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High-frequency lacustrine sequence stratigraphy of clastic lakes: lessons from ancient successions

Journal of Palaeogeography 2024年第4期13卷 621-645页

作者： Carlos Zavala hua-qing liu Xiang-Bo Li Valentin Trobbiani Yang Li Mariano Arcuri Agustin Zorzano Departamento de Geología Universidad Nacional del Sur (UNS) GCS Consulting Services.Bahía Blanca Research Institute of Petroleum Exploration&Development-Northwest Consejo Nacional de Investigaciones Científicas y T ecnicas (CONICET) Shandong University of Science and Technology

Sequence stratigraphic concepts and methods provide novel tools for performing stratigraphic analysis, allowing us to improve our understanding of depositional models and basin evolution. Main controls and depositional elements(e.g., surfaces, systems tracts, parasequences, etc.) recognized in conventional sequence stratigraphy are designed for marine-related systems. In contrast, the sequence stratigraphy of lacustrine successions is much more complex and poorly understood, because it is not driven by sea-level changes, but by a complex interaction between tectonics and high-frequency climatic cycles. The comprehensive analysis of the water balance of lacustrine systems allows the recognition of three types of lake conditions: Underfilled, balanced-fill and overfilled lakes. Understanding the lake conditions in ancient successions is fundamental for unraveling lacustrine sequence stratigraphy, since these conditions effectively control water salinity, internal stacking pattern and the characteristics of systems tracts. Underfilled lakes are hydrologically closed lakes, and consequently, the lake-level can highly fluctuate, driven by high-frequency wet-dry climatic cycles. During wet periods, rivers supply water and sediments, resulting in fining-and thinning-upward elementary depositional sequences(EDS's) accumulated during the transgressive systems tract(TST). In contrast, dry periods are characterized by a relative lake-level fall with the subaerial exposure of lake margin areas during the regressive systems tract(RST). Lake water salinity can fluctuate from brackish to hypersaline. Balanced-fill lakes are partially closed lakes, and consequently, they have characteristics of both underfilled and overfilled lakes. During the TST, the lake is in underfilled condition, and consequently, the introduction of water and sediment will accumulate a fining-upward interval until reaching the spill point during the maximum flooding. The RST is accumulated under an overfille

关键词： Lacustrine sequence stratigraphy Underfilled lakes Balanced-fill lakes Overfilled lakes Forced transgression Forced regression

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Effects of connected automated vehicle on stability and energy consumption of heterogeneous traffic flow system

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Chinese Physics B 2024年第3期33卷 291-301页

作者：申瑾赵建东刘华清姜锐余智鑫 School of Systems Science Beijing Jiaotong UniversityBeijing 100044China Key Laboratory of Transport Industry of Big Data Application Technologies for Comprehensive Transport Beijing Jiaotong UniversityBeijing 100044China School of Maritime and Transportation Ningbo UniversityNingbo 315000China

With the development of intelligent and interconnected traffic system,a convergence of traffic stream is anticipated in the foreseeable future,where both connected automated vehicle(CAV)and human driven vehicle(HDV)will *** order to examine the effect of CAV on the overall stability and energy consumption of such a heterogeneous traffic system,we first take into account the interrelated perception of distance and speed by CAV to establish a macroscopic dynamic model through utilizing the full velocity difference(FVD)***,adopting the linear stability theory,we propose the linear stability condition for the model through using the small perturbation method,and the validity of the heterogeneous model is verified by comparing with the FVD *** nonlinear theoretical analysis,we further derive the KdV-Burgers equation,which captures the propagation characteristics of traffic density ***,by numerical simulation experiments through utilizing a macroscopic model of heterogeneous traffic flow,the effect of CAV permeability on the stability of density wave in heterogeneous traffic flow and the energy consumption of the traffic system is *** analysis reveals emergent traffic *** experimental findings demonstrate that as CAV permeability increases,the ability to dampen the propagation of fluctuations in heterogeneous traffic flow gradually intensifies when giving system perturbation,leading to enhanced stability of the traffic ***,higher initial traffic density renders the traffic system more susceptible to congestion,resulting in local clustering effect and stop-and-go traffic ***,the total energy consumption of the heterogeneous traffic system exhibits a gradual decline with CAV permeability *** evidence has demonstrated the positive influence of CAV on heterogeneous traffic *** research contributes to providing theoretical guidance for future CAV applic

关键词： heterogeneous traffic flow CAV linear stability nonlinear stability energy consumption

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Microstructure and ablation behavior of Zr-based ultra-high-temperature gradient composites

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Transactions of Nonferrous Metals Society of China 2024年第9期34卷 2889-2899页

作者： qing-hua liu Tian TIAN Wei SUN Hong-bo ZHANG Xiang XIONG State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China National Key Laboratory of Science and Technology on High-strength Structural Materials Central South UniversityChangsha 410083China

To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt *** effects of different infiltrant laying methods on the microstructure and ablative properties of Zr-based ultrahigh-temperature gradient composites were *** results showed that the gradient structure of the Zr-based ultrahigh-temperature gradient composites differed when the composition ratio of the infiltrant was *** the thicknesses of the Zr/Mo/Si layers were 6/4/12 mm and 8/2/12 mm,the SiMoZrC solid solution content in the samples increased and decreased along the infiltration direction,*** gradient samples were ablated in an oxyacetylene flame at 3000°C for 40 *** ablation resistance of the sample was the highest when the infiltrant was a powder and the thickness of the Zr/Mo/Si layer was 6/4/12 mm.

