The real-time monitoring of fracture propagation during hydraulic fracturing is crucial for obtaining a deeper understanding of fracture morphology and optimizing hydraulic fracture designs.Accurate measurements of ke...The real-time monitoring of fracture propagation during hydraulic fracturing is crucial for obtaining a deeper understanding of fracture morphology and optimizing hydraulic fracture designs.Accurate measurements of key fracture parameters,such as the fracture height and width,are particularly important to ensure efficient oilfield development and precise fracture diagnosis.This study utilized the optical frequency domain reflectometer(OFDR)technique in physical simulation experiments to monitor fractures during indoor true triaxial hydraulic fracturing experiments.The results indicate that the distributed fiber optic strain monitoring technology can efficiently capture the initiation and expansion of fractures.In horizontal well monitoring,the fiber strain waterfall plot can be used to interpret the fracture width,initiation location,and expansion speed.The fiber response can be divided into three stages:strain contraction convergence,strain band formation,and postshutdown strain rate reversal.When the fracture does not contact the fiber,a dual peak strain phenomenon occurs in the fiber and gradually converges as the fracture approaches.During vertical well monitoring in adjacent wells,within the effective monitoring range of the fiber,the axial strain produced by the fiber can represent the fracture height with an accuracy of 95.6%relative to the actual fracture height.This study provides a new perspective on real-time fracture monitoring.The response patterns of fiber-induced strain due to fractures can help us better understand and assess the dynamic fracture behavior,offering significant value for the optimization of oilfield development and fracture diagnostic techniques.展开更多
Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through mic...Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through microbiome modulation,their therapeutic impact on gut dysfunction-induced bone and muscle loss remains to be elucidated.Employing dextran sulfate sodium(DSS)-induced gut dysfunction model and wide-spectrum antibiotics(ABX)-treated mice model,our study revealed that gut dysfunction instigates muscle and bone loss,accompanied by microbial imbalances.Importantly,Bifidobacterium animalis subsp.lactis A6(B.lactis A6)administration significantly ameliorated muscle and bone loss by modulating gut microbiota composition and enhancing butyrate-producing bacteria.This intervention effectively restored depleted butyrate levels in serum,muscle,and bone tissues caused by gut dysfunction.Furthermore,butyrate supplementation mitigated musculoskeletal loss by repairing the damaged intestinal barrier and enriching beneficial butyrate-producing bacteria.Importantly,butyrate inhibited the NF-κB pathway activation,and reduced the secretion of corresponding inflammatory factors in T cells.Our study highlights the critical role of dysbiosis in gut dysfunction-induced musculoskeletal loss and underscores the therapeutic potential of B.lactis A6.These discoveries offer new microbiome directions for translational and clinical research,providing promising strategies for preventing and managing musculoskeletal diseases.展开更多
The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonizatio...The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonization.However,steelwork off-gases typically contain various impurities,including H_(2)S,which can deactivate commercial methanol synthesis catalysts,Cu/ZnO/Al_(2)O_(3)(CZA).Reverse water-gas shift(RWGS)reaction is the predominant side reaction in CO_(2) hydrogenation to methanol which can occur at ambient pressure,enabling the decouple of RWGS from methanol production at high pressure.Then,a series of activated CZA catalysts has been in-situ pretreated in 400 ppm H_(2)S/Ar at 250℃and tested for both RWGS reaction at ambient pressure and CO_(2) hydrogenation to methanol at high pressure.An innovative decoupling strategy was employed to isolate the RWGS reaction from the methanol synthesis process,enabling the investigation of the evolution of active site structures and the poisoning mechanism through elemental analysis,X-ray Diffraction,X-ray Photoelectron Spectroscopy,Fourier Transform Infrared Spectroscopy,Temperature Programmed Reduction and CO_(2) Temperature Programmed Desorption.The results indicate that there are different dynamic migration behaviors of ZnO_(x) in the two reaction systems,leading to different poisoning mechanisms.These interesting findings are beneficial to develop sulfur resistant and durable highly efficient catalysts for CO_(2) hydrogenation to methanol,promoting the carbon emission reduction in steel industry.展开更多
Elucidating the microbial mechanisms that trigger Fusarium wilt represents a key step in addressing the barriers to sustainable cropping.However,from the perspective of the complete microbiome,the integrated role of s...Elucidating the microbial mechanisms that trigger Fusarium wilt represents a key step in addressing the barriers to sustainable cropping.However,from the perspective of the complete microbiome,the integrated role of soil nutrients and microbial community in the fields with different rates of wilt disease remains unclear.In this study,we examined the potential interrelationships among the nutrients,bacteria,fungi,and protists in rhizospheric soils collected from the fields with watermelon cropping for 7 years at the Zhuanghang Experimental Station of Shanghai Academy of Agricultural Sciences,China.The soils collected were characterized by a high(HW,81.25%)or low(LW,6.25%)wilting rate.The HW soil was found to contain a higher abundance of Fusarium oxysporum(1.30-fold higher)than the LW soil,along with higher contents of available phosphorus(1.31-fold higher)and available potassium(2.39-fold higher).In addition,the interkingdom correlation between protists and bacteria in the HW soil was 2.08-fold higher than that in the LW soil.Furthermore,structural equation modeling revealed that an excess of soil available potassium enhanced the predation by potentially detrimental phagotrophic protists on potentially beneficial bacteria.In summary,our findings indicated that a balanced nutrient input and the interactions between protists(Cercomonas and Colpoda)and beneficial bacteria(Bacillus)played important roles in controlling the incidence of watermelon Fusarium wilt.展开更多
