Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused ...Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused by mystery reason.To cure phlegm and blood stasis simultaneously,the therapy promotes the notion of“resolving phlegm and stimulating the circulation of blood,liberate brain orifices,”and treatments with the addition and removal of“Naotaitong Decoction,”which has an amazing clinical curative effect.This paper examines Professor Jun Li’s theoretical foundations and ideas from the syndrome differentiation and treatment of phlegm and blood stasis,systematically examines the curative effect and mechanism of Naotaitong Decoction in the treatment of vascular dementia,and examines the prescription and medication of typical cases for readers,in the hopes of providing guidance to clinical diagnosis and treatment of this disease.展开更多
Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformat...Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformation,while the mechanism has not been fully understood at the mesoscale.In this work,a model coupling dendrite growth,thermal-solutal-fluid flow,thermal stress and flow-induced dendrite deformation via cellular automaton-finite volume method and finite element method is developed to study the formation of LAGBs in single crystal superalloys.Results reveal that the bending of dendrites is primarily attributed to the thermal-solutal convection-induced dendrite deformation.The mechanical stress of dendrite deformation develops and stabilises as solidification proceeds.As the width of the mushy zone gets stable,stresses are built up and then dendritic elastoplastic bending occurs at some thin primary dendrites with the wider inter-dendritic space.There are three characteristic zones of stress distribution along the solidification direction:(i)no stress concentration in the fully solidified regions;(ii)stress developing in the primary dendrite bridging region,and(iii)stress decrease in the inter-dendritic uncontacted zone.The stresses reach maximum near the initial dendrite bridging position.The lower temperature gradients,the finer primary dendritic trunks and sudden reductions in local dendritic trunk radius jointly promote the elastoplastic deformation of the dendrites.Corresponding measures are suggested to reduce LAGBs.展开更多
In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the ...In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the research samples,this paper conducts an empirical test on the impact of the digital transformation of logistics enterprises on their green in-novation.Specifically,enterprise digital transformation indicators are constructed through the text analysis method,and the fixed-effects model is applied for analysis.The results indicate that the digital transformation of logistics enterprises has a significant promoting effect on their green innovation;the promoting effect of the digital transformation of logistics enterprises on green innovation is primarily achieved by easing corporate financing constraints and reducing corporate en-vironmental uncertainty;and the impact of digital transformation on green innovation is geographically heterogeneous.展开更多
The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(...The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(N)use efficiency and reduce environmental impacts is still unclear.Here,we examined the data from 502 valid questionnaires collected from WFFPs in the major grain-producing area,the Huang-Huai-Hai Region(HHHR)in China,with 429 samples for wheat,328 for maize,and 122 for rice.We identified gaps in N use efficiency(NUE)and N losses from the production of the three crops between the sampled WFFPs and counties based on the statistical data.The results showed that compared to the county-level(wheat,39.1%;maize,33.8%;rice,35.1%),the NUEs for wheat(55.2%),maize(52.1%),and rice(50.2%)in the WFFPs were significantly improved(P<0.05).In addition,the intensities of ammonia(NH3)volatilization(9.9-12.2 kg N ha–1),N leaching(6.5-16.9 kg N ha–1),and nitrous oxide(N2O)emissions(1.2-1.6 kg N ha–1)from crop production in the sampled WFFPs were significantly lower than the county averages(P<0.05).Simulations showed that if the N rates are reduced by 10.0,15.0,and 20.0%for the counties,the NUEs of wheat,maize,and rice in the HHHR will increase by 2.9-6.3,2.4-5.2,and 2.6-5.7%,respectively.If the N rate is reduced to the WFFP level in each county,the NUEs of the three crops will increase by 12.9-19.5%,and the N leaching,NH3,and N2O emissions will be reduced by 48.9-56.2,37.4-42.9,and 46.0-66.5%,respectively.Our findings highlight that efficient N management practices in sustainable intensive farmland have considerable potential for reducing environmental impacts.展开更多
H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an i...H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an innovative method for storing and releasing H_(2)O_(2)using hydrogels.Commercial hydrogels(sodium polyacrylate)can undergo swelling and absorb H_(2)O_(2)in aqueous solutions,and the swollen hydrogel can continuously release H_(2)O_(2)under osmotic pressure.And the characteristics of osmotic pressure drive ensure the recyclability of hydrogel for H_(2)O_(2)storage.Experimental results demonstrate that H_(2)O_(2)can stably exist within the hydrogel for an extended period,and this strategy helps to avoid explosion the risk and potential environmental hazards during the transportation of H_(2)O_(2).Finally,experiments confirm that the hydrogel controlled sustained release of H_(2)O_(2)is effective in both Fenton reactions and the process of bacterial inactivation.This work introduces new ideas for the storage of H_(2)O_(2),and the sustained release of H_(2)O_(2)may have significant implications in the fields of healthcare,environmental science,catalysis,and beyond.展开更多
Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has bee...Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has been advocated for decentralized data management in a tamper-resistance,traceable,and transparent manner.However,a major issue that hinders the integration of blockchain and IoT lies in that,it is rather challenging for resource-constrained IoT devices to perform computation-intensive blockchain consensuses such as Proof-of-Work(PoW).Furthermore,the incentive mechanism of PoW pushes lightweight IoT nodes to aggregate their computing power to increase the possibility of successful block generation.Nevertheless,this eventually leads to the formation of computing power alliances,and significantly compromises the decentralization and security of BlockChain-aided IoT(BC-IoT)networks.To cope with these issues,we propose a lightweight consensus protocol for BC-IoT,called Proof-of-Trusted-Work(PoTW).The goal of the proposed consensus is to disincentivize the centralization of computing power and encourage the independent participation of lightweight IoT nodes in blockchain consensus.First,we put forth an on-chain reputation evaluation rule and a reputation chain for PoTW to enable the verifiability and traceability of nodes’reputations based on their contributions of computing power to the blockchain consensus,and we incorporate the multi-level block generation difficulty as a rewards for nodes to accumulate reputations.Second,we model the block generation process of PoTW and analyze the block throughput using the continuous time Markov chain.Additionally,we define and optimize the relative throughput gain to quantify and maximize the capability of PoTW that suppresses the computing power centralization(i.e.,centralization suppression).Furthermore,we investigate the impact of the computing power of the computing power alliance and the levels of block generation difficulty on the centralization suppression capability of PoTW.Finally,simulation results demonstrate the consistency of the analytical results in terms of block throughput.In particular,the results show that PoTW effectively reduces the block generation proportion of the computing power alliance compared with PoW,while simultaneously improving that of individual lightweight nodes.This indicates that PoTW is capable of suppressing the centralization of computing power to a certain degree.Moreover,as the levels of block generation difficulty in PoTW increase,its centralization suppression capability strengthens.展开更多
