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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu zhenhua wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

H_-/H_∞ fault detection filter design for interval time-varying delays switched systems

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Journal of Systems Engineering and Electronics 2016年第4期27卷 878-886页

作者： Jiawei wang Yi Shen zhenhua wang Department of Control Science and Engineering Harbin Institute of Technology

The problem of the robust fault detection filter design for time-varying delays switched systems is considered in the framework of mixed H-/H∞. Firstly, the weighted H∞ performance index is utilized as the robustness performance, and the H- index is used as the sensitivity performance for obtaining the robust fault detection filter. Then a novel multiple Lyapunov-Krasovskii function is proposed for deriving sufficient existence conditions of the robust fault detection filter based on the average dwell time technique. By introducing slack matrix variable, the coupling between the Lyapunov matrix and system matrix is removed, and the conservatism of results is reduced. Based on the robust fault detection filter, residual is generated and evaluated for detecting faults. In addition, the results of this paper are dependent on time delays,and represented in the form of linear matrix inequalities. Finally,the simulation example verifies the effectiveness of the proposed method.

关键词： switched system average dwell time mixed H-/H∞ robust fault detection filter time-varying delay

Effects of(Ti, W)C Addition on the Microstructure and Mechanical Properties of Ultrafine WC–Co Tool Materials Prepared by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2020年第6期33卷 892-902页

作者： Boxiang wang zhenhua wang Juntang Yuan Bin Yu School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

In this study, powder mixtures containing(Ti, W)C additions(10, 20, 30 and 40 wt%) were prepared and then consolidated at 1200, 1250, 1300 and 1350 °C by spark plasma sintering. The effect of(Ti, W)C additions on the microstructure and mechanical properties of ultrafine WC–Co materials was investigated. The results demonstrate that the(Ti, W)C not only retards the sintering densification but also increases the porosity of sintered samples. The increasing sintering temperature is beneficial to the densification but results in the grain coarsening and the dissolution of W in(Ti, W)C. Moreover, there are no(Ti, W)C grains with obvious core/rim structure in the microstructure. With the(Ti, W)C increasing from 10 to 20 wt%, the hardness increases and fracture toughness changes hardly. However, the hardness and fracture toughness decrease slightly as the(Ti, W)C further increases. The transgranular fracture of(Ti, W)C phases is responsible for the slight reduction in fracture toughness. The sample with 20 wt%(Ti, W)C has high hardness and fracture toughness( HV : 21.3 GPa, KIC: 9.8 MPa m1/2).

关键词： (Ti,W)C Cemented carbides Spark plasma sintering Microstructure Mechanical properties

Satellite fault diagnosis method based on predictive filter and empirical mode decomposition

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Journal of Systems Engineering and Electronics 2011年第1期22卷 83-87页

作者： Yi Shen Yingchun Zhang zhenhua wang School of Astronautics Harbin Institute of Technology Harbin 150001 E R. China

A novel satellite fault diagnosis scheme is presented based on the predictive filter and empirical mode composition（EMD）.First,the predictive filter is utilized to obtain the fault estimation,which is corrupted by *** the EMD method is introduced to decompose the fault estimation into a finite number of intrinsic mode functions and extract the trend of faults for fault *** proposed scheme has the ability of diagnosing both abrupt and incipient faults of the actuator in a satellite attitude control subsystem.A mathematical simulation is given to illustrate the effectiveness of the proposed scheme.

关键词： satellite fault diagnosis predictive filter empirical mode decomposition(EMD).

Comparison of Carboxylic Acids in Some Crude Oils and Their Diesel Distillates and VGOs:Characterized by Negative-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (Negative-Ion ESI FT-ICR MS)

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China Petroleum Processing & Petrochemical Technology 2011年第3期13卷 8-15页

作者： wang zhenhua Tu Yongshan Process Department China Tianchen Engineering Corporation Tianjin 300400 State Key Laboratory of Heavy Oil Processing China University of Petroleum Qingdao 266555

Three high-acidity crudes, Dar, SZ36-1, and QHD326, were separated through distillation into several fractions, including diesel distillates, and VGOs. Samples were characterized by negative-ion ESI FT-ICR MS. The O2 class species （petroleum carboxylic acids）, which have a close relationship with corrosion of equipment caused by high-acidity crudes, were put in the focus of attention and were discussed in this paper. Monocyclic, bicyclic, and tricyclic naphthenic acids are the main types of petroleum carboxylic acids in naphthenic-base crudes （SZ36-1 and QHD326）. But the main types of petroleum carboxylic acids in paraffinic-base crude （Dar） are aliphatic acids and monocyclic naphthenic acids. The O2 class species in SZ36-1 and QHD326 are distributed in a wider range and have bigger DBE value （double-bond equivalence value） and carbon number than Dar. Bicyclic naphthenic acids have the highest proportion among petroleum carboxylie acids in diesel distillates, but monocyclic and tricyclic naphthenic acids also occupy a high proportion. Particularly, aliphatic acids in the diesel distillate of Dar still have high proportion among petroleum carboxylic acids. The distribution of petroleum carboxylic acids in VGO is basically identical. The bicyclic naphthenic acids assume the first place （about 25 m%）, while the monocyclic and tricyclic naphthenic acids take the next place. The comparison of petroleum carboxylic acids in diesel distillates and VGOs has revealed that the molecules of carboxylic acids in VGOs are not only bigger but also more complicated.

关键词： O2 class species petroleum carboxylic acids aliphatic acids naphthenic acid

Balancing particle properties for practical lithium-ion batteries

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Particuology 2022年第2期20卷 18-29页

作者： Jing Zhang Jinshuo Qiao Kening Sun zhenhua wang Beijing Key Laboratory for Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

As a state-of-the-art secondary battery,lithium-ion batteries(LIBs)have dominated the consumer electronics market since Sony unveiled the commercial secondary battery with LiCoO_(2) as the negative electrode material in the early *** key to the efficient operation of LIBs lies in the effective contact between the Li-ion-rich electrolyte and the active material particles in the *** particle properties of the electrode materials affect the lithium ion diffusion path,diffusion resistance,contact area with the active material,the electrochemical performance and the energy density of *** achieve satisfied comprehensive performance and of LIBs,it is not only necessary to focus on the modification of materials,but also to balance the properties of electrode material ***,in this review,we analyze the influence of particle properties on the battery performance from three perspectives:particle size,particle size distribution,and particle shape.A deep understanding of the effect and mechanism of particles on electrodes and batteries will help develop and manufacture practical LIBs.

关键词： Lithium-ion battery Particle properties Particle size Particle size distribution Particle shape

Distribution of Carboxylic Acids in Sudanese Dar Crude Oil: Characterized by Negative-Ion Electrospray Ionization Fou- rier Transform Ion Cyclotron Resonance Mass Spectrometry

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China Petroleum Processing & Petrochemical Technology 2011年第4期13卷 15-22页

作者： wang zhenhua Tu Yongshan China Tianchen Engineering Corporation Tianjin 300400 State Key Laboratory of Heavy Oil Processing China University of Petroleum Qingdao 266555

The Dar crude oil produced in Sudan was distilled into several fractions. The heteroatom class species in crude and its fractions were characterized by the negative-ion ESI FT-ICR MS. The major emphasis was put upon the study on the O2 class species (petroleum carboxylic acids). The test results revealed that aliphatic acids and monocyclic naphthenic acids accounted for a large proportion in petroleum carboxylic acids of the Dar crude. The relative abundance of aliphatic acids and monocyclic naphthenic acids decreased with an increasing boiling point of fractions. Meanwhile, the relative abundance of bicyclic and tricyclic naphthenic acids increased at first and then decreased, whereas the relative abundance of petroleum carboxylic acids with higher double-bond equivalence (DBE) values increased. The high abundance of aliphatic acids in the Dar crude and its fractions covered the carbon numbers in a range of 16 to 18 which had important geochemical signifi- cance. The O2 class species were distributed in a broad range of DBE values and carbon numbers with increasing boiling points of fractions.

关键词： O2 class species petroleum carboxylic acids DBE aliphatic acids naphthenic acids.

