Lateral flow immunoassay(LFIA),a rapid detection technique noted for simplicity and economy,has showcased indispensable applicability in diverse domains such as disease screening,food safety,and environmental monitori...Lateral flow immunoassay(LFIA),a rapid detection technique noted for simplicity and economy,has showcased indispensable applicability in diverse domains such as disease screening,food safety,and environmental monitoring.Nevertheless,challenges still exist in detecting ultra-low concentration analytes due to the inherent sensitivity limitations of LFIA.Recently,significant advances have been achieved by integrating enzyme activity probes and transforming LFIA into a highly sensitive tool for rapidly detecting trace analyte concentrations.Specifically,modifying natural enzymes or engineered nanozymes allows them to function as immune probes,directly catalyzing the production of signal molecules or indirectly initiating enzyme activity.Therefore,the signal intensity and detection sensitivity of LFIA are markedly elevated.The present review undertakes a comprehensive examination of pertinent research literature,offering a systematic analysis of recently proposed enzyme-based signal amplification strategies.By way of comparative assessment,the merits and demerits of current approaches are delineated,along with the identification of research avenues that still need to be explored.It is anticipated that this critical overview will garner considerable attention within the biomedical and materials science communities,providing valuable direction and insight toward the advancement of high-performance LFIA technologies.展开更多
Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling a...Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling among patients with IBD from July 2022 to July 2023.Patients were assessed using the Generalized Social Alienation Scale(GSAS),the Brief Illness Perception Questionnaire(B-IPQ),the Hospital Anxiety and Depression Scale(HADS),and the Medical Coping Modes Questionnaire(MCMQ).Demographic and disease-related characteristics were also collected.Latent profileanalysis(LPA)was used to identify potential subgroups of social alienation.Univariate analysis and multicollinearity analysis were conducted to explore the influencing factors,followed by multiple regression analysis to evaluate the effect of influencingfactors on social alienation.Results:Three distinct profilesof social alienation were identified:integrated-low alienation group(n=61,20.20%),accommodative-moderate alienation group(n=195,64.57%),and maladaptive-high alienation group(n=46,15.23%).Seven characteristics were associated with the profile’smembership:self-perceived financialstress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode.Conclusions:Patients with IBD were categorized into three subgroups based on social alienation levels.Financial stress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode were key predictors of the subgroup membership.Targeted interventions should be developed to mitigate the negative effects of social alienation,with a focus on improving illness perception,alleviating anxiety and depression,and promoting effective coping strategies.展开更多
Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method bas...Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method based on the Mask-RCNN framework. A dataset of 9880 high-resolution images was captured by using a self-made fiber-optic endoscopic system for 13 kinds of silicoaluminophosphate-34 (SAPO-34) catalyst samples with different coke. Then there were approximately 877881 individual particles extracted from this dataset by our AI-based particle recognition algorithm. To clearly describe the morphology of irregular particles, we proposed a hybrid classification criterion that combines five different parameters, which are deformity, circularity, roundness, aspect ratio, and compactness. Therefore, catalyst morphology can be classified into two categories with four types. The first category includes regular types, such as the spherical, ellipsoidal, and rod-shaped types. And all the irregular types fall into the second category. The experimental results showed that a catalyst particle tends to be larger when its coke deposition increased. Whereas particle morphology remained primarily spherical and ellipsoidal, the ratio of each type varied slightly according to its coke. Our findings illustrate that this is a promising approach to be developing intelligent instruments for catalyst particle sizing and classification.展开更多
Performance breakthrough of electrocatalysts highly relies on the regulation of internal structures and electronic states.In present work,for the first time,we successfully synthesized nitrogen doped FeS_(2) nanoparti...Performance breakthrough of electrocatalysts highly relies on the regulation of internal structures and electronic states.In present work,for the first time,we successfully synthesized nitrogen doped FeS_(2) nanoparticles(N-FeS_(2))as the electrocatalysts for hydrogen evolution reaction(HER).The band structure and electronic state of FeS_(2) are modulated by a nitrogen doping strategy,as confirmed by X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS)and density functional theory(DFT)calculations.Owing to the band structure and electronic state regulation as well as the weakening of H-S interaction,the designed N-FeS_(2) electrocatalyst exhibits superior catalytic performance with a low overpotential(~126 mV at 10 mA cm^(-2))and excellent activity stability under alkaline conditions,which is substantially improved as compared with that of the pure FeS_(2) counterpart.Our work demonstrates that the modulation of electron state and band structure of an electrocatalyst,which can provide a valuable guidance for designing excellent catalysts for hydrogen evolution reaction and beyond.展开更多
The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)signific...The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO_(2) reduction into syngas.During photocatalytic CO_(2) reduction,Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85μmol gcat^(−1)h^(−1) and continuously adjustable CO/H_(2) ratios ranging from 5:1 to 1:2,which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts.Mechanistic studies reveal that P doping improves the conductivity of catalysts,which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites,facilitating the CO_(2)‐to‐syngas photoreduction process.展开更多
Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,pre...Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,prevention,and treatment.Generalized linear mixed models(GLMM)is an extension of linear model for categorical responses while considering the correlation among observations.Methods Magnetic resonance image(MRI)data of carotid atheroscleroticplaques were acquired from 20 patients with consent obtained and 3D thin-layer models were constructed to calculate plaque stress and strain for plaque progression prediction.Data for ten morphological and biomechanical risk factors included wall thickness(WT),lipid percent(LP),minimum cap thickness(MinCT),plaque area(PA),plaque burden(PB),lumen area(LA),maximum plaque wall stress(MPWS),maximum plaque wall strain(MPWSn),average plaque wall stress(APWS),and average plaque wall strain(APWSn)were extracted from all slices for analysis.Wall thickness increase(WTI),plaque burden increase(PBI)and plaque area increase(PAI) were chosen as three measures for plaque progression.Generalized linear mixed models(GLMM)with 5-fold cross-validation strategy were used to calculate prediction accuracy for each predictor and identify optimal predictor with the highest prediction accuracy defined as sum of sensitivity and specificity.All 201 MRI slices were randomly divided into 4 training subgroups and 1 verification subgroup.The training subgroups were used for model fitting,and the verification subgroup was used to estimate the model.All combinations(total1023)of 10 risk factors were feed to GLMM and the prediction accuracy of each predictor were selected from the point on the ROC(receiver operating characteristic)curve with the highest sum of specificity and sensitivity.Results LA was the best single predictor for PBI with the highest prediction accuracy(1.360 1),and the area under of the ROC curve(AUC)is0.654 0,followed by APWSn(1.336 3)with AUC=0.6342.The optimal predictor among all possible combinations for PBI was the combination of LA,PA,LP,WT,MPWS and MPWSn with prediction accuracy=1.414 6(AUC=0.715 8).LA was once again the best single predictor for PAI with the highest prediction accuracy(1.184 6)with AUC=0.606 4,followed by MPWSn(1. 183 2)with AUC=0.6084.The combination of PA,PB,WT,MPWS,MPWSn and APWSn gave the best prediction accuracy(1.302 5)for PAI,and the AUC value is 0.6657.PA was the best single predictor for WTI with highest prediction accuracy(1.288 7)with AUC=0.641 5,followed by WT(1.254 0),with AUC=0.6097.The combination of PA,PB,WT,LP,MinCT,MPWS and MPWS was the best predictor for WTI with prediction accuracy as 1.314 0,with AUC=0.6552.This indicated that PBI was a more predictable measure than WTI and PAI. The combinational predictors improved prediction accuracy by 9.95%,4.01%and 1.96%over the best single predictors for PAI,PBI and WTI(AUC values improved by9.78%,9.45%,and 2.14%),respectively.Conclusions The use of GLMM with 5-fold cross-validation strategy combining both morphological and biomechanical risk factors could potentially improve the accuracy of carotid plaque progression prediction.This study suggests that a linear combination of multiple predictors can provide potential improvement to existing plaque assessment schemes.展开更多
Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to ...Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.展开更多
Potassium ions(K+),the pivotal cations for membrane potential,are particularly important for maintaining the physiological function of neurons[1].When the concentration of extracellular K+([K+]o)is pathologically chan...Potassium ions(K+),the pivotal cations for membrane potential,are particularly important for maintaining the physiological function of neurons[1].When the concentration of extracellular K+([K+]o)is pathologically changed,the intrinsic neuronal excitability and synaptic transmission are also altered,which have profound implications for many neurological disorders such as epilepsy,Parkinson's disease,and emotional disorders[2-4].展开更多
Background:Esophageal cancer(ESCA)is a common digestive tract tumor.As a result,optimization of the early diagnosis of ESCA and identifying the contributing prognostic genes is urgently required.Herein,the prognosis o...Background:Esophageal cancer(ESCA)is a common digestive tract tumor.As a result,optimization of the early diagnosis of ESCA and identifying the contributing prognostic genes is urgently required.Herein,the prognosis of mitochondrial autophagy-related genes was analyzed in different subtypes of ESCA,and prognostic models were constructed to identify the immune cell infiltration with significant differences between subtypes.Methods:The Cancer Genome Atlas database was searched to download 185 ESCA samples,covering gene expression level data and clinical follow-up data,and 179 samples from the Gene Expression Omnibus database for subsequent validation analysis.The consensus Cluster Plus analysis method was employed to identify the best mitochondrial autophagy subtype.Kaplan-Meier curve was used to evaluate the correlation of survival prognosis between different subtype groups and actual survival prognostic information.A chi-square test was performed to analyze the correlation between subtypes and clinical information.Differential genetic analysis between different subtypes was performed using Limma packs(threshold setting:adj.p<0.05&|log2FC|>1).Univariate Cox regression analysis was applied to identifying genes with significant prognosis,and the LASSO algorithm screened out key genes.The risk scores were constructed by Stepwise Cox regression analysis and divided into high and low-risk groups.Independent prognostic factors were determined using the univariate and nomograms constructed by multivariate Cox analysis.The CIBERSORT method was used to calculate the composition ratio of 22 immune cells;the matrix and immune scores of tumor samples were calculated by the ESTIMATE algorithm.Wilcoxon’s test was performed to compare the expression differences of immune checkpoint genes and human leukocyte antigen family genes between high-and low-risk groups and the difference in IC50 between these risk groups of 138 chemotherapy drugs.Relationships between mitochondrial autophagy subtypes and high-and low-risk groups were assessed using the ggalluvial package in R3.6.1.Results:Seven mitochondrial autophagy genes associated with the of ESCA were identified(PTPN4,ALKBH4,IL6,FN3KRP,HSDL1,B3GNT2,CCT4).High and low risk were significantly correlated with the actual prognosis.Nomograms constructed by factors stage and Risk group showed significant relation with patient prognosis.Eleven immune cells significantly differing in the two subtypes were identified,followed by ten significantly different immune checkpoint genes.Conclusion:Seven mitochondrial autophagy genes associated with the prognosis of ESCA may serve as the key prognostic genes and novel therapeutic targets for esophageal cancer.展开更多
Improving the computational efficiency of multi-physics simulation and constructing a real-time online simulation method is an important way to realise the virtual-real fusion of entities and data of power equipment w...Improving the computational efficiency of multi-physics simulation and constructing a real-time online simulation method is an important way to realise the virtual-real fusion of entities and data of power equipment with digital twin.In this paper,a datadriven fast calculation method for the temperature field of resin impregnated paper(RIP)bushing used in converter transformer valve-side is proposed,which combines the data dimensionality reduction technology and the surrogate model.After applying the finite element algorithm to obtain the temperature field distribution of RIP bushing under different operation conditions as the input dataset,the proper orthogonal decomposition(POD)algorithm is adopted to reduce the order and obtain the low-dimensional projection of the temperature data.On this basis,the surrogate model is used to construct the mapping relationship between the sensor monitoring data and the low-dimensional projection,so that it can achieve the fast calculation and reconstruction of temperature field distribution.The results show that this method can effectively and quickly calculate the overall temperature field distribution of the RIP bushing.The maximum relative error and the average relative error are less than 4.5%and 0.25%,respectively.The calculation speed is at the millisecond level,meeting the needs of digitalisation of power equipment.展开更多
Resin impregnated paper(RIP)converter transformer valve-side bushings are the key equipment in converter stations.Local overheating of the RIP core not only reduces the transmission efficiency but also causes insulati...Resin impregnated paper(RIP)converter transformer valve-side bushings are the key equipment in converter stations.Local overheating of the RIP core not only reduces the transmission efficiency but also causes insulation failure of converter transformers.In this paper,a new heat dissipation structure is proposed to improve the temperature distribution homogeneity of the bushing using two-phase closed thermosyphon(TPCT).A test model is developed to determine the optimal working fluid inventory.Then,the temperature distribution of a±400-kV RIP converter transformer valve-side bushing with an optimised heat dissipation structure is obtained using the coupled three-dimensional electromagnetic-fluid-thermal numerical simulation method considering multiphase flow and phase change processes.The influence of the new structure on the electric field is analysed.The simulation result is verified by the temperature rise test.The results show that two-phase closed thermosyphon can reduce the maximum temperature of the RIP valve-side bushings and significantly improve the temperature distribution homogeneity.展开更多
Rapid urbanization in China presents complex challenges for urban development,particularly in older neighborhoods.The rise of digital cities and the shift from expansion to optimizing existing urban areas have highlig...Rapid urbanization in China presents complex challenges for urban development,particularly in older neighborhoods.The rise of digital cities and the shift from expansion to optimizing existing urban areas have highlighted significant issues related to infrastructure,regeneration,and the preservation of local characteristics.These challenges hinder sustainable urban development and negatively impact residents’quality of life,making the transition to smart cities imperative.This study uses Suzhou’s old neighborhoods as a case study,employing big data and Geographic Information System(GIS)software to conduct a comprehensive quantitative assessment.Techniques such as kernel density and accessibility analysis reveal key issues in infrastructure,sustainability,and local characteristics,providing a data foundation for targeted strategies.Based on these findings,the paper proposes micro-renovation strategies aimed at enhancing community functionality and improving residents’quality of life through refined management.The study underscores that,under the“ecological+digital”sustainable development framework,renewing old neighborhoods can address existing challenges while revitalizing cities towards smarter,greener,and more livable futures.展开更多
Flexible photodetector(PD)arrays have the potential to replace the rods and cones in the retina,converting external light signals into electrical signals and offering hope for blind patients to regain vision.However,i...Flexible photodetector(PD)arrays have the potential to replace the rods and cones in the retina,converting external light signals into electrical signals and offering hope for blind patients to regain vision.However,issues like discontinuous electrode surfaces and incompletely crystallized perovskites can cause cracks and degrade the performance of flexible PDs during repeated bending,hindering their development and applications.In this study,we employ a combination of radio frequency magnetron sputtering and angular ion beam polishing to achieve an ultrathin,ultrasmooth platinum(Pt)electrode film(UTPF)with a thickness of less than 10 nm.Building on this,a vapor deposition method with dynamically regulated evaporation rates is developed to obtain a dense-gradient PbI_(2)precursor.This funnel-shaped vertical structure precursor facilitates the penetration of CH_(3)NH_(3)I solution,ultimately resulting in a dense and uniform perovskite film with large grains and strong interfacial bonding with UTPF.The results indicate that the flexible PD arrays exhibit excellent optoelectronic performances,characterized by high sensitivity,detectivity and a large on/off current ratio.Furthermore,benefitting from their exceptional flexibility and electrical stability,the devices retain 92.53%of the original photocurrent after 4000 bending cycles at large angles.Notably,the integrated 10×10 flexible PD arrays demonstrate good uniformity in dark current and photocurrent,along with high imaging resolution,showing the reliable imaging capabilities of the flexible arrays and their potential applications in artificial retina.展开更多
Background:The ASTRUM-005 study previously demonstrated a signifi-cant overall survival(OS)benefit with serplulimab(a programmed death1 inhibitor)plus chemotherapy versus chemotherapy alone in previouslyuntreated exte...Background:The ASTRUM-005 study previously demonstrated a signifi-cant overall survival(OS)benefit with serplulimab(a programmed death1 inhibitor)plus chemotherapy versus chemotherapy alone in previouslyuntreated extensive-stage small-cell lung cancer(ES-SCLC).Here,we reportupdated efficacy and safety results after an extended median follow-up of 19.8months,along with the first report on findings from exploratory biomarkeranalyses.Methods:A total of 585 patients were randomized in a 2:1 ratio to receive4.5 mg/kg serplulimab(n=389)or placebo(n=196)intravenously every 3weeks,together with carboplatin and etoposide.The primary endpoint was OS.In addition,genomic profiling was performed to identify mutated genes,and quantitative serum proteome profiling was conducted to identify differ-entially expressed proteins(DEPs)between responders and non-responders ofserplulimab plus chemotherapy.Regression analysis was subsequently used toconstruct a protein signature based on the DEPs.The associations betweenefficacy outcomes(objective response rate[ORR],OS,and progression-free sur-vival[PFS])and gene mutation status or DEP expression were also examinedwith regression analysis.Furthermore,the prognostic value of hematologicalparameters was evaluated.Results:In the intent-to-treat population,the median OS was 15.8 monthsin the serplulimab group versus 11.1 months in the placebo group(haz-ard ratio,0.62;95%confidence interval,0.50-0.76;P<0.001).We identified181 DEPs between responders and non-responders in the serplulimab group,from which a 15-protein signature was constructed.In the serplulimab group,patients with a higher 15-protein signature score were associated with sig-nificantly longer OS and PFS.Also,patients harboring tumor-suppressorretinoblastoma-1(RB1)mutations or mutations in Notch pathway membersshowed improved ORR,OS,or PFS compared with their wild-type counter-parts.Baseline neutrophil-to-lymphocyte ratio(NLR)and lactate dehydrogenase(LDH)level were independent prognosticators of patients with ES-SCLC.Conclusions:First-line serplulimab provided a sustained clinical benefit overplacebo in patients with ES-SCLC.A 15-protein signature and mutations in RB1or Notch pathway genes may serve as predictive biomarkers for benefits fromserplulimab plus chemotherapy,while baseline NLR and LDH were independentprognosticators for ES-SCLC.展开更多