The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In...The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In this paper,we introduce a transient wellbore multiphase flow model specifically developed to simulate gas kick in deepwater dual-gradient drilling,incorporating a downhole separator.The model accounts for the variable mass flow within the annulus and heat exchange between the annular fluid and the formation.Using this model,we analyzed the multiphase flow and thermodynamic behavior during the gas kick.Simulation results reveal a progressive increase in bottom-hole temperature,underscoring its potential as a key indicator for gas kick early detection.Additionally,variable gradient parameters affect not only the annular equivalent circulating density(ECD)profile but also the evolution of the gas kick.The inclusion of a downhole separator alters the annular ECD profile,creating a“broken line”shape,which enhances adaptability to the multi-pressure systems typically encountered in deepwater forma-tion.By adjusting factors such as hollow sphere concentration,separator position,and separation effi-ciency,the annular ECD profile can be effectively customized.This study provides important theoretical insights and practical applications for utilizing dual-gradient drilling technology to address challenges in deepwater formation drilling.展开更多
This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of e...This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of existing methods,a dynamic model is developed for both free and forced vibration scenarios.These models incorporate the virtual spring technology to accurately simulate a wide range of boundary conditions.Using the first-order shear deformation theory in conjunction with the Jacobi orthogonal polynomials,an energy expression is formulated,and the natural frequencies and mode shapes are determined via the Ritz method.Based on the Newmark-βmethod,the pulse response amplitudes and attenuation characteristics under various transient excitation loads are analyzed and evaluated.The accuracy of the theoretical model and the vibration suppression capability of the damping gel are experimentally validated.Furthermore,the effects of key structural parameters on the natural frequency and vibration response are systematically examined.展开更多
Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencin...Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencing the SX structure.Casting deformation is simulated in most of the previous studies,whereas the direct simulation of dendritic thermomechanical deformation has been largely ignored,resulting in a lack of comprehensive understanding of this process.In this study,we systematically investigate dendritic thermomechanical deformation with a model coupled with dendrite growth,fluid flow,and thermomechanical deformation behavior.Results reveal that the dendritic thermomechanical deformation-induced dendrite bending is not randomly distributed but is mainly concentrated on the casting surface.The dendritic thermal stress increases as dendrite grows and accumulates after dendrite bridging.Transverse thermal contraction mainly occurs at the edge of casting in the corner,and axial thermal contraction is larger than transverse contraction.The high-stress region of the primary dendrite trunk is mainly distributed below the dendrite bridging near the solidified part,and the stress along the transverse direction reaches its maximum value on the casting surface.Stress concentrated on the casting surface is mainly attributed to variations in transverse temperature gradients caused by heat dissipation on the lateral mold wall,and inconsistent constraints in the lateral mold walls.展开更多
BACKGROUND Gastrointestinal schwannomas(GIS)are rare neurogenic tumors arising from Schwann cells in the gastrointestinal tract.Studies on GIS are limited to small case reports or focus on specific tumor sites,undersc...BACKGROUND Gastrointestinal schwannomas(GIS)are rare neurogenic tumors arising from Schwann cells in the gastrointestinal tract.Studies on GIS are limited to small case reports or focus on specific tumor sites,underscoring the diagnostic and thera-peutic challenges they pose.AIM To comprehensively examine the clinical features,pathological characteristics,treatment outcomes,associated comorbidities,and prognosis of GIS.METHODS The study population included patients diagnosed with GIS at the First Affiliated Hospital,Zhejiang University School of Medicine,between June 2007 and April 2024.Data were retrospectively collected and analyzed from medical records,including demographic characteristics,endoscopic and imaging findings,treatment modalities,pathological evaluations,and follow-up information.RESULTS In total,229 patients with GIS were included,with a mean age of 56.00 years and a male-to-female ratio of 1:1.83.The mean tumor size was 2.75 cm,and most(76.9%)were located in the stomach.Additionally,6.6%of the patients had other malig-nant tumors.Preoperative imaging and endoscopy frequently misdiagnosed GIS as gastrointestinal stromal tumors.However,accurate preoperative diagnosis was achieved using endoscopic ultrasound-guided fine-needle aspiration combined with immunohistochemical analysis,in which S100 and SOX-10 markers were mostly positive.Smaller tumors were typically managed with endoscopic resection,while larger lesions were treated with surgical resection.Follow-up results showed that most patients experienced favorable outcomes.CONCLUSION Preoperative diagnosis of GIS via clinical characteristics,endoscopy,and imaging examinations remains challenging but crucial.Endoscopic therapy provides a minimally invasive and effective option for patients.展开更多
The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within ...The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within the 3 mm band using the FTS wide-sideband mode of the IRAM 30 m telescope toward 20 gas-infalling sources.Using XCLASS,we identify the emission lines of up to 22 molecular species(including a few isotopologues)and on hydrogen radio recombination line in these sources.H^(13)CO^(+),HCO^(+),HCN,HNC,c-C_(3)H_(2),and CCH lines are detected in 15 sources.We estimate the rotation temperatures and column densities of these molecular species using the LTE radiative transfer model,and compare the molecular abundances of these sources with those from nine high mass star-forming regions reported in previous studies and with those from the chemical model.Our results sugges that G012.79-0.20,G012.87-0.22 clump A and B,and G012.96-0.23 clump A may be in the high-mass protostella object stage,while sources with fewer detected species may be in the earlier evolutionary stage.Additionally,th CCH and c-C_(3)H_(2)column densities in our sources reveal a linear correlation,with a ratio of N(CCH)/N(c-C_(3)H_(2)=89.2±5.6),which is higher than the ratios reported in the literature.When considering only sources with lowe column densities,this ratio decreases to 29.0±6.1,consistent with those of diffuse clouds.Furthermore,comparison between the N(CCH)/N(c-C_(3)H_(2))ratio and the sources’physical parameters reveals a correlation,with sources exhibiting higher ratios tending to have higher kinetic temperatures and H2column densities.展开更多
Background:Bacterial pneumonia continues to be a significant global health concern,particularly among high-risk groups,necessitating the development of precise and early diagnostic biomarkers.While the efficacy of pro...Background:Bacterial pneumonia continues to be a significant global health concern,particularly among high-risk groups,necessitating the development of precise and early diagnostic biomarkers.While the efficacy of procalcitonin(PCT)and C-reactive protein(CRP)as inflammatory markers is widely recognized,their relative diagnostic performance across different age groups remains debate.This meta-analysis was designed to assess the diagnostic accuracy of PCT and CRP in bacterial pneumonia.Methods:In this meta-analysis adhering to PRISMA guidelines,we searched PubMed,Web of Science,and the Cochrane Library for relevant diagnostic accuracy studies.From 19 included studies(n=2,603),data were extracted to construct tables.Study quality was assessed with the QUADAS-2 tool.The bivariate random-effects model was employed to derive pooled sensitivity,specificity,positive and negative likelihood ratios,and summary AUCs.To explore the substantial heterogeneity(I^(2)>80%),we performed pre-specified subgroup analyses based on age demographics.Results:Our findings indicate superior diagnostic performance for PCT,evidenced by a pooled sensitivity of 0.8841 and specificity of 0.8499,relative to CRP’s sensitivity of 0.8371 and specificity of 0.7185.The area under the ROC curve(AUC)for PCT was 0.992,a value significantly higher than that of CRP(0.987).Intriguingly,subgroup analyses revealed age-dependent variations:CRP demonstrated enhanced diagnostic utility in minors,while PCT proved substantially more effective in non-elderly adults.Conclusion:These results reinforce the clinical relevance of PCT as a more dependable biomarker for bacterial pneumonia,particularly in informing antibiotic treatment and mitigating misuse.This study uniquely includes age-stratified analyses based on predefined groups(minors and non-elderly adults),providing refined insights for individualized diagnostic approaches.We propose further multicenter research endeavors to confirm threshold optimization and explore combined biomarker strategies.展开更多
The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LW...The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LWD).Several numerical methods,including the method of moments(MoM),the electric field integral equation(EFIE)method,and the finite-element(FE)method have been developed for the simulation of EM telemetry systems.The computational process of these methods is complicated and time-consuming.To solve this problem,we introduce an axisymmetric semi-analytical FE method(SAFEM)in the cylindrical coordinate system with the virtual layering technique for rapid simulation of EM telemetry in a layered earth.The proposed method divides the computational domain into a series of homogeneous layers.For each layer,only its cross-section is discretized,and a high-precision integration method based on Riccati equations is employed for the calculation of longitudinally homogeneous sections.The block-tridiagonal structure of the global coefficient matrix enables the use of the block Thomas algorithm,facilitating the efficient simulation of EM telemetry problems in layered media.After the theoretical development,we validate the accuracy and efficiency of our algorithm through a series of numerical experiments and comparisons with the Multiphysics modeling software COMSOL.We also discussed the impact of system parameters on EM telemetry signal and demonstrated the applicability of our method by testing it on a field dataset acquired from Dezhou,Shandong Province,China.展开更多
The rapid-cycling synchrotron(RCS)is a crucial device for proton beam acceleration at the China Spallation Neutron Source,operating at a repetition frequency of 25 Hz.The beam power was increased from 100 kW to 140 kW...The rapid-cycling synchrotron(RCS)is a crucial device for proton beam acceleration at the China Spallation Neutron Source,operating at a repetition frequency of 25 Hz.The beam power was increased from 100 kW to 140 kW.This increase makes the on-orbit beam more sensitive to disturbances in various parts of the accelerator,including the RCS magnet power supply system.This paper presents a method for reducing the high-order harmonic current error in resonant power supplies for dipole magnets and examines its impact on the horizontal orbit offset of the beam.It adopts a control scheme that combines high-order harmonic current compensation with PI double-loop control of the resonant power supply.By utilizing the existing digital controller hardware in the RCS power supply system,this study demonstrates how to achieve precise control of the 50 Hz harmonic current output in a cost-effective manner.Ultimately,it enhances performance by reducing the current error by up to 50%and provides methodological support for future upgrades to the power supply system.Such improvements enhance the stability of the RCS,reducing the beam horizontal orbit deviation by at least 19.8%.展开更多
Throughout the composite structure’s lifespan,it is subject to a range of environmental factors,including loads,vibrations,and conditions involving heat and humidity.These factors have the potential to compromise the...Throughout the composite structure’s lifespan,it is subject to a range of environmental factors,including loads,vibrations,and conditions involving heat and humidity.These factors have the potential to compromise the integrity of the structure.The estimation of the fatigue life of composite materials is imperative for ensuring the structural integrity of these materials.In this study,a methodology is proposed for predicting the fatigue life of composites that integrates ultrasonic guided waves and machine learning modeling.The method first screens the ultrasonic guided wave signal features that are significantly affected by fatigue damage.Subsequently,a covariance analysis is conducted to reduce the redundancy of the feature matrix.Furthermore,one-hot encoding is employed to incorporate boundary conditions as features,and the resulting data undergoes preprocessing to form a sample library.A composite fatigue life prediction model has been developed,employing the aforementioned sample library as the input source and utilizing remaining life as the output metric.The model synthesizes the strengths of convolutional neural networks(CNNs)and bidirectional long short-term memory networks(BiLSTMs)while leveraging Bayesian optimization(BO)to enhance the optimization of hyperparameters.The experimental results demonstrate that the proposed BO-CNN-BiLSTM model exhibits superior performance in terms of prediction accuracy and reliability in the damage regression task when compared to both the BiLSTM and CNN-BiLSTM models.展开更多
Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for ...Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.展开更多
Vegetables are essential and important foods in people s daily production,which are closely related to human health.Focusing on the present situation of vegetable nutrition and safety quality detection from detection ...Vegetables are essential and important foods in people s daily production,which are closely related to human health.Focusing on the present situation of vegetable nutrition and safety quality detection from detection indexes and detection methods,this paper discussed the selection of detection indexes and detection methods for vegetable nutrition and safety quality,and put forward the main research direction of vegetable nutrition and safety quality detection in the future,providing guidance and reference for improving vegetable nutrition and safety quality evaluation.展开更多
Formation pore pressure is the foundation of well plan,and it is related to the safety and efficiency of drilling operations in oil and gas development.However,the traditional method for predicting formation pore pres...Formation pore pressure is the foundation of well plan,and it is related to the safety and efficiency of drilling operations in oil and gas development.However,the traditional method for predicting formation pore pressure involves applying post-drilling measurement data from nearby wells to the target well,which may not accurately reflect the formation pore pressure of the target well.In this paper,a novel method for predicting formation pore pressure ahead of the drill bit by embedding petrophysical theory into machine learning based on seismic and logging-while-drilling(LWD)data was proposed.Gated recurrent unit(GRU)and long short-term memory(LSTM)models were developed and validated using data from three wells in the Bohai Oilfield,and the Shapley additive explanations(SHAP)were utilized to visualize and interpret the models proposed in this study,thereby providing valuable insights into the relative importance and impact of input features.The results show that among the eight models trained in this study,almost all model prediction errors converge to 0.05 g/cm^(3),with the largest root mean square error(RMSE)being 0.03072 and the smallest RMSE being 0.008964.Moreover,continuously updating the model with the increasing training data during drilling operations can further improve accuracy.Compared to other approaches,this study accurately and precisely depicts formation pore pressure,while SHAP analysis guides effective model refinement and feature engineering strategies.This work underscores the potential of integrating advanced machine learning techniques with domain-specific knowledge to enhance predictive accuracy for petroleum engineering applications.展开更多
Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopoly...Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopolysulfides incorporating N-heterocycles unveils promising cathode materials with stable cycling performance.Herein,the integration of organosulfides salt as cathodes with solid electrolytes,exemplified by sodium allyl(methyl)carbamodithioate and sodium diethylcarbamodithioate with a polymer solid electrolyte of polyethylene oxide and LiTFSI,addresses the poor electrochemical stability of organic electrodes.Comparative analysis highlights sodium allyl(methyl)carbamodithioate's superior electrochemical performance and stability compared with sodium diethylcarbamodithioate,emphasizing the efficacy of periphery aliphatic modification in enhancing electrode capacity,rate performance,and electrochemical stability for organosulfide materials within all-solid-state lithium organic batteries.We also explore the origin of periphery aliphatic modification in these enhancing electrochemical performances by kinetic analysis and thermodynamic analysis.Furthermore,employing density functional theory calculations and ex situ FTIR experiments elucidates the critical role of the N-C=S structure in the energy storage mechanism.This research advances organic cathode design within organosulfide materials,unlocking the potential of allsolid-state lithium organic batteries with enhanced cyclability,propelling the development of next-generation energy storage systems.展开更多
Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory...Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory electrochemical performance.In this study,CoF_(2)was combined with carbonaceous materials to obtain graphitic carbon-encapsulated CoF_(2)nanoparticles uniformly embedded in an interconnected N-doped carbon matrix(CoF_(2)@NC),significantly boosting the inert kinetics and electronic conductivity.The CoF_(2)@NC nanocomposites exhibited a notable reversible capacity of 352.0 mAh·g^(-1)at 0.2 A·g^(-1).Notably,it maintained superior long-term cycling stability even at a high current density of 2 A·g^(-1),with a capacity of 235.5 mAh·g^(-1)after 1200 cycles,evidently exceeding that of commercially available CoF_(2)electrodes.Kinetic analysis indicated that the enhanced electrochemical performance originated from the increased contribution of capacitive effects.Furthermore,in-situ electrochemical impedance spectroscopy(EIS)results verify that the improved cycling performance is associated with the enhanced interfacial stability of CoF_(2)@NC.This research not only proposes a solution for the challenges of conversion cathodes in lithium-ion batteries,but also offers novel synthesis strategies for designing high-energy metal fluoride materials.展开更多
基金Shaanxi excellent talents training project of traditional Chinese medicine(Shaanxi Traditional Chinese Medicine Letter[2020]112)Project of Shaanxi Administration of traditional Chinese medicine(No.2021-ZZ-LC016).
文摘Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused by mystery reason.To cure phlegm and blood stasis simultaneously,the therapy promotes the notion of“resolving phlegm and stimulating the circulation of blood,liberate brain orifices,”and treatments with the addition and removal of“Naotaitong Decoction,”which has an amazing clinical curative effect.This paper examines Professor Jun Li’s theoretical foundations and ideas from the syndrome differentiation and treatment of phlegm and blood stasis,systematically examines the curative effect and mechanism of Naotaitong Decoction in the treatment of vascular dementia,and examines the prescription and medication of typical cases for readers,in the hopes of providing guidance to clinical diagnosis and treatment of this disease.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.52074182,52304406 and U23A20612)the Natural Science Foundation of Shanghai(Grant Nos.22ZR1430700 and 23TS1401900)+1 种基金the National Science and Technology Major Project(No.2017-VII-0008-0102)Neng Ren acknowledges the Startup Fund for Young Faculty at SJTU.
文摘Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformation,while the mechanism has not been fully understood at the mesoscale.In this work,a model coupling dendrite growth,thermal-solutal-fluid flow,thermal stress and flow-induced dendrite deformation via cellular automaton-finite volume method and finite element method is developed to study the formation of LAGBs in single crystal superalloys.Results reveal that the bending of dendrites is primarily attributed to the thermal-solutal convection-induced dendrite deformation.The mechanical stress of dendrite deformation develops and stabilises as solidification proceeds.As the width of the mushy zone gets stable,stresses are built up and then dendritic elastoplastic bending occurs at some thin primary dendrites with the wider inter-dendritic space.There are three characteristic zones of stress distribution along the solidification direction:(i)no stress concentration in the fully solidified regions;(ii)stress developing in the primary dendrite bridging region,and(iii)stress decrease in the inter-dendritic uncontacted zone.The stresses reach maximum near the initial dendrite bridging position.The lower temperature gradients,the finer primary dendritic trunks and sudden reductions in local dendritic trunk radius jointly promote the elastoplastic deformation of the dendrites.Corresponding measures are suggested to reduce LAGBs.
基金supported by the National Natural Science Foundation of China(72374061,72204243)the Ministry of Education’s Humanities and Social Science Research Youth Fund Project(20YJC630138,22YJC630056)+1 种基金Anhui Provincial Natural Science Foundation(2208085UD02)New Liberal Arts Fund Expansion Project of University of Science and Technology of China(FSSF-A-230317).
文摘In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the research samples,this paper conducts an empirical test on the impact of the digital transformation of logistics enterprises on their green in-novation.Specifically,enterprise digital transformation indicators are constructed through the text analysis method,and the fixed-effects model is applied for analysis.The results indicate that the digital transformation of logistics enterprises has a significant promoting effect on their green innovation;the promoting effect of the digital transformation of logistics enterprises on green innovation is primarily achieved by easing corporate financing constraints and reducing corporate en-vironmental uncertainty;and the impact of digital transformation on green innovation is geographically heterogeneous.
基金supported by the National Key Research and Development Program of China(2022YFB3903505)the National Natural Science Foundation of China(72221002)。
文摘The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(N)use efficiency and reduce environmental impacts is still unclear.Here,we examined the data from 502 valid questionnaires collected from WFFPs in the major grain-producing area,the Huang-Huai-Hai Region(HHHR)in China,with 429 samples for wheat,328 for maize,and 122 for rice.We identified gaps in N use efficiency(NUE)and N losses from the production of the three crops between the sampled WFFPs and counties based on the statistical data.The results showed that compared to the county-level(wheat,39.1%;maize,33.8%;rice,35.1%),the NUEs for wheat(55.2%),maize(52.1%),and rice(50.2%)in the WFFPs were significantly improved(P<0.05).In addition,the intensities of ammonia(NH3)volatilization(9.9-12.2 kg N ha–1),N leaching(6.5-16.9 kg N ha–1),and nitrous oxide(N2O)emissions(1.2-1.6 kg N ha–1)from crop production in the sampled WFFPs were significantly lower than the county averages(P<0.05).Simulations showed that if the N rates are reduced by 10.0,15.0,and 20.0%for the counties,the NUEs of wheat,maize,and rice in the HHHR will increase by 2.9-6.3,2.4-5.2,and 2.6-5.7%,respectively.If the N rate is reduced to the WFFP level in each county,the NUEs of the three crops will increase by 12.9-19.5%,and the N leaching,NH3,and N2O emissions will be reduced by 48.9-56.2,37.4-42.9,and 46.0-66.5%,respectively.Our findings highlight that efficient N management practices in sustainable intensive farmland have considerable potential for reducing environmental impacts.
基金supported by National Natural Science Foundation of China(Nos.22325602,22176060)Program of Shanghai Academic/Technology Research Leader(No.23XD1421000)+2 种基金Project supported by Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)the Program of Introducing Talents of Discipline to Universities(No.B16017)Science and Technology Commission of Shanghai Municipality(No.20DZ2250400)。
文摘H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an innovative method for storing and releasing H_(2)O_(2)using hydrogels.Commercial hydrogels(sodium polyacrylate)can undergo swelling and absorb H_(2)O_(2)in aqueous solutions,and the swollen hydrogel can continuously release H_(2)O_(2)under osmotic pressure.And the characteristics of osmotic pressure drive ensure the recyclability of hydrogel for H_(2)O_(2)storage.Experimental results demonstrate that H_(2)O_(2)can stably exist within the hydrogel for an extended period,and this strategy helps to avoid explosion the risk and potential environmental hazards during the transportation of H_(2)O_(2).Finally,experiments confirm that the hydrogel controlled sustained release of H_(2)O_(2)is effective in both Fenton reactions and the process of bacterial inactivation.This work introduces new ideas for the storage of H_(2)O_(2),and the sustained release of H_(2)O_(2)may have significant implications in the fields of healthcare,environmental science,catalysis,and beyond.
基金supported in part by National Key R&D Program of China(Grant No.2021YFB1714100)in part by the National Natural Science Foundation of China(NSFC)under Grant 62371239+5 种基金in part by the the Program of Science and Technology Cooperation of Nanjing with International/Hong Kong,Macao and Taiwan(Grant No.202401019)in part by the Guangdong Basic and Applied Basic Research Foundation(Grant No.2024A1515012407)in part by the the Research Center for FinTech and Digital-Intelligent Management at Shenzhen University,in part by the National Natural Science Foundation of China under Grant 62271192in part by the Equipment Pre-Research Joint Research Program of Ministry of Education under Grant 8091B032129in part by the Major Science and Technology Projects of Longmen Laboratory under Grant 231100220300 and 231100220200in part by the Central Plains Leading Talent in Scientific and Technological Innovation Program under Grant 244200510048.
文摘Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has been advocated for decentralized data management in a tamper-resistance,traceable,and transparent manner.However,a major issue that hinders the integration of blockchain and IoT lies in that,it is rather challenging for resource-constrained IoT devices to perform computation-intensive blockchain consensuses such as Proof-of-Work(PoW).Furthermore,the incentive mechanism of PoW pushes lightweight IoT nodes to aggregate their computing power to increase the possibility of successful block generation.Nevertheless,this eventually leads to the formation of computing power alliances,and significantly compromises the decentralization and security of BlockChain-aided IoT(BC-IoT)networks.To cope with these issues,we propose a lightweight consensus protocol for BC-IoT,called Proof-of-Trusted-Work(PoTW).The goal of the proposed consensus is to disincentivize the centralization of computing power and encourage the independent participation of lightweight IoT nodes in blockchain consensus.First,we put forth an on-chain reputation evaluation rule and a reputation chain for PoTW to enable the verifiability and traceability of nodes’reputations based on their contributions of computing power to the blockchain consensus,and we incorporate the multi-level block generation difficulty as a rewards for nodes to accumulate reputations.Second,we model the block generation process of PoTW and analyze the block throughput using the continuous time Markov chain.Additionally,we define and optimize the relative throughput gain to quantify and maximize the capability of PoTW that suppresses the computing power centralization(i.e.,centralization suppression).Furthermore,we investigate the impact of the computing power of the computing power alliance and the levels of block generation difficulty on the centralization suppression capability of PoTW.Finally,simulation results demonstrate the consistency of the analytical results in terms of block throughput.In particular,the results show that PoTW effectively reduces the block generation proportion of the computing power alliance compared with PoW,while simultaneously improving that of individual lightweight nodes.This indicates that PoTW is capable of suppressing the centralization of computing power to a certain degree.Moreover,as the levels of block generation difficulty in PoTW increase,its centralization suppression capability strengthens.
