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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin Li mengmeng Xie Jingyu Li Nana Shen Xinying Zhang Xuesen fan State Key Laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-dione.When the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]spirocyclization.When the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen source.In general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3,1'-isoindolinones 3d Transition metals Cobalt-catalyzed C-H Activation Switchable[4+1]and[4+1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3(2H)-dione

DNA Nanostructure-Guided Plasmon Coupling Architectures

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CCS Chemistry 2023年第3期5卷 568-588页

作者： mengmeng Liu Xiaoyu Zhang Lulu Huang Jie Li Chunhai fan Yang Tian Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200241 School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesInstitute of Translational MedicineShanghai Jiao Tong UniversityShanghai 200240

Plasmon coupling architectures with specific spatial and orientational arrangement configurations possess unique and tailored plasmonic properties and hold promise for advancements in nano-optics,nanoantennas,and biosensors.Numerous research has focused on the construction of plasmonic assemblies with predetermined configurations.DNA nanostructures with arbitrary geometry,high compatibility with metal nanoparticles,and spatial addressability meet the requirement for precise spatial and orientation arrangement.Currently,DNA nanostructures are widely exploited as structural materials to generate plasmonic structures with well-defined topologies.We review the evolution of DNA nanostructureguided plasmon coupling architectures,including the introduction of DNA nanostructures,DNA modification on the surface of plasmonic nanoparticles,and three strategies for constructing complex plasmonic nanostructures.Then we focus on the emerging applications of DNA nanostructure-guided architectures with engineered local electromagnetic enhancement for modulating plasmon coupling,amplifying emitter signals,and serving as biosensors.Finally,we will critically discuss the challenges and opportunities in this field.

关键词： DNA nanostructures plasmonic nanoparticles localized surface plasmon resonance plasmon coupling architectures

Strength criterion effect of the translator and destabilization model of gas-bearing coal seam

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International Journal of Mining Science and Technology 2019年第2期29卷 327-333页

作者： Gang Wang Rui Wang mengmeng Wu Cheng fan Xiang Song Mine Disaster Prevention and Control-Ministry of State Key Laboratory Breeding Base Shandong University of Science & Technology College of Mining and Safety Engineering Shandong University of Science & Technology Department of Civil and Architectural Engineering City University of Hong Kong

Coal seam destabilization inflicts damage to equipment, causes property loss and personnel casualties,and severely threatens mining safety and efficient production. To further understand this destabilization based on the basic theory of Lippmann seam destabilization, a mathematical model was introduced for gas pressure distribution by considering intermediate principal stress and support resistance.Subsequently, we established a translation model suitable for the entire roadway coal seam with rocky roof and floor by applying the unified form of yield criterion in the state of plane strain. We also obtained the analytic expressions of coal seam stress distribution on both sides of the roadway and the widths of plastic and disturbance zones. Afterward, we analyzed several typical cases with different material yield criteria, obtained the plastic zone widths of the coal seam under different gas pressures, and assessed the effects of support resistance, roadway size, and coal strength on coal seam destabilization. Results showed that: the results obtained on the basis of Wilson and Mohr–Coulomb criteria are considerably conservative, and the use of Druker–Prager criteria to evaluate the rockburst-induced coal seam destabilization is safer than the use of the two other criteria; coal seam stability is correlated with gas pressure;and high-pressure gas accelerates the coal seam destabilization.

关键词： Coal seam destabilization Strength criterion effect Gas Stress distribution

Effect of strawberry vein banding virus and strawberry mottle virus co-infection on the growth and development of strawberry

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BIOCELL 2022年第1期46卷 263-273页

作者： LINGJIAO fan DAN SONG YINGWEI KHOO mengmeng WU TENGFEI XU XIAOLI ZHAO HONGQING WANG College of Horticulture China Agricultural UniversityBeijing100193China State Key Laboratory of Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China

Strawberry mottle virus(SMoV)and strawberry vein banding virus(SVBV)cause diseases on strawberry plants,but the effect of coinfection of SMoV and SVBV on the growth,development,and defense system of strawberry(Fragaria×ananassa Duchesne)remains unknown.We investigated the effect of SMoV and SVBV coinfection on strawberry cultivar‘Benihope’.The results showed that stem diameter,leaf size,leaf number,relative chlorophyll content,total chlorophyll content,photosynthetic parameters,and stomatal aperture of SMoV and SVBV co-infected strawberry(VIS)plants were in a weaker level than uninfected control plants,indicating that viruses inhibited the growth and photosynthesis of strawberry plants.Furthermore,the initiation of flowering and fruiting stages of VIS plants were delayed by about three weeks compared with the controls,and the fruiting period was shortened,demonstrating that the reproduction of VIS plants was inhibited.Fruit quality was damaged in VIS plants due to a significant increase in fruit firmness and titratable acidity and decrease in total soluble solid content than control fruits.More dead cells and H_(2)O_(2) accumulated along the veins of VIS leaves,and the content of abscisic acid and catalase activity significantly increased,whereas anthocyanin content was lower than that of control plants.The results demonstrate that SVBV and SMoV coinfection inhibits the growth and development of‘Benihope’strawberry plants,and the plants respond to viruses by regulating stomatal aperture,the accumulation of ABA and antioxidants.To our knowledge,this study contributes information to understand how both viruses impair the strawberry growth and development for the first time.

