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Rapid post-earthquake safety assessment of low-rise reinforced concrete structures

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 101-112页

作者： Koji Tsuchimoto Yasutaka Narazaki Billie f.Spencer,Jr. International Design Division Design DepartmentTaisei CorporationTokyo 163-0606Japan Zhejiang University–University of Illinois Urbana-Champaign Institute Zhejiang UniversityHaining 314400China Civil and Environmental Engineering University of Illinois Urbana-ChampaignUrbana 61821USA

Many countries throughout the world have experienced large earthquakes,which cause building damage or *** such earthquakes,structures must be inspected rapidly to judge whether they are safe to *** facilitate the inspection process,the authors previously developed a rapid building safety assessment system using sparse acceleration measurements for steel framed *** proposed system modeled nonlinearity in the measurement data using a calibrated simplified lumped-mass model and convolutional neural networks(CNNs),based on which the buildinglevel damage index was estimated rapidly after *** proposed system was validated for a nonlinear 3D numerical model of a five-story steel building,and later for a large-scale specimen of an 18-story building in Japan tested on the E-Defense shaking ***,the applicability of the safety assessment system for reinforced concrete(RC)structures with complex hysteretic material nonlinearity has yet to be explored;the previous approach based on a simplified lumpedmass model with a Bouc-Wen hysteretic model does not accurately represent the inherent nonlinear behavior and resulting damage states of RC *** study extends the rapid building safety assessment system to low-rise RC moment resisting frame structures representing typical residential apartments in ***,a safety classification for RC structures based on a damage index consistent with the current state of practice is ***,a 3D nonlinear numerical model of a two-story moment frame structure is created.A simplified lumped-mass nonlinear model is developed and calibrated using the 3D model,incorporating the Takeda degradation model for the RC material *** model is used to simulate the seismic response and associated damage sensitive features(DSf)for random ground *** resulting database of responses is used to train a convolutional neural network(CNN)that performs rapid safety ***

关键词： rapid post-earthquake safety assessment acceleration interstory drift angle damage sensitive feature convolutional neural network RC structure simplified non-linear analysis model Takeda degradation model

Energy Meteorology for the Evaluation of Solar farm Thermal Impacts on Desert Habitats

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ADVANCES IN ATMOSPHERIC SCIENCES 2025年第2期42卷 313-326页

作者： Coimbra, Carlos f. M. Univ Calif San Diego Ctr Excellence Renewable Resource Integrat Jacobs Sch Engn Dept Mech & Aerosp Engn La Jolla CA 92093 USA Univ Calif San Diego Ctr Energy Res La Jolla CA 92093 USA

This work addresses challenges and opportunities in the evaluation of solar power plant impacts, with a particular focus on thermal effects of solar plants on the environment and vice-versa. Large-scale solar power plants are often sited in arid or desert habitats, which tend to include fauna and flora that are highly sensitive to changes in temperature and humidity. Our understanding of both shortwave (solar) and longwave (terrestrial) radiation processes in solar power plants is complete enough to render the modeling of radiation fluxes with high confidence for most applications. In contrast to radiation, the convective environment in large-scale solar power plants is much more difficult to characterize. Wind direction, wind speed, turbulence intensity, dust concentration, ground condition, panel configuration density, orientation and distribution throughout the solar field, all affect the local environment, the balance between radiation and convection, and in turn, the performance and thermal impact of solar power plants. Because the temperatures of the two sides of photovoltaic (PV) panels depend on detailed convection-radiation balances, the uncertainty associated with convection affects the heat and mass transfer balances as well. Those balances are critically important in estimating the thermal impact of large-scale solar farms on local habitats. Here we discuss outstanding issues related with these transfer processes for utility-scale solar generation and highlight potential pathways to gain useful knowledge about the convective environment directly from solar farms under operating conditions. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)

关键词： environmental impact solar farms thermal balances shortwave and longwave radiation convection (sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)

Magnitude, spatial patterns and drivers of methane fluxes from coastal salt marshes and mangrove forests in China

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Science China Earth Sciences 2025年第3期68卷 850-866页

作者： Yixuan YU Derrick Y.f.LAI Minjie HU Chuan TONG Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education Fujian Normal University School of Geographical Sciences Fujian Normal University Department of Geography and Resource Management The Chinese University of Hong Kong