基金supported by the Postdoctoral Fellow-ship Program of CPSF(Grant No.GZC20233105)the Science Foundation of China University of Petroleum,Beijing(Grant No.2462024XKBH006)+2 种基金the China Postdoctoral Science Foundation(Grant No.2024M753615)the Major Scientific Research Instrument Development Program of National Natural Science Foundation of China(Grant No.52227804)the Youth Science Foundation Program of National Natural Science Foundation of China(Grant No.52404012).
文摘The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In this paper,we introduce a transient wellbore multiphase flow model specifically developed to simulate gas kick in deepwater dual-gradient drilling,incorporating a downhole separator.The model accounts for the variable mass flow within the annulus and heat exchange between the annular fluid and the formation.Using this model,we analyzed the multiphase flow and thermodynamic behavior during the gas kick.Simulation results reveal a progressive increase in bottom-hole temperature,underscoring its potential as a key indicator for gas kick early detection.Additionally,variable gradient parameters affect not only the annular equivalent circulating density(ECD)profile but also the evolution of the gas kick.The inclusion of a downhole separator alters the annular ECD profile,creating a“broken line”shape,which enhances adaptability to the multi-pressure systems typically encountered in deepwater forma-tion.By adjusting factors such as hollow sphere concentration,separator position,and separation effi-ciency,the annular ECD profile can be effectively customized.This study provides important theoretical insights and practical applications for utilizing dual-gradient drilling technology to address challenges in deepwater formation drilling.
基金supported by the National Natural Science Foundation of China(Nos.12472005 and 52175079)the Aerospace Science Foundation of China(No.2022Z009050002)+2 种基金the Key Laboratory of Vibration and Control of Aero-Propulsion SystemMinistry of Education of China(No.VCAME201603)the Tai-Hang Laboratory Program(No.AK023)。
文摘This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of existing methods,a dynamic model is developed for both free and forced vibration scenarios.These models incorporate the virtual spring technology to accurately simulate a wide range of boundary conditions.Using the first-order shear deformation theory in conjunction with the Jacobi orthogonal polynomials,an energy expression is formulated,and the natural frequencies and mode shapes are determined via the Ritz method.Based on the Newmark-βmethod,the pulse response amplitudes and attenuation characteristics under various transient excitation loads are analyzed and evaluated.The accuracy of the theoretical model and the vibration suppression capability of the damping gel are experimentally validated.Furthermore,the effects of key structural parameters on the natural frequency and vibration response are systematically examined.
基金financially sponsored by the National Natural Science Foundation of China(Nos.U2441268 and 52304406)the Natural Science Foundation of Shanghai,China(No.23TS1401900)+2 种基金the Science Foundation of Aeronautics(PSSFA),China(No.2024Z053057002)the Science and Technology Cooperation Program of Shanghai Jiao Tong University in Inner Mongolia Autonomous Region-Action Plan of Shanghai Jiao Tong University for“Revitalizing Inner Mongolia through Science and Technology”,ChinaLuwei Yang would like to thank the financial support from the Chinese Scholarship Council(No.202306230337).
文摘Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencing the SX structure.Casting deformation is simulated in most of the previous studies,whereas the direct simulation of dendritic thermomechanical deformation has been largely ignored,resulting in a lack of comprehensive understanding of this process.In this study,we systematically investigate dendritic thermomechanical deformation with a model coupled with dendrite growth,fluid flow,and thermomechanical deformation behavior.Results reveal that the dendritic thermomechanical deformation-induced dendrite bending is not randomly distributed but is mainly concentrated on the casting surface.The dendritic thermal stress increases as dendrite grows and accumulates after dendrite bridging.Transverse thermal contraction mainly occurs at the edge of casting in the corner,and axial thermal contraction is larger than transverse contraction.The high-stress region of the primary dendrite trunk is mainly distributed below the dendrite bridging near the solidified part,and the stress along the transverse direction reaches its maximum value on the casting surface.Stress concentrated on the casting surface is mainly attributed to variations in transverse temperature gradients caused by heat dissipation on the lateral mold wall,and inconsistent constraints in the lateral mold walls.
文摘BACKGROUND Gastrointestinal schwannomas(GIS)are rare neurogenic tumors arising from Schwann cells in the gastrointestinal tract.Studies on GIS are limited to small case reports or focus on specific tumor sites,underscoring the diagnostic and thera-peutic challenges they pose.AIM To comprehensively examine the clinical features,pathological characteristics,treatment outcomes,associated comorbidities,and prognosis of GIS.METHODS The study population included patients diagnosed with GIS at the First Affiliated Hospital,Zhejiang University School of Medicine,between June 2007 and April 2024.Data were retrospectively collected and analyzed from medical records,including demographic characteristics,endoscopic and imaging findings,treatment modalities,pathological evaluations,and follow-up information.RESULTS In total,229 patients with GIS were included,with a mean age of 56.00 years and a male-to-female ratio of 1:1.83.The mean tumor size was 2.75 cm,and most(76.9%)were located in the stomach.Additionally,6.6%of the patients had other malig-nant tumors.Preoperative imaging and endoscopy frequently misdiagnosed GIS as gastrointestinal stromal tumors.However,accurate preoperative diagnosis was achieved using endoscopic ultrasound-guided fine-needle aspiration combined with immunohistochemical analysis,in which S100 and SOX-10 markers were mostly positive.Smaller tumors were typically managed with endoscopic resection,while larger lesions were treated with surgical resection.Follow-up results showed that most patients experienced favorable outcomes.CONCLUSION Preoperative diagnosis of GIS via clinical characteristics,endoscopy,and imaging examinations remains challenging but crucial.Endoscopic therapy provides a minimally invasive and effective option for patients.