关键词： Photosynthesis Flowering and fruiting period Antioxidants Plant defense

Fabricating pyridinic N-B sites in porous carbon as efficient metal-free electrocatalyst in conversion CO_(2)into CH_(4)

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中国化学快报:英文版 2023年第8期34卷 291-295页

作者： Yuying Zhao Qixin Yuan Mengmeng Fan Ao Wang Kang Sun Zeming Wang Jianchun Jiang Institute of Chemical Industry of Forest Products Chinese Academy of ForestryKey Lab.of Biomass Energy and MaterialJiangsu ProvinceNational Engineering Lab for Biomass Chemical UtilizationNanjing 210042China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and Materials College of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China Institute of Nanochemistry and Nanobiology School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China

Electrochemical reduction of CO_(2)(CO_(2)RR)to value-added chemicals is an attractive strategy for greenhouse gas mitigation and carbon recycle.Carbon material is one of most promising electrocatalysts but its product selectivity is limited by few modulating approaches for active sites.Herein,the predominant pyridinic N-B sites(accounting for 80%to all N species)are fabricated in hierarchically porous structure of graphene nanoribbons/amorphous carbon.The graphene nanoribbons and porous structure can accelerate electron and ion/gas transport during CO_(2)RR,respectively.This carbon electrocatalyst exhibits excellent selectivity toward CO_(2)reduction to CH_(4)with the faradaic efficiency of 68%at−0.50 V vs.RHE.As demonstrated by density functional theory,a proper adsorbed energy of∗CO and∗CH_(2)O are generated on the pyridinic N-B site resulting into high CH_(4)selectivity.Therefore,this study provides a novel method to modulate active sites of carbon-based electrocatalyst to obtain high CH_(4)selectivity.

关键词： Carbon-based electrocatalyst Porous carbon Pyridinic N-B CO_(2)reduction CH_(4)selectivity

Progress of organic magnetic materials

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Science China(Physics,Mechanics & Astronomy) 2019年第7期62卷 22-33页

作者： mengmeng Wei Yingcai fan Wei Qin State Key Laboratory of Crystal Materials School of Physics Shandong University School of Information and Electronic Engineering Shandong Technology and Business University

Over the past years, the development of magnetic materials has been intensively explored, both for fundamental research and technological applications. Particularly, several materials with large magnetoresistance effect have received significant interest.In this study, we provide an analysis of the progress of organic magnetic materials and organic magnetoelectric complexes, thus paving the way for the understanding of organic magnetism and magnetoelectric coupling mechanisms. In addition, this analysis provides us a critical guide for future organic magnetic material design and fabrication.

关键词： organic materials magnetism magnetoelectric coupling effect

Mass Loss Behavior and Volatile Composition during Pyrolysis of a Bituminous Coal

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China Petroleum Processing & Petrochemical Technology 2018年第4期20卷 44-50页

作者： fan Junfeng Tian Bin An Xiaoxi Zhang Yaqing Yin mengmeng Tian Yuanyu College of Chemical and Environmental Engineering Shandong University of Science and Technology Advanced Chemical Technology for Utilization of Northern Shaanxi Energy of the Engineering Research Center of the Ministry of Education Shaanxi Research Center of Engineering Technology for Clean Coal Conversion School of Chemical Engineering Northwest University

The thermogravimetry analyzer coupled with the pyrolysis gas chromatography/time-of-flight mass spectrometry technology was used in this study to investigate the mass loss behavior and volatile release characteristics of a bituminous coal. The results showed that with an increasing heating rate, the characteristic parameters and TG/DTG curves shifted obviously to the higher temperature region. The pyrolysis of a bituminous coal at different heating rates can be divided into two stages according to the Coats-Redfern(C-R) plots. The activation energy obtained from the C-R method is 50.21—85.14 kJ/mol and 5.14—7.24 kJ/mol at a heating rate range of 8—300 °C/min for the first and second pyrolysis stages, respectively. Aromatic hydrocarbons were dominant in the volatile products during fast pyrolysis of the coal, followed by the olefins, whereas the phenols were the third major components. With the increase of pyrolysis temperature, the heavy components in the volatile species increased; meanwhile the phenol cracking reactions were intensified. The carbon number of olefins was mainly concentrated in 3—9, and the aromatics were mainly composed of the compounds of C_6—C_(13).This study can provide a basic reference for fast pyrolysis of coal and other thermal chemical conversion processes.