Methane（CH4） is a highly potent greenhouse gas due to its high radiative forcing and global warming *** the magnitude, spatial patterns, and drivers of CH4emission from wetlands at the regional scale is crucial for formulating suitable strategies to mitigate future climate change. In this study, we synthesized the CH4flux data reported for major plant communities in the coastal salt marshes and mangrove forests in China and produced a spatial map of CH4fluxes from the mangrove sediments and salt marshes in China based on the results of machine learning models. Moreover, we examined the main drivers of CH4flux from these coastal wetlands and estimated the annual CH4emissions from the salt marshes and mangrove forests in different coastal provinces of China using a bottom-up approach. Our results showed that the mean CH4fluxes from the salt marsh and mangrove ecosystems in China were 2.22±0.29 and 2.26±0.55 mg m-2h-1, respectively. Across China, the total annual CH4emission from salt marshes was 31,179.75 Mg CH4a-1, while that from mangroves was 5,533.97 Mg CH4a-1with the sediments contributing to 12.7%(701.64 Mg CH4a-1) of the total efflux. The salt marshes and mangroves in China accounted for 2.75% and 0.14%–0.15% of the global annual CH4emissions from these two ecosystems,respectively. Moreover, we found that CH4emissions from the salt marshes and mangroves could offset the cooling impact arising from net carbon dioxide uptake by 88% and 53%, respectively, over a 100-year time scale. Mean annual temperature, soil moisture, and soil organic carbon content were the main factors controlling CH4emissions from these coastal ***, we found that CH4fluxes from the salt marshes in China decreased with latitude, which implied a possible increase in marsh CH4emission in response to global warming that should be considered carefully when developing nature-based climate solutions to achieve national goals for carbon neutrality.

关键词： Salt marsh Mangrove Methane flux Spatial pattern Driving factors China

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Energy Meteorology for the Evaluation of Solar farm Thermal Impacts on Desert Habitats

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Advances in Atmospheric Sciences 2025年第02期 313-326页

作者： Carlos f.M.COIMBRA Department of Mechanical and Aerospace Engineering Jacobs School of Engineering Center of Excellence in Renewable Resource Integration and Center for Energy Research University of California San Diego

This work addresses challenges and opportunities in the evaluation of solar power plant impacts, with a particular focus on thermal effects of solar plants on the environment and vice-versa. Large-scale solar power plants are often sited in arid or desert habitats, which tend to include fauna and flora that are highly sensitive to changes in temperature and humidity. Our understanding of both shortwave(solar) and longwave(terrestrial) radiation processes in solar power plants is complete enough to render the modeling of radiation fluxes with high confidence for most applications. In contrast to radiation, the convective environment in large-scale solar power plants is much more difficult to characterize. Wind direction, wind speed, turbulence intensity, dust concentration, ground condition, panel configuration density, orientation and distribution throughout the solar field, all affect the local environment, the balance between radiation and convection,and in turn, the performance and thermal impact of solar power plants. Because the temperatures of the two sides of photovoltaic(PV) panels depend on detailed convection–radiation balances, the uncertainty associated with convection affects the heat and mass transfer balances as well. Those balances are critically important in estimating the thermal impact of large-scale solar farms on local habitats. Here we discuss outstanding issues related with these transfer processes for utility-scale solar generation and highlight potential pathways to gain useful knowledge about the convective environment directly from solar farms under operating conditions.

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Anomalous open orbits in Hofstadter spectrum of Chern insulator

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Science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah f.Q.Yuan Hua Jiang Haiwen Liu X.C.Xie Center for Advanced Quantum Studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematics UC Berkeley Institute for Nanoelectronic Devices and Quantum Computing Fudan University International Center for Quantum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of Chern insulator can enrich the content of its Hofstadter butterfly spectra, which is closely related to recent experiments in twisted bilayer graphene and cold atom systems. We investigate the Hofstadter spectrum for various models of Chern insulators under a rational flux φ0/q, here φ0=h/e and q being an integer. We find the number of splitting subbands is |q-C| with C denoting the Chern number of parent band. Importantly, anomalous open-orbital subbands with Chern numbers q-1 and-q-1 emerge unexpectedly, which are beyond the parameter window（-q/2, q/2） of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum, identifying as a new type of topological phase transition. These novel findings not only pinpoint the peculiar Hofstadter spectrum of Chern insulator, but also provide routes to study exotic characteristics beyond the Landau level physics.

