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Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

中国晶体学会第六届学术年会暨会员代表大会（极端条件晶体材料分会）

作者： F.Sun g.Q.Zhao C.A.Escanhoela Jr. B.J.Chen R.H.Kou Y.g.wang Y.M.Xiao P.Chow H.K.Mao D.Haskel w.g.yang C.Q.Jin Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Advanced Photon Source Argonne National Laboratory Center for High Pressure Science & Technology Advanced Research (HPSTAR) Collaborative Innovation Center of Quantum Matter

we investigate doping-and pressure-induced changes in the electronic state of Mn 3d and As4p orbitals in Ⅱ-Ⅱ-V based diluted magnetic semiconductor(Ba,K)(Zn,Mn)Asto shed light into the mechanism of indirect exchange...

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality wood vibration performance Paulownia wood Machine learning methods

Origins of perturbations in dayside equatorial ground magnetograms

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Earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun w.Hsieh David g.Sibeck The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA NASA goddard Space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,*** examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local *** those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to *** results show that an equivalent number of events were identified for each model during this 90-day *** in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the *** in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

Superconductivity Bordering Rashba Type Topological Transition

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Superconductivity Bordering Rashba Type Topological Transiti...

Overview of radar detection methods for low altitude targets in marine environments

中国晶体学会第六届学术年会暨会员代表大会（极端条件晶体材料分会）

作者： M.L.Jin F.Sun L.Y.Xing S.J.Zhang S.M.Feng P.P.Kong w.M.Li X.C.wang J.L.Zhu Y.w.Long H.Y.Bai C.Z.gu R.C.Yu w.g.yang g.Y.Shen Y.S.Zhao H.K.Mao C.Q.Jin Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences HiPSEC Department of Physics and AstronomyUniversity of Nevada at Las Vegas High Pressure Synergetic Consortium (HPSynC) & High Pressure Collaborative Access Team (HPCAT) Geophysical LaboratoryCarnegie Institution of Washington Center for High Pressure Science & Technology Advanced Research (HPSTAR)

Strong spin orbital interaction(SOI)can induce unique quantum phenomena such as topological insulators,the Rashba effect,or p-wave *** these three quantum phenomena into a single compound has important scientific *** ...

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： yang Yong yang Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath *** performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Coupled Cu doping and Z-scheme heterojunction for synergistically enhanced tetracycline photodegradation

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Nano Research 2024年第7期17卷 5937-5948页

作者： Huidong Shen Chunming yang Song Hong Leiduan Hao Liang Xu Alex w.Robertson Zhenyu Sun Country State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China Department of Physics University of WarwickCoventry CV 47ALUK

Semiconductor-based photocatalysis by utilizing solar energy for sustainable organic pollutant elimination has been a promising tactic to alleviate environmental ***,the development of robust and efficient photocatalysts to degrade organic pollutants still faces major challenges because of insufficient charge *** we design and fabricate a heterojunction consisting of copper,carbon-modified TiO_(2),and sulfur-doped g-C_(3)N_(4)nanosheets(i.e.,S-C_(3)N_(4)/Cu/C-TiO_(2)).The heterostructure affords a remarkable synergistic photocatalysis for tetracycline hydrochloride degradation,achieving an 82.6%removal efficiency within 30 min under visible light irradiation,about 15.4 and 7.3 times higher than that of S-C_(3)N_(4)and C-TiO_(2),*** superior performance is attributed to the synergy between Cu doping and the Z-scheme heterojunction,which not only enhances the interfacial electric field effect,facilitating charge separation,but also boosts the redox *** charge carrier transfer between Cu/C-TiO_(2)and S-C_(3)N_(4)follows a Z-scheme,as verified by trapping experiments,electron spin-resonance spectroscopy,and density functional theory ***,the tetracycline hydrochloride degradation pathways are enunciated by liquid chromatograph mass spectrometry *** work provides an effective approach for constructing high-performance photocatalysts that have potential in environmental remediation.

关键词： photocatalysis Cu doping Z-scheme heterojunction electrons and holes separation tetracycline degradation

Selective nano-buckling improves the performance of graphene logic transistors

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National Science Review 2024年第2期11卷 95-96页

作者： Tong yang Ming yang Department of Applied Physics The Hong Kong Polytechnic University Research Centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

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Microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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Journal of Materials Science & Technology 2024年第4期171卷 80-93页

作者： Y.H.Zhang H.Li Z.w.yang X.Liu Q.F.gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.with increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy wide transformation hysteresis Thermomechanical loading Microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning