期刊文献+
共找到9,996篇文章
< 1 2 250 >
每页显示 20 50 100
Can the Hypothetical Protons Emitted by the Shroud’s Man Furnish an I(z) Correlation?
1
作者 Giovanni Fazio 《Open Journal of Applied Sciences》 2024年第8期1979-1984,共6页
Recently, we have investigated the hypothesis radiative demonstrating that the two penetrated thicknesses (in air and linen) are not compatible with a single energy of the protons. Furthermore, we deduced that the dis... Recently, we have investigated the hypothesis radiative demonstrating that the two penetrated thicknesses (in air and linen) are not compatible with a single energy of the protons. Furthermore, we deduced that the distribution of energy, released by the above particles, on the burial linen has not a linear trend when the body-burial linen distance changes. Now, in this article we want to deduce the I(z) relationship, between the Image Intensity of the colour produced by protons on a linen and the z distance from the source (of Protons) and the same linen. To achieve the result in an analytical form and make a comparison with the same function extracted from the Shroud, we used the empirical expression Range-Energy for protons in air of Wilson-Brobeck. Thus, we obtain a result I(z) = Im [1 − (z/R)5/9] that is different from the one extracted from the Turin Linen I(z) = IM (1 − z/R0). We have also the same information using the Range-Energy curves for protons of Rogozinski. The result is negative for the radiative hypothesis that is unable to produce the Shroud Body Image. Therefore, to investigate the above unknown process of formation, it is necessary to think about another one. 展开更多
关键词 Hypothesis Radiative protons in the Matter Energy Lost by protons I(z) Correlations Comparison
下载PDF
Structure of the Quarks and a New Model of Protons and Neutrons: Answer to Some Open Questions
2
作者 Ágnes Cziráki 《Natural Science》 CAS 2023年第1期11-18,共8页
The described structural model tries to answer some open questions such as: Why do quarks not exist in the open state? Where are the antiparticles from the Big Bang?
关键词 Structure of Quarks New Model proton Neutron Open Questions
下载PDF
Effects of proton pump inhibitors on inflammatory bowel disease:An updated review 被引量:2
3
作者 Yu Liang Zhen Meng +1 位作者 Xue-Li Ding Man Jiang 《World Journal of Gastroenterology》 SCIE CAS 2024年第21期2751-2762,共12页
Inflammatory bowel disease(IBD)is believed to be caused by various factors,including abnormalities in disease susceptibility genes,environmental factors,immune factors,and intestinal bacteria.Proton pump inhibitors(PP... Inflammatory bowel disease(IBD)is believed to be caused by various factors,including abnormalities in disease susceptibility genes,environmental factors,immune factors,and intestinal bacteria.Proton pump inhibitors(PPIs)are the primary drugs used to treat acid-related diseases.They are also commonly prescribed to patients with IBD.Recent studies have suggested a potential association between the use of certain medications,such as PPIs,and the occurrence and progression of IBD.In this review,we summarize the potential impact of PPIs on IBD and analyze the underlying mechanisms.Our findings may provide insights for conducting further investigations into the effects of PPIs on IBD and serve as an important reminder for physicians to exercise caution when prescribing PPIs to patients with IBD. 展开更多
关键词 Drug safety proton pump inhibitor Inflammatory bowel disease Ulcerative colitis Crohn’s disease
下载PDF
Spatial and spectral measurement of laser-driven protons through radioactivation
4
作者 Yin‑Ren Shou Xue‑Zhi Wu +9 位作者 Gwang‑Eun Ahn Seung Yeon Kim Seong Hoon Kim Hwang Woon Lee Jin Woo Yoon Jae Hee Sung Seong Ku Lee Xue‑Qing Yan Il Woo Choi Chang Hee Nam 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期30-39,共10页
The simultaneous measurement of the spatial profile and spectrum of laser-accelerated protons is important for further optimization of the beam qualities and applications.We report a detailed study regarding the under... The simultaneous measurement of the spatial profile and spectrum of laser-accelerated protons is important for further optimization of the beam qualities and applications.We report a detailed study regarding the underlying physics and regular procedure of such a measurement through the radioactivation of a stack composed of aluminum,copper,and CR-39 plates as well as radiochromic films(RCFs).After being radioactivated,the copper plates are placed on imaging plates(IPs)to detect the positrons emitted by the reaction products through contact imaging.The spectrum and energy-dependent spatial profile of the protons are then obtained from the IPs and confirmed by the measured ones from the RCFs and CR-39 plates.We also discuss the detection range,influence of electrons,radiation safety,and spatial resolution of this measurement.Finally,insights regarding the extension of the current method to online measurements and dynamic proton imaging are also provided. 展开更多
关键词 Laser-driven proton acceleration proton-induced nuclear reaction Radioactivation measurement Contact imaging
下载PDF
Assessing high-energy x-ray and proton irradiation effects on electrical properties of P-GaN and N-GaN thin films
5
作者 钟傲雪 王磊 +6 位作者 唐蕴 杨永涛 王进进 朱慧平 吴真平 唐为华 李博 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期443-447,共5页
The effects of ionizing and displacement irradiation of high-energy x-ray and 2-MeV proton on GaN thin films were investigated and compared in this study.The electrical properties of both P-GaN and N-GaN,separated fro... The effects of ionizing and displacement irradiation of high-energy x-ray and 2-MeV proton on GaN thin films were investigated and compared in this study.The electrical properties of both P-GaN and N-GaN,separated from power devices,were gauged for fundamental analysis.It was found that the electrical properties of P-GaN were improved as a consequence of the disruption of the Mg-H bond induced by high-dose x-ray irradiation,as indicated by the Hall and circular transmission line model.Specifically,under a 100-Mrad(Si)x-ray dose,the specific contact resistance pc of P-GaN decreased by 30%,and the hole carrier concentration increased significantly.Additionally,the atom displacement damage effect of a 2-MeV proton of 1×10^(13)p/cm^(2)led to a significant degradation of the electrical properties of P-GaN,while those of N-GaN remained unchanged.P-GaN was found to be more sensitive to irradiation than N-GaN thin film.The effectiveness of x-ray irradiation in enhancing the electrical properties of P-GaN thin films was demonstrated in this study. 展开更多
关键词 x-ray radiation proton radiation GAN circular transmission line model(CTLM)
下载PDF
In-situ coating and surface partial protonation co-promoting performance of single-crystal nickel-rich cathode in all-solid-state batteries 被引量:1
6
作者 Maoyi Yi Jie Li +5 位作者 Mengran Wang Xinming Fan Bo Hong Zhian Zhang Aonan Wang Yanqing Lai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期137-143,I0005,共8页
The poor electrochemical performance of all-solid-state batteries(ASSBs),which is assemblied by Ni-rich cathode and poly(ethylene oxide)(PEO)-based electrolytes,can be attributed to unstable cathodic interface and poo... The poor electrochemical performance of all-solid-state batteries(ASSBs),which is assemblied by Ni-rich cathode and poly(ethylene oxide)(PEO)-based electrolytes,can be attributed to unstable cathodic interface and poor crystal structure stability of Ni-rich cathode.Several coating strategies are previously employed to enhance the stability of the cathodic interface and crystal structure for Ni-rich cathode.However,these methods can hardly achieve simplicity and high efficiency simultaneously.In this work,polyacrylic acid(PAA)replaced traditional PVDF as a binder for cathode,which can achieve a uniform PAA-Li(LixPAA(0<x≤1))coating layer on the surface of single-crystal LiNi_(0.83)Co_(0.12)Mn_(0.05)O_(2)(SC-NCM83)due to H^(+)/Li^(+)exchange reaction during the initial charging-discharging process.The formation of PAA-Li coating layer on cathode can promote interfacial Li^(+)transport and enhance the stability of the cathodic interface.Furthermore,the partially-protonated surface of SC-NCM83 casued by H^(+)/Li^(+)exchange reaction can restrict Ni ions transport to enhance the crystal structure stability.The proposed SC-NCM83-PAA exhibits superior cycling performance with a retention of 92%compared with that(57.3%)of SC-NCM83-polyvinylidene difluoride(PVDF)after 200 cycles.This work provides a practical strategy to construct high-performance cathodes for ASSBs. 展开更多
关键词 Single-crystal LiNi_(0.83)Co_(0.12)Mn_(0.05)O_(2) In-situ coating PAA-Li Partial protonation
下载PDF
Tackling the proton limit under industrial electrochemical CO_(2)reduction by a local proton shuttle
7
作者 Tianye Shao Kang Yang +4 位作者 Sheng Chen Min Zheng Ying Zhang Qiang Li Jingjing Duan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期233-243,共11页
Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In th... Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically. 展开更多
关键词 industrial CO_(2)electroreduction proton donor proton pool proton shuttle proton transport mechanism
下载PDF
Correlation between hydration properties and electrochemical performances on Ln cation size effect in layered perovskite for protonic ceramic fuel cells
8
作者 Inhyeok Cho Jiwon Yun +4 位作者 Boseok Seong Junseok Kim Sun Hee Choi Ho-Il Ji Sihyuk Choi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期1-9,I0001,共10页
PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula... PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF < Nd BSCF < Gd BSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated. 展开更多
关键词 protonic ceramic fuel cell Cathode Triple ionic and electronic conductor Hydration property proton uptake Gibbs free energy
下载PDF
Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype
9
作者 Yi-Xing Lu Wen-Cheng Fang +1 位作者 Yu-Sen Guo Zhen-Tang Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期45-58,共14页
Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact pro... Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step. 展开更多
关键词 Compact proton injector RFQ IH-DTL High gradient Tuning
下载PDF
Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy
10
作者 Xing-Yue Ruan Xiu-Fang Li +4 位作者 Meng-Ya Guo Mei Chen Ming Lv Rui Li Zhi-Ling Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期89-100,共12页
Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therap... Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future. 展开更多
关键词 proton therapy Cone-beam CT CBAM-U-Net γ-index
下载PDF
Molecular-level proton acceptor boosts oxygen evolution catalysis to enable efficient industrial-scale water splitting
11
作者 Yaobin Wang Qian Lu +7 位作者 Xinlei Ge Feng Li Le Chen Zhihui Zhang Zhengping Fu Yalin Lu Yang Song Yunfei Bu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期344-355,共12页
Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be efficient.Herein,we propose a molecular-level proton acceptor strategy... Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be efficient.Herein,we propose a molecular-level proton acceptor strategy to produce an efficient OER catalyst that can boost industrial-scale water splitting.Molecular-level phosphate(-PO_(4))group is introduced to modify the surface of PrBa_(0.5)Ca_(0.5)Co_(2)O_(5)+δ(PBCC).The achieved catalyst(PO_(4)-PBCC)exhibits significantly enhanced catalytic performance in alkaline media.Based on the X-ray absorption spectroscopy results and density functional theory(DFT)calculations,the PO_(4)on the surface,which is regarded as the Lewis base,is the key factor to overcome the kinetic limitation of the proton transfer process during the OER.The use of the catalyst in a membrane electrode assembly(MEA)is further evaluated for industrial-scale water splitting,and it only needs a low voltage of 1.66 V to achieve a large current density of 1 A cm^(-2).This work provides a new molecular-level strategy to develop highly efficient OER electrocatalysts for industrial applications. 展开更多
关键词 Oxygen evolution reaction NANOFIBER Water splitting proton acceptor PEROVSKITE
下载PDF
Analysis of the Effect of Radiation Defects by Low-energy Protons on Electrophysical Properties of Silicon N^(+)-P-P^(+) Structure
12
作者 Bogatov N.M. Grigoryan L.R. +1 位作者 Kovaenko M.S. Voodin V.S. 《Semiconductor Science and Information Devices》 2023年第1期18-25,共8页
Nowadays,radiation engineering is a promising direction in the creation of semiconductor devices.The proton irradiation is used to controllably change the optical,electrical,recombination,mechanical and structural pro... Nowadays,radiation engineering is a promising direction in the creation of semiconductor devices.The proton irradiation is used to controllably change the optical,electrical,recombination,mechanical and structural properties of the semiconductors.Low-energy protons make it possible to purposefully change material properties near the surface where the n^(+)-p junction is located.In this paper,the impact of low-energy protons on the electro physical parameters of n+-p-p+silicon photoelectric converters(SPC)is analyzed.The current-voltage characteristics and switching time of these SPCs are measured.The switching time is determined using rectangular bipolar voltage pulses with an amplitude of 10 mV,a frequency of 200 kHz,or a frequency of 1 MHz.A theoretical and experimental analysis of the obtained results is performed.The comparison of experimental data with the results of calculations shows that protons with an energy of 180 keV and a dose of 10×15 cm^(-2) create two regions in the space charge region of the n^(+)-p junction with different switching times of 4.2×10^(-7) s and 5.5×10^(-8) s.SPC frequency characteristics have been improved by reducing the effective lifetime by 5-10 times.This effect can be used to create high-speed photodiodes with an operating modulation frequency of 18 MHz. 展开更多
关键词 SILICON n+-p junction LIFETIME proton Pulse characteristic
下载PDF
Overlapping approach Proton Pump Inhibitors/Nux vomica-Heel as new intervention for gastro-esophageal reflux management:Delphi consensus study
13
作者 Edda Battaglia Luciano Bertolusso +2 位作者 Marco Del Prete Marco Monzani Marco Astegiano 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2467-2478,共12页
BACKGROUND Gastro-esophageal reflux disease(GERD)may affect the upper digestive tract;up to 20%of population in Western nations are affected by GERD.Antacids,histamine H2-receptor antagonists,and Proton Pump Inhibitor... BACKGROUND Gastro-esophageal reflux disease(GERD)may affect the upper digestive tract;up to 20%of population in Western nations are affected by GERD.Antacids,histamine H2-receptor antagonists,and Proton Pump Inhibitors(PPIs)are considered the referring medications for GERD.Nevertheless,PPIs must be managed carefully because their use,especially chronic,could be linked with some adverse effects.An effective and safe alternative pharmacological tool for GERD is needed.After the identification of potentially new medications to flank PPIs,it is mandatory to revise and improve good clinical practices even through a consensus process.AIM To optimize diagnosis and treatment guidelines for GERD through a consensus based on Delphi method.METHODS The availability of clinical studies describing the action of the multicomponent/multitarget medication Nux vomica-Heel,subject of the consensus,is the basic prerequisite for the consensus itself.A modified Delphi process was used to reach a consensus among a panel of Italian GERD specialists on the overlapping approach PPIs/Nux vomica-Heel as a new intervention model for the management of GERD.The Voting Consensus group was composed of 49 Italian Medical Doctors with different specializations:Gastroenterology,otolaryngology,geriatrics,and general medicine.A scientific committee analyzed the literature,determined areas that required investigation(in agreement with the multiple-choice questionnaire results),and identified two topics of interest:(1)GERD disease;and(2)GERD treatment.Statements for each of these topics were then formulated and validated.The Delphi process involved two rounds of questioning submitted to the panel experts using an online platform.RESULTS According to their routinary GERD practice and current clinical evidence,the panel members provided feedback to each questionnaire statement.The experts evaluated 15 statements and reached consensus on all 15.The statements regarding the GERD disease showed high levels of agreement,with consensus ranging from 70%to 92%.The statements regarding the GERD treatment also showed very high levels of agreement,with consensus ranging from 90%to 100%.This Delphi process was able to reach consensus among physicians in relevant aspects of GERD management,such as the adoption