关键词： Hofstadter spectrum topological phase transition open orbit

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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 120-127页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal UniversityShanghai 200241China Institute of Acoustics Tongji UniversityShanghai 200092China L.V.Kirensky Institute of Physics Krasnoyarsk 660036Russia Department of Mechanical Engineering Rowan UniversityGlassboro 08028USA School of Engineering and Technology University of New South Wales at CanberraACT 2610Australia

Bound states in the continuum(BICs)are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional toΔL^(−4),whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective non-Hermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

fake Studies fake scientific studies are a problem that’s getting harder to solve

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空中英语教室(高级版.彭蒙惠英语) 2025年第1期 12-13,41,42页

作者： f.D.flam 不详

faking it until you make it may be a common practice in some *** it's clearly unethical for scientists and medical *** the same,thousands of fake papers are churned out by so-called paper mills and published every yea... 详细信息

关键词： s. problem getting

Effects of rare-earth Pr3+-Dy3+ doping on structural,magnetic,optical and dielectric properties of Zn2Y hexaferrite

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Journal of Rare Earths 2025年第2期43卷 329-336页

作者： Ibrahim Mohammed Mohamed E.El Sayed Ali Shawabkeh Mohammad N.Murshed Ibtehaj f.Alshdoukhi Zeinhom M.El-Bahy J.Mohammed A.K.Srivastava Department of Physics Lovely Professional University Department of Science Technology Waziri Umaru Federal Polytechnic Birnin Kebbi Physics Department Faculty of Science and ArtsKing Khalid University College of Engineering and Technology American University of the Middle East Department of Basic Sciences College of Science and Health ProfessionsKing Saud Bin Abdulaziz University for Health ScienceKing Abdullah International Medical Research Center Department of Chemistry Faculty of ScienceAl-Azhar University Department of Physics Faculty of ScienceFederal University Dutse

This study was conducted to investigate the properties of Pr3+-Dy3+doped Zn2Y-type hexaferrite for potential technological applications.X-ray diffraction（XRD）,fourier transform infrared spectroscopy（fTIR） and field-emission scanning electron microscopy（fESEM） were used to analyze structural *** crystallite size in the synthesized samples varies between 57.54 and 68.57 *** vibrational bands at 400 and 600 cm-1,common to all hexaferrites,were confirmed through *** fESEM analysis reveals an agglomeration of magnetic grains and a decrease in the average grain size from 1.24 to1.06 μ*** M-H loops show that,with x values of 0.0,0.1,and 0.2,the saturation magnetization is determined to be 34.76,34.23,and 32.52 emu/g,*** corresponding coercivity values are21.24,30.39,and 33.99 ***-visible spectroscopy using Tauc theory reveals an increase in the optical band gap from 2.32 to 2.50 eV,indicating a tunable energy band structure by incorporating Pr3+-Dy3+*** dielectric constant increases,whereas AC conductivity decreases with increased Pr3+-Dy3+*** obtained results suggest the potential suitability of these materials for various technological applications.

关键词： Dielectric constant Magnetic hysteresis Optical band gap Pr3+-Dy3+ Rare earths Zn2Y-type hexaferrite

Iron-promoted zirconia-alumina supported Ni catalyst for highly efficient and cost-effective hydrogen production via dry reforming of methane

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Journal of Environmental Sciences 2025年第2期148卷 274-282页

作者： Ahmed S.Al-fatesh Naitik Patel Vijay Kumar Srivastava Ahmed I.Osman David W.Rooney Anis H.fakeeha Ahmed E.Abasaeed Mohammed f.Alotibi Rawesh Kumar Chemical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia Department of Chemistry Indus UniversityAhmedabadGujarat 382115India School of Chemistry and Chemical Engineering Queen’s University BelfastBelfast BT95AGNorthern IrelandUK Institute of Refining and Petrochemicals Technologies King Abdulaziz City for Science and Technology(KACST)P.O.Box 6086Riyadh 11442Kingdom of Saudi Arabia

Developing cost-effective and high-performance catalyst systems for dry reforming of methane(DRM)is crucial for producing hydrogen(H_(2))***,we investigate using iron(fe)as a promoter and major alumina support in Ni-based catalysts to improve their DRM *** addition of iron as a promotor was found to add reducible iron species along with reducible NiO species,enhance the basicity and induce the deposition of oxidizable *** incorporating 1 wt.%fe into a 5Ni/10ZrAl catalyst,a higher CO_(2) interaction and formation of reducible"NiO-species having strong interaction with support"was observed,which led to an∼80%H_(2) yield in 420 min of Time on Stream(TOS).further increasing the fe content to 2 wt.%led to the formation of additional reducible iron oxide species and a noticeable rise in H_(2) yield up to 84%.Despite the severe weight loss on fe-promoted catalysts,high H_(2) yield was maintained due to the proper balance between the rate of CH_(4) decomposition and the rate of carbon deposit ***,incorporating 3 wt.%fe into the 5Ni/10ZrAl catalyst resulted in the highest CO_(2) interaction,wide presence of reducible NiO-species,minimumgraphitic deposit and an 87%H_(2) *** findings suggest that ironpromoted zirconia-alumina-supported Ni catalysts can be a cheap and excellent catalytic system for H_(2) production via DRM.

关键词： Dry reforming of methane Coke resistant Hydrogen production Cheap catalyst fe-promoted catalyst