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Automatic Generation Control with Virtual Synchronous Renewables

Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 267-279页

作者： Weichao Zhang Wanxing Sheng qing duan Hanyan Huang Xiangwu yan Beijing Key Laboratory of Distribution Transform China Electric Power Research InstituteBeijing 100192China School of Electrical and Electronic Engineering North China Electric Power UniversityBaodingChina State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina IEEE

As synchronous generators(SGs)are gradually displaced by renewable energy sources(RESs),the frequency stability of power systems deteriorates because RESs,represented by utility-scale solar and wind power sources,do not provide the inertial response,primary frequency response,secondary frequency response,and tertiary frequency regulation.As a result,the remaining SGs may not be sufficient to maintain the power balance and frequency stability.The concept and control strategies of virtual synchronous generators(VSGs)enable the inverter-based wind and solar power sources to emulate the outer characteristics of traditional SGs and participate in the active power and frequency control of power systems.This paper focuses on the automatic generation control(AGC)with virtual synchronous renewables(VSRs).First,the VSR strategy that enables the RESs to participate in AGC is introduced.Second,based on the interval representation of uncertainty,the output of RES is transformed into two portions,i.e.,the dispatchable portion and the stochastic portion.In the dispatchable portion,the RESs can participate in AGC jointly with SGs.Accordingly,a security-constrained economic dispatch(SCED)model is built considering the RESs operating in VSR mode.Third,the solution strategy that employs the slack variables to acquire deterministic constraints is introduced.Finally,the proposed SCED model is solved based on the 6-bus and 39-bus systems.The results show that,compared with the maximum power point tracking(MPPT)mode,VSRs can participate in the active power and frequency control jointly with SGs,increase the maximum penetration level of RESs,and decrease the operating cost.

关键词： Automatic generation control(AGC) economic dispatch renewable energy source(RES) virtual synchronous generator(VSG)

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Numerical simulation of drop weight impact sensitivity evaluation criteria for pressed PBXs

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Defence Technology（防务技术） 2023年第1期19卷 76-90页

作者： Hong-zheng duan yan-qing Wu Kun yang Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

A thorough understanding of drop-weight impacted responses for polymer-bonded explosives(PBXs)is significant to evaluate their impact sensitivity.The characteristics of the drop-weight impacted pressed PBXs including deforming,fracturing,forming a local high-temperature region and igniting,were simulated using a coupled mechanical-thermo-chemical model integrating micro-defects evolution.A novel evaluation method for impact sensitivity is established using the relation between the input kinetic energy and the output energy due to deformation,crushing energy,local hot spot energy and ignition.The effects of impact velocity on sensitivity were analyzed and the critical local ignition impact velocity is determined as 4.0-4.5 m/s.The simulated results show that shear-crack friction heating is the dominant ignition mechanism.The region along the boundary of PBXs sample is the most hazardous regions where ignition first occur.The propagation of stress wave in PBXs causes shear-crack hotspot and bulk temperature exhibiting an approximate 45°direction evolution path,which is the main reason that dominated damage-ignition region transits from the boundary to the central of sample.

关键词： Polymer-bonded explosives(PBXs) Drop weight impact Numerical simulation Sensitivity evaluation criterion Hotspot mechanism

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Shock response of cyclotetramethylene tetranitramine(HMX)single crystal at elevated temperatures

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Defence Technology（防务技术） 2023年第3期21卷 147-163页

作者： Kai Ding Xin-Jie Wang Zhuo-Ping duan yan-qing Wu Feng-Lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

To investigate the shock response of cyclotetramethylene tetranitramine(HMX)single crystals at elevated temperatures(below the phase transition point),plate impact experiments at elevated temperatures were designed and conducted.The HMX/window interface particle velocities at temperatures of 300 K,373 K,and 423 K were measured by the velocity interferometry system for any reflector(VISAR)technique.To further analyze the related mesoscale deformation mechanisms,a nonlinear thermoelastic-viscoplastic model was developed,which considers thermal activation and phonon drag dislocation slip mechanisms.The proposed model could well reproduce the measured thermal hardening behavior of Hugoniot elastic limit(HEL)of HMX single crystals.At elevated temperatures,the reduced dislocation mobility was observed,which stems from both phonon scattering and radiative damping effects.Comparatively speaking,radiative damping contributes less than phonon scattering to thermal hardening behavior.The calibrated model was further used to predict shock response of HMX single crystals with different thicknesses at different initial temperatures.Both the stress relaxation and elastic precursor decrease with thickness are mainly due to the rapid dislocation generation.These insights shed light on the interplay between dislocation motion and dislocation generation in thermal hardening behavior,stress relaxation,and elastic precursor decay,which serves to reveal the mesoscale deformation mechanisms at elevated temperatures.