of a new approach to treat patients with GERD based on the overlapping between PPIs and Nux vomica-Heel.The consensus was unanimous among the physicians with different specializations,underlying the uniqueness of the agreement reached to identify in the overlapping approach between PPIs and Nux vomica-Heel a new intervention model for GERD management.The results support that an effective approach to deprescribe PPIs through a progressive decalage timetable(reducing PPIs administration to as-needed use),should be considered.CONCLUSION Nux vomica-Heel appears to be a valid opportunity for GERD treatment to favor the deprescription of PPIs and to maintain low disease activity together with the symptomatology remission. 展开更多
关键词 Gastro-esophageal reflux disease proton Pump Inhibitors CONSENSUS Nux vomica-Heel OVERLAPPING Decalage
下载PDF
Solid-state NMR of the retinal protonated Schiff base in microbial rhodopsins
14
作者 Sari Kumagai Izuru Kawamura 《Magnetic Resonance Letters》 2024年第3期11-18,共8页
Rhodopsin is a seven-helical transmembrane protein with a retinal chromophore covalently bound to a conserved lysine in helix G via a retinal protonated Schiff base(RPSB).Microbial rhodopsins absorb light through chro... Rhodopsin is a seven-helical transmembrane protein with a retinal chromophore covalently bound to a conserved lysine in helix G via a retinal protonated Schiff base(RPSB).Microbial rhodopsins absorb light through chromophore and play a fundamental role in optogenetics.Numerous microbial rhodopsins have been discovered,contributing to diverse functions and colors.Solid-state NMR spectroscopy has been instrumental in elucidating the conformation of chromophores and the three-dimensional structure of microbial rhodopsins.This review focuses on the 15N chemical shift values of RPSB and summarizes recent progress in the field.We displayed the correlation between the 15N isotropic chemical shift values of RPSB and the maximum absorption wavelength of rhodopsin using solid-state NMR spectroscopy. 展开更多
关键词 Membrane proteins Microbial rhodopsin RETINAL Solid-state NMR protonated Schiff base
下载PDF
Rational Design of Ruddlesden-Popper Perovskite Ferrites as Air Electrode for Highly Active and Durable Reversible Protonic Ceramic Cells
15
作者 Na Yu Idris Temitope Bello +4 位作者 Xi Chen Tong Liu Zheng Li Yufei Song Meng Ni 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期308-324,共17页
Reversible protonic ceramic cells(RePCCs)hold promise for efficient energy storage,but their practicality is hindered by a lack of high-performance air electrode materials.Ruddlesden-Popper perovskite Sr_(3)Fe_(2)O_(7... Reversible protonic ceramic cells(RePCCs)hold promise for efficient energy storage,but their practicality is hindered by a lack of high-performance air electrode materials.Ruddlesden-Popper perovskite Sr_(3)Fe_(2)O_(7−δ)(SF)exhibits superior proton uptake and rapid ionic conduction,boosting activity.However,excessive proton uptake during RePCC operation degrades SF’s crystal structure,impacting durability.This study introduces a novel A/B-sites co-substitution strategy for modifying air electrodes,incorporating Sr-deficiency and Nb-substitution to create Sr_(2.8)Fe_(1.8)Nb_(0.2)O_(7−δ)(D-SFN).Nb stabilizes SF’s crystal,curbing excessive phase formation,and Sr-deficiency boosts oxygen vacancy concentration,optimizing oxygen transport.The D-SFN electrode demonstrates outstanding activity and durability,achieving a peak power density of 596 mW cm^(−2)in fuel cell mode and a current density of−1.19 A cm^(−2)in electrolysis mode at 1.3 V,650℃,with excellent cycling durability.This approach holds the potential for advancing robust and efficient air electrodes in RePCCs for renewable energy storage. 展开更多
关键词 Reversible protonic ceramic cells Air electrode Ruddlesden-Popper perovskite HYDRATION Oxygen reduction reaction
下载PDF
Effects of baffle position in serpentine flow channel on the performance of proton exchange membrane fuel cells
16
作者 Guodong Xia Xiaoya Zhang Dandan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期250-262,共13页
This study used a three-dimensional numerical model of a proton exchange membrane fuel cell with five types of channels:a smooth channel(Case 1);eight rectangular baffles were arranged in the upstream(Case 2),midstrea... This study used a three-dimensional numerical model of a proton exchange membrane fuel cell with five types of channels:a smooth channel(Case 1);eight rectangular baffles were arranged in the upstream(Case 2),midstream(Case 3),downstream(Case 4),and the entire cathode flow channel(Case 5)to study the effects of baffle position on mass transport,power density,net power,etc.Moreover,the effects of back pressure and humidity on the voltage were investigated.Results showed that compared to smooth channels,the oxygen and water transport facilitation at the diffusion layer-channel interface were added 11.53%-20.60%and 7.81%-9.80%at 1.68 A·cm^(-2)by adding baffles.The closer the baffles were to upstream,the higher the total oxygen flux,but the lower the flux uniformity the worse the water removal.The oxygen flux of upstream baffles was 8.14%higher than that of downstream baffles,but oxygen flux uniformity decreased by 18.96%at 1.68 A·cm^(-2).The order of water removal and voltage improvement was Case 4>Case 5>Case 3>Case 2>Case 1.Net power of Case 4 was 9.87%higher than that of the smooth channel.To the Case 4,when the cell worked under low back pressure or high humidity,the voltage increments were higher.The potential increment for the back pressure of 0 atm was 0.9%higher than that of 2 atm(1 atm=101.325 kPa).The potential increment for the humidity of 100%was 7.89%higher than that of 50%. 展开更多
关键词 proton exchange membrane fuel cell Baffle position Mass transfer Net power UNIFORMITY Voltage increment
下载PDF
Performance Degradation Prediction of Proton Exchange Membrane Fuel Cell Based on CEEMDAN-KPCA and DA-GRU Networks 被引量:1
17
作者 Tingwei Zhao Juan Wang +2 位作者 Jiangxuan Che Yingjie Bian Tianyu Chen 《Instrumentation》 2024年第1期51-61,共11页
In order to improve the performance degradation prediction accuracy of proton exchange membrane fuel cell(PEMFC),a fusion prediction method(CKDG)based on adaptive noise complete ensemble empirical mode decomposition(C... In order to improve the performance degradation prediction accuracy of proton exchange membrane fuel cell(PEMFC),a fusion prediction method(CKDG)based on adaptive noise complete ensemble empirical mode decomposition(CEEMDAN),kernel principal component analysis(KPCA)and dual attention mechanism gated recurrent unit neural network(DA-GRU)was proposed.CEEMDAN and KPCA were used to extract the input feature data sequence,reduce the influence of random factors,and capture essential feature components to reduce the model complexity.The DA-GRU network helps to learn the feature mapping relationship of data in long time series and predict the changing trend of performance degradation data more accurately.The actual aging experimental data verify the performance of the CKDG method.The results show that under the steady-state condition of 20%training data prediction,the CKDA method can reduce the root mean square error(RMSE)by 52.7%and 34.6%,respectively,compared with the traditional LSTM and GRU neural networks.Compared with the simple DA-GRU network,RMSE is reduced by 15%,and the degree of over-fitting is reduced,which has higher accuracy.It also shows excellent prediction performance under the dynamic condition data set and has good universality. 展开更多
关键词 proton exchange membrane fuel cell dual-attention gated recurrent unit data-driven model time series prediction
下载PDF
Feasibility of medical radioisotope production based on the proton beams at China Spallation Neutron Source
18
作者 Bing Jiang Bin-Bin Tian +1 位作者 Han-Tao Jing Qi-Fan Dong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期26-39,共14页
