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Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 11-19页

作者： Ziwei Wang lei lei Hao Jiao Lei Feng Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Physics McGill UniversityMontreal H3A 2T8Canada

Recently,pulsar timing array(PTA)experiments have provided compelling evidence for the existence of the nanohertz stochastic gravitational wave background(SGWB).In this work,we demonstrated that cosmic string loops generated from cosmic global strings offer a viable explanation for the observed nanohertz SGWB data,requiring a cosmic string tension parameter of log(Gμ)~-12 and a loop number density of log N~4.Additionally,we revisited the impact of cosmic string loops on the abundance of massive galaxies at high redshifts.However,our analysis revealed challenges in identifying a consistent parameter space that can concurrently explain both the SGWB data and observations from the James Webb Space Telescope.This indicates the necessity for either extending the existing model employed in this research or acknowledging distinct physical origins for these two phenomena.

关键词： nanohertz stochastic gravitational-wave background cosmic string loop JamesWebb Space Telescope galaxy formation

Engineering yolk-shell CuCo_(2)S_(4)@Cu_(2)O Z-scheme nanoreactors for accelerating generation of value-added chemicals and of degradation multi-organic contaminants

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Journal of Materials Science & Technology 2023年第25期156卷 54-63页

作者： Xue feng lei Zhang College of Chemistry Liaoning University66 Chongshan Middle RoadShenyang 110036China

The synthesis of solar-driven chemical value-added products and the degradation of pollutants is a promising approach for sustainable development. However, achieving these works via photocatalysts with efficient charge-separation, photo-absorption is challenging. A yolk-shell CuCo_(2)S_(4)@Cu_(2)O Z-scheme nanoreactor (YS-CuCo_(2)S_(4)@Cu_(2) O-NR) with octahedron Cu_(2)O as the core and tubular CuCo2 S4 as the shell, has been synthesized by regulating composition and morphology. YS-CuCo_(2)S_(4)@Cu_(2)O-NR shows superior photocatalytic activities for producing H_(2) O_(2) collaborates by selective oxidation of benzyl alcohol (BA) to high value-added benzaldehyde (BAD)/utilized Fenton-like reaction to degrade multi-pollutants through space-confinement effect, reaching 80% conversion and 99% selectivity of BA, a yield of 12 mM g^(−1) for H_(2)O_(2) and above 90% degradation efficiency for multi-pollutants. A photocatalysis nanoconfinement reactor system is proposed and demonstrated by using yolk-shell to enhance the performance of the chemical reaction. Mechanism studies show that the yolk-shell provides confined space to accelerate redox reaction kinetics;while the inner void promotes light harvesting and keeps yolk Cu_(2) O from deactivation;combined with the Z-scheme charge transfer, engineering Cu^(+) /Cu^(2+) active composition, they are favorable for enhancing the H_(2) O_(2) generation and Fenton-like activity. These findings provide new opportunities for application of yolk-shell Z-scheme metal-oxide-based photocatalysts.

关键词： Octahedron yolk-shell structure catalyzer Z-scheme charge transfer H2O_(2)generation Selective oxidation of BA Fenton-like reaction

Is the W-boson mass enhanced by the axion-like particle,dark photon,or chameleon dark energy?

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Science China(Physics,Mechanics & Astronomy) 2022年第12期65卷 145-152页

作者： Guan-Wen Yuan lei Zu Lei Feng Yi-Fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei230026China Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei230026China CAS Key Laboratory for Researches in Galaxies and Cosmology University of Science and Technology of ChinaHefei230026China

The W-boson mass(m W=(80.4335±0.0094)Ge V)measured by the Collider Detector at Fermilab Collaboration is greater than the standard model(SM)prediction at a confidence level of 7σ,strongly suggesting the presence of new particles or fields.In the literature,various new particles and/or fields have been introduced to explain the astrophysical and experimental data,and their presence,in principle,may also enhance the W-boson mass.In this study,we investigate axion-like particle(ALP),dark photon(DP),and chameleon dark energy(DE)models for a solution to the W-boson mass excess.We find that the ALP and DP interpretations have been significantly narrowed down by global electroweak fits.The possibility of attributing the W-boson mass anomaly to the chameleon DE is ruled out by other experiments.

关键词： W-boson mass axion-like particle dark photon chameleon dark energy

Autocrine motility factor receptor as a therapeutic target for asthma:comments on‘AMFR drives allergic asthma development by promoting alveolar macrophage-derived GM-CSF production’

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Journal of Molecular Cell Biology 2022年第5期14卷 57-59页

作者： Huihui Zhang feng Qian lei Sun Engineering Research Center of Cell&Therapeutic Antibody Ministry of EducationPharm-X CenterSchool of PharmacyShanghai Jiao Tong UniversityShanghai 200240China

Asthma is a chronic inflammatory disease characterized by airway hyper-responsiveness and tissue remodeling(Nobsetal.,2021).Although explorations into the pathogenesis of asthma are increasing,the underlying molecular and cellular mechanisms of asthma remain indistinct,and existing targeted therapy strategies are still limited and ineffective.

关键词： asthma allergic

H'-splittings of Seifert Manifolds with Boundary

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Acta Mathematica Sinica,English Series 2023年第4期39卷 695-706页

作者： Yan XU feng Chun lei feng Ling LI School of Mathematical Sciences Dalian University of TechnologyDalian 116024P.R.China

It is known that each compact connected orient able 3-manifold M with boundary admits an H’-splitting H1∪FH2,where F is a compact connected orientable surface properly embedded in M and splits M into two handlbodies H_(1) and H_(2).In this paper,we show that a non-completely L-reducible and minimal H’-splitting surface for a compact connected irreducible orientable anannular Seifert 3-manifold with boundary is horizontal,and give a necessary and sufficient condition for an amalgamation of two compact connected orientable 3-manifolds along a compact connected surface to be a Seifert manifold with boundary,and describe a characteristic of some H’-splittings to denote a Seifert 3-manifold with boundary.For a compact connected orientable Seifert manifold M with a semi-bundle structure M_(1)∪_(F)M_(2),we give an upper bound of the genus of the base surface.

关键词： Seifert manifold H'-splitting vertical or horizontal surface amalgamated 3-manifold

Multiscale observation in wide-spatial radar surveillance based on coherent FDA design

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Science China(Information Sciences) 2024年第2期67卷 232-252页

作者： lei YU feng HE Yi SU College of Electronics Science National University of Defense Technology

Wide-spatial radar surveillance missions are challenging tasks, requiring an increased power budget and agility in transmission aimed at extracting information from multiple targets in different environments. These requirements necessitate high transmitting degrees of freedom(DOF) to achieve the objective of multiscale observation for specific tasks in specialized regions of interest. Herein, we exploit the multiscale observation ability in wide-spatial radar surveillance based on frequency diverse array(FDA)radar. The proposed method facilitates spatial anisotropic control of multiple radar resources, including the transmitting waveforms, beampattern, and bandwidth. By utilizing a coherent FDA radar, we offer principles for the selection of baseband waveforms, in addition to the quantitative design of the beampattern gain and optimal bandwidth from the perspective of detection. The feasibility of the proposed method is validated through numerical experiments, thus indicating the potential in wide-spatial radar surveillance. Moreover,this work can be regarded as a preliminary attempt to gauge the efficacy of the computational array, a novel academic concept.

关键词： multi-scale observation wide-spatial surveillance frequency diverse array (FDA) beampattern synthesis frequency diversity gain computational array

The driving force of water resource stress change based on the STIRPAT model:take Zhangye City as a case study

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Research in Cold and Arid Regions 2021年第4期13卷 337-348页

作者： Xia Tang XinYuan Wang Lei Feng Key Laboratory of Ecohydrology of Inland River Basin Chinese Academy of SciencesLanzhouGansu 730000China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhouGansu 730000China Ecological Environmental Supervision and Administration Bureau of Gansu Province LanzhouGansu 730020China Gansu Computing Center LanzhouGansu 730030China

A prominent contradiction between supply and demand of water resources has restricted local development in social and economic aspects of Zhangye City,located in a typical arid region of China.Our study quantified the Water Resource Stress Index(WRSI)from 2003 to 2017 and examined the factors of population,urbanization level,GDP per capita,Engel coefficient,and water consumption per unit of GDP by using the extended stochastic impact by regression on population,affluence and technology(STIRPAT)model to find the key factors that impact WRSI of Zhangye City to relieve the pressure on water resources.The ridge regression method is applied to improve this model to eliminate multicollinearity problems.The WRSI system was developed from the following three aspects:water resources utilization(WR),regional economic development water use(WU),and water environment stress(WE).Results show that the WRSI index has fallen from 0.81(2003)to 0.17(2017),with an average annual decreased rate of 9.8%.Moreover,the absolute values of normalized coefficients demonstrate that the Engel coefficient has the largest positive contribution to increase WRSI with an elastic coefficient of 0.2709,followed by water consumption per unit of GDP and population with elastic coefficients of 0.0971 and 0.0387,respectively.In contrast,the urbanization level and GDP per capita can decrease WRSI by−0.2449 and−0.089,respectively.The decline of WRSI was attributed to water-saving society construction which included the improvement of water saving technology and the adjustment of agricultural planting structures.Furthermore,this study demonstrated the feasibility of evaluating the driving forces affecting WRSI by using the STIRPAT model and ridge regression analysis.

关键词： water resource stress index STIRPAT model driving force analysis water scarcity

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN lei HU Rong feng LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Phylogenomic cytonuclear discordance and evolutionary histories of plants and animals

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Science China(Life Sciences) 2023年第12期66卷 2946-2948页

作者： lei Duan Lin Fu Hong-feng Chen Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China South China National Botanical Garden Guangzhou 510650China

The field of evolutionary biology has been revolutionized by phylogenomic approaches in the last decades. However, with the ever-increasing size and scope of molecular data collection, conflicting genealogies may be yielded based on different datasets and analytical approaches, a phenomenon known as cytonuclear discordance(Figure 1A and B).

关键词： Figure discord size

Multi-legged robots: progress and challenges

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National Science Review 2023年第5期10卷 16-18页

作者： Yue Gao Bo Su lei Jiang feng Gao Mo E Key Lab of Artificial Intelligence AI InstituteShanghai Jiao Tong University China North Artificial Intelligence and Innovation Research Institute State Key Laboratory of Mechanical System and Vibration School of Mechanical Engineering Shanghai Jiao Tong University

Considerable attention has been focused on multi-legged robots,with progress being made in the areas of mechanical design,actuators,controls,planning,and learning-based methods,as shown in Fig.1.Legged robots are multi-input,multi-output,multi-end-effector systems.Hence,they are challenging to control when traversing unstructuredenvironments.In recent years,

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