Efficient,safe,and economical hydrogen storage technology is vital for hydrogen’s broad use as an energy carrier,with V-based BCC alloys standing out for their high theoretical storage capacity.However,the high cost ...Efficient,safe,and economical hydrogen storage technology is vital for hydrogen’s broad use as an energy carrier,with V-based BCC alloys standing out for their high theoretical storage capacity.However,the high cost of V has restricted their practical application.In this work,a cost-effective Ti–Cr–(Fe V80)alloy was successfully synthesized through a pre-refinement process involving the addition of Y/Zr to the Fe V80 alloy.The resulting Ti_(27)Cr_(27)(Fe V80+Y)_(46)alloy exhibited an effective dehydriding capacity of 2.3 wt%,with a capacity retention rate of 97.2%after 200 cycles.Through the analysis of HSC Chemistry 6.0 software and backscattered electron(BSE),it has been discovered that the prerefinement process significantly reduces the presence of Al,Si,and O impurities,leading to improved compositional uniformity.After the re-refinement,the formation of the Ti–rich phases had been notably curbed.This,along with a marked decrease in the pressure–composition–temperature(PCT)curve’s slope factor from 1.58 to 0.36,results in enhanced hydriding capacity(from 3.2 wt%to 3.7 wt%),reversible dehydriding capacity(from 2.0 wt%to 2.3 wt%),and a remarkable increase in the capacity retention rate(from 75.8%to 97.2%).The kinetics and thermodynamic properties of the alloys were calculated using the Arrhenius and Van’t Hoff equations,providing insights into their performance characteristics.The mechanism behind the alloy’s improved cyclic stability has been elucidated through an analysis of lattice distortion and X-ray photoelectron spectroscopy(XPS).These findings open new routes for the development of cost-effective Fe V80-based hydrogen storage materials.展开更多
The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)conta...The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)contamination on the gas diffusion layer(GDL)and PEMFC performance,systematically analyzing the physicochemical property changes and their correlation with electrochemical performance.The results indicate that after post-treatment,the GDL surface exhibited exposed carbon fibers,cracks,and large pores in the microporous layer(MPL),with a noticeable detachment of PTFE.There was a marked reduction in C and F element signals,an increase in O element signals,deposition of Cr_(2)(SO_(4))_(3),formation of C=O and C=C bonds,appearance of Cr_(2)(SO_(4))_(3)characteristic peaks,and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology,structure,and chemical composition.The decline in mechanical strength and thermal stability,and increased surface roughness and resistance negatively impacted fuel cell performance.At high current densities,the emergence of water flooding increased mass transfer resistance from 0.1Ωcm^(2)to 1.968Ωcm^(2),with a maximum power density decay rate reaching 71.17%.This study reveals the significant negative impact of Cr_(2)(SO_(4))_(3)contamination on GDL and fuel cell performance,highlighting that changes in surface structure,reduced hydrophobicity,and increased mass transfer resistance are primary causes of performance degradation.The findings provide crucial insights for improving GDL materials,optimizing fuel cell manufacturing and operation processes,and addressing contamination issues in practical applications.展开更多
Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were succ...Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were successfully synthesized by hydrothermal,annealing and phosphating methods on nickel foam(NF).The unusual shape of the sea urchin facilitates gas release and mass transfer and increases the interaction between catalysts and electrolytes.The Ni_(4)Mo/NF and Ni-Mo-P/NF electrodes only need overpotentials of 72 and 197 mV to reach 50 mA·cm^(−2) under alkaline conditions for hydrogen evolution reaction and oxygen evolution reaction,respectively.The Ni_(4)Mo/NF and Ni-Mo-P/NF asymmetric electrodes were used as anode and cathode for the overall water splitting,respectively.In 1.0 M KOH,at a voltage of 1.485 V,the electrolytic device generated 50 mA·cm^(−2) current density,maintaining for 24 h without reduction.The labor presents a simple method to synthesize a highly active,low-cost,and strongly durable self-supporting electrode for over-water splitting.展开更多
The metal-carbon dioxide batteries,emerging as high-energy-density energy storage devices,enable direct CO_(2)utilization,offering promising prospects for CO_(2)capture and utilization,energy conversion,and storage.Ho...The metal-carbon dioxide batteries,emerging as high-energy-density energy storage devices,enable direct CO_(2)utilization,offering promising prospects for CO_(2)capture and utilization,energy conversion,and storage.However,the electrochemical performance of M-CO_(2)batteries faces significant challenges,particularly at extreme temperatures.Issues such as high overpotential,poor charge reversibility,and cycling capacity decay arise from complex reaction interfaces,sluggish oxidation kinetics,inefficient catalysts,dendrite growth,and unstable electrolytes.Despite significant advancements at room temperature,limited research has focused on the performance of M-CO_(2)batteries across a wide-temperature range.This review examines the effects of low and high temperatures on M-CO_(2)battery components and their reaction mechanism,as well as the advancements made in extending operational ranges from room temperature to extremely low and high temperatures.It discusses strategies to enhance electrochemical performance at extreme temperatures and outlines opportunities,challenges,and future directions for the development of M-CO_(2)batteries.展开更多
The deep seabed is known for its abundant reserves of various mineral resources.Notably,the Clarion Clipperton(C-C)mining area in the northeast Pacific Ocean,where China holds exploration rights,is particularly rich i...The deep seabed is known for its abundant reserves of various mineral resources.Notably,the Clarion Clipperton(C-C)mining area in the northeast Pacific Ocean,where China holds exploration rights,is particularly rich in deep-sea polymetallic nodules.These nodules,which are nodular and unevenly distributed in seafloor sediments,have significant industrial exploitation value.Over the decades,the deep-sea mining industry has increasingly adopted systems that combine rigid and flexible risers supported by large surface mining vessels.However,current systems face economic and structural stability challenges,hindering the development of deep-sea mining technology.This paper proposes a new structural design for a deep-sea mining system based on flexible risers,validated through numerical simulations and experimental research.The system composition,function and operational characteristics are comprehensively introduced.Detailed calculations determine the production capacity of the deep-sea mining system and the dimensions of the seabed mining subsystem.Finite element numerical simulations analyze the morphological changes of flexible risers and the stress conditions at key connection points under different ocean current incident angles.Experimental research verifies the feasibility of collaborative movement between two tethered underwater devices.The proposed deep-sea mining system,utilizing flexible risers,significantly advances the establishment of a commercial deep-sea mining system.The production calculations and parameter determinations provide essential references for the system’s future detailed design.Furthermore,the finite element simulation model established in this paper provides a research basis,and the method established in this paper offers a foundation for subsequent research under more complex ocean conditions.The control strategy for the collaborative movement between two tethered underwater devices provides an effective solution for deep-sea mining control systems.展开更多
BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,...BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,which caused a marked increase in surgical difficulty and risk compared to treatment for typical choledocholithiasis.This phenomenon has not been described in previous studies.AIM To propose the ice-breaking sign and evaluate its influence on treatment strategies for choledocholithiasis.METHODS Using a retrospective case-control study design,patients who were diagnosed with common bile duct stones and admitted to the Emergency Department of Peking University Third Hospital between January 2018 and December 2023 were included.Propensity score matching was used to match cases and controls.Univariate analysis was conducted to assess the differences in clinical data between the two groups of patients.RESULTS There were no significant differences in the baseline data between the two groups,except for higher incidence of jaundice,alkaline phosphatase and total bilirubin in the ice-breaking sign group.Compared to the control group,the ice-breaking sign group had lower success rates for endoscopic retrograde cholangiopancreatography(25.0%vs 81.8%,P=0.006)and laparoscopic common bile duct exploration(69.4%vs 93.8%,P=0.007),longer operation time(148.04±60.55 minutes vs 106.15±35.21 minutes,P=0.001),higher likelihood of T-tube placement(62.2%vs 31.3%,P=0.016)and using lithotripsy techniques during surgery(29.7%vs 0%,P=0.001),more intraoperative bleeding[25.0(20.0-50.0)mL vs 10.0(10.0-20.0)mL,P<0.001]and longer postoperative hospital stay[6.50(5.0-9.0)days vs 5.50(3.0-6.50)days,P=0.002].The ice-breaking sign group showed significantly more dilatation in the proximal than distal bile duct.CONCLUSION The ice-breaking sign,a newly identified radiological phenomenon,may influence therapeutic decisions in choledocholithiasis,suggesting laparoscopic common bile duct exploration as the preferred approach over endoscopic retrograde cholangiopancreatography in patients exhibiting this sign.展开更多
Aqueous Cu-S batteries(ACSBs)offer a promising energy storage solution by leveraging the unique redox properties of Cu^(2+)ions,enabling high theoretical capacities through a four-electron transfer reaction.These adva...Aqueous Cu-S batteries(ACSBs)offer a promising energy storage solution by leveraging the unique redox properties of Cu^(2+)ions,enabling high theoretical capacities through a four-electron transfer reaction.These advantages are coupled with inherent safety and low cost,making ACSBs a compelling alternative to traditional batteries.However,the practical application of ACSBs is hindered by the low conductivity of sulfur and the high energy barrier associated with phase transitions,which limit material utilization and reaction kinetics.Herein,we propose for the first time a multifunctional organic small-molecule polysulfide catalyst,Zn(phen)S_(6),and successfully convert them into nanocapsules that are homogeneously dispersed on the cathode surface,effectively increasing the catalytic active sites.Moreover,this complex undergoes reversible reactions during cycling,releasing zinc ions that form a dense protective layer on the anode during charging,effectively inhibiting dendrite growth.Meanwhile,Zn(phen)S_(6)interacts with Cu^(2+)ions to undergo an in-situ solid-state transformation into a novel catalyst,[Cu(phen)(H_(2)O)_(2)SO_(4)]_(n).This catalyst not only accelerates electron transfer but also serves as an ion transport channel,significantly boosting reaction kinetics.This battery demonstrates exceptional stability,retaining 97.7%of its initial capacity after 1200 cycles at a high current density of 10 A g^(-1).Furthermore,it maintains an impressive capacity of 1157 m Ah g^(-1)after 1600 cycles at 20 A g^(-1).This work provides pivotal insights into the design and application of molecular catalysts,opening new pathways for advancing Cu-S battery technologies.展开更多
Objective:To elucidate the specific mechanisms by which electroacupuncture(EA)alleviates anxiety and fear behaviors associated with posttraumatic stress disorder(PTSD),focusing on the role of lipocalin-2(Lcn2).Methods...Objective:To elucidate the specific mechanisms by which electroacupuncture(EA)alleviates anxiety and fear behaviors associated with posttraumatic stress disorder(PTSD),focusing on the role of lipocalin-2(Lcn2).Methods:The PTSD mouse model was subjected to single prolonged stress and shock(SPS&S),and the animals received 15 min sessions of EA at Shenmen acupoint(HT7).Behavioral tests were used to investigate the effects of EA at HT7 on anxiety and fear.Western blotting and enzyme-linked immunosorbent assay were used to quantify Lcn2 and inflammatory cytokine levels in the prefrontal cortex(PFC).Additionally,the activity of PFC neurons was evaluated by immunofluorescence and in vivo electrophysiology.Results:Mice subjected to SPS&S presented increased anxiety-and fear-like behaviors.Lcn2 expression in the PFC was significantly upregulated following SPS&S,leading to increased expression of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 and suppression of PFC neuronal activity.However,EA at HT7 inhibited Lcn2 release,reducing neuroinflammation and hypoexcitability in the PFC.Lcn2 overexpression mitigated the effects of EA at HT7,resulting in anxiety-and fear-like behaviors.Conclusion:EA at HT7 can ameliorate PTSD-associated anxiety and fear,and its mechanism of action appears to involve the inhibition of Lcn2-mediated neural activity and inflammation in the PFC.展开更多
Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides ne...Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides new approaches to enhance hydrate development effectiveness.Addressing the current lack of quantitative and objective methods for evaluating the fracability of hydrate reservoirs,this study clarifies the relationship between geological and engineering fracability and proposes a comprehensive evaluation model for hydrate reservoir fracability based on grey relational analysis and the criteria importance through intercriteria correlation method.By integrating results from hydraulic fracturing experiments on hydrate sediments,the fracability of hydrate reservoirs is assessed.The concept of critical construction parameter curves for hydrate reservoirs is introduced for the first time.Additionally,two-dimensional fracability index evaluation charts and three-dimensional fracability construction condition discrimination charts are established.The results indicate that as the comprehensive fracability index increases,the feasibility of forming fractures in hydrate reservoirs improves,and the required normalized fracturing construction parameters gradually decrease.The accuracy rate of the charts in judging experimental results reached 89.74%,enabling quick evaluations of whether hydrate reservoirs are worth fracturing,easy to fracture,and capable of being fractured.This has significant engineering implications forthehydraulicfracturingof hydratereservoirs.展开更多
This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regr...This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regression.Taking City Commercial Bank A as an instance,the model identifies 12.3%redundant positions and matches jobs with business scale.Additionally,the study proposes a“staffing effectiveness salary”system,providing a framework for optimizing commercial bank human capital in the digital age.展开更多
