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Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection

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International Journal of Extreme Manufacturing 2024年第1期6卷 296-311页

作者： Cijun Shuai Xiaoxin Shi feng Yang haifeng Tian Pei feng State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083People’s Republic of China Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013People’s Republic of China College of Mechanical Engineering Xinjiang UniversityUrumqi 830017People’s Republic of China

Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe *** this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser *** results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant *** accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative *** antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(***)and Gram-positive Staphylococcus aureus(***).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation.

关键词： bacterial infection bone scaffold selective laser sintering Fenton reaction antibacterial properties

一种具备谱学功能的扫描隧道显微镜实验装置设计与教学应用

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实验技术与管理 2024年第6期41卷 151-156页

作者：张靖伟龚梓鑫崔丹丹冯海凤郝维昌杜轶北京航空航天大学物理学院北京100191

该文研制了一种具备谱学功能的扫描隧道显微镜实验教学装置。装置采用紧凑的对称式结构设计和高刚性材料,具有漂移小、噪声低的优点,结合减震隔音设计,能够在课堂环境下稳定实现对多种材料表面的原子分辨成像。隧道电流的一阶微分谱直... 详细信息

该文研制了一种具备谱学功能的扫描隧道显微镜实验教学装置。装置采用紧凑的对称式结构设计和高刚性材料,具有漂移小、噪声低的优点,结合减震隔音设计,能够在课堂环境下稳定实现对多种材料表面的原子分辨成像。隧道电流的一阶微分谱直接反映了样品表面的电子态密度信息,可以帮助学生理解隧道电流信号。该装置集成了锁相放大功能,可以实现隧道电流-偏压谱及其一阶微分谱的测量,拓展了扫描探针显微实验的教学内容和教学深度。

关键词：扫描隧道显微镜扫描隧道谱近代物理实验

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Asymmetric Hydrogenation of Phenanthridines with Chiral Boranes

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Chinese Journal of Chemistry 2024年第6期42卷 631-635页

作者： Guangyu Cui Xiangqing feng haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

The asymmetric hydrogenation of N-heteroarenes provides an efficient method for the synthesis of optically active cyclic secondary *** this paper,we described an asymmetric hydrogenation of phenanthridines using a chiral mono-alkene-derived borane.A variety of dihydrophenanthridines were furnished in high yields with up to 93%*** current catalytic system was very sensitive for the steric hindrance of *** substituents at one phenyl group of phenanthridines were required to obtain the high *** large substituents on the carbon of the C=N bonds would diminish the reactivity sharply.

关键词： Asymmetric catalysis Hydrogenation Nitrogen heterocycles Phenanthridines Frustrated Lewis pairs Chiral boranes

Asymmetric Partial Hydrosilylation of 2,2-Difluoro-1,3-diketones with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2024年第8期42卷 853-857页

作者： Ting Liu Xiangqing feng haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary,The asymmetric partial reduction of 1,3-diketones stands as a straightforward pathway to access optically active β-hydroxyketones. In this paper, an asymmetric Piers-type hydrosilylation of 2,2-difluoro-1,3-diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α-difluoro-β-hydroxyketones in high yields with up to 99% ee. Significantly, no over-reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α-difluoro-β-hydroxyester or 1,3-anti-diol via an oxidation with m-CPBA or a reduction with DIBAL-H without obvious loss of ee.

关键词： Asymmetric catalysis Hydrosilylation Ketones Frustrated Lewis pairs Chiral boranes

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拖网渔船导缆孔支撑结构强度分析

船舶标准化工程师 2024年第2期57卷 15-19页

作者：冯海峰孙旭明金颂雨管官黄海造船有限公司山东威海264309 大连理工大学船舶工程学院辽宁大连116024

为确保某双甲板拖网渔船导缆孔强度满足相关规范要求,防止由于支撑结构强度不足而导致船体结构被破坏,使用有限元方法对艉部导缆孔及其支撑结构进行仿真计算,并将计算结果与相关规范进行比较,进而确定支撑结构的高应力区域。此外,针对... 详细信息

为确保某双甲板拖网渔船导缆孔强度满足相关规范要求,防止由于支撑结构强度不足而导致船体结构被破坏,使用有限元方法对艉部导缆孔及其支撑结构进行仿真计算,并将计算结果与相关规范进行比较,进而确定支撑结构的高应力区域。此外,针对现有船体结构强度不满足规范要求的问题,结合拖网渔船艉部系泊设备的布置特点,为艉部增设内舷墙结构。研究表明:增强方案合理有效,可确保导缆孔支撑结构强度满足规范要求。研究成果可为拖网渔船导缆孔支撑结构设计提供一定参考。

关键词：导缆孔支撑结构有限元方法局部结构强度

Efficient ammonia electrosynthesis from nitrate via a three-step relay mechanism

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Science China Chemistry 2024年第1期67卷 319-320页

作者： haifeng Jiang Gao-feng Chen Haihui Wang Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Colloid Chemistry Max-Planck Institute of Colloids and InterfacesPotsdam 14476Germany School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China

Electrocatalytically converting nitrate waste to value-added ammonia(NO3−RR)is beneficial to environmental restoration and an attractive candidate for green ammonia production[1].However,developing NO_(3)^(-)RR in an energy-saving way remains a significant challenge due to the slow kinetics inherent in multi-step electron and proton transfer,making previous investigations for NO_(3)^(-)RR generally operate at a large overpotential(<-0.2 V versus reversible hydrogen electrode(RHE))to achieve optimal efficiency and industrial current for NH3 synthesis[2].

关键词： ammonia nitrate kinetics

A novel splicing variant in the TMC1 gene causes non-syndromic hearing loss in a Chinese family

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Chinese Medical Journal 2022年第21期135卷 2631-2633页

作者： Beiping Zeng Hongen Xu Yongan Tian Qianyu Lin haifeng feng Zhifeng Zhang Siqi Li Wenxue Tang BGI College and Henan Institute of Medical and Pharmaceutical Sciences Zhengzhou UniversityZhengzhouHenan 450052China Precision Medicine Center Academy of Medical ScienceZhengzhou UniversityZhengzhouHenan 450052China The Second Affiliated Hospital of Zhengzhou University ZhengzhouHenan 450014China Department of Otorhinolaryngology Head and Neck SurgeryThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China The Third People’s Hospital of Zhengzhou ZhengzhouHenan 450000China Department of Physiology and Neurobiology Academy of Medical ScienceZhengzhou UniversityZhengzhouHenan 450001China

To the Editor:Hearing loss is the most common sensory disorder in *** is one case of congenital deafness among every 1000 newborns,and in 50%of cases,the deafness is *** exhibits high genetic *** date,over 110 non-syndromic deafness genes have been identified(https://***/).Lots of those genes can cause both autosomaldominant hearing loss(ADNSHL)and autosomal-recessive non-syndromic hearing loss(ARNSHL)andTMC1(encoding the transmembrane channel-like 1)is one of ***1(OMIM:606706)is a member of the TMC family located at *** protein contains 760 amino acids and has six transmembrane ***1 is expressed in the inner and outer hair cells of the cochlea.A TMC1 mutation was first shown to cause deafness in 2002.[1]The prevalence of TMC1 variants ranged from 3.4%(19/557)among Pakistani ARNSHL families to 8.1%(7/86)in Turkish *** date,around 20 hearing loss families associated withTMC1 variants have been reported in China.

关键词： deafness congenital hearing

Rising utilization of stable isotopes in tree rings for climate change and forest ecology

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Journal of Forestry Research 2024年第1期35卷 103-116页

作者： Ru Huang Chenxi Xu Jussi Grießinger Xiaoyu feng haifeng Zhu Achim Bräuning National Institute of Natural Hazards Beijing 100085People’s Republic of China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People’s Republic of China Institute of Geography Friedrich-Alexander-University of Erlangen-Nuremberg91058 ErlangenGermany State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary *** rapid development in this field documented in an increasing number of publications requires a comprehensive *** study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope ***,1475 publications were selected from the Web of Science Core Collection for *** findings are that:(1)numbers of annual publications and citations increased since *** 1974 to 1980,there were around two relevant publications per ***,from 2020 to 2022,this rose sharply to 109 publications per ***,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular *** 2010,precipitation and drought have received increasing *** on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are *** study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

关键词： Tree rings Stable isotopes Web of Science Bibliometric

Nanoscopic tribological characteristics of a cryogenically cycled Zr-based metallic glass

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 113-126页

作者： Qian Jia Qiaosheng Xia Qing Zhou Yucheng Wang Yue Ren Yu Meng haifeng Wang feng Zhou State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Surface Engineering and Remanufacturing Xi’an UniversityXi’an 710065China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Optimized macroscopic tribological behavior can be anticipated in metallic glasses(MGs)by cryogenic cycling treatment(CCT),which is attributed to enhanced ***,the intrinsic friction mechanisms of MGs induced by cryogenic rejuvenation are still poorly *** the present study,nanoscopic wear tests were conducted on the Zr-based MGs surface with different CCT cycles using atomic force microscopy(AFM).After CCT treatment with 100 cycles,the MG displays the highest adhesion and ploughing frictions,but significantly improved anti-wear *** tests and molecular dynamics simulations disclose that the increased adhesion is attributed to the dominance of liquid-like regions in the CCT-treated MGs,and the impact of reduced hardness and weak elastic recovery results in the deteriorated ploughing *** enhanced plasticity effectively dissipates the strain from the AFM tip through multiple shear bands and weakens the adhesion during deformation,giving rise to excellent wear *** study elucidates the promoting effect of CCT on the outstanding antiwear performance of MGs,and is helpful for the development of novel alloys.

关键词： metallic glasses cryogenic cycling treatment nanoscope wear friction mechanism

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