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Terrestrial records of the early Albian Ocean Anoxic Event:Evidence from the Fuxin lacustrine basin,NE China

Geoscience Frontiers 2022年第1期13卷 138-157页

作者： Xiao-Tao Xu Long-Yi Shao Kenneth A.Eriksson Bo Pang Shuai Wang Cheng-Xue Yang hai-hai hou College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Shandong Key Laboratory of Depositional Mineralization&Sedimentary Mineral Shandong University of Science and TechnologyQingdao 266590China Department of Geosciences Virginia TechBlacksburgVA 24061USA Liaoning Province Geology and Minerals Group Energy Geology Co. Ltd.Shenyang 110000China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China College of Mining Liaoning Technical UniversityFuxin 123000China

The early Albian Oceanic Anoxic Event 1 b(OAE 1 b) is well documented in the Tethys, Pacific and North Atlantic, but few studies have evaluated whether or not terrestrial records of OAE 1 b exist. In order to identify terrestrial records of the early Albian OAE 1 b and to infer possible driving mechanisms, an integrated multi-proxy study from the late Aptian to Albian in the Fuxin lacustrine basin was conducted,including thick, organic-rich black mudstones, total organic carbon(TOC), organic carbon isotopes(d13 Corg), mercury concentration(Hg) and results from pyrolysis analyses(S2, Tmaxand HI). Results show three distinct short-term negative d13 Corgexcursions corresponding with relatively high TOC values,which could be counterparts of the Kilian, Paquier and Leenhardt sub-events of the early Albian OAE1 b. Atmospheric CO2 concentration(p CO2) recovered from C3 plant d13 Corgcompositions indicates an increasing trend in Unit C during the early Albian, and there are three short-term increases of p CO2 corresponding to the three sub-events of OAE 1 b at this time interval. We infer that a trend of increasing p CO2 during the Kilian sub-event in the study area is closely related to volcanism. Continental weathering calculated using chemical weathering indices(CIA, WIP and MIA(O)) show an increasing trend during the OAE 1 b interval, likely resulting from warmer and more humid conditions. Mixed sources of terrestrial plants and lacustrine plankton demonstrated by pyrolysis analyses(HI vs. Tmaxand S2 vs. TOC), indicate a terrestrial contribution to the organic-rich sediments of the Kilian, Paquier and Leenhardt sub-events of OAE 1 b. We suggest that a CO2-forced greenhouse effect during the early Albian might have triggered the relatively warm and humid palaeoclimatic conditions, and intensified chemical weathering that combined to create high nutrient and organic matter levels that were flushed into lakes contributing to eutrophication and anoxia in lacustrine and in c

关键词： Fuxin Basin Early Albian Organic carbon isotopes Ocean Anoxic Event 1b Terrestrial records

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Continental chemical weathering during the Early Cretaceous Oceanic Anoxic Event(OAE1b): a case study from the Fuxin fluvio-lacustrine basin, Liaoning Province,NE China

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Journal of Palaeogeography 2020年第2期9卷 246-266页

作者： Xiao-Tao Xu Long-Yi Shao Bo Lan Shuai Wang Jason Hilton Jian-Yi Qin hai-hai hou Jie Zhao College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Shandong Key Laboratory of Depositional Mineralization&Sedimentary Mineral Shandong University of Science and TechnologyQingdao 266590China Northeast China Coalfield Geology Bureau 107 Exploration Team Fuxin 123000China School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK College of Mining Liaoning Technical UniversityFuxin 123000China.

This study focuses on Early Cretaceous mudstones from the Shahai and Fuxin formations in the Fuxin continental basin. We analyse chemical weathering, land surface temperatures and palaeoclimates based on chemical weathering indices, and emphasize the implications of continental chemical weathering on nutrient fluxes into lakes and *** to Cr and Ni abundance, Al2O3-TiO2, La/Sc-Th/Co and V-Ni-Th×10 plots, as well as rare earth element(REE)analysis, mudstone samples from the Shahai and Fuxin formations were derived from the same type of provenance comprising mainly felsic igneous rocks. Chemical weathering trends reflected by the Chemical Index of Alteration(CIA),Weathering Index of Parker(WIP) and the Mafic Index of Alteration for Oxidative weathering environments(MIA(O)) are consistent with each other and allow the geological succession to be divided into four stages. Land surface temperatures of the Shahai and Fuxin formations are estimated based on the linear relationship of CIA to temperature,and also can be divided into four stages consistent with those determined from chemical weathering trends. During Stage A(early part of the late Aptian) chemical weathering and land surface temperatures were relatively low and showed characteristic high fluctuations, while Stage B(latest Aptian) represented a transitional period where weathering rates and temperatures increased, and high amplitude fluctuations continued. Conditions changed markedly in Stage C(early Albian) with very high and stable weathering, and warm, humid climates, while in Stage D(middle and late Albian) conditions returned to low chemical weathering and land surface temperatures. These stages of chemical weathering and land surface temperature fluctuations represent responses to global climate fluctuations during the Early Cretaceous, with the early Albian high weathering intensities and warm, humid climates combining to create high nutrient levels that would have flushed through rivers int

