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RESEARCH PROGRESS ON STRUCTURAL FATIGUE RELIABILITY DESIGN AND ANALYSIS METHODS OF CHINESE RAILWAY VEHICLES

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Chinese Journal of Mechanical Engineering 2007年第4期20卷 79-83页

作者： zhao yongxiang PENG Jiachun YANG Bing Traction Power State Key Laboratory Southwest Jiaotong University Chengdu 610031 China

A state-of-art review is given to the new advances on fatigue reliability design and analysis methods of Chinese railway vehicle＇s structures. First, the structures are subject to a complicated random fatigue stressing history and this history should be determined by combining dynamic simulation and on-line inspection. Second, the random fatigue constitutions belong to an intrinsic fatigue phenomenon and a probabilistic model is developed to well describe them with two measurements of survival probability and confidence, similar model is also presented for the random stress-life rela- tions and extrapolated appropriately into Song fatigue life regime. Third, concept of the fatigue limit should be understood as the fatigue strength at a given fatigue life and a so-called local Basquin model method is proposed for measuring the random strengths. In addition, drawing and application methods of the Goodman-Smith diagram for integrally characterizing the random fatigue strengths are established in terms of ten kilometers. Fourth, a reliability stress-based method is constructed with a consideration of the random constitutive relations. These new advances form a new frame work for railway fatigue reliability design and analysis.

关键词： Railway vehicle Fatigue Reliability Design Life prediction Assessment

How time latency in navigation Apps affects traffic

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The Journal of China Universities of Posts and Telecommunications 2022年第6期29卷 53-63页

作者： Yang Jingjing Guo Yuchun zhao yongxiang Chen Yishuai School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

With the recent increase in routing App usage, it is urgent to analyze the impact of inevitable information delay in routing Apps on *** analyze the negative impact of such delayed routing Apps on traffic, this paper investigates the impact of ideal and delayed routing Apps on traffic. Firstly, the effect of ideal routing Apps has been explored with theoretical analysis and derivation based on a macroscopic network model. Then, an extended network model is built to characterize the delayed *** impact of such delayed routing Apps is investigated by simulation experiments while considering routing usage proportion and amount of delay. The results demonstrate that ideal navigation does improve traffic efficiency, but in some cases, delayed navigation is even worse than no navigation.

关键词： traffic network delayed routing system performance

Effects of polydopamine modification on self-grown Cu O cube anodes in lithium-ion batteries

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Science China(Technological Sciences) 2016年第4期59卷 667-672,1-4页

作者： HAO LiHua WU LiQiong JIA ZhiQi zhao yongxiang LI XinHeng College of Chemistry and Chemical Engineering Shanxi University State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP)

We report the synthesis of Cut cubes with well-defined size and shape by thermal treatments of Cu2O cubes. Polydopamine （PDA） is introduced to modify the Cut cubes by the in-situ polymerization of the dopamine precursor. The initial specific ca- pacity of the lithium-ion batteries using the Cut cubes as anodes increases about 10 times at a 0.5 C rate as a result of the modification of PDA. The overall specific capacity for 100 cycles also increases effectively due to the introduction of PDA. So PDA as surface modifying agent significantly improves the electrochemical performance of the Cut anodes.

关键词： lithium anode materials copper oxides polydopamine modification specific capacity in-situ polymerization

Comparative Studies of Non-noble Metal Modified Mesoporous M-Ni-CaO-ZrO2 （M=Fe, Co, Cu） Catalysts for Simulated Biogas Dry Reforming

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Chinese Journal of Chemistry 2017年第1期35卷 113-120页

作者： Changzhen Wang Yin Zhang Yongzhao Wang yongxiang zhao Engineering Research Center of Ministry of Education for Fine Chemicals Shanxi University Taiyuan Shanxi 030006 China

The present work is aimed to improve the performance of Ni-based catalysts for biogas dry reforming by adding a second non-noble metal （Fe, Co, Cu） into a previously studied mesoporous Ni-CaO-ZrO2 nanocomposite. Biogas was simulated with equivalent methane and carbon dioxide for the dry reforming reaction. X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, N2 adsorption, temperature-programmed reduction （TPR）, thermogravi- metric analysis （TGA）, and transmission electron microscopy （TEM） measurements were taken to characterize the structural and textual properties of the bimetallic catalysts as well as the accumulated carbon deposition. The addition of Fe leads to a less ordering growth of mesopores of Fe-Ni-CaO-ZrO2 sample, and the existence of Cu results in a relatively larger portion of free NiO in Cu-Ni-CaO-ZrO2. Compared with Fe and Cu, the presence of Co could efficiently form a beneficial dual metal effect and enhance the strong metal support interaction between Ni and CaO-ZrO2, thus enhancing the activity and stability of the catalyst in biogas dry reforming reaction.

关键词： nickel catalyst non-noble metal modified bimetallic catalyst biogas dry reforming carbon deposition

Fluorine Modified TAPO-5： Synthesis and Catalytic Performance in Cyclohexanone Ammoximation

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Chemical Research in Chinese Universities 2018年第2期34卷 247-253页

作者： LI Hengjie GAO Pengfei XUE Xiaolu ZHANG Hongxi zhao yongxiang School of Chemistry and Chemical Engineering Engineering Research Centre of Ministry of Education for Fine Chemicals Shanxi University Taiyuan 030006 P. R. China

A series of fluorine modified TAPO-5 molecular sieves was synthesized by one-pot method using ammo- nittm hexafluorotitanate as titanium and fluorine sources. The XPS and DRS UV-Vis results indicated that the exis- tence of F could promote the formation of tetrahedrally coordinated framework Ti and A1, meanwhile, inhibit the formation of anatase TiO2 in TAPO-5 sieves due to the unique role ofF in the sol-gel process of metal ions. Further- more, TG, contact angle test, Py-FTIR and 27A1 MAS NMR results revealed that fluorine modification increased the surface hydrophobicity and the Lewis acidity of Ti active sites through forming AlxFy units in the neighborhood. All these factors make these fluorine modified TAPO-5 sieves exhibit good catalytic performance in the arnmoximation of cyclohexanone.

关键词： TAPO-5 Fluorine modification Hydrophobicity Lewis acidity Cyclohexanone ammoximafion

Review:Development of SARS-CoV-2 immuno-enhanced COVID-19 vaccines with nano-platform

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Nano Research 2022年第3期15卷 2196-2225页

作者： Nawamin Sa-nguanmoo Katawut Namdee Mattaka Khongkow Uracha Ruktanonchai yongxiang zhao Xing-Jie Liang CAS Center for Excellence in Nanoscience CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyNational Center for Nanoscience and Technology of ChinaBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Nanotechnology Center(NANOTEC) National Science and Technology Development AgencyPathum Thani 12120Thailand National Center for International Research of Biotargeting Theranostics Guangxi Key Laboratory of Biotargeting TheranosticsCollaborative Innovation Center for Targeting Tumour Theranostics and TherapyGuangxi Medical UniversityNanning 530021China

Vaccination is the most effective way to prevent coronavirus disease 2019(COVID-19).Vaccine development approaches consist of viral vector vaccines,DNA vaccine,RNA vaccine,live attenuated virus,and recombinant proteins,which elicit a specific immune *** use of nanoparticles displaying antigen is one of the alternative approaches to conventional *** is due to the fact that nano-based vaccines are stable,able to target,form images,and offer an opportunity to enhance the immune *** diameters of ultrafine nanoparticles are in the range of 1–100 *** application of nanotechnology on vaccine design provides precise fabrication of nanomaterials with desirable properties and ability to eliminate undesirable *** be successful,nanomaterials must be uptaken into the cell,especially into the target and able to modulate cellular functions at the subcellular *** advantages of nano-based vaccines are the ability to protect a cargo such as RNA,DNA,protein,or synthesis substance and have enhanced stability in a broad range of pH,ambient temperatures,and humidity for long-term ***,nano-based vaccines can be engineered to overcome biological barriers such as nonspecific distribution in order to elicit functions in antigen presenting *** this review,we will summarize on the developing COVID-19 vaccine strategies and how the nanotechnology can enhance antigen presentation and strong immunogenicity using advanced technology in nanocarrier to deliver *** discussion about their safe,effective,and affordable vaccines to immunize against COVID-19 will be highlighted.

关键词： COVID-19 SARS-CoV-2 vaccine nanotechnology antigen presenting cells(APCs)

The nature of the deactivation of hydrothermally stable Ni/SiO2–Al2O3 catalyst in long-time aqueous phase hydrogenation of crude 1,4-butanediol

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Chinese Journal of Chemical Engineering 2019年第12期27卷 2960-2967页

作者： Haitao Li Yin Zhang Hongxi Zhang Xiaoqin Qin Yalin Xu RuifangWu Zheng Jiang yongxiang zhao Engineering Research Center of Ministry of Education for Fine Chemicals Shanxi UniversityTaiyuan 030006China Faculty of Engineering and the Environment University of SouthamptonSouthampton SO171BJUK

The deactivation of Ni/SiO2-Al2 O3 catalyst in hydrogenation of crude 1,4-butanediol was *** the operation time of 2140 h,the catalyst showed slow activity *** results,for four spent catalysts used at different time,indicated that the main reason of the catalyst deactivation was the deposition of carbonaceous species that covered the active Ni and blocked mesopores of the *** TPO and SEM measurements revealed that the carbonaceous species included both oligomeric and polymeric species with high C/H ratio and showed *** carbonaceous species might be eliminated through either direct H2 reduction or the combined oxidation-reduction methodologies.

关键词： 1,4-Butanediol Hydrogenation Ni/SiO2–Al2O3 catalyst Deactivation Regeneration

Boron difluoride formazanate dye for high-efficiency NIR-Ⅱ fluorescence imaging-guided cancer photothermal therapy

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Chinese Chemical Letters 2022年第5期33卷 2501-2506页

作者： Hanming Dai Zijin Cheng Tian Zhang Weili Wang Jinjun Shao Wenjun Wang yongxiang zhao Xiaochen Dong Liping Zhong Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing 211800China School of Physical Science and Information Technology Liaocheng UniversityLiaocheng 252059China National Center for International Biotargeting Theranostics Guangxi Key Laboratory of Biotargeting TheranosticsCollaborative Innovation Center for Targeting Tumor TheranosticsGuangxi Medical UniversityNanning 530021China

The small molecular second near-infrared(NIR-Ⅱ, 1000–1700 nm) dye-based nanotheranostics can concurrently combine deep-tissue photodiagnosis with in situ phototherapy, which occupies a vital position in the early detection and precise treatment of tumors. However, the development of small molecular NIR-Ⅱ dyes is still challenging due to the limited electron acceptors and cumbersome synthetic ***, we report a novel molecular electron acceptor, boron difluoride formazanate(BDF). Based on BDF, a new small molecular NIR-Ⅱ dye BDF1005 is designed and synthesized with strong NIR-I absorption at 768 nm and bright NIR-Ⅱ peak emission at 1034 nm. In vitro and in vivo experiments demonstrate that BDF1005-based nanotheranostics can be applied for NIR-Ⅱ fluorescence imaging-guided photothermal therapy of 4T1 tumor-bearing mice. Under 808 nm laser irradiation, tumor growth can be effectively inhibited. This work opens up a new road for the exploitation of NIR-Ⅱ small molecular dyes for cancer phototheranostics.

关键词： NIR-II nanotheranostics Boron difluoride formazanate Fluorescence imaging Photothermal therapy Phototheranostics

Identification of SARS-CoV-2-against aptamer with high neutralization activity by blocking the RBD domain of spike protein 1

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Signal Transduction and Targeted Therapy 2021年第7期6卷 1985-1988页

作者： Ge Yang Ziyue Li Irfan Mohammed Liping zhao Wei Wei Haihua Xiao Weisheng Guo yongxiang zhao Feng Qu Yuanyu Huang School of Life Science Advanced Research Institute of Multidisciplinary ScienceInstitute of Engineering MedicineKey Laboratory of Molecular Medicine and BiotherapyBeijing Institute of TechnologyBeijingChina State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijingChina Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijingChina Translational Medicine Center Key Laboratory of Molecular Target&Clinical Pharmacology and the State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences&the Second Affiliated HospitalGuangzhou Medical UniversityGuangzhouChina National Center for International Research of Biological Targeting Diagnosis and Therapy Guangxi Key Laboratory of Biological Targeting Diagnosis and Therapy ResearchGuangxi Medical UniversityNanningGuangxiChina

Dear Editor,The ongoing outbreak of coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)poses a great threat to the public health of people and the normal economic and social development around the *** of January 8,2021,more than 88 million people were infected with SARS-CoV-2,resulting in more than 1.9 million death.

关键词： death acute respiratory