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Rare Metals 2024年第3期43卷 1048-1061页

作者： Zheng-Hua He jian.fei gao Ling-Bin Kong State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China

Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms of two electrodes in assembled symmetrical ***,there are few reports about the wide potential window materials except Bi_(2)O_(3)and VO_(2).Therefore,the MnF_(2)synthesized by solvothermal reaction was served as the electrode for *** MnF_(2)exhibited electrochemical activity in alkaline solution in three-electrode system,especially with a wide potential window from-0.8 to+0.5 V in 2 mol·L^(-1)***,the assembled MnF_(2)//MnF_(2)symmetrical HSC had a potential window of 1.5 V,and it exhibited outstanding long-cycle ***,when MnF_(2)was taken as the negative and positive respectively,the potential windows of asymmetric devices CoMoO_(4)//MnF_(2)and MnF_(2)//Activated Carbon(AC)could reach 1.3 and 1.45 V,respectively,showing excellent cycle *** work shows that MnF_(2)material has great research value in HSC,and provides a new research direction for developing high-performance devices.

关键词： Manganese fluoride Potential window Hybrid supercapacitors Electrochemical performance

Evaluating the performance and influencing factors of three portable black carbon monitors for field measurement

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Journal of Environmental Sciences 2024年第5期139卷 320-333页

作者： Liqing Wu Yicheng Shen fei Che Yuzhe Zhang jian gao Chong Wang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan Ecological Environmental Protection Grid-Based Supervision Center Jinan 250013China

Black carbon(BC)is associated with adverse human health and climate *** BC spatial distribution imperatively requires low-cost and portable *** portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field *** study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their *** monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer *** study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in *** results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),*** discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of *** study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic *** on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing *** study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.

关键词： Black carbon Aethalometer Loading artifact Performance evaluation Portable device

Wideband spectrum sensing using step-sampling based on the multipath nyquist folding receiver

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Defence Technology（防务技术） 2024年第1期31卷 523-536页

作者： Kai-lun Tian Kai-li jiang Sen Cao jian gao Ying Xiong Bin Tang Xu-ying Zhang Yan-fei Li University of Electronic Science and Technology of China Chengdu611731China China Electronics Technology Group Corporation 29th Research Institute Chengdu610036China

Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical *** Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spectrum sensing,which is subject to the complexity of processing the modulated *** this case,a multipath NYFR architecture with a step-sampling rate for the different paths is *** different numbers of digital channels for each path are designed based on the Chinese remainder theorem(CRT).Then,the detectable frequency range is divided into multiple frequency grids,and the Nyquist zone(NZ) of the input can be obtained by sensing these ***,high-precision parameter estimation is performed by utilizing the NYFR *** with the existing methods,the scheme proposed in this paper overcomes the challenge of NZ estimation,information damage,many computations,low accuracy,and high false alarm *** simulation experiments verify the effectiveness of the proposed architecture in this paper.

关键词： Wideband spectrum sensing Sub-Nyquist sampling Step-sampling Nyquist folding receiver(NYFR) Multisignal processing

Geoscience Frontiers 2023 Annual Convention

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Geoscience Frontiers 2024年第3期15卷 484-487页

作者： fei gao Lily Wang Yongqiang Yang Geoscience Frontiers Journal CenterChina University of Geosciences(Beijing)Beijing 100083China

The 2023 Geoscience Frontiers Annual Convention was held at Niigata,Japan during 7-12 October 2023,together with 2023 IAGR Annual Convention and 20th International Conference on Gondwana to *** grand event assembled over 200 participants from several countries including China,Canada,India,Italy,Japan,Netherlands,Poland,Russia,South Korea,South Africa,Sri Lanka,Vietnam,United Kingdom,and United State of America.