关键词： Chemical weathering indices Land surface temperature Mudstone Greenhouse conditions Ocean Anoxic Event 1 b Black shales

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四波混频Autler-Townes分裂中的探测光影响

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原子与分子物理学报 2025年第3期42卷 110-115页

作者：裴丽娅侯海龙北京化工大学数理学院北京100029

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的A... 详细信息

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的AT分裂双峰却会逐渐趋于对称分布.详细讨论了探测光场对原子的缀饰影响,提出通过探测光强度可以调控原子两基态之间的有效Raman相干,从而影响AT分裂双峰的特征.

关键词：四波混频原子相干 Autler-Townes分裂缀饰态横向弛豫率

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Dual-threshold symbol selective relaying in cooperative networks

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1057-1063页

作者： Peiyao Yang hai Li Shujuan hou School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

In order to efficiently mitigate error propagation and reduce computational complexity, this paper proposes a scheme for traditional cooperative networks, named as dual-threshold symbol selective demodulate-and-forward. In the scheme, two log likelihood ratio(LLR)-based thresholds are devised to measure the reliability of received signals for the relay and the destination, respectively. One of the threshold guarantees that the relay only forwards reliable symbols, thus less error will be propagated to the destination. The other threshold is used at the destination for determining the reliability of symbols received from the *** destination will directly demodulate reliable symbols received from the source. Otherwise, when the symbols received from the source are not reliable, the maximum ratio combiner(MRC) is used to combine symbols received from the source and the ***-form expression of the bit error probability(BEP) of the proposed scheme is derived and analyzed under binary phase shift keying(BPSK) modulation. Then, the relationship and closed-form solutions of two LLR-based thresholds are derived. Simulation results prove that the theoretical BEP of the proposed scheme closely matches the simulated ones. The proposed scheme can achieve high performance with low computational complexity compared to existing schemes.

关键词： demodulate-and-forward relaying strategies error propagation cooperative networks

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Electrochem ically Enabled Intram olecular Am inooxygenation of Alkynes v ia Am idyl Radical Cyclization

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Chinese Journal of Chemistry 2020年第4期38卷 394-398页

作者： Zhong-Wei hou hai-Chao Xu State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMKey Laboratory of Chemical Biology of Fujian Provinceand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005Chino

Summary of main observation and conclusion An electrochemical synthesis of oxazol-2-ones and imidazol-2-ones has been developed via 5-exo-dig cyclization of propargylic carbamates-and ureas-derived amidyl *** electrosynthesis relies on the dual function of 2,2,66-tetramethylpiperidin-1-y oxyl(TEMPO)as a redox mediator for amidyl radical formation and an oxygen atom *** reactions are conducted under mild conditions using a simple setup and provide convenient access to functionalized oxazol-2-ones and imidazol-2-ones from readily available materials.

关键词： materials. donor readily

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Perturbation of Spectra for a Class of 2×2 Operator Matrices

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 711-720页

作者： ALATANCANG Guo-lin hou Guo-jun hai School of Mathematical Sciences Inner Mongolia University

In this paper, we study the perturbation of spectra for 2 ×2 operator matrices such as Mx ={A0 XB） AC and Mz = （Az CB） on the Hilbert space H K and the sets……

关键词： operator matrices point spectrum residual spectrum continuous spectrum perturbation ofspectrum

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Effect of Cr Doping on the Surface Characteristics of Ni Metal Studied with First-Principles Calculation

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 461-470页

作者： Xian-Feng Sun hai-Tao Wang En-hou Han CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The influence of Cr doping on the surface characteristics of Ni metal, including the surface energy, work function,adsorption and dissociation, has been investigated by means of first-principles calculation based on density functional theory. The results reveal that with the increase in Cr doping amount, the surface energies for all(111),(110) and(100)surfaces increase, whereas the work functions of(111) and(100) surfaces decrease followed by an increase and that of(110) surface has been decreasing. On the typical Ni(111) and Ni-Cr(111) surfaces, the adsorption energies follow the sequence O > OH > H > H_2O, and the doping of Cr increases the chemical activity of surfaces leading to the improvement of adsorption energies. The H_2O dissociating to OH and H is easier than the subsequent OH dissociating to O and H. The addition of Cr into Ni surface decreases the energy barriers and significantly increases the reaction rate constants.