The utilization of a proton beam from the China Spallation Neutron Source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high energy.The medical isotope production based ... The utilization of a proton beam from the China Spallation Neutron Source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high energy.The medical isotope production based on the proton beam at the CSNS is significant for the development of future radiopharmaceuticals,particularly for theα-emitting radiopharmaceu-ticals.The production yield and activity of typical medical isotopes were estimated using the FLUKA simulation.The results indicate that the 300-MeV proton beam with a power of 100 kW at CSNS-II is highly suitable for proof-of-principle studies of most medical radioisotopes.In particular,this proton beam offers tremendous advantages for the large-scale production of alpha radioisotopes,such as 225Ac,whose theoretical production yield can reach approximately 57 Ci/week.Based on these results,we provide perspectives on the use of CSNS proton beams to produce radioisotopes for medical applications. 展开更多
关键词 CSNS proton beam Medical isotope production α-Emitting radionuclides Nuclidic purity analysis
下载PDF
Al^(3+) doped CeO_(2) for proton conducting fuel cells
19
作者 Sarfraz Shahzad Rasool +6 位作者 Muhammad Khalid MAKYousaf Shah Bin Zhu Jung-Sik Kim Muhammad Imran Asghar Nabeela Akbar Wenjing Dong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2253-2262,共10页
Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)practically.The cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and ... Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)practically.The cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and electrochemical properties of CeO_(2).Lattice oxygen vacancies are induced in CeO_(2) by a general doping concept that enables fast ionic conduction at low-temperature ranges(300-500℃)for PCFCs.Rietveld refinement of the X-ray diffraction(XRD)patterns established the pure cubic fluorite structure of Al-doped CeO_(2)(ADC)samples and confirmed Al ions’fruitful integration in the CeO_(2) lattice.The electronic structure of the alumina-doped ceria of the materials(10ADC,20ADC,and 30ADC)has been investigated.As a result,it was found that the best composition of 30ADC-based electrolytes induced maximum lattice oxygen vacancies.The corresponding PCFC exhibited a maximum power output of 923 mW/cm^(2)at 500℃.Moreover,the investigation proves the proton-conducting ability of alumina-doped ceria-based fuel cells by using an oxide ion-blocking layer. 展开更多
关键词 proton ceramic fuel cells oxygen vacancies higher fuel cell performance DOPING fast ions transportation
下载PDF
Moisture‑Electric–Moisture‑Sensitive Heterostructure Triggered Proton Hopping for Quality‑Enhancing Moist‑Electric Generator
20
作者 Ya’nan Yang Jiaqi Wang +11 位作者 Zhe Wang Changxiang Shao Yuyang Han Ying Wang Xiaoting Liu Xiaotong Sun Liru Wang Yuanyuan Li Qiang Guo Wenpeng Wu Nan Chen Liangti Qu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期351-366,共16页
Moisture-enabled electricity(ME)is a method of converting the potential energy of water in the external environment into electrical energy through the interaction of functional materials with water molecules and can b... Moisture-enabled electricity(ME)is a method of converting the potential energy of water in the external environment into electrical energy through the interaction of functional materials with water molecules and can be directly applied to energy harvesting and signal expression.However,ME can be unreliable in numerous applications due to its sluggish response to moisture,thus sacrificing the value of fast energy harvesting and highly accurate information representation.Here,by constructing a moisture-electric-moisture-sensitive(ME-MS)heterostructure,we develop an efficient ME generator with ultra-fast electric response to moisture achieved by triggering Grotthuss protons hopping in the sensitized ZnO,which modulates the heterostructure built-in interfacial potential,enables quick response(0.435 s),an unprecedented ultra-fast response rate of 972.4 mV s^(−1),and a durable electrical signal output for 8 h without any attenuation.Our research provides an efficient way to generate electricity and important insight for a deeper understanding of the mechanisms of moisture-generated carrier migration in ME generator,which has a more comprehensive working scene and can serve as a typical model for human health monitoring and smart medical electronics design. 展开更多
关键词 Moist-electric generators Grotthuss proton hopping Fast response Durable electrical output Personal health monitoring
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部