关键词： Canada Convention Vietnam

Effect of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral infarction

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World Journal of Psychiatry 2024年第8期14卷 1190-1198页

作者： fei-fei Liang Xiao-Xia Liu jiang-Hong Liu Yang gao jian-Guo Dai Zi-Hui Sun Department of Geriatrics Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina The Fourth Ward Zhangjiakou Infectious Disease HospitalZhangjiakou 075000Hebei ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina Department of General Medicine Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina

BACKGROUND The aging of the population has become increasingly obvious in recent years,and the incidence of cerebral infarction has shown an increasing trend annually,with high death and disability *** To analyze the effects of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral *** Between January 2020 and December 2023,we treated 98 cases of elderly acute insula,patients with cerebral infarction in the cerebral infarction acute phase(3-4 weeks)and for the course of 6 months in Montreal Cognitive Assessment Scale(MoCA)for screening of ***,58 and 40 patients were placed in the cognitive impairment group and without-cognitive impairment group,*** patients with cerebral infarction,magnetic resonance imaging was used to screen and clearly analyze the MoCA scores of two groups of patients with different infarctions,the relationship between the parts of the infarction volume,and analysis of acute insula cognitive disorder in elderly patients with cerebral RESULTS The number of patients with cognitive impairment in the basal ganglia and thalamus was significantly higher than that without cognitive impairment(P<0.05).The total infarct volume in the cognitive impairment group was higher than that in the non-cognitive impairment group,and the difference was statistically significant(P<0.05).The infarct volumes at different sites in the cognitive impairment group was higher than in the non-cognitive impairment group(P<0.05).In the cognitive impairment group,the infarct volumes in the basal ganglia,thalamus,and mixed lesions were negatively correlated with the total MoCA score,with correlation coefficients of-0.67,-0.73,and-0.77,*** In elderly patients with acute insular infarction,infarction in the basal ganglia,thalamus,and mixed lesions were more likely to lead to cognitive dysfunction than in other areas,and patients with large infarct volumes were more like

关键词： Elderly Acute insular infarction Infarction site Cognitive impairment Infarction volume

Impact of initial fluctuations and nuclear deformations in isobar collisions

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Nuclear Science and Techniques 2024年第6期35卷 155-162页

作者： jian.fei Wang Hao-Jie Xu Fu-Qiang Wang Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Science Huzhou UniversityHuzhou 313000China Strong-Coupling Physics International Research Laboratory(SPiRL) Huzhou UniversityHuzhou 313000China Department of Physics and Astronomy Purdue UniversityWest LafayetteIN 47907USA

Relativistic isobar^(96)_(44)Ru+^(96)_(44)Ru and^(96)_(40)Zr+^(96)_(40)Zrcollisions have revealed intricate differences in their nuclear size and shape,inspiring unconventional studies of nuclear structure using relativistic heavy ion *** this study,we investigate the relative differences in the mean multiplicityR_()and the secondR_(ε2)and third-order eccentricityR_(ε3)between isobar collisions using initial state Glauber *** is found that initial fluctuations and nuclear deformations have negligible effects on R_()in most central collisions,while both are important for the R_(ε2)and R_(ε3),the degree of which is sensitive to the underlying nucleonic or sub-nucleonic degree of *** features,compared to real data,may probe the particle production mechanism and the physics underlying nuclear structure.

关键词： Relativistic isobar collisions Initial fluctuations Nuclear deformation

Exhaust hood performance and its improvement technologies in industrial buildings:A literatu rereview

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Building Simulation 2024年第1期17卷 23-40页

作者： Jing Zhang jian Wang Jun gao Weimin Zhang Architectural Engineering Institute Jinhua PolytechnicJinhua 321017China Institute of HVAC Engineering Schoolof Mechanical EngineeringTongji UniversityShanghai 200092China Tongji Architectural Design(Group)Co .LtdShanghai 200092China

The pollutant control performance of exhaust hoods plays a crucial role in the indoor air quality and energy consumption of ventilation systems in industrial *** better understand the impact of local ventilation on the industrial indoor environment,this paper presents a literature review of exhaust hood performance and its improvement *** create an index for evaluating the performance of exhaust hoods,the capture velocity,capture efficiency,flow ratio of pollutant emissions and exhaust airflow and energy consumption are first introduced.A number of factors affecting exhaust hood performance are assessed such as hood type,hood opening size,exhaust rate,installation distance,pollution source emission and environmental *** to structural improvement methods,the use of active airflow is a more effective way to improve the exhaust hood *** most commonly used methods for determining the exhaust rate are the controlled speed method and the flow ratio *** use of an exhaust hood with an appropriate exhaust rate and jet parameters(for an active air-assisted hood)can effectively improve the pollutant control performance and reduce the energy consumption that would be wasted on the redundant exhaust *** more information focused on exhaust hood performance,this work suggests more effective strategies for improving indoor air quality and reducing energy consumption in industrial buildings.

关键词： industrial ventilation exhaust hood capture efficiency exhaust rate performance improvement

Seismic-induced surficial failure of cohesive slopes using three-dimensional limit analysis:A case study of the Wangjiayan landslide in Beichuan, China

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 537-545页

作者： gao Yufeng Liu Yang Geng Weijuan Zhang fei Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai UniversityNanjing 210098China Department of Civil Engineering Faculty of Civil Engineering and MechanicsJiangsu UniversityZhenjiang 212013China

A seismic-induced landslide is a common geological catastrophe that occurs in *** Wangjiayan landslide,which was triggered by the Wenchuan earthquake,is a typical case in *** Wanjiayan landslide caused many casualties and resulted in enormous property *** study constructs a simple surficial failure model based on the upper bound approach of three-dimensional(3D)limit analysis to evaluate the slope stability of the Wangjiayan case,while a traditional two-dimensional(2D)analysis is also conducted as a reference for comparison with the results of the 3D analysis.A quasi-static calculation is used to study the effect of the earthquake in terms of horizontal ground acceleration,while a parametric study is conducted to evaluate the critical cohesion of *** than employing a 3D analysis,using the 2D analysis yields an underestimation regarding the safety *** the Wangjiayan landslide,the difference in the factors of safety between the 3D and 2D analyses can reach 20%.The sliding surface morphology as determined by the 3D method is similar to actual morphology,and the parameters of both are also compared to analyze the reliability of the proposed 3D method.

关键词： landslide Wenchuan earthquake surficial failure limit analysis stability quasi-static

High Dynamic Bounding and Jumping Motion of Quadruped Robot Based on Stable Optimization Control

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Journal of Bionic Engineering 2024年第1期21卷 101-111页

作者： Sai Gu fei Meng Botao Liu Junyao gao Qiang Huang School of Mechatronical Engineering Beijing Institute of Technology100081 BeijingChina Key Laboratory of Biomimetic Robots and Systems Ministry of EducationBeijing 100081China

Aiming at the environment such as ravines and obstacles that may be encountered in the actual movement,this paper proposes a method for optimizing the bounding and jumping motion based on the ground touching force trajectory and the air motion trajectory of the quadruped *** method of optimizing the ground reaction force according to the speed of the demand and the height of the jump,and adjusting the stance and swing time according to the relationship of dynamics and momentum *** the same time,under the constraints of dynamics and energy consumption of the robot system,considering the jumping distance and height,a method for optimizing the air trajectory of bounding and jumping is *** switching and landing stability control are also ***,the experimental results show that the quadruped robot has strong bounding and jumping ability,and has achieved stable bounding movement and forward jump movement of 0.8 m.

关键词： Quadruped robot High dynamic motion control-Periodic limit cycle Trajectory optimization

A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone

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International Journal of Mining Science and Technology 2024年第4期34卷 479-489页

作者： Huiqing Liu Heping Xie fei Wu Cunbao Li Renbo gao State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China School of Resources and Safety Engineering Chongqing UniversityChongqing 400030China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy College of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these *** with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric *** employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock *** improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore *** numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute *** results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission *** methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks.

关键词： 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences