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加氢汽油中碳五和碳九测定的方法建立

广州化工 2024年第7期52卷 141-146页

作者：郑祥礼中国石油化工股份有限公司茂名分公司质检中心广东茂名525000

加氢装置中加氢汽油的C5-馏份及C9+馏份含量变化趋势是供生产调整的重要参数,所以,加氢装置产品加氢汽油需要分析其中的碳五和碳九馏分含量,结合生产控制指标,用于调节生产。目前,化验室现加氢汽油分析方法UOP-744-86仅能分析非芳烃含量... 详细信息

加氢装置中加氢汽油的C5-馏份及C9+馏份含量变化趋势是供生产调整的重要参数,所以,加氢装置产品加氢汽油需要分析其中的碳五和碳九馏分含量,结合生产控制指标,用于调节生产。目前,化验室现加氢汽油分析方法UOP-744-86仅能分析非芳烃含量,不能准确测定非芳烃中碳五馏份及碳九馏份的含量。进行调查分析,结合相关的实验数据,找出不能分离和测定C5馏份和C9馏份的原因主要是现有的方法使加氢汽油中C6~C8非芳烃峰组分密集,简单的条件选择也无法达到很好的分离效果。参考汽油全组份分析方法,把聚乙二醇-20M色谱柱改为实验室现有的PONA柱,并优化色谱操作条件:检测器温度240℃;进样口温度230℃;载气流速0.7 mL/min;分流比150∶1;进样量0.6μL;柱温程序:初始温度35℃,保留时间5 min,第一升温速率1℃/min升至100℃,保留时间0 min,第二升温速率10℃/min升至180℃,保留时间10 min。本文重点是结合生产需要,利用现有的仪器设备、材料,选择更加优化的色谱分析条件,建立了适于加氢汽油中碳五馏份及碳九馏份含量测定的分析方法。

关键词：加氢汽油碳五碳九 PONA分析

Reply to Comment by Steinberger on 'Will Earth's next supercontinent assemble through the closure of the Pacific Ocean?'

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National Science Review 2022年第12期9卷 71-72页

作者： Chuan Huang zheng-xiang li Nan Zhang Earth Dynamics Research Group The Institute for Geoscience Research (TIGeR) School of Earth and Planetary Sciences Curtin University Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University

Geo dynamic modeling of the super continent cycle crosses the fields of geology,geophysics and computational *** thus welcome the comment by *** from the numerical geodynamics point of view,which gives us the opportunity to clarify some of the concepts,explain further our model approach and necessary simplifications,and point out major ambiguities that require further work.

关键词： PLATE-TECTONICS EVOLUTION RHEOLOGY

Will Earth's next supercontinent assemble through the closure of the Pacific Ocean?

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National Science Review 2022年第12期9卷 73-81页

作者： Chuan Huang zheng-xiang li Nan Zhang Earth Dynamics Research Group The Institute for Geoscience Research(TIGeR) School of Earth and Planetary Sciences Curtin University Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University

Earth’s known super continents are believed to have formed in vastly different ways,with two endmembers being introversion and *** former involves the closure of the internal oceans formed during the break-up of the previous supercontinent,whereas the latter involves the closure of the previous external super ***,it is unclear what caused such diverging behavior of supercontinent cycles that involved first-order interaction between subducting tectonic plates and the *** we address this question through 4D geo dynamic modeling using realistic tectonic *** results show that the strength of the oceanic lithosphere plays a critical role in determining the assembly path of a *** found that high oceanic lithospheric strength leads to introversion assembly,whereas lower strength leads to extroversion assembly.A theoretically estimated reduction in oceanic crustal thickness,and thus its strength,during Earth’s secular cooling indicates that introversion was only possible for the Precambrian time when the oceanic lithosphere was stronger,thus predicting the assembling of the next supercontinent Amasia through the closure of the Pacific Ocean instead of the Indian-Atlantic *** work provides a new understanding of the secular evolution of plate tectonics and geodynamics as the Earth cooled.

