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Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing fang Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

Pulmonary embolism secondary to acute anterior ST-elevation myocardial infarction:a case report

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World Journal of Emergency Medicine 2024年第2期15卷 139-141页

作者： Lin Yuan Hong Li Yuhong mi Ying liang Emergency Critical Center Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Thrombophilia denotes a condition,whether acquired or hereditary,characterized by increased susceptibility to hypercoagulation.[1]This condition was first described in 1965,coinciding with the discovery of an inherited predisposition to venous thromboembolism(VTE)in patients deficient in antithrombin III.[2]While arterial and venous thromboses are common in hospitalized patients,acute myocardial infarction(Ami)and pulmonary embolism(PE)stand out as ***,theoccurrenceof Ami complicated by PE is exceedingly rare,especially when considering cases where paradoxical embolism originating from a patent foramen ovale is *** report presents a case of Ami complicated with PE.A comprehensive understanding of the pathophysiology of this rare yet critical condition is important for ensuring prompt diagnosis and treatment.

关键词： embolism infarction acute

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI ming liang fang Xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new *** is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of *** method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding *** makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the ***,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

Effect of catalyst diesel particulate filter aging and catalyst loadings on particulate emission characteristics from a diesel vehicle

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Journal of Environmental Sciences 2024年第2期136卷 35-44页

作者： Yunhua Zhang Diming Lou Piqiang Tan Zhiyuan Hu liang fang School of Automotive Studies Tongji UniversityShanghai 201804China

In this study,the effect of new and used catalyzed diesel particulate filter(CDPF)with different catalyst loadings on the particulate emissions including the particle mass(PM),particle number(PN),particle size distribution(PSD)and geometric mean diameter(GMD)from a diesel vehicle were investigated based on a heavy chassis *** showed that more than 97.9%of the PN and 95.4%of the PM were reduced by the CDPF,and the reduction efficiency was enhanced by the catalyst *** using the CDPF,the PSD transformed from bimodal to trimodal with the peak shifting towards smaller particle size,more nucleation mode particles were reduced compared with accumulation mode ones,but the reduction effect on the accumulation mode particles was more significantly influenced by the catalyst ***,the CDPF increased the accumulation mode particles proportion,producing a larger *** the used CDPF,its reduction effect on the particulate emissions enhanced,especially for the PM in accumulation *** PSD returned to bimodal,but the peak at accumulation mode began to be higher than that at nucleation mode,illustrating that more nucleation mode particles was *** aging of the CDPF resulted in greater effect on the PN-based PSD than that of PM-based PSD,but the effect of catalyst loading on the PN and PM emission factors was *** used CDPF further increased the GMD,and the effect of catalyst loading on the GMD was strengthened,a higher catalyst loading led to a reduction in the GMD.

关键词： Catalyzed diesel particulate filter (CDPF) Catalyst loading Aging Particle Particle size distribution Geometric mean diameter

Spatiotemporal Characteristics of Typical Ecosystem Services and Their Spatial Responses to Driving Factors in Ecologically Fragile Areas in Upper Yellow River,China

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Chinese Geographical Science 2024年第4期34卷 674-688页

作者： liang Gui fang Fengman LIN Yuesheng ZHANG Zhiming School of Geography and Tourism Anhui Normal UniversityWuhu 241003China Key Laboratory of Earth Surface Processes and Regional Response in the Yangtze Huaihe River Basin Anhui Normal UniversityWuhu 241003China

