The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Lu Yang - One of the best experts on this subject based on the ideXlab platform.
-
in situ sulfur isotopes δ 34 s and δ 33 s analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation mc icp ms
Analytica Chimica Acta, 2016Co-Authors: Jiali Fu, Zhaochu Hu, Wen Zhang, Lu Yang, Ming Li, Keqing Zong, Shenghong HuAbstract:Abstract The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N 2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum Makeup Gas flow when using Ar plasma only. The addition of 4–8 ml min −1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum Makeup Gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N 2 = 4 ml min −1 ). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d 90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis should be less than 10 μm. Under the selected optimized analytical conditions, excellent agreements between the determined values and the reference values were achieved for the IAEA-S series standard reference materials and a set of six well-characterized, isotopic homogeneous sulfide standards (PPP-1, MoS 2 , MASS-1, P-GBW07267, P-GBW07268, P-GBW07270), validating the capability of the developed method for providing high-quality in situ S isotope data in sulfides and elemental sulfur.
-
improved in situ hf isotope ratio analysis of zircon using newly designed x skimmer cone and jet sample cone in combination with the addition of nitrogen by laser ablation multiple collector icp ms
Journal of Analytical Atomic Spectrometry, 2012Co-Authors: Yongsheng Liu, Haihong Chen, Shan Gao, Wen Zhang, Keqing Zong, Wengui Liu, Xirun Tong, Lin Lin, Lian Zhou, Lu YangAbstract:The effect of three different cone combinations on the performance of laser ablation MC-ICP-MS (Neptune plus) for the in situ Hf isotope analysis of zircon were investigated. The signal sensitivities of Hf, Yb and Lu were improved by a factor of 1.4 and 2.5, respectively, with using the X skimmer cone + standard sampler cone and the X skimmer cone + Jet sample cone compared to the standard arrangement (H skimmer cone + standard sample cone). However, when using the high-sensitivity Jet sample cone, the instrumental mass fractionation for hafnium displayed a large non-linear component that could not be corrected using the normal mass fractionation laws. The magnitude of this non-linear mass fractionation was strongly related to the central Gas flow rate. The in situ Hf isotope analysis of zircon standards 91500 and Mud Tank using the Jet cone displayed large deviations (410–470 ppm) at the optimum central Gas flow rate for Hf, which seriously deteriorated the performance of the Jet cone. The addition of 4 ml min−1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to not only increase the sensitivity of Hf by a factor of 2.1, but also suppress this non-linear mass fractionation. The determined Yb/Hf and Lu/Hf ratios at their corresponding optimum Makeup Gas flow rates for Hf intensity were found to be reduced by factors of 2 and 1.3 in the presence of nitrogen, respectively, which would benefit the accurate in situ determination of Hf isotopes in high-content Yb and Lu samples. Compared to the standard arrangement, the corresponding precision (2σ) of 176Hf/177Hf for single spot analysis of zircon standard 91500 was improved from 224 ppm to 50 ppm by using the newly designed X-skimmer cone and Jet sample cone in combination with the nitrogen addition technique. The determined 176Hf/177Hf ratios are in excellent agreement with published values in five reference zircon standards (91500, GJ-1, Mud Tank, Penglai and Plesovice). Our first Hf isotopic results from zircon standard M257 (0.281544 ± 0.000018; 2SD, n = 151) showed that it was fairly homogeneous in Hf isotopes. These results clearly demonstrate that the present analytical method has the potential to become an important tool for the pursuit of high-quality in situ Hf isotope data for zircons.
Shenghong Hu - One of the best experts on this subject based on the ideXlab platform.
-
in situ sulfur isotopes δ 34 s and δ 33 s analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation mc icp ms
Analytica Chimica Acta, 2016Co-Authors: Jiali Fu, Zhaochu Hu, Wen Zhang, Lu Yang, Ming Li, Keqing Zong, Shenghong HuAbstract:Abstract The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N 2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum Makeup Gas flow when using Ar plasma only. The addition of 4–8 ml min −1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum Makeup Gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N 2 = 4 ml min −1 ). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d 90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis should be less than 10 μm. Under the selected optimized analytical conditions, excellent agreements between the determined values and the reference values were achieved for the IAEA-S series standard reference materials and a set of six well-characterized, isotopic homogeneous sulfide standards (PPP-1, MoS 2 , MASS-1, P-GBW07267, P-GBW07268, P-GBW07270), validating the capability of the developed method for providing high-quality in situ S isotope data in sulfides and elemental sulfur.
-
signal enhancement in laser ablation icp ms by addition of nitrogen in the central channel Gas
Journal of Analytical Atomic Spectrometry, 2008Co-Authors: Zhaochu Hu, Yongsheng Liu, Shenghong Hu, Haihong Chen, Shan Gao, Honglin YuanAbstract:The effects of adding nitrogen to the central Gas flow (Ar + He) of an Ar plasma in laser ablation inductively coupled plasma mass spectrometry are presented. The optimum central Gas flow rate was found to be negatively correlated with the N2 Gas flow rate. The addition of 5–10 ml min−1nitrogen to the central channel Gas in LA-ICP-MS increases the sensitivity for most of the 65 investigated elements by a factor of 2–3. The degree of enhancement depends, to some extent, on the 1st ionization energy. Another important advantage of N2 mixed Gas plasma for LA-ICP-MS is that the oxide ratios (ThO+/Th+) are significantly reduced (one order of magnitude). The hydride ratio (ArH+/Ar+) is also reduced up to a factor of 3, whereas the doubly charged ion ratio (Ca2+/Ca+) is increased. The background signals at masses 29, 31, 42, 51, 52 and 55 are significantly increased due to the nitrogen based polyatomic interferences. Compared to the spatial profiles of the ion distributions in the normal mode (without nitrogen), the addition of 5 ml min−1nitrogen leads to significant wider axial profiles and more uniform distribution of ions with different physical and chemical properties. Our results also show that the Makeup Gas flow (central channel Gas) rate has a significant effect on the ion distribution of elements with different physical and chemical properties. A very consistent increase of argon signal by the addition of nitrogen (5 ml min−1) corroborates better energy transfer effect of nitrogen in the plasma.
Zhaochu Hu - One of the best experts on this subject based on the ideXlab platform.
-
in situ sulfur isotopes δ 34 s and δ 33 s analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation mc icp ms
Analytica Chimica Acta, 2016Co-Authors: Jiali Fu, Zhaochu Hu, Wen Zhang, Lu Yang, Ming Li, Keqing Zong, Shenghong HuAbstract:Abstract The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N 2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum Makeup Gas flow when using Ar plasma only. The addition of 4–8 ml min −1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum Makeup Gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N 2 = 4 ml min −1 ). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d 90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis should be less than 10 μm. Under the selected optimized analytical conditions, excellent agreements between the determined values and the reference values were achieved for the IAEA-S series standard reference materials and a set of six well-characterized, isotopic homogeneous sulfide standards (PPP-1, MoS 2 , MASS-1, P-GBW07267, P-GBW07268, P-GBW07270), validating the capability of the developed method for providing high-quality in situ S isotope data in sulfides and elemental sulfur.
