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The counteracting role of nitrate during ammonium toxicity in plants
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作者 Mikel Rivero-Marcos Aitziber Calleja-Satrustegui Idoia Ariz 《Horticultural Plant Journal》 2026年第1期49-61,共13页
Ammonium toxicity in plants remains poorly understood despite extensive research.While nitrate is known to benefit plant growth,the synergistic effects of nitrate in mitigating ammonium toxicity,even at low concentrat... Ammonium toxicity in plants remains poorly understood despite extensive research.While nitrate is known to benefit plant growth,the synergistic effects of nitrate in mitigating ammonium toxicity,even at low concentrations,are not fully elucidated.This review delves into the physiological and molecular nature of this phenomenon.To date,nitrate-dependent alleviation of ammonium toxicity is the result of cumulative consequences of the role of nitrate as a nutrient and signal in plant performance.The ability to counteract the ammonium-induced acidification through nitrate uptake and metabolism,the enhancement of potassium uptake as an essential nitrate counterion,and the nitratedependent signaling of key factors involved in ammonium assimilation,ROS scavenging,and growth hormone biosynthesis,are the most relevant hallmarks.In addition,evidence suggests that the availability of nitrate and ammonium has driven ecological selection in plants,determining current N preferences,and may have led to the selection of nitrate-dependent and ammonium-sensitive domesticated crops and the inefficient use of N fertilizers in agriculture.As ammonium toxicity limits N fertilization options and reduces agricultural yields,when it could be a more sustainable and cheaper alternative to nitrate,this review provides a better understanding of how plants use nitrate to counteract the problematic aspects of ammonium nutrition. 展开更多
关键词 Ammonium toxicity NITRATE Ion uptake PHYTOHORMONES PHOTOSYNTHESIS POTASSIUM Proton stress
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Radiation hardness of 1.2 kV SiC power devices with advanced edge termination structures under proton irradiation
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作者 Sangyeob Kim Jeongtae Kim +3 位作者 Dong-Seok Kim Hyuncheol Bae Min-Woo Ha Ogyun Seok 《Journal of Semiconductors》 2026年第1期83-89,共7页
This work presents a systematic analysis of proton-induced total ionizing dose(TID)effects in 1.2 k V silicon carbide(SiC)power devices with various edge termination structures.Three edge terminations including ring-a... This work presents a systematic analysis of proton-induced total ionizing dose(TID)effects in 1.2 k V silicon carbide(SiC)power devices with various edge termination structures.Three edge terminations including ring-assisted junction termination extension(RA-JTE),multiple floating zone JTE(MFZ-JTE),and field limiting rings(FLR)were fabricated and irradiated with45 Me V protons at fluences ranging from 1×10^(12) to 1×10^(14) cm^(-2).Experimental results,supported by TCAD simulations,show that the RA-JTE structure maintained stable breakdown performance with less than 1%variation due to its effective electric field redistribution by multiple P+rings.In contrast,MFZ-JTE and FLR exhibit breakdown voltage shifts of 6.1%and 15.2%,respectively,under the highest fluence.These results demonstrate the superior radiation tolerance of the RA-JTE structure under TID conditions and provide practical design guidance for radiation-hardened Si C power devices in space and other highradiation environments. 展开更多
关键词 SIC proton irradiation edge termination radiation hardness TID effects
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Advancements and Innovations in Low-Temperature Hydrogen Electrochemical Conversion Devices Driven by 3D Printing Technology
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作者 Min Wang Xiuyue Wang +6 位作者 Enyang Sun Zhenye Kang Fan Gong Bin Hou Gaoqiang Yang Mingbo Wu Feng‑Yuan Zhang 《Nano-Micro Letters》 2026年第2期599-630,共32页
3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make i... 3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems. 展开更多
关键词 3D printing HYDROGEN Proton exchange membrane fuel cells Water electrolyzers
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Boosting high-performance in Zr-rich side protonic solid oxide electrolysis cells by optimizing functional interlayer 被引量:1
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作者 Chunmei Tang Ning Wang +3 位作者 Sho Kitano Hiroki Habazaki Yoshitaka Aoki Siyu Ye 《Green Energy & Environment》 SCIE EI CAS 2025年第1期150-160,共11页
Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SO... Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SOECs with Zr-rich electrolyte,called Zr-rich side P-SOECs,possess high thermodynamically stability under high steam concentrations but the large reaction resistances and the current leakage,thus the inferior performances.In this study,an efficient functional interlayer Ba_(0.95)La_(0.05)Fe_(0.8)Zn_(0.2)O_(3-δ)(BLFZ)in-between the anode and the electrolyte is developed.The electrochemical performances of P-SOECs are greatly enhanced because the BLFZ can greatly increase the interface contact,boost anode reaction kinetics,and increase proton injection into electrolyte.As a result,the P-SOEC yields high current density of 0.83 A cm^(-2) at 600℃ in 1.3 Vamong all the reported Zr-rich side cells.This work not only offers an efficient functional interlayer for P-SOECs but also holds the potential to achieve P-SOECs with high performances and long-term stability. 展开更多
关键词 Functional interlayer Zr-rich side electrolyte Protonic solid oxide electrolysis cells Current density Faradaic efficiency
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Nanofiber-based polymer electrolyte membranes for fuel cells 被引量:2
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作者 Ning Liu Shuguang Bi +5 位作者 Yi Zhang Ying Ou Chunli Gong Jianhua Ran Yihuang Chen Yingkui Yang 《Carbon Energy》 2025年第4期1-35,共35页
Developing low-cost and high-performance nanofiber-based polyelectrolyte membranes for fuel cell applications is a promising solution to energy depletion.Due to the high specific surface area and one-dimensional longr... Developing low-cost and high-performance nanofiber-based polyelectrolyte membranes for fuel cell applications is a promising solution to energy depletion.Due to the high specific surface area and one-dimensional longrange continuous structure of the nanofiber,ion-charged groups can be induced to form long-range continuous ion transfer channels in the nanofiber composite membrane,significantly increasing the ion conductivity of the membrane.This review stands apart from previous endeavors by offering a comprehensive overview of the strategies employed over the past decade in utilizing both electrospun and natural nanofibers as key components of proton exchange membranes and anion exchange membranes for fuel cells.Electrospun nanofibers are categorized based on their material properties into two primary groups:(1)ionomer nanofibers,inherently endowed with the ability to conduct H+(such as perfluorosulfonic acid or sulfonated poly(ether ether ketone))or OH-(e.g.,FAA-3),and(2)nonionic polymer nanofibers,comprising inert polymers like polyvinylidene difluoride,polytetrafluoroethylene,and polyacrylonitrile.Notably,the latter often necessitates surface modifications to impart ion transport channels,given their inherent proton inertness.Furthermore,this review delves into the recent progress made with three natural nanofibers derived from biodegradable cellulose—cellulose nanocrystals,cellulose nanofibers,and bacterial nanofibers—as crucial elements in polyelectrolyte membranes.The effect of the physical structure of such nanofibers on polyelectrolyte membrane properties is also briefly discussed.Lastly,the review emphasizes the challenges and outlines potential solutions for future research in the field of nanofiber-based polyelectrolyte membranes,aiming to propel the development of high-performance polymer electrolyte fuel cells. 展开更多
关键词 anion exchange membranes fuel cells NANOFIBERS proton exchange membranes
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Confined proton transport in water-containing layered manganese oxide electrodes 被引量:1
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作者 Wenwei Cai Feng Pan Shunning Li 《Chinese Journal of Structural Chemistry》 2025年第5期15-18,共4页
Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of prot... Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of proton transport in transition metal oxides,which dates back to 1971[3]when RuO_(2) was discovered to be capable of storing protons via reversible redox reactions[4].In aqueous electrolytes,the thin film RuO_(2) electrode exhibits a surface pseudocapacitive behavior[5],which could be modified by the structural water in its hydrated form due to the facile Grotthuss hopping mode of protons along the established hydrogen bonds inside the bulk phase[6].Soon later,Goodenough et al.reported the capacitor-like behavior of amorphous MnO_(2)·xH_(2)O electrode in an aqueous KCl electrolyte[7],and further studies on the hydrated MnO_(2) electrodes prepared by sol-gel processes have soon discovered that the intercalation of protons from aqueous electrolytes plays an indispensable role in the charge storage mechanism[8].In recent years,the research interest on rechargeable aqueous batteries has fueled the renaissance of mechanistic study of proton transport in transition metal oxides[9],which can operate as cathodes or anodes via a topotactic insertion mechanism similar to that in Li-ion batteries[10].However,due to the challenges for experimental detection of local chemical environments of the inserted protons,a comprehensive understanding of proton dynamic behavior in these electrodes remains largely lacking. 展开更多
关键词 transition metal oxideswhich storing protons inorganic materials thin film ruo proton transport reversible redox reactions understanding proton dynamic behavior electrochemical energy storage one
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Precision-Engineered Construction of Proton-Conducting Metal-Organic Frameworks 被引量:1
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作者 Liyu Zhu Hongbin Yang +2 位作者 Ting Xu Feng Shen Chuanling Si 《Nano-Micro Letters》 2025年第4期230-274,共45页
Proton-conducting materials have attracted considerable interest because of their extensive application in energy storage and conversion devices.Among them,metal-organic frameworks(MOFs)present tremendous development ... Proton-conducting materials have attracted considerable interest because of their extensive application in energy storage and conversion devices.Among them,metal-organic frameworks(MOFs)present tremendous development potential and possibilities for constructing novel advanced proton conductors due to their special advantages in crystallinity,designability,and porosity.In particular,several special design strategies for the structure of MOFs have opened new doors for the advancement of MOF proton conductors,such as charged network construction,ligand functionalization,metal-center manipulation,defective engineering,vip molecule incorporation,and pore-space manipulation.With the implementation of these strategies,proton-conducting MOFs have developed significantly and profoundly within the last decade.Therefore,in this review,we critically discuss and analyze the fundamental principles,design strategies,and implementation methods targeted at improving the proton conductivity of MOFs through representative examples.Besides,the structural features,the proton conduction mechanism and the behavior of MOFs are discussed thoroughly and meticulously.Future endeavors are also proposed to address the challenges of proton-conducting MOFs in practical research.We sincerely expect that this review will bring guidance and inspiration for the design of proton-conducting MOFs and further motivate the research enthusiasm for novel proton-conducting materials. 展开更多
关键词 MOFS Proton conduction Porous materials Fuel cells
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Role of Helicobacter pylori infection and the risk of cholelithiasis 被引量:1
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作者 Nicolò Fabbri Salvatore Greco +3 位作者 Antonio Pesce Francesco Virgilio Danila Romeo Carlo V Feo 《World Journal of Gastroenterology》 2025年第8期152-154,共3页
This article aims to deepen the understanding of the role of Helicobacter pylori(H.pylori)infection in the development of cholelithiasis,initiated by the article by Yao et al,who investigated the potential link betwee... This article aims to deepen the understanding of the role of Helicobacter pylori(H.pylori)infection in the development of cholelithiasis,initiated by the article by Yao et al,who investigated the potential link between H.pylori infection and the development of cholelithiasis through a multicenter retrospective study on an Asian population of over 70000 participants.They also performed a compre-hensive analysis of previously published studies on H.pylori and cholelithiasis,finding a positive association therein[odds ratio(OR)=1.103,P=0.049].Patients positive for H.pylori also had lower levels of total and direct bilirubin,but higher levels of total cholesterol and low-density lipoprotein cholesterol compared to uninfected patients(P<0.05).Cohort studies have confirmed that H.pylori is a risk factor for cholelithiasis(P<0.0001),and aggregate analyses of case-control and cross-sectional studies have shown a positive association between H.pylori and cholelithiasis in Asia(OR=1.599,P=0.034),but not in Europe(OR=1.277,P=0.246).Moreover,H.pylori appears to be related to a higher ratio of choledocho-lithiasis/cholecystolithiasis(OR=3.321,P=0.033).The authors conclude that H.pylori infection is positively correlated with cholelithiasis,particularly with the choledocholithiasis phenotype,especially in Asia,and it is potentially related to bilirubin and cholesterol metabolism. 展开更多
关键词 Helicobacter pylori Helicobacter pylori infection CHOLELITHIASIS Proton pump inhibitors CHOLEDOCHOLITHIASIS
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Exploring small intestinal bacterial overgrowth in functional upper gastrointestinal disorder:A comprehensive case-control study 被引量:1
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作者 Bhaswati C Acharyya Meghdeep Mukhopadhyay 《World Journal of Clinical Pediatrics》 2025年第3期105-110,共6页
BACKGROUND Small intestinal bacterial overgrowth(SIBO)is suspected and excluded frequently in functional gastrointestinal(GI)disorders.Children presenting with various esophago-gastro-duodenal(upper GI)symptoms are ra... BACKGROUND Small intestinal bacterial overgrowth(SIBO)is suspected and excluded frequently in functional gastrointestinal(GI)disorders.Children presenting with various esophago-gastro-duodenal(upper GI)symptoms are rarely subjected to investig-ations for SIBO.AIM To estimate the frequency of SIBO in children having functional upper GI sym-ptoms(as cases)and to compare the result of the SIBO status to that of the con-trols.METHODS Children aged 6 to 18 who presented with upper GI symptoms were selected for the study.All children were subjected to upper GI endoscopy before being advised of any proton pump inhibitors(PPIs).Children with normal endoscopy were assigned as cases,and children having any endoscopic lesion were design-ated as controls.Both groups were subjected to a glucose-hydrogen breath test by Bedfont Gastrolyser.RESULTS A total of 129 consecutive children who were naive to PPIs and had normal ba-seline investigations were included in the study.Among them,67 patients had endoscopic lesions and served as the control group,with six cases being excluded due to the presence of Helicobacter pylori in gastric biopsies.Sixty-two children with normal endoscopy results formed the case group.In the case group,35 children(59%)tested positive for hydrogen breath tests,compared to 13 children(21%)in the control group.The calculated odds ratio was 5.38(95%confidence interval:2.41-12.0),which was statistically significant.Further analysis of symptoms revealed that nausea,halitosis,foul-smelling eructation,and epigastric fullness were positive predictors of SIBO.CONCLUSION It is worthwhile to investigate and treat SIBO in all children presenting with upper GI symptoms that are not explained by endoscopy findings. 展开更多
关键词 Small intestinal Bacterial overgrowth Hydrogen breath test Functional gastrointestinal Proton pump inhibitor
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Mind the gut:Navigating the complex landscape of gastroprotection in neurosurgical patients 被引量:1
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作者 Subeikshanan Venkatesan Brandon Lucke-Wold 《World Journal of Gastroenterology》 2025年第8期1-8,共8页
Neurosurgical patients,including those with severe traumatic brain injury,spinal cord injury,stroke,or raised intracranial pressure,are at heightened risk for stress ulcers and aspiration pneumonitis,leading to signif... Neurosurgical patients,including those with severe traumatic brain injury,spinal cord injury,stroke,or raised intracranial pressure,are at heightened risk for stress ulcers and aspiration pneumonitis,leading to significant morbidity and mortality.These patients are typically managed through both pharmacological interventions[e.g.,proton pump inhibitors(PPIs),histamine 2(H2)antagonists,sucralfate]and non-pharmacological measures(e.g.,nasogastric decompression,patient positioning)to mitigate adverse outcomes.The pathogenesis of stress ulcers in neurosurgical patients is multifactorial,but the routine use of stress ulcer prophylaxis remains controversial.While gastric acid suppression with H2 rece-ptor antagonists and PPIs is commonly employed,concerns have arisen regarding the association between elevated gastric pH,bacterial colonization,and ventilator-associated pneumonia.The lack of comprehensive data on gastroprotection in critically ill neurosurgical patients,who face a greater risk than non-neurosurgical counterparts,further complicates this issue.Recent studies,such as one by Gao et al on the efficacy of vonoprazan-amoxicillin dual therapy in elderly patients,highlight the potential of novel therapies,but the influence of pre-existing conditions like Helicobacter pylori infection remains unclear.Non-pharmacological interventions,including nasogastric decompression and early enteral nutrition,are critical in improving outcomes but require further research to refine strategies.This editorial underscores the need for tailored approaches and encourages further investigation into optimal gastroprotective strategies for neurosurgical patients. 展开更多
关键词 GASTROPROTECTION NEUROSURGERY Stress ulcer Proton pump inhibitor Histamine 2 receptor antagonist Vonoprazan Nasogastric tube Enteral nutrition
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Proton exchange membrane-based electrocatalytic systems for hydrogen production 被引量:1
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作者 Yangyang Zhou Hongjing Zhong +6 位作者 Shanhu Chen Guobin Wen Liang Shen Yanyong Wang Ru Chen Li Tao Shuangyin Wang 《Carbon Energy》 2025年第1期292-311,共20页
Hydrogen energy from electrocatalysis driven by sustainable energy has emerged as a solution against the background of carbon neutrality.Proton exchange membrane(PEM)-based electrocatalytic systems represent a promisi... Hydrogen energy from electrocatalysis driven by sustainable energy has emerged as a solution against the background of carbon neutrality.Proton exchange membrane(PEM)-based electrocatalytic systems represent a promising technology for hydrogen production,which is equipped to combine efficiently with intermittent electricity from renewable energy sources.In this review,PEM-based electrocatalytic systems for H2 production are summarized systematically from low to high operating temperature systems.When the operating temperature is below 130℃,the representative device is a PEM water electrolyzer;its core components and respective functions,research status,and design strategies of key materials especially in electrocatalysts are presented and discussed.However,strong acidity,highly oxidative operating conditions,and the sluggish kinetics of the anode reaction of PEM water electrolyzers have limited their further development and shifted our attention to higher operating temperature PEM systems.Increasing the temperature of PEM-based electrocatalytic systems can cause an increase in current density,accelerate reaction kinetics and gas transport and reduce the ohmic value,activation losses,ΔGH*,and power consumption.Moreover,further increasing the operating temperature(120-300℃)of PEM-based devices endows various hydrogen carriers(e.g.,methanol,ethanol,and ammonia)with electrolysis,offering a new opportunity to produce hydrogen using PEM-based electrocatalytic systems.Finally,several future directions and prospects for developing PEM-based electrocatalytic systems for H_(2) production are proposed through devoting more efforts to the key components of devices and reduction of costs. 展开更多
关键词 ELECTROLYSIS hydrogen production proton exchange membrane
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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape 被引量:1
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作者 Xuewei Zhang Wei Zhou +13 位作者 Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao 《Journal of Energy Chemistry》 2025年第1期201-214,共14页
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for... The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors. 展开更多
关键词 Water electrolysis Hydrogen production Pulsed dynamic electrolysis Proton exchange membrane water electrolysis Mass transport
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Strategic Design of“Three-in-One”Cathode Toward Optimal Performance of Proton-Conducting Solid Oxide Fuel Cell:The Temperature Matters 被引量:1
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作者 Min-Rui Gao Meng-Nan Zhu +3 位作者 Bo-Wen Zhang Nanqi Duan Peng-Fei Sui Jing-Li Luo 《Carbon Energy》 2025年第7期49-62,共14页
“Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(... “Three-in-one”cathode,achieved via B-site heavy-doping of transition elements(typically Co,Fe)into proton-conductive perovskite,holds promise for enhancing the performance of proton-conducting solid oxide fuel cell(H-SOFC)operated below 650℃for electricity generation.However,its electrochemical behavior above 650℃,essential for improving the efficiency of H-SOFC for fuel conversion,remains insufficiently explored.It is still challenging to propose guidance for the design of“threein-one”cathode toward optimal H-SOFC performance below and above 650℃,with the prerequisite of gaining a comprehensive understanding of the roles of Co and Fe in determining the H-SOFC performance.This work is to address this challenge.Through theoretical/experimental studies,Co is identified to play a role in improving the oxygen reduction reaction(ORR)activity while Fe plays a role in facilitating the cathode/electrolyte interfacial proton conduction.Therefore,if the operating temperature is above 650℃,lowering the Co/Fe ratio in“three-in-one”cathode becomes crucial since the limiting factor shifts from ORR activity to proton conduction.Implementing this strategy,the SOFC using BaCo_(0.15)-Fe_(0.55)Zr_(0.1)Y_(0.1)Yb_(0.1)O_(3−δ)cathode achieves peak power densities of 1.67Wcm^(−2)under H-SOFC mode at 700℃and 2.32Wcm^(−2)under dual ion-conducting SOFC mode at 750℃,which are the highest reported values so far. 展开更多
关键词 “three-in-one” Co/Fe ratio oxygen reduction reaction(ORR) proton conduction proton-conducting solid oxide fuel cell(H-SOFC)
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Currents from relativistic laser-plasma interaction as a novel metrology for the system stability of high-repetition-rate laser secondary sources 被引量:1
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作者 Michael Ehret Iuliana-Mariana Vladisavlevici +16 位作者 Philip Wykeham Bradford Jakub Cikhardt Evgeny Filippov Jose Luis Henares Rubén Hernández Martín Diego de Luis JoséAntonio Pérez-Hernández Pablo Vicente Tomas Burian Enrique García-García Juan Hernández Cruz Mendez Marta Olivar Ruíz Óscar Varela Maria Dolores Rodríguez Frías João Jorge Santos Giancarlo Gatti 《Matter and Radiation at Extremes》 2025年第2期24-34,共11页
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second... This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers. 展开更多
关键词 relativistic laser plasma interaction pearson linear correlation proton spectrum cutoff energy interaction schemes ion acceleration target normal sheath accelerationthe return current return currents
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Syntheses,proton conduction,and transport mechanism of two three‑dimensional lanthanum phosphite‑oxalates
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作者 LU Yang HUANG Liangliang +2 位作者 ZHAO Wei WANG Xin BI Yanfeng 《无机化学学报》 北大核心 2025年第10期2127-2137,共11页
To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D... To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D frameworks,designated as[La(HPO_(3))(C_(2)O_(4))0.5(H_(2)O)_(2)](La‑1)and(C_(6)H_(16)N_(2))(H_(3)O)[La_(2)(H_(2)PO_(3))_(3)(C_(2)O_(4))_(3)(H_(2)O)](La‑2)(C_(6)H_(14)N_(2)=cis-2,6-dimethylpiperazine),were prepared by hydrothermal and solvothermal conduction,respectively.La‑1 was constructed with lanthanum phosphite 2D layers and C_(2)O_(4)^(2-)groups,whereas La‑2 was constructed with lanthanum oxalate 2D layers and H_(2)PO^(3-)groups.Alternating current(AC)impedance spectra indicate that the pro-ton conductivities of both compounds could reach 10^(-4)S·cm^(-1)and remain highly durable at 75℃and 98%of rela-tive humidity(RH).Due to the abundance of H-bonds in La‑2,theσof La‑2 was higher than that of La‑1.La‑1 exhibited excellent water and pH stability.CCDC:2439965,La‑1;443776,La‑2. 展开更多
关键词 OPEN-FRAMEWORK lanthanum phosphite-oxalate proton conductivity stability
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Testing Validity of the Isobaric Multiplet Mass Equation in T=3 Isospin Septet
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作者 LIU Junhao HUA Xiang ZHAO Xi 《原子核物理评论》 北大核心 2025年第2期218-222,共5页
The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin sys... The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin system where the validity of IMME have been tested up to now.Inspired by this work,I revist the mass of some isobaric analogue states with the help of recent results from advanced mass measurement experiment.It is found that the IMME holds well in A=50 and 46 isospin septet and the coefficients of IMME also follow the systematic trends.Mass excess value for^(50)Ni and^(46)Fe,is predicted to be-3932(20)keV and 898(67)keV,respectively. 展开更多
关键词 ISOSPIN IMME nuclear mass βdecay proton drip-line
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Proton pump inhibitors and all-cause mortality risk among cancer patients
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作者 Arunkumar Krishnan Carolin Victoria Schneider Declan Walsh 《World Journal of Clinical Oncology》 2025年第1期34-42,共9页
BACKGROUND Proton pump inhibitors(PPIs)are widely used,including among cancer patients,to manage gastroesophageal reflux and other gastric acid-related disorders.Recent evidence suggests associations between long-term... BACKGROUND Proton pump inhibitors(PPIs)are widely used,including among cancer patients,to manage gastroesophageal reflux and other gastric acid-related disorders.Recent evidence suggests associations between long-term PPI use and higher risks for various adverse health outcomes,including greater mortality.AIM To investigate the association between PPI use and all-cause mortality among cancer patients by a comprehensive analysis after adjustment for various confounders and a robust methodological approach to minimize bias.METHODS This retrospective cohort study used data from the TriNetX research network,with electronic health records from multiple healthcare organizations.The study employed a new-user,active comparator design,which compared newly treated PPI users with non-users and newly treated histamine2 receptor antagonists(H2RA)users among adult cancer patients.Newly prescribed PPIs(esomeprazole,lansoprazole,omeprazole,pantoprazole,or rabeprazole)users were compared to non-users or newly prescribed H2RAs(cimetidine,famotidine,nizatidine,or ranitidine)users.The primary outcome was all-cause mortality.Each patient in the main group was matched to a patient in the control group using 1:1 propensity score matching to reduce confounding effects.Multivariable Cox regression models were used to estimate hazard ratios(HRs)and 95% confidence interval(CI).RESULTS During the follow-up period(median 5.4±1.8 years for PPI users and 6.5±1.0 years for non-users),PPI users demonstrated a higher all-cause mortality rate than non-users after 1 year,2 years,and at the end of follow up(HRs:2.34-2.72).Compared with H2RA users,PPI users demonstrated a higher rate of all-cause mortality HR:1.51(95%CI:1.41-1.69).Similar results were observed across sensitivity analyses by excluding deaths from the first 9 months and 1-year post-exposure,confirming the robustness of these findings.In a sensitivity analysis,we analyzed all-cause mortality outcomes between former PPI users and individuals who have never used PPIs,providing insights into the long-term effects of past PPI use.In addition,at 1-year follow-up,the analysis revealed a significant difference in mortality rates between former PPI users and non-users(HR:1.84;95%CI:1.82-1.96).CONCLUSION PPI use among cancer patients was associated with a higher risk of all-cause mortality compared to non-users or H2RA users.These findings emphasize the need for cautious use of PPIs in cancer patients and suggest that alternative treatments should be considered when clinically feasible.However,further studies are needed to corroborate our findings,given the significant adverse outcomes in cancer patients. 展开更多
关键词 All-cause mortality CANCER Histamine-2 receptor antagonists MORTALITY MALIGNANCY Proton pump inhibitors CARCINOMA OUTCOME
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Proton Irradiation-induced Oxygen Vacancy and Metallic Indium in Black Indium Oxide for Enhancing Photothermal CO_(2) Hydrogenation
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作者 LIU Zequn WANG Cheng +3 位作者 ZENG Xiandi YAO Yingfang JIN Ziliang ZOU Zhigang 《材料科学与工程学报》 北大核心 2025年第5期697-705,714,共10页
On the surfaces of celestial bodies with no or thin atmospheres,such as the Moon and Mars,the solar wind irradiation process leads to the formation of hydrogen and helium enriched regions in the extraterrestrial soil ... On the surfaces of celestial bodies with no or thin atmospheres,such as the Moon and Mars,the solar wind irradiation process leads to the formation of hydrogen and helium enriched regions in the extraterrestrial soil particles.However,soil particles on the Earth with the similar composition lack such structures and properties.This discrepancy raises a key question whether there is a direct relationship between solar wind irradiation and the alterations in the structure and chemical performance of extraterrestrial materials.To address this question,this work investigates the effects of proton irradiation,simulating solar wind radiation,on the structure and photothermal catalytic properties of the classic catalyst In_(2)O_(3).It reveals that proton irradiation induces structural features in In_(2)O_(3) analogous to those characteristics of solar wind weathering observed in extraterrestrial materials.Furthermore,after proton beam irradiation with an energy of 30 keV and a dose of 3×10^(17) protons·cm^(-2),the methanol production yield of the In_(2)O_(3) catalyst increased to 2.6 times of its preirradiation level,and the methanol selectivity improved to 2.1 times of the original value.This work provides both theoretical and experimental support for the development of high-efficiency,radiation-resistant photothermal catalysts. 展开更多
关键词 Proton irradiation VESICULATION Photothermal CO_(2)hydrogenation Oxygen vacancy Indium oxide
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Significantly Enhanced Oxygen Reduction Reaction Activity in Co-N-C Catalysts through Synergistic Boron Doping
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作者 Chang Lan Jing-Sen Bai +8 位作者 Xin Guan Shuo Wang Nan-Shu Zhang Yu-Qing Cheng Jin-Jing Tao Yu-Yi Chu Mei-Ling Xiao Chang-Peng Liu Wei Xing 《电化学(中英文)》 北大核心 2025年第9期56-68,共13页
The weak adsorption energy of oxygen-containing intermediates on Co center leads to a considerable performance dis-parity between Co-N-C and costly Pt benchmark in catalyzing oxygen reduction reaction(ORR).In this wor... The weak adsorption energy of oxygen-containing intermediates on Co center leads to a considerable performance dis-parity between Co-N-C and costly Pt benchmark in catalyzing oxygen reduction reaction(ORR).In this work,we strategi-cally engineer the active site structure of Co-N-C via B substitution,which is accomplished by the pyrolysis of ammonium borate.During this process,the in-situ generated NH_(3)gas plays a critical role in creating surface defects and boron atoms substituting nitrogen atoms in the carbon structure.The well-designed CoB_(1)N_(3)active site endows Co with higher charge density and stronger adsorption energy toward oxygen species,potentially accelerating ORR kinetics.As expected,the resulting Co-B/N-C catalyst exhibited superior ORR performance over Co-N-C counterpart,with 40 mV,and fivefold en-hancement in half-wave potential and turnover frequency(TOF).More importantly,the excellent ORR performance could be translated into membrane electrode assembly(MEA)in a fuel cell test,delivering an impressive peak power density of 824 mW·cm^(-2),which is currently the best among Co-based catalysts under the same conditions.This work not only demon-strates an effective method for designing advanced catalysts,but also affords a highly promising non-precious metal ORR electrocatalyst for fuel cell applications. 展开更多
关键词 Oxygen reduction reaction Proton exchange membrane fuel cell Single-atom catalyst Co-N-C Boron doping
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Energetic proton radiation effects on the super large array 9k×9k CCDs used in a space telescope
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作者 WANG Zujun WANG Xiaodong +9 位作者 YANG Ye TANG Ning YAN Shixing LIU Changju GUO Xiaoqiang SHENG Jiangkun GOU Shilong LYU Wei YE Wenbo WANG Zhongming 《中国空间科学技术(中英文)》 北大核心 2025年第5期143-149,共7页
To know about the radiation effects on the super large array 9 k×9 k CCDs used in a space telescope induced by energetic protons,the experiments of the super large array 9 k×9 k charge coupled devices(CCDs)u... To know about the radiation effects on the super large array 9 k×9 k CCDs used in a space telescope induced by energetic protons,the experiments of the super large array 9 k×9 k charge coupled devices(CCDs)used in the space telescope irradiated by 60 MeV and 100 MeV protons are presented.The samples were exposed by 60 MeV and 100 MeV protons at fluences of 5×10^(9)/cm^(2) and 1×10^(10)/cm^(2),respectively.The degradations of the main performance parameters of the super large array CCDs which are paid special attention to the space telescope are investigated.The full well capacity,mean dark current,and the charge transfer inefficiency(CTI)versus proton fluence are presented,which are tested at very low temperature of-85℃.The annealing tests of 168 h were carried out after proton irradiation.The dark images before and after proton irradiation are also presented to compare the image degradation.The degradation mechanisms of the super large array CCDs irradiated by protons are analyzed.The experimental results show that the main performance parameters of the CCDs are degraded after 60 MeV and 100 MeV protons and the degradations induced by 60 MeV protons are larger than that induced by 100 MeV protons.The experimental results of the super large array CCDs irradiated by protons will provide the basic test data support for orbit life assessment of the space telescope. 展开更多
关键词 charge coupled device(CCD) proton irradiation full well capacity dark current charge transfer inefficiency(CTI)
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