibility of the mass spectra.