Photocatalytic urea production from nitrogen(N_(2))and carbon dioxide(CO_(2))is a sustainable and ecofriendly alternative to the Bosch-Meiser route.However,it remains a significant challenge in developing highly effic...Photocatalytic urea production from nitrogen(N_(2))and carbon dioxide(CO_(2))is a sustainable and ecofriendly alternative to the Bosch-Meiser route.However,it remains a significant challenge in developing highly efficient photocatalysts for enhancing C-N coupling to high-yield urea synthesis.Herein,we propose a multi-site photocatalyst concept to address the concern of low yield by simultaneously improving photogenerated carrier separation and reactant activation.As a proof of concept,a well-defined multisite photocatalyst,Ru nanoparticles and Cu single atoms decorated CeO_(2)nanorods(Ru-Cu/CeO_(2)),is developed for efficient urea production.The incorporation of Ru and Cu sites is crucial not only to generate high-density photogenerated electrons,but also to facilitate N_(2)and CO_(2)adsorption and conversion.The in situ formed local nitrogen-rich area at Ru sites increases the encounter possibility with the carbon-containing species generated from Cu sites,substantially promoting C-N coupling.The Ru-Cu/CeO_(2)photocatalyst exhibits an impressive urea yield rate of 16.7μmol g^(-1)h^(-1),which ranks among the best performance reported to date.This work emphasizes the importance of multi-site catalyst design concept in guaranteeing rapid C-N coupling in photocatalytic urea synthesis and beyond.展开更多
Water quality prediction is vital for solving water pollution and protecting the water environment.In terms of the characteristics of nonlinearity,instability,and randomness of water quality parameters,a short-term wa...Water quality prediction is vital for solving water pollution and protecting the water environment.In terms of the characteristics of nonlinearity,instability,and randomness of water quality parameters,a short-term water quality prediction model was proposed based on variational mode decomposition(VMD)and improved grasshopper optimization algorithm(IGOA),so as to optimize long short-term memory neural network(LSTM).First,VMD was adopted to decompose the water quality data into a series of relatively stable components,with the aim to reduce the instability of the original data and increase the predictability,then each component was input into the iGOA-LSTM model for prediction.Finally,each component was added to obtain the predicted values.In this study,the monitoring data from Dayangzhou Station and Shengmi Station of the Ganjiang River was used for training and prediction.The experimental results showed that the prediction accuracy of the VMDIGOA-LSTM model proposed was higher than that of the integrated model of Ensemble Empirical Mode Decomposition(EEMD),the integrated model of Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN),Nonlinear Autoregressive Network with Exogenous Inputs(NARX),Recurrent Neural Network(RNN),as well as other models,showing better performance in short-term prediction.The current study will provide a reliable solution for water quality prediction studies in other areas.展开更多
Gas-filled internal crack might appear in thermoset materials like epoxy resin during the equipment manufacturing,which would become a vulnerable local region to initiate the electrical tree,thus prone to cause insula...Gas-filled internal crack might appear in thermoset materials like epoxy resin during the equipment manufacturing,which would become a vulnerable local region to initiate the electrical tree,thus prone to cause insulation failure.The withstand voltage test was carried on epoxy samples with artificial cracks based on a rod-plane electrode arrange-ment.Simultaneously,surface state variation and tree evolution with crack were observed by an optical microscope in conjunction with a charge-coupled device camera.The changes in morphology and chemical status of the crack surface were characterized by scanning electron microscopy,laser Raman spectrometer and energy dispersive spec-trometer,respectively.It was found that the erosion and tree started from the borderline of crack under a relatively low electric field strength;however,the area near the electrode had relatively little damage.The breaking of epoxy molecular chains coarsens the crack surface and further forms deep channels on a micro-level,which is the forerunner of the electrical tree inception.Based on these,the initiation mechanisms of the crack-induced electrical tree and the reasons for the erosion near the borderline have been revealed.This study provides a train thought for the polymer degradation opening up into the initial tree channel during tree evolution processes.展开更多
A wireless signal transmission technology based on acoustic carrier is proposed,which overcomes the limitation of electromagnetic signal shielding and shows great potential for in-site monitoring of sliding electrical...A wireless signal transmission technology based on acoustic carrier is proposed,which overcomes the limitation of electromagnetic signal shielding and shows great potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear(GIS)/gasinsulated transmission line(GIL).Here,the state parameter of the sliding electrical contact is modulated onto the frequency domain of an ultrasound wave.As a mechanical wave,the ultrasonic wave is immune to electromagnetic shielding,so that it could carry the sensing signal to penetrate the metal shielding layer and transmit to the external terminals of GIS/GIL.The principle and signal modulation process of the acoustic carrier based transmission system have been demonstrated in detail.Both simulation and experiment have been conducted to analyse the system characteristics as well as optimise the system configuration.As a proof-of-concept application,the in situ and on-line monitoring of the thermal rise of a slide electrical contact both in a current loading equivalent model and a prototype of GIS is demonstrated.Experimental results fit well with the physical process,and show a good measurement accuracy of 0.6%and tem-perature sensitivity of 400 Hz/℃.展开更多
基金Financial supports from the National Natural Science Foundation of China(NSFC,Nos.52272144 and 22205048)Heilongjiang Provincial Natural Science Foundation of China(No.JQ2022E001)+3 种基金China Postdoctoral Science Foundation(Nos.2022M710931 and 2023T160154)Heilongjiang Postdoctoral Science Foundation(No.LBH-Z22010)Natural Science Foundation of Shandong Province(No.ZR2020ZD42)the Fundamental Research funds for the Central Universities are greatly acknowledged.
文摘Lateral flow immunoassay(LFIA),a rapid detection technique noted for simplicity and economy,has showcased indispensable applicability in diverse domains such as disease screening,food safety,and environmental monitoring.Nevertheless,challenges still exist in detecting ultra-low concentration analytes due to the inherent sensitivity limitations of LFIA.Recently,significant advances have been achieved by integrating enzyme activity probes and transforming LFIA into a highly sensitive tool for rapidly detecting trace analyte concentrations.Specifically,modifying natural enzymes or engineered nanozymes allows them to function as immune probes,directly catalyzing the production of signal molecules or indirectly initiating enzyme activity.Therefore,the signal intensity and detection sensitivity of LFIA are markedly elevated.The present review undertakes a comprehensive examination of pertinent research literature,offering a systematic analysis of recently proposed enzyme-based signal amplification strategies.By way of comparative assessment,the merits and demerits of current approaches are delineated,along with the identification of research avenues that still need to be explored.It is anticipated that this critical overview will garner considerable attention within the biomedical and materials science communities,providing valuable direction and insight toward the advancement of high-performance LFIA technologies.
基金supported by the“333 High-Level Talents Training Project”of Jiangsu province(No.BRA2020069)。
文摘Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling among patients with IBD from July 2022 to July 2023.Patients were assessed using the Generalized Social Alienation Scale(GSAS),the Brief Illness Perception Questionnaire(B-IPQ),the Hospital Anxiety and Depression Scale(HADS),and the Medical Coping Modes Questionnaire(MCMQ).Demographic and disease-related characteristics were also collected.Latent profileanalysis(LPA)was used to identify potential subgroups of social alienation.Univariate analysis and multicollinearity analysis were conducted to explore the influencing factors,followed by multiple regression analysis to evaluate the effect of influencingfactors on social alienation.Results:Three distinct profilesof social alienation were identified:integrated-low alienation group(n=61,20.20%),accommodative-moderate alienation group(n=195,64.57%),and maladaptive-high alienation group(n=46,15.23%).Seven characteristics were associated with the profile’smembership:self-perceived financialstress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode.Conclusions:Patients with IBD were categorized into three subgroups based on social alienation levels.Financial stress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode were key predictors of the subgroup membership.Targeted interventions should be developed to mitigate the negative effects of social alienation,with a focus on improving illness perception,alleviating anxiety and depression,and promoting effective coping strategies.
基金supported by the National Natural Science Foundation of China(22308348)the Natural Science Foundation of Liaoning Province of China(2024-MSBA-65)+1 种基金the Qin Chuangyuan Project for Introducing High-Level Innovative and Entrepreneurial Talents(QCYRCXM-2023-024)the Energy Revolution S&T Program of Yulin Innovation Institute of Clean Energy(E201041206).
文摘Accurately acquiring catalyst size and morphology is essential for supporting catalytic reaction process design and optimal control. We report an intelligent catalyst sizing and morphological classification method based on the Mask-RCNN framework. A dataset of 9880 high-resolution images was captured by using a self-made fiber-optic endoscopic system for 13 kinds of silicoaluminophosphate-34 (SAPO-34) catalyst samples with different coke. Then there were approximately 877881 individual particles extracted from this dataset by our AI-based particle recognition algorithm. To clearly describe the morphology of irregular particles, we proposed a hybrid classification criterion that combines five different parameters, which are deformity, circularity, roundness, aspect ratio, and compactness. Therefore, catalyst morphology can be classified into two categories with four types. The first category includes regular types, such as the spherical, ellipsoidal, and rod-shaped types. And all the irregular types fall into the second category. The experimental results showed that a catalyst particle tends to be larger when its coke deposition increased. Whereas particle morphology remained primarily spherical and ellipsoidal, the ratio of each type varied slightly according to its coke. Our findings illustrate that this is a promising approach to be developing intelligent instruments for catalyst particle sizing and classification.
基金supported by National Key R&D Program of China(2017YFA0403402,2017YFA0700104)the National Natural Science Foundation of China(Grant Nos.11875258 and U1732232)+2 种基金the DNL Cooperation Fund,CAS(DNL180201)the Fundamental Research Funds for the Central Universities(Nos.WK2060190081)Users with Excellence Program of Hefei Science Center CAS(Nos.2018HSC-UE003 and 2019HSC-UE004)。
文摘Performance breakthrough of electrocatalysts highly relies on the regulation of internal structures and electronic states.In present work,for the first time,we successfully synthesized nitrogen doped FeS_(2) nanoparticles(N-FeS_(2))as the electrocatalysts for hydrogen evolution reaction(HER).The band structure and electronic state of FeS_(2) are modulated by a nitrogen doping strategy,as confirmed by X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS)and density functional theory(DFT)calculations.Owing to the band structure and electronic state regulation as well as the weakening of H-S interaction,the designed N-FeS_(2) electrocatalyst exhibits superior catalytic performance with a low overpotential(~126 mV at 10 mA cm^(-2))and excellent activity stability under alkaline conditions,which is substantially improved as compared with that of the pure FeS_(2) counterpart.Our work demonstrates that the modulation of electron state and band structure of an electrocatalyst,which can provide a valuable guidance for designing excellent catalysts for hydrogen evolution reaction and beyond.
基金Fundamental Research Funds for the Central Universities,Grant/Award Number:WK2060000016National Natural Science Foundation of China,Grant/Award Numbers:12222508,U1932213+2 种基金Youth Innovation Promotion Association of the Chinese Academy of Sciences,Grant/Award Number:2020454USTC Research Funds of the Double First‐Class Initiative,Grant/Award Number:YD2310002005National Key R&D Program of China,Grant/Award Number:2023YFA1506304。
文摘The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO_(2) reduction into syngas.During photocatalytic CO_(2) reduction,Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85μmol gcat^(−1)h^(−1) and continuously adjustable CO/H_(2) ratios ranging from 5:1 to 1:2,which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts.Mechanistic studies reveal that P doping improves the conductivity of catalysts,which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites,facilitating the CO_(2)‐to‐syngas photoreduction process.
基金supported in part by National Sciences Foundation of China grant ( 11672001)Jiangsu Province Science and Technology Agency grant ( BE2016785)supported in part by Postgraduate Research & Practice Innovation Program of Jiangsu Province grant ( KYCX18_0156)
文摘Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,prevention,and treatment.Generalized linear mixed models(GLMM)is an extension of linear model for categorical responses while considering the correlation among observations.Methods Magnetic resonance image(MRI)data of carotid atheroscleroticplaques were acquired from 20 patients with consent obtained and 3D thin-layer models were constructed to calculate plaque stress and strain for plaque progression prediction.Data for ten morphological and biomechanical risk factors included wall thickness(WT),lipid percent(LP),minimum cap thickness(MinCT),plaque area(PA),plaque burden(PB),lumen area(LA),maximum plaque wall stress(MPWS),maximum plaque wall strain(MPWSn),average plaque wall stress(APWS),and average plaque wall strain(APWSn)were extracted from all slices for analysis.Wall thickness increase(WTI),plaque burden increase(PBI)and plaque area increase(PAI) were chosen as three measures for plaque progression.Generalized linear mixed models(GLMM)with 5-fold cross-validation strategy were used to calculate prediction accuracy for each predictor and identify optimal predictor with the highest prediction accuracy defined as sum of sensitivity and specificity.All 201 MRI slices were randomly divided into 4 training subgroups and 1 verification subgroup.The training subgroups were used for model fitting,and the verification subgroup was used to estimate the model.All combinations(total1023)of 10 risk factors were feed to GLMM and the prediction accuracy of each predictor were selected from the point on the ROC(receiver operating characteristic)curve with the highest sum of specificity and sensitivity.Results LA was the best single predictor for PBI with the highest prediction accuracy(1.360 1),and the area under of the ROC curve(AUC)is0.654 0,followed by APWSn(1.336 3)with AUC=0.6342.The optimal predictor among all possible combinations for PBI was the combination of LA,PA,LP,WT,MPWS and MPWSn with prediction accuracy=1.414 6(AUC=0.715 8).LA was once again the best single predictor for PAI with the highest prediction accuracy(1.184 6)with AUC=0.606 4,followed by MPWSn(1. 183 2)with AUC=0.6084.The combination of PA,PB,WT,MPWS,MPWSn and APWSn gave the best prediction accuracy(1.302 5)for PAI,and the AUC value is 0.6657.PA was the best single predictor for WTI with highest prediction accuracy(1.288 7)with AUC=0.641 5,followed by WT(1.254 0),with AUC=0.6097.The combination of PA,PB,WT,LP,MinCT,MPWS and MPWS was the best predictor for WTI with prediction accuracy as 1.314 0,with AUC=0.6552.This indicated that PBI was a more predictable measure than WTI and PAI. The combinational predictors improved prediction accuracy by 9.95%,4.01%and 1.96%over the best single predictors for PAI,PBI and WTI(AUC values improved by9.78%,9.45%,and 2.14%),respectively.Conclusions The use of GLMM with 5-fold cross-validation strategy combining both morphological and biomechanical risk factors could potentially improve the accuracy of carotid plaque progression prediction.This study suggests that a linear combination of multiple predictors can provide potential improvement to existing plaque assessment schemes.
基金supported by the National Natural Science Foundation of China(32372247)the National Key Research and Development Program of China(2023YFF1104501)to Huiyuan Guo.
文摘Intestinal stem cells(ISCs)initiate intestinal epithelial regeneration and tumorigenesis,and they experi-ence rapid refilling upon various injuries for epithelial repair as well as tumor reoccurrence.It is crucial to reveal the mechanism underlying such plasticity for intestinal health.Recent studies have found that metabolic pathways control stem cell fate in homeostasis,but the role of metabolism in the regeneration of ISCs after damage has not been clarified.Here,we find that in a human colorectal cancer dataset,miR-29a and b(miR-29a/b)are metabolic regulators highly associated with intestinal tumorigenesis and worse prognostic value of radiotherapy.We also show that these two microRNAs are required for intesti-nal stemness maintenance in mice,and their expression is induced in regenerated ISCs after irradiation injury,resulting in skewed ISC fate from differentiation towards self-renewal.This upregulation of miR-29a/b expression in ISCs leads to suppression of fatty acid oxidation(FAO)and depression of oxidative phosphorylation,which in turn controls the balance between self-renewal and differentiation of ISCs.Deletion of miR-29a/b prevents these effects and thus impairs ISC-mediated epithelial recovery.Finally,we filter the potential targets of miR-29a/b and identify Hnf4g,a transcription factor,that drives this metabolic reprogramming through regulating FAO-related enzymes.Our work discovers an impor-tant metabolic mechanism of ISC-mediated regeneration and potentially pave the way for more targeted and effective therapeutic strategies for intestinal repair as well as tumor treatment.
基金the National Natural Science Foundation of China(81830035)the China Postdoctoral Science Foundation(2019M662290)。
文摘Potassium ions(K+),the pivotal cations for membrane potential,are particularly important for maintaining the physiological function of neurons[1].When the concentration of extracellular K+([K+]o)is pathologically changed,the intrinsic neuronal excitability and synaptic transmission are also altered,which have profound implications for many neurological disorders such as epilepsy,Parkinson's disease,and emotional disorders[2-4].
文摘Background:Esophageal cancer(ESCA)is a common digestive tract tumor.As a result,optimization of the early diagnosis of ESCA and identifying the contributing prognostic genes is urgently required.Herein,the prognosis of mitochondrial autophagy-related genes was analyzed in different subtypes of ESCA,and prognostic models were constructed to identify the immune cell infiltration with significant differences between subtypes.Methods:The Cancer Genome Atlas database was searched to download 185 ESCA samples,covering gene expression level data and clinical follow-up data,and 179 samples from the Gene Expression Omnibus database for subsequent validation analysis.The consensus Cluster Plus analysis method was employed to identify the best mitochondrial autophagy subtype.Kaplan-Meier curve was used to evaluate the correlation of survival prognosis between different subtype groups and actual survival prognostic information.A chi-square test was performed to analyze the correlation between subtypes and clinical information.Differential genetic analysis between different subtypes was performed using Limma packs(threshold setting:adj.p<0.05&|log2FC|>1).Univariate Cox regression analysis was applied to identifying genes with significant prognosis,and the LASSO algorithm screened out key genes.The risk scores were constructed by Stepwise Cox regression analysis and divided into high and low-risk groups.Independent prognostic factors were determined using the univariate and nomograms constructed by multivariate Cox analysis.The CIBERSORT method was used to calculate the composition ratio of 22 immune cells;the matrix and immune scores of tumor samples were calculated by the ESTIMATE algorithm.Wilcoxon’s test was performed to compare the expression differences of immune checkpoint genes and human leukocyte antigen family genes between high-and low-risk groups and the difference in IC50 between these risk groups of 138 chemotherapy drugs.Relationships between mitochondrial autophagy subtypes and high-and low-risk groups were assessed using the ggalluvial package in R3.6.1.Results:Seven mitochondrial autophagy genes associated with the of ESCA were identified(PTPN4,ALKBH4,IL6,FN3KRP,HSDL1,B3GNT2,CCT4).High and low risk were significantly correlated with the actual prognosis.Nomograms constructed by factors stage and Risk group showed significant relation with patient prognosis.Eleven immune cells significantly differing in the two subtypes were identified,followed by ten significantly different immune checkpoint genes.Conclusion:Seven mitochondrial autophagy genes associated with the prognosis of ESCA may serve as the key prognostic genes and novel therapeutic targets for esophageal cancer.
基金supported by China Postdoctoral Science Foundation,Grant 2024M753544Science and Technology Project of CSG,Grant GDKJXM2022106.
