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High Technology Letters 2015年第4期21卷 433-438页

作者：阎昱 wu qingyuan Ai Zhengqing Jia Fanghui School of Mechanical and Materials Engineering North China University of Technology

The application of advanced high strength steel （AHSS） has an important significance in the development of the lightweight of automobile, but the parts made of AHSS usually have defects, such as fracture and large amount of springback, etc. In this paper, a model of multi-pass roll form- ing and springback process of AHSS is established with finite element software ABAQUS. Then a roll forming experiment is performed, and simulation and experimental results have been compared and analyzed. The model is established under complex contact conditions, including self-contact condi- tion. The results shows that during the process of sheet bending, large Mises stresses appear at ben- ding corners. The smaller the bending radius is, the larger the Mises stress and strain are. Thick- ness of sheet metal changes exceeds a certain limit, the differently if the bending radius is different. When the bending radius change tendency of the sheet thickness turns from increase to decrease.

关键词： roll forming FEM simulation springback experiment complex contact condition

Supported Atomically Dispersed Pd Catalyzed Direct Alkoxylation and Allylic Alkylation

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Chinese Journal of Chemistry 2024年第7期42卷 719-724页

作者： Ruixuan Qin Ziwen Chen qingyuan wu Nanfeng Zheng Pengxin Liu New Cornerstone Science Laboratory State Key Laboratory for Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy Materialsand National&Local Joint Engineering Research Center of Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China Innovation Laboratry for Scences and Technoogies of Energy Materials of Fujan Province(IKKM) Xiamen Fujian 361102China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China Fujian Key Laboratory of Rare-earth Functional Materials Fujian Shanhai Collaborative Innovation Center of Rare-earth Functional MaterialsLongyanFujian 366300China

A new approach to allylic alkylation is realized using an atomically dispersed palladium catalyst(Pd1/TiO2-EG).Unlike conventional methods that require derivation of substrates and utilization of additives,this method allows for direct allylic alkylation from allylic alcohols,producing H2O as the sole *** catalyst's high efficiency is attributed to the local hydrogen bonding at the or-ganic-inorganic interface(Pd-EG interface),facilitating hydroxyl group activation forη3π-allyl complex *** system demonstrates successful direct C—O and C—C coupling reactions with high selectivity,requiring no *** study highlights the potential of supported atomically dispersed catalysts for greener and more efficient catalysis,meanwhile,offers unique insights into the distinct behavior of atomically dispersed catalysts in comparison to homogeneous or nanoparticle-based catalysts.

关键词： Atomically dispersed catalyst Alkylation C—C coupling Organic-inorganic Interface Hydrogen bond Tsuji-Trost reaction Green catalysis

Long-term trend of water vapor over the Tibetan Plateau in boreal summer under global warming

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Science China Earth Sciences 2022年第4期65卷 662-674页

作者： Jingwen YU Qingquan LI Yihui DING Jie ZHANG qingyuan wu Xinyong SHEN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory on Climate and Environment ChangeNanjing University of Information Science&TechnologyNanjing 210044China Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

In this study,the long-term trend of water vapor over the Tibetan Plateau(TP)in boreal summer is investigated by using observation and reanalysis data from 1979 to *** historical experiment simulations of 19 models that participated in the Coupled Model Intercomparison Project phase 6(CMIP6)are evaluated,and the future variation tendency under four emission scenarios is *** results indicate that the water vapor content and the net water vapor budget over the TP show notable increasing trends,which are mainly manifested by a significant increase in the net water vapor import and a significant decrease in the water vapor export on the eastern boundary of the *** is mainly due to an anomalous anticyclone from Lake Baikal to the Mongolian *** CMIP6 multi-model ensemble can well simulate the variation characteristics of the TP net water vapor *** projection results indicate that by the end of the twenty-first century,the water vapor content,the net water vapor import and precipitation over the TP will *** a high-emissions scenario and compared with the current period(1991–2014),these three variables will increase by 47.99%,59.77%and 18.59%in the long term(2081–2100),*** significant enhancement of meridional water vapor transport over the northern TP may be the main reason for the increase in humidity over the TP.

关键词： Tibetan Plateau Boreal summer Water vapor transport Long-term trend Projection

A bioactive nanocomposite sponge for simultaneous hemostasis and antimicrobial therapy

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Nano Research 2023年第3期16卷 4004-4012页

作者： Jiani Lei Shanshan Li Shuang Liu qingyuan wu Bolong Xu Zhijun Huang Nier wu Xiaolu Xiong Huiyu Liu Dongsheng Zhou Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBionanomaterials&Translational Engineering LaboratoryBeijing Key Laboratory of BioprocessBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China Beijing National Laboratory of Molecular Sciences Key Laboratory of Green PrintingInstitute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijing 100071China

Uncontrollable bleeding and bacterial infections are the major reasons for the high mortality of *** this study,a composite hemostatic chitosan sponge CaO_(2)@SiO_(2)/CS was prepared by combining a novel core-shell inorganic nano hemostatic CaO_(2)@SiO_(2)nanoparticles with carboxylated chitosan,which presents a multi-layered structure with a rough and hydrophilic surface for rapid absorption of *** the CaO_(2)@SiO_(2)nanoparticles in the CaO_(2)@SiO_(2)/CS come into contact with blood,the silanol group on its surface and the released H_(2)O_(2)and Ca2+can recruit and activate platelets,while generating fibrin clots and activating the endo-exogenous coagulation cascade reaction to achieve rapid *** H_(2)O_(2)released from CaO_(2)@SiO_(2)shows the antimicrobial capacity and stimulates the production of tissue factors by endothelial ***,the silica coating reduces the cytotoxicity of bare CaO_(2),thus reducing the risk of secondary bleeding at the site of vascular ***_(2)@SiO_(2)/CS(48 s)showed a 1.83-and 2.52-fold reduction in hemostasis time compared to commercial gelfoam and CS in a femoral artery hemorrhage *** study illustrates the hemostatic mechanism of CaO_(2)@SiO_(2)and provides a reference for the development of clinical biomedical inorganic hemostatic materials.

关键词： calcium peroxide coagulation mechanism composite sponge hemostasis antibacterial

Engineering Shewanella-re duce d graphene oxide aerogel biohybrid to efficiently synthesize Au nanoparticles

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Journal of Materials Science & Technology 2024年第1期168卷 50-61页

作者： Baocai Zhang Shulin Shao Huan Yu Qijing Liu Sicheng Shi qingyuan wu Zijie wu Yiyu Feng Yifei Wang Xi Sun Deguang wu Feng Li Hao Song Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China College of Biological Engineering Tianjin Agricultural UniversityTianjin 300384China Department of Brewing Engineering Moutai InstituteLuban AveRenhuai 564507China

Biosynthesizing Au nanoparticles(AuNPs)from gold-bearing scraps provides a sustainable method to meet the urgent demand for ***,it remains challenging to efficiently biosynthesize AuNPs of which the diameter is less than 10 nm from a trace amount of Au^(3+)concentration at the level of tens ***,we constructed an exoelectrogenic cell(eCell)-conductive reduced-graphene-oxide aero-gel(rGA)biohybrid by assembling Shewanella sp.S1(SS1)as living biocatalyst and rGA as conductive ad-sorbent,in which Au^(3+)at trace concentrations would be enriched by the adsorption of rGA and reduced to AuNPs through the extracellular electron transfer(EET)of *** regulate the size of the synthe-sized AuNPs to 10 nm,the strain SS1 was engineered to enhance its EET,resulting in strain RS2(pYYD-P tac-ribADEHC&pHG13-P_(bad)-omcC in SS1).Strain RS2 was further assembled with rGA to construct the RS2-rGA biohybrid,which could synthesize AuNPs with the size of 7.62±2.82 nm from 60 ppm Au^(3+)*** eCell-rGA biohybrid integrated Au^(3+)adsorption and reduction,which enabled AuNPs biosyn-thesis from a trace amount of Au^(3+).Thus,the required Au^(3+)ions concentration was reduced by one or two orders of magnitude compared with conventional methods of AuNPs *** work devel-oped an AuNPs size regulation technology via engineering eCell’s EET with synthetic biology methods,providing a feasible approach to synthesize AuNPs with controllable size from trace level of gold ions.

关键词： Au nanoparticles Exoelectrogenic cell(e-Cell) Shewanella Synthesis biology Extracellular electron transfer Reduced graphene oxide aerogel

Color center-richγ-Al_(2)O_(3)promotes propane dehydrogenation

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Science China Chemistry 2024年第12期67卷 4134-4141页

作者： Yu Wang Xiang Wang Mengfei Qiao qingyuan wu Kunlong Liu Xiaodong Yi Ruixuan Qin Gang Fu Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361102China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Material SciencesZhejiang Normal UniversityJinhua 321004China

The Pt Sn/Al_(2)O_(3)catalyst is commonly used in commercial propane dehydrogenation(PDH)processes,but it faces challenges in the deactivation and periodic regeneration due to metal aggregation and coke deposition at high *** Al_(penta)^(3+)has been proven to be beneficial for enhancing catalytic stability,bottom-up synthesis protocols usually restrict their ***,a facile post-treatment approach using acetic acid was applied to create color centers(electrons trapped within oxygen vacancies)onγ-Al_(2)O_(3).Notably,the content of Al_(penta)^(3+)was enriched to 18.3%.Then,the pre-established Pt Sn clusters were *** electrons facilitated the formation of ultrafine Pt Sn nanoparticles(~2 nm),and the Al_(penta)^(3+)sites prevented the sintering of Pt Sn by constructing the strong Al_(penta)^(3+)–O–Sn ***,the catalytic durability of the catalyst prepared by conventional impregnation methods was remarkably extended from 186 h for the color center-free sample to 1,000 h using the HAc–Al_(2)O_(3)*** facile post-modification was further successfully extended to commercial Al_(2)O_(3)pellets without altering their mechanical properties,highlighting its potential in industrial applications.

关键词： catalytic stability pentacoordinate Al^(3+) PtSn catalyst metal-support interaction mechanical strength

Copper-hydride nanoclusters with enhanced stability by N- heterocyclic carbenes

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Nano Research 2021年第9期14卷 3303-3308页

作者： Hui Shen Lingzheng Wang Omar Lopez-Estrada Chengyi Hu qingyuan wu Dongxu Cao Sami Malola Boon KTeo Hannu Hakkinen Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsNational&Local Joint Engineering Research Center of Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Departments of Physics and Chemistry Nanoscience CenterUniversity ofjyvdskyldFI-40014 JyvdskyldFinland

Copper-hydrides have been intensively studied for a long time due to their utilization in a variety of technologically important chemical ***,poor stability of the species severely hinders its isolation,storage and operation,which is worse for nano-sized *** report here an unprecedented strategy to access to ultrastable copper-hydride nanoclusters(NCs),namely,using bidentate N-heterocyclic carbenes as stabilizing ligands in addition to *** this work,a simple synthetic protocol was developed to synthesize the first large copper-hydride nanoclusters(NCs)stabilized by N-heterocyclic carbenes(NHCs).The NC,with the formula of Cu3i(RS)25(NHC)3H6(NHC=1,4-bis(1-benzyl-1 H-benzimidazol-1-ium-3-yl)butane,RS=4-fluorothiophenol),was fully characterized by high resolution Fourier transform ion cyclotron resonance mass spectrum,nuclear magnetic resonance,ultra-violet visible spectroscopy,density functional theory(DFT)calculations and single-crystal X-ray ***,the title cluster exhibits unprecedented Cu4 tetrahedron-based vertex-sharing(TBVS)superstructure(fusion of six Cu4 tetrahedra).Moreover,the ultrahigh thermal stability renders the cluster a model system to highlight the power of NHCs(even other carbenes)in controlling geometrical,electronic and surface structure of polyhydrido copper clusters.

关键词： metal clusters copper-hydride N-hetercxylic carbene stability superatom

Surface Coordination Decouples Hydrogenation Catalysis on Supported Metal Catalysts

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CCS Chemistry 2023年第5期5卷 1215-1224页

作者： qingyuan wu Wenting Zhou Hui Shen Ruixuan Qin Qiming Hong Xiaodong Yi Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsNational&Local Joint Engineering Research Center for Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005 Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361102

Supported metal catalysts integrating advantages of catalytic hydrogenation and stoichiometric reduction are highly desirable for the green production of fine *** catalytic hydrogenation into H_(2)activation and selective reduction taking place at different locations is expected to provide an effective strategy to fabricate such catalyst ***,we report a decoupled hydrogenation system by modifying Pt catalysts supported on reducible In2O3 with ethylenediamine(EDA).The system exhibits good catalytic performance in oximes production from nitroalkanes,an industrially important reaction,by employing H_(2).Systematic studies demonstrate that the surface coordination of EDA on Pt is crucial to passivate the Pt surface from nitro hydrogenation without inhibiting H_(2)*** activated H_(2)species can then transfer and reduce the In_(2)O_(3)support in situ to generate sustainable stoichiometric reducing agents for the chemoselective reduction of *** upon the mechanistic understanding,a sustainable strategy for the production of oximes has been successfully fabricated.

关键词： hydrogenation catalysis surface coordination reducible support selective hydrogenation of nitro compounds heterogeneous catalysis

External physical field-driven nanocatalytic cancer therapy

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BMEMat(BioMedical Engineering Materials) 2023年第1期1卷 52-69页

作者： qingyuan wu Haoyuan Zhang Huiyu Liu Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBeijing Laboratory of Biomedical MaterialsBionanomaterials&Translational Engineering LaboratoryBeijing Key Laboratory of BioprocessBeijing University of Chemical TechnologyBeijingChina

Recently,variable nanocatalysts have provided novel,highly selective,mini-mally invasive strategies driven by external physical fields for cancer *** the catalytic reaction,less toxic or nontoxic substances can be in situ converted into toxic agents for cancer *** this review,we systematically summarize the catalytic cancer therapy based on different types of external physical fields,including light,ultrasound,electricity,temperature,X-ray,magnetic field,and *** properties,mechanisms,and advantages of the corresponding external physical fields in cancer therapy are also ***,considering the rapid development of catalytic nano-medicine,the research progress of catalytic cancer therapy driven by external physical fields is ***,the remaining challenges and outlooks that catalytic cancer therapy faced are also *** believe that the emerging external physical fields-driven nanocatalytic cancer therapy will provide a new avenue for cancer treatment.

关键词： biomaterial cancer therapy external physical field nanocatalytic medicine

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同时性:“绵延”的“瞬间”向度

世界哲学 2019年第3期 110-120页

作者：吴清原中国社会科学院研究生院

1922年,柏格森发表了《绵延与同时性》,并于同年4月与爱因斯坦就同时性问题展开了关于"哲学时间"与"物理时间"的对面交锋。在此后的近十年间,柏格森修订并多次再版了这部著作,但由于其内容一再遭到读者的误解,他最终决意终止出版。由此... 详细信息

1922年,柏格森发表了《绵延与同时性》,并于同年4月与爱因斯坦就同时性问题展开了关于"哲学时间"与"物理时间"的对面交锋。在此后的近十年间,柏格森修订并多次再版了这部著作,但由于其内容一再遭到读者的误解,他最终决意终止出版。由此,《绵延与同时性》的内容逐渐为大众所遗忘,而它对于柏格森本人的思想,及其对于哲学语境下时间问题的研究意义,长久以来也遭到了忽视。在重新考察此书内容的过程中,理解作为"瞬间"向度的"同时性",是把握不同于物理时间意义上的真正的时间的核心,也是能够真正把握柏格森毕生所专注的"绵延"概念的钥匙。

关键词：同时性瞬间绵延柏格森