A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam qualit...A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.展开更多
Electrochemical impedance spectroscopy(EIS)was used to examine the electrical properties of metakaolin(MK)cement-based materials at elevated temperatures.We utilized a new equivalent circuit to investigate the EIS res...Electrochemical impedance spectroscopy(EIS)was used to examine the electrical properties of metakaolin(MK)cement-based materials at elevated temperatures.We utilized a new equivalent circuit to investigate the EIS results of cementitious materials blended with MK at these temperatures.A new evaluation method to high temperature damage is proposed.The findings show that both elevated temperatures and MK contents in cement mortar can impact the impedance spectra’s form properties.However,the residual compressive strength of the MK-blended cementitious material at elevated temperatures does not improve with the addition of MK.A quantitative relationship between the electrochemical parameters of the new equivalent circuit and the residual compressive strength is determined.The degree of high-temperature damage to cementitious materials can be evaluated based on these electrochemical parameters,providing a new approach for evaluating the high-temperature damage of MK-blend cementitious materials.展开更多
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge...Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.展开更多
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni...The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility.展开更多
Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements hav...Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm.展开更多
This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source...This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source with 26 mm period,provides an operable energy range between 2.1 keV and 16 keV,covering the K-edges of P to Rb and L3-edges of Zr to Bi.The principal optical elements of the beamline are a toroidal mirror,a liquid nitrogen-cooled double-crystal monochromator,a high-harmonic-rejection mirror,and two pairs of Kirkpatrick–Baez(KB)mirrors.Three end-stations,including non-focusing,microprobe,and sub-microprobe types,are installed on the beamline.X-ray fluorescence(XRF)and X-ray absorption spectroscopy(XAS),including X-ray absorption near-edge structure(XANES)and extended X-ray absorption fine structure(EXAFS),are performed under vacuum or He atmosphere at the non-focusing end-station(with a beam spot size of∼670μm×710μm).Using two KB mirrors systems,micro-XRF(μXRF)mapping and micro-XANES(μXANES)studies can be performed with a spot size of approximately∼3.3μm×1.3μm at the microprobe end-station and with a smaller spot size of∼0.5μm×0.25μm at the sub-microprobe end-station.The non-focusing end-station was officially opened to users in January 2024.The microprobe and sub-microprobe end-stations will be opened to users in the near future.This paper presents the characteristics,short-term technical developments,and early experimental results of this new beamline.展开更多
Optical monitoring of fireballs can provide reconstructions of luminous trajectories and the derivation of heliocentric orbits,whereas spectral observations are able to supply information from an entirely different pe...Optical monitoring of fireballs can provide reconstructions of luminous trajectories and the derivation of heliocentric orbits,whereas spectral observations are able to supply information from an entirely different perspective,with composition and material data.Observing and analyzing a fireball by using both methods enables a complete characterization of its meteorite properties.We simultaneously collected luminous and spectral observations of fireballs through observation networks established in eastern China and the Western Cape of South Africa.The optical observations utilized 180°×180°fisheye cameras,whereas spectral data were recorded by fixing gratings in front of each camera lens on the Allsky7 instrument so that both could monitor fireballs within an all-sky field of view.The spectra had an effective resolution of R=200.During the first year of operation,the network detected spectra from 150 fireballs,most of which recognized at least Mg I and Na I emission lines,and both the spectra and trajectory were recorded for some.Preliminary analysis of four bright fireballs indicated they could be categorized as asteroidal orbits or Halley-type cometary orbits,with spectra classified as normal,Fe-rich,iron,and Na-poor,respectively.One Halley-type fireball belonged to the Perseid meteor shower.For the two fireballs on asteroid-like orbits,orbital comparisons with known near-Earth asteroids were performed using multiple D-criteria(orbital similarity functions).Under the D_(N)criterion,SAFB20250713(iron type)showed a loose possible match with 2021 BD,whereas JsFB20250110(Fe-rich type)exhibited a closer potential similarity with 2017 BK(D_(N)=0.03).Overall,the orbital comparison indicated possible associations but no definitive parent bodies,whereas the spectral characteristics were broadly consistent with the asteroid-like or comet-like nature implied by their orbital classes.展开更多
With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall e...With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall economic benefits.Based on the varietal characteristics of‘Zhouhua 5’and addressing practical issues in peanut production,this paper summarized key techniques for high-yield and high-efficiency film mulching cultivation of this variety.These techniques cover all critical stages,including land preparation and fertilization,seed preparation,sowing methods,field management,and timely harvesting,providing technical guidance for varietal promotion and peanut production.展开更多
Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating th...Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating this condition.Nevertheless,considering the vast amount of research that is currently being conducted,focusing on the utilization of TCM in the management of myopia,there is an urgent requirement for a thorough and comprehensive review.The review would serve to clarify the practical applications of TCM within this specific field,and it would also aim to elucidate the underlying mechanisms that are at play,providing a deeper understanding of how TCM principles can be effectively integrated into modern medical practices.Here,some modern medical pathogenesis of myopia and appropriate TCM techniques studies are summarized in the prevention and treatment of myopia.Further,we discussed the potential mechanisms and the future research directions of TCM against myopia.Identifying these mechanisms is crucial for understanding how TCM can be effectively utilized in this context.The combination of various TCM methods or the combination of traditional Chinese and Western medicine is of great significance for the prevention and control of myopia in the future.展开更多
Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance ...Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks.展开更多
In this paper,a fast step heterodyne light-induced thermoelastic spectroscopy(SH-LITES)sensor using a high-frequency quartz tuning fork(QTF)with resonant frequency of~100 kHz is reported for the first time.The theoret...In this paper,a fast step heterodyne light-induced thermoelastic spectroscopy(SH-LITES)sensor using a high-frequency quartz tuning fork(QTF)with resonant frequency of~100 kHz is reported for the first time.The theoretical principle of heterodyne LITES(H-LITES)signal generation is analyzed firstly,and an acetylene(C_(2)H_(2))H-LITES sensor is established to verify its performance.Experimental comparisons between the high-frequency QTF and a standard commercial QTF with resonant frequency of~32.768 kHz reveal that the high-frequency QTF exhibits a tenfold faster response time.Specifically,the H-LITES sensor with this QTF achieves a 33 ms measurement cycle,90%shorter than commercial counterparts.Furthermore,The SH-LITES technique is proposed to further shorten the scanning time to 15 ms,which achieves the shortest LITES measurement time known to date.To demonstrate its advantages in dynamic gas detection,an H_(2)O-LITES system integrating both QTF types is constructed for real-time monitoring of H_(2)O concentration during different respiration patterns.Comparative measurements show that the SH-LITES more accurately captures dynamic H_(2)O concentration fluctuations during respiration,outperforming the commercial QTF-based H-LITES sensor in rapid response scenarios.展开更多
The increasing power density of chips poses a significant challenge in the form of material aging for aluminumfilled polydimethylsiloxane(Al/PDMS)composites,which are widely used in thermal interface materials.Despite...The increasing power density of chips poses a significant challenge in the form of material aging for aluminumfilled polydimethylsiloxane(Al/PDMS)composites,which are widely used in thermal interface materials.Despite the growing importance of this issue,the specific mechanisms behind the interfacial aging process remain elusive,hindering a comprehensive grasp of the aging dynamics in these composites.In our research,we have developed an in-situ Raman aging monitoring system that leverages the non-contact and high-resolution capabilities of Raman spectroscopy to study the interface aging process.Our findings indicate a notable decrease in the intensity of the Raman peak as further cross-linking of the molecules during aging,with the most pronounced decline occurring at the interface between aluminum and PDMS.This insight could potentially elucidate why the interface in composite materials is frequently the site of failure during aging.Our study offers a versatile methodology for investigating the interfacial aging of polymer composites,contributing to a broader understanding of the interface behavior in composite materials at the molecular level.展开更多
This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,t...This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.展开更多