文摘Improving the computational efficiency of multi-physics simulation and constructing a real-time online simulation method is an important way to realise the virtual-real fusion of entities and data of power equipment with digital twin.In this paper,a datadriven fast calculation method for the temperature field of resin impregnated paper(RIP)bushing used in converter transformer valve-side is proposed,which combines the data dimensionality reduction technology and the surrogate model.After applying the finite element algorithm to obtain the temperature field distribution of RIP bushing under different operation conditions as the input dataset,the proper orthogonal decomposition(POD)algorithm is adopted to reduce the order and obtain the low-dimensional projection of the temperature data.On this basis,the surrogate model is used to construct the mapping relationship between the sensor monitoring data and the low-dimensional projection,so that it can achieve the fast calculation and reconstruction of temperature field distribution.The results show that this method can effectively and quickly calculate the overall temperature field distribution of the RIP bushing.The maximum relative error and the average relative error are less than 4.5%and 0.25%,respectively.The calculation speed is at the millisecond level,meeting the needs of digitalisation of power equipment.
基金supported by Science and Technology Project of State Grid Corporation of China,Grant/Award Number:SGLNDK00KJJS1900250.
文摘Resin impregnated paper(RIP)converter transformer valve-side bushings are the key equipment in converter stations.Local overheating of the RIP core not only reduces the transmission efficiency but also causes insulation failure of converter transformers.In this paper,a new heat dissipation structure is proposed to improve the temperature distribution homogeneity of the bushing using two-phase closed thermosyphon(TPCT).A test model is developed to determine the optimal working fluid inventory.Then,the temperature distribution of a±400-kV RIP converter transformer valve-side bushing with an optimised heat dissipation structure is obtained using the coupled three-dimensional electromagnetic-fluid-thermal numerical simulation method considering multiphase flow and phase change processes.The influence of the new structure on the electric field is analysed.The simulation result is verified by the temperature rise test.The results show that two-phase closed thermosyphon can reduce the maximum temperature of the RIP valve-side bushings and significantly improve the temperature distribution homogeneity.
基金sponsored by the research programs of the National Social Science Foundation of China (Grant No.22BSH086)the research program of the Center for Chinese Urbanization Studies of Soochow University,Collaborative Innovation Center for New Urbanization and Social Governance of universities in Jiangsu (Grant No. 22CZHC012)+1 种基金Chinese National Architecture Research Association (Grant No. NAIC202425)the Key funded Project of the High Quality Project of Social Science Applied Research in Jiangsu Province in 2024 (Grant No. 24SYA-005)
文摘Rapid urbanization in China presents complex challenges for urban development,particularly in older neighborhoods.The rise of digital cities and the shift from expansion to optimizing existing urban areas have highlighted significant issues related to infrastructure,regeneration,and the preservation of local characteristics.These challenges hinder sustainable urban development and negatively impact residents’quality of life,making the transition to smart cities imperative.This study uses Suzhou’s old neighborhoods as a case study,employing big data and Geographic Information System(GIS)software to conduct a comprehensive quantitative assessment.Techniques such as kernel density and accessibility analysis reveal key issues in infrastructure,sustainability,and local characteristics,providing a data foundation for targeted strategies.Based on these findings,the paper proposes micro-renovation strategies aimed at enhancing community functionality and improving residents’quality of life through refined management.The study underscores that,under the“ecological+digital”sustainable development framework,renewing old neighborhoods can address existing challenges while revitalizing cities towards smarter,greener,and more livable futures.
基金supported by the National Natural Science Foundation of China(62375081,U22A20138,52372146,62090035,52221001,and 52402181)the National Key R&D Program of China(2022YFA1204300 and 2022YFA1402501).
文摘Flexible photodetector(PD)arrays have the potential to replace the rods and cones in the retina,converting external light signals into electrical signals and offering hope for blind patients to regain vision.However,issues like discontinuous electrode surfaces and incompletely crystallized perovskites can cause cracks and degrade the performance of flexible PDs during repeated bending,hindering their development and applications.In this study,we employ a combination of radio frequency magnetron sputtering and angular ion beam polishing to achieve an ultrathin,ultrasmooth platinum(Pt)electrode film(UTPF)with a thickness of less than 10 nm.Building on this,a vapor deposition method with dynamically regulated evaporation rates is developed to obtain a dense-gradient PbI_(2)precursor.This funnel-shaped vertical structure precursor facilitates the penetration of CH_(3)NH_(3)I solution,ultimately resulting in a dense and uniform perovskite film with large grains and strong interfacial bonding with UTPF.The results indicate that the flexible PD arrays exhibit excellent optoelectronic performances,characterized by high sensitivity,detectivity and a large on/off current ratio.Furthermore,benefitting from their exceptional flexibility and electrical stability,the devices retain 92.53%of the original photocurrent after 4000 bending cycles at large angles.Notably,the integrated 10×10 flexible PD arrays demonstrate good uniformity in dark current and photocurrent,along with high imaging resolution,showing the reliable imaging capabilities of the flexible arrays and their potential applications in artificial retina.
基金Shanghai Henlius Biotech Inc.NationalNatural Science Foundation of China,Grant/Award Number:82473000。
文摘Background:The ASTRUM-005 study previously demonstrated a signifi-cant overall survival(OS)benefit with serplulimab(a programmed death1 inhibitor)plus chemotherapy versus chemotherapy alone in previouslyuntreated extensive-stage small-cell lung cancer(ES-SCLC).Here,we reportupdated efficacy and safety results after an extended median follow-up of 19.8months,along with the first report on findings from exploratory biomarkeranalyses.Methods:A total of 585 patients were randomized in a 2:1 ratio to receive4.5 mg/kg serplulimab(n=389)or placebo(n=196)intravenously every 3weeks,together with carboplatin and etoposide.The primary endpoint was OS.In addition,genomic profiling was performed to identify mutated genes,and quantitative serum proteome profiling was conducted to identify differ-entially expressed proteins(DEPs)between responders and non-responders ofserplulimab plus chemotherapy.Regression analysis was subsequently used toconstruct a protein signature based on the DEPs.The associations betweenefficacy outcomes(objective response rate[ORR],OS,and progression-free sur-vival[PFS])and gene mutation status or DEP expression were also examinedwith regression analysis.Furthermore,the prognostic value of hematologicalparameters was evaluated.Results:In the intent-to-treat population,the median OS was 15.8 monthsin the serplulimab group versus 11.1 months in the placebo group(haz-ard ratio,0.62;95%confidence interval,0.50-0.76;P<0.001).We identified181 DEPs between responders and non-responders in the serplulimab group,from which a 15-protein signature was constructed.In the serplulimab group,patients with a higher 15-protein signature score were associated with sig-nificantly longer OS and PFS.Also,patients harboring tumor-suppressorretinoblastoma-1(RB1)mutations or mutations in Notch pathway membersshowed improved ORR,OS,or PFS compared with their wild-type counter-parts.Baseline neutrophil-to-lymphocyte ratio(NLR)and lactate dehydrogenase(LDH)level were independent prognosticators of patients with ES-SCLC.Conclusions:First-line serplulimab provided a sustained clinical benefit overplacebo in patients with ES-SCLC.A 15-protein signature and mutations in RB1or Notch pathway genes may serve as predictive biomarkers for benefits fromserplulimab plus chemotherapy,while baseline NLR and LDH were independentprognosticators for ES-SCLC.