The identification of dominant driving factors for different ecosystem services(ESs)is crucial for ecological conservation and sustainable ***,the spatial heterogeneity of the dominant driving factors affecting various ESs has not been adequately elucidated,particularly in ecologically fragile *** study employed the integrated valuation of ESs and trade-offs(InVEST)model to evaluate four ESs,namely,water yield(WY),soil conservation(SC),habitat quality(HQ),and carbon storage(CS),and then to identify the dominant driving factors of spatiotemporal differentiation of ES and further to characterize the spatial heterogeneity characteristics of the dominant driving factors in the eco-fragile areas of the upper Yellow River,China from 2000 to *** results demonstrated that WY exhibited northeast-high and northwest-low patterns in the upper Yellow River region,while high values of SC and CS were distributed in central forested areas and a high value of HQ was distributed in vast grassland *** CS,WY,and SC exhibited decreasing trends over *** most critical factors affecting WY,SC,HQ,and CS were the actual evapotranspiration,precipitation,slope,and normalized difference vegetation index,*** addition,the effects of different factors on various ESs exhibited spatial *** results could provide spatial decision support for eco-protection and rehabilitation in ecologically fragile areas.

关键词： integrated valuation of ecosystem services and trade-offs(InVEST)model geographically weighted regression(GWR) natural factor spatial heterogeneity Lanxi urban agglomeration upper Yellow River China

Assessment and Enhancement of FRC of Power Systems Considering Thermal Power Dynamic Conditions

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1371-1383页

作者： Feng Hong Yalei Pang Weiming Ji Lu liang fang fang Junhong Hao Jizhen Liu State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources and School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Alternate Electric Power System with Renewable Energy Sources School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China

Frequency stability and security have been a vital challenge as large-scale renewable energy is integrated into power *** contrast,the proportion of traditional thermal power units decreases during the decarbonization transformation process,resulting in poor frequency *** paper aims to explore the potential of frequency regulation support,dynamic assessment,and capacity promotion of thermal power plants in the transition *** the dynamic characteristics of the main steam working fluid under different working conditions,a nonlinear observer is constructed by extracting the main steam pressure and valve opening degree *** real-time frequency modulation capacity of thermal power units can provide a dynamic state for the power grid.A dynamic adaptive modification for primary frequency control(PFC)of power systems,including wind power and thermal power,is proposed and *** power dynamic allocation factor is adaptively optimized by predicting the speed droop ratio,and the frequency modulation capability of the system is improved by more than 11%under extreme ***,through the Monte Carlo simulation of unit states of the system under various working conditions,the promotion of the frequency regulation capacity with high wind power penetration(WPP)is verified.

关键词： Dynamic evaluation frequency regulation power system predictive modeling wind penetration

What can we learn from recent 2νββexperiments?

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Chinese Physics C 2024年第3期48卷 93-103页

作者：房栋梁 Institute of Modern Physics Chinese Academy of sciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Recent measurements of the two neutrino double beta decay high precision electron spectra,combined with charge exchange orβ-decay experimental data,have revealed severe constraints across current nuclear many body *** calculations show that the quasi-particle random phase approximation(QRPA)approach can adequately reproduce the measured spectra for the two open shell nuclei,^(82)Se and ^(100)*** the closed shell nucleus ^(136)Xe,QRPA can also reproduce the spectra with proper *** the high-lying state reduction,we also find that the nuclear shell model can also adequately reproduce the spectra and Gamow-Teller transition strength under a unique quenched axial-vector coupling constant *** ^(136)Xe,we find that flipping the sign for the decay strength causes the spectra to go beyond the so-called high-lying state dominance *** results call for future high precision measurements of charge-exchange reactions.

关键词： nuclear stucture double beta decay electron spectra

Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2479-2505页

作者： mingzhe Huang mi Xiao liang Gao mian Zhou Wei Sha Jinhao Zhang State Key Lab of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight *** this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is *** method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell *** geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational *** topological configurations of thin-shell structures are described by constructing the effective density field on the *** volume constraints are imposed in the proximity of each control point to obtain bone-like cellular *** facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global *** numerical examples are provided to demonstrate the effectiveness of the proposed *** simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness.

关键词： Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells

Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： Chao liang Shichao JI Yingchang CAO Keyu LIU Jing WU fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their *** on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this *** the microscopic scale,each type of pyrite is associated with a different formation *** are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous *** pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal *** morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron *** addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen ***,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element