-
signal enhancement in laser ablation icp ms by addition of nitrogen in the central channel Gas
Journal of Analytical Atomic Spectrometry, 2008Co-Authors: Zhaochu Hu, Yongsheng Liu, Shenghong Hu, Haihong Chen, Shan Gao, Honglin YuanAbstract:The effects of adding nitrogen to the central Gas flow (Ar + He) of an Ar plasma in laser ablation inductively coupled plasma mass spectrometry are presented. The optimum central Gas flow rate was found to be negatively correlated with the N2 Gas flow rate. The addition of 5–10 ml min−1nitrogen to the central channel Gas in LA-ICP-MS increases the sensitivity for most of the 65 investigated elements by a factor of 2–3. The degree of enhancement depends, to some extent, on the 1st ionization energy. Another important advantage of N2 mixed Gas plasma for LA-ICP-MS is that the oxide ratios (ThO+/Th+) are significantly reduced (one order of magnitude). The hydride ratio (ArH+/Ar+) is also reduced up to a factor of 3, whereas the doubly charged ion ratio (Ca2+/Ca+) is increased. The background signals at masses 29, 31, 42, 51, 52 and 55 are significantly increased due to the nitrogen based polyatomic interferences. Compared to the spatial profiles of the ion distributions in the normal mode (without nitrogen), the addition of 5 ml min−1nitrogen leads to significant wider axial profiles and more uniform distribution of ions with different physical and chemical properties. Our results also show that the Makeup Gas flow (central channel Gas) rate has a significant effect on the ion distribution of elements with different physical and chemical properties. A very consistent increase of argon signal by the addition of nitrogen (5 ml min−1) corroborates better energy transfer effect of nitrogen in the plasma.
Wen Zhang - One of the best experts on this subject based on the ideXlab platform.
-
in situ sulfur isotopes δ 34 s and δ 33 s analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation mc icp ms
Analytica Chimica Acta, 2016Co-Authors: Jiali Fu, Zhaochu Hu, Wen Zhang, Lu Yang, Ming Li, Keqing Zong, Shenghong HuAbstract:Abstract The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N 2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum Makeup Gas flow when using Ar plasma only. The addition of 4–8 ml min −1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum Makeup Gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N 2 = 4 ml min −1 ). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d 90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis should be less than 10 μm. Under the selected optimized analytical conditions, excellent agreements between the determined values and the reference values were achieved for the IAEA-S series standard reference materials and a set of six well-characterized, isotopic homogeneous sulfide standards (PPP-1, MoS 2 , MASS-1, P-GBW07267, P-GBW07268, P-GBW07270), validating the capability of the developed method for providing high-quality in situ S isotope data in sulfides and elemental sulfur.
-
improved in situ hf isotope ratio analysis of zircon using newly designed x skimmer cone and jet sample cone in combination with the addition of nitrogen by laser ablation multiple collector icp ms
Journal of Analytical Atomic Spectrometry, 2012Co-Authors: Yongsheng Liu, Haihong Chen, Shan Gao, Wen Zhang, Keqing Zong, Wengui Liu, Xirun Tong, Lin Lin, Lian Zhou, Lu YangAbstract:The effect of three different cone combinations on the performance of laser ablation MC-ICP-MS (Neptune plus) for the in situ Hf isotope analysis of zircon were investigated. The signal sensitivities of Hf, Yb and Lu were improved by a factor of 1.4 and 2.5, respectively, with using the X skimmer cone + standard sampler cone and the X skimmer cone + Jet sample cone compared to the standard arrangement (H skimmer cone + standard sample cone). However, when using the high-sensitivity Jet sample cone, the instrumental mass fractionation for hafnium displayed a large non-linear component that could not be corrected using the normal mass fractionation laws. The magnitude of this non-linear mass fractionation was strongly related to the central Gas flow rate. The in situ Hf isotope analysis of zircon standards 91500 and Mud Tank using the Jet cone displayed large deviations (410–470 ppm) at the optimum central Gas flow rate for Hf, which seriously deteriorated the performance of the Jet cone. The addition of 4 ml min−1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to not only increase the sensitivity of Hf by a factor of 2.1, but also suppress this non-linear mass fractionation. The determined Yb/Hf and Lu/Hf ratios at their corresponding optimum Makeup Gas flow rates for Hf intensity were found to be reduced by factors of 2 and 1.3 in the presence of nitrogen, respectively, which would benefit the accurate in situ determination of Hf isotopes in high-content Yb and Lu samples. Compared to the standard arrangement, the corresponding precision (2σ) of 176Hf/177Hf for single spot analysis of zircon standard 91500 was improved from 224 ppm to 50 ppm by using the newly designed X-skimmer cone and Jet sample cone in combination with the nitrogen addition technique. The determined 176Hf/177Hf ratios are in excellent agreement with published values in five reference zircon standards (91500, GJ-1, Mud Tank, Penglai and Plesovice). Our first Hf isotopic results from zircon standard M257 (0.281544 ± 0.000018; 2SD, n = 151) showed that it was fairly homogeneous in Hf isotopes. These results clearly demonstrate that the present analytical method has the potential to become an important tool for the pursuit of high-quality in situ Hf isotope data for zircons.
Keqing Zong - One of the best experts on this subject based on the ideXlab platform.
-
in situ sulfur isotopes δ 34 s and δ 33 s analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation mc icp ms
Analytica Chimica Acta, 2016Co-Authors: Jiali Fu, Zhaochu Hu, Wen Zhang, Lu Yang, Ming Li, Keqing Zong, Shenghong HuAbstract:Abstract The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N 2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum Makeup Gas flow when using Ar plasma only. The addition of 4–8 ml min −1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum Makeup Gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N 2 = 4 ml min −1 ). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d 90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis should be less than 10 μm. Under the selected optimized analytical conditions, excellent agreements between the determined values and the reference values were achieved for the IAEA-S series standard reference materials and a set of six well-characterized, isotopic homogeneous sulfide standards (PPP-1, MoS 2 , MASS-1, P-GBW07267, P-GBW07268, P-GBW07270), validating the capability of the developed method for providing high-quality in situ S isotope data in sulfides and elemental sulfur.
-
improved in situ hf isotope ratio analysis of zircon using newly designed x skimmer cone and jet sample cone in combination with the addition of nitrogen by laser ablation multiple collector icp ms
Journal of Analytical Atomic Spectrometry, 2012Co-Authors: Yongsheng Liu, Haihong Chen, Shan Gao, Wen Zhang, Keqing Zong, Wengui Liu, Xirun Tong, Lin Lin, Lian Zhou, Lu YangAbstract:The effect of three different cone combinations on the performance of laser ablation MC-ICP-MS (Neptune plus) for the in situ Hf isotope analysis of zircon were investigated. The signal sensitivities of Hf, Yb and Lu were improved by a factor of 1.4 and 2.5, respectively, with using the X skimmer cone + standard sampler cone and the X skimmer cone + Jet sample cone compared to the standard arrangement (H skimmer cone + standard sample cone). However, when using the high-sensitivity Jet sample cone, the instrumental mass fractionation for hafnium displayed a large non-linear component that could not be corrected using the normal mass fractionation laws. The magnitude of this non-linear mass fractionation was strongly related to the central Gas flow rate. The in situ Hf isotope analysis of zircon standards 91500 and Mud Tank using the Jet cone displayed large deviations (410–470 ppm) at the optimum central Gas flow rate for Hf, which seriously deteriorated the performance of the Jet cone. The addition of 4 ml min−1 nitrogen to the central Gas flow in laser ablation MC-ICP-MS was found to not only increase the sensitivity of Hf by a factor of 2.1, but also suppress this non-linear mass fractionation. The determined Yb/Hf and Lu/Hf ratios at their corresponding optimum Makeup Gas flow rates for Hf intensity were found to be reduced by factors of 2 and 1.3 in the presence of nitrogen, respectively, which would benefit the accurate in situ determination of Hf isotopes in high-content Yb and Lu samples. Compared to the standard arrangement, the corresponding precision (2σ) of 176Hf/177Hf for single spot analysis of zircon standard 91500 was improved from 224 ppm to 50 ppm by using the newly designed X-skimmer cone and Jet sample cone in combination with the nitrogen addition technique. The determined 176Hf/177Hf ratios are in excellent agreement with published values in five reference zircon standards (91500, GJ-1, Mud Tank, Penglai and Plesovice). Our first Hf isotopic results from zircon standard M257 (0.281544 ± 0.000018; 2SD, n = 151) showed that it was fairly homogeneous in Hf isotopes. These results clearly demonstrate that the present analytical method has the potential to become an important tool for the pursuit of high-quality in situ Hf isotope data for zircons.
