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Motion-pressure coupled control and simulation of long-endurance capability for multicapsule stratospheric airships

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Chinese Journal of Aeronautics 2024年第6期37卷 137-150页

作者： Zhiguang SHI Wei huo Zongyu ZUO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Beijing Near Space Airship Technology Development Co. LtdBeijing 100070China

The current study focuses on the motion-pressure coupled control for a multicapsule stratospheric airship and transforms the path-tracking and heading-hold control of airships into guidance tracking with a time-varying weighted sum of longitudinal and lateral velocities by the definition of compound ***,an improved nonlinear predictive control method is provided to reduce the control energy consumption by the rolling optimization of controller parameters based on finite time intervals,ensuring infinite-time path-tracking ***,combined with the proposed cyclic regulation process of safe pressure between internal and external capsules,this study can fully reflect the force-thermal coupled rule of airships under the actions of atmospheric environment and maneuvering force,while evaluating the long-endurance capability of airships under the conditions of safe superheating and *** effectiveness of the motionpressure coupled controller was verified through numerical simulations,which can overcome the influence of environmental wind and achieve a tracking effect for the desired cruise path and compound *** airspeed provided during the cyclic circadian time caused the maximum superheating of the helium controlled within 30*** helium in the internal and external capsules achieved circadian *** equivalent micropore diameter of the capsule of 5 mm can achieve 55 days of long-endurance *** controller satisfies the requirements of cruise-flight application modes for multicapsule stratospheric airships with important engineering value.

关键词： Compound speed Nonlinear predictive control Cyclic pressure regulation Long-endurance capability Stratospheric airship

High performance photodegradation resistant PVA@TiO_(2)/carboxyl-PES self-healing reactive ultrafiltration membrane

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Chinese Journal of Chemical Engineering 2024年第2期66卷 31-39页

作者： Yu Liang Yuanfang Fan Zhongmin Su Mingxin huo Xia Yang Hongliang huo Chi Wang Zhi Geng College of Environment Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast ChinaMinistry of EducationNortheast Normal UniversityChangchun 130117China School of Science Hainan UniversityHaikou 570225China

The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF *** self-cleaning UF membranes can effectively alleviate the problem of membrane ***,the self-cleaning process may accelerate membrane *** these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF *** begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid ***,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF ***,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF *** establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning ***,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing *** results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing *** anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive

关键词： Ultrafiltration membrane Self-cleaning Self-healing Poly(aryl ether sulfone)

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大型旋转设备压液式自动平衡系统

机械工程学报 2023年第18期59卷 121-129页

作者：霍家骥于洪杰潘鑫江志农宾光富北京化工大学高端机械装备健康监控与自愈化北京市重点实验室北京100029 北京化工大学机电工程学院北京100029 湖南科技大学机电工程学院湘潭411201

压液式在线自动平衡系统作为一种新型的液体式自动平衡系统,具有结构简单、旋转部分无可动部件、动作环境封闭、平衡过程可逆且可停机保持等优点。相较于已有其他在线自动平衡系统,更适用于大型旋转设备领域。介绍该在线自动平衡系统的... 详细信息

压液式在线自动平衡系统作为一种新型的液体式自动平衡系统,具有结构简单、旋转部分无可动部件、动作环境封闭、平衡过程可逆且可停机保持等优点。相较于已有其他在线自动平衡系统,更适用于大型旋转设备领域。介绍该在线自动平衡系统的组成及工作原理,基于某最大直径达500 mm的转子实际结构,通过有限元仿真对转子-轴承-单/双平衡执行器系统的动力学特性进行定量分析,据此设计的平衡执行器对原转子系统的动力学特性影响在2%以内;分别进行单/双平衡执行器的抑振效果模拟仿真,振幅降低70%以上。最终在模拟试验台上,通过单面自动平衡试验将转子振幅从18.6μm降至10.6μm,验证该平衡系统的可行性和有效性;通过双面动平衡将转子振幅从17.8μm降低至4.6μm,为后续双面自动平衡研究奠定技术基础。

关键词：大型旋转设备自动平衡压液式动力学特性仿真结构优化设计

Robust Interval State Estimation for Distribution Systems Considering Pseudo-measurement Interval Prediction

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 179-188页

作者： Xu Zhang Wei Yan Meiqing huo Hui Li the School of Electrical Engineering Chongqing UniversityChongqing 400044China

Interval state estimation(ISE)can estimate state intervals of power systems according to confidence intervals of predicted pseudo-measurements,thereby analyzing the impact of uncertain pseudo-measurements on ***,predicted pseudo-measurements have prediction errors,and their confidence intervals do not necessarily contain the truth values,leading to estimation biases of the *** solve this problem,this paper proposes a pseudo-measurement interval prediction framework based on the Gaussian process regression(GPR)model,thereby improving the prediction accuracy of pseudo-measurement confidence ***,a weight assignment strategy for improving the robustness of weighted least squares(WLS)ISE is *** strategy quantifies the deviation between the pseudo-measurement intervals and their estimated intervals and assigns smaller weights to the pseudo-measurement intervals with larger deviations,thereby improving the estimation accuracy and robustness of the *** paper adopts the data from the supervisory control and data acquisition(SCADA)system of the New York Independent System Operator(NYISO).It verifies the advantages of the GPR method for pseudo-measurement interval prediction by comparing it with the quantile regression and neural network *** addition,this paper demonstrates the effectiveness of the proposed weight assignment strategy through the IEEE 14-bus ***,the differences in the estimation accuracy and the bad data identification between the robust interval state estimation and deterministic state estimation are discussed.