The spatially-resolved laser-based high resolution angle resolved photoemission spectroscopy(ARPES)measurements have been performed on the optimally-doped HgBa_(2)Ca_(2)Cu_(3)O_(8+δ)(Hg1223)superconductor with a T_(c...The spatially-resolved laser-based high resolution angle resolved photoemission spectroscopy(ARPES)measurements have been performed on the optimally-doped HgBa_(2)Ca_(2)Cu_(3)O_(8+δ)(Hg1223)superconductor with a T_(c) of 133 K.Two distinct regions are identified on the cleaved surface:the single Fermi surface region where only one Fermi surface is observed,and the double Fermi surface region where two Fermi surface sheets are resolved coming from both the inner(IP)and outer(OP)CuO_(2) planes.The electronic structure and superconducting gap are measured on both of these two regions.In both cases,the observed electronic states are mainly concentrated near the nodal region.The momentum dependence of the superconducting gap deviates from the standard d-wave form.These results indicate that the surface electronic structure of Hg1223 behaves more like that of underdoped cuprates.展开更多
[Objectives]This study was conducted to achieve rapid and accurate detection of protein content in rice with a particle size of 1.0 mm.[Methods]A multi-model fusion strategy was proposed on the basis of Stacking ensem...[Objectives]This study was conducted to achieve rapid and accurate detection of protein content in rice with a particle size of 1.0 mm.[Methods]A multi-model fusion strategy was proposed on the basis of Stacking ensemble learning.A base learner pool was constructed,containing Partial Least Squares(PLS),Support Vector Machine(SVM),Deep Extreme Learning Machine(DELM),Random Forest(RF),Gradient Boosting Decision Tree(GBDT),and Multilayer Perceptron(MLP).PLS,DELM,and Linear Regression(LR)were used as meta-learner candidates.Employing integer coding technology,systematic dynamic combinations of base learners and meta-learners were generated,resulting in a total of 40 non-repetitive fusion models.The optimal combination was selected through a comprehensive evaluation based on multiple assessment indicators.[Results]The combination"PLS-DELM-MLP-LR"(code 1367)achieved coefficients of determination of 0.9732 and 0.9780 on the validation set and independent test set,respectively,with relative root mean square errors of 2.35%and 2.36%,and residual predictive deviations of 6.1075 and 6.7479,respectively.[Conclusions]The Stacking fusion model significantly enhances the predictive accuracy and robustness of spectral quantitative analysis,providing an efficient and feasible solution for modeling complex agricultural product spectral data.展开更多
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp...With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy.展开更多
The pseudo-two-dimensional(P2D)model plays an important role in exploring physicochemical mechanisms,predicting the state of health,and improving the fast charge capability for Li-ion batteries(LIBs).However,the fast ...The pseudo-two-dimensional(P2D)model plays an important role in exploring physicochemical mechanisms,predicting the state of health,and improving the fast charge capability for Li-ion batteries(LIBs).However,the fast charge leads to the lithium concentration gradient in the solid and electrolyte phases and the non-uniform electrochemical reaction at the solid/electrolyte interface.In order to decouple charge transfer reactions in LIBs under dynamic conditions,understanding the spatio-temporal resolution of the P2D model is urgently required.Till now,the study of this aspect is still insufficient.This work studies the spatio-temporal resolution for dynamic/static electrochemical impedance spectroscopy(DEIS/SEIS)on multiple scales.In detail,DEIS and SEIS with spatio-temporal resolutions are used to decouple charge transfer reactions in LIBs based on the numerical solution of the P2D model in the frequency domain.The calculated results indicate that decoupling solid diffusion requires a high spatial resolution along the r-direction in particles,decoupling electrolyte diffusion and interfacial transfer reaction requires a high spatial resolution along the x-direction,and decoupling charge transfer reactions in LIBs at an extremely low state of charge(SOC)requires an extremely high temporal resolution along the t-direction.Finally,the optimal range of spatio-temporal resolutions for DEIS/SEIS is derived,and the method to decouple charge transfer reactions with spatio-temporal resolutions is developed.展开更多
The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of ...The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of boreholes,extreme loss of circulation,and high-head inflow are also common in fractured strata,which often inhibit completion of probe holes and the reliability of coring,packer testing,and grouting tests.Casing,consequently,is a significant enabling technology to stabilize fractured intervals and has a hydraulic isolation under coupled mechanical and hydrogeological disturbances.The review is a synthesis of research and engineering experience on methods of casing to be used in horizontal drilling of fractured rock masses used in the exploration of water conveyance tunnels.The geological and working environment is initially outlined with a focus on fracture-adaptable instability processes and the special goings on of underground drilling,such as the restricted workspace,cuttings difficult to move,and fast movement of the competent and crushed regions.Types of casing systems are then listed,including both standard threaded steel strings and telescopic programs,and more specialized casing system types,including expandable casing,swellable sealing elements,and external casing packers.Special focus is made on the sealing of annulus in horizontal holes,wherein slurry loss,gravity segregation,and non-uniform borehole geometry usually worsen isolation.Lastly,the article suggests adaptive choice of strategy according to real-time drilling reaction,and research priorities,such as tunnel-specific performance measurements,coupled hydro-mechanical modelling,and field trials of sophisticated sealing material and data-driven choice making.展开更多
This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical ...This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(R_(D/G))and vitrinite reflectance(R_(o)).展开更多
Many spore-forming Bacillus species can cause serious human diseases,because of accidental Bacillusspore infection.Thus,developing an identification strategy with both high sensitivity and specificity is greatly in de...Many spore-forming Bacillus species can cause serious human diseases,because of accidental Bacillusspore infection.Thus,developing an identification strategy with both high sensitivity and specificity is greatly in demand.In this work,we proposed a novel approach named multi-head self-attention mechanism-guided neural network Raman platform to identify living Bacillus spores within a single-cell resolution.The multi-head self-attention mechanism-guided neural network Raman platform was created by combining single-cell Raman spectroscopy,convolutional neural network(CNN),and multi-head self-attention mechanism.To address the limited size of the original spectra dataset,Gaussian noise-based spectra augmentation was employed to increase the number of single-cell Raman spectra datasets for CNN training.Owing to the assistance of both spectra augmentation and multi-head self-attention mechanism,the obtained prediction accuracy of five Bacillus spore species was further improved from 92.29±0.82%to 99.43±0.15%.To figure out the spectra differences covered by the multi-head self-attention mechanism-guided CNN,the relative classification weight from typical Raman bands was visualized via multi-head self-attention mechanism curve.In the process of spectra augmentation from 0 to 1000,the distribution of relative classification weight varied from a discrete state to a more concentrated phase.More importantly,these highlighted four Raman bands(1017,1449,1576,and 1660 cm^(-1))were assigned large weights,showing that the spectra differences in the Raman bands produced the largest contribution to prediction accuracy.It can be foreseen that,our proposed sorting platform has great potential in accurately identifying Bacillus and its related genera species at a single-cell level.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12027809,12350007)National Key R&D Program of China(Nos.2022YFA1605100,2023YFA1606403,and 2023YFE0101600)+1 种基金New Cornerstone Science Foundation through the XPLORER PRIZEfunding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program under grant agreement No.679038.
文摘A RadioFrequency Quadrupole(RFQ)cooler-buncher system was developed and implemented in a collinear laser spectroscopy setup.This system converts a continuous ion beam into short bunches while enhancing the beam quality and reducing the energy spread.The functionality of the RFQ cooler buncher was verified through offline tests with stable rubidium and indium beams delivered from a surface ion source and a laser ablation ion source,respectively.Bunched ion beams with a full width at half maximum of approximately 2μs in the time-of-flight spectrum were successfully achieved with a transmission efficiency exceeding 60%.The implementation of the RFQ cooler-buncher system also significantly improved the overall transmission efficiency of the collinear laser spectroscopy setup.
基金Funded by the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2024QN05023)High Level Talent Research Launch Foundation of Inner Mongolia University(No.10000-22311201/008)。
文摘Electrochemical impedance spectroscopy(EIS)was used to examine the electrical properties of metakaolin(MK)cement-based materials at elevated temperatures.We utilized a new equivalent circuit to investigate the EIS results of cementitious materials blended with MK at these temperatures.A new evaluation method to high temperature damage is proposed.The findings show that both elevated temperatures and MK contents in cement mortar can impact the impedance spectra’s form properties.However,the residual compressive strength of the MK-blended cementitious material at elevated temperatures does not improve with the addition of MK.A quantitative relationship between the electrochemical parameters of the new equivalent circuit and the residual compressive strength is determined.The degree of high-temperature damage to cementitious materials can be evaluated based on these electrochemical parameters,providing a new approach for evaluating the high-temperature damage of MK-blend cementitious materials.
基金funded by the EU H2020 Marie Skłodowska-Curie Fellowship (1439425)the National Natural Science Foundation of China (No. 52171199 and 22479011)
文摘Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.
文摘The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility.
基金financially supported by the National Natural Science Foundation of China (22350410386,W2412116,22375200,U22A202175,21961142006)。
文摘Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm.
基金supported by the National Key R&D Program of China(No.2021YFA1601003)the financial support of the SSRF PhaseⅡproject.
文摘This paper describes the design and performance of the tender energy spectroscopy beamline(BL16U1),a phase Ⅱ beamline,at the Shanghai Synchrotron Radiation Facility.The beamline,based on an in-vacuum undulator source with 26 mm period,provides an operable energy range between 2.1 keV and 16 keV,covering the K-edges of P to Rb and L3-edges of Zr to Bi.The principal optical elements of the beamline are a toroidal mirror,a liquid nitrogen-cooled double-crystal monochromator,a high-harmonic-rejection mirror,and two pairs of Kirkpatrick–Baez(KB)mirrors.Three end-stations,including non-focusing,microprobe,and sub-microprobe types,are installed on the beamline.X-ray fluorescence(XRF)and X-ray absorption spectroscopy(XAS),including X-ray absorption near-edge structure(XANES)and extended X-ray absorption fine structure(EXAFS),are performed under vacuum or He atmosphere at the non-focusing end-station(with a beam spot size of∼670μm×710μm).Using two KB mirrors systems,micro-XRF(μXRF)mapping and micro-XANES(μXANES)studies can be performed with a spot size of approximately∼3.3μm×1.3μm at the microprobe end-station and with a smaller spot size of∼0.5μm×0.25μm at the sub-microprobe end-station.The non-focusing end-station was officially opened to users in January 2024.The microprobe and sub-microprobe end-stations will be opened to users in the near future.This paper presents the characteristics,short-term technical developments,and early experimental results of this new beamline.
基金supported by the Science and Technology Project of Qinghai Province(Grant No.2025-ZJ-T0)the National Key Research and Development Program of China(Grant No.2023YFE0109900)the Minor Planet Foundation of China.
文摘Optical monitoring of fireballs can provide reconstructions of luminous trajectories and the derivation of heliocentric orbits,whereas spectral observations are able to supply information from an entirely different perspective,with composition and material data.Observing and analyzing a fireball by using both methods enables a complete characterization of its meteorite properties.We simultaneously collected luminous and spectral observations of fireballs through observation networks established in eastern China and the Western Cape of South Africa.The optical observations utilized 180°×180°fisheye cameras,whereas spectral data were recorded by fixing gratings in front of each camera lens on the Allsky7 instrument so that both could monitor fireballs within an all-sky field of view.The spectra had an effective resolution of R=200.During the first year of operation,the network detected spectra from 150 fireballs,most of which recognized at least Mg I and Na I emission lines,and both the spectra and trajectory were recorded for some.Preliminary analysis of four bright fireballs indicated they could be categorized as asteroidal orbits or Halley-type cometary orbits,with spectra classified as normal,Fe-rich,iron,and Na-poor,respectively.One Halley-type fireball belonged to the Perseid meteor shower.For the two fireballs on asteroid-like orbits,orbital comparisons with known near-Earth asteroids were performed using multiple D-criteria(orbital similarity functions).Under the D_(N)criterion,SAFB20250713(iron type)showed a loose possible match with 2021 BD,whereas JsFB20250110(Fe-rich type)exhibited a closer potential similarity with 2017 BK(D_(N)=0.03).Overall,the orbital comparison indicated possible associations but no definitive parent bodies,whereas the spectral characteristics were broadly consistent with the asteroid-like or comet-like nature implied by their orbital classes.
基金Supported by Zhoukou Key Science and Technology Research Project(20200816).
文摘With the expansion of peanut planting area year by year,film mulching cultivation has become increasingly important in peanut production due to its unique advantages in enhancing both yield per unit area and overall economic benefits.Based on the varietal characteristics of‘Zhouhua 5’and addressing practical issues in peanut production,this paper summarized key techniques for high-yield and high-efficiency film mulching cultivation of this variety.These techniques cover all critical stages,including land preparation and fertilization,seed preparation,sowing methods,field management,and timely harvesting,providing technical guidance for varietal promotion and peanut production.
基金supported by Healthy China initiative of Traditional Chinese Medicine(No.889042).
文摘Currently,the number of patients with myopia is increasing rapidly across the globe.Traditional Chinese medicine(TCM),with its long history and rich experience,has shown promise in effectively managing and treating this condition.Nevertheless,considering the vast amount of research that is currently being conducted,focusing on the utilization of TCM in the management of myopia,there is an urgent requirement for a thorough and comprehensive review.The review would serve to clarify the practical applications of TCM within this specific field,and it would also aim to elucidate the underlying mechanisms that are at play,providing a deeper understanding of how TCM principles can be effectively integrated into modern medical practices.Here,some modern medical pathogenesis of myopia and appropriate TCM techniques studies are summarized in the prevention and treatment of myopia.Further,we discussed the potential mechanisms and the future research directions of TCM against myopia.Identifying these mechanisms is crucial for understanding how TCM can be effectively utilized in this context.The combination of various TCM methods or the combination of traditional Chinese and Western medicine is of great significance for the prevention and control of myopia in the future.
基金the Deanship of Graduate Studies and Scientific Research at University of Bisha for supporting this work through the Fast-Track Research Support Programthe Deanship of Scientific Research at Northern Border University,Arar,KSA for funding this research work through the project number“NBU-FFR-2025-2903-09”.
文摘Network-on-Chip(NoC)systems are progressively deployed in connecting massively parallel megacore systems in the new computing architecture.As a result,application mapping has become an important aspect of performance and scalability,as current trends require the distribution of computation across network nodes/points.In this paper,we survey a large number of mapping and scheduling techniques designed for NoC architectures.This time,we concentrated on 3D systems.We take a systematic literature review approach to analyze existing methods across static,dynamic,hybrid,and machine-learning-based approaches,alongside preliminary AI-based dynamic models in recent works.We classify them into several main aspects covering power-aware mapping,fault tolerance,load-balancing,and adaptive for dynamic workloads.Also,we assess the efficacy of each method against performance parameters,such as latency,throughput,response time,and error rate.Key challenges,including energy efficiency,real-time adaptability,and reinforcement learning integration,are highlighted as well.To the best of our knowledge,this is one of the recent reviews that identifies both traditional and AI-based algorithms for mapping over a modern NoC,and opens research challenges.Finally,we provide directions for future work toward improved adaptability and scalability via lightweight learned models and hierarchical mapping frameworks.
基金financial supports from the National Natural Science Foundation of China(Grant No.62335006,62275065,624B2050,62022032,and 62405078)Open Subject of Hebei Key Laboratory of Advanced Laser Technology and Equipment(HBKL-ALTE2025001)+2 种基金Heilongjiang Postdoctoral Fund(Grant No.LBH-Z23144 and LBH-Z24155)Natural Science Foundation of Heilongjiang Province(Grant No.LH2024F031)China Postdoctoral Science Foundation(Grant No.2024M764172).
文摘In this paper,a fast step heterodyne light-induced thermoelastic spectroscopy(SH-LITES)sensor using a high-frequency quartz tuning fork(QTF)with resonant frequency of~100 kHz is reported for the first time.The theoretical principle of heterodyne LITES(H-LITES)signal generation is analyzed firstly,and an acetylene(C_(2)H_(2))H-LITES sensor is established to verify its performance.Experimental comparisons between the high-frequency QTF and a standard commercial QTF with resonant frequency of~32.768 kHz reveal that the high-frequency QTF exhibits a tenfold faster response time.Specifically,the H-LITES sensor with this QTF achieves a 33 ms measurement cycle,90%shorter than commercial counterparts.Furthermore,The SH-LITES technique is proposed to further shorten the scanning time to 15 ms,which achieves the shortest LITES measurement time known to date.To demonstrate its advantages in dynamic gas detection,an H_(2)O-LITES system integrating both QTF types is constructed for real-time monitoring of H_(2)O concentration during different respiration patterns.Comparative measurements show that the SH-LITES more accurately captures dynamic H_(2)O concentration fluctuations during respiration,outperforming the commercial QTF-based H-LITES sensor in rapid response scenarios.
基金supported by the National Natural Science Foundation of China(No.52303092)Talent Recruitment Project of Guangdong Province(No.2023QN10X078)+2 种基金Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(No.YPML-2023050278)National Key R&D Project from Ministry of Science and Technology of China(No.2022YFA1203100)Shenzhen Science and Technology Research Funding(No.JCYJ20200109114401708)。
文摘The increasing power density of chips poses a significant challenge in the form of material aging for aluminumfilled polydimethylsiloxane(Al/PDMS)composites,which are widely used in thermal interface materials.Despite the growing importance of this issue,the specific mechanisms behind the interfacial aging process remain elusive,hindering a comprehensive grasp of the aging dynamics in these composites.In our research,we have developed an in-situ Raman aging monitoring system that leverages the non-contact and high-resolution capabilities of Raman spectroscopy to study the interface aging process.Our findings indicate a notable decrease in the intensity of the Raman peak as further cross-linking of the molecules during aging,with the most pronounced decline occurring at the interface between aluminum and PDMS.This insight could potentially elucidate why the interface in composite materials is frequently the site of failure during aging.Our study offers a versatile methodology for investigating the interfacial aging of polymer composites,contributing to a broader understanding of the interface behavior in composite materials at the molecular level.
基金the Italian Ministry of Universities and Research for funding his PhD scholarship(37th Cycle Ph D Programmes supported by ESF REACT-EU funds,National Operational Programme on Research and Innovation)CSGI(Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase-Center for Colloid and Surface Science),Florence(Italy)for financial support.
文摘This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFA1401800,2022YFA1604200,2022YFA1403900,2023YFA1406002,2024YFA1408301 and 2024YFA1408100)the National Natural Science Foun-dation of China(Grant Nos.12488201,12374066,12374154,12494593)+2 种基金Quantum Science and Technology-National Science and Technology Major Project(Grant No.2021ZD0301800)CAS Superconducting Research Project(Grant No.SCZX-0101)the Synergetic Extreme Condition User Facility(SECUF).
文摘The spatially-resolved laser-based high resolution angle resolved photoemission spectroscopy(ARPES)measurements have been performed on the optimally-doped HgBa_(2)Ca_(2)Cu_(3)O_(8+δ)(Hg1223)superconductor with a T_(c) of 133 K.Two distinct regions are identified on the cleaved surface:the single Fermi surface region where only one Fermi surface is observed,and the double Fermi surface region where two Fermi surface sheets are resolved coming from both the inner(IP)and outer(OP)CuO_(2) planes.The electronic structure and superconducting gap are measured on both of these two regions.In both cases,the observed electronic states are mainly concentrated near the nodal region.The momentum dependence of the superconducting gap deviates from the standard d-wave form.These results indicate that the surface electronic structure of Hg1223 behaves more like that of underdoped cuprates.
文摘[Objectives]This study was conducted to achieve rapid and accurate detection of protein content in rice with a particle size of 1.0 mm.[Methods]A multi-model fusion strategy was proposed on the basis of Stacking ensemble learning.A base learner pool was constructed,containing Partial Least Squares(PLS),Support Vector Machine(SVM),Deep Extreme Learning Machine(DELM),Random Forest(RF),Gradient Boosting Decision Tree(GBDT),and Multilayer Perceptron(MLP).PLS,DELM,and Linear Regression(LR)were used as meta-learner candidates.Employing integer coding technology,systematic dynamic combinations of base learners and meta-learners were generated,resulting in a total of 40 non-repetitive fusion models.The optimal combination was selected through a comprehensive evaluation based on multiple assessment indicators.[Results]The combination"PLS-DELM-MLP-LR"(code 1367)achieved coefficients of determination of 0.9732 and 0.9780 on the validation set and independent test set,respectively,with relative root mean square errors of 2.35%and 2.36%,and residual predictive deviations of 6.1075 and 6.7479,respectively.[Conclusions]The Stacking fusion model significantly enhances the predictive accuracy and robustness of spectral quantitative analysis,providing an efficient and feasible solution for modeling complex agricultural product spectral data.
基金supported by the Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(No.RS-2023-00235509Development of security monitoring technology based network behavior against encrypted cyber threats in ICT convergence environment).
文摘With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy.
基金supported by the National Natural Science Foundation of China(Nos.22479092 and 22078190)。
文摘The pseudo-two-dimensional(P2D)model plays an important role in exploring physicochemical mechanisms,predicting the state of health,and improving the fast charge capability for Li-ion batteries(LIBs).However,the fast charge leads to the lithium concentration gradient in the solid and electrolyte phases and the non-uniform electrochemical reaction at the solid/electrolyte interface.In order to decouple charge transfer reactions in LIBs under dynamic conditions,understanding the spatio-temporal resolution of the P2D model is urgently required.Till now,the study of this aspect is still insufficient.This work studies the spatio-temporal resolution for dynamic/static electrochemical impedance spectroscopy(DEIS/SEIS)on multiple scales.In detail,DEIS and SEIS with spatio-temporal resolutions are used to decouple charge transfer reactions in LIBs based on the numerical solution of the P2D model in the frequency domain.The calculated results indicate that decoupling solid diffusion requires a high spatial resolution along the r-direction in particles,decoupling electrolyte diffusion and interfacial transfer reaction requires a high spatial resolution along the x-direction,and decoupling charge transfer reactions in LIBs at an extremely low state of charge(SOC)requires an extremely high temporal resolution along the t-direction.Finally,the optimal range of spatio-temporal resolutions for DEIS/SEIS is derived,and the method to decouple charge transfer reactions with spatio-temporal resolutions is developed.
文摘The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of boreholes,extreme loss of circulation,and high-head inflow are also common in fractured strata,which often inhibit completion of probe holes and the reliability of coring,packer testing,and grouting tests.Casing,consequently,is a significant enabling technology to stabilize fractured intervals and has a hydraulic isolation under coupled mechanical and hydrogeological disturbances.The review is a synthesis of research and engineering experience on methods of casing to be used in horizontal drilling of fractured rock masses used in the exploration of water conveyance tunnels.The geological and working environment is initially outlined with a focus on fracture-adaptable instability processes and the special goings on of underground drilling,such as the restricted workspace,cuttings difficult to move,and fast movement of the competent and crushed regions.Types of casing systems are then listed,including both standard threaded steel strings and telescopic programs,and more specialized casing system types,including expandable casing,swellable sealing elements,and external casing packers.Special focus is made on the sealing of annulus in horizontal holes,wherein slurry loss,gravity segregation,and non-uniform borehole geometry usually worsen isolation.Lastly,the article suggests adaptive choice of strategy according to real-time drilling reaction,and research priorities,such as tunnel-specific performance measurements,coupled hydro-mechanical modelling,and field trials of sophisticated sealing material and data-driven choice making.
基金supported by the National Natural Science Foundation of China(42362022)the Open Fund of the Shaanxi Key Laboratory of Petroleum Accumulation Geology(PAG-202406)the Open Fund of the Mine Geology and Environment Academician and Expert Workstation(2024OITYSZJGZZ-005)。
文摘This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(R_(D/G))and vitrinite reflectance(R_(o)).
基金partially supported by the National Natural Science Foundation of China(62075137)the Guangdong Basic and Applied Basic Research Foundation(2023A1515140161)+3 种基金the Guangxi Natural Science Foundation of China(2021JJB 110003)the Dongguan Science and Technology of Social Development Program(20231800936312)the high-level talent program of Dongguan University of Technology(No.221110080)the Sanming Project of Medicine in Shenzhen(No.SZSM202103014).
文摘Many spore-forming Bacillus species can cause serious human diseases,because of accidental Bacillusspore infection.Thus,developing an identification strategy with both high sensitivity and specificity is greatly in demand.In this work,we proposed a novel approach named multi-head self-attention mechanism-guided neural network Raman platform to identify living Bacillus spores within a single-cell resolution.The multi-head self-attention mechanism-guided neural network Raman platform was created by combining single-cell Raman spectroscopy,convolutional neural network(CNN),and multi-head self-attention mechanism.To address the limited size of the original spectra dataset,Gaussian noise-based spectra augmentation was employed to increase the number of single-cell Raman spectra datasets for CNN training.Owing to the assistance of both spectra augmentation and multi-head self-attention mechanism,the obtained prediction accuracy of five Bacillus spore species was further improved from 92.29±0.82%to 99.43±0.15%.To figure out the spectra differences covered by the multi-head self-attention mechanism-guided CNN,the relative classification weight from typical Raman bands was visualized via multi-head self-attention mechanism curve.In the process of spectra augmentation from 0 to 1000,the distribution of relative classification weight varied from a discrete state to a more concentrated phase.More importantly,these highlighted four Raman bands(1017,1449,1576,and 1660 cm^(-1))were assigned large weights,showing that the spectra differences in the Raman bands produced the largest contribution to prediction accuracy.It can be foreseen that,our proposed sorting platform has great potential in accurately identifying Bacillus and its related genera species at a single-cell level.
