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Single event effects evaluation on convolution neural network in Xilinx 28 nm system on chip
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作者 赵旭 杜雪成 +4 位作者 熊旭 马超 杨卫涛 郑波 周超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期638-644,共7页
Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic partic... Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips. 展开更多
关键词 single event effects convolutional neural networks alpha particle system on chip fault injection
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R-I subtype single right coronary artery with congenital absence of left coronary system: A case report 被引量:1
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作者 Ya-Ping Zhou Lin-Li Wang +1 位作者 Yuan-Gang Qiu Shu-Wei Huang 《World Journal of Cardiology》 2023年第12期649-654,共6页
BACKGROUND Isolated single coronary artery is a rare congenital anomaly.R-I subtype single coronary artery is even rarer.In this subtype,a very large right coronary artery extends in the coronary sulcus to the anterio... BACKGROUND Isolated single coronary artery is a rare congenital anomaly.R-I subtype single coronary artery is even rarer.In this subtype,a very large right coronary artery extends in the coronary sulcus to the anterior base of the heart where it produces the left anterior descending coronary artery.Currently,only a few case reports are available in the literature for this anomaly.CASE SUMMARY Here,we report the case of a 62-year-old woman who presented to the cardiology clinic with decreased exercise tolerance and poor blood pressure control.The patient underwent coronary angiography(CAG)and emission computed tomography(ECT).CAG images revealed a single gigantic right coronary artery(R-I type)arising from the right coronary sinus with branches supplying the left coronary territory.The ECT results confirmed myocardial ischemia at the location of the absent left coronary artery.The ECT findings confirmed that ischemia was consistent with the vascular loss location in CAG images.In such anomalies,there is a compensatory widening of the coronary artery lumen.Medical treatment was administered,and the patient was discharged.CONCLUSION Isolated single coronary arteries are associated with ischemia and potentially fatal acute coronary events.Hence,controlling risk factors is critical. 展开更多
关键词 single coronary artery R-I type Congenital anomaly Emission computed tomography Coronary angiography Case report
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Single-atom Pt on carbon nanotubes for selective electrocatalysis 被引量:2
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作者 Samuel S.Hardisty Xiaoqian Lin +1 位作者 Anthony R.J.Kucernak David Zitoun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期63-71,共9页
Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reactio... Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox reaction.Characterizations via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the Pt.The electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the electrocatalyst.The single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating range.The selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs. 展开更多
关键词 CONFINEMENT ELECTROCATALYSIS hydrogen PLATINUM single atom catalysts
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Metal-organic framework-based single-atom electro-/ photocatalysts: Synthesis, energy applications, and opportunities 被引量:2
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作者 Munir Ahmad Jiahui Chen +10 位作者 Jianwen Liu Yan Zhang Zhongxin Song Shahzad Afzal Waseem Raza Liaqat Zeb Andleeb Mehmood Arshad Hussain Jiujun Zhang Xian-Zhu Fu Jing-Li Luo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期1-43,共43页
Single-atom catalysts(SACs)have gained substantial attention because of their exceptional catalytic properties.However,the high surface energy limits their synthesis,thus creating significant challenges for further de... Single-atom catalysts(SACs)have gained substantial attention because of their exceptional catalytic properties.However,the high surface energy limits their synthesis,thus creating significant challenges for further development.In the last few years,metal–organic frameworks(MOFs)have received significant consideration as ideal candidates for synthesizing SACs due to their tailorable chemistry,tunable morphologies,high porosity,and chemical/thermal stability.From this perspective,this review thoroughly summarizes the previously reported methods and possible future approaches for constructing MOF-based(MOF-derived-supported and MOF-supported)SACs.Then,MOF-based SAC's identification techniques are briefly assessed to understand their coordination environments,local electronic structures,spatial distributions,and catalytic/electrochemical reaction mechanisms.This review systematically highlights several photocatalytic and electrocatalytic applications of MOF-based SACs for energy conversion and storage,including hydrogen evolution reactions,oxygen evolution reactions,O_(2)/CO_(2)/N_(2) reduction reactions,fuel cells,and rechargeable batteries.Some light is also shed on the future development of this highly exciting field by highlighting the advantages and limitations of MOF-based SACs. 展开更多
