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Positive carbon isotope excursions:global correlation and genesis in the Middle-Upper Ordovician in the northern Tarim Basin,Northwest China

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Petroleum Science 2016年第2期13卷 192-203页

作者： Cun-Ge liu li-Xin Qi yong-li liu Ming-Xia Luo Xiao-Ming Shao Peng Luo Zhi-li Zhang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Northwest Oilfield Company China Petroleum & Chemical Corporation Institute of Petroleum Exploration and Development Petroleum & Chemical Corporation

Stable carbon isotope ratio （δ13Ccarb） analysis has been widely applied to the study of the inter-conti- nental or global marine carbonate correlation. Large-scale Cambrian-Ordovician carbonate platforms were developed in the Tarim Basin. But research on fluctuation character- istics and global correlation of δ13Ccarb is still weak. Based on conodont biostratigraphy and whole-rock δ13Ccarb data in the Tahe oil-gas field of the northern Tarim Basin, the global correlation and genesis of positive carbon isotope excursions in the Darriwilian--Early Katian was exam- ined. Three positive excursions were identified in the Tahe oil-gas field including the middle Darriwilian carbon iso- tope excursion （MDICE）, the Guttenberg carbon isotope excursion （GICE）, and a positive excursion within the Pygodus anserinus conodont zone which is named the Early Sandbian carbon isotope excursion （ESICE） in this paper. Furthermore, these positive excursions had no direct relation with sea level fluctuations. MDICE and GICE could be globally correlated. The Middle-Upper Ordovi- cian Saergan Formation source rocks of the Kalpin outcrops were in accordance with the geological time of MDICE and ESICE. GICE had close relationship with the source rock of the lianglitag Formation in the *** organic carbon burial was an important factor controlling the genesis of these positive excursions.

关键词： Tarim Basin Tahe oil-gas field - Middle-Upper Ordovician Carbon isotope Darriwilian Sandbian Katian source rock

Effect of Al_(2)O_(3)fiber on twin intersections-induced dynamic recrystallization in fine-grained TiAl matrix composite

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Journal of Materials Science & Technology 2024年第5期172卷 1-14页

作者： Yaofeng Luo Yan Wang li Wang Bin liu yong liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl ***,the underlying DRX mechanism remains poorly *** this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction *** addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first *** re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic *** origin of the twin intersection and TDRX for the composite was *** stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin *** high stored strain energy at the regions of twins and twin intersections provided the driving force for *** accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)*** present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.

关键词： TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization

Engineering single-atom Mn on nitrogen-doped carbon to regulate lithium-peroxide reaction kinetics for rechargeable lithium-oxygen batteries

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Journal of Energy Chemistry 2024年第7期94卷 199-207页

作者： Yaling Huang yong liu Yang liu Chenyang Zhang Wenzhang li Jie li School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083HunanChina School of Minerals Processing and Bioengineering Central South UniversityChangsha 4003HunanChina

Precision engineering of catalytic sites to guide more favorable pathways for li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of li-O_(2) *** this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N_(4) moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of li-O_(2) *** porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of li_(2)O_(2).The li-O_(2) batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g^(-1) at 100 mAg^(-1)),and superior cycle stability(>100 cycles at 200 mA g^(-1))compared with the Mn NPs-NC and *** functional theory(DFT)cal-culations reveal that the construction of Mn-N_(4) moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(liO_(2) and li_(2)O_(2)).The initial nucleation of li_(2)O_(2) on Mn SAs-NC favors the O_(2)-→liO_(2)→li_(2)O_(2) surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N_(4) moiety effectively facilitates the li_(2)O_(2) nucleation and enables its reversible *** work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for li-O_(2)batteries.

