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Evaluation of Leaf Spectra(150-1100 nm)in Tetraploid Rice and Their Spontaneously Reverted Diploid Counterparts 认领 引用
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作者 Árpád SZÉKELY Tímea SZALÓKI +2 位作者 Ildiko KOLOZSVÁRI Aftab JAMAL Mihály JANCSÓ 《Rice science》 SCIE CAS CSCD 2026年第3期292-296,I0171-I0182,共5页
The objective of this study was to examine the spectral differences between tetraploid rice and their spontaneously reverted diploid counterparts under field conditions.No significant absorption advantage was observed... The objective of this study was to examine the spectral differences between tetraploid rice and their spontaneously reverted diploid counterparts under field conditions.No significant absorption advantage was observed for tetraploid rice in the visible and near-infrared regions(NIR);however,they consistently exhibited higher absorption in the ultraviolet(UV)range across years and for all 2n-4n pairs.The most pronounced and significant differences were identified as follows:at 190-193 nm,215-220 nm,249-253 nm,281-283 nm,293-295 nm,308-312 nm,and 332 nm during the seedling stage,and at 382 nm during the reproductive stage. 展开更多
关键词 tetraploid rice spontaneously reverted diploid leaf spectra ultraviolet range visible near infrared regions seedling stage spectral differences spontaneously reverted diploid counterparts
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Single-scan ultra-selective probing on targeted components from overlapped NMR spectra 认领 引用
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作者 Haolin Zhan Liangliang Hu +1 位作者 Yuqing Huang Zhong Chen 《Magnetic Resonance Letters》 EI CAS 2026年第2期69-79,共11页
Benefitting from the non-invasive and quantitative detection property,liquid NMR spectroscopy shows broad applications in the identification,separation,and structural determination of chemical substances in mixtures.H... Benefitting from the non-invasive and quantitative detection property,liquid NMR spectroscopy shows broad applications in the identification,separation,and structural determination of chemical substances in mixtures.However,its applications,especially to probing complex mixtures that contain abundant components and complicated molecular structures,somewhat encounter the challenge of spectral congestion.In this study,we demonstrate the ultra-selective extraction of targeted components from overlapped NMR spectra for mixture analyses by investigating the applications of the recent 1D selective GEMSTONE-TOCSY approach.This strategy first adopts an ultra-selective chemical shift filter to choose the targeted spins related to the components of interest,even though situated at overlapped spectral regions with decent suppression on unwanted surrounding signals.Sequentially,it utilizes the 1D selective TOCSY scheme to accurately extract total coupling networks associated with targeted spins,and then spectroscopically separate individual components,thus resolving overlapped NMR spectra.Apart from the measurements on electrolyte and sugar mixtures,experimental results demonstrate that it also allows one to analyze heterogeneous biological tissues containing plentiful metabolites and intrinsic field inhomogeneity via specific probe access to targeted components.Therefore,this study demonstrates a useful tool for component analyses and molecular structure measurements on complex chemical and biological mixtures,and it shows promising prospects for wide applications in the fields of chemistry,biology,energy,etc. 展开更多
关键词 NMR spectroscopy Ultra-selective chemical shift filter Targeted component probing Overlapped spectra Heterogeneous sample detection
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Advances in parasitic peaks suppression for surface waves investigation and monitoring wave spectra based on the improved signal-to-noise ratio threshold method 认领 引用
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作者 Jingwei Gu Bosen Jiang +4 位作者 Yijun He Yuelin Zhang Baochang Liu Xinhua Zhao Shuyan Lang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2026年第3期174-184,共11页
The retrieval accuracy of ocean wave spectra from the surface waves investigation and monitoring(SWIM)instrument aboard the China-France Oceanography Satellite is significantly compromised by the presence of parasitic... The retrieval accuracy of ocean wave spectra from the surface waves investigation and monitoring(SWIM)instrument aboard the China-France Oceanography Satellite is significantly compromised by the presence of parasitic peaks.In the latest version of SWIM data,a signal-to-noise ratio threshold method(SNRTM)is implemented to suppress parasitic peaks.A homogeneous signal-to-noise ratio(SNR)threshold across all wavenumbers is set in this method.However,the distribution characteristics of parasitic peaks exhibit strong wavenumber dependence—obvious in low wavenumbers and not obvious in high wavenumbers.In addition,the performance of SNRTM is sensitive to the selected SNR threshold.Therefore,a homogeneous SNR threshold is not precise enough.To address these challenges,we propose an improved SNRTM.This method segments wavenumbers according to the severity of parasitic peaks,followed by the construction of individual cost functions within each segment.By minimizing these cost functions,the most appropriate SNR thresholds can be obtained.The results demonstrate that the improved SNRTM achieves enhanced spectral quality across all wavenumbers,with notable improvements in the estimation of wave parameters.The proposed method can provide critical data support for oceanography and climate modeling applications by mitigating noises in satellite-derived wave spectra. 展开更多
关键词 SWIM wave spectra parasitic peaks signal-to-noise ratio
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Energy-resolved in-source dissociation spectra by tunable pulsed arc plasma ionization for the differentiation of structural isomers 认领 引用
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作者 Ming-Mai Bao Ying-Chao Liu +2 位作者 Hao-Nan Xu Jing Zhang Yin-Long Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第6期765-771,共7页
Differentiating structural isomers in mass spectrometry(MS)poses significant challenges due to the difficulties in generating fragment ions by atmospheric pressure ionization and the spectral similarities encountered ... Differentiating structural isomers in mass spectrometry(MS)poses significant challenges due to the difficulties in generating fragment ions by atmospheric pressure ionization and the spectral similarities encountered in tandem MS/MS analysis.The continuous arc plasma enables in-source dissociation fingerprinting analysis of isomers but presents a risk of solvent ignition during sample introduction because of high temperatures,posing safety concerns.To address these challenges,the tunable pulsed arc plasma(TPAP)ionization and dissociation device has been developed.The TPAP device converts continuous arc plasma into a pulsed mode,reduces plasma temperatures,enhances discharge stability and safety,and enables adjustable plasma energy for in-source compound dissociation.Programmable control over the pulsed arc plasma voltage allows the scanning of compounds under varying dissociation energies,facilitates the construction of compound-specific energy-resolved spectra.Validation experiments with disubstituted benzene species,chlorogenic acid derivatives,disaccharide and diacylglycerol have demonstrated the capability of TPAP-MS to effectively differentiate isomers through distinct energy-resolved spectra.The TPAP-MS requires minimal instrumental modifications and provides rapid and precise structural annotations directly from the ion source,offering broad potential applications in the analysis of structural isomers. 展开更多
关键词 Mass spectrometry Pulsed arc plasma Energy-resolved spectra Structural isomers
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Generalized Energy-Based Fragmentation TDDFT-ris Method and its Application to Electronic Spectra and Asymmetry Factors of Large Systems 认领 引用
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作者 Ziyi Lv Fengmin Wang +5 位作者 Junhui Sun Xuerong Wang Shuhua Li Zehao Zhou Jingxiang Zou Wei Li 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2026年第3期303-312,共10页
Accurately and efficiently calculating electronic excited states remains a major challenge in quantum chemistry,especially for complex photophysical and photochemical systems.Conventional approaches such as time-depen... Accurately and efficiently calculating electronic excited states remains a major challenge in quantum chemistry,especially for complex photophysical and photochemical systems.Conventional approaches such as time-dependent density functional theory(TDDFT)are limited by unfavorable computational scaling,limiting their applicability to large systems.To address this,we present a computational framework combining the generalized energy-based fragmentation(GEBF)approach with TDDFT-ris,which requires only one s-type auxiliary basis function per atom via the resolution-of-the-identity technique.This approach enables efficient and reliable excited-state computations for macromolecules,including fluorescent materials and proteins with thousands of atoms,and provides accurate predictions of asymmetry factors(g-factors)in chiral optoelectronic materials and fluorescent protein. 展开更多
关键词 Generalized energy-based fragmentation Time-dependent density functional theory Electronic spectra Asymmetry factor Fluorescent protein
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基于FPGA的Spectra 6全彩电子纸画面切换动态特效设计 认领 引用
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作者 卢晓光 房纪军 《信息技术与标准化》 2026年第3期18-23,共6页
针对Spectra 6全彩色电子纸刷新时全屏闪烁、自定义难、适配差等问题,提出基于FPGA的画面切换动态特效刷新方案。通过8 bit灰阶模板映射相位偏移,结合自研TCON硬件架构与双维度查表算法,实现图形化自定义与精准控制。实验表明,该方案闪... 针对Spectra 6全彩色电子纸刷新时全屏闪烁、自定义难、适配差等问题,提出基于FPGA的画面切换动态特效刷新方案。通过8 bit灰阶模板映射相位偏移,结合自研TCON硬件架构与双维度查表算法,实现图形化自定义与精准控制。实验表明,该方案闪烁度≤4 Hz、残影率≤0.8%,兼容多平台且局部功耗降40%以上,能够提升多场景体验。 展开更多
关键词 Spectra 6全彩色电子纸 FPGA TCON控制器 画面切换动态特效
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Central-Pixel Guiding Sub-Pixel and Sub-Channel Convolution Network for Hyperspectral Image Classification 认领 引用
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作者 Xin Guan Shan Wang Qiang Li 《Journal of Beijing Institute of Technology》 EI CAS 2025年第5期510-525,共16页
In hyperspectral image classification(HSIC),accurately extracting spatial and spectral information from hyperspectral images(HSI)is crucial for achieving precise classification.However,due to low spatial resolution an... In hyperspectral image classification(HSIC),accurately extracting spatial and spectral information from hyperspectral images(HSI)is crucial for achieving precise classification.However,due to low spatial resolution and complex category boundary,mixed pixels containing features from multiple classes are inevitable in HSIs.Additionally,the spectral similarity among different classes challenge for extracting distinctive spectral features essential for HSIC.To address the impact of mixed pixels and spectral similarity for HSIC,we propose a central-pixel guiding sub-pixel and sub-channel convolution network(CP-SPSC)to extract more precise spatial and spectral features.Firstly,we designed spatial attention(CP-SPA)and spectral attention(CP-SPE)informed by the central pixel to effectively reduce spectral interference of irrelevant categories in the same patch.Furthermore,we use CP-SPA to guide 2D sub-pixel convolution(SPConv2d)to capture spatial features finer than the pixel level.Meanwhile,CP-SPE is also utilized to guide 1D sub-channel con-volution(SCConv1d)in selecting more precise spectral channels.For fusing spatial and spectral information at the feature-level,the spectral feature extension transformation module(SFET)adopts mirror-padding and snake permutation to transform 1D spectral information of the center pixel into 2D spectral features.Experiments on three popular datasets demonstrate that ours out-performs several state-of-the-art methods in accuracy. 展开更多
关键词 hyperspectral image classification similar spectra mixed pixel attention
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A deep learning approach for enhanced degradation diagnostics of NMC lithium-ion batteries via impedance spectra 认领 引用 被引量：2
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作者 Yue Sun Rui Xiong +2 位作者 Peng Wang Hailong Li Fengchun Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2025年第8期894-907,共14页
Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short ... Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short in quantitatively determining the degree of specific degradation modes,which are essential for improving battery lifespan.This study introduces a novel approach employing deep neural networks enhanced by an attention mechanism to identify the degree of degradation modes.The proposed method can automatically determine the most relevant frequency ranges for each degradation mode,which can link impedance characteristics to battery degradation.To overcome the limitation of scarce labeled experimental data,simulation results derived from mechanistic models are incorporated into the model.Validation results demonstrate that the proposed method could achieve root mean square errors below 3%for estimating loss of lithium inventory and loss of active material of the positive electrode,and below 4%for estimating loss of active material of the negative electrode while requiring only 25%of early-stage experimental degradation data.By integrating simulation results,the proposed method achieves a reduction in maximum estimation error ranging from 42.92%to 66.30%across different temperatures and operating conditions compared to the baseline model trained solely on experimental data. 展开更多
关键词 Lithium-ion battery Degradation diagnostics Impedance spectra Integration strategy Deep learning
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Extraction of fissile isotope antineutrino spectra using feedforward neural network 认领 引用 被引量：1
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作者 Jian Chen Jun Wang +1 位作者 Wei Wang Yue-Huan Wei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2025年第10期13-23,共11页