关键词： fast pyrolysis bituminous coal kinetics volatiles

Behavior and Kinetics of Non-isothermal Pyrolysis of Coal at Different Heating Rates

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China Petroleum Processing & Petrochemical Technology 2017年第3期19卷 89-96页

作者： fan Junfeng Tian Bin An Xiaoxi Yin mengmeng Qiao Yingyun Tian Yuanyu Key Laboratory of Low Carbon Energy and Chemical Engineering Shandong University of Science and Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum

Investigations on the pyrolysis and kinetic behaviors during pyrolysis of fossil fuel samples, such as coal, are fundamental for developing the related technology and practical application. In this work, pyrolysis behavior and kinetics in the pyrolysis process of a coal sample were investigated by the thermogravimetric analyzer at a heating rate of 10, 40, 70,100, 200, and 500 °C/min, respectively. The pyrolysis process could be divided into four stages according to the TG/DTG curves. The first stage was mainly attributed to the removal of volatiles, and the second peak was the polycondensation reaction between the volatile components. It was found that more volatiles could be released from coal during pyrolysis at higher heating rate and the higher pyrolysis temperature was necessary for a rapid pyrolysis process. Kinetic analysis revealed that both the model-free(KAS and FWO) and the Coats-Redfern methods were suitable to describing the pyrolysis process, and the variation of activation energy(E) with the two types of kinetic models was consistent during the whole pyrolysis process. Furthermore, the heating rate did not alter the reaction sequence of the whole pyrolysis process, but higher heating rate could make the E value of the initial pyrolysis stage smaller.

关键词： pyrolysis behavior kinetic analysis TG/DTG curves activation energy

Efficient generation of targeted point mutations in the Brassica oleracea var.botrytis genome via a modified CRISPR/Cas9 system

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Horticultural Plant Journal 2022年第4期8卷 527-530页

作者： Guixiang Wang Mei Zong Di Liu Yage Wu Shouwei Tian Shuo Han Ning Guo mengmeng Duan Liming Miao fan Liu Beijing Vegetable Research Center Beijing Academy of Agriculture and Forestry SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops(North China)Ministry of AgricultureBeijing Key Laboratory of Vegetable Germplasm ImprovementBeijing 100097China

In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editing targets and hypocotyls of cauliflower were used as explants.For ALS gene,a C-to-T conversion in the Pro182 codon(CCT)can alter the encoded amino acid,likely resulting in herbicide resistance,and a C-to-T mutation in the Leu133 codon(CTT)in the CENH3 gene may produce a haploid inducer.Results indicated that the transformation efficiency was 1.8%–4.5%and the mutation efficiencies for the ALS and CENH3 genes were approximately 22%and 87%,respectively.The ALS mutant cauliflower showed strong herbicide resistance,with possible immediate implications for broadleaf weed control in cauliflower fields.

关键词： Cauliflower Targeted point mutations Base-editing CRISPR/Cas9 ALS CENH3

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未标定的视频小卫星深空目标凝视控制

国防科技大学学报 2022年第4期44卷 93-100页

作者：宋超范才智王猛猛国防科技大学空天科学学院湖南长沙410073

设计了一种目标凝视自适应姿态控制方法,可以实现未知目标位置和未标定相机参数条件下的目标凝视控制。根据运动学方程提取出恰当的未知参数,从而将参数进行线性化表示;引入关于未知参数的势函数,确保参数矩阵的秩满足稳定性要求;采用... 详细信息

设计了一种目标凝视自适应姿态控制方法,可以实现未知目标位置和未标定相机参数条件下的目标凝视控制。根据运动学方程提取出恰当的未知参数,从而将参数进行线性化表示;引入关于未知参数的势函数,确保参数矩阵的秩满足稳定性要求;采用了一个参数自更新律在线估计未知参数,提出了基于估计参数的自适应控制律。采用李雅普诺夫稳定性理论和芭芭拉特引理,证明了目标成像位置与期望成像位置的误差可以渐近收敛到零。仿真结果表明:目标位置未知且相机参数存在偏差的情况下,该自适应控制器能够有效地对深空目标进行凝视观测。

关键词：未标定相机视频小卫星姿态控制凝视控制自适应控制