关键词： deformation elevated dislocation

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Hierarchical Cu_(3)P-based nanoarrays on nickel foam as efficient electrocatalysts for overall water splitting

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Green Energy & Environment 2022年第2期7卷 236-245页

作者： Zhuojun yang Yongxiao Tuo qing Lu Chen Chen Mengshan Liu Bingyan Liu Xuezhi duan yan Zhou Jun Zhang School of Materials Science and Engineering China University of Petroleum(East China)66 West Changjiang RoadQingdaoShandong266580China State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)66 West Changjiang RoadQingdaoShandong266580China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China

Exploring the efficient bifunctional catalysts and binder-free electrode materials for both oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)is receiving continuous interest.Herein,we report the fabrication of hierarchical copper phosphide nanoarrays(Cu_(3)P)on three-dimensional(3D)nickel foam(NF)through a template-directed synthetic strategy as electrocatalysts for overall water splitting.Specifically,the Cu_(3)P/NF electrode demonstrates a remarkably low overpotential of~331 m V to approach the current density of 50 m A cm^(-2)in the OER,and an overpotential of~115 m V to achieve-10 m A cm^(-2)current density in the HER.Meanwhile the Cu_(3)P/NF catalyst could hold a great stability for both reactions in alkaline condition,reflected in 37 h for OER and 24 h for HER of consistent galvanostatic electrolysis.As revealed by TEM,STEM and XPS characterizations,the high catalytic OER activity can be ascribed to the 3D open structure of Cu_(3)P/NF and the abundant Cu O active sites in hierarchical Cu O/Cu_(3)P/NF structure after in-situ activation.Furthermore,the overall water splitting is conducted in a two-electrode cell,which requires only a cell voltage of 1.63 V to approach 10 m A cm^(-2)with a good stability of 20 h.This protocol of Cu_(3)P/NF electrode affords a general strategy to construct hierarchically structured metal phosphides for clean energy-related application.

关键词： nickel splitting electrode

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Local administration of liposomal-based Plekhf1 gene therapy attenuates pulmonary fibrosis by modulating macrophage polarization

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Science China(Life Sciences) 2023年第11期66卷 2571-2586页

作者： Lifeng yan Chenchen Hou Juan Liu Yi Wang Chenxi Zeng Jun Yu Tianyu Zhou qing Zhou Shengzhong duan Weining Xiong Department of Respiratory and Critical Care Medicine Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Department of Pulmonary and Critical Care Medicine The Center for Biomedical ResearchTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Thoracic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Sciences and TechnologyWuhan 430030China Shanghai Key Laboratory of Tissue Engineering Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Laboratory of Oral Microbiota and Systemic Diseases Shanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai 200011China National Center for Stomatology National Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai 200011China

Idiopathic pulmonary fibrosis(IPF)is a fatal interstitial lung disease with limited therapeutic options.Macrophages,particularly alternatively activated macrophages(M2),have been recognized to contribute to the pathogenesis of pulmonary fibrosis.Therefore,targeting macrophages might be a viable therapeutic strategy for IPF.Herein,we report a potential nanomedicinebased gene therapy for IPF by modulating macrophage M2 activation.In this study,we illustrated that the levels of pleckstrin homology and FYVE domain containing 1(Plekhf1)were increased in the lungs originating from IPF patients and PF mice.Further functionality studies identified the pivotal role of Plekhf1 in macrophage M2 activation.Mechanistically,Plekhf1 was upregulated by IL-4/IL-13 stimulation,after which Plekhf1 enhanced PI3K/Akt signaling to promote the macrophage M2 program and exacerbate pulmonary fibrosis.Therefore,intratracheal administration of Plekhf1 siRNA-loaded liposomes could effectively suppress the expression of Plekhf1 in the lungs and notably protect mice against BLM-induced lung injury and fibrosis,concomitant with a significant reduction in M2 macrophage accumulation in the lungs.In conclusion,Plekhf1 may play a crucial role in the pathogenesis of pulmonary fibrosis,and Plekhf1 siRNA-loaded liposomes might be a promising therapeutic approach against pulmonary fibrosis.

关键词： idiopathic pulmonary fibrosis macrophages alternatively activated macrophages Plekhf1 liposomes

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Neuroprotective effect of ethyl acetate extract from gastrodia elata against transient focal cerebral ischemia in rats induced by middle cerebral artery occlusion

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Journal of Traditional Chinese Medicine 2015年第6期35卷 671-678页

作者： duan Xiaohua Wang Weili Liu Xiaoqing yan Hanwen Dai Rong Lin qing the Key Modern Research Laboratory for Ethno-pharmacognosy of Yunnan Higher School Yunnan University of Traditional Chinese Medicine the Department of Pharmacology Yunnan University of Traditional Chinese Medicine Center for Neuron and Disease Frontier Institute of Science and TechnologyXi'an Jiaotong University

OBJECTIVE: To investigate the protective effect of neuroprotection against transient focal cerebral ischemia of the extract from Tianma(Rhizoma Gastrodiae) and the possible mechanisms underlying the action.METHODS: Cerebral ischemia-reperfusion injury was induced through middle cerebral artery occlusion(MCAO). Adult male Sprague-Dawley rats were randomly divided into four groups: sham-operated,ischemia-reperfusion model, 102.6 mg/kg extract treated and 11.4 mg/kg extract treated groups. The extract was prepared from gastrodia elata with ethyl acetate. The effect of the extract tested on rat neurological de fi cits and Cerebral index, cerebral infarct volume, brain injury, terminal dexynucleotidyl transferase-mediated d UTP nick end labeling(TUNEL) and B-cell lymphoma-2(Bcl-2) positive cells.RESULTS: The extract was able to reduce neurological scores, cerebral index and cerebral infarction rate. The brain injury was also relieved by the extract. The results of immunofluorescence staining analysis indicated that the extract increased the expression of Bcl-2 and reduced TUNEL-positive cells significantly in the extract treated groups.CONCLUSION: These results suggested that the extract relieved ischemic injury induced by transient focal cerebral ischemia in rats, and this neuroprotective effect might be partially due to the attenuated apoptosis pathway.

关键词： Ethyl acetate Gastrodia Neuroprotec-tive agents Reperfusion injury Apoptosis

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Damage-ignition mechanism studies on modified propellant with different crosslinking density under dynamic loading

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Defence Technology（防务技术） 2023年第10期28卷 155-164页

作者： Hong-zheng duan yan-qing Wu Xiao Hou Kun yang Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081PR China The Fourth Institute of China Aerospace Science and Technology Corporation Xi'an710025PR China

The study of high-energy and low-vulnerability propellants is important for the power performance and safety of solid propellant rocket motors.The modified split Hopkinson pressure bar(SHPB)tests are performed on two kinds of propellant with different crosslinking density to study the dynamic mechanical responses and damage-ignition mechanism.SHPB apparatus is equipped with a highperformance infrared camera and high-speed camera to capture the deformation,damage-ignition feature and temperature evolution images in the impact process.The results suggested that the mechanical responses and damage-ignition mechanism of the propellants were affected by the strain rates and crosslinking density.The damage-ignition degree is more intense and the reaction occurs earlier with the increase of strain rates.For propellant 1 with higher crosslinking density,the critical ignition strain rate is 4500 s^(-1).Two kinds of propellants show different ignition mechanism,i.***.crack generation,propagation and final fracture for propellant 1 while viscous shear flow for propellant 2.Meanwhile,the SEM images also reveal the difference of damage-ignition mechanism of the two kinds of propellants.Finally,the ignition mechanism under different strain rates and critical ignition strain rate of propellants are further explained by the theoretical calculation of temperature variations.

关键词： The modified propellants Dynamic loading Mechanical property Damage-ignition mechanism Experimental and theoretical calculation

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A target lipidomics approach to investigate the acute inflammatory irritation induced by indolealkylamines from Chansu water fraction in rats

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Chinese Journal of Natural Medicines 2021年第11期19卷 856-867页

作者： yanG Xin CHEN Wu-Yue GONG yan DI Liu-qing duan Jin-Ao ZHOU Jing MA Hong-Yue Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization and Jiangsu Key Laboratory for High Technology Research of TCM FormulaeCollege of PharmacyNanjing University of Chinese MedicineNanjing 210023China Jiangsu Engineering Research Center for Efficient Delivery System of TCM Nanjing University of Chinese MedicineNanjing 210023China

