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Science China Chemistry 2019年第12期62卷 1561-1575页

作者： Yuan peng Weishen yang State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Metal-organic framework nanosheets have gained great attention because of the diversified structures,tunable chemical functionalities,large surface area and ultrathin *** this review,we introduce the recent progress in the favorable applications for catalysis,sensing,energy storage and gas separation,which has significantly addressed the advantages of the nanosheets.A summary of nanosheet fabrication approaches is put forward to establish a comprehension on the origin of the MOF *** at last but not the least,we present the concerns on the challenges and opportunities of these materials from our perspectives.

关键词： metal-organic framework nanosheet catalysis sensing energy storage gas separation

Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu Guo Lanyue Zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li Yong peng Wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction

Integrated guidance and control design for missile with terminal impact angle constraint based on sliding mode control

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Journal of Systems Engineering and Electronics 2010年第4期21卷 623-628页

作者： peng Wu Ming yang Control and Simulation Center Harbin Institute of Technology Harbin 150001 E R. China

Aimed at the guidance requirements of some missiles which attack targets with terminal impact angle at the terminal point,a new integrated guidance and control design scheme based on variable structure control approach for missile with terminal impact angle constraint is ***,a mathematical model of an integrated guidance and control model in pitch plane is established,and then nonlinear transformation is employed to transform the mathematical model into a standard form suitable for sliding mode control method design.A sufficient condition for the existence of linear sliding surface is given in terms of linear matrix inequalities（LMIs）,based on which the corresponding reaching motion controller is also *** verify the effectiveness of the proposed integrated design scheme,the numerical simulation of missile is *** simulation results demonstrate that the proposed guidance and control law can guide missile to hit the target with desired impact angle and desired flight attitude angle simultaneously.

关键词： guidance terminal impact angle sliding mode control integrated guidance and control linear matrix inequality(LMI).

Editorial Special Issue on Simulation and AI

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Journal of Systems Science and Systems Engineering 2023年第3期32卷 265-266页

作者： Yijie peng Yaodong yang Center for Multi-Agent Research Institute for AIPeking UniversityBeijing 100871China Guanghua School of Management Peking UniversityBeijing 100871China

Simulation is an important area in Operations Research,Management Science and many disciplines,and it has many advantages in analyzing the performance of complex stochastic *** the last 15 years,AI has been gaining steam and fundamentally reshaped a number of current and emerging *** plays a central role in deep learning and reinforcement learning,which are the foundation of AI,and it can continue improving the AI techniques,particularly in addressing some of its bottlenecks.

关键词： has shaped continue

Diagnostics of Ellerman bombs with high-resolution spectral data

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Research in Astronomy and Astrophysics 2015年第9期15卷 1513-1524页

作者： Zhen Li Cheng Fang yang Guo peng-Fei Chen Zhi Xu Wen-da Cao School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Collaborative Innovation Center of Modern Astronomy and Space Exploration Yunnan Observatories Chinese Academy of Sciences Big Bear Solar Observatory New Jersey Institute of Technology

Ellerman bombs （EBs） are tiny brightenings often observed near sunspots. The most impressive characteristic of EB spectra is the two emission bumps in both wings of the Hα and Ca II 8542 A lines. High-resolution spectral data of three small EBs were obtained on 2013 June 6 with the largest solar telescope, the 1.6 m New Solar Telescope at the Big Bear Solar Observatory. The characteristics of these EBs are analyzed. The sizes of the EBs are in the range of 0.3＂ - 0.8＂ and their durations are only 3-5 min. Our semi-empirical atmospheric models indicate that the heating occurs around the temperature minimum region with a temperature increase of 2700- 3000 K, which is surprisingly higher than previously thought. The radiative and kinetic energies are estimated to be as high as 5 × 1025 - 3.0 × 10^26 erg despite the small size of these EBs. Observations of the magnetic field show that the EBs just appeared in a parasitic region with mixed polarities and were accompanied by mass motions. Nonlinear force-free field extrapolation reveals that the three EBs are connected with a series of magnetic field lines associated with bald patches, which strongly implies that these EBs should be produced by magnetic reconnection in the solar lower atmosphere. According to the lightcurves and the estimated magnetic reconnection rate, we propose that there is a three phase process in EBs： pre-heating, flaring and cooling phases.

关键词： Sun: chromosphere -- Sun: photosphere -- line profiles -- magnetic reconnection

Modeling and Verification of an Astronaut Handling Large-mass Payload

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 517-523页

作者： yang Aiping yang Chunxin KE peng School of Aeronautics Science and Engineering Beihang University Beijing 100191 China School of Transportation Science andEngineering Beihang University Beijing 100191 China

The experiments on astronaut motions are difficult to conduct due to the limitation and high cost of constructing or simulating the microgravity environment of space. Therefore, the method of computer simulation on astronaut extravehicular activity is broadly promoted. However, validations and verifications for these simulations stated in related literatures are incomplete such as comparing with the limits of human body movements or reconstructing a three-dimensional movement for some parts of EVA video. Novel modeling and verification methods for the task of an astronaut handling targe-mass payload during EVA were revealed. A simplified model of an astronaut was constructed, and the astronaut motion was conceived as a planar movement of a multi-body system which includes seven segments with six revolute joints in the human body sagittal plane. The inverse kinematics method was used to calculate joint angles, joint velocities, and joint accelerations in time domain. The solution of joint torques using the inverse recursive dynamics was achieved. Furthermore, a virtual model with the AdaMSTM software was developed and implemented to verify the results by adding the kinematical data calculated to joints in order to achieve the trace of the center of mass of the hand. Additionally, the joints kinematics and kinetics data with time in the virtual model were obtained and compared with the corresponding calculated data. This result indicates that the modeling methods proposed can be employed as a solid algorithm to conduct the simulation of astronaut＇s tasks in EVA, and verification using the virtual model can be easily operated and has a good accuracy. This study provides an effective and economical way of modeling and simulation for extravehicular missions.

