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Nanoscale transition metal catalysts anchored on perovskite oxide enabling enhanced kinetics of lithium polysulfide redox in lithium-sulfur batteries

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Journal of Energy Chemistry 2023年第6期81卷 432-442,I0010页

作者： Wenshuo Hou Ruilong Li zhenhua Wang Li Fang zhe bai Tan Wang Yu bai Kening Sun Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

To obtain high-performance lithium-sulfur(Li-S)batteries,it is necessary to rationally design electrocatalytic materials that can promote efficient sulfur electrochemical ***,the robust heterostructured material of nanoscale transition metal anchored on perovskite oxide was designed for efficient catalytic kinetics of the oxidation and reduction reactions of lithium polysulphide(Li PSs),and verified by density functional theory(DFT)calculations and experimental *** to the strong interaction of nanoscale transition metals with Li PSs through chemical coupling,heterostructured materials(STO@M)(M=Fe,Ni,Cu)exhibit excellent catalytic activity for redox reactions of Li *** bifunctional heterostructure material STO@Fe exhibits good rate performance and cycling stability as the cathode host,realizing a high-performance Li-S battery that can maintain stable cycling under rapid charge-discharge *** study presents a novel approach to designing electrocatalytic materials for redox reactions of Li PSs,which promotes the development of fast charge-discharge Li-S batteries.

关键词： Nanoscale transition metal Lithium polysulfide Catalytic activity Redox reaction Lithium-sulfur battery

Microstructure and mechanical properties of F_(GBA)/B_G air cooling bainitic steels containing niobium

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 429-434页

作者： Chun Feng Hong-sheng Fang Bing-zhe bai Yan-kang zheng Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The effect of different Nb additions on the mechanical properties and microstrucmre evolution of grain boundary allotriomorphic ferrite （FGBA） / granular bainite （BG） air cooling bainitic steels was investigated. The results indicate that the tensile strength and yield strength increase by 157 and 97 MPa, respectively with the addition of 0.02wt% Nb. The steel acquires superior strength and toughness with the addition of 0.06wt% Nb. The results of scanning electron microscopy and transmission electron microscopy reveal that the addition of Nb not only refines the size of granular bainite but also increases the volume fraction of granular bainite in FGBA/BG steels. The refinement effect of granular bainite is improved with the increase of Nb content.

关键词： granular bainite microstructure evolution mechanical properties Nb

Enhancing electrochemical conversion of lithium polysulfide by 1T-rich MoSe_(2) nanosheets for high performance lithium-sulfur batteries

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Chinese Chemical Letters 2023年第11期34卷 360-366页

作者： Ruilong Li zhe bai Wensuo Hou Zeyu Wu Pingli Feng Yu bai Kening Sun zhenhua Wang Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

The sluggish conversion kinetics and shuttle effect of lithium polysulfides(LiPSs)severely hamper the commercialization of lithium-sulfur *** electrocatalysts have been used to address these issues,amongst which,transition metal dichalcogenides have shown excellent catalytic performance in the study of lithium-sulfur *** that dichalcogenides in different phases have different catalytic properties,and such catalytic materials in different phases have a prominent impact on the performance of lithium-sulfur ***,1T-phase rich MoSe_(2)(T-MoSe_(2))nanosheets are synthesized and used to catalyze the conversion of *** with the 2H-phase rich MoSe_(2)(H-MoSe_(2))nanosheets,the T-MoSe_(2) nanosheets significantly accelerate the liquid phase transformation of LiPSs and the nucleation process of ***-situ Raman and X-ray photoelectron spectroscopy(XPS)find that T-MoSe_(2) effectively captures LiPSs through the formation of Mo-S and Li-Se bonds,and simultaneously achieves fast catalytic conversion of *** lithium-sulfur batteries with T-MoSe_(2) functionalized separators display a fantastic rate performance of 770.1 mAh/g at 3 C and wonderful cycling stability,with a capacity decay rate as low as 0.065%during 400 cycles at 1 *** work offers a novel perspective for the rational design of selenide electrocatalysts in lithium-sulfur chemistry.

关键词： MoSe_(2) Functionalized separator Lithium-sulfur battery Phase Catalytic conversion

Spinel-type bimetal sulfides derived from Prussian blue analogues as efficient polysulfides mediators for lithium-sulfur batteries

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Chinese Chemical Letters 2021年第12期32卷 4063-4069页

作者： Ruijian Li zhe bai Wenshuo Hou Jinshuo Qiao Wang Sun Yu bai zhenhua Wang Kening Sun Beijing Key Laboratory for Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

More and more attentions have been attracted by lithium-sulfur batteries(Li-S), owing to the high energy density for the increasingly advanced energy storage system. While the poor cycling stability, due to the inherent polysulfide shuttle, seriously hampered their practical application. Recently, some polar hosts,like single metal oxides and sulfides, have been employed as hosts to interact with polysulfide intermediates. However, due to the inherent poor electrical conductivity of these polar hosts, a relatively low specific capacity is obtained. Herein, a spinel-type bimetal sulfide NiCo_(2)S_(4)through a Prussian blue analogue derived methodology is reported as the novel host of polysulfide, which enables highperformance sulfur cathode with high Coulombic efficiency and low capacity decay. Notably, the Li-S battery with NiCo_(2)S_(4)-S composites cathode still maintains a capacity of 667 m Ah/g at 0.5 Cafter 300 cycles, and 399 m Ah/g at 1 C after 300 cycles. Even after 300 cycles at the current density of 0.5C, the capacity decays by 0.138% per cycle at high sulfur loading about 3 mg/cm;. And the capacity decays by0.026% per cycle after 1000 cycles, when the rate is 1C. More importantly, the cathode of Ni Co_(2)S_(4)-S composite shows the outstanding discharge capacity, owing to its good conduction, high catalytic ability and the strong confinement of polysulfides.

关键词： Polysulfide shuttle NiCo_(2)S_(4)L Ithium-Sulfur batteries

Research and modeling on correlation among microstructure,yield strength and process of bainite/martensite steel

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Journal of Iron and Steel Research International 2020年第7期27卷 834-841页

作者： Jia-jia Qiu Min Zhang Gu-hui Gao Zhun-li Tan Bing-zhe bai School of Mechanical Electronic and Control EngineeringMaterials Science and Engineering Research CenterBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The contributions of different strengthening mechanisms to yield strength of bainite/martensite multiphase rail steel with different finish cooling temperatures in the controlled cooling process were quantitatively *** density and substructure size of the rail steel were measured by scanning electron microscopy,electron backscatter diffraction and X-ray *** results show that the dislocation density increases with the decrease in block width in rail *** on the correlation among dislocation density,block width and yield strength,a physical model was proposed to predict the yield strength of rail *** variation of block width and dislocation density in different positions of rail head microstructure was integrated with temperature field *** density and block width reveal significant correlations with the finish cooling temperature.

关键词： bainite/martensite rail steel Temperature field simulation Controlled cooling process Yield strength Dislocation density

Ultra-high cycle fatigue behavior of high strength steel with carbide-free bainite/martensite complex microstructure

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 285-292页

作者： Xue-xia Xu Yang Yu Wen-long Cui Bing-zhe bai Jia-lin Gu Laboratory of Advanced Materials Department of Materials Science and Engineering Tsirtghua University Beijing 100084 China

The ultra-high cycle fatigue behavior of a novel high strength steel with carbide-free bainite/martensite （CFB/M） complex microstructure was studied. The ultra-high cycle fatigue properties were measured by ultrasonic fatigue testing equipment at a frequency of 20 kHz. It is found that there is no horizontal part in the S-N curve and fatigue fracture occurs when the life of specimens exceeds 10^7 cycles. In addition, the origination of fatigue cracks tends to transfer from the surface to interior of specimens as the fatigue cycle exceeds 10^7, and the fatigue crack originations of many specimens are not induced by inclusions, but by some kind of ＂soft structure＂. It is shown that the studied high strength steel performs good ultra-high cycle fatigue properties. The ultra-high fatigue mechanism was discussed and it is suggested that specific CFB/M complex microstructure of the studied steel contributes to its superior properties.

关键词： high strength steel ultra-high cycle fatigue bainite martensite fatigue behavior

Investigating aldehyde and ketone compounds produced from indoor cooking emissions and assessing their health risk to human beings

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Journal of Environmental Sciences 2023年第5期127卷 389-398页

作者： Wei Zhang zhe bai Longbo Shi Jung Hyun Son Ling Li Lina Wang Jianmin Chen Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China

Aldehyde and ketone compounds are ubiquitous in the air and prone to adverse effects on human *** emission is one of the major indoor *** to evaluate health risks associated with inhalation exposure to aldehyde and ketone compounds,13 carbonyl compounds(CCs)released from heating 5 edible oils,3 seasonings,and 2 dishes were investigated in a kitchen *** the scenarios of heating five types of oil,aldehydes accounted for 61.1%-78.0%of the total emission,mainly acetaldehyde,acrolein and ***,heating oil with added seasonings released greater concentrations of aldehyde and ketone *** concentration enhancement of larger molecular aldehydes was significantly *** emission factors of aldehyde and ketone compounds for cooking the dish of chili friedmeatweremuch greater compared to that of tomato fried ***,food materials also had a great impact on the aldehyde and ketone *** and acetaldehyde were the most abundant CCs in the *** concentrations ranged from 235.18 to 498.71μg/m^(3),which was about 100 times greater compared to the guidelines provided by Office of Environmental Health Hazard Assessment(OEHHA).The acetaldehyde inhalation for adultswas 856.83-1515.55μg and 56.23-192.79μg from exposure to chili fried meat and tomato fried eggs,*** exceeds the reference value of 90μg/day provided by *** findings of this study provided scientific evidences for the roles of cooking emissions on indoor air quality and human health.

关键词： Aldehyde and ketone Indoor cooking Emission factor Health risk

Homogenous strength-toughness match for 20Mn2SiCrMoV bainitic large-size parts via processing of VC particles and quenching control

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Rare Metals 2023年第10期42卷 3485-3496页

作者： Yu Tian Zhun-Li Tan Jin-Zhou Zhang zheng-Yuan Yuan Min Zhang Bing-zhe bai Material Science&Engineering Research Center School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing100084China

The problem of insufficient hardenability in general large-size parts always occurs in product manufacturing because of their large size,*** is restricted mainly by its own alloy composition with micro-alloy and key quenching and partitioning(Q&P) *** relationship between the cooling rate and properties of small samples was analyzed as the basis of the initial cooling rate at different positions corresponding to large-size parts combined with controlled austenization temperature in this *** as-treated micro structure after a fast cooling rate is mainly composed of lath bainite,martensite,and retained austenite(RA),while bainite and RA after a slow cooling *** showed that cooling control via decreasing spray intensity,meeting higher strength at the surface,and good strength and toughness match can be obtained both at the surface and in the ***-treated large ring part has~1330 MPa tensile strength and~95 J impact energy at the surface,and meantime,~1191 MPa tensile strength and~70 J impact energy in the center,which narrows the property difference.

关键词： Large-size parts Property homogeneity Cooling control bainite VC

Case for non-specific pain on waist of a pregnant woman

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World Journal of Acupuncture-Moxibustion 2019年第4期29卷 322-324页

作者： Da-zhe Tian Ying-zhe bai Nai-qi Li Tongdatang Traditional Chinese Medical Clinic of Cangzhou Cangzhou 061000Hebei ProvinceChina Integrated TCM&Western Medicine Hospital Cangzhou 061000Hebei ProvinceChina School of TCM Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

The patient was in conception 27 weeks+6 days,and got right waist pain,complicated with nausea,vomiting(vomit as gastric content),which was diagnosed as non-specific pain on waist after consultations of many *** patient received acupuncture with the following acupoints:Shuǐgōu(水沟 GV26),Yìntáng(印堂 EX-HN3),left Hégǔ(合谷 LI4),and right Tàichōng(太冲 LR3).On the first date of acupuncture,the patient felt pain relieved obviously,occasionally with slight pain that did not influence normal diet and *** the next day,the patient took acupuncture continuously,the doctor added Tàixī(太溪 KI3)*** patient received acupuncture for 3 times in *** pain and soreness of the patient almost disappeared,only with slight discomfort occasionally that did not influence the normal *** follow-up half a year,the patient born a live male infant by cesarean section on March 20,2019,both the mother and her infant were safe.

关键词： Non-specific pain Waist Depression Acupuncture