关键词 carbon energy generation MOF-derived-supported MOF-supported single atoms
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Optimizing high-coordination shell of Co-based single-atom catalysts for efficient ORR and zinc-air batteries 被引量:1
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作者 Yugang Qi Qing Liang +9 位作者 Kexin Song Xinyan Zhou Meiqi Liu Wenwen Li Fuxi Liu Zhou Jiang Xu Zou Zhongjun Chen Wei Zhang Weitao Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期306-314,I0007,共10页
Atom-level modulation of the coordination environment for single-atom catalysts(SACs)is considered as an effective strategy for elevating the catalytic performance.For the MNxsite,breaking the symmetrical geometry and... Atom-level modulation of the coordination environment for single-atom catalysts(SACs)is considered as an effective strategy for elevating the catalytic performance.For the MNxsite,breaking the symmetrical geometry and charge distribution by introducing relatively weak electronegative atoms into the first/second shell is an efficient way,but it remains challenging for elucidating the underlying mechanism of interaction.Herein,a practical strategy was reported to rationally design single cobalt atoms coordinated with both phosphorus and nitrogen atoms in a hierarchically porous carbon derived from metal-organic frameworks.X-ray absorption spectrum reveals that atomically dispersed Co sites are coordinated with four N atoms in the first shell and varying numbers of P atoms in the second shell(denoted as Co-N/P-C).The prepared catalyst exhibits excellent oxygen reduction reaction(ORR)activity as well as zinc-air battery performance.The introduction of P atoms in the Co-SACs weakens the interaction between Co and N,significantly promoting the adsorption process of ^(*)OOH,resulting in the acceleration of reaction kinetics and reduction of thermodynamic barrier,responsible for the increased intrinsic activity.Our discovery provides insights into an ultimate design of single-atom catalysts with adjustable electrocatalytic activities for efficient electrochemical energy conversion. 展开更多
关键词 ELECTROCATALYTIC Oxygen reduction reaction single atom catalyst Shell coordination optimization
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Single exposure passive three-dimensional information reconstruction based on an ordinary imaging system
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作者 窦申成 刘璠 +3 位作者 李虎 姚旭日 刘雪峰 翟光杰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期446-455,共10页
Existing three-dimensional(3D) imaging technologies have issues such as requiring active illumination, multiple exposures, or coding modulation. We propose a passive single 3D imaging method based on an ordinary imagi... Existing three-dimensional(3D) imaging technologies have issues such as requiring active illumination, multiple exposures, or coding modulation. We propose a passive single 3D imaging method based on an ordinary imaging system.Using the point spread function of the imaging system to realize the non-coding measurement on the target, the full-focus images and depth information of the 3D target can be extracted from a single two-dimensional(2D) image through the compressed sensing algorithm. Simulation and experiments show that this approach can complete passive 3D imaging based on an ordinary imaging system without any coding operations. This method can achieve millimeter-level vertical resolution under single exposure conditions and has the potential for real-time dynamic 3D imaging. It improves the efficiency of 3D information detection, reduces the complexity of the imaging system, and may be of considerable value to the field of computer vision and other related applications. 展开更多
关键词 passive three-dimensional imaging single exposure point spread function compressed sensing
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Long-Term Outcomes of Systemic-to-Pulmonary Artery Shunt in Patients with Functional Single Ventricle and Heterotaxy Syndrome
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作者 Shota Kawai Takashi Kido +6 位作者 Yuta Teguri Koji Miwa Tomomitsu Kanaya Yoichiro Ishii Hisaaki Aoki Futoshi Kayatani Sanae Tsumura 《Congenital Heart Disease》 SCIE 2023年第4期399-411,共13页
Objectives: We sought to determine the long-term outcomes and mortality-associated factors after systemic-topulmonaryartery shunt (SPS) in patients with heterotaxy syndrome. Methods: We retrospectively analyzed allpat... Objectives: We sought to determine the long-term outcomes and mortality-associated factors after systemic-topulmonaryartery shunt (SPS) in patients with heterotaxy syndrome. Methods: We retrospectively analyzed allpatients with a functional single ventricle and heterotaxy syndrome who underwent SPS at our center from January2001 to April 2022. Results: This study involved 84 patients. Restrictive pulmonary blood flow requiringearly modulation was presented in 34 (40%) patients. Compared with patients without restrictive pulmonaryblood flow (N = 50 [60%]), the postnatal survival of these 34 patients was significantly lower at 10 years (log rank:p = 0.04), but the statistical significance disappeared at 20 years (log rank: p = 0.18). Among 31 patients whounderwent SPS, 11 (35%) had extracardiac total anomalous pulmonary venous connection (TAPVC). The survivalrate after SPS was 80% at 10 years. Cox regression analysis showed that extracardiac TAPVC (hazard ratio6.44, 95% confidence interval 1.23–33.7, p = 0.03) and pulmonary venous obstruction (PVO) at TAPVC repair(hazard ratio 11.2, 95% confidence interval 2.13–58.5, p = 0.004) were significantly associated with death. In25 patients who underwent bidirectional cavopulmonary shunt (BCPS), surgical interventions on the pulmonaryartery (PA) were performed after SPS in 7 of 9 patients with PA coarctation, 3 of 4 with non-confluent PAs, and4 of 12 with normal PAs. At SPS, primary central PA plasty was performed in three patients with PA coarctationand 2 with non-confluent PAs. There was no significant difference in the PA index before BCPS between patientswith and without primary central PA plasty (p = 0.49). Among 20 patients who underwent total cavopulmonaryconnection (TCPC), adverse events occurred in 7 (35%) patients, including death in 1 (5%), intervention for pulmonaryarteriovenous malformation (PAVM) in 3 (15%), and surgical intervention for PVO in 3 (15%). TheB-type natriuretic peptide concentration was significantly higher in patients with than without adverse events(p = 0.02). The adverse event-free survival rate after TCPC was 69% at 10 years. Conclusion: ExtracardiacTAPVC and PVO at TAPVC repair were significantly associated with death after SPS in patients who had heterotaxysyndrome with a single ventricle. Surgical interventions on the PA were frequently required after SPS inpatients with PA coarctation or non-confluent PAs. Although satisfactory survival was achievable after TCPC,late-onset PAVM and PVO remain concerns. 展开更多
关键词 Heterotaxy syndrome single ventricle total anomalous of pulmonary venous connection pulmonary artery coarctation
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Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System
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作者 T.J.Thomas Thangam K.Muthu Vel 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3459-3478,共20页
The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated fr... The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed. 展开更多
关键词 Improved interleaved DC-DC SEPIC converter crow search algorithm PI controller voltage source inverter PV array single phase grid
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Advances of Synergistic Electrocatalysis Between Single Atoms and Nanoparticles/Clusters
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作者 Guanyu Luo Min Song +6 位作者 Qian Zhang Lulu An Tao Shen Shuang Wang Hanyu Hu Xiao Huang Deli Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期377-412,共36页
Combining single atoms with clusters or nanoparticles is an emerging tactic to design efficient electrocatalysts.Both synergy effect and high atomic utilization of active sites in the composite catalysts result in enh... Combining single atoms with clusters or nanoparticles is an emerging tactic to design efficient electrocatalysts.Both synergy effect and high atomic utilization of active sites in the composite catalysts result in enhanced electrocatalytic performance,simultaneously provide a radical analysis of the interrelationship between structure and activity.In this review,the recent advances of single-atomic site catalysts coupled with clusters or nanoparticles are emphasized.Firstly,the synthetic strategies,characterization,dynamics and types of single atoms coupled with clusters/nanoparticles are introduced,and then the key factors controlling the structure of the composite catalysts are discussed.Next,several clean energy catalytic reactions performed over the synergistic composite catalysts are illustrated.Eventually,the encountering challenges and recommendations for the future advancement of synergistic structure in energy-transformation electrocatalysis are outlined. 展开更多
关键词 single atoms NANOPARTICLES CLUSTERS Synergistic composite catalysts Synergistic effect
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Thermodynamically induced crystal restructuring to make CsPbCl_(3) single crystal films for weak light detection
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作者 Xiyan Pan Tai An +8 位作者 Jie Sun Hua Dong Zhu Ma Guangxing Liang Yongbo Yuan Yang Li Wuqiang Wu Yong Ding Liming Ding 《Nano Research》 SCIE EI CSCD 2024年第11期9775-9783,共9页
CsPbCl_(3) perovskite is considered a highly promising material for ultraviolet (UV) photodetectors due to its exceptional thermal stability and excellent short-wavelength light response. However, its high lattice ene... CsPbCl_(3) perovskite is considered a highly promising material for ultraviolet (UV) photodetectors due to its exceptional thermal stability and excellent short-wavelength light response. However, its high lattice energy and low polarizability result in extremely low solubility in conventional solvents, making the synthesis of CsPbCl_(3) single crystals a significant challenge. In this study, we propose a novel thermodynamically induced crystal restructuring (TICR) process that can transform microcrystalline films (MCFs) into single crystal films (SCFs) within a short period. This method, for the first time, has successfully achieved the synthesis of centimeter-sized CsPbCl_(3) SCFs and the mechanism has been explored in depth using in-situ techniques. Furthermore, we report the first instance of a CsPbCl_(3) SCF UV photodiode, which exhibits a record-breaking on/off ratio of 3.32 × 10^(7) and a detectivity of up to 1.15 × 10^(14) Jones under 0 V bias. It demonstrates excellent response even under weak light conditions of 10 nW·cm^(−2) and maintains outstanding stability with almost no performance degradation after 15 months. This study provides a novel approach for the synthesis of perovskite single crystals and holds significant potential for advancing the development of high-performance optoelectronic devices. 展开更多
关键词 CsPbCl3 single crystal film crystal restructuring PHOTODIODE ultraviolet detector
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Enhancing thermodynamic stability of single-crystal Ni-rich cathode material via a synergistic dual-substitution strategy
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作者 Jixue Shen Hui Li +6 位作者 Haoyu Qi Zhan Lin Zeheng Li Chuanbo Zheng Weitong Du Hao Chen Shanqing Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期428-436,I0010,共10页
Nickel(Ni)-rich cathode materials have become promising candidates for the next-generation electrical vehicles due to their high specific capacity.However,the poor thermodynamic stability(including cyclic performance ... Nickel(Ni)-rich cathode materials have become promising candidates for the next-generation electrical vehicles due to their high specific capacity.However,the poor thermodynamic stability(including cyclic performance and safety performance or thermal stability)will restrain their wide commercial application.Herein,a single-crystal Ni-rich Li Ni_(0.83)Co_(0.12)Mn_(0.05)O_(2) cathode material is synthesized and modified by a dual-substitution strategy in which the high-valence doping element improves the structural stability by forming strong metal–oxygen binding forces,while the low-valence doping element eliminates high Li^(+)/Ni^(2+)mixing.As a result,this synergistic dual substitution can effectively suppress H2-H3 phase transition and generation of microcracks,thereby ultimately improving the thermodynamic stability of Ni-rich cathode material.Notably,the dual-doped Ni-rich cathode delivers an extremely high capacity retention of 81%after 250 cycles(vs.Li/Li+)in coin-type half cells and 87%after 1000 cycles(vs.graphite/Li^(+))in pouch-type full cells at a high temperature of 55℃.More impressively,the dual-doped sample exhibits excellent thermal stability,which demonstrates a higher thermal runaway temperature and a lower calorific value.The synergetic effects of this dual-substitution strategy pave a new pathway for addressing the critical challenges of Ni-rich cathode at high temperatures,which will significantly advance the high-energy-density and high-safety cathodes to the subsequent commercialization. 展开更多
关键词 Ni-rich cathode single crystalline Dual-substitution strategy High-temperature cathode Li-ion batteries
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Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center
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作者 Wenjing Quan Jia Shi +10 位作者 Min Zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期515-531,共17页
Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption prop... Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas detection.Specifically,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was integrated.The sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 ppb.Simulation analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for NH3.Additionally,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid interface.The sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing signal.Furthermore,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity conditions.This work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research. 展开更多
关键词 Gas sensor single atom Catalytic activation Targeted adsorption End-sealing passivation
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Application of metal-based catalysts for Fenton reaction: from homogeneous to heterogeneous, from nanocrystals to single atom
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作者 Shangkun Pei Sheng Wang +2 位作者 Yuxin Lu Xiang Li Bo Wang 《Nano Research》 SCIE EI CSCD 2024年第11期9446-9471,共26页
Nowadays, increasing emissions of hazardous chemicals cause serious environmental pollution. The advanced oxidation processes (AOPs), which produce numbers of reactive oxygen species (ROS), are one of the most widely ... Nowadays, increasing emissions of hazardous chemicals cause serious environmental pollution. The advanced oxidation processes (AOPs), which produce numbers of reactive oxygen species (ROS), are one of the most widely used technologies for degrading refractory pollutants in aqueous phase. Among these, Fenton reaction including both homogeneous and heterogeneous processes, has received increasing attention for water treatment. In this review, various nanomaterials with different size such as nanocrystals, nanoparticles (e.g., iron-based minerals, bimetallic oxides, zero-valent iron, quantum dots) and metal-based single atom catalysts (SACs) applied in homogeneous and heterogeneous Fenton reactions, as well as the corresponding catalytic mechanisms will be systematically summarized. Several factors including the morphology, chemical composition, geometric/electronic structures influence the catalytical behavior simultaneously. Here, the recent research advancement including the advantages and further challenges in homogeneous and heterogeneous Fenton system will be introduced in detail. Furthermore, developments for different nanomaterials, from nanocrystals, nanoparticles (minerals, bimetallic oxides represented by Fe-based catalysts, and nanosized zero valent iron materials) to SACs will be discussed. Some representative catalysts for Fenton reaction and their applications will be presented. In addition, commonly-used supports (e.g., graphene oxide, g-C3N4, and carbon nanotubes) and metal-organic frameworks (MOFs)/derivatives and metal-support interaction for improving Fenton-like performance will be introduced. Finally, different types of catalysts for Fenton reaction are compared and their practical application and operational costs are summarized. 展开更多
关键词 NANOCRYSTALS water purification NANOMATERIALS single atom catalysts(SACs) heterogeneous reaction
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Structure design and electrochemical properties of carbon-based single atom catalysts in energy catalysis:A review
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作者 Shuqi Li Xincheng Lu +8 位作者 Shuling Liu Jingjing Zhou Yanyan Liu Huanhuan Zhang Ruofan Shen Kang Sun Jianchun Jiang Yongfeng Wang Baojun Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期196-236,共41页
Single atom catalysts(SACs) possessing regulated electronic structure, high atom utilization, and superior catalytic efficiency have been studied in almost all fields in recent years. Carbon-based supporting SACs are ... Single atom catalysts(SACs) possessing regulated electronic structure, high atom utilization, and superior catalytic efficiency have been studied in almost all fields in recent years. Carbon-based supporting SACs are becoming popular materials because of their low cost, high electron conductivity, and controllable surface property. At the stage of catalysts preparation, the rational design of active sites is necessary for the substantial improvement of activity of catalysts. To date, the reported design strategies are mainly about synthesis mechanism and synthetic method. The level of understanding of design strategies of carbon-based single atom catalysts is requiring deep to be paved. The design strategies about manufacturing defects and coordination modulation of catalysts are presented. The design strategies are easy to carry out in the process of drawing up preparation routes. The components of carbon-based SACs can be divided into two parts: active site and carbon skeleton. In this review, the manufacture of defects and coordination modulation of two parts are introduced, respectively. The structure features and design strategies from the active sites and carbon skeletons to the overall catalysts are deeply discussed.Then, the structural design of different nano-carbon SACs is introduced systematically. The characterization of active site and carbon skeleton and the detailed mechanism of reaction process are summarized and analyzed. Next, the applications in the field of electrocatalysis for oxygen conversion and hydrogen conversion are illustrated. The relationships between the superior performance and the structure of active sites or carbon skeletons are discussed. Finally, the conclusion of this review and prospects on the abundant space for further promotion in broader fields are depicted. This review highlights the design and preparation thoughts from the parts to the whole. The detailed and systematic discussion will provide useful guidance for design of SACs for readers. 展开更多
关键词 Carbon materials Coordination chemistry Defective structure Energy catalysis single atom catalysts
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Cooperation between single atom catalyst and support to promote nitrogen electroreduction to ammonia:A theoretical insight
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作者 Wanying Guo Siyao Wang +2 位作者 Hongxia Wang Qinghai Cai Jingxiang Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期336-344,共9页
The co-catalysis between single atom catalyst(SAC)and its support has recently emerged as a promising strategy to synergistically boost the catalytic activity of some complex electrochemical reactions,encompassing mul... The co-catalysis between single atom catalyst(SAC)and its support has recently emerged as a promising strategy to synergistically boost the catalytic activity of some complex electrochemical reactions,encompassing multiple intermediates and pathways.Herein,we utilized defective BC_(3)monolayer-supported SACs as a prototype to investigate the cooperative effects of SACs and their support on the catalytic performance of the nitrogen reduction reaction(NRR)for ammonia(NH_(3))production.The results showed that these SACs can be firmly stabilized on these defective BC_(3)supports with high stability against aggregation.Furthermore,co-activation of the inert N_(2)reactant was observed in certain embedded SACs and their neighboring B atoms on certain BC3 sheets due to the noticeable charge transfer and significant N–N bond elongation.Our high-throughput screening revealed that the Mo/DV_(CC)and W/DV_(CC)exhibit superior NRR catalytic performance,characterized by a low limiting potential of−0.33 and−0.43 V,respectively,which can be further increased under acid conditions based on the constant potential method.Moreover,varying NRR catalytic activities can be attributed to the differences in the valence state of active sites.Remarkably,further microkinetic modeling analysis displayed that the turnover frequency of N_(2)–to–NH_(3)conversion on Mo/DV_(CC)is as large as 1.20×10^(−3)s^(−1)site^(−1) at 700 K and 100 bar,thus guaranteeing its ultra-fast reaction rate.Our results not only suggest promising advanced electrocatalysts for NRR but also offer an effective avenue to regulate the electrocatalytic performance via the co-catalytic metal–support interactions. 展开更多
关键词 CO-CATALYSIS single atom catalyst Nitrogen reduction DFT computations
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Preparation of single atom catalysts for high sensitive gas sensing
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作者 Xinxin He Ping Guo +7 位作者 Xuyang An Yuyang Li Jiatai Chen Xingyu Zhang Lifeng Wang Mingjin Dai Chaoliang Tan Jia Zhang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期216-248,共33页
Single atom catalysts(SACs)have garnered significant attention in the field of catalysis over the past decade due to their exceptional atom utilization efficiency and distinct physical and chemical properties.For the ... Single atom catalysts(SACs)have garnered significant attention in the field of catalysis over the past decade due to their exceptional atom utilization efficiency and distinct physical and chemical properties.For the semiconductor-based electrical gas sensor,the core is the catalysis process of target gas molecules on the sensitive materials.In this context,the SACs offer great potential for highly sensitive and selective gas sensing,however,only some of the bubbles come to the surface.To facilitate practical applications,we present a comprehensive review of the preparation strategies for SACs,with a focus on overcoming the challenges of aggregation and low loading.Extensive research efforts have been devoted to investigating the gas sensing mechanism,exploring sensitive materials,optimizing device structures,and refining signal post-processing techniques.Finally,the challenges and future perspectives on the SACs based gas sensing are presented. 展开更多
关键词 single atom catalysts PREPARATION sensing mechanism gas sensing
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Oxidation behavior of 4774DD1 Ni-based single-crystal superalloy at 980℃ in air
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作者 Yu Fang Ya-zhou Li +7 位作者 Qiang Yang Qun-gong He Xiu-fang Gong Qian Duan Hai-yang Song Fu Wang Qiong-yuan Zhang Hong Zeng 《China Foundry》 SCIE EI CAS CSCD 2024年第2期116-124,共9页
The oxidation behavior of a novel Ni-based single-crystal 4774DD1 superalloy for industrial gas turbine applications was investigated by the isothermal oxidation at 980℃ and discontinuous oxidation weight gain method... The oxidation behavior of a novel Ni-based single-crystal 4774DD1 superalloy for industrial gas turbine applications was investigated by the isothermal oxidation at 980℃ and discontinuous oxidation weight gain methods.The phase constitution and morphology of surface oxides and the characteristics of the crosssection oxide film were analyzed by XRD,SEM and EDS.Results show that the oxidation kinetics of the 4774DD1 superalloy follows the cubic law,indicating its weak oxidation resistance at this temperature.As the oxidation time increases,the composition of the oxide film evolves as following:One layer consisting of a bottom Al_(2)O_(3)sublayer and an upper(Al_(2)O_(3)+NiO)mixture sublayer after oxidized for 25 h.Then,two layers composed of an outermost small NiO discontinuous grain layer and an internal layer for 75 h.This internal layer is consisted of the bottom Al_(2)O_(3)sublayer,an intermediate narrow CrTaO_(4)sublayer,and an upper(Al_(2)O_(3)+NiO)mixture sublayer.Also two layers comprising an outermost relative continuous NiO layer with large grain size and an internal layer as the oxidation time increases to 125 h.This internal layer is composed of the upper(Al_(2)O_(3)+NiO)mixture sublayer,an intermediate continuous(CrTaO_(4)+NiWO_(4))mixture sublayer,and a bottom Al_(2)O_(3)sublayer.Finally,three layers consisting of an outermost(NiAl2O_(4)+NiCr2O_(4))mixture layer,an intermediate(CrTaO_(4)+NiWO_(4))mixture layer,and a bottom Al_(2)O_(3)layer for 200 h. 展开更多
关键词 nickel-base single crystal superalloy oxidation kinetics oxide film MICROSTRUCTURE mechanism
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Manipulating photogenerated electron flow in nickel single‐atom catalysts for photocatalytic CO_(2) reduction into tunable syngas
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作者 Yida Zhang Qingyu Wang +5 位作者 Lihui Wu Haibin Pan Chengyuan Liu Yue Lin Gongming Wang Xusheng Zheng 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期205-213,共9页
The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)signific... The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites.Herein,we demonstrate that the doping of phosphorus(P)significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO_(2) reduction into syngas.During photocatalytic CO_(2) reduction,Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85μmol gcat^(−1)h^(−1) and continuously adjustable CO/H_(2) ratios ranging from 5:1 to 1:2,which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts.Mechanistic studies reveal that P doping improves the conductivity of catalysts,which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites,facilitating the CO_(2)‐to‐syngas photoreduction process. 展开更多
关键词 carbon nitride CO_(2) photoreduction electron flow Ni single atoms SYNGAS
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Lattice strain induced by trace Pt single atoms in nickel for accelerating industrial hydrogen evolution
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作者 Rui Yao Yun Wu +4 位作者 Kaiyang Zhang Shuhui Fan Qiang Zhao Jinping Li Guang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期503-511,共9页
Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen production.Herein,w... Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen production.Herein,we present a unipolar pulsed electrodeposition(UPED) strategy to induce strain in the Ni lattice by introducing trace amounts of Pt single atoms(SAs)(0.22 wt%).The overpotential decreased by 183 mV at 10 mA cm^(-2) in 1.0 M KOH after introducing trace amounts of Pt_(SAs).The industrial electrolyzer,assembled with Pt_(SAs)Ni cathode and a commercial NiFeO_(x) anode,requires a cell voltage of 1.90 V to attain 1 A cm^(-2) of current density and remains stable for 280 h,demonstrating significant potential for practical applications.Spherical aberration corrected scanning transmission electron microscopy(AC-STEM),X-ray absorption(XAS),and geometric phase analysis(GPA) indicate that the introduction of trace amounts of Pt SAs induces tensile strain in the Ni lattice,thereby altering the local electronic structure and coordination environment around cubic Ni for enhancing the water decomposition kinetics and fundamentally changing the reaction pathway.The doping-strain strategy showcases conformational relationships that could offer new ideas to construct efficient hydrogen evolution reaction(HER) electrocatalysts for industrial hydrogen production in the future. 展开更多
关键词 Unipolar pulsed electrodeposition Pt single atoms Ni lattice Hydrogen evolution reaction H intermediates
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Cryptanalysis of efficient semi-quantum secret sharing protocol using single particles
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作者 高甘 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期254-257,共4页
In paper[Chin.Phys.B 32070308(2023)],Xing et al.proposed a semi-quantum secret sharing protocol by using single particles.We study the security of the proposed protocol and find that it is not secure,that is,the three... In paper[Chin.Phys.B 32070308(2023)],Xing et al.proposed a semi-quantum secret sharing protocol by using single particles.We study the security of the proposed protocol and find that it is not secure,that is,the three dishonest agents,Bob,Charlie and Emily can collude to obtain Alice's secret without the help of David. 展开更多
关键词 security loophole rearranging orders semi-quantum secret sharing single particles
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