The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrin... The precise measurement of the antineutrino spectra produced by isotope fission in reactors is of great significance for studying neutrino oscillations,refining nuclear databases,and addressing the reactor antineutrino anomaly.In this paper,we report a method that utilizes a feedforward neural network(FNN)model to decompose the prompt energy spectrum observed in a short-baseline reactor neutrino experiment and extract the antineutrino spectra produced by the fission of major isotopes such as235U,238U,239Pu,and241Pu in the nuclear reactor.We present two training strategies for the model and compare them with the traditional X2 minimization method by applying them to the same set of pseudo-data corresponding to a total exposure of(2.9×5×1800)GWth·tons·days.The results show that the FNN model not only converges faster and better during the fitting process but also achieves relative errors of less than 1%in the 2−8 MeV range in the extracted spectra,outperforming the X2 minimization method.The feasibility and superiority of this method were validated in the study. 展开更多
关键词 Reactor neutrinos Isotope antineutrino spectra Feedforward neural network
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Impact of assimilating buoy directional spectra on tropical cyclone wind-wave modeling:a case study of Isaias(2020) 认领 引用
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作者 Jincan Liu Yongjun Jia +2 位作者 Jie Ding Jiagen Wang Jichao Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2025年第10期244-270,共27页
This study applies Ensemble Optimal Interpolation(EnOI)to assimilate individual spectral components derived from National Data Buoy Center(NDBC)buoy directional spectra into the WAVEWATCHⅢ(WW3)wave model during tropi... This study applies Ensemble Optimal Interpolation(EnOI)to assimilate individual spectral components derived from National Data Buoy Center(NDBC)buoy directional spectra into the WAVEWATCHⅢ(WW3)wave model during tropical cyclone(TC)Isaias(2020).The analysis provides a comprehensive evaluation of the assimilation’s impact on wave parameters,frequency spectra,and directional spectra.Two series of assimilation experiments—one based on spectral components(Exp*-DaSpec)and the other on significant wave height(Exp*-DaSWH)—are evaluated against a non-assimilated control run(Exp-NoDa).Particular focus is placed on six key parameters:SWH,mean wave period(MWP),mean wave direction(MWD),mean wave directional spread(MWS),dominant wave period(DWP),and dominant wave direction(DWD).Sensitivity analyses suggest 400 km and 0.30 as appropriate values for the localization radius and observation error variance,respectively,though no single setting is optimal across all wave parameters.Exp4-DaSWH and Exp4-DaSpec are therefore selected as representative experiments.In non-independent validation,Exp4-DaSpec generally outperforms Exp-NoDa across MWP,MWD,MWS,DWP,and DWD,demonstrating closer agreement with observed frequency spectra and directional patterns.In independent validation,Exp4-DaSpec maintains superior overall performance,whereas Exp4-DaSWH shows only limited improvement.Exp4-DaSWH may capture the spectral peak near 0.1 Hz,although its directional characteristics remain largely similar to those of Exp-NoDa.Importantly,the assimilation experiments significantly improve SWH in both non-independent and independent validations,with Exp4-DaSWH slightly outperforming Exp4-DaSpec overall. 展开更多
关键词 tropical cyclone spectral component data assimilation buoy directional spectra wave modeling significant wave height
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Could Plant Height Compensate for Temporal and Spatial Limitations of Canopy Spectra for Inversion of Plant Nitrogen Accumulation in Rice? 认领 引用
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作者 WANG Xiaoke XU Guiling +7 位作者 FENG Yuehua SONG Zhengli GUO Yanjun Muhammad Usama LATIF LU Linya Somsana PHONENASAY XU Xiangjun CUI BingPing 《Rice science》 SCIE CSCD 2025年第4期467-471,I0037-I0042,共5页
Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in hor... Recently,information acquired at the canopy top,such as spectral and textural data,has been widely used to estimate plant nitrogen(N)accumulation(PNA).The response of crops to N uptake involves not only changes in horizontal canopy top information but also an increase in vertical plant height(PH).It remains unclear whether the fusion of spectral indices with PH can improve the estimation performance of PNA models based on spectral remote sensing across different growth stages. 展开更多
关键词 temporal limitations rice nitrogen accumulation canopy top information spatial limitations plant height spectral remote sensing canopy spectra
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Optimization of the prompt fission neutron spectra of 239Pu(n,f)via criticality benchmarking 认领 引用
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作者 Jia-Hao Chen Bo Yang +5 位作者 Qing-Gang Jia Rui Li Wen-Di Chen Hai-Rui Guo Wei-Li Sun Tao Ye 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2025年第9期139-149,共11页