The Suizhou meteorite is a heavily shock-met-amorphosed L6 chondrite which contains thin shock melt veins.So far,26 high-pressure phases have been identified from the meteorite.Among the high-pressure phases,ten of th...The Suizhou meteorite is a heavily shock-met-amorphosed L6 chondrite which contains thin shock melt veins.So far,26 high-pressure phases have been identified from the meteorite.Among the high-pressure phases,ten of them were approved as new minerals which include tuite,xieite,wangdaodeite,chenmingite,hemleyite,poirierite,asimowite,hiroseite,elgoresyite,and ohtaniite,by the Commission on New Minerals,Nomenclature and Classification of the International Mineralogical Association.Other high-pressure phases identified from the meteorite are ahrensite,akimotoite,bridgmanite,lingunite,magnesiowüstite,majorite,majorite-pyrope_(ss),maskelynite,riesite,ringwoodite,wadsleyite,and 5 other phases including phase A,vitrified phase B and phase C,phase D(Ca-rich majorite),and partly inverted ringwoodite.The occurrence and abundance of high-pressure phases makes this meteorite the one with the richest variety of high-pressure minerals to date.展开更多
Hydraulic fracturing is a key technology for the efficient development of deep oil and gas reservoirs.However,fracture propagation behavior is influenced by rock elastoplasticity and thermal stress,making it difficult...Hydraulic fracturing is a key technology for the efficient development of deep oil and gas reservoirs.However,fracture propagation behavior is influenced by rock elastoplasticity and thermal stress,making it difficult for traditional linear elastic models to accurately describe its dynamic response.To address this,this study employs the Continuum-Discontinuum Element Method(CDEM),incorporating an elastoplastic constitutive model,thermo-hydro-mechanical(THM)coupling effects,and cohesive zone characteristics at the fracture tip to establish a numerical model for hydraulic fracture propagation in deep elastoplastic reservoirs.A systematic investigation was conducted into the effects of fluid viscosity,reservoir temperature,injection rate,elastic modulus,and horizontal stress difference on fracture propagation.The findings show that a larger horizontal stress differential results in a more rectangular fracture geometry,a shorter fracture length,and a wider fracture.An increase in elastic modulus has a negligible impact on fracture length but reduces fracture width,resulting in a rounded rectangular morphology.Elevated reservoir temperature induces thermal tensile stress around the fracture,mitigating in-situ stress effects and reducing both breakdown and propagation pressures.Higher injection rates and fluid viscosity increase fracture initiation difficulty,promoting shorter but wider fractures with enhanced height growth beyond interlayer barriers.Additionally,horizontal stress significantly affects near-fracture plastic deformation:when the stress difference increases from 10 to 25 MPa,the maximum cumulative plastic strain in the surrounding rock rises by 66.67%.By integrating elastoplasticity and thermal stress effects,this study overcomes the limitations of conventional hydraulic fracturing simulations,offering novel insights for optimizing extraction strategies in deep unconventional reservoirs.展开更多
EMC anechoic chamber is used for radiation emission and radiation immunity test,and the wireless performance of products needs to be tested in OTA anechoic chamber.With more and more electronic and electrical equipmen...EMC anechoic chamber is used for radiation emission and radiation immunity test,and the wireless performance of products needs to be tested in OTA anechoic chamber.With more and more electronic and electrical equipment with wireless communication function,the rapid construction of a compatible OTA test system in the existing EMC anechoic chamber can save the cost and space of enterprises and third-party laboratories that already have EMC anechoic chamber.In this paper,the OTA test system is built in the existing EMC anechoic room,the ripple calibration test is carried out according to the OTA standard,the TRP and TIS tests are carried out on two test samples with different wireless communication standards,and the test samples are taken to the OTA anechoic room for a comparison test.The comparison between the ripple calibration data and the OTA test data showed that the EMC anechoic chamber could perform OTA test without affecting the original test ability.The data results provide a basis for the implementation of EMC anechoic chamber compatibility upgrade OTA test,and provide reference for further optimization of the compatible test system,reduction of test differences,and the design of anechoic chamber integrating two test functions.展开更多
Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free m...Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free method by a complexmediated nucleophilic aromatic substitution of aryl nitriles with amines.The method can lead to rich D-A type aggregation-induced emission luminogens(AIEgens)with tunable properties.They emit from deep-blue to yellow-green and possess high photoluminescence quantum yields up to 70.5%in the aggregate state.Interestingly,the suppression of intramolecular flapping is proved to play an indispensable role in the AIE behavior,which is different from the mechanism met in other AIEgens.Moreover,the biocompatible AIEgens possess specific staining of lipid droplets in HeLa cells and the superiority of identifying fatty liver over traditional Oil Red O staining is exhibited.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52104060)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2021QE015).
文摘The real-time monitoring of fracture propagation during hydraulic fracturing is crucial for obtaining a deeper understanding of fracture morphology and optimizing hydraulic fracture designs.Accurate measurements of key fracture parameters,such as the fracture height and width,are particularly important to ensure efficient oilfield development and precise fracture diagnosis.This study utilized the optical frequency domain reflectometer(OFDR)technique in physical simulation experiments to monitor fractures during indoor true triaxial hydraulic fracturing experiments.The results indicate that the distributed fiber optic strain monitoring technology can efficiently capture the initiation and expansion of fractures.In horizontal well monitoring,the fiber strain waterfall plot can be used to interpret the fracture width,initiation location,and expansion speed.The fiber response can be divided into three stages:strain contraction convergence,strain band formation,and postshutdown strain rate reversal.When the fracture does not contact the fiber,a dual peak strain phenomenon occurs in the fiber and gradually converges as the fracture approaches.During vertical well monitoring in adjacent wells,within the effective monitoring range of the fiber,the axial strain produced by the fiber can represent the fracture height with an accuracy of 95.6%relative to the actual fracture height.This study provides a new perspective on real-time fracture monitoring.The response patterns of fiber-induced strain due to fractures can help us better understand and assess the dynamic fracture behavior,offering significant value for the optimization of oilfield development and fracture diagnostic techniques.
基金supported by funding from the National Natural Science Foundation of China(82272478,82002330,82202728)the National Key R&D Program of China(No.2022YFF1100100)the Natural Science Foundation of Beijing(L222086).
文摘Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through microbiome modulation,their therapeutic impact on gut dysfunction-induced bone and muscle loss remains to be elucidated.Employing dextran sulfate sodium(DSS)-induced gut dysfunction model and wide-spectrum antibiotics(ABX)-treated mice model,our study revealed that gut dysfunction instigates muscle and bone loss,accompanied by microbial imbalances.Importantly,Bifidobacterium animalis subsp.lactis A6(B.lactis A6)administration significantly ameliorated muscle and bone loss by modulating gut microbiota composition and enhancing butyrate-producing bacteria.This intervention effectively restored depleted butyrate levels in serum,muscle,and bone tissues caused by gut dysfunction.Furthermore,butyrate supplementation mitigated musculoskeletal loss by repairing the damaged intestinal barrier and enriching beneficial butyrate-producing bacteria.Importantly,butyrate inhibited the NF-κB pathway activation,and reduced the secretion of corresponding inflammatory factors in T cells.Our study highlights the critical role of dysbiosis in gut dysfunction-induced musculoskeletal loss and underscores the therapeutic potential of B.lactis A6.These discoveries offer new microbiome directions for translational and clinical research,providing promising strategies for preventing and managing musculoskeletal diseases.
基金supported by the National Natural Science Foundation of China(Nos.22276060 and 21976059)Guangdong Basic and Applied Basic Research Foundation(No.2024A1515012636)China Scholarship Council Scholarship(No.201906155006)。
文摘The reduction of carbon emissions in the steel industry is a significant challenge,and utilizing CO_(2) from carbon intensive steel industry off-gases for methanol production is a promising strategy for decarbonization.However,steelwork off-gases typically contain various impurities,including H_(2)S,which can deactivate commercial methanol synthesis catalysts,Cu/ZnO/Al_(2)O_(3)(CZA).Reverse water-gas shift(RWGS)reaction is the predominant side reaction in CO_(2) hydrogenation to methanol which can occur at ambient pressure,enabling the decouple of RWGS from methanol production at high pressure.Then,a series of activated CZA catalysts has been in-situ pretreated in 400 ppm H_(2)S/Ar at 250℃and tested for both RWGS reaction at ambient pressure and CO_(2) hydrogenation to methanol at high pressure.An innovative decoupling strategy was employed to isolate the RWGS reaction from the methanol synthesis process,enabling the investigation of the evolution of active site structures and the poisoning mechanism through elemental analysis,X-ray Diffraction,X-ray Photoelectron Spectroscopy,Fourier Transform Infrared Spectroscopy,Temperature Programmed Reduction and CO_(2) Temperature Programmed Desorption.The results indicate that there are different dynamic migration behaviors of ZnO_(x) in the two reaction systems,leading to different poisoning mechanisms.These interesting findings are beneficial to develop sulfur resistant and durable highly efficient catalysts for CO_(2) hydrogenation to methanol,promoting the carbon emission reduction in steel industry.
基金supported by Ningbo Science and Technology Bureau,China(Nos.2021Z0472021Z04)+3 种基金the Department of Agriculture and Rural Development of Zhejiang Province,China(No.2022SNJF024)the Outstanding Team Program of Shanghai Academy of Agricultural Science 425,China(No.Hu-Nong-Ke-Zhuo 2022(008))the National Agricultural Experimental Station for Agricultural Environment,Fengxian,China(No.NAES035AE03)the K.C.Wong Magna Fund in Ningbo University,China。
文摘Elucidating the microbial mechanisms that trigger Fusarium wilt represents a key step in addressing the barriers to sustainable cropping.However,from the perspective of the complete microbiome,the integrated role of soil nutrients and microbial community in the fields with different rates of wilt disease remains unclear.In this study,we examined the potential interrelationships among the nutrients,bacteria,fungi,and protists in rhizospheric soils collected from the fields with watermelon cropping for 7 years at the Zhuanghang Experimental Station of Shanghai Academy of Agricultural Sciences,China.The soils collected were characterized by a high(HW,81.25%)or low(LW,6.25%)wilting rate.The HW soil was found to contain a higher abundance of Fusarium oxysporum(1.30-fold higher)than the LW soil,along with higher contents of available phosphorus(1.31-fold higher)and available potassium(2.39-fold higher).In addition,the interkingdom correlation between protists and bacteria in the HW soil was 2.08-fold higher than that in the LW soil.Furthermore,structural equation modeling revealed that an excess of soil available potassium enhanced the predation by potentially detrimental phagotrophic protists on potentially beneficial bacteria.In summary,our findings indicated that a balanced nutrient input and the interactions between protists(Cercomonas and Colpoda)and beneficial bacteria(Bacillus)played important roles in controlling the incidence of watermelon Fusarium wilt.
基金financially supported by the National Key R&D Program of China(No.2022YFB3504700)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0400304)the Research Fund of Key Laboratory of Rare Earth,Chinese Academy of Sciences(No.E32PF00116)。
文摘Efficient,safe,and economical hydrogen storage technology is vital for hydrogen’s broad use as an energy carrier,with V-based BCC alloys standing out for their high theoretical storage capacity.However,the high cost of V has restricted their practical application.In this work,a cost-effective Ti–Cr–(Fe V80)alloy was successfully synthesized through a pre-refinement process involving the addition of Y/Zr to the Fe V80 alloy.The resulting Ti_(27)Cr_(27)(Fe V80+Y)_(46)alloy exhibited an effective dehydriding capacity of 2.3 wt%,with a capacity retention rate of 97.2%after 200 cycles.Through the analysis of HSC Chemistry 6.0 software and backscattered electron(BSE),it has been discovered that the prerefinement process significantly reduces the presence of Al,Si,and O impurities,leading to improved compositional uniformity.After the re-refinement,the formation of the Ti–rich phases had been notably curbed.This,along with a marked decrease in the pressure–composition–temperature(PCT)curve’s slope factor from 1.58 to 0.36,results in enhanced hydriding capacity(from 3.2 wt%to 3.7 wt%),reversible dehydriding capacity(from 2.0 wt%to 2.3 wt%),and a remarkable increase in the capacity retention rate(from 75.8%to 97.2%).The kinetics and thermodynamic properties of the alloys were calculated using the Arrhenius and Van’t Hoff equations,providing insights into their performance characteristics.The mechanism behind the alloy’s improved cyclic stability has been elucidated through an analysis of lattice distortion and X-ray photoelectron spectroscopy(XPS).These findings open new routes for the development of cost-effective Fe V80-based hydrogen storage materials.
基金funded by Key Laboratory of Energy Conversion and Storage Technology(Southern University of Science and Technology)Ministry of Education+1 种基金Guangdong Innovative and Entrepreneurial Research Team Program(grant No.2016ZT06N500)Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(grant No.2018B030322001).
文摘The efficient and stable operation of proton exchange membrane fuel cells(PEMFCs)in practical applications can be adversely affected by various contaminants.This study delves into the impact of Cr_(2)(SO_(4))_(3)contamination on the gas diffusion layer(GDL)and PEMFC performance,systematically analyzing the physicochemical property changes and their correlation with electrochemical performance.The results indicate that after post-treatment,the GDL surface exhibited exposed carbon fibers,cracks,and large pores in the microporous layer(MPL),with a noticeable detachment of PTFE.There was a marked reduction in C and F element signals,an increase in O element signals,deposition of Cr_(2)(SO_(4))_(3),formation of C=O and C=C bonds,appearance of Cr_(2)(SO_(4))_(3)characteristic peaks,and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology,structure,and chemical composition.The decline in mechanical strength and thermal stability,and increased surface roughness and resistance negatively impacted fuel cell performance.At high current densities,the emergence of water flooding increased mass transfer resistance from 0.1Ωcm^(2)to 1.968Ωcm^(2),with a maximum power density decay rate reaching 71.17%.This study reveals the significant negative impact of Cr_(2)(SO_(4))_(3)contamination on GDL and fuel cell performance,highlighting that changes in surface structure,reduced hydrophobicity,and increased mass transfer resistance are primary causes of performance degradation.The findings provide crucial insights for improving GDL materials,optimizing fuel cell manufacturing and operation processes,and addressing contamination issues in practical applications.
基金supported by the Natural Science Research Project of Jiangsu Higher Education Institutions(No.23KJD150005)the Scientific Research Project of Nanjing Xiaozhuang University(No.2022NXY29).
文摘Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were successfully synthesized by hydrothermal,annealing and phosphating methods on nickel foam(NF).The unusual shape of the sea urchin facilitates gas release and mass transfer and increases the interaction between catalysts and electrolytes.The Ni_(4)Mo/NF and Ni-Mo-P/NF electrodes only need overpotentials of 72 and 197 mV to reach 50 mA·cm^(−2) under alkaline conditions for hydrogen evolution reaction and oxygen evolution reaction,respectively.The Ni_(4)Mo/NF and Ni-Mo-P/NF asymmetric electrodes were used as anode and cathode for the overall water splitting,respectively.In 1.0 M KOH,at a voltage of 1.485 V,the electrolytic device generated 50 mA·cm^(−2) current density,maintaining for 24 h without reduction.The labor presents a simple method to synthesize a highly active,low-cost,and strongly durable self-supporting electrode for over-water splitting.
基金support from the National Natural Science Foundation of China(No.52201278,No.21975260,No.22379103,No.22409074).
文摘The metal-carbon dioxide batteries,emerging as high-energy-density energy storage devices,enable direct CO_(2)utilization,offering promising prospects for CO_(2)capture and utilization,energy conversion,and storage.However,the electrochemical performance of M-CO_(2)batteries faces significant challenges,particularly at extreme temperatures.Issues such as high overpotential,poor charge reversibility,and cycling capacity decay arise from complex reaction interfaces,sluggish oxidation kinetics,inefficient catalysts,dendrite growth,and unstable electrolytes.Despite significant advancements at room temperature,limited research has focused on the performance of M-CO_(2)batteries across a wide-temperature range.This review examines the effects of low and high temperatures on M-CO_(2)battery components and their reaction mechanism,as well as the advancements made in extending operational ranges from room temperature to extremely low and high temperatures.It discusses strategies to enhance electrochemical performance at extreme temperatures and outlines opportunities,challenges,and future directions for the development of M-CO_(2)batteries.
基金Supported by Finance Science and Technology Project of Hainan Province under Grant No.ZDKJ2021027the National Natural Science Foundation of China under Grant No.52231012.
文摘The deep seabed is known for its abundant reserves of various mineral resources.Notably,the Clarion Clipperton(C-C)mining area in the northeast Pacific Ocean,where China holds exploration rights,is particularly rich in deep-sea polymetallic nodules.These nodules,which are nodular and unevenly distributed in seafloor sediments,have significant industrial exploitation value.Over the decades,the deep-sea mining industry has increasingly adopted systems that combine rigid and flexible risers supported by large surface mining vessels.However,current systems face economic and structural stability challenges,hindering the development of deep-sea mining technology.This paper proposes a new structural design for a deep-sea mining system based on flexible risers,validated through numerical simulations and experimental research.The system composition,function and operational characteristics are comprehensively introduced.Detailed calculations determine the production capacity of the deep-sea mining system and the dimensions of the seabed mining subsystem.Finite element numerical simulations analyze the morphological changes of flexible risers and the stress conditions at key connection points under different ocean current incident angles.Experimental research verifies the feasibility of collaborative movement between two tethered underwater devices.The proposed deep-sea mining system,utilizing flexible risers,significantly advances the establishment of a commercial deep-sea mining system.The production calculations and parameter determinations provide essential references for the system’s future detailed design.Furthermore,the finite element simulation model established in this paper provides a research basis,and the method established in this paper offers a foundation for subsequent research under more complex ocean conditions.The control strategy for the collaborative movement between two tethered underwater devices provides an effective solution for deep-sea mining control systems.
