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Metal-Backboned Polymer:Conception,Design and Synthesis

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Chinese Journal of Polymer Science 2023年第1期41卷 3-6页

作者： kai-Wen zeng Hui-Sheng Peng State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science Fudan UniversityShanghai200438China

The backbones of polymers are generally composed of non-metal elements such as C,N,O and Si.Here we propose and synthesize a new class of polymers whose backbones are completely made from metal atoms connected by chemical bonds,and they are thus named metal-backboned polymers.As a demonstration,nickel is selected as the metal to construct the nickel-backboned polymers with varied lengths,which are verified by mass spectrometry and studied by ultraviolet-visible spectroscopy.These metal-bonded polymers open up a new avenue to develop functional polymers in the future.

关键词： Metal-backboned Nickel Functional Polymer

Bubble model analysis on the cell formation of a green alga

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International Journal of Biomathematics 2020年第5期13卷 21-31页

作者： Yuandi Wang Nanjun Yan Zhigang Zhou Kai Zeng Department of Mathematics Shanghai University Shanghai 200444 P.R.China College of A qua-life Sciences and Technology Shanghai Ocean University Shanghai 201306 P.R.China

Mathematical simulation for cell and division,a complex process resulting from a series of major morphological evolution and biological mechanisms,is shown by using variational principle.Groups of differential equation systems with boundary conditions for the cell walls satisfying come out from analysis on minimally total length.Double bubble model for cell geometric formation is found and a mechanism for tri-bubble model is also investigated here.An interesting fact is that every angle between any two tangent lines at the same intersections of cell edges for both double bubble and tri-bubble is equal to 27r/3.In addition to the derivation of these differential equation models,these theories are also applied to the specific experimental data analysis,and it is found that the model is very consistent with the experimental results.

关键词： Green algae cell mathematical model bubble differential equation variational principle

Role of Stokes Drift in Ocean Dynamics Under Typhoon Conditions in the Bohai Sea

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Journal of Ocean University of China 2024年第1期23卷 33-45页

作者： LI Haoqian WAN kai WANG Menghan DENG zeng’an CAO Yu North China Sea Marine Forecasting Center Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation Qingdao 266061China North China Sea Offshore Engineering Survey Institute Qingdao 266061China School of Marine Science and Technology Tianjin UniversityTianjin 300072China South China Sea Marine Forecasting Center Guangzhou 510006China

The effect of Stokes drift production(SDP),which includes Coriolis-Stokes forcing,Langmuir circulation,and Craik-Lei-bovich vortexes,on the upper ocean during typhoon passage in the Bohai Sea(BS),China,is investigated by using a coupled wave-current model.The role of SDP in turbulent mixing and the further dynamics during the entire typhoon period are comprehensively stud-ied.Experimental results show that SDP greatly increases turbulent mixing at all depths under typhoon conditions by up to seven times that under normal weather conditions.SDP generally strengthens sea surface cooling by more than 0.4℃,with the maximum reduction in sea surface temperature(SST)at the during-typhoon stage exceeding 2℃,which is approximately seven times larger than that under normal weather conditions.The SDP-induced decrease in current speed can exceed 0.2ms^(-1),and the change in current direction is generally opposite the wind direction.These results suggest that Stokes drift depresses the effect of strong winds on currents by intensifying turbulent mixing.Mixed layer depth(MLD)is distinctly increased by O(1)during typhoons due to SDP and can deepen by more than 5m.In addition,the continuous effects of SDP on SST,current,and MLD at the after-typhoon stage indi-cate a hysteretic response between SDP and typhoon actions.

关键词： Stokes drift production Langmuir turbulence rurbulent mixing typhoon coupled model

Mechanically Strong Proteinaceous Fibers:Engineered Fabrication by Microfluidics

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Engineering 2021年第5期7卷 615-623页

作者： Jing Sun Jingsi Chen kai Liu Hongbo zeng Institute of Organic Chemistry University of UlmUlm 89081Germany Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada Department of Chemistry Tsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Lightweight and mechanically strong natural silk fibers have been extensively investigated over the past decades.Inspired by this research,many artificial spinning techniques(wet spinning,dry spinning,electrospinning,etc.)have been developed to fabricate robust protein fibers.As the traditional spinning methods provide poor control over the as-spun fibers,microfluidics has been integrated with these techniques to allow the fabrication of biological fibers in a well-designed manner,with simplicity and cost efficiency.The mechanical behavior of the developed fibers can be precisely modulated by controlling the type iop and size of microfluidic channel,flow rate,and shear force.This technique has been successfully used to manufacture a broad range of protein fibers,and can accelerate the production and application of protein fibers in various fields.This review outlines recent progress in the design and fabrication of protein-based fibers based on microfluidics.We first briefly discuss the natural spider silk-spinning process and the microfluidics spinning process.Next,the fabrication and mechanical properties of regenerated protein fibers via microfluidics are discussed,followed by a discussion of recombinant protein fibers.Other sourced protein fibers are also reviewed in detail.Finally,a brief outlook on the development of microfluidic technology for producing protein fibers is presented.