Chansu has demonstrated adverse reactions in clinical settings,which is associated with its toxicity and limits its clinical applications.But there are methodological limitations for drug safety evaluation.In the current study,ultra-high performance liquid chromatography,lipidomic profiling,and molecular docking were used to systemically assess Chansu-induced acute inflammatory irritation and further identify the underlying drug targets.Compared with the EtOAc extract,Chansu water fraction containing indolealkylamines caused acute inflammatory irritation in rats,including acute pain(spontaneous raising foot reaction),and inflammation(paw edema).At the molecular level,lipids analysis revealed significantly higher levels of pro-inflammatory mediators of the COX and LOX pathways.However,anti-inflammatory mediators from the CYP 450,ALA,and DHA pathways markedly decreased after exposure to Chansu water fraction.Moreover,four indolealkylamines from Chansu showed a high theoretical affinity to a known irritation target,5-HT_(2A)R.These results suggest that Chansu-induced inflammatory irritation is related to the distinct dysregulation of inflammatory lipids,and peripheral 5-HT_(2A)R is a potential target for irritation therapy.The strategy used in this study can be a crucial approach in the safety evaluation of natural medicinal substances.

关键词： Chansu Acute inflammatory irritation Lipidomics Eicosanoids Molecular docking

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Fractional description of mechanical property evolution of soft soils during creep

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Water Science and Engineering 2013年第4期6卷 446-455页

作者： De-shun YIN yan-qing LI Hao WU Xiao-meng duan College of Mechanics and Materials Hohai University

The motion of pore water directly influences mechanical properties of soils, which are variable during creep. Accurate description of the evolution of mechanical properties of soils can help to reveal the internal behavior of pore water. Based on the idea of using the fractional order to reflect mechanical properties of soils, a fractional creep model is proposed by introducing a variable-order fractional operator, and realized on a series of creep responses in soft soils. A comparative analysis illustrates that the evolution of mechanical properties, shown through the simulated results, exactly corresponds to the motion of pore water and the solid skeleton. This demonstrates that the proposed variable-order fractional model can be employed to characterize the evolution of mechanical properties of and the pore water motion in soft soils during creep. It is observed that the fractional order from the proposed model is related to the dissipation rate of pore water pressure.

关键词： variable-order fractional model, fractional order, soil creep, evolution ofmechanical properties soft soil

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A Critical Time-Window for the Selective Induction of Hippocampal Memory Consolidation by a Brief Episode of Slow-Wave Sleep

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Neuroscience Bulletin 2018年第6期34卷 1091-1099页

作者： Yi Lu Zheng-Gang Zhu qing-qing Ma Yun-Ting Su Yong Han Xiaodong Wang Shumin duan yan-Qin Yu Department of Neurobiology Institute of NeuroscienceNational Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical NeurobiologyZhejiang University School of Medicine

Although extensively studied, the exact role of sleep in learning and memory is still not very clear. Sleep deprivation has been most frequently used to explore the effects of sleep on learning and memory, but the results from such studies are inevitably complicated by concurrent stress and distress. Furthermore, it is not clear whether there is a strict time-window between sleep and memory consolidation. In the present study we were able to induce time-locked slow-wave sleep(SWS) in mice by optogenetically stimulating GABAergic neurons in the parafacial zone(PZ), providing a direct approach to analyze the influences of SWS on learning and memory with precise time-windows. We found that SWS induced by light for 30 min immediately or 15 min after the training phase of the object-in-place task significantly prolonged the memory from 30 min to 6 h. However, induction of SWS 30 min after the training phase did not improve memory, suggesting a critical time-window between the induction of a brief episode of SWS and learning for memory consolidation.Application of a gentle touch to the mice during light stimulation to prevent SWS induction also failed to improve memory, indicating the specific role of SWS,but not the activation of PZ GABAergic neurons itself, in memory consolidation. Similar influences of light-induced SWS on memory consolidation also occurred for Y-maze spatial memory and contextual fear memory, but not for cued fear memory. SWS induction immediately before the test phase had no effect on memory performance, indicating that SWS does not affect memory retrieval. Thus, by induction of a brief-episode SWS we have revealed a critical time window for the consolidation of hippocampusdependent memory.

关键词： Parafacial zone Slow-wave sleep Memory consolidation Hippocampus Optogenetics

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