关键词： extravehicular activity inverse kinematics inverse recursive dynamics AdaIVISTM virtual model

Prognostic factors and its predictive value in patients with metastatic spinal cancer

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World Journal of Clinical Cases 2021年第20期9卷 5470-5478页

作者： Qing-peng Gao da-Zhi yang Zheng-Bin Yuan Yu-Xia Guo Department of Spine Surgery The Second Clinical Medical College of Jinan UniversityShenzhen 518020Guangdong ProvinceChina Department of Spine Surgery Shenzhen People’s Hospital2nd Clinical Medical College of Jinan UniversityShenzhen 518020Guangdong ProvinceChina Department of Gynecology Shenzhen People’s Hospital2nd Clinical Medical College of Jinan UniversityShenzhen 518020Guangdong ProvinceChina

BACKGROUND The spine is the most common location of metastatic *** a metastatic spinal tumor depends on many factors,including patients’overall health and life *** present study was conducted to investigate prognostic factors and clinical outcomes in patients with vertebral *** To investigate prognostic factors and their predictive value in patients with metastatic spinal *** A retrospective analysis of 109 patients with metastatic spinal cancer was conducted between January 2015 and September *** prognoses and survival were analyzed,and the effects of factors such as clinical features,treatment methods,primary lesions and affected spinal segments on the prognosis of patients with metastatic spinal cancer were *** prognostic value of Frankel spinal cord injury functional classification scale,metastatic spinal cord compression(MSCC),spinal instability neoplastic score(SINS)and the revised Tokuhashi score for prediction of prognosis was explored in patients with metastatic spinal *** Age,comorbidity of metastasis from elsewhere,treatment methods,the number of spinal tumors,patient’s attitude toward tumors and Karnofsky performance scale score have an effect on the prognosis of patients(all P<0.05).With respect to classification of spinal cord injury,before operation,the proportion of grade B and grade C was higher in the group of patients who died than in the group of patients who survived,and that of grade D and grade E was lower in the group of patients who died than in the group of patients who survived(all P<0.05).At 1 mo after operation,the proportion of grade A,B and C was higher in the group of patients who died than in the group of patients who survived,and that of grade E was lower in patients in the group of patients who died than in the group of patients who survived(all P<0.05).MSCC occurred in four(14.3%)patients in the survival group and 17(21.0%)patients in the death group(P<0.05).

关键词： Metastatic spinal tumors Frankel spinal cord injury functional classification scale Metastatic spinal cord compression Spinal instability neoplastic score Revised Tokuhashi score

Stern-Geary Constant for X80 Pipeline Steel in the Presence of Different Corrosive Microorganisms

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1483-1489页

作者： Yu-peng Sun Chun-Tian yang Chun-Guang yang da-Ke Xu Qi Li Lu Yin Cheng-Shuo Qiu dan liu Ke yang College of Chemistry Liaoning UniversityShenyang 110036China Shenyang National Laboratory for Material Sciences Northeastern UniversityShenyang 110819China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The Stern-Geary constant(B value)is indispensable to measure the corrosion rate in the microbiologically influenced corrosion(MIC)*** polarization resistance(LPR)and weight loss methods were used to study the variation of B values for X80 pipeline steel in the presence of Pseudomonas aeruginosa,Acetobacter aceti and Desulfovibrio *** results showed that B values in the presence of three different bacteria were 35.60±0.55 mV,33.00±1.00 mV and 58.60±0.55 mV,respectively,suggesting that the change of corrosion system significantly affected the B values of X80 pipeline *** work further indicated that the determination of B values is necessary to accurately measure the MIC rate by LPR method.

关键词： X80 pipeline steel Stern-Geary constant Corrosion rate Microbiologically influenced corrosion Biofilm

Generalized Shape and Gauge Decoupling Load Distribution Optimization Based on IGA for Tandem Cold Mill

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Journal of Iron and Steel Research International 2009年第2期16卷 30-34页

作者： peng peng yang Quan National Engineering Research Center for Advanced Rolling Technology University of Science andTechnology Beijing Beijing 100083 China

Load distribution is the foundation of shape control and gauge control, in which it is necessary to take into account the shape control ability of TCM （tandem cold mill） for strip shape and gauge quality. First, the objective function of generalized shape and gauge decoupling load distribution optimization was established, which considered the rolling force characteristics of the first and last stands in TCM, the relative power, and the TCM shape control ability. Then, IGA （immune genetic algorithm） was used to accomplish this multi-objective load distribution optimization for TCM. After simulation and comparison with the practical load distribution strategy in one tandem cold mill, general- ized shape and gauge decoupling load distribution optimization on the basis of IGA approved good ability of optimizing shape control and gauge control simultaneously.

关键词： load distribution immune genetic algorithm shape decoupling gauge decoupling tandem cold mill

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume