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Methods and Practices for Institutional Benchmarking based on Research Impact and Competitiveness: A Case Study of ShanghaiTech University 被引量:5
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作者 Jiang Chang Jianhua Liu 《Journal of Data and Information Science》 CSCD 2019年第3期55-72,共18页
Purpose: To develop and test a mission-oriented and multi-dimensional benchmarking method for a small scale university aiming for internationally first-class basic research.Design/methodology/approach: An individualiz... Purpose: To develop and test a mission-oriented and multi-dimensional benchmarking method for a small scale university aiming for internationally first-class basic research.Design/methodology/approach: An individualized evidence-based assessment scheme was employed to benchmark ShanghaiTech University against selected top research institutions,focusing on research impact and competitiveness at the institutional and disciplinary levels.Topic maps opposing ShanghaiTech and corresponding top institutions were produced for the main research disciplines of ShanghaiTech. This provides opportunities for further exploration of strengths and weakness. Findings: This study establishes a preliminary framework for assessing the mission of the university. It further provides assessment principles, assessment questions, and indicators.Analytical methods and data sources were tested and proved to be applicable and efficient.Research limitations: To better fit the selective research focuses of this university, its schema of research disciplines needs to be re-organized and benchmarking targets should include disciplinary top institutions and not necessarily those universities leading overall rankings.Current reliance on research articles and certain databases may neglect important research output types.Practical implications: This study provides a working framework and practical methods for mission-oriented, individual, and multi-dimensional benchmarking that ShanghaiTech decided to use for periodical assessments. It also offers a working reference for other institutions to adapt. Further needs are identified so that ShanghaiTech can tackle them for future benchmarking.Originality/value: This is an effort to develop a mission-oriented, individually designed,systematically structured, and multi-dimensional assessment methodology which differs from often used composite indices. 展开更多
关键词 DIFFERENTIATING evaluation Mission-driven ASSESSMENT EVIDENCE-BASED ASSESSMENT BENCHMARKING Research performance
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High-throughput generation of aqueous two-phase microcapsules using microfluidic bubble triggering
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作者 Sixiang Rao Weiliang Zhi +4 位作者 Chengkai Hong Yanan Du Long Chen Yuan Luo Yifan Liu 《Droplet》 2026年第1期63-70,共8页
Hydrogel microcapsules are powerful microreactor vessels that have attracted widespread attention and research.Among the various methods for their generation,the aqueous two-phase system(ATPS)is by far the most straig... Hydrogel microcapsules are powerful microreactor vessels that have attracted widespread attention and research.Among the various methods for their generation,the aqueous two-phase system(ATPS)is by far the most straightforward approach.However,the high viscosity of ATPS solutions significantly limits the generation throughput of hydrogel microcapsule.In this study,we developed a novel high-throughput approach for generating hydrogel microcapsules using a microfluidic bubble-triggering strategy.By integrating constant-pressure air flow with droplet microfluidics devices,we efficiently manipulated the formation of ATPS droplet through bubble-induced Rayleigh-Plateau instability,enabling the production of uniform,monodisperse microcapsules.Additionally,the droplet generation frequency in the bubble-triggering method exceeded 36 kHz.We further demonstrated the encapsulation of genetically engineered Escherichia coli strains,which acted as biosensors for arsenic ions and caprolactam,highlighting the potential of these microcapsules for biosensing applications.This advancement in hydrogel microcapsule generation offers promising implications for scalable applications in biosensing,organoid culture,and high-throughput screening. 展开更多
关键词 aqueous two phase system hydrogel microcapsules generating hydrogel microcapsules biosensing applications microreactor vessels Rayleigh Plateau instability high throughput generation microfluidic bubble triggering
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Mitigating emittance and longitudinal profile degradation of non-ideal bunches caused by CSR in multi-bend deflecting beamlines
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作者 Xiu-Ji Chen Si Chen +1 位作者 Hai-Xiao Deng Dong Wang 《Nuclear Science and Techniques》 2026年第3期50-64,共15页
Preserving beam quality during the transport of high-brightness electron bunches is crucial for advanced accelerator applications,such as particle colliders,free-electron lasers,and recirculating linacs.However,cohere... Preserving beam quality during the transport of high-brightness electron bunches is crucial for advanced accelerator applications,such as particle colliders,free-electron lasers,and recirculating linacs.However,coherent synchrotron radiation(CSR)significantly degrades beam quality when electron bunches pass through multi-bend isochronous beamlines,particularly for short bunches with non-ideal longitudinal profiles.Although several methods have been proposed to mitigate CSR effects,most rely on small-angle approximations or are limited to idealized bunch profiles.In this study,we present two improved methods for designing isochronous triple-bend achromat(TBA)beamlines that effectively mitigate CSR-induced emittance growth and longitudinal profile distortion without relying on small-angle approximations.The first method,an enhanced integral optimization approach,simplifies numerical optimization and can accurately handle larger deflection angles,making it suitable for practical applications that require flexible lattice configurations.The second method,an optimized I-matrix approach,completely cancels steady-state and transient CSR kicks through specific matrix constraints and higher-order dispersion optimization,enabling effective CSR suppression even with very large deflection angles.Systematic simulations demonstrate that both methods achieve excellent preservation of transverse emittance and longitudinal profiles. 展开更多
关键词 Lattice design Coherent synchrotron radiation Horizontal emittance
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Pressure-Enhanced Intrinsic Anomalous Hall Conductivity in the Kagome Ferrimagnet TbMn_(6)Sn_(6)
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作者 Hao Sun Jiabin Qiao +13 位作者 Weian Guo Pengyu Zheng Yuwei Liu Pengda Ye Yuemei Li Shucui Sun Deng Hu Yongkai Li Yanpeng Qi Zhiwei Wang Meiling Jin Jie Chen Zhiping Yin Xiang Li 《Chinese Physics Letters》 2026年第3期102-117,共16页
The kagome ferrimagnet TbMn_(6)Sn_(6),featuring a pristine Mn kagome lattice,has emerged as a candidate Chern magnet with a large intrinsic anomalous Hall effect(AHE).While chemical substitution can modulate its prope... The kagome ferrimagnet TbMn_(6)Sn_(6),featuring a pristine Mn kagome lattice,has emerged as a candidate Chern magnet with a large intrinsic anomalous Hall effect(AHE).While chemical substitution can modulate its properties,hydrostatic pressure provides a disorder-free route to manipulate electronic and magnetic interactions.Herein,we investigate the effects of hydrostatic pressure on electrical and magneto-transport in TbMn6Sn6 up to 18.3 GPa.Pressure significantly enhances hysteresis in the magnetoresistance and Hall responses,causing a concurrent monotonic coercive field increase,suggesting the enhancement of interlayer magnetic couplings in a robust c-axis ferrimagnetic order.The intrinsic anomalous Hall conductivity increases considerably from 129.5 S·cm^(−1) at ambient pressure conditions to 448.7 S·cm^(−1) at 14.0 GPa—an enhancement of 247%that is unprecedented among pressure-tuned kagome magnets.Based on density functional theory calculations,we reveal that pressure induces multiple gap openings near the Fermi level,giving rise to pronounced Berry curvature hotspots that may contribute to the AHE.Our results show that pressure can be used to enhance the intrinsic topological responses of this kagome magnet. 展开更多
关键词 chern magnet mn kagome latticehas anomalous hall effect ahe enhances hysteresis magnetoresistance kagome ferrimagnet chemical substitution hydrostatic pressure manipulate electronic magnetic interactionshereinwe
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Cell-autonomous determination of sex dimorphism in neuromodulation of a gynandromorphic Zebra Finch
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作者 Yangyang Cao Zhiwen Huang +5 位作者 Wenxiang Hu Yutao Zhang Kun Zhang Jiachun Zuo Yan Zou Wei Meng 《Avian Research》 2026年第1期157-171,共15页
Gynandromorphs,rare in vertebrates,exhibit distinct sex-determining gene expression on each side of the body despite sharing a uniform hormonal environment.This provides a unique opportunity to investigate the respect... Gynandromorphs,rare in vertebrates,exhibit distinct sex-determining gene expression on each side of the body despite sharing a uniform hormonal environment.This provides a unique opportunity to investigate the respective roles of genes and hormones in sex determination.We accidently obtained a gynandromorphic Zebra Finch with a male-female chimeric appearance but only with an ovary-like gonad.Its plasma estradiol was significantly higher than that of age-matched females,and its sexual partner preference was also feminine.Although it did not sing like males,its calls showed masculinization.In the brain on one side of the body with male plumage,the area of song motor nucleus,the robust nucleus of the arcopallium(RA),and the excitatory synaptic transmission of RA projection neurons showed masculinization.Transcriptome analysis revealed that genes related to cholinergic neuron function were significantly upregulated in the masculinized side of brain.Moreover,there were extensive and consistent expression differences of neuroactive substance receptor genes in both sides of body,indicating that cell-autonomous determination plays a key role in sex dimorphism of neuromodulation. 展开更多
关键词 AVIAN Cell-autonomous determination GYNANDROMORPH NEUROMODULATION Sex dimorphism Sex hormone Synaptic transmission Zebra Finch
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Estimating genetic load from 5000 Chinese exomes
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作者 Xiaoyue Du Xiaoxi Zhang +2 位作者 Jiucun Wang Li Jin Shuhua Xu 《Journal of Genetics and Genomics》 2026年第3期401-413,共13页
Recent advancements in genome sequencing have enabled the estimation of genetic load through deleterious mutation profiling.However,Chinese populations remain underexplored in this context.We analyze whole-exome seque... Recent advancements in genome sequencing have enabled the estimation of genetic load through deleterious mutation profiling.However,Chinese populations remain underexplored in this context.We analyze whole-exome sequencing data from 5002 individuals,encompassing major Han subgroups―North Han(NHan),South Han(S-Han),and Guangxi Han(G-Han)―as well as 13 ethnic minorities.Notably,G-Han exhibits significant genetic affinity with the Zhuang population.Systematic curation of 2110 ClinVar pathogenic or likely pathogenic variants reveals 93.4%are ultra-rare.Exceptions include GJB2 rs72474224-A(hearing loss),which shows higher frequencies in Zhuang and G-Han,and β-thalassemia-associated HBB variants(rs33986703-A and rs33950507-T),which are elevated in G-Han compared to other Han subgroups.Among 96 autosomal dominant mutation carriers,LDLR variants are predominant(~25%),with comparable frequencies across Han subgroups.Adaptive signatures highlight gene-environment interactions:MTHFR rs1801133-A(UV adaptation)declines southward,while ALDH2 rs671-A(alcohol metabolism)displays the opposite trend.ABCC11 rs17822931-A,associated with cold adaptation,is particularly low frequency in G-Han.Gene-based rare-variant collapsing analyses identify an elevated risk of retinitis pigmentosa in S-Han(PRPF4,TUB).Our findings demonstrate that genetic load in Chinese populations is influenced by demographic history,population structure,and regional adaptation,emphasizing the importance of population-specific frameworks in precision medicine. 展开更多
关键词 Genetic load Whole exome sequencing Rare variants CHINESE Ethnic stratification
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Single-Atom Ru in CoFe-LDH Drives Efficient Charge Separation on BiVO_(4) for Solar Water Splitting
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作者 Wenhui Deng Gaoshuang He +7 位作者 Haozhi Zhou Wenhao He Lei Gan Chenyu Zhang Keke Wang Xiaoqing Qiu Yang Liu Wenzhang Li 《Nano-Micro Letters》 2026年第6期840-854,共15页