关键词： reactive melt infiltration ceramic-matrix composites gradient material microstructure ablation property

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Clastic compaction unit classification based on clay content and integrated compaction recovery using well and seismic data

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Petroleum Science 2016年第4期13卷 685-697页

作者： Zhong Hong Ming-Jun Su hua-qing liu Gai Gao Petro China Research Institute of Petroleum Exploration and Development(RIPED)-Northwest Lanzhou 730020GansuChina Research Institute of Exploration and Development Petro China Changqing Oilfield CompanyXi'an 710018ShaanxiChina

Compaction correction is a key part of paleogeomorphic recovery methods. Yet, the influence of lithology on the porosity evolution is not usually taken into account. Present methods merely classify the lithologies as sandstone and mudstone to undertake separate porositydepth compaction modeling. However, using just two lithologies is an oversimplification that cannot represent the compaction history. In such schemes, the precision of the compaction recovery is inadequate. To improve the precision of compaction recovery, a depth compaction model has been proposed that involves both porosity and clay content. A clastic lithological compaction unit classification method, based on clay content, has been designed to identify lithological boundaries and establish sets of compaction units. Also, on the basis of the clastic compaction unit classification, two methods of compaction recovery that integrate well and seismic data are employed to extrapolate well-based compaction information outward along seismic lines and recover the paleo-topography of the clastic strata in the region. The examples presented here show that a better understanding of paleo-geomorphology can be gained by applying the proposed compaction recovery technology.

关键词： Compaction recovery Porosity-clay contentdepth compaction model Classification of lithological compaction unit Well and seismic data integrated compaction recovery technology

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Synthesis of Novel Bisoxazoline Ligands for the Enantioselective Diels-Alder Reaction

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Chinese Chemical Letters 2006年第8期17卷 1033-1036页

作者： qing hua BIAN Jun liu Ming Ming YIN Min WANG College of Science China Agricultural University Beijing 100094

Four novel bisoxazoline ligands 8a-d were synthesized from （S）-amino alcohols and could be formed effective catalysts （up to 77% ee for endo isomer） with Cu（OTf）2 for enantioselective Diels-Alder addition. The f... 详细信息

关键词： Asymmetry catalytic bisoxazoline Diels-Alder reaction ligand.

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Axial laminar velocity field calculation and optimization for power-law fluid in eccentric annulus with cutting bed

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Journal of Hydrodynamics 2018年第5期30卷 943-949页

作者： Yong-hai Gao Ye Chen De-jun Cai hua-qing liu Cheng-gui liu qing-yong Li School of Petroleum Engineering China University of Petroleum (East China) Qingdao 266580 China National Engineering Laboratory for Testing and Detection Technology of Subsea Equipments Qingdao 266101 China Drilling Department CNPC Offshore Engineering Company Limited Tianjin 300280 China

The formation of a cutting bed in an annulus involves safety problems in drilling especially in the horizontal well and the directional well. In this work, three axial laminar velocity field calculation models for the power-law fluid in an annulus are modified by considering the effect of the cutting bed. The proposed models are employed to numerically simulate the annulus flow with the cutting bed. Verified by the experimental data in literature, all of them can be applied to the situation of the annulus flow with the cutting bed. The modified concentric annulus model enjoys the best performance, while the flat channel flow model has the worst performance.

关键词： Eccentric annulus power-law fluid axial laminar velocity field cutting bed

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Microscopic characterization and formation mechanisms of deep-water sandy-debris-flow and turbidity-current sandstones in a lacustrine basin： a case study in the Yanchang Formation of the Ordos Basin, China

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Petroleum Science 2018年第1期15卷 28-40页

作者： Jian-Bo Liao Ai-hua Xi Zhi-Yong Li hua-qing liu Xiang-Bo Li Rong Wanyan School of Geoscience and Technology Southwest Petroleum University Chengdu 610500 Sichuan China Petro China Research Institute of Petroleum Exploration &Development-Northwest Lanzhou 730020 Gansu China Key Laboratory of Reservoir Description CNPCLanzhou 730020 Gansu China

Deep-water deposition is a current issue in sedimentological research. Sandy-debris-flow sandstones and turbidity-current sandstones are the main types of sandstone that are the focus of considerable disputes in this research. Previous studies mainly focused on description of the macroscopic sedimentary structure and theoretical derivation of the formation mechanisms. The microscopic petrological characteristics, reservoir properties, and formation mechanisms of deep-water sandy-debris-flow and turbidity-current sandstones have been studied in the Yanchang Formation of the Ordos Basin,China, by means of field outcrop surveys, thin-section identification, geochemical element analysis, and porosity and permeability measurements under overburden pressure. The content of detrital grains in the sandy-debris-flow sandstones is high, whereas the contents of mica sheets and matrix are low. The fine-grained matrix is distributed unevenly within the pores. A considerable number of residual intergranular pores are preserved in the middle of single sand bodies, resulting in relatively better reservoir properties. The total number of detrital grains in the turbidite sandstone is low, while it contains abundant mica sheets and matrix. The mica sheets and fine-grained matrix are distributed evenly within the pores, resulting in serious damage to pores and poor reservoir properties. The sandy-debris-flow sandstones in the center of the lake basin form a high-quality reservoir; thus, this area is suitable for oil and gas exploration.