关键词： Single-atom Mn MOFs-oriented architecture Rechargeable li-O_(2)battery N-doped carbon Density functional theory calculation

Oil charging history and pathways of the Ordovician carbonate reservoir in the Tuoputai region,Tarim Basin,NW China

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Petroleum Science 2017年第4期14卷 662-675页

作者： Rong-Hui Fang Mei-Jun li Hai-Tao Lü T.-G.Wang Yuan Yuan yong-li liu Zhi-yong Ni State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing 102249China Exploration and Development Research Institute Northwest Oilfield Branch CorporationSINOPECUrumqi 830011XinjiangChina Research Institute of Shaanxi Yanchang Petroleum(Group)Co.Ltd Xi'an 710075ShaanxiChina

Geochemical analysis of 64 oils sampled from an Ordovician carbonate reservoir in the Tuoputai region was undertaken to study the composition of molecular markers. All the oils have similar geochemical characteristics and belong to a single oil family. They are presumed to derive from the same source kitchen and have similar oil charging history. A histogram of homogenization temperatures(Th) of aqueous inclusions in reservoir rocks shows a bimodal distribution pattern, indicating that the Ordovician reservoir has been charged twice. Coupling the measured Th(°C) with the burial and geothermal histories reconstructed using 1D basin modeling, we relate the homogenization temperature to the relevant geological ages: i.e.,425–412 and 9–4 Ma, corresponding to the Middle to Late Silurian and the Miocene to Pliocene, respectively. The oil filling orientation and pathways are traced using molecular indicators related to alkyldibenzothiophenes and benzo[b]naphthothiophenes. The oil charging orientation is from south to north generally. It can be predicted that the Ordovician reservoirs were sourced from a kitchen located to the south of the Tuoputai region, most probably between the Awati and Manjiaer Depressions. Traps located in the southern side of the Tuoputai region, along the oil charging pathways, should therefore be preferred oil exploration targets.

关键词： Oil population Oil charging events Fluid inclusion 1D numerical modeling Oil filling pathway

Seeing measurements for the Guoshoujing Telescope (LAMOST) site with DIMM

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Research in Astronomy and Astrophysics 2010年第10期10卷 1061-1070页

作者： li-yong liu yong-Qiang Yao Yi-Ping Wang Jiang-Long Ma Bo-liang He Hong-Shuai Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We present seeing measurements of the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope- LAMOST） site at Xinglong station during the period from 2007 March 12 to April 25. The measurements were carried out with the Differential Image Motion Monitor （DIMM）, and a total of 9259 data sets was obtained. The median seeing was measured to be 1.1″, with 25% being better than 0.8″and 75% better than 1.5″. The experiment shows that the DIMM exposure time has significant effects on the results of seeing measurements. An SBIG Polaris seeing monitor, which had been planned to be installed on the LAMOST site for long-term monitoring, was also employed during the DIMM observations. The results show that the SBIG seeing monitor is easily affected by gusty wind, resulting in larger seeing values. Considering the previous seeing measurements at Xinglong station over the last 15 yr, we conclude that an acceptable seeing condition at Xinglong station is around 1″-2″.

关键词： techniques atmospheric turbulence seeing -- instrumentation DIMM -- site testing LAMOST

Grain Composition and Erosive Equilibrium of Debris Flows

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Journal of Mountain Science 2007年第1期4卷 71-76页

作者： li yong liu Jingling CHEN Xiaoqing WEI Fangqiang Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences ＆ Ministry of Water Conseruancy Chengdu 610041

Debris flows consist of grains of various sizes ranging from 10^(-6) m ～1 m. Field observations in the Jiangjia Gully (JJG) and other sites throughout China indicate that the grain size distribution of sediment in debris flows can be characterized by an exponential function fit to the cumulative distribution. The exponent value for the function varies by location and may be useful in distinguishing between debris flows from different valleys. For example, minimum values and ranges of the exponent are associated with the high frequency of debris flows in the JJG. Furthermore, the distribution presents piecewise fractality (i.e. scaling laws hold in various ranges of the grain size) and we propose that the fractal structure determines the matrix and that the fractal dimension plays a crucial role in material exchange between a debris flow and the substrate it flows over. Finally, the empirical data support an exponential relation between grain composition and non-dimensional shear stress for the critical state of the channel. Overall we propose a material-determinism approach to studying debris flows which contrasts with the enviro-determinism that has dominated much recent work in this field.

关键词： Grain composition fractal erosion equilibrium debris flow

Quantitative energy-dispersive X-ray fluorescence analysis for unknown samples using full-spectrum least-squares regression

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Nuclear Science and Techniques 2019年第3期30卷 149-159页

作者： yong-li liu Qing-Xian Zhang Jian Zhang Hai-Tao Bai liang-Quan Ge The College of Applied Nuclear Technology and Automation Engineering Chengdu University of Technology

The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid *** on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the Gi factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of lg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.

关键词： Energy-dispersive X-ray fluorescence analysis Full-spectrum least-squares method Effective atomic number Mass attenuation coefficient Fundamental parameter method

Analytical and Experimental Research on Wave Scattering by an Open-Type Rectangular Breakwater with Horizontal Perforated Plates

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Journal of Ocean University of China 2024年第5期23卷 1185-1201页

作者： HE Shuyue liu yong li Huajun Fisheries College Ocean University of China Shandong Province Key Laboratory of Ocean Engineering Ocean University of China

This study proposes a novel open-type rectangular breakwater combined with horizontal perforated plates on both sides to enhance the sheltering effect of the rectangular box-type breakwaters against longer waves. The hydrodynamic characteristics of this breakwater are analyzed through analytical potential solutions and experimental tests. The quadratic pressure drop conditions are exerted on the horizontal perforated plates to facilitate assessing the effect of wave height on the dissipated wave energy of breakwater through the analytical solution. The hydrodynamic quantities of the breakwater, including the reflection, transmission, and energyloss coefficients, together with vertical and horizontal wave forces, are calculated using the velocity potential decomposition method as well as an iterative algorithm. Furthermore, the reflection and transmission coefficients of the breakwater are measured by conducting experimental tests at various wave periods, wave heights, and both porosities and widths of the horizontal perforated plates. The analytical predicted results demonstrate good agreement with the iterative boundary element method solution and measured data. The influences of variable incident waves and structure parameters on the hydrodynamic characteristics of the breakwater are investigated through further calculations based on analytical solutions. Results indicate that horizontal perforated plates placed on the water surface for both sides of the rectangular breakwater can enhance the wave dissipation ability of the breakwater while effectively decreasing the transmission and reflection coefficients.

关键词： analytical solution experimental test horizontal perforated plates hydrodynamic characteristics rectangular breakwater

Impact of Mo/Ni alloying on microstructural modulation and low-temperature toughness of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1746-1762页

作者： Wei liu Hong-li Zhao Bing-xing Wang yong Tian State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

The high-strength low-alloy steel plates with varying Ni/Mo contents were manufactured using the thermos-mechanical control *** investigation was conducted to explore the effect of Ni/Mo microalloying on microstructure evolution and mechanical properties of the *** results revealed that the increase in Ni content from 1 to 2 wt.%reduced the transition temperature of ferrite and the growth range of ferritic grain was narrowed,which promoted grain *** optimized combination of grain size,high-angle grain boundaries(HAGBs),and martensite-austenite(M-A)islands parameter contributed to the excellent impact toughness of S1 steel at-100℃(impact absorbed energy of 218.2 J at-100℃).As the Mo increases from 0 to 2 wt.%,the matrix structure changes from multiphase structure to granular bainite,which increases the average effective grain size to~4.62 pm and reduces HAGBs proportion to~36.22%.With these changes,the low-temperature impact toughness of S3 steel is *** addition,based on the analysis of the characteristics of crack propagation path,it was found that M-A islands with low content(~2.21%)and small size(~1.76 pm)significantly retarded crack propagation,and the fracture model of M-A islands with different morphologies was further ***,correlation between behaviour of delamination and toughness was further analysed by observing delamination size and impact energy parameters.

关键词： High-strength low-alloy steel Microstructural regulation Ni addition Mo addition Crack propagation Low-temperature toughness