CONSENSUS DESIGN FOR CONTINUOUS-TIME MULTI-AGENT SYSTEMS WITH COMMUNICATION DELAY

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Journal of Systems Science & Complexity 2014年第4期27卷 701-711页

作者： wang zhenhua YOU Keyou XU Juanjuan ZHANG Huanshui School of Control Science and Engineering Shandong University Department of Automation Tsinghua University

This paper investigates a consensus design problem for continuous-time first-order multiagent systems with uniform constant communication *** that the agent dynamic is unstable and the diagraph is undirected,sufficient conditions are derived to guarantee *** key technique is the adoption of historical input information in the ***,when agent's own historical input information is used in the protocol design,the consensus condition is constructed in terms of agent dynamic,communication delay,and the eigenratio of the network *** result is presented to validate the effectiveness of the theoretical result.

关键词： Communication delay consensus protocol eigenratio historical input information multi-agent systems.

Non-Point-Source Nitrogen and Phosphorus Loadings from a Small Watershed in the Three Gorges Reservoir Area

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Journal of Mountain Science 2012年第1期9卷 10-15页

作者： ZHU BO wang zhenhua wang Tao DONG Zhixin Key Laboratory of Mountain Environment Evolvement and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Non-point-source pollution has become a major threat to the water quality of the Three Gorges Reservoir(TGR);however,nutrient loadings from terrestrial sources are unclear due to a lack of in situ monitoring.A representative small watershed in the central part of the TGR area was selected to monitor the loss of nitrogen(N) and phosphorous(P) continuously along with the runoff from 2007 through 2009 to understand the exact sources and *** show that the non-point-source nitrogen and phosphorus comes mainly from the storm runoff from residential areas,citrus orchards and sloping croplands,which contributes up to 76% of the loadings in this ***,a crucial measure for controlling non-point-source pollution is to intercept storm runoff from the three *** fields provide a sink for non-point-source N and P by intercepting the runoff and sediment along with their different forms of nitrogen and *** N and P removal efficiency by paddy fields from residential areas is within the range of 56% to 98%.Paddy fields are an important land-use option for reducing the non-point-source loading of N and P in the TGR area.

关键词： Non-point-source pollution Source and sink Nitrogen Phosphorus Paddy fields Three Gorges Reservoir area China

Phosphorus Sorption-desorption Characteristics of Ditch Sediments from Different Land Uses in a Small Headwater Catchment in the Central Sichuan Basin of China

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Journal of Mountain Science 2012年第3期9卷 441-450页

作者： wang zhenhua HE Min wang Tao ZHU BO Key Laboratory of Mountain Environment Evolvement and Regulation Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Department of Water Environment Research Changjiang River Scientific Research InstituteWuhan 430010China Faculty of Forestry Sichuan Agriculture UniversityYa'an 625014China

Investigation of phosphorus (P) sorption-desorption characteristics of drainage ditch sediments is important for better understanding on sediment P transport behaviors in ditches. Surface ditch sediment samples were collected from headwater sub-catchment of forestland, sloping cropland, paddy field, and residential area in a representative catchment in the central Sichuan Basin. These sediment samples were used for determination of P sorption-desorption characteristics by a batch equilibrium technique. Results showed that the maximum P sorption capacities (Qm) in the sediments ranged from 159.7 to 263.7 mg/kg, while higher Qm were observed in the ditch sediments from the paddy fields. The Qm was significantly and positively correlated with oxalate-extractable Fe and Al oxides (r=0.97 and 0.98, p 50 g/kg) would not increase P sorption capacity in the ditch sediments. The ditch sediments featured a linear desorption curve, suggesting that P release risk would be enhanced with the increase of the P adsorption. The P desorption rate was positively correlated with Olsen P (r = 0.94, p < 0.01), but negatively related to the fine particle-size fractions (r = -0.92, p < 0.01), the sum of the amorphous Fe and Al oxides (r = -0.67, p < 0.05) and the P sorption capacity (r = -0.59, p < 0.05). The ditch sediments from residential area had a higher P release risk than that from the other ditches of forestland, sloping cropland and paddy field. The P sorption index (PSI) derived from single-point measurement was significantly correlated with the P sorption capacity (r = 0.99, p < 0.01), and could be used for estimating Qm as 1.64 times PSI plus 24.0 (Qm = 1.64 PSI + 24.0) for similar sediments

关键词： Ditch sediment Phosphorus sorption-desorption Sediment properties Land use