Bismuth vanadate(BiVO_(4))is regarded as a promising photoanode for photoelectrochemical(PEC)water splitting.Despite its advantage in band gap and visible-light response,the BiVO_(4)exhibits an unsatisfactory achievin... Bismuth vanadate(BiVO_(4))is regarded as a promising photoanode for photoelectrochemical(PEC)water splitting.Despite its advantage in band gap and visible-light response,the BiVO_(4)exhibits an unsatisfactory achieving water splitting due to severe charge recombination.Herein,we elucidate an innovative approach involving the incorporation of single Ru atom with a CoFe-LDH cocatalyst(Ru_(0.51)-CoFe-LDH)and integrating it onto the BiVO_(4)semiconductor substrate.The resulting Ru_(0.51)-CoFe-LDH/BiVO_(4)photoanode film demonstrates commendable charge injection efficiency(76%)and charge collection efficiency(100%).Interestingly,the yield of hydrogen and oxygen increases linearly at a stoichiometric ratio of about 2:1,reaching 158.6 and 67.4μmol after140 min of irradiation,respectively.According to experimental characterization and density functional theory calculation,this remarkable performance results from single Ru atoms triggering the electron rearrangement of Ru_(0.51)-CoFe-LDH to engineer active sites and optimize interfacial energetics.Additionally,the negative shift of Ru_(0.51)-CoFe-LDH band edge gives rise to more conspicuous band bending of the n-n junction formed with BiVO_(4),expediting the separation and transfer of photogenerated electron-hole pairs at the interface.This work furnishes a new preparation perspective for PEC water splitting systems to construct single atoms in the semiconductor substrate. 展开更多
关键词 Photo-electrocatalysis Water splitting BiVO_(4)photoanode Ruthenium single atoms Layered double hydroxide
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Ultrahigh Dielectric Permittivity of a Micron-Sized Hf_(0.5)Zr_(0.5)O_(2) Thin-Film Capacitor After Missing of a Mixed Tetragonal Phase
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作者 Wen Di Zhang Bing Li +3 位作者 Wei Wei Wang Xing Ya Wang Yan Cheng An Quan Jiang 《Nano-Micro Letters》 2026年第1期144-153,共10页
Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received wides... Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received widespread applications in high-storage-density dynamic random access memory and energy-efficient complementary metal-oxide-semiconductor devices.During bipolar high electric-field cycling in numbers close to dielectric breakdown,the dielectric permittivity suddenly increases by 30 times after oxygen-vacancy ordering and ferroelectric-to-nonferroelectric phase transition of near-edge plasma-treated Hf_(0.5)Zr_(0.5)O_(2) thin-film capacitors.Here we report a much higher dielectric permittivity of 1466 during downscaling of the capacitor into the diameter of 3.85μm when the ferroelectricity suddenly disappears without high-field cycling.The stored charge density is as high as 183μC cm^(−2) at an operating voltage/time of 1.2 V/50 ns at cycle numbers of more than 10^(12) without inducing dielectric breakdown.The study of synchrotron X-ray micro-diffraction patterns show missing of a mixed tetragonal phase.The image of electron energy loss spectroscopy shows the preferred oxygen-vacancy accumulation at the regions near top/bottom electrodes as well as grain boundaries.The ultrahigh dielectric-permittivity material enables high-density integration of extremely scaled logic and memory devices in the future. 展开更多
关键词 Hf_(0.5)Zr_(0.5)O_(2)thin film Ultrahigh dielectric permittivity Near-edge plasma treatment Oxygen vacancy Charge storage
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Multifaceted Role of RIMBP2 in Promoting Hearing in Murine Cochlear Hair Cells
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作者 Menghui Liao Xin Chen +13 位作者 Ling Lu Qing Liu Rongrong Guo Yuyang Qiu Yangnan Hu Yuhua Zhang Qiaojun Fang Panpan Zhang Yige Li Shuijin He Mingliang Tang Huawei Li Geng-Lin Li Renjie Chai 《Neuroscience Bulletin》 2026年第2期270-284,共15页
The mammalian cochlea relies on outer and inner hair cells(OHCs/IHCs)for sound amplification and signal transmission.Rab3-interacting molecular binding protein 2(RIMBP2),expressed in receptor cells and neurons at syna... The mammalian cochlea relies on outer and inner hair cells(OHCs/IHCs)for sound amplification and signal transmission.Rab3-interacting molecular binding protein 2(RIMBP2),expressed in receptor cells and neurons at synaptic active zones,remains poorly characterized in hearing.We therefore generated a Rimbp2 knockout(KO)mouse model(Rimbp^(2-/-)),which exhibited severe hearing loss with elevated thresholds,prolonged latencies,and reduced amplitudes in auditory brainstem response Wave I.OHC loss via apoptosis was correlated with threshold elevation.In IHCs,patch-clamp recordings revealed reduced exocytosis,including a diminished readily-releasable pool,impaired sustained release,and blocked fast endocytosis.Immunostaining showed unchanged ribbon synapse numbers but positional shifts in the basal pole of KO IHCs.These findings demonstrated RIMBP2’s essential role in OHC survival and its broader regulatory functions in IHC synaptic transmission than previously recognized. 展开更多
关键词 RIMBP2 HEARING Hair cell Apoptosis Ribbon synapse EXOCYTOSIS
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Graphene Aerogel Composites with Self‑Organized Nanowires‑Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption 被引量:1
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作者 Xiao You Huiying Ouyang +6 位作者 Ruixiang Deng Qiuqi Zhang Zhenzhong Xing Xiaowu Chen Qingliang Shan Jinshan Yang Shaoming Dong 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期533-547,共15页
With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave absorbers.Herein,a hierarchical porous structure and composite h... With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave absorbers.Herein,a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss capacity.The macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires(SiC_(nws))grown in situ,while boron nitride(BN)interfacial structure is introduced on graphene nanoplates.The unique composite structure forces multiple scattering of incident EMWs,ensuring the combined effects of interfacial polarization,conduction networks,and magnetic-dielectric synergy.Therefore,the as-prepared composites present a minimum reflection loss value of−37.8 dB and a wide effective absorption bandwidth(EAB)of 9.2 GHz(from 8.8 to 18.0 GHz)at 2.5 mm.Besides,relying on the intrinsic high-temperature resistance of SiC_(nws) and BN,the EAB also remains above 5.0 GHz after annealing in air environment at 600℃ for 10 h. 展开更多
关键词 Hierarchical porous structure Interface High-temperature resistance Graphene aerogel composites Electromagnetic wave absorption
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Gamma-induced positron beam generation at SLEGS 被引量:1
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作者 Sheng Jin Zi-Rui Hao +8 位作者 Long-Xiang Liu Kai-Jie Chen Yu-Xuan Yang Hang-Hua Xu Yue Zhang Qian-Kun Sun Zhen-Wei Wang Gong-Tao Fan Hong-Wei Wang 《Nuclear Science and Techniques》 2025年第5期1-10,共10页
Energy-variable gamma-rays are produced in Laser Compton Slant-scattering mode at the Shanghai Laser Electron Gamma Source(SLEGS),a beamline of the Shanghai Synchrotron Radiation Facility(also called Shanghai Light So... Energy-variable gamma-rays are produced in Laser Compton Slant-scattering mode at the Shanghai Laser Electron Gamma Source(SLEGS),a beamline of the Shanghai Synchrotron Radiation Facility(also called Shanghai Light Source).Based on the SLEGS energy-variable gamma-ray beam,a positron generation system composed of a gamma-ray-driven section,positron-generated target,magnet separation section and positron experimental section was designed for SLEGS.Geant4 simulation results show that the energy tunable positron beam in the energy range of 1–12.9 MeV with a flux of 3.7×10^(4)–6.9×10^(5)e^(+)∕s can be produced in this positron generation system.The positron beam generation and separation provide favorable experimental conditions for conducting nondestructive positron testing on SLEGS in the future.The positron generation system is currently under construction and will be completed in 2025. 展开更多
关键词 Shanghai Laser Electron Gamma Source Monte Carlo simulation Nondestructive testing POSITRON GEANT4
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Ion-modulation optoelectronic neuromorphic devices:mechanisms,characteristics,and applications 被引量:1
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作者 Xiaohan Meng Runsheng Gao +1 位作者 Xiaojian Zhu Run-Wei Li 《Journal of Semiconductors》 2025年第2期24-36,共13页
The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorph... The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field. 展开更多
关键词 ion migration optoelectronic modulation optoelectronic device neuromorphic computing artificial vision system
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Enhancing reliability in photonuclear cross-section fitting with Bayesian neural networks 被引量:1
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作者 Qian-Kun Sun Yue Zhang +8 位作者 Zi-Rui Hao Hong-Wei Wang Gong-Tao Fan Hang-Hua Xu Long-Xiang Liu Sheng Jin Yu-Xuan Yang Kai-Jie Chen Zhen-Wei Wang 《Nuclear Science and Techniques》 2025年第3期146-156,共11页
This study investigates photonuclear reaction(γ,n)cross-sections using Bayesian neural network(BNN)analysis.After determining the optimal network architecture,which features two hidden layers,each with 50 hidden node... This study investigates photonuclear reaction(γ,n)cross-sections using Bayesian neural network(BNN)analysis.After determining the optimal network architecture,which features two hidden layers,each with 50 hidden nodes,training was conducted for 30,000 iterations to ensure comprehensive data capture.By analyzing the distribution of absolute errors positively correlated with the cross-section for the isotope 159Tb,as well as the relative errors unrelated to the cross-section,we confirmed that the network effectively captured the data features without overfitting.Comparison with the TENDL-2021 Database demonstrated the BNN's reliability in fitting photonuclear cross-sections with lower average errors.The predictions for nuclei with single and double giant dipole resonance peak cross-sections,the accurate determination of the photoneutron reaction threshold in the low-energy region,and the precise description of trends in the high-energy cross-sections further demonstrate the network's generalization ability on the validation set.This can be attributed to the consistency of the training data.By using consistent training sets from different laboratories,Bayesian neural networks can predict nearby unknown cross-sections based on existing laboratory data,thereby estimating the potential differences between other laboratories'existing data and their own measurement results.Experimental measurements of photonuclear reactions on the newly constructed SLEGS beamline will contribute to clarifying the differences in cross-sections within the existing data. 展开更多
关键词 Photoneutron reaction Bayesian neural network Machine learning Gamma source SLEGS
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Advances on Chiral Phosphoric Acid Catalyzed Asymmetric Electrophilic Amination Reactions
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作者 Tang Mengyao Yang Xiaoyu 《有机化学》 北大核心 2025年第6期1785-1818,共34页
The catalytic enantioselective electrophilic amination reaction has emerged as a highly efficient method for synthesizing diverse nitrogen-containing chiral molecules,with the development of various asymmetric catalys... The catalytic enantioselective electrophilic amination reaction has emerged as a highly efficient method for synthesizing diverse nitrogen-containing chiral molecules,with the development of various asymmetric catalysis systems.Chiral phosphoric acids(CPA)have been widely acknowledged as versatile chiral organocatalysts since it was first discovered in 2004,finding application in catalyzing diverse asymmetric reactions.A comprehensive overview of recent advances in CPA-catalyzed asymmetric electrophilic amination reactions using different N-electrophilic reagents,including azo reagents,aryldiazonium salts,and imine derivatives,is presented.Furthermore,insights into future developments in this field are offered. 展开更多
关键词 chiral phosphoric acid electrophilic amination AZODICARBOXYLATE asymmetric catalysis ORGANOCATALYSIS
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Hierarchical porous SiC_(nws)/SiC composites with one-dimensional oriented assemblies for high-temperature broadband wave absorption 被引量:1
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作者 Huiying Ouyang Xiao You +6 位作者 Yuanhang Yang Meihan Ren Qiuqi Zhang Ruixiang Deng Xiangyu Zhang Jinshan Yang Shaoming Dong 《Journal of Materials Science & Technology》 2025年第11期1-10,共10页
The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(S... The research on high-performance electromagnetic wave absorption materials with high-temperature and oxidative stability in extreme environments is gaining popularity.Herein,the lightweight silicon carbide nanowires(SiC_(nws))/SiC composites are fabricated with in-situ SiC interface on one-dimensional oriented SiC_(nws)skeleton,which collaborative configuration by 3D printing and freeze casting assembly.The con-structed porous structure optimizes the impedance matching degree and scattering intensity,the maximum effective absorption bandwidth(EAB_(max))of 5.9 GHz and the minimum reflection loss(RL_(min))of−41.4 dB can be realized.Considering the inherent oxidation resistance of SiC,the composites present well-maintained absorption performance at 600℃.Even at 1100℃,the EAB_(max)of 4.9 GHz and RLmin of−30.4 dB also demonstrate the high-temperature absorption stability of the composites,indicating exceptional wave absorption properties and thermal stability.The slight attenuation can be attributed to the decrease in impedance matching capability accompanying the elevated dielectric constant.This work clarifies the impact of structure and component synergy on wave absorption behavior,and offers a novel approach to producing high-performance and high-temperature resistance ceramic-based electromagnetic wave absorption materials suitable for extreme environments. 展开更多
关键词 Electromagnetic wave absorption Porous structure INTERFACE SiC_(nws)/SiC composites High-temperature resistance
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CO_(2)-free hydrogen production from solar-driven photothermal catalytic decomposition of methane 被引量:1
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作者 Yihan Zheng Yuxin Wang +6 位作者 Ruitao Li Haoran Yang Yuanyuan Dai Qiang Niu Tiejun Lin Kun Gong Liangshu Zhong 《Chinese Journal of Catalysis》 2025年第6期289-299,共11页
CO_(2)-free H_(2)refers to H_(2)production process without CO_(2)emission,which is a promising clean energy in the future.Catalytic decomposition of methane(CDM)is a competitive technology to produce CO_(2)-free H2 wi... CO_(2)-free H_(2)refers to H_(2)production process without CO_(2)emission,which is a promising clean energy in the future.Catalytic decomposition of methane(CDM)is a competitive technology to produce CO_(2)-free H2 with large-scale.However,CDM reaction is highly endothermic and is kinetically and thermodynamically unfavorable,which typically requires a harsh reaction temperature above 800℃.In this work,solar-driven photothermal catalytic decomposition of methane was firstly introduced to produce CO_(2)-free H_(2)relying solely on solar energy as the driving force.A high H_(2)yield of 204.6 mmol g^(–1)h^(–1)was observed over Ni-CeO2 interface under photothermal conditions,along with above 87%reduction in the apparent activation energy(11.2 vs.87.3 kJ mol^(–1))when comparing with the traditional thermal catalysis.Further studies suggested that Ni/CeO_(2)catalyst enhanced optical absorption in visible-infrared region to ensure the heat energy for methane decomposition.The generated electrons and holes participated in the redox process of photo-driven CDM reaction with enhanced separation ability of hot carriers excited by ultraviolet-visible light,which lowered activation energy and improved the photothermal catalytic activity.This work provides a promising photothermal catalytic strategy to produce CO_(2)-free H^(2)under mild conditions. 展开更多
关键词 CO_(2)-free hydrogen Hydrogen production Photothermal catalysis Methane decomposition Methane conversion
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CuI/4-Hydroxy Picolinohydrazide Catalyzed Coupling Reaction of(Hetero)aryl Chlorides with Sodium Aryl Sulfinates
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作者 Li Sailuo Ma Dawei 《有机化学》 北大核心 2025年第4期1276-1282,共7页
By using a newly developed 4-hydroxy picolinohydrazide as the ligand,Cu-catalyzed coupling of(hetero)aryl chlorides with sodium aryl sulfonates proceeded smoothly at 130℃to give a series of biarylsulfones in 53%~96%y... By using a newly developed 4-hydroxy picolinohydrazide as the ligand,Cu-catalyzed coupling of(hetero)aryl chlorides with sodium aryl sulfonates proceeded smoothly at 130℃to give a series of biarylsulfones in 53%~96%yields.This represents the first metal-catalyzed coupling reaction of(hetero)aryl chlorides with sodium aryl sulfonates.Aryl and heteroaryl chlorides bearing either electron-donating or electron-withdrawing groups were applicable for this coupling reaction. 展开更多
关键词 coupling reaction copper catalysis LIGAND (hetero)aryl chloride biarylsulfone
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Unsaturated cobalt single-atoms stabilized by silanol nests of zeolites for efficient propane dehydrogenation 被引量:1
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作者 Liwen Guo Dao Shi +4 位作者 Tianjun Zhang Yanhang Ma Guodong Qi Jun Xu Qiming Sun 《Chinese Journal of Catalysis》 2025年第5期323-333,共11页
Propane dehydrogenation(PDH)has emerged as a key on-purpose technology for the production of propylene,but it often depends on toxic chromium and expensive platinum catalysts,highlighting the need for environmentally ... Propane dehydrogenation(PDH)has emerged as a key on-purpose technology for the production of propylene,but it often depends on toxic chromium and expensive platinum catalysts,highlighting the need for environmentally friendly and cost-effective alternatives.In this study,we developed a facile impregnation method to fabricate unsaturated Co single-atoms with a tricoordinated Co_(1)O_(3)H_(x) structure by regulating silanol nests in purely siliceous Beta zeolites.Detailed PDH catalytic tests and characterizations revealed a positive correlation between the presence of silanol nests and enhanced catalytic activity.Additionally,the unsaturated Co single-atoms exhibited a carbon deposition rate more than an order of magnitude slower than that of Co nanoparticles.Notably,the optimized Co_(0.3%)/deAl-meso-Beta catalyst achieved a record-high propylene formation rate of 21.2 mmol_(C3H6) g_(cat)^(-1) h^(-1),with an exceptional propylene selectivity of 99.1%at 550℃.Moreover,the Co_(0.3%)/deAl-meso-Beta catalyst demonstrated excellent stability,with negligible deactivation after 5 consecutive regeneration cycles.This study emphasizes the pivotal role of silanol nests of zeolites in stabilizing and modulating the coordination environment of metallic active sites,providing valuable insights for the design of high-activity,high-stability,and low-cost PDH catalysts. 展开更多
关键词 Propane dehydrogenation Unsaturated cobalt Single-atoms Silanol nest Zeolite
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Photocatalytic C−C coupling of acetonitrile into succinonitrile over hydrophobic TiO_(2) in a flow reactor
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作者 GONG Kun HUANG Min +4 位作者 LI Ruitao DAI Yuanyuan NIU Qiang LIN Tiejun ZHONG Liangshu 《燃料化学学报(中英文)》 北大核心 2025年第12期1807-1816,共10页
A radical C−C-coupling reaction of acetonitrile into succinonitrile over hydrophobic TiO_(2) photocatalyst with enhanced catalytic activity was developed.In addition,the usage of a flow reactor further improved the ph... A radical C−C-coupling reaction of acetonitrile into succinonitrile over hydrophobic TiO_(2) photocatalyst with enhanced catalytic activity was developed.In addition,the usage of a flow reactor further improved the photon utilization efficiency for succinonitrile synthesis at room temperature.The space time yield of succinonitrile reached 55.59μmol/(g·h)over hydrophobic TiO_(2) catalyst,which was much higher than that of pristine TiO_(2)(4.23μmol/(g·h)).Mechanistic studies revealed that the hydrophobic modification of TiO_(2) promoted the separation and transfer of photogenerated carriers,as well as suppressed their recombination.Hydrophobic TiO_(2) also enhanced the adsorption of−CH3 of acetonitrile,thus facilitating the activation of C−H bond and the utilization efficiency of photocarriers. 展开更多
关键词 photocatalysis SUCCINONITRILE C−C coupling hydrophobic TiO_(2) flow reactor
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Large language model for interview-based depression diagnosis:an empirical study
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作者 Pengbo Hu Hong Li +2 位作者 Xingyu Li Chunxiao Li Yi Zhou 《中国科学技术大学学报》 北大核心 2025年第7期50-57,49,I0002,共10页
The automatic diagnosis of depression plays a crucial role in preventing the deterioration of depression symptoms.The interview-based method is the most wildly adopted technique in depression diagnosis.However,the siz... The automatic diagnosis of depression plays a crucial role in preventing the deterioration of depression symptoms.The interview-based method is the most wildly adopted technique in depression diagnosis.However,the size of the collected conversation data is limited,and the sample distributions from different participants usually differ drastically.These factors present a great challenge in building a decent deep learning model for automatic depression diagnosis.Recently,large language models have demonstrated impressive capabilities and achieved human-level performance in various tasks under zero-shot and few-shot scenarios.This sheds new light on the development of AI solutions for domainspecific tasks with limited data.In this paper,we propose a two-stage approach that exploits the current most capable and cost-effective language model,ChatGPT,to make a depression diagnosis on interview-based data.Specifically,in the first stage,we use ChatGPT to summarize the raw dialogue sample,thereby facilitating the extraction of depression-related information.In the second stage,we use ChatGPT to classify the summarised data to predict the depressed state of the sample.Our method can achieve approximately 76%accuracy with a text-only modality on the DAIC-WOZ dataset.In addition,our method outperforms the performance of the state-of-the-art model by 6.2%in the D4 dataset.Our work highlights the potential of using large language models for diagnosis-based depression diagnosis. 展开更多
关键词 depression diagnosis language model deep learning
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