关键词： yield stress oceanic lithosphere introversion extroversion supercontinent cycle

Testing the distance-duality relation with data from galaxy clusters and type Ia supernovae

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Research in Astronomy and Astrophysics 2011年第8期11卷 895-901页

作者： xiang-Yun Fu Pu-Xun Wu Hong-Wei Yu zheng-xiang li Institute of Physics Hunan University of Science and Technology Xiangtan 411201 China Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Department of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

We test the distance-duality （DD） relation by combining the angular diameter distance DA provided by two galaxy cluster samples compiled by De Filippis et al. （the elliptical β model） and Bonamente et al. （the spherical β model）, and the luminosity distance DL from Constitution and Union2 type Ia supernova （SNe Ia） datasets. To obtain DL associated with the observed DA at the same redshift, we smooth the noise of the SNe Ia in a model-independent way, obtain the evolutionary curve of DL and, finally, test the DD relation. We find that the elliptical β model, when compared with the SNe Ia from the Constitution compilation, is only consistent with the DD relation at the 3σ confidence level （CL）, while the spherical β model is incompatible with the DD relation at the 3σ CL. For the Union2 compilation, the De Filippis and Bonamente samples are marginally compatible with the validity of the DD relation at the 1σ and 2σ CLs, respectively.

关键词： galaxies: distances and redshifts -- galaxies: clusters: general -- super- novae: general

Determining H0 using a model-independent method

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Frontiers of physics 2017年第1期12卷 133-140页

作者： Pu-Xun Wu zheng-xiang li Hong-Wei Yu Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Center for High Energy Physics Peking University Beijing 100080 China Department of Astronomy Beijing Normal University Beijing 100875 China

By using type Ia supernovae （SNIa） to provide the luminosity distance （LD） directly, which depends on the value of the Hubble constant H0 = 100h km·s^-1· Mpc^-1, and the angular diameter distance from galaxy clusters or baryon acoustic oscillations （BAOs） to give the derived LD according to the distance duality relation, we propose a model-independent method to determine h from the fact that different observations should give the same LD at a given redshift. Combining the Sloan Digital Sky Survey II （SDSS-II） SNIa from the MLCS2k2 light curve fit and galaxy cluster data, we find that at the 1σ confidence level （CL）, h = 0.5867±0.0303 for the sample of the elliptical β model for galaxy clusters, and h = 0.6199± 0.0293 for that of the spherical β model. The former is smaller than the values from other observations, whereas the latter is consistent with the Planck result at the 2σ CL and agrees very well with the value reconstructed directly from the H（z） data. With the SDSS-II SNIa and BAO measurements, a tighter constraint, h = 0.6683 ± 0.0221, is obtained. For comparison, we also consider the Union 2.1 SNIa from the SALT2 light curve fitting. The results from the Union 2.1 SNIa are slightly larger than those from the SDSS-II SNIa, and the Union 2.1 SNIa ＋ BAOs give the tightest value. We find that the values from SNIa ＋ BAOs are quite consistent with those from the Planck and the BAOs, as well as the local measurement from Cepheids and very-low-redshift SNIa.

关键词： Hubble constant luminosity distance angular diameter distance

The dominant driving force for supercontinent breakup: Plume push or subduction retreat?

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Geoscience Frontiers 2018年第4期9卷 997-1007页

作者： Nan Zhang Zhuo Dang Chuan Huang zheng-xiang li Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Earth Dynamics Research Group ARC Center of Excellence for Core to Crust Fluid Systems(CCFS)and The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin University

Understanding the dominant force responsible for supercontinent breakup is crucial for establishing Earth＇s geodynamic evolution that includes supercontinent cycles and plate tectonics. Conventionally,two forces have been considered： the push by mantle plumes from the sub-continental mantle which is called the active force for breakup, and the dragging force from oceanic subduction retreat which is called the passive force for breakup. However, the relative importance of these two forces is unclear. Here we model the supercontinent breakup coupled with global mantle convection in order to address this question. Our global model features a spherical harmonic degree-2 structure, which includes a major subduction girdle and two large upwelling（superplume） systems. Based on this global mantle structure,we examine the distribution of extensional stress applied to the supercontinent by both subsupercontinent mantle upwellings and subduction retreat at the supercontinent peripheral. Our results show that：（1） at the center half of the supercontinent, plume push stress is ～3 times larger than the stress induced by subduction retreat;（2） an average hot anomaly of no higher than 50 K beneath the supercontinent can produce a push force strong enough to cause the initialization of supercontinent breakup;（3） the extensional stress induced by subduction retreat concentrates on a ～600 km wide zone on the boundary of the supercontinent, but has far less impact to the interior of the supercontinent. We therefore conclude that although circum-supercontinent subduction retreat assists supercontinent breakup, sub-supercontinent mantle upwelling is the essential force.