基金supported by the National Key R&D Program of China(No.2022YFA1603102)the National Natural Science Foundation of China(NSFC,Grant Nos.U2031202,12373030,and 11873093)。
文摘The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemica properties of these sources and help us estimate their evolutionary stages.We report line detections within the 3 mm band using the FTS wide-sideband mode of the IRAM 30 m telescope toward 20 gas-infalling sources.Using XCLASS,we identify the emission lines of up to 22 molecular species(including a few isotopologues)and on hydrogen radio recombination line in these sources.H^(13)CO^(+),HCO^(+),HCN,HNC,c-C_(3)H_(2),and CCH lines are detected in 15 sources.We estimate the rotation temperatures and column densities of these molecular species using the LTE radiative transfer model,and compare the molecular abundances of these sources with those from nine high mass star-forming regions reported in previous studies and with those from the chemical model.Our results sugges that G012.79-0.20,G012.87-0.22 clump A and B,and G012.96-0.23 clump A may be in the high-mass protostella object stage,while sources with fewer detected species may be in the earlier evolutionary stage.Additionally,th CCH and c-C_(3)H_(2)column densities in our sources reveal a linear correlation,with a ratio of N(CCH)/N(c-C_(3)H_(2)=89.2±5.6),which is higher than the ratios reported in the literature.When considering only sources with lowe column densities,this ratio decreases to 29.0±6.1,consistent with those of diffuse clouds.Furthermore,comparison between the N(CCH)/N(c-C_(3)H_(2))ratio and the sources’physical parameters reveals a correlation,with sources exhibiting higher ratios tending to have higher kinetic temperatures and H2column densities.
基金supported by the National Natural Science Foundation of China(82360801,82460822)Natural Science Foundation of Inner Mongolia Autonomous Region(2022LHQN08001,2023QN08050,2025LHMS08061)+4 种基金the Scientific Research Project of Higher Education Institutions in Inner Mongolia Autonomous Region(NJZY23135)the Laboratory Open Fund of Inner Mongolia Medical University(2024ZN23)and the General Project of Inner Mongolia Medical University(YKD2025MS047Inner Mongolia Medical University Undergraduate Science and Technology Innovation"Talent Cultivation"Project(YCPY2025028,YCPY2025024)Inner Mongolia Medical University Undergraduate Innovation and Entrepreneurship Training Program Project(101322025034).
文摘Background:Bacterial pneumonia continues to be a significant global health concern,particularly among high-risk groups,necessitating the development of precise and early diagnostic biomarkers.While the efficacy of procalcitonin(PCT)and C-reactive protein(CRP)as inflammatory markers is widely recognized,their relative diagnostic performance across different age groups remains debate.This meta-analysis was designed to assess the diagnostic accuracy of PCT and CRP in bacterial pneumonia.Methods:In this meta-analysis adhering to PRISMA guidelines,we searched PubMed,Web of Science,and the Cochrane Library for relevant diagnostic accuracy studies.From 19 included studies(n=2,603),data were extracted to construct tables.Study quality was assessed with the QUADAS-2 tool.The bivariate random-effects model was employed to derive pooled sensitivity,specificity,positive and negative likelihood ratios,and summary AUCs.To explore the substantial heterogeneity(I^(2)>80%),we performed pre-specified subgroup analyses based on age demographics.Results:Our findings indicate superior diagnostic performance for PCT,evidenced by a pooled sensitivity of 0.8841 and specificity of 0.8499,relative to CRP’s sensitivity of 0.8371 and specificity of 0.7185.The area under the ROC curve(AUC)for PCT was 0.992,a value significantly higher than that of CRP(0.987).Intriguingly,subgroup analyses revealed age-dependent variations:CRP demonstrated enhanced diagnostic utility in minors,while PCT proved substantially more effective in non-elderly adults.Conclusion:These results reinforce the clinical relevance of PCT as a more dependable biomarker for bacterial pneumonia,particularly in informing antibiotic treatment and mitigating misuse.This study uniquely includes age-stratified analyses based on predefined groups(minors and non-elderly adults),providing refined insights for individualized diagnostic approaches.We propose further multicenter research endeavors to confirm threshold optimization and explore combined biomarker strategies.
基金supported by the Major Research Project on Scientific Instrument Development of the National Natural Science Foundation of China(42327901)National Natural Science Foundation of China(42030806,42074120,41904104,423B2405).
文摘The electromagnetic(EM)telemetry systems,employed for real-time data transmission from the borehole and the earth surface during drilling,are widely used in measurement-while-drilling(MWD)and logging-while-drilling(LWD).Several numerical methods,including the method of moments(MoM),the electric field integral equation(EFIE)method,and the finite-element(FE)method have been developed for the simulation of EM telemetry systems.The computational process of these methods is complicated and time-consuming.To solve this problem,we introduce an axisymmetric semi-analytical FE method(SAFEM)in the cylindrical coordinate system with the virtual layering technique for rapid simulation of EM telemetry in a layered earth.The proposed method divides the computational domain into a series of homogeneous layers.For each layer,only its cross-section is discretized,and a high-precision integration method based on Riccati equations is employed for the calculation of longitudinally homogeneous sections.The block-tridiagonal structure of the global coefficient matrix enables the use of the block Thomas algorithm,facilitating the efficient simulation of EM telemetry problems in layered media.After the theoretical development,we validate the accuracy and efficiency of our algorithm through a series of numerical experiments and comparisons with the Multiphysics modeling software COMSOL.We also discussed the impact of system parameters on EM telemetry signal and demonstrated the applicability of our method by testing it on a field dataset acquired from Dezhou,Shandong Province,China.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(No.2023B1515120030).
文摘The rapid-cycling synchrotron(RCS)is a crucial device for proton beam acceleration at the China Spallation Neutron Source,operating at a repetition frequency of 25 Hz.The beam power was increased from 100 kW to 140 kW.This increase makes the on-orbit beam more sensitive to disturbances in various parts of the accelerator,including the RCS magnet power supply system.This paper presents a method for reducing the high-order harmonic current error in resonant power supplies for dipole magnets and examines its impact on the horizontal orbit offset of the beam.It adopts a control scheme that combines high-order harmonic current compensation with PI double-loop control of the resonant power supply.By utilizing the existing digital controller hardware in the RCS power supply system,this study demonstrates how to achieve precise control of the 50 Hz harmonic current output in a cost-effective manner.Ultimately,it enhances performance by reducing the current error by up to 50%and provides methodological support for future upgrades to the power supply system.Such improvements enhance the stability of the RCS,reducing the beam horizontal orbit deviation by at least 19.8%.
基金funded by the Key Technologies R&D Program of CNBM(2023SJYL01)Postgraduate Research&Practice Innovation Program of Jiangsu Province(SJCX24_1356).
