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Sediment supply mechanism and its influence on hydrocarbon accumulation in the Paleogene of the northern Huanghekou Sag,Bohai Bay Basin,China

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Journal of Palaeogeography 2023年第2期12卷 229-245页

作者： hai-feng yang Geng Qian Meng Zhao Yan-Fei Gao Wen Su Yao-Hui Xu China National Offshore Oil Corporation Tianjin Branch Tianjin300450China

Tectonic activity and sediment supply have significantly affected the rifted basin fillings and hydrocarbon *** Huanghekou Sag in the southeastern Bohai Bay Basin is a hydrocarbon rich sag and was bounded by the Bonan Uplift to the north in the Paleogene,which strongly affected sediment disribution and hydrocarbon accumulation in this *** sediment supply mechanism of the Paleogene parent rocks in this area has not been revealed ***,the Huanghekou Sag is a natural laboratory to reveal the relationship between the tectonic activties and hydrcoarbon accumulations in a rifted *** this study,the tectonic evolution characteristics of the Bonan Uplift in different geological periods are revealed during the main fault depression ***,the direction of the provenance and distribution of the depositional system of the Bonan Uplift are analyzed based on the sedimentary system and mineralogy ***,the sediment supply in the Bonan Uplift in different geological periods has been systematically *** results indicated that sediment supply is the dominant factor of hydrocarbon accumulation in the Paleogene in the Huanghekou *** the Paleocene-Middle Eocene,extensive denudation occurred in the Bonan Uplift,sediments were mainly sourced from the Bonan Uplift in the northern margin of the Huanghekou *** the Late Eocene to Early Oligocene,the Bonan Uplift had a large angle rotation and subsidence due to the strong rifting of the Bozhong Sag in the north,and the sand supply capacity was seriously *** to the different sediment supply in different geological periods,high quality reservoir and cap conditions were formed in the Paleogene in the central and northern parts of the Huanghekou Sag,which is conducive to the accumulation and preservation of oil and gas.

关键词： Huanghekou Sag Tectonic evolution Fault depression period Recovery of parent rock area Reservoir-cap combination

Mesh‑free semi‑quantitative variance underestimation elimination method in Monte Caro algorithm

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Nuclear Science and Techniques 2023年第1期34卷 157-171页

作者： Peng‑Fei Shen Xiao‑Dong Huo Ze‑Guang Li Zeng Shao hai‑feng yang Peng Zhang Kan Wang Department of Engineering Physics Tsinghua UniversityBeijing 100084China China Nuclear Power Engineering Corporation Beijing 100840China

The inter-cycle correlation of fission source distributions(FSDs)in the Monte Carlo power iteration process results in variance underestimation of tallied physical quantities,especially in large local *** study provides a mesh-free semiquantitative variance underestimation elimination method to obtain a credible confidence interval for the tallied *** method comprises two procedures:Estimation and *** FSD inter-cycle correlation length is estimated in the Estimation procedure using the Sliced Wasserstein distance *** batch method was then used in the elimination *** FSD inter-cycle correlation length was proved to be the optimum batch length to eliminate the variance underestimation *** exemplified this method using the OECD sphere array model and 3D PWR BEAVRS *** results showed that the average variance underestimation ratios of local tallies declined from 37 to 87%to within±5%in these models.

关键词： Monte Carlo algorithm Power iteration process Inter-cycle correlation Variance underestimation Sliced Wasserstein distance

Derivation of Expanded Isospectral-Nonisospectral Integrable Hierarchies via the Column-vector Loop Algebra

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 778-800页

作者： hai-feng WANG Yu-feng ZHANG School of Science Jimei UniversityXiamen 361021China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

A scheme for generating nonisospectral integrable hierarchies is *** on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral *** follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger *** using the trace identity,the biHamiltonian structure of these two hierarchies are also ***,some symmetries and conserved quantities of the resulting hierarchy are discussed.