关键词： Supercontinent breakup Plume push Subduction retreat

Trial by fire:Testing the paleolongitude of Pangea of competing reference frames with the African LLSVP

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Geoscience Frontiers 2020年第4期11卷 1253-1256页

作者： Ross N.Mitchell Lei Wu J.Brendan Murphy zheng-xiang li State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijingChina Earth Dynamics Research Group The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin UniversityGPO Box U1987PerthWAAustralia Department of Earth Sciences St.Francis Xavier UniversityAntigonishNova ScotiaCanada

Paleogeography can be reconstructed using various crust-or mantle-based reference frames that make fundamentally different *** various reconstruction models differ significantly in continental paleolongitude,but it has been difficult to assess which models are more *** suggest here a "LLSVP test",where an assumed correlation between present-day large low velocity shear-wave provinces and the paleogeography of supercontinent Pangea at breakup ca.200 million years ago can be used to assess the relative accuracy of published *** correlations between continental paleolongitude and the African LLSVP are achieved with mantle-based reference frames(moving hotspots and true polar wander),whereas shallower crustbased reference frames are shown to be *** relative success of mantle-based frames,and thus the importance of the depth of reference frame,supports the notion that mantle convection is largely vertical compared to the horizontal plate motion of tectonics.

关键词： Palaeogeography Plate tectonics LLSVPs Reference frames

Solitary Wave Solutions of KP equation,Cylindrical KP Equation and Spherical KP Equation

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Communications in Theoretical Physics 2017年第2期67卷 207-211页

作者： xiang-zheng li Jin-liang Zhang Ming-liang Wang School of Mathematics and Statistcs Henan University of Science and Technology Luoyang 471023 China School of Mathematics and Statistcs Lanzhou University Lanzhou 730000 China

Three(2+1)-dimensional equations–KP equation, cylindrical KP equation and spherical KP equation, have been reduced to the same Kd V equation by different transformation of variables respectively. Since the single solitary wave solution and 2-solitary wave solution of the Kd V equation have been known already, substituting the solutions of the Kd V equation into the corresponding transformation of variables respectively, the single and 2-solitary wave solutions of the three(2+1)-dimensional equations can be obtained successfully.

关键词： 2-Solitary wave solution KP equation cylindrical KP equation spherical KP equation transformation of variables

Decoupling between Oxygen and Radiogenic Isotopes: Evidence for Generation of Juvenile Continental Crust by Partial Melting of Subducted Oceanic Crust

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Journal of Earth Science 2021年第5期32卷 1212-1225页

作者： Xuan-Ce Wang Qiuli li Simon A.Wilde zheng-xiang li Chaofeng li Kai Lei Shao-Jie li linlin li Manoj K.Pandit School of Earth Sciences Yunnan UniversityKunming 650500China School of Earth Science and Resources Chang1 an UniversityXi'an 710054China State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China ARC Centre of Excellence for Core to Crust Fluid Systems and The Institute for Geoscience Research Department of Applied GeologyCurtin UniversityPerth 6845Australia Department of Geology University of RajasthanJaipur 302004India

There is increasing evidence indicating that melts derived from subducted oceanic crust and sediments may have played a key role in building continental crust. This mechanism predicts that juvenile arc crust should have oxygen isotope characteristics ranging from mantle-like to supracrustal, but consistent mantle-like radiogenic(Nd-Hf) isotopic signatures. Here we present in-situ zircon U-Pb dating, Hf-O isotope analyses, and whole rock major-trace element and Nd isotope analyses of a granitoid from NW India. In-situ secondary ion mass spectrometry(SIMS) zircon U-Pb dating yields a weighted mean ^(207)Pb/^(206)Pb age of 873±6 Ma for the granitoid. It displays mantle-like zircon εHf(εHf(873 Ma)= +9.3 to +10.9) and whole-rock Nd(εNd(873 Ma)= +3.5) values but supracrustal δ^(18)O values, the latter mostly varying between 9‰ and 10‰. The calculated whole-rock δ^(18)O value of 11.3‰±0.6‰ matches well with those of hydrothermally-altered pillow lavas and sheeted dykes from ophiolites. The major and trace element composition of the granitoid is similar to petrological experimental melts derived from a mixture of MORB+sediments. Thus, the granitoid most likely represents the product of partial melting of the uppermost oceanic crust(MORB+sediments). We propose that the decoupling between Hf-Nd and O isotopes as observed in this granitoid can be used as a powerful tool for the identification of slab melting contributing to juvenile continental crustal growth. Such isotopic decoupling can also account for high δ^(18)O values observed in ancient juvenile continental crust, such as Archean tonalitetrondhjemite-granodiorite suites.

关键词： zircon Hf-Nd and O isotopes decoupling slab melting Neoproterozoic continental crustal growth