关键词： Density functional theory Surface characteristics Nickel Cr addition Atomistic simulation

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ABP41 is Involved in the Pollen Tube Development via Fragmenting Actin Filaments

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Molecular Plant 2008年第6期1卷 1048-1055页

作者： Ting Wang Yun Xiang Jian hou hai-Yun Ren Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education Beijing Normal University Beijing 100875 People's Republic of China

ABP41 is identified as a novel member of plant villin/gelsolin/fragmin superfamily proteins from lily pollen, which binds stoichiometrically to actin filaments and severs them in vitro. To further understand its in-vivo function and the potential molecular mechanisms, biochemical analysis, fluorescence microscopic observation and microinjection assays were performed. Different biochemical measurements showed that ABP41 maintained actin filaments in forms of short F-actin in vitro. Microinjection of ABP41 into pollen tubes could fragment the pre-existing actin filaments, inhibit the velocity of cytoplasmic streaming, and shorten the length of the clear zone of pollen tube. In addition, it was found that the endogenous ABP41 expressing level was dynamically corresponding to the short actin filament structure in pollen at different stages of pollen germination. Our results suggest that ABP41 is involved in the regulation of actin dynamics during the pollen germination process via maintenance of short dynamic actin filaments.

关键词： ABP41 actin filament fragmentation pollen germination actin-binding protein.

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Material removal mechanisms and characteristics of potassium dihydrogen phosphate crystals under nanoscratching

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Advances in Manufacturing 2021年第4期9卷 558-567页

作者： Ning hou Yong Zhang Liang-Chi Zhang Ming-hai Wang School of Mechatronics Engineering Shenyang Aerospace UniversityShenyang 110136People’s Republic of China Key Laboratory of Fundamental Science for National Defense of Aeronautical Digital Manufacturing Process Shenyang Aerospace UniversityShenyang 110136People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongPeople’s Republic of China

Potassium dihydrogen phosphate(KDP)crystals are important materials in high-energy laser ***,because these crystals are brittle and soft,machining-induced defects often emerge in KDP *** study aimed to investigate the material removal mechanisms and characteristics of KDP during nanoscratching using Berkovich,spherical,and conical *** found that KDP surface layers could be removed in a ductile mode at the micro/nanoscale and that dislocation motion was one of the main removal *** characteristics are related to the stress fields generated by indenter *** spherical indenter achieved a ductile removal mode more *** lateral force of nanoscratching increased with an increase in the normal *** coefficient of friction(COF)followed the same trend as the lateral force when spherical and conical indenters were ***,the COF was independent of the normal force when using a Berkovich *** found that these COF variations could be accurately described by friction models.

关键词： Potassium dihydrogen phosphate(KDP)crystals Removal mechanism Nanoscratching Indenter geometry

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Power Allocation with Proportional Fairness in Downlink NOMA System

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Journal of Beijing Institute of Technology 2018年第3期27卷 371-378页

作者： Hanyu Zheng hai Li Shujuan hou School of Information and Electronics Beijing Institute of Technology

The non-orthogonal multiple access(NOMA)has been regarded as a candidate radio access technology in the 5 th generation(5 G)mobile *** this paper,the problem of power allocation is considered with proportional fairness for downlink *** objective is to maximize the logarithmic throughput of the system,which achieves a good tradeoff between the system throughput and user *** approximate optimal solution of this proposed method can be found by the means of quasiNewton *** any number of users K,the numerical results verify the accuracy and convergence of our proposed *** to the exhaustive search method,the computational complexity is significantly reduced when the two methods achieve the same ***,we show that as the number of users increases,the number of iterations of our method increases with an approximately linear trend.

关键词： non-orthogonal multiple access(NOMA) power allocation proportional fairness logarithmic throughput

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