关键词： Sandy debris flow Turbidite Ordos Basin Petrology Reservoir properties

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Effect of nitrogen on microstructure and secondary hardening of H21 die steel

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Journal of Iron and Steel Research International 2019年第5期26卷 483-489页

作者： Jin-bo Gu hua-qing liu Jing-yuan Li Yan-bin Jiang Rui-jin Chang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology Beijing Beijing 100083 China

The effect of nitrogen on the microstructure and secondary hardening of H21 die steel was studied by using scanning electron microscope, X-ray diffraction, transmission electron microscope and dilatometer. The results demonstrate that nitrogen can enhance the secondary hardening behavior of H21 hot-working die steel without toughness lose. Nitrogen addition increases the austenitic phase zone, decreasing austenite transformation temperature and martensite transformation temperature, thereby increasing the retained austenite stability. Retained austenite in quenched steel can dissolve a large quantity of alloy, thereby decreasing the coarsening rate of the precipitates. Trace nitrogen could intensify the refinement of pearlite by decreasing the diffusion rate of alloying element into carbides. Nitrogen increases the amounts and precipitation temperature of the undissolved V(C, N) and suppresses the growth of prior austenite before quenching. During tempering process, parts of nitrogen in V(C, N) dissolved back into the matrix, resulting in the distorting lattice of ferrite, thereby reinforcing the matrix. Meanwhile, the solid-dissolved nitrogen inhibits the growth of carbides by decreasing the diffusion rate of alloying elements.

关键词： Nitrogen Secondary hardening H21 die steel Precipitate

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Chemical Constituents of the Roots of Vernonia cumingiana Benth.

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Journal of Integrative Plant Biology 2005年第8期47卷 1016-1020页

作者： qing-hua liu Jing-Quan YUAN Mao-Rong SUO Jun-Shan YANG Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100094 China Guangxi Botanical Garden of Medicinal Plants Nanning 530023 China

To search for new and bioactive constituents from traditional Chinese medicines, a new steroidal saponin, named vernonioside G （1）, was isolated from the roots of Vernonia cumingiana Benth. （Compositae）. The structure of vernonioside G was elucidated using spectral methods, particularly two-dimensional nuclear magnetic resonance analysis. Together with the new compound, eight known compounds were also isolated and identified from the roots of V. cumingiana, among which, VE-1 （2） and 24-methylenelanost-9（11）- en-3β-ol acetate （3） were assigned NMR data for the first time and compound 3 was obtained as a natural product from a plant for the first time.

关键词： Compositae steroidal saponin Vernonia cumingiana vernonioside G.

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2D NMR-based MatchNat Dereplication Strategy Enables Explosive Discovery of Novel Diterpenoid Alkaloids

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Chinese Journal of Chemistry 2022年第18期40卷 2169-2178页

作者： Tian-Peng Yin Yi Yu qing-hua liu Ming-Yue Zhou Guo-Yuan Zhu Li-Ping Bai Wei Zhang Zhi-Hong Jiang State Key Laboratory of Quality Research in Chinese Medicines Macao Institute for Applied Research in Medicine and HealthGuangdong-Hong Kong-Macao Joint Laboratory of Respiratory Infectious DiseaseMacao University of Science and TechnologyTaipaMacaoChina Faculty of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhaiGuangdong519041 China

The tribe Delphineae,comprising two genera,Aconitum *** Delphinium L.,is the richest source of bioactive diterpenoid alkaloids(DAs),while their highly similar chemical structures create a major challenge for dereplication from complex *** solve the inefficient discovery process of natural DAs,a novel dereplication strategy based on pattern recognition of specific heteronuclear multiple bond correlation(HMBC)signals has been established in this *** strategy utilized the diagnostic signals in the HMBC spectra of C_(19)-DAs,which could indicate the structural *** newly designed software MatchNat allowed in silico recognition of C_(19)-DA *** developed dereplication system was demonstrated to be a practical strategy to dereplicate a variety of natural products from two Delphineae plants,including Aconitum vilmorinianum *** Delphinium pachycentrum *** compounds could be rapidly recognized from the mixture,and novel DAs were found with the aid of ***,targeted isolation led to the explosive discovery of a series of novel *** dereplication system has the potential to be adopted for dereplication of any other class of natural products and has shown promising application as a complementary tool in the nuclear magnetic resonance analysis of traditional Chinese medicines.

关键词： NMR spectroscopy Natural products Alkaloids Dereplication Aconitum

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