基金support by the National Natural Science Foundation of China(12222508,12475325,and 22209061)the Youth Innovation Promotion Association CAS(2020454)+2 种基金the National Key R&D Program of China(2019YFA0405601 and2023YFA1506304)the Fundamental Research Funds for the Universities of Inner Mongolia Autonomous Region(JY20250030)the Start-up Fund for Senior Talents in Jiangsu University(21JDG060)。
文摘Photocatalytic urea production from nitrogen(N_(2))and carbon dioxide(CO_(2))is a sustainable and ecofriendly alternative to the Bosch-Meiser route.However,it remains a significant challenge in developing highly efficient photocatalysts for enhancing C-N coupling to high-yield urea synthesis.Herein,we propose a multi-site photocatalyst concept to address the concern of low yield by simultaneously improving photogenerated carrier separation and reactant activation.As a proof of concept,a well-defined multisite photocatalyst,Ru nanoparticles and Cu single atoms decorated CeO_(2)nanorods(Ru-Cu/CeO_(2)),is developed for efficient urea production.The incorporation of Ru and Cu sites is crucial not only to generate high-density photogenerated electrons,but also to facilitate N_(2)and CO_(2)adsorption and conversion.The in situ formed local nitrogen-rich area at Ru sites increases the encounter possibility with the carbon-containing species generated from Cu sites,substantially promoting C-N coupling.The Ru-Cu/CeO_(2)photocatalyst exhibits an impressive urea yield rate of 16.7μmol g^(-1)h^(-1),which ranks among the best performance reported to date.This work emphasizes the importance of multi-site catalyst design concept in guaranteeing rapid C-N coupling in photocatalytic urea synthesis and beyond.
基金the Zhejiang Provincial Natural Science Foundation of China(No.LY23H180001)the Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,the China Institute of Water Resources and Hydropower Research(No.IWHR-SKL-201905)the National Natural Science Foundation of China(No.11701363).
文摘Water quality prediction is vital for solving water pollution and protecting the water environment.In terms of the characteristics of nonlinearity,instability,and randomness of water quality parameters,a short-term water quality prediction model was proposed based on variational mode decomposition(VMD)and improved grasshopper optimization algorithm(IGOA),so as to optimize long short-term memory neural network(LSTM).First,VMD was adopted to decompose the water quality data into a series of relatively stable components,with the aim to reduce the instability of the original data and increase the predictability,then each component was input into the iGOA-LSTM model for prediction.Finally,each component was added to obtain the predicted values.In this study,the monitoring data from Dayangzhou Station and Shengmi Station of the Ganjiang River was used for training and prediction.The experimental results showed that the prediction accuracy of the VMDIGOA-LSTM model proposed was higher than that of the integrated model of Ensemble Empirical Mode Decomposition(EEMD),the integrated model of Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN),Nonlinear Autoregressive Network with Exogenous Inputs(NARX),Recurrent Neural Network(RNN),as well as other models,showing better performance in short-term prediction.The current study will provide a reliable solution for water quality prediction studies in other areas.
基金the science and technology project of State Grid Corporation of China(SGLNDK00KJJS1900250)the Fundamental Research Funds for the Central Universities(xzy012019029).
文摘Gas-filled internal crack might appear in thermoset materials like epoxy resin during the equipment manufacturing,which would become a vulnerable local region to initiate the electrical tree,thus prone to cause insulation failure.The withstand voltage test was carried on epoxy samples with artificial cracks based on a rod-plane electrode arrange-ment.Simultaneously,surface state variation and tree evolution with crack were observed by an optical microscope in conjunction with a charge-coupled device camera.The changes in morphology and chemical status of the crack surface were characterized by scanning electron microscopy,laser Raman spectrometer and energy dispersive spec-trometer,respectively.It was found that the erosion and tree started from the borderline of crack under a relatively low electric field strength;however,the area near the electrode had relatively little damage.The breaking of epoxy molecular chains coarsens the crack surface and further forms deep channels on a micro-level,which is the forerunner of the electrical tree inception.Based on these,the initiation mechanisms of the crack-induced electrical tree and the reasons for the erosion near the borderline have been revealed.This study provides a train thought for the polymer degradation opening up into the initial tree channel during tree evolution processes.
基金National Natural Science Foundation of China,Grant/Award Number:52107163。
文摘A wireless signal transmission technology based on acoustic carrier is proposed,which overcomes the limitation of electromagnetic signal shielding and shows great potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear(GIS)/gasinsulated transmission line(GIL).Here,the state parameter of the sliding electrical contact is modulated onto the frequency domain of an ultrasound wave.As a mechanical wave,the ultrasonic wave is immune to electromagnetic shielding,so that it could carry the sensing signal to penetrate the metal shielding layer and transmit to the external terminals of GIS/GIL.The principle and signal modulation process of the acoustic carrier based transmission system have been demonstrated in detail.Both simulation and experiment have been conducted to analyse the system characteristics as well as optimise the system configuration.As a proof-of-concept application,the in situ and on-line monitoring of the thermal rise of a slide electrical contact both in a current loading equivalent model and a prototype of GIS is demonstrated.Experimental results fit well with the physical process,and show a good measurement accuracy of 0.6%and tem-perature sensitivity of 400 Hz/℃.
