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Journal of Materials Science & Technology 2023年第15期146卷 252-258页

作者： Huabei Peng xiao Yang Lixin Sun Liqiu yong Jiazhen Yan Jinyong Zhang Bingnan qian Yuhua Wen School of Mechanical Engineering Sichuan UniversityChengdu 610065China School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials and Physics China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Innovation Center NPU ChongqingChongqing 401135China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055China

Omega(ω)phase has a trigonal or hexagonal crystal structure and was first discovered inβ-type Ti-Cr alloys[1].Since then,theω-phase has been widely reported in numerous group IV transition metal(Ti,Ta,Hf,and Zr)based alloys[2–9].The morphologies ofω-phase could be particle-like(athermalω-phase)[10],ellipsoidal or cuboidal after aging(isothermalω-phase)[11],and plate-like after deformation(stress-relatedω-phase)[12].Amongst,the stressrelatedω-phase is usually located at the twinning boundary,thus also called interfacial-twin-boundary-ω(ITB-ω)*** formation of the ITB-ωphase is considered to be related to the formation of{112}bccmechanical twin(i.e.,{112}bcc twin)in bodycentered cubic(BCC)metals and alloys[13].

关键词： alloys alloy deformation

Rhodium-catalyzed Doyle-Kirmse rearrangement reactions of sulfoxoniun ylides

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Chinese Chemical Letters 2024年第4期35卷 363-366页

作者： Ying-Di Hao Zhi-qian Lin xiao-Yu Guo Jiao Liang Can-Kun Luo qian-Tao Wang Li Guo yong Wu Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Department of Medicinal Chemistry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Doyle-Kirmse rearrangement reactions have received continuous attention as an important method for constructing complex chemical structures. Herein, we disclosed an efficient rhodium-catalyzed DoyleKirmse rearrangement reaction, which can simultaneously construct C–C bonds and C–X(X = S/Se) bonds using sulfoxonium ylides as starting materials to obtain sulfur-or selenium-containing compounds. This strategy is characterized by the safer and greener carbene precursor, high yields and broad substrate scope, possessing a wide range of application.

关键词： Sulfoxonium ylides Rhodium(Ⅱ)-catalyzed Carbene Rearrangement reactions One-pot process

A phenylphenthiazide anchored Tb（Ⅲ）-cyclen complex for fluorescent turn-on sensing of ClO-

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Chinese Chemical Letters 2025年第2期 297-301页

作者： Ya-Ping Liu Zhi-Rong Gui Zhen-Wen Zhang Sai-Kang Wang Wei Lang Yanzhu Liu qian-yong Cao School of Chemistry and Chemical Engineering Nanchang University

A phenylphenothiazine anchored Tb（Ⅲ）-cyclen complex PTP-Cy-Tb for hypochlorite ion（ClO-） detection has been designed and prepared. PTP-Cy-Tb shows a weak Tb-based emission with AIE-characteristics in aqueous solutions. After addition of ClO-, the fluorescence of PTP-Cy-Tb gives a large enhancement for oxidization the thioether to sulfoxide group. The detection limit of PTP-Cy-Tb toward ClO-is as low as 8.85 nmol/L. The sensing mechanism was detailedly investigated by time of flight mass spectrometer（TOF-MS）, Fourier transform infrared spectroscopy（FT-IR） and density functional theory（DFT） *** addition, PTP-Cy-Tb has been successfully used for on-site and real-time detection of ClO-in real water samples by using the smartphone-based visualization method and test strips.

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Novel Bilayer-Shelled N,O-Doped Hollow Porous Carbon Microspheres as High Performance Anode for Potassium-Ion Hybrid Capacitors

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Nano-Micro Letters 2023年第9期15卷 423-435页

作者： Zhen Pan yong qian Yang Li xiaoning Xie Ning Lin Yitai qian Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026People’s Republic of China yongjiang Laboratory Ningbo 315202People’s Republic of China China National Building Material Design&Research Institute Co. Ltd.No.208Huazhong RoadGongshu DistrictHangzhou 310022People’s Republic of China

With the advantages of high energy/power density,long cycling life and low cost,dual-carbon potassium ion hybrid capacitors(PIHCs)have great potential in the field of energy ***,a novel bilayer-shelled N,O-doped hollow porous carbon microspheres(NOHPC)anode has been prepared by a self-template method,which is consisted of a dense thin shell and a hollow porous spherical ***,the NOHPC anode possesses a high K-storage capacity of 325.9 mA h g^(−1)at 0.1 A g^(−1)and a capacity of 201.1 mAh g^(−1)at 5 A g^(−1)after 6000 *** combination with ex situ characterizations and density functional theory calculations,the high reversible capacity has been demonstrated to be attributed to the co-doping of N/O heteroatoms and porous structure improved K+adsorption and intercalation capabilities,and the stable long-cycling performance originating from the bilayer-shelled hollow porous carbon sphere ***,the hollow porous activated carbon microspheres(HPAC)cathode with a high specific surface area(1472.65 m^(2)g^(−1))deriving from etching NOHPC with KOH,contributing to a high electrochemical adsorption capacity of 71.2 mAh g^(−1)at 1 A g^(−1).Notably,the NOHPC//HPAC PIHC delivers a high energy density of 90.1 Wh kg^(−1)at a power density of 939.6 W kg^(−1)after 6000 consecutive charge-discharge cycles.

关键词： Self-template method Bilayer-shelled hollow porous structure N,O-doped carbon microspheres Dual-carbon potassium‐ion hybrid capacitor

Towards low emissions and high thermal efficiency of gasoline compression ignition engine under high loads by modulating the fuel reactivity and injection strategy

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Science China(Technological Sciences) 2020年第1期63卷 96-104页

作者： JIANG ChenXu LI ZiLong qian yong LU XingCai Key Lab for Power Machinery and Engineering of MOE Shanghai Jiao Tong University

Gasoline compression ignition(GCI) is a practicable way to obtain low emissions and high thermal efficiency of gasoline-like fuels in internal combustion engines. In this paper, the research octane number(RON) and injection strategy were coordinated to optimize the GCI engine performance and emissions under high loads. The direct injection and port injection were used to achieve two injection strategies: direct injection(DI) and port injection plus direct injection(PIDI), and the primary reference fuels(PRF) with the RON of 60, 70, 80 and 90 were used. The results show that using lower RON fuels under high loads, DI mode can achieve higher efficiency, while PIDI mode can achieve lower combustion noise at an expense of slightly lower fuel economy. When the DI mode is converted to PIDI mode with a pre-injection ratio of 30%, using PRF70 under 12 bar and the exhaust gas recirculation(EGR) rate of 40%, the gross indicated thermal efficiency and the maximum pressure rise rate are reduced by 1% and by 2 bar/°CA, respectively, while the particle emissions also decrease significantly, thus achieving low emissions and high efficiency. However, under the same load and EGR rate, DI mode produces less regulated and unregulated emissions than PIDI mode. In addition, the effect of fuel RON was obvious, the lower RON fuels exhibit obvious three-stage heat release in PIDI mode, however, PRF90 with higher RON only exhibits two-stage heat release, and the peak value of the firststage heat release rate is also lower than those of other fuels.

关键词： gasoline compression ignition regulated and unregulated emissions injection strategy particle emissions fuel reactivity

Effects ofmodulenumberand firing conditiononchargethermal safetyingunchamber

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Defence Technology（防务技术） 2022年第1期18卷 27-37页

作者： Huan-yu qian yong-gang Yu Jing Liu School of Energy and Power Engineering Nanjing University of Science and Technology Narjing 21094 China Acudemny of Opto-Electroric China Electronis Technology Group Corporation(AOE CETC)Tianjin300308China

Thermal safety of modular charge which is fed into and retained in the chamber after gun fires consecutively is first investigated with cook-off method,A two-dimensional cook-off model of modular charge in gun chamber is established and the cook-off process of modular charge in gun chamber is numerically *** the effects of module number and firing condition on charge thermal safety are evaluated by researching the cook-off response characteristics of *** results show that under conditions of different module numbers the cook-off responses all occur on the module closest to the boundary of missile,and the single-base propellants located at the inner surface of cartridge ignite *** the number of loaded module changes from 1 to 6,the cook-off response temperatures vary little,only in a small range of 478.1 K-482.4 *** cook-off response times decrease logarithmically in the range of 211.25-166.7 s with the increasing length of residual air gap in gun *** simulation results are well matched with the experimental ***,different firing conditions have greatinfluence on the cook-off response time,minor influence on the initial response position and little in-fluence on the response *** the three conditions of consecutive 32 launches with 5 rounds/min,43 launches with 1 round/min,and 41 launches with different firing frequencies,the cook off response temperatures are 479.2 K,481.1 K and 479.9 K respectively and the response times are 709.25,211.2 s and 214.4 s *** response position is near the middle area of the inner cartridge surface in the former condition and near the right area in the latter two conditions.

关键词： Thermal safety Modular charge Cook-off Firing condition

Ginsenoside Rk1 suppresses pro-inflammatory responses in lipopolysaccharide-stimulated RAW264.7 cells by inhibiting the Jak2/Stat3 pathway

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Chinese Journal of Natural Medicines 2017年第10期15卷 751-757页

作者： YU qian ZENG Ke-Wu MA xiao-Li JIANG yong TU Peng-Fei WANG Xue-Mei Research Studio of Integration of Traditional and Western Medicine First HospitalPeking UniversityBeijing 100034China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

The saponin ginsenoside Rk1 is a major compound isolated from *** Rk1 has been reported to have anti-inflammatory and anti-tumor properties and to be involved in the regulation of ***,the effect and mechanism of anti-inflammatory action of ginsenoside Rk1 has not been fully *** investigated whether ginsenoside Rk1 could suppress the inflammatory response in lipopolysaccharide-stimulated RAW264.7 macrophages and to explore its mechanism of the ***264.7 cells were treated with LPS(1 μg×mL^(–1))in the absence or the presence of Ginsenoside Rk1(10,20,and 40 μmol×L^(–1)).Then the inflammatory factors were tested with Griess reagents,ELISA,and *** proteins were analyzed by Western *** Rk1 inhibited lipopolysaccharide-induced expression of nitric oxide(NO),interleukin(IL)-6,IL-1β,tumor necrosis factor(TNF)-α,and monocyte chemotactic protein(MCP)-*** Rk1 inhibited the lipopolysaccharide-stimulated phosphorylation of NF-κB and janus kinase(Jak)2 and signal transducer and activator of transcription(Stat)3 at Ser727 and *** data suggested that ginsenoside Rk1 could inhibit expression of inflammatory mediators and suppress inflammation further by blocking activation of NF-κB and the Jak2/Stat3 pathway in LPS-stimulated RAW264.7 cells.

关键词： Inflammation RAW264.7 cells Ginsenoside Rkl Jak2/Stat3 NF-xB

Vegetation changes in the agricultural-pastoral areas of northern China from 2001 to 2013

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Journal of Integrative Agriculture 2016年第5期15卷 1145-1156页

作者： SU Wei YU De-yong SUN Zhong-ping ZHAN Jun-ge LIU xiao-xuan LUO qian State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 P.R. China State Key Laboratory of Remote Sensing Science/School of Geography Beijing Normal University Beijing 100875 P.R.China Satelfite Environment Center Ministry of Environmental Protection Beijing 100094 PR.China College of Information and Electrical Engineering China Agricultural University Beijing 100083 P.R.China

Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. However, such studies have placed little emphasis on vegetation change and spatial variation in this type of ecotone. Accordingly, this study analyzed the changes in vegetation type and growth using the 16-d composite MOD13A1 product with 1-km resolution and MOD12Q1 product with 1-km resolution. We used the mean, maximum, standard deviation normalized-difference vegetation index（NDVI） values, and the rate of change（ROC） of NDVI value to explain vegetation changes within the studied ecotone. Our results showed that significant vegetation type and growth changes have occurred in the study area. From 2001 to 2013, for example, with the exception of 2001, 2004 and 2009, a certain extent of grassland area was converted to cropland. Drought severity index（DSI） results indicate that there exists drought in 2001, 2004 and 2009. Such temporal changes in cropland and grassland area confirmed the ecological vulnerability of the ecotone. At the same time, vegetation varied spatially from west to east and from south to north. The mean, maximum and standard deviation NDVI values were all sorted in descending order based on differences in latitude and longitude, as follows： NDVI_（2013）〉NDVI_（2009）〉NDVI_（2004）〉NDVI_（2001）

关键词： vegetation growth agricultural-pastoral area MODIS land cover change temporal change spatial variation

Simultaneous Identification of Process Structure, Parameters and Time-delay Based on Non-negative Garrote

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International Journal of Automation and computing 2020年第6期17卷 873-882页

作者： Jian-Guo Wang qian-Ping xiao Tiao Shen Shi-Wei Ma Wen-Tao Rao yong-Jie Zhang School of Mechatronical Engineering and Automation Shanghai UniversityShanghai Key Lab of Power Station Automation TechnologyShanghai 200072China Institute of Environment and Resources Baosteel Research InstituteShanghai 201900China

In practice,the model structure,parameters and time-delay of the actual process may vary ***,the general identification methods of the 3 items are performed with separate procedures which is very inconvenient in practical *** view of the fact that variable selection procedure can ensure a compact model with robust input-output,relation and in order to explore the feasibility of variable selection algorithm for the simultaneous identification of process structure,parameters and time-delay,non-negative garrote(NNG)algorithm is introduced and applied to system identification and the corresponding procedures are *** application of NNG variable selection algorithm to the identification of single input single output(SISO)system,multiple input multiple output(MIN1O)system and Wood-Berry tower industry are *** identification accuracy and the time-series variable selection results are analyzed and compared between NNG and ordinary least square(OLS)*** derived excellent results show that the proposed NNG-based modeling algorithm can be utilized for simultaneous identification of the model structure,parameters and time-delay with high precision.

关键词： Model structure model parameter time-delay non-negative garrote variable selection.

CoFe_2O_4-Graphene Nanocomposites Synthesized through An Ultrasonic Method with Enhanced Performances as Anode Materials for Li-ion Batteries

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Nano-Micro Letters 2014年第4期6卷 307-315页

作者： Yinglin xiao xiaomin Li Jiantao Zai Kaixue Wang yong Gong Bo Li qianyan Han Xuefeng qian School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

Co Fe2O4-graphene nanosheets(Co Fe2O4-GNSs) were synthesized through an ultrasonic method, and their electrochemical performances as Li-ion battery electrode were improved by annealing processes. The nanocomposites obtained at 350 °C maintained a high specific capacity of 1,257 m Ah g-1even after 200 cycles at 0.1 A g-1. Furthermore,the obtained materials also have better rate capability, and it can be maintained to 696, 495, 308, and 254 m Ah g-1at 1, 2,5, and 10 A g-1, respectively. The enhancements realized in the reversible capacity and cyclic stability can be attributed to the good improvement in the electrical conductivity achieved by annealing at appropriate temperature, and the electrochemical nature of Co Fe2O4 and GNSs during discharge–charge processes.

关键词： Cobalt ferrite Graphene Anode materials Lithium ion battery