Prompt fission neutron spectra(PFNS)have a significant role in nuclear science and technology.In this study,the PFNS for239Pu are evaluated using both differential and integral experimental data.A method that lever... Prompt fission neutron spectra(PFNS)have a significant role in nuclear science and technology.In this study,the PFNS for239Pu are evaluated using both differential and integral experimental data.A method that leverages integral criticality benchmark experiments to constrain the PFNS data is introduced.The measured central values of the PFNS are perturbed by constructing a covariance matrix.The PFNS are sampled using two types of covariance matrices,either generated with an assumed correlation matrix and incorporating experimental uncertainties or derived directly from experimental reports.The joint Monte Carlo transport code is employed to perform transport simulations on five criticality benchmark assemblies by utilizing perturbed PFNS data.Extensive simulations result in an optimized PFNS that shows improved agreement with the integral criticality benchmark experiments.This study introduces a novel approach for optimizing differential experimental data through integral experiments,particularly when a covariance matrix is not provided. 展开更多
关键词 Prompt fission neutron spectra Differential nuclear data Criticality benchmark Random sample Transport simulation
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Kolmogorov-Arnold networks modeling of wall pressure wavenumber-frequency spectra under turbulent boundary layers 认领 引用
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作者 Zhiteng Zhou Yi Liu +1 位作者 Shizhao Wang Guowei He 《Theoretical & Applied Mechanics Letters》 EI CAS CSCD 2025年第2期115-121,共7页
The empirical models for wavenumber-frequency spectra of wall pressure are broadly used in the fast prediction of aerodynamic and hydrodynamic noise.However,it needs to fit the parameter using massive data and is only... The empirical models for wavenumber-frequency spectra of wall pressure are broadly used in the fast prediction of aerodynamic and hydrodynamic noise.However,it needs to fit the parameter using massive data and is only used for limited cases.In this letter,we propose Kolmogorov-Arnold networks(KAN)base models for wavenumber-frequency spectra of pressure fluctuations under turbulent boundary layers.The results are compared with DNS results.In turbulent channel flows,it is found that the KAN base model leads to a smooth wavenumber-frequency spectrum with sparse samples.In the turbulent flow over an axisymmetric body of revolution,the KAN base model captures the wavenumber-frequency spectra near the convective peak. 展开更多
关键词 Wavenumber-frequency spectra Kolmogorov-Arnold networks modeling Turbulent boundary layers
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Anharmonic and Damped Correction to Displaced Franck-Condon Factors for Simulating Molecular Absorption and Fluorescence Spectra 认领 引用
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作者 Chaoyuan Zhu 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2025年第5期546-564,I0147,共19页
The anharmonic correction to displaced Franck-Condon(FC)factors introduces a first-order perturbative correction to the Huang-Rhys factors,enabling accurate simulation of vibronic spectra in the gas phase.In contrast,... The anharmonic correction to displaced Franck-Condon(FC)factors introduces a first-order perturbative correction to the Huang-Rhys factors,enabling accurate simulation of vibronic spectra in the gas phase.In contrast,the damped correction to displaced FC factors provides a non-perturbative modification to the Huang-Rhys factors for simulating vibronic spectra in solution,where the damped local-mode motions of the solute molecule effectively represent strong solute-solvent interactions.Practically,the damped FC method is implemented by transforming the mass-weighted unperturbed Hessian matrix(gas phase)into a perturbed Hessian matrix(solution phase)through effective scaling of atomic masses.The anharmonic FC method is applied to simulate the absorption and fluorescence spectra of the pyridine molecule.The results reveal an enhancement in absorption intensity and a corresponding weakening of fluorescence in the first excited state,which are in good agreement with experimental observations.The damped FC method is further employed to reproduce solvent-enhanced absorption and fluorescence spectra for perylene and carbazole molecules in solution.For perylene in benzene,a single-group mass-scaling parameter successfully reproduces the observed spectral enhancement.For carbazole in n-hexane,however,multiple-group mass-scaling parameters are required to capture the extremely enhanced spectral features.Overall,the present anharmonic and damped corrections to displaced Franck-Condon factors provide an analytically tractable and efficient framework for simulating vibronic spectra of large and complex molecular systems. 展开更多
关键词 Franck-Condon factors Molecular absorption and fluorescence spectra Huang-Rhys factors Solvent effects
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WITHDRAWAL:Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models 认领 引用
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《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2025年第2期625-625,共1页
WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphol... WITHDRAWAL:Zhang,J.J.,Guo,Y.Q.,Qin,Z.Y.,Wei,C.T.,Hu,Q.H.,Vandeginste,V.,Miao,H.Y.,Yao,P.,and Zhang,P.F.,“Predicting Irreducible Water Saturation of Unconventional Reservoirs by Using NMR T2 Spectra:Methods of Morphological Division and Fractal Models”,Acta Geologica Sinica-English Edition(Accepted Article):http://gffzzd3cc09b8251d45dfsoxk96f9w0bxk6nq5.ffgz.tsg.suse.edu.cn/10.1111/1755-6724.15094. 展开更多
关键词 fractal models morphological division nmr t spectra methods fractal models acta irreducible water saturation nmr t spectra
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Characterization and recognition of three-dimensional excitation-emission matrix spectra of wastewater from six typical categories 认领 引用 被引量：3
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作者 Litao Kuang Rui Liu +4 位作者 Meng Jin Yaqiong Lan Yingying Su Yuan Zhao Lujun Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2025年第11期206-219,共14页
In this study,we analyzed the characteristics of three-dimensional excitation-emission matrix spectra(EEMs)of 150 samples from five industrial wastewater types and domestic sewage to track water pollution sources effe... In this study,we analyzed the characteristics of three-dimensional excitation-emission matrix spectra(EEMs)of 150 samples from five industrial wastewater types and domestic sewage to track water pollution sources effectively.We then developed a recognition model for wastewater EEMs by establishing a feature dataset containing fluorescence peak values and parameters derived from EEMs,integrated with machine learning techniques.This model enables the rapid and precise identification of pollution sources.Our findings suggest that although the EEMs of the sixwastewater categories are distinct,visual differentiation is challenging.This was confirmed by cosine similarity assessments,showing some samples with low within-group(0.95)similarities.Despite significant variations in EEMs features acrosswastewater categories,identifying specific pollutants remains difficult,especially for pulp mills and leather effluents.Among the tested classification algorithms,Support Vector Machine(SVM)achieved the highest performance with91.7%accuracy,94%precision,91%recall,and 92%F1-score,outperforming K-Nearest Neighbors and Partial Least Squares Discriminant Analysis.The SVM significantly improved identification accuracy for pulpmill and leather processing wastewaters compared to other models.To enhance identification accuracy,further exploration of EEMs features and expanding the training dataset are recommended.Combining EEMs features with machine learning presents a promising method for improvingwater pollution supervision and source tracing in environmental management practices. 展开更多
关键词 Excitation-emission-matrix spectra Support vector machine K-nearest neighbor Industrial wastewater Domestic sewage Partial least squares discriminant analysis
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Non-specific/specific SERS spectra concatenation for precise bacteria classifications with few samples using a residual neural network 认领 引用
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作者 Feihu Wu Gengwen Chen +10 位作者 Kaitao Lai Shiqing Zhang Yingchao Liu Ruijian Luo Xiaocong Wang Pinzhi Cao Yi Ye Jiarong Lian Junle Qu Zhigang Yang Xiaojun Peng 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第1期484-490,共7页
Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amo... Deep learning neural network incorporating surface enhancement Raman scattering technique(SERS)is becoming as a powerful tool for the precise classifications and diagnosis of bacterial infections.However,the large amount of sample requirement and time-consuming sample collection severely hinder its applications.We herein propose a spectral concatenation strategy for residual neural network using nonspecific and specific SERS spectra for the training data augmentation,which is accessible to acquiring larger training dataset with same number of SERS spectra or same size of training dataset with fewer SERS spectra,compared with pure non-specific SERS spectra.With this strategy,the training loss exhibit rapid convergence,and an average accuracy up to 100%in bacteria classifications was achieved with50 SERS spectra for each kind of bacterium;even reduced to 20 SERS spectra per kind of bacterium,classification accuracy is still>95%,demonstrating marked advantage over the results without spectra concatenation.This method can markedly improve the classification accuracy under fewer samples and reduce the data collection workload,and can evidently enhance the performance when used in different machine learning models with high generalization ability.Therefore,this strategy is beneficial for rapid and accurate bacteria classifications with residual neural network. 展开更多
关键词 SERS Deep learning Resnet Bacteria classification Spectra concatenation
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Studies on the Electronic Structures and Spectra of C78(CH_2)_3 认领 引用 被引量：1
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作者 TENG Qi-Wen WU Shi CHEN Si-Cong 《Chinese Journal of Structural Chemistry》 SCIE CAS 北大核心 2007年第3期314-320,共7页
The structures and spectra of 20 possible isomers of C78（CH2）3 have been studied by using AMI, INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78（CH2）3 （A） with annulene st... The structures and spectra of 20 possible isomers of C78（CH2）3 have been studied by using AMI, INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78（CH2）3 （A） with annulene structures, where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 （C2v）. Compared with that of C78 （C2v）, the first absorption in the electronic spectrum of C78（CH2）3 （A） iS blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C-C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition. 展开更多
关键词 C78（CH2）3 DFT electronic spectra IR spectra NMR spectra
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Construction of Even-Variable 2-Output Almost Optimal Five-Valued Spectra Boolean Functions 认领 引用
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作者 SONG Chao-Fan JI Yan-Han SUN Yu-Juan 《密码学报（中英文）》 CSCD 北大核心 2025年第3期714-728,共15页
Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively ... Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively studied over the past few decades,there has been limited research on the construction of almost optimal five-valued spectra vectorial Boolean functions.In this paper,we present a construction method for even-variable 2-output almost optimal five-valued spectra balanced Boolean functions,whose Walsh spectra values belong to the set{0,±2n/2,±2n/2+1},at the same time,we discuss the existence of sufficient conditions in the construction.Additionally,this paper presents a novel construction method for balanced single-output Boolean functions with even variables featuring a special five-valued spectral structure,whose Walsh spectra values are constrained to the set{0,±2n/2,±3·2n/2}.These functions provide new canonical examples for the study of Boolean function spectral theory. 展开更多
关键词 Boolean function Walsh transform semi-bent function five-valued function totally disjoint spectra functions
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A time-dependent generalized Floquet calculation of the laser-induced lineshape in attosecond transient absorption spectra 认领 引用
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作者 Xu-Han Wang Di Zhao Peng-Bo Li 《Chinese Physics B》 SCIE EI CAS CSCD 2025年第11期359-367,共9页
We introduce a time-dependent generalized Floquet(TDGF)approach to calculate attosecond transient absorption spectra of helium atoms subjected to the combination of an attosecond extreme ultraviolet(XUV)pulse and a de... We introduce a time-dependent generalized Floquet(TDGF)approach to calculate attosecond transient absorption spectra of helium atoms subjected to the combination of an attosecond extreme ultraviolet(XUV)pulse and a delayed few-cycle infrared(IR)laser pulse.This TDGF approach provides a Floquet understanding of the laser-induced change of resonant absorption lineshape.It is analytically demonstrated that the phase shift of the time-dependent dipole moment that results in the lineshape changes consists of two components,the adiabatic laser-induced phase(LIP)due to the IR-induced Stark shifts of adiabatic Floquet states and the non-adiabatic phase correction due to the non-adiabatic IR-induced coupling between adiabatic Floquet states.Comparisons of the spectral lineshape calculated based on the TDGF approach with the results obtained with the LIP model[Phys.Rev.A 88033409(2013)]and the rotating-wave approximation(RWA)are presented for several typical cases,demonstrating that TDGF universally and accurately captures IR-induced lineshape changes.It is suggested that the LIP model works as long as the generalized adiabatic theorem[PRX Quantum 2030302(2021)]holds,and the RWA works when the higher-order IR-coupling effect in the formation of adiabatic Floquet states is neglectable. 展开更多
关键词 attosecond transient absorption spectra Floquet analysis non-adiabatic phase correction
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