关键词： Interval state estimation interval analysis pseudo-measurement Gaussian process regression(GPR)

Enhancing lithium-sulfur battery performance with In_(2)O_(3)-In_(2)S_(3)@NSC heterostructures:Synergistic effects of double barrier and catalytic transformation

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Journal of Materials Science & Technology 2024年第2期169卷 105-114页

作者： Deqing He Chunyu Zhu Yutao huo Zhonghao Rao School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Thermal Science and Energy Clean Utilization Hebei University of TechnologyTianjin 300401China School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou 221116China

The sluggish redox reaction kinetics of lithium polysulfides(LiPSs)are considered the main obstacle to the commercial application of lithium-sulfur(Li-S)*** accelerate the conversion by catalysis and inhibit the shuttling of soluble LiPSs in Li-S batteries,a solution is proposed in this *** solution involves fabrication of N,S co-doped carbon coated In_(2)O_(3)/In_(2)S_(3)heterostructure(In_(2)O_(3)-In_(2)S_(3)@NSC)as a multifunctional host material for the *** In_(2)O_(3)-In_(2)S_(3)@NSC composite can reduce the Gibbs free energy for the conversion reactions of LiPSs,which results in superior *** synergy between different components in In_(2)O_(3)-In_(2)S_(3)@NSC and the unique 3D structure facilitate ion and electron transport in Li-S *** In_(2)O_(3)-In_(2)S_(3)@NSC/Li 2 S 6 cathode exhibits excellent rate capacity,with a capacity of 599 mAh g−1 at 5.5 C,and good cycle stability,with a capacity of 436 mAh g^(−1)after 1000 cycles at 1 ***,this study proposes a promising solution to improve the energy storage properties of Li-S batteries,which could potentially facilitate the commercialization of Li-S batteries.

关键词： Li-S battery Multifunctional host material Synergy Heterostructures Energy storage properties

Asymmetric dark matter and Sommerfeld enhancement

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Communications in Theoretical Physics 2024年第8期76卷 120-125页

作者： Sujuan Qiu Hoernisa Iminniyaz Wensheng huo School of Physics Science and Technology Xinjiang University

We study the relic density of asymmetric dark matter with long-range interactions by considering the Sommerfeld effect. We find that the annihilation cross section of asymmetric dark matter is enhanced by the Sommerfeld effect and thus the relic density is decreased. Then we use the Planck data to constrain the asymmetry factor, coupling, and to derive the upper bounds on the dark matter mass in s-wave and p-wave annihilation cases.

关键词： asymmetric dark matter relic density Sommerfeld enhancement

Rotor Angle Stability Prediction Using Temporal and Topological Embedding Deep Neural Network Based on Grid-informed Adjacency Matrix

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 695-706页

作者： Peiyuan Sun Long huo Xin Chen Siyuan Liang the School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China the School of Electrical Engineering and the Center of Nanomaterials for Renewable EnergyState Key Laboratory of Electrical Insulation and Power EquipmentXi’an Jiaotong UniversityXi’an 710049China the Department of Computer Science and Engineering The Chinese University of Hong KongShatin999077Hong KongChina

Rotor angle stability(RAS)prediction is critically essential for maintaining normal operation of the interconnected synchronous machines in power *** wide deployment of phasor measurement units(PMUs)promotes the development of data-driven methods for RAS *** paper proposes a temporal and topological embedding deep neural network(TTEDNN)model to accurately and efficiently predict RAS by extracting the temporal and topological features from the PMU *** grid-informed adjacency matrix incorporates the structural and electrical parameter information of the power *** the small-signal RAS with disturbance under initial operating conditions and the transient RAS with short circuits on transmission lines are *** studies of the IEEE 39-bus and IEEE 300-bus power systems are used to test the performance,scalability,and robustness against measurement uncertainties of the TTEDNN *** show that the TTEDNN model performs best among existing deep learning ***,the superior transfer learning ability from small-signal RAS conditions to transient RAS conditions has been proved.

关键词： Rotor angle stability prediction topological embedding deep learning graph convolution network

Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–H bond: quick access to multi-substituted aryl olefins

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Science China Chemistry 2024年第3期67卷 882-889页

作者： Jian Yao Lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct C–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–H functionalization

Intensifying electrified flow-through water treatment technologies via local environment modification

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 17-25页

作者： Zheng-Yang huo Xiaoxiong Wang Xia Huang Menachem Elimelech School of Environment and Natural Resources Institute of Ecological CivilizationRenmin University of ChinaBeijing 100872China Institute for Ocean Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Center of Double Helix Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Department of Chemical and Environmental Engineering Yale UniversityNew HavenCT 06520-8286USA

Removing high-risk and persistent contaminants from water is challenging,because they typically exist at low concentrations in complex water *** flow-through technologies are viable to overcome the limitations induced by mass transport for efficient contaminant *** the local environment of the flow-through electrodes offers opportunities to further improve the reaction kinetics and selectivity for achieving near-complete removal of these contaminants from ***,we present state-of-the-art local environment modification approaches that can be incorporated into electrified flow-through technologies to intensify water *** first show methods of nanospace incorporation,local geometry adjustment,and microporous structure optimization that can induce spatial confinement,enhanced local electric field,and microperiodic vortex,respectively,for local environment *** then discuss why local environment modification can complement the flow-through electrodes for improving the reaction rate and ***,we outline appropriate scenarios of intensifying electrified flow-through technologies through local environment modification for fit-for-purpose water treatment applications.

关键词： Point-of-use water treatment Electrified membrane Advection-enhanced mass transport Water decontamination and disinfection Emerging contaminants