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Chinese Journal of Aeronautics 2024年第10期37卷 83-102页

作者： Ruoye xiao dong SUN Jian yu School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Aerodynamics Mianyang 621000China

Shock wave/boundary layer interaction in a 24°turning angle of the compression ramp at Mach number 2.9 controlled by steady microjet is investigated using direct numerical *** different jet spacings which are termed as sparse,moderate and dense are considered,and the induced vortex system and shock structures are compared.A moderate jet spacing configuration is found to generate counter-rotating vortex pairs that transport high-momentum fluid towards the vicinity of wall and strengthen the boundary layer to resist separation,reducing the separation *** dense jet spacing configuration creates a larger momentum deficit region,reducing the friction downstream of the *** of pressure and pressure gradient reveals that dense jet spacing configuration reduces the intensity of separation *** impact of varying jet spacings on the turbulent kinetic energy transport mechanism is also investigated by decomposing the budget terms in the transport ***,the spectral characteristics of the separation region are studied using power spectral density and dynamic mode decomposition methods,revealing that moderate jet spacing configuration suppresses low-frequency fluctuations in the separation region.

关键词： Shock wave/boundary layer interaction Compression ramp Steady microjet Different jet spacings Direct numerical simulation

GPa-level pressure-induced enhanced corrosion resistance in TiZrTaNbSn biomedical high-entropy alloy

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China Foundry 2024年第3期21卷 265-275页

作者： xiao-hong Wang yu-lei Deng Qiao-yu Li Zhi-xin Xu Teng-fei Ma Xing Yang Duo dong dong-dong Zhu xiao-hong Yang Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina School of Materials Science and Engineering Taizhou UniversityTaizhou 318000ZhejiangChina

TiZrTaNb-based high-entropy alloys(HEAs)are research frontier of biomedical materials due to their high hardness,good yield strength,excellent wear resistance and corrosion ***,as an essential trace element in the human body that plays a significant role in physiological *** has stable chemical properties and a low elastic *** this study,a new material,TiZrTaNbSn HEAs,was proposed as a potential biomedical *** Ti_(35)Zr_(25)Ta_(15)Nb_(15)Sn_(10)biomedical high-entropy alloys(BHEAs)were successfully prepared through an arc melting furnace and then remelted using a German high-temperature and high-pressure apparatus under GPa-level(4 GPa and 7 GPa).The precipitation behavior of the needle-like HCP-Zr_(5)Sn_(3)phase that precipitates discontinuously at the grain boundary was successfully *** phase constitution,microstructure,and corrosion resistance of the alloy were *** results show that the needle-like HCP-Zr_(5)Sn_(3)phase is eliminated and the(Zr,Sn)-rich nano-precipitated phase is precipitated in the microstructure under high pressure,which leads to the narrowing of grain boundaries and consequently improves the corrosion resistance of the *** addition,the formation mechanisms of(Zr,Sn)-rich nanoprecipitates in BHEAs were *** Zr and Sn dissolve in the matrix due to the effect of high pressure,during the cooling process,they precipitate to form a(Zr,Sn)-rich nano-precipitated phase.

关键词： biomedical HEAs precipitation grain boundary corrosion resistance TiZrTaNbSn

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi yu yu-ying Li yu-bao xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Field-based evidence for the enrichment of intrinsic antibiotic resistome stimulated by plant-derived fertilizer in agricultural soil

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Journal of Environmental Sciences 2024年第1期135卷 728-740页

作者： Shihai Liu Ziming Han dong Zhu xiao Luan Liujie Deng Liping dong Min Yang yu Zhang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Environmental Protection Engineering Center for Harmless Treatment and Resource Utilization of Antibiotic Residues Khorgos 835007China University of Chinese Academy of Sciences Beijing 100049China

Animal manures have been demonstrated to enhance antibiotic resistance in agricultural ***,little is known about the effects of plant-derived fertilizer on soil antibiotic ***,metagenomic sequencing was used to investigate the effects of a plantderived fertilizer processed from sugarcane and beet on soil antibiotic resistance genes(ARGs)in a soybean field along crop growth *** profiles in the soils amended by plant-derived fertilizer were compared with those in the soils amended by chicken *** abundance and diversity of total ARGs in the soils amended by plant-derived fertilizer were significantly(P<0.05)elevated at the sprout stage,to a level comparable to that in the manured ***,unlike chicken manure mainly introducing manure-borne ARGs to soil,the plant-derived fertilizer was indicated to mainly enrich multidrug resistance genes in soil by nourishing indigenous *** with abundances in amended soils significantly(P<0.05)higher than in unamended soils at the sprout stage of soybean were considered as enriched *** in the abundance of the enriched ARGs was observed in both the amended soils from the sprout to the *** analysis further identified Proteobacteria and Bacteroidetes as the primary bacterial taxa involved in the temporal variation of the enriched ARGs in the soils amended by plant-derived fertilizer,while in manured soils were Firmicutes and *** revealed by multivariate statistical analyses,variation of the enriched ARGs in the soils amended by plant-derived fertilizer was majorly attributed to the response of co-occurred bacteria to depleting nutrients,which was different from the failed establishment of manure-borne bacteria in the manured *** study provided field-based evidence that plant-derived fertilizer stimulated the intrinsic antibiotic resistome,and proposed attention to the un-perceived risk since some clinically relevant ARGs originate and evolve fr

关键词： Organic fertilizer Intrinsic antibiotic resistance Indigenous bacteria Metagenomic sequencing

The impact of female sex hormones on cardiovascular disease:from mechanisms to hormone therapy

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Journal of Geriatric Cardiology 2024年第6期21卷 669-681页

作者： Yi KAN yu-Lu PENG Ze-Hao ZHAO Shu-Tong dong Yin-xiao XU xiao-Teng MA xiao-Li LIU yu-Yang LIU yu-Jie ZHOU Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic DiseaseClinical Center for Coronary Heart DiseaseCapital Medical UniversityBeijingChina

Cardiovascular disease remains the leading cause of mortality in women,yet it has not raised the awareness from the *** pathogenesis of cardiovascular disease differs significantly between females and males concerning the effect of sex *** and progestogen impact cardiovascular system through genomic and non-genomic *** menopause,cardiovascular protective effects of estrogens have been well *** were often used in combination with estrogens in hormone *** in sex hormone levels,particularly estrogen deficiency,were considered the specific risk factor in women’s cardiovascular ***,considerable heterogeneity in the impact of hormone therapy was observed in clinical *** heterogeneity is likely closely associated with factors such as the initial time,administration route,dosage,and formulation of hormone *** review will delve into the pathogenesis and hormone therapy,summarizing the effect of female sex hormones on hypertension,pre-eclampsia,coronary heart disease,heart failure with preserved ejection fraction,and cardiovascular risk factors specific to women.

关键词： impact dosage protective

Evaluating effectiveness and safety of combined percutaneous transhepatic gallbladder drainage and laparoscopic cholecystectomy in acute cholecystitis patients:Meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1407-1419页

作者： yu Li Wei-Ke xiao xiao-Jun Li Hui-yuan dong Department of General Surgery No.942 Hospital of PLAYinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Acute cholecystitis(AC)is a common disease in general *** cholecystectomy(LC)is widely recognized as the"gold standard"surgical procedure for treating *** low-risk patients without complications,LC is the recommended treatment plan,but there is still controversy regarding the treatment strategy for moderate AC patients,which relies more on the surgeon's experience and the medical platform of the visiting *** transhepatic gallbladder puncture drainage(PTGBD)can effectively alleviate gallbladder inflammation,reduce gallbladder wall edema and adhesion around the gallbladder,and create a"time window"for elective *** To compare the clinical efficacy and safety of LC or PTGBD combined with LC for treating AC patients,providing a theoretical basis for choosing reasonable surgical methods for AC *** In this study,we conducted a clinical investigation regarding the combined use of PTGBD tubes for the treatment of gastric cancer patients with *** performed searches in the following databases:PubMed,Web of Science,EMBASE,Cochrane Library,China National Knowledge Infrastructure,and Wanfang *** search encompassed literature published from the inception of these databases to the ***,relevant data were extracted,and a meta-analysis was conducted using RevMan 5.3 *** A comprehensive analysis was conducted,encompassing 24 studies involving a total of 2564 *** patients were categorized into two groups:1371 in the LC group and 1193 in the PTGBD+LC *** outcomes of the meta-analysis revealed noteworthy disparities between the PTGBD+LC group and the LC group in multiple dimensions:(1)Operative time:Mean difference(MD)=17.51,95%CI:9.53-25.49,P<0.01;(2)Conversion to open surgery rate:Odds ratio(OR)=2.95,95%CI:1.90-4.58,P<0.01;(3)Intraoperative bleeding loss:MD=32.27,95%CI:23.03-41.50,P<0.01;(4)Postoperative hospital stay:MD=1.44,95%CI:0.14-2.73,P=0.03;(5)Overall posto

关键词： Acute cholecystitis Laparoscopic cholecystectomy Percutaneous transhepatic gallbladder drainage Metaanalysis Efficacy

On Minor Left Prime Factorization Problem for Multivariate Polynomial Matrices

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Journal of Systems Science & Complexity 2024年第3期37卷 1295-1307页

作者： LU dong WANG Dingkang xiao Fanghui School of Mathematics Southwest Jiaotong UniversityChengdu 610031China KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China

A new necessary and sufficient condition for the existence of minor left prime factorizations of multivariate polynomial matrices without full row rank is *** key idea is to establish a relationship between a matrix and any of its full row rank *** on the new result,the authors propose an algorithm for factorizing matrices and have implemented it on the computer algebra system *** examples are given to illustrate the effectiveness of the algorithm,and experimental data shows that the algorithm is efficient.

关键词： Free modules Grobner bases minor left prime(MLP) multivariate polynomial matrices polynomial matrix factorizations

Quantum state tomography from observable time traces in closed quantum systems

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Control Theory and Technology 2024年第2期22卷 222-234页

作者： Shuixin xiao yuanlong Wang Qi yu Jun Zhang Daoyi dong Ian R.Petersen University of Michigan–Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai200240China School of Engineering The Australian National UniversityCanberraACT2601Australia Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China Centre for Quantum Computation and Communication Technology(Australian Research Council) Centre for Quantum DynamicsGriffith UniversityBrisbaneQLD4111Australia School of Engineering and Technology University of New South WalesCanberraACT2600Australia

The task to estimate all the parameters of an unknown quantum state, also called quantum state tomography, is essential for characterizing and controlling quantum systems. In this paper, we utilize observable time traces to identify the initial quantum state of a closed quantum system, based on the state space approach in the control theory. In the informationally complete scenario, we show that with a linear regression estimation (LRE), the mean squared error (MSE) scales as , where N is the resource number. In the informationally incomplete scenario, we introduce regularization LRE to perform the state tomography task. We employ PBH test to demonstrate that closed quantum systems with only one observable are informationally incomplete and propose using observables, where d is the dimension of the quantum state, for informational completeness. Numerical examples demonstrate the effectiveness of our method.

关键词： Quantum state tomography Time trace Quantum system identification

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-yu Li Li-Le Liu Guo-Xiang dong xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

Revisiting the sodium-ion storage capability of hard carbon in carbonate-based electrolytes via a sodium-metal-free protocol

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Science China Chemistry 2024年第7期67卷 2240-2247页

作者： Gaopan Liu Yanbing Mo Jiawei Chen yu Peng xiao Zhu Fei Wang xiaoli dong Yongyao Xia Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyLaboratory of Advanced MaterialsFudan UniversityShanghai 200438China

Common evaluation methodology of sodium(Na)-containing two-electrode or three-electrode configurations overlooks the interference from highly reactive Na metal,leading to the underestimation or inconsistent performance of low-potential hard carbon(HC)***,the trap of Na metal was systematically investigated with or without applied current,uncovering its inadequacy as the reference or counter electrode in different configurations.A Na-metal-free three-electrode protocol is proposed for evaluating the actual Na^(+)-storage capability of the typical low-potential HC *** avoiding Na crosstalk and precisely controlling the working electrode's potential,the actual electrochemical performance of HC in the carbonate esterbased electrolyte can be recognized with high capacity of 222 mAh g^(-1)at 2 C and 113 mAh g^(-1)at 5 C,correcting the misunderstanding of the inferior performance of HC in coin-type half cells(68%and 50%undervaluation at 2 C and 5 C,respectively).The advanced protocol is expected to reduce misunderstandings or underestimation due to evaluation methods and to guide the development of high-performance battery materials.

关键词： highly reactive sodium potential drift carbonate ester sodium-metal-free protocol sodium storage capability