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Hydrogen Production from Glucose by Layered Double Oxides Photocatalysis
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作者 Moraya Alqahtani Mohammed Bahattab +2 位作者 Mohammed Alabdulsalam Issa Abaalkheel Ahmad Almater 《Advances in Chemical Engineering and Science》 2025年第1期17-30,共14页
Hydrogen (H2) production from renewable biomass resources plays a significant role in solving the shortage of fossil energy;hence, there is an interest in investigating alternative, cleaner processes. This work intend... Hydrogen (H2) production from renewable biomass resources plays a significant role in solving the shortage of fossil energy;hence, there is an interest in investigating alternative, cleaner processes. This work intends to study the photocatalytic production of hydrogen from D-(+)-Glucose by using different groups of catalysts that have been prepared (M2+ = Zn, Mg and Ni) M2+/Ti4+ Al3+-LDHs (layered double hydroxides). It is then loaded Pd on the catalyst, and the effect of the composite catalyst, layered double hydroxides, is measured. After calcining, the catalyst for the conversion of Layered Double Hydroxides (LDHs) to Layered Double Oxides (LDOs) is used to produce hydrogen gas from glucose. Photocatalytic reforming of glucose-derived compounds is an efficient method for the production of hydrogen. The purpose is to study the effect of metal ions on layered double oxide (LDO) materials by loading Pd and investigate hydrogen production from glucose. The metal cations in the layer were distributed through the preparation of the catalyst process by ion and atom scale between the layers, which were dispersed systematically, as well as the controlled component catalysis. This process shows that ZnTiAl-LDO had the best effect as a catalyst in producing hydrogen compared to NiTiAl-LDO and MgTiAl-LDO. 展开更多
关键词 PHOTOCATALYSIS Hydrogen Production Layered double Oxides (LDO) D-(+)-Glucose
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A blockchain-based privacy-preserving and collusion-resistant scheme(PPCR)for double auctions
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作者 Xuedan Jia Liangmin Wang +2 位作者 Ke Cheng Pujie Jing Xiangmei Song 《Digital Communications and Networks》 2025年第1期116-125,共10页
Electronic auctions(e-auctions)remove the physical limitations of traditional auctions and bring this mechanism to the general public.However,most e-auction schemes involve a trusted auctioneer,which is not always cre... Electronic auctions(e-auctions)remove the physical limitations of traditional auctions and bring this mechanism to the general public.However,most e-auction schemes involve a trusted auctioneer,which is not always credible in practice.Some studies have applied cryptography tools to solve this problem by distributing trust,but they ignore the existence of collusion.In this paper,a blockchain-based Privacy-Preserving and Collusion-Resistant scheme(PPCR)for double auctions is proposed by employing both cryptography and blockchain technology,which is the first decentralized and collusion-resistant double auction scheme that guarantees bidder anonymity and bid privacy.A two-server-based auction framework is designed to support off-chain allocation with privacy preservation and on-chain dispute resolution for collusion resistance.A Dispute Resolution agreement(DR)is provided to the auctioneer to prove that they have conducted the auction correctly and the result is fair and correct.In addition,a Concise Dispute Resolution protocol(CDR)is designed to handle situations where the number of accused winners is small,significantly reducing the computation cost of dispute resolution.Extensive experimental results confirm that PPCR can indeed achieve efficient collusion resistance and verifiability of auction results with low on-chain and off-chain computational overhead. 展开更多
关键词 Privacy protection Collusion resistance Secure protocol Blockchain-based double auction Dispute resolution
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Research on Development Strategies for“Double First-Class”Construction of Subject Service in University Libraries
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作者 Haixin Liu Liping Liu Yanan Zhang 《Journal of Contemporary Educational Research》 2025年第1期25-31,共7页
This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”c... This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”construction and university library subject services,the study analyzes the current state of subject services,including resource development,service models,and team building.Drawing on domestic and international case studies,the paper proposes a series of targeted and practical strategies to enhance the quality of subject services in university libraries,thereby providing robust support for the advancement of the“double first-class”initiative. 展开更多
关键词 double first-class”construction University library Subject service Development strategy
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Free vibration and transient response of double curved beams connected by intermediate straight beams
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作者 R.A.JAFARI-TALOOKOLAEI H.GHANDVAR +2 位作者 E.JUMAEV S.KHATIR T.CUONG-LE 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期37-62,共26页
This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FG... This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP)materials.The strain potential and kinetic energies of each beam along with the work done by the external force are calculated.Additionally,a higher-order beam element is introduced to derive stiffness and mass matrices,along with the force vector.The curved and straight beams are discretized,and their assembled stiffness,mass matrices,and force vectors,are obtained.Continuity conditions at the joints are used to derive the total matrices of the entire structure.Subsequently,the natural frequencies and transient response of the system are determined.The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS,demonstrating excellent agreement.Furthermore,a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure. 展开更多
关键词 double curved beam vibration analysis intermediate straight beam functionally graded porous(FGP)material finite element method
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基于Double-RNN模型的电力设备故障定位与检测
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作者 李光华 赵小明 何亚东 《信息技术》 2025年第3期144-150,共7页
研究设计了一个四个步骤的热故障诊断模型:数据预处理、特征提取、设备热故障识别和设备热故障定位。Double-RNN网络模型罗列出数据处理过程并对电力设备的热故障识别进行了深入研究,该模型主要由两层RNN网络构成,分别用于数据特征抽取... 研究设计了一个四个步骤的热故障诊断模型:数据预处理、特征提取、设备热故障识别和设备热故障定位。Double-RNN网络模型罗列出数据处理过程并对电力设备的热故障识别进行了深入研究,该模型主要由两层RNN网络构成,分别用于数据特征抽取和类别预测。结果显示,在平均精度上,Double-RNN为90.06%,优于其他算法,并在检测速度上表现出了优异的实时性。由此可见,Double-RNN网络控制模型在电力设备故障定位与检测方面显示出了优越的性能表现,可以在电力设备的故障定位与检测中被广泛采用。 展开更多
关键词 double-RNN 电力设备 热故障 故障检测
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Effects of Acetic Acid Bacteria (Gluconacetobacter hansenii GK-1) on Fatigue Induced by Temporary Mental Stress: A Randomized, Double-Blind, Placebo-Controlled Study
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作者 Wei Wang Mariko Oe +6 位作者 Mengwei Yuan Keiko Kuriyama Yumi Takeda Mamoru Kimura Ryosuke Matsuoka Kiichi Sugiyama Naoki Miura 《Food and Nutrition Sciences》 2025年第1期44-54,共11页
Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placeb... Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress. 展开更多
关键词 Acetic Acid Bacteria Gluconacetobacter hansenii GK-1 FATIGUE Temporary Mental Stress double-Blind Study
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基于softmax的加权Double Q-Learning算法 被引量:1
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作者 钟雨昂 袁伟伟 关东海 《计算机科学》 CSCD 北大核心 2024年第S01期46-50,共5页
强化学习作为机器学习的一个分支,用于描述和解决智能体在与环境的交互过程中,通过学习策略以达成回报最大化的问题。Q-Learning作为无模型强化学习的经典方法,存在过估计引起的最大化偏差问题,并且在环境中奖励存在噪声时表现不佳。Dou... 强化学习作为机器学习的一个分支,用于描述和解决智能体在与环境的交互过程中,通过学习策略以达成回报最大化的问题。Q-Learning作为无模型强化学习的经典方法,存在过估计引起的最大化偏差问题,并且在环境中奖励存在噪声时表现不佳。Double Q-Learning(DQL)的出现解决了过估计问题,但同时造成了低估问题。为解决以上算法的高低估问题,提出了基于softmax的加权Q-Learning算法,并将其与DQL相结合,提出了一种新的基于softmax的加权Double Q-Learning算法(WDQL-Softmax)。该算法基于加权双估计器的构造,对样本期望值进行softmax操作得到权重,使用权重估计动作价值,有效平衡对动作价值的高估和低估问题,使估计值更加接近理论值。实验结果表明,在离散动作空间中,相比于Q-Learning算法、DQL算法和WDQL算法,WDQL-Softmax算法的收敛速度更快且估计值与理论值的误差更小。 展开更多
关键词 强化学习 Q-LEARNING double Q-Learning Softmax
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基于Dueling Double DQN的交通信号控制方法
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作者 叶宝林 陈栋 +2 位作者 刘春元 陈滨 吴维敏 《计算机测量与控制》 2024年第7期154-161,共8页
为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作... 为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作-价值函数的估计值和目标值迭代运算过程进行了优化,克服基于深度强化学习DQN的交通信号控制模型存在收敛速度慢的问题;设计了一个新的Dueling Network解耦交通状态和相位动作的价值,增强Double DQN(DDQN)提取深层次特征信息的能力;基于微观仿真平台SUMO搭建了一个单交叉口模拟仿真框架和环境,开展仿真测试;仿真测试结果表明,与传统交通信号控制方法和基于深度强化学习DQN的交通信号控制方法相比,所提方法能够有效减少车辆平均等待时间、车辆平均排队长度和车辆平均停车次数,明显提升交叉口通行效率。 展开更多
关键词 交通信号控制 深度强化学习 Dueling double DQN Dueling Network
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Diagnosis of indirectly driven double shell targets with point-projection hard x-ray radiography 被引量:1
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作者 Chao Tian Minghai Yu +17 位作者 Lianqiang Shan Fengjuan Wu Bi Bi Qiangqiang Zhang Yuchi Wu Tiankui Zhang Feng Zhang Dongxiao Liu Weiwu Wang Zongqiang Yuan Siqian Yang Lei Yang Zhigang Deng Jian Teng Weimin Zhou Zongqing Zhao Yuqiu Gu Baohan Zhang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期50-62,共13页
We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on t... We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated. 展开更多
关键词 double PROJECTION POINT
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Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel 被引量:1
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作者 N.HUMNEKAR D.SRINIVASACHARYA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期563-580,共18页
The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dyn... The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dynamics in porous materials.The analytical solutions are obtained for the unidirectional and completely developed flow.Based on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is solved.The eigenvalue problem is then solved by the spectral method.Finally,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing parameters.The results show that increasing the Darcy number,the Lewis number,the Dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the flow.Besides,the flow is the most unstable when the channel is vertically oriented. 展开更多
关键词 NANOFLUID inclined channel variable viscosity linear stability double dif-fusion porous medium
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Effective multifunctional coatings with polyvinylpyrrolidone-enhanced ZIF-67 and zinc iron layered double hydroxide on microarc oxidation treated AZ31 magnesium alloy 被引量:1
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作者 Mohammad Aadil Ananda Repycha Safira +2 位作者 Arash Fattah-alhosseini Mohammad Alkaseem Mosab Kaseem 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3729-3743,共15页
Modulating metal-organic framework’s(MOF)crystallinity and size using a polymer,in conjunction with a high surface area of layered double hydroxide,yields an effective strategy for concurrently enhancing the electroc... Modulating metal-organic framework’s(MOF)crystallinity and size using a polymer,in conjunction with a high surface area of layered double hydroxide,yields an effective strategy for concurrently enhancing the electrochemical and photocatalytic performance.In this study,we present the development of an optimized nanocomposite,denoted as 0.5PVP/ZIF-67,developed on AZ31 magnesium alloy,serving as an efficient and durable multifunctional coating.This novel strategy aims to enhance the overall performance of the porous coating through the integration of microarc oxidation(MAO),ZnFe LDH backbone,and ZIF-67 formation facilitated by the addition of polyvinylpyrrolidone(PVP),resulting in a three-dimensional,highly efficient,and multifunctional material.The incorporation of 0.5 g of PVP proved to be effective in the size modulation of ZIF-67,which formed a corrosion-resistant top layer,improving the total polarization resistance(R_(p)=8.20×10^(8)).The dual functionality exhibited by this hybrid architecture positions it as a promising candidate for mitigating environmental pollution,degrading 97.93%of Rhodamine B dye in 45 min.Moreover,the sample displayed exceptional degradation efficiency(96.17%)after 5 cycles.This study illuminates the potential of nanocomposites as electrochemically stable and photocatalytically active materials,laying the foundation for the advancements of next-generation multifunctional frameworks. 展开更多
关键词 Hybrid material POLYVINYLPYRROLIDONE Metal-organic framework Layered double hydroxide Corrosion Photocatalytic degradation
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Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients 被引量:1
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作者 Yan-Fen Xu Hui-Yun Ma +4 位作者 Gui-Ling Huang Yu-Ting Zhang Xue-Yan Wang Ming-Jie Wei Xiao-Qing Pei 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期3005-3015,共11页
BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and ... BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making. 展开更多
关键词 double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging
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Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping 被引量:1
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作者 Yongchao Yao Shengjun Sun +14 位作者 Hui Zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang Bo Tang Xuping Sun Wenchuang(Walter)Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期306-312,共7页
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau... Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution. 展开更多
关键词 Ce doping NiFe layered double hydroxide Seawater oxidation Electrocatalysis Cl^(-) repulsion
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Prediction model of surrounding rock deformation in doublecontinuous-arch tunnel based on the ABC-WNN 被引量:1
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作者 Yahui Zhang 《Railway Sciences》 2024年第6期717-730,共14页
Purpose–The wavelet neural network(WNN)has the drawbacks of slow convergence speed and easy falling into local optima in data prediction.Although the artificial bee colony(ABC)algorithm has strong global optimization... Purpose–The wavelet neural network(WNN)has the drawbacks of slow convergence speed and easy falling into local optima in data prediction.Although the artificial bee colony(ABC)algorithm has strong global optimization ability and fast convergence speed,it also has the drawbacks of slow speed while finding the optimal solution and weak optimization ability in the later stage.Design/methodology/approach–This article uses an ABC algorithm to optimize the WNN and establishes an ABC-WNN analysis model.Based on the example of the Jinan Yuhan underground tunnel project,the deformation of the surrounding rock of the double-arch tunnel crossing the fault fracture zone is predicted and analyzed,and the analysis results are compared with the actual detection amount.Findings–The comparison results show that the predicted values of the ABC-WNN model have a high degree of fitting with the actual engineering data,with a maximum relative error of only 4.73%.On this basis,the results show that the statistical features of ABC-WNN are the lowest,with the errors at 0.566 and 0.573,compared with the single back propagation(BP)neural network model and WNN model.Therefore,it can be derived that the ABC-WNN model has higher prediction accuracy,better computational stability and faster convergence speed for deformation.Originality/value–This article uses firstly the ABC-WNN for the deformation analysis of double-arch tunnels.This attempt laid the foundation for artificial intelligence prediction in deformation analysis of multiarch tunnels and small clearance tunnels.It can provide a new and effective way for deformation prediction in similar projects. 展开更多
关键词 double arch tunnel Deformation prediction Artificial bee colonies Surrounding rock Wavelet neural network
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Correction to:Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,and α for the p+^(6)Li reaction
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作者 Fang-Lei Zou Xiao-Jun Sun +10 位作者 Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期139-139,共1页
Correction to:Nuclear Science and Techniques(2024)35:61 https://doi.org/10.1007/s41365-024-01421-5 In this article,the figures were wrongly numbered.The Fig.7 and 8 should have been Fig.11 and 12.The Fig.9,10,11,and 1... Correction to:Nuclear Science and Techniques(2024)35:61 https://doi.org/10.1007/s41365-024-01421-5 In this article,the figures were wrongly numbered.The Fig.7 and 8 should have been Fig.11 and 12.The Fig.9,10,11,and 12 should have been 7,8,9 and 10.The original article has been corrected. 展开更多
关键词 corrected double differential
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Defective Nickel-Iron Layered Double Hydroxide for Enhanced Photocatalytic NO Oxidation with Significant Alleviation of NO2 Production
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作者 Xiaoyu Li Xiaoshu Lv +6 位作者 Jian Pan Peng Chen Huihui Peng Yan Jiang Haifeng Gong Guangming Jiang Li’an Hou 《Engineering》 SCIE EI CAS CSCD 2024年第5期276-284,共9页
Photocatalysis offers a sustainable means for the oxidative removal of low concentrations of NOx(NO,NO2,N2O,N2O5,etc.)from the atmosphere.Layered double hydroxides(LDHs)are promising candidate photocatalysts owing to ... Photocatalysis offers a sustainable means for the oxidative removal of low concentrations of NOx(NO,NO2,N2O,N2O5,etc.)from the atmosphere.Layered double hydroxides(LDHs)are promising candidate photocatalysts owing to their unique layered and tunable chemical structures and abundant surface hydroxide(OH)moieties,which are hydroxyl radical(OH)precursors.However,the practical applications of LDHs are limited by their poor charge-separation ability and insufficient active sites.Herein,we developed a facile N_(2)H_(4)-driven etching approach to introduce dual Ni^(2+)and OHvacancies(Niv and OHv,respectively)into NiFe-LDH nanosheets(hereafter referred to as NiFe-LDH-et)to facilitate improved charge-carrier separation and active Lewis acidic site(Fe^(3+)and Ni^(2+)exposed at OHv)formation.In contrast to inert pristine LDH,NiFe-LDH-et actively removed NO under visible-light illumination.Specifically,Ni_(76)Fe_(24)-LDH-et etched with 1.50 mmol·L^(-1)N_(2)H_(4)solution removed 32.8%of the NO in continuously flowing air(NO feed concentration:500 parts per billion(ppb))under visible-light illumination,thereby outperforming most reported catalysts.Experimental and theoretical data revealed that the dual vacancies promoted the production of reactive oxygen species(O_(2)·^(-)andOH)and the adsorption of NO on the LDH.In situ spectroscopy demonstrated that NO was preferentially adsorbed at Lewis acidic sites,particularly exposed Fe^(3+)sites,converted into NO+,and subsequently oxidized to NO3without the notable formation of the more toxic intermediate NO2,thereby alleviating risks associated with its production and emission. 展开更多
关键词 Vacancie Layered double hydroxide NO+ PHOTOCATALYSIS NO removal
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Deprotonated of layered double hydroxides during electrocatalytic water oxidation for multi-cations intercalation 被引量:1
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作者 Bowen Jin Jianxiong Gao +1 位作者 Yunqi Zhang Mingfei Shao 《Smart Molecules》 2024年第2期1-14,共14页
Aqueous rechargeable batteries using abundant multi-ion cations have receivedincreasing attention in the energy storage field for their high safety and low cost.Layered double hydroxides(LDHs)possess a two-dimensional... Aqueous rechargeable batteries using abundant multi-ion cations have receivedincreasing attention in the energy storage field for their high safety and low cost.Layered double hydroxides(LDHs)possess a two-dimensional structure andexhibit great potential as cathodes for multi-ion intercalation.However,theinsufficient active sites of LDHs result in low capacities in the discharging process.Interestingly,the LDHs after the deprotonation process exhibit favorable electrochemicalperformance of multi-cation intercalation.The deprotonation process ofLDHs has been widely found in the oxygen evolution reaction and energy storagefield,where LDHs lose H in laminates and converts to deprotonatedγ-phaseMOOHs(MOOs).Herein,we take a comprehensive overview of the dynamicsstructure transformation of the deprotonation process of LDHs.Furthermore,thedevelopment of advanced aqueous battery cathode and metal battery anode basedon deprotonated LDHs for energy storage is explored and summarized.Finally,theperspective of deprotonated LDHs in the energy storage field is discussed. 展开更多
关键词 DEPROTONATION energy storage layered double hydroxides multi-ion battery
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基于改进Double-Head RCNN的无人机航拍图像小目标检测算法 被引量:5
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作者 王殿伟 胡里晨 +1 位作者 房杰 许志杰 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第7期2141-2149,共9页
为解决无人机航拍图像中小目标特征信息少且容易被噪声干扰导致现有算法漏检率和误检率高的问题,提出一种改进Double-Head Region-卷积神经网络(RCNN)的无人机航拍图像小目标检测算法。在骨干网络ResNet-50上引入Transformer和可变形卷... 为解决无人机航拍图像中小目标特征信息少且容易被噪声干扰导致现有算法漏检率和误检率高的问题,提出一种改进Double-Head Region-卷积神经网络(RCNN)的无人机航拍图像小目标检测算法。在骨干网络ResNet-50上引入Transformer和可变形卷积(DCN)模块,更有效提取小目标特征信息和语义信息;提出一种基于内容感知特征重组(CARAFE)的特征金字塔网络(FPN)结构模块,解决特征融合过程中小目标被背景噪声干扰而丢失特征信息的问题;在区域建议网络中针对小目标尺度分布特点重新设置Anchor生成尺度,进一步提升小目标检测性能。在VisDrone-DET2021数据集上的实验结果表明:所提算法能提取更具有表征能力的小目标特征信息和语义信息,对比Double-Head RCNN算法,所提算法的参数量增加了9.73×10^(6),FPS损失了0.6,但是AP、AP50和AP75分别提升了2.6%、6.2%和2.1%,APs提升了3.1%。 展开更多
关键词 小目标检测 无人机航拍图像 double-Head RCNN TRANSFORMER 内容感知特征重组
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Young's double slit interference with vortex source
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作者 段琦琳 赵鹏飞 +1 位作者 殷玉杭 陈焕阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期395-399,共5页
The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify th... The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet. 展开更多
关键词 Young's double slit vortex source inteference patterns
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Research on static characteristic of double redundance double nozzle flapper valve based on AMESim
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作者 孙亚南 LIANG Qiuhui +2 位作者 WANG Wentao YANG Guang ZHANG Wei 《High Technology Letters》 EI CAS 2024年第2期164-169,共6页
The feedback spring rod of the armature assembly is cancelled in the double redundance double nozzle flapper valve(DRDNFV),and the difficulty of valve core displacement control is increased.Therefore,this paper intend... The feedback spring rod of the armature assembly is cancelled in the double redundance double nozzle flapper valve(DRDNFV),and the difficulty of valve core displacement control is increased.Therefore,this paper intends to study the static characteristic of DRDNFV through the AMESet and AMESim simulation.It is explored under the circumstance of the fixed orifices being clogged and experimentally verified on the test bench.The results show that the pressure gain increases and the flow gain decreases with the increasing clogged degree of the fixed orifices on both sides.The zero bias increases synchronously with the increasing clogged degree of the unilateral fixed orifice.The experimental results are basically consistent with the theoretical curves and the theoretical correctness of the simulation model is effectively verified.The results can provide the theoretical reference for design,debugging,maintenance and fault diagnosis of DRDNFV. 展开更多
关键词 double redundance double nozzle flapper valve(DRDNFV) AMESet torquemotor armature assembly fault diagnosis
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