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铋牺牲法制备石墨烯负载Fe-N单原子位点增效氧还原催化和锌-空气电池性能

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Chinese Journal of Catalysis 2024年第4期59卷 272-281页

作者：杨志远张燕肖娟定王俊英王俊中安徽大学物质科学与信息技术研究院安徽石墨烯碳纤维材料工程研究中心安徽合肥230601 中国科学院山西煤炭化学研究所炭材料山西省重点实验室山西太原030001

催化氧反应(ORR)是锌空电池和氢燃料电池能量转化的关键过程,然而其反应速率往往较低,因此开发高活性且耐久的催化材料至关重要.当前,研发低成本、高效率且稳定的氧还原催化剂已成为国内外的研究热点.其中,富含金属-氮-碳活性位点的低成... 详细信息

催化氧反应(ORR)是锌空电池和氢燃料电池能量转化的关键过程,然而其反应速率往往较低,因此开发高活性且耐久的催化材料至关重要.当前,研发低成本、高效率且稳定的氧还原催化剂已成为国内外的研究热点.其中,富含金属-氮-碳活性位点的低成本ORR催化材料,因其具有替代贵金属的潜力,成为重要的候选材料.然而,在制备这类催化剂时,所用分子前驱体在热解过程中易团聚形成金属基硬颗粒,如何减少热解过程中金属成分的自发聚集和不良副产物的生成,提高活性单原子的利用率,特别是在使用廉价分子前驱体(如三聚氰胺和铁盐)时,仍面临挑战.本研究旨在探索有效的制备策略,以优化催化剂性能,推动其在能源转换领域的应用.本文报道了一种以硝酸铋为牺牲剂,石墨烯为导电载体,通过热解廉价的三聚氰胺和铁盐,合成石墨烯负载丰富Fe-N-C活性位点催化剂的新方法.该方法中硝酸铋前驱体高温热解生成的铋铁合金或氧化铋因表面没有碳层,而容易被热酸除去,形成更多的可接近的FeNx活性位点,从而有效地抑制铁基颗粒和管状碳结构的形成,实现了催化剂的高效合成.双球差矫正电镜、X-射线光电子能谱和X-射线吸收结构光谱等表征证明,铋化合物去除后留下空位被铁原子取代,增加了Fe-N-C位点密度,并且铁以单原子活性位形式存在.实验结果表明,所制备的催化剂表现出高氧还原性能,在碱性和酸性条件下的半波电位分别为0.916和0.784 V.石墨烯基催化剂的动力学电流密度(0.9 V vs.RHE)达到10.41 mA cm^(-2),是不加铋化合物样品的6倍,贵金属Pt/C催化剂的4倍.此外,催化剂的塔菲尔斜率为59 mV dec^(-1),低于不加铋化合物样品(80 mV dec^(-1))、不加石墨烯样品(93 mV dec^(-1))、无金属样品(88 mV dec^(-1))和Pt/C(80 mV dec^(-1)).在0.1 mol L^(-1) KOH条件下,催化剂循环10000圈后,半波电位仅衰减15 mV,低于Pt/C(36 mV)和无铋对照样(20 mV),表明催化剂具有较好的稳定性.由于电化学法制备的石墨烯比热解法制备的非晶碳具有更好的耐腐蚀性,从而可以提高阴极氧还原的稳定性.另外,所制备的催化剂应用在锌-空气电池中时,最大功率密度可达201.4 mW cm-2,且循环1000次后电池电压几乎没有衰减.综上,本研究通过引入铋化合物,显著提升了廉价前驱物铁-三聚氰胺的金属单原子化效率.利用电化学法合成了石墨烯负载的Fe-N-C催化活性位,制备出高活性、高稳定的催化剂.将该低成本催化剂应用于锌-空气电池的阴极,其表现出良好的长循环性能.本研究为制备低成本、高性能的金属-氮-碳基电催化剂提供了新思路.

关键词：氧还原反应铋石墨烯锌-空气电池 Fe-N-C

Biphasic Mechanical Properties of in vivo Repaired Cartilage

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Journal of Bionic Engineering 2015年第3期12卷 473-482页

作者： Qin Lian Cheng Chen Marie Chantal Uwayezu Weijie Zhang Weiguo Bian junzhong wang Zhongmin Jin State Key Laboratory for Manufacturing Systems Engineering Xi 'an Jiaotong University Xi 'an 710054 China Orthopaedics Department First Affiliated Hospital Xi 'an Jiaotong University Xi 'an 710061 China Institute of Medical and Biological Engineering School of Meehanical Engineering University of Leeds Leeds LS2 9JT UK

In the fast growing field of scaffold-based tissue engineering, improvement on the mechanical properties of newly formed tissues, e.g. the repaired cartilage, has always been one of the core issues. Studies on the correlations among scaffold composition, in vivo morphological changes of the construct, and the finite deformation behaviors of new tissues （e.g. creep and stress-relaxation, and equilibrium response）, have attracted increasing interests. In this paper, the correlations between the compressive biphasic mechanical properties （i.e., equilibrium elastic modulus E and permeability coefficient k） of 3D printing scaffold （consisting of collagen and fl-tricalcium phosphate） and the proteoglycans （PGs） concentration of the repaired carti- lages after 24 weeks, 36 weeks and 52 weeks of scaffold implantation were investigated. Results indicated that the repaired cartilage covered the entire cartilage surface of large cylindrical osteochondral defects （10 mm in diameter ~ 15 mm in depth） on the canine trochlea grooves after 24 weeks. The equilibrium elastic modulus of the repaired cartilage reached 22.4% at 24 weeks, 70.3% at 36 weeks, and 93.4% at 52 weeks of the native cartilage, respectively. Meanwhile, the permeability coefficient decreased with time and at 52 weeks was still inferior to that of the native cartilage in one order of magnitude. In addition, the amount of glycosaminoglycans （GAGs） of repaired cartilage increased constantly with time, which at 52 weeks approached to nearly 60% of that of native cartilage. 3D printed scaffolds have potential applications in repairing large-scale cartilage defects.

关键词： biphasic mechanical properties PGs repaired cartilage osteochondral scaffolds 3D printing

Epitaxial growth of ultrathin gallium films on Cd(0001)

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Chinese Physics B 2024年第1期33卷 722-727页

作者：李佐石明霞姚钢陶敏龙王俊忠 School of Physical Science and Technology Southwest UniversityChongqing 400715China School of Science Guizhou University of Engineering ScienceBijie 551700China

Growth and electronic properties of ultrathin Ga films on Cd(0001) are investigated by low-temperature scanning tunneling microscopy(STM) and density functional theory(DFT) calculations. It is found that Ga films exhibit the epitaxial growth with the pseudomorphic 1×1 lattice. The Ga islands deposited at 100 K show a ramified shape due to the suppressed edge diffusion and corner crossing. Furthermore, the majority of Ga islands reveal flat tops and a preferred height of three atomic layers, indicating the electronic growth at low temperature. Annealing to room temperature leads to not only the growth mode transition from electronic growth to conventional Stranski–Krastanov growth, but also the shape transition from ramified islands to smooth compact islands. Scanning tunneling spectroscopy(STS) measurements reveal that the Ga monolayer exhibits metallic behavior. DFT calculations indicate that all the interfacial Ga atoms occupy the energetically favorable hcp-hollow sites of the substrate. The charge density difference analysis demonstrates that the charge transfer from the Cd substrate to the Ga atoms is negligible, and there is weak interaction between Ga atoms and the Cd substrate. These results shall shed important light on fabrication of ultrathin Ga films on metal substrates with novel physical properties.

关键词： gallium films electronic growth STM/STS density functional theory

Hydrological Problem during Urbanization Process

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Meteorological and Environmental Research 2013年第11期4卷 16-21页

作者： Nanzhu Li junzhong wang Tianyou Yuan School of Economics Henan University The Soil and Fertilizer Station Henan Agriculture Department

With the rapid economic and social development, China is in rapid development period of urbanization now. Urbanization is an inevitable trend of mankind development, and is also a necessary stage of a country moving toward modernization. The rapid development of urbanization has a major impact on urban hydrology. Urban hydrologic environment, hydrologic element, water resources and water quality were discussed in the pa- per. Based on the analysis of urban hydrological effect, from the angles of subject development and application, corresponding countermeasures and outlook of the urban hydrology problem were put forward. The research can provide support for reasonably planning and designing urban flood control and drainage systems to promote urban environment-friendly development, having certain practical significance.

关键词： Urbanization Urban hydrology Hydrologic effect Urban water resources China

Atomic metal/Graphene-based electrocatalysts

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Atomic metal/Graphene-based electrocatalysts

Amorphous Cu^0 on Carbon Nanofiber as Recyclable Heterogeneous Catalyst for N-Arylation Reactions

中国化学会第三届中国能源材料化学研讨会

作者： junzhong wang Junying wang CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of Sciences

Interestingly,graphene electrocatalysts can be produced by electrochemical approaches.In this talk,I will present that electrochemically-exfoliated graphene flakes and their atomic hybrids can exhibit high performance...

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Chemical Research in Chinese Universities 2019年第2期35卷 256-260页

作者： wang junzhong LI Hengyu ZHANG Dongdong BAI Jie Chemical Engineering College Inner Mongolia University of TechnologyHohhot 010051P.R.China

A novel heterogeneous catalyst,amorphous Cu^0 on the carbon nanofibers was developed and characte-rized by means of several characterization techniques.The prepared Cu^0 was investigated as a heterogeneous catalyst for N-arylation reaction.The results show it is an excellent catalyst with recyclability,high consistency and catalytic activity.After the catalyst was used for 5 cycles in the N-arylation reaction,amorphous Cu^0 reunited into crystalline copper nanoparticles with different particle sizes and its good heterogeneity in the catalytic system was confirmed after the catalyst recovery.

关键词： Amorphous Cu Carbon nanofiber N-Arylation reaction

发热伴血小板减少综合征发病机制及诊疗研究进展

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中国病毒病杂志 2024年第2期14卷 189-195页

作者：迪丽胡玛尔·扎衣尔张斌朱彬田进黄红明张诗雨王俊忠郑昕王宝菊华中科技大学同济医学院附属协和医院感染性疾病科湖北武汉430022

发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome,SFTS)是由发热伴血小板减少综合征病毒(severe fever with thrombocytopenia syndrome virus,SFTSV),又称大别班达病毒(Dabie bandavirus,DBV)感染所致的急性蜱媒传染病。SFTSV能够影响天然免疫和获得性免疫中的多种免疫细胞,通过细胞因子和趋化因子的释放,使机体产生发热、血小板减少、白细胞减少、器官功能损害等,甚至导致多器官衰竭而造成患者死亡。尽管目前临床上暂无针对SFTSV的具有确切疗效的抗病毒药,但积极的支持对症治疗仍能挽救大部分SFTS患者的生命。为进一步了解SFTS,并探讨有效的SFTS诊疗手段,本文针对其发病机制及最新诊疗进展予以综述。

关键词：发热伴血小板减少综合征发热伴血小板减少综合征病毒新型布尼亚病毒大别班达病毒发病机制治疗

Carrimycin ameliorates lipopolysaccharide and cecal ligation and puncture-induced sepsis in mice

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Chinese Journal of Natural Medicines 2024年第3期22卷 235-248页

作者： LAI junzhong LIANG Jiadi CHEN Kunsen GUAN Biyun CHEN Zhirong CHEN Linqin FAN Jiqiang ZHANG Yong LI Qiumei SU Jingqian CHEN Qi LIN Jizhen The Cancer Center Fujian Medical University Union HospitalFuzhou 350001China Fujian Key Laboratory of Innate Immune Biology Biomedical Research Center of South ChinaFujian Normal UniversityFuzhou 350117China The Department of Otolaryngology Head&Neck SurgeryUniversity of Minnesota Medical SchoolMinneapolisMN 55455USA

Carrimycin(CA),sanctioned by China’s National Medical Products Administration(NMPA)in 2019 for treating acute bronchitis and sinusitis,has recently been observed to exhibit multifaceted biological activities,encompassing anti-inflammatory,antiviral,and anti-tumor properties.Despite these applications,its efficacy in sepsis treatment remains unexplored.This study introduces a novel function of CA,demonstrating its capacity to mitigate sepsis induced by lipopolysaccharide(LPS)and cecal ligation and puncture(CLP)in mice models.Our research employed in vitro assays,real-time quantitative polymerase chain reaction(RT-qPCR),and RNA-seq analysis to establish that CA significantly reduces the levels of pro-inflammatory cytokines,namely tumor necrosis factor-alpha(TNF-α),interleukin 1 beta(IL-1β),and interleukin 6(IL-6),in response to LPS stimulation.Additionally,Western blotting and immunofluorescence assays revealed that CA impedes Nuclear Factor Kappa B(NF-κB)activation in LPS-stimulated RAW264.7 cells.Complementing these findings,in vivo experiments demonstrated that CA effectively alleviates LPS-and CLP-triggered organ inflammation in C57BL/6 mice.Further insights were gained through 16S sequencing,highlighting CA’s pivotal role in enhancing gut microbiota diversity and modulating metabolic pathways,particularly by augmenting the production of short-chain fatty acids in mice subjected to CLP.Notably,a comparative analysis revealed that CA’s anti-inflammatory efficacy surpasses that of equivalent doses of aspirin(ASP)and TIENAM.Collectively,these findings suggest that CA exhibits significant therapeutic potential in sepsis treatment.This discovery provides a foundational theoretical basis for the clinical application of CA in sepsis management.

关键词： Carrimycin Inflammation Lipopolysaccharide Cecal ligation and puncture Sepsis Gut microbiota

Rapamycin modulates the course of hepatitis B virus(HBV)infection in hydrodynamic injection mouse model:the role of Treg in HBV persistence

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Rapamycin modulates the course of hepatitis B virus(HBV)infe...