文摘Throughout the composite structure’s lifespan,it is subject to a range of environmental factors,including loads,vibrations,and conditions involving heat and humidity.These factors have the potential to compromise the integrity of the structure.The estimation of the fatigue life of composite materials is imperative for ensuring the structural integrity of these materials.In this study,a methodology is proposed for predicting the fatigue life of composites that integrates ultrasonic guided waves and machine learning modeling.The method first screens the ultrasonic guided wave signal features that are significantly affected by fatigue damage.Subsequently,a covariance analysis is conducted to reduce the redundancy of the feature matrix.Furthermore,one-hot encoding is employed to incorporate boundary conditions as features,and the resulting data undergoes preprocessing to form a sample library.A composite fatigue life prediction model has been developed,employing the aforementioned sample library as the input source and utilizing remaining life as the output metric.The model synthesizes the strengths of convolutional neural networks(CNNs)and bidirectional long short-term memory networks(BiLSTMs)while leveraging Bayesian optimization(BO)to enhance the optimization of hyperparameters.The experimental results demonstrate that the proposed BO-CNN-BiLSTM model exhibits superior performance in terms of prediction accuracy and reliability in the damage regression task when compared to both the BiLSTM and CNN-BiLSTM models.
基金funded by the National Natural Science Foundation of China(32071921)Key R&D Program of Shandong Province,China(2021LZGC022)Taishan Scholars Project(ts201712024).
文摘Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.
基金Supported by Construction Project of High-quality Vegetable Quality Characteristic Index System in Hebei Province.
文摘Vegetables are essential and important foods in people s daily production,which are closely related to human health.Focusing on the present situation of vegetable nutrition and safety quality detection from detection indexes and detection methods,this paper discussed the selection of detection indexes and detection methods for vegetable nutrition and safety quality,and put forward the main research direction of vegetable nutrition and safety quality detection in the future,providing guidance and reference for improving vegetable nutrition and safety quality evaluation.
基金supported by the National Natural Science Foundation of China(Grant numbers:52174012,52394250,52394255,52234002,U22B20126,51804322).
文摘Formation pore pressure is the foundation of well plan,and it is related to the safety and efficiency of drilling operations in oil and gas development.However,the traditional method for predicting formation pore pressure involves applying post-drilling measurement data from nearby wells to the target well,which may not accurately reflect the formation pore pressure of the target well.In this paper,a novel method for predicting formation pore pressure ahead of the drill bit by embedding petrophysical theory into machine learning based on seismic and logging-while-drilling(LWD)data was proposed.Gated recurrent unit(GRU)and long short-term memory(LSTM)models were developed and validated using data from three wells in the Bohai Oilfield,and the Shapley additive explanations(SHAP)were utilized to visualize and interpret the models proposed in this study,thereby providing valuable insights into the relative importance and impact of input features.The results show that among the eight models trained in this study,almost all model prediction errors converge to 0.05 g/cm^(3),with the largest root mean square error(RMSE)being 0.03072 and the smallest RMSE being 0.008964.Moreover,continuously updating the model with the increasing training data during drilling operations can further improve accuracy.Compared to other approaches,this study accurately and precisely depicts formation pore pressure,while SHAP analysis guides effective model refinement and feature engineering strategies.This work underscores the potential of integrating advanced machine learning techniques with domain-specific knowledge to enhance predictive accuracy for petroleum engineering applications.
基金supported by the National Natural Science Foundation of China(52272088,52072273 and 51972239)the Zhejiang Provincial Natural Science Foundation of China(LZ21E020001)the Key Lab of Advanced Energy Storage and Conversion(2021HZSY0051)。
文摘Organic cathode materials exhibit higher energy storage capacity,their poor cyclability due to dissolution in liquid organic electrolytes remains a challenge.However,recently,the electrochemical behavior of organopolysulfides incorporating N-heterocycles unveils promising cathode materials with stable cycling performance.Herein,the integration of organosulfides salt as cathodes with solid electrolytes,exemplified by sodium allyl(methyl)carbamodithioate and sodium diethylcarbamodithioate with a polymer solid electrolyte of polyethylene oxide and LiTFSI,addresses the poor electrochemical stability of organic electrodes.Comparative analysis highlights sodium allyl(methyl)carbamodithioate's superior electrochemical performance and stability compared with sodium diethylcarbamodithioate,emphasizing the efficacy of periphery aliphatic modification in enhancing electrode capacity,rate performance,and electrochemical stability for organosulfide materials within all-solid-state lithium organic batteries.We also explore the origin of periphery aliphatic modification in these enhancing electrochemical performances by kinetic analysis and thermodynamic analysis.Furthermore,employing density functional theory calculations and ex situ FTIR experiments elucidates the critical role of the N-C=S structure in the energy storage mechanism.This research advances organic cathode design within organosulfide materials,unlocking the potential of allsolid-state lithium organic batteries with enhanced cyclability,propelling the development of next-generation energy storage systems.
基金supported by the National Natural Science Foundation of China(Nos.22279101,22172117 and 52072298)Foshan Science and Technology Innovation Team Project(No.1920001004098)+1 种基金Scientific Research Program Funded by Education Department of Shaanxi Provincial Government(No.22JP056)the Natural Science Basic Research Program of Shaanxi(No.2024JC-YBQN-0141).
文摘Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory electrochemical performance.In this study,CoF_(2)was combined with carbonaceous materials to obtain graphitic carbon-encapsulated CoF_(2)nanoparticles uniformly embedded in an interconnected N-doped carbon matrix(CoF_(2)@NC),significantly boosting the inert kinetics and electronic conductivity.The CoF_(2)@NC nanocomposites exhibited a notable reversible capacity of 352.0 mAh·g^(-1)at 0.2 A·g^(-1).Notably,it maintained superior long-term cycling stability even at a high current density of 2 A·g^(-1),with a capacity of 235.5 mAh·g^(-1)after 1200 cycles,evidently exceeding that of commercially available CoF_(2)electrodes.Kinetic analysis indicated that the enhanced electrochemical performance originated from the increased contribution of capacitive effects.Furthermore,in-situ electrochemical impedance spectroscopy(EIS)results verify that the improved cycling performance is associated with the enhanced interfacial stability of CoF_(2)@NC.This research not only proposes a solution for the challenges of conversion cathodes in lithium-ion batteries,but also offers novel synthesis strategies for designing high-energy metal fluoride materials.