基金Supported by Clinical Cohort Construction Program of Peking University Third Hospital,No.BYSYDL2023005Peking University Third Hospital Innovation Transformation Fund,No.BYSYZHZB2023105.
文摘BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,which caused a marked increase in surgical difficulty and risk compared to treatment for typical choledocholithiasis.This phenomenon has not been described in previous studies.AIM To propose the ice-breaking sign and evaluate its influence on treatment strategies for choledocholithiasis.METHODS Using a retrospective case-control study design,patients who were diagnosed with common bile duct stones and admitted to the Emergency Department of Peking University Third Hospital between January 2018 and December 2023 were included.Propensity score matching was used to match cases and controls.Univariate analysis was conducted to assess the differences in clinical data between the two groups of patients.RESULTS There were no significant differences in the baseline data between the two groups,except for higher incidence of jaundice,alkaline phosphatase and total bilirubin in the ice-breaking sign group.Compared to the control group,the ice-breaking sign group had lower success rates for endoscopic retrograde cholangiopancreatography(25.0%vs 81.8%,P=0.006)and laparoscopic common bile duct exploration(69.4%vs 93.8%,P=0.007),longer operation time(148.04±60.55 minutes vs 106.15±35.21 minutes,P=0.001),higher likelihood of T-tube placement(62.2%vs 31.3%,P=0.016)and using lithotripsy techniques during surgery(29.7%vs 0%,P=0.001),more intraoperative bleeding[25.0(20.0-50.0)mL vs 10.0(10.0-20.0)mL,P<0.001]and longer postoperative hospital stay[6.50(5.0-9.0)days vs 5.50(3.0-6.50)days,P=0.002].The ice-breaking sign group showed significantly more dilatation in the proximal than distal bile duct.CONCLUSION The ice-breaking sign,a newly identified radiological phenomenon,may influence therapeutic decisions in choledocholithiasis,suggesting laparoscopic common bile duct exploration as the preferred approach over endoscopic retrograde cholangiopancreatography in patients exhibiting this sign.
基金supported by the National Natural Science Foundation of China(Nos.21971221,21401162)the Natural Science Foundation of Jiangsu Province(BK20241930)+3 种基金the Yangzhou University Interdisciplinary Research Foundation for Chemistry Discipline(yzuxk202010)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(grant number KYCX22_3467,KYCX24_3727)High-Level Entrepreneurial and Innovative Talents Program of Jiangsu’Qing Lan Project’in Colleges and Universities of Jiangsu Province。
文摘Aqueous Cu-S batteries(ACSBs)offer a promising energy storage solution by leveraging the unique redox properties of Cu^(2+)ions,enabling high theoretical capacities through a four-electron transfer reaction.These advantages are coupled with inherent safety and low cost,making ACSBs a compelling alternative to traditional batteries.However,the practical application of ACSBs is hindered by the low conductivity of sulfur and the high energy barrier associated with phase transitions,which limit material utilization and reaction kinetics.Herein,we propose for the first time a multifunctional organic small-molecule polysulfide catalyst,Zn(phen)S_(6),and successfully convert them into nanocapsules that are homogeneously dispersed on the cathode surface,effectively increasing the catalytic active sites.Moreover,this complex undergoes reversible reactions during cycling,releasing zinc ions that form a dense protective layer on the anode during charging,effectively inhibiting dendrite growth.Meanwhile,Zn(phen)S_(6)interacts with Cu^(2+)ions to undergo an in-situ solid-state transformation into a novel catalyst,[Cu(phen)(H_(2)O)_(2)SO_(4)]_(n).This catalyst not only accelerates electron transfer but also serves as an ion transport channel,significantly boosting reaction kinetics.This battery demonstrates exceptional stability,retaining 97.7%of its initial capacity after 1200 cycles at a high current density of 10 A g^(-1).Furthermore,it maintains an impressive capacity of 1157 m Ah g^(-1)after 1600 cycles at 20 A g^(-1).This work provides pivotal insights into the design and application of molecular catalysts,opening new pathways for advancing Cu-S battery technologies.
基金supported by the Anhui Provincial Department of Education Outstanding Young Teachers Cultivation Key Project(No.YQZD2023046)the Anhui University of Traditional Chinese Medicine School Talent Support Program Project(Nos.DT2400000222 and DT2100000545)。
文摘Objective:To elucidate the specific mechanisms by which electroacupuncture(EA)alleviates anxiety and fear behaviors associated with posttraumatic stress disorder(PTSD),focusing on the role of lipocalin-2(Lcn2).Methods:The PTSD mouse model was subjected to single prolonged stress and shock(SPS&S),and the animals received 15 min sessions of EA at Shenmen acupoint(HT7).Behavioral tests were used to investigate the effects of EA at HT7 on anxiety and fear.Western blotting and enzyme-linked immunosorbent assay were used to quantify Lcn2 and inflammatory cytokine levels in the prefrontal cortex(PFC).Additionally,the activity of PFC neurons was evaluated by immunofluorescence and in vivo electrophysiology.Results:Mice subjected to SPS&S presented increased anxiety-and fear-like behaviors.Lcn2 expression in the PFC was significantly upregulated following SPS&S,leading to increased expression of the proinflammatory cytokines tumor necrosis factor-a and interleukin-6 and suppression of PFC neuronal activity.However,EA at HT7 inhibited Lcn2 release,reducing neuroinflammation and hypoexcitability in the PFC.Lcn2 overexpression mitigated the effects of EA at HT7,resulting in anxiety-and fear-like behaviors.Conclusion:EA at HT7 can ameliorate PTSD-associated anxiety and fear,and its mechanism of action appears to involve the inhibition of Lcn2-mediated neural activity and inflammation in the PFC.
基金support of the National Natural Science Foundation of China(Grant No.52074332).