关键词： expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-Hamiltonian structure symmetry

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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao Zhang Yu-hai Zhang Ying Zou Xiu-Xiu yang Gen Zhang feng-Shou Zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

The role of vitamin E in polyunsaturated fatty acid synthesis and alleviating endoplasmic reticulum stress in sub-adult grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2024年第1期16卷 275-287页

作者： Ke Yao Lin feng Wei-Dan Jiang yang Liu Lu Zhang hai-feng Mi Xiao-Qiu Zhou Pei Wu Animal Nutrition Institute Sichuan Agricultural University Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural University Key Laboratory of Animal Disease-Resistance Nutrition Ministry of Education Ministry of Agriculture and Rural Affairs Key Laboratory of Sichuan Province Tongwei Co. Ltd. Healthy Aquaculture Key Laboratory of Sichuan Province

Vitamin E(VE) is an essential lipid-soluble vitamin that improves the fish flesh quality. However, the underlying molecular mechanisms remain unclear. This study aimed to investigate the effects of VE on growth performance and flesh quality in sub-adult grass carp(Ctenopharyngodon idella). A total of 450fish(713.53 ± 1.50 g) were randomly divided into six treatment groups(three replicates per treatment)and fed for nine weeks with different experimental diets(dietary lipid 47.8 g/kg) that contained different levels of VE(5.44, 52.07, 96.85, 141.71, 185.66, and 230.12 mg/kg diet, supplemented as dl-a-tocopherol acetate). Notably, the treatment groups that were fed with dietary VE ranging from 52.07 to230.12 mg/kg diet showed improvement in the percent weight gain, special growth rate, and feed efficiency of grass carp. Moreover, the treatment groups supplemented with dietary VE level of 141.71,185.66, and 230.12 mg/kg diet showed enhancement in crude protein, lipid, and a-tocopherol contents in the muscle, and the dietary levels of VE ranging from 52.07 to 141.71 mg/kg diet improved muscle pH24h and shear force but reduced muscle cooking loss in grass carp. Furthermore, appropriate levels of VE(52.07 to 96.85 mg/kg diet) increased the muscle polyunsaturated fatty acid content in grass carp. Dietary VE also increased the mRNA levels of fatty acid synthesis-related genes, including fas, scd-1, fad,elovl, srebp1, pparγ, and lxra, and up-regulated the expression of SREBP-1 protein. However, dietary VE decreased the expression of fatty acid decomposition-related genes, including hsl, cpt1, acox1, and ppara,and endoplasmic reticulum stress-related genes, including perk, ire1, atf6, eif2a, atf4, xbp1, chop, and grp78, and down-regulated the expression of p-PERK, p-IRE1, ATF6, and GRP78 proteins. In conclusion,dietary VE increased muscle fatty acid synthesis, which may be partly associated with the alleviation of endoplasmic reticulum stress, and ultimately improves fish fles

关键词： Vitamin E Flesh quality Muscle polyunsaturated fatty acid level Endoplasmic reticulum stress Growth performance Grass carp

Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng ZHU hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

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Journal of Traditional Chinese Medicine 2024年第2期44卷 303-314页

作者： REN Li hai yang yang Xue LUO Xianqin Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases College of Traditional Chinese MedicineChongqing Medical UniversityChongqing 400016China College of Basic Medicine Chongqing Medical UniversityChongqing 400016China

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in ***:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry ***,HEL was found to suppress LPS-induced ALI in ***-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)*** model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI *** counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and ***,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal ***:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora *** study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung *** addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturban

关键词： Yemazhui(Herba Eupatorii Lindleyani) acute lung injury anti-inflammation toll-like receptor 4 nuclear factor kappa-B nod-like receptor family pyrin domain-containing 3 protein signal transduction gastrointestinal microbiome

Strong Limit Theorems for Weighted Sums under the Sub-linear Expectations

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 862-874页

作者： feng-xiang feng Ding-cheng WANG Qun-ying WU hai-wu HUANG School of Mathematics and Statistics Guilin University of TechnologyGuilin 541004China School of Mathematical Science University of Electronic Science and Technology of ChinaChengdu 611731China School of Science Guilin University of Aerospace TechnologyGuilin 541004China

In this article,we study strong limit theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** establish general strong law and complete convergence theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** results of strong limit theorems are more general than some related results previously obtained by Thrum(1987),Li et al.(1995)and Wu(2010)in classical probability space.

关键词： sub-linear expectation complete convergence complete moment convergence the maximal weighted sums

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques

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Research in Astronomy and Astrophysics 2024年第1期24卷 245-264页

作者： Shi-hai yang Bo Xu Xin Li School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is ***, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

关键词： minor planets asteroids:general celestial mechanics Planetary Systems