文摘Natural gas hydrates(hereinafter referred to as hydrates)are a promising clean energy source.However,their current development is far from reaching commercial exploitation.Reservoir stimulation tech-nology provides new approaches to enhance hydrate development effectiveness.Addressing the current lack of quantitative and objective methods for evaluating the fracability of hydrate reservoirs,this study clarifies the relationship between geological and engineering fracability and proposes a comprehensive evaluation model for hydrate reservoir fracability based on grey relational analysis and the criteria importance through intercriteria correlation method.By integrating results from hydraulic fracturing experiments on hydrate sediments,the fracability of hydrate reservoirs is assessed.The concept of critical construction parameter curves for hydrate reservoirs is introduced for the first time.Additionally,two-dimensional fracability index evaluation charts and three-dimensional fracability construction condition discrimination charts are established.The results indicate that as the comprehensive fracability index increases,the feasibility of forming fractures in hydrate reservoirs improves,and the required normalized fracturing construction parameters gradually decrease.The accuracy rate of the charts in judging experimental results reached 89.74%,enabling quick evaluations of whether hydrate reservoirs are worth fracturing,easy to fracture,and capable of being fractured.This has significant engineering implications forthehydraulicfracturingof hydratereservoirs.
文摘This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regression.Taking City Commercial Bank A as an instance,the model identifies 12.3%redundant positions and matches jobs with business scale.Additionally,the study proposes a“staffing effectiveness salary”system,providing a framework for optimizing commercial bank human capital in the digital age.
基金Science and Technology Planning Project of Guangdong Province(2023B1212060048).
文摘The Suizhou meteorite is a heavily shock-met-amorphosed L6 chondrite which contains thin shock melt veins.So far,26 high-pressure phases have been identified from the meteorite.Among the high-pressure phases,ten of them were approved as new minerals which include tuite,xieite,wangdaodeite,chenmingite,hemleyite,poirierite,asimowite,hiroseite,elgoresyite,and ohtaniite,by the Commission on New Minerals,Nomenclature and Classification of the International Mineralogical Association.Other high-pressure phases identified from the meteorite are ahrensite,akimotoite,bridgmanite,lingunite,magnesiowüstite,majorite,majorite-pyrope_(ss),maskelynite,riesite,ringwoodite,wadsleyite,and 5 other phases including phase A,vitrified phase B and phase C,phase D(Ca-rich majorite),and partly inverted ringwoodite.The occurrence and abundance of high-pressure phases makes this meteorite the one with the richest variety of high-pressure minerals to date.
基金supported by the Shandong Provincial Natural Science Foundation for Distinguished Young Scholars(Grant No.ZR2024JQ012)This research was financially supported by the National Natural Science Foundation of China(General Program,Grant No.52474069)This research was financially supported by the Natural Gas Research Institute of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.(Grant No.TYTY0824SFW0003).
文摘Hydraulic fracturing is a key technology for the efficient development of deep oil and gas reservoirs.However,fracture propagation behavior is influenced by rock elastoplasticity and thermal stress,making it difficult for traditional linear elastic models to accurately describe its dynamic response.To address this,this study employs the Continuum-Discontinuum Element Method(CDEM),incorporating an elastoplastic constitutive model,thermo-hydro-mechanical(THM)coupling effects,and cohesive zone characteristics at the fracture tip to establish a numerical model for hydraulic fracture propagation in deep elastoplastic reservoirs.A systematic investigation was conducted into the effects of fluid viscosity,reservoir temperature,injection rate,elastic modulus,and horizontal stress difference on fracture propagation.The findings show that a larger horizontal stress differential results in a more rectangular fracture geometry,a shorter fracture length,and a wider fracture.An increase in elastic modulus has a negligible impact on fracture length but reduces fracture width,resulting in a rounded rectangular morphology.Elevated reservoir temperature induces thermal tensile stress around the fracture,mitigating in-situ stress effects and reducing both breakdown and propagation pressures.Higher injection rates and fluid viscosity increase fracture initiation difficulty,promoting shorter but wider fractures with enhanced height growth beyond interlayer barriers.Additionally,horizontal stress significantly affects near-fracture plastic deformation:when the stress difference increases from 10 to 25 MPa,the maximum cumulative plastic strain in the surrounding rock rises by 66.67%.By integrating elastoplasticity and thermal stress effects,this study overcomes the limitations of conventional hydraulic fracturing simulations,offering novel insights for optimizing extraction strategies in deep unconventional reservoirs.
基金Yancheng Science and Technology Bureau(YCBK2023027)。
文摘EMC anechoic chamber is used for radiation emission and radiation immunity test,and the wireless performance of products needs to be tested in OTA anechoic chamber.With more and more electronic and electrical equipment with wireless communication function,the rapid construction of a compatible OTA test system in the existing EMC anechoic chamber can save the cost and space of enterprises and third-party laboratories that already have EMC anechoic chamber.In this paper,the OTA test system is built in the existing EMC anechoic room,the ripple calibration test is carried out according to the OTA standard,the TRP and TIS tests are carried out on two test samples with different wireless communication standards,and the test samples are taken to the OTA anechoic room for a comparison test.The comparison between the ripple calibration data and the OTA test data showed that the EMC anechoic chamber could perform OTA test without affecting the original test ability.The data results provide a basis for the implementation of EMC anechoic chamber compatibility upgrade OTA test,and provide reference for further optimization of the compatible test system,reduction of test differences,and the design of anechoic chamber integrating two test functions.
基金supported by the National Natural Science Foundation of China(22275072 and 62105184)the Natural Science Foundation of Guangdong Province(2020A1515010622)+1 种基金the Project of Science and Technology of Guangzhou(2024A04J3712)the Teli Young Scholar Program of Beijing Institute of Technology.
文摘Donor-acceptor(D-A)compounds are particularly important in optoelectronic and biological applications.However,they are normally synthesized in the presence of transition metal catalysts.Herein,we report a metal-free method by a complexmediated nucleophilic aromatic substitution of aryl nitriles with amines.The method can lead to rich D-A type aggregation-induced emission luminogens(AIEgens)with tunable properties.They emit from deep-blue to yellow-green and possess high photoluminescence quantum yields up to 70.5%in the aggregate state.Interestingly,the suppression of intramolecular flapping is proved to play an indispensable role in the AIE behavior,which is different from the mechanism met in other AIEgens.Moreover,the biocompatible AIEgens possess specific staining of lipid droplets in HeLa cells and the superiority of identifying fatty liver over traditional Oil Red O staining is exhibited.