关键词： Proteinaceous fibers Microfluidics Soft material Biomaterials

Extraction and analysis of tree canopy height information in high-voltage transmission-line corridors by using integrated optical remote sensing and LiDAR

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Geodesy and Geodynamics 2023年第3期14卷 292-303页

作者： Jinpeng Hao Xiuguang Li Hong Wu kai Yang Yumeng zeng Yu Wang Yuanjin Pan State Grid Ningxia Electric Power Research Institute Yinchuan 750011China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430061China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Hubei LuoJia Laboratory Wuhan UniversityWuhan 430079China

Traditional inspection methods cannot quickly and accurately monitor tree barriers and safeguard the transmission lines.To solve these problems,in this study,we proposed a rapid canopy height information extraction method using optical remote sensing and LiDAR,and used UAV optical imagery with LiDAR to monitor the height of trees in a university and a high-voltage transmission line corridor in the Ningxia region.The results showed that the relative error of tree height extraction using UAV optical images was less than 5%,and the lowest relative error was 0.11%.The determination coefficient R^(2) between the optical image tree height extraction results and the measured tree height was 0.97,thus indicating a high correlation for both.In the field of tree barrier monitoring,the determination coefficient R^(2) of tree height extracted using airborne LiDAR point cloud,and canopy height model(CHM)and of the measured tree height were 0.947 and 0.931,respectively.The maximum and minimum relative error in tree height extraction performed using point cloud was 2.91%and 0.2%,respectively,with an extraction accuracy of over 95%.The experimental results demonstrated that it is feasible to use UAV optical remote sensing and LiDAR in monitoring tree barriers and tree height information extraction quickly and accurately,which is of great significance for the risk assessment and early warning of tree barriers in transmission-line corridors.

关键词： UAV LiDAR Power line Tree height

新质生产力:复合概念、发展基础与系统创新路径

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深圳大学学报（人文社会科学版） 2024年第2期41卷 5-15页

作者：曾宪聚曾凯深圳大学管理学院/深圳大学新质生产力研究院广东深圳518060 中国人民大学商学院北京100872

作为一个包含政治概念、学术概念与产业概念“三位一体”的复合概念,新质生产力是全球政治意识形态变化和大变局加速演进下国家竞争力的核心标志,是以科技创新驱动生产要素升级和生产关系变革的根本动力,是培育和形成战略性新兴产业、... 详细信息

作为一个包含政治概念、学术概念与产业概念“三位一体”的复合概念,新质生产力是全球政治意识形态变化和大变局加速演进下国家竞争力的核心标志,是以科技创新驱动生产要素升级和生产关系变革的根本动力,是培育和形成战略性新兴产业、未来产业的逻辑起点和落脚点。创新在发展新质生产力中起主导作用。我国有创新载体、创新要素和创新市场优势:创新主体多元,工业体系完备,人才梯队健全,数字经济发达,数字基础设施较为完善,市场规模超大,创新牵引能力突出。遵循“孕育-生成-发展-扩散-持续”这一动态演进逻辑,强化颠覆性和渐进性科技创新双元平衡;优化组织管理模式,培育新质生产关系;厘清产业发展规律,促进产业融合升级;构建“产业-区域-数智”融通创新生态系统,优化制度创新路径,推进多重国家战略创新联动,即从科技创新、组织创新、产业创新、生态创新到制度创新,是新质生产力系统性创新路径。

关键词：新质生产力新质生产关系高质量发展复合概念科技创新系统创新路径

Effect of Na(Ⅰ)-H2O clusters on self-assembly of sandwich-type U(Ⅵ)-containing silicotungstates and the efficient catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles

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Tungsten 2022年第2期4卷 149-157页

作者： Ke Li Xiao-Ling Lin Kai Zeng Xiao-Fei Gao Wei Cen Yu-Feng Liu Guo-Ping Yang Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation Jiangxi Province Key Laboratory of Synthetic ChemistryEast China University of TechnologyNanchang330013China Russia School of Social and Human Sciences-International Relations Tyumen State UniversityTyumen625003Russia

In this study,a sandwich-type uranium(Ⅵ)-containing silicotungstate KNa11H2(H2O)30[Na(UO2)(SiW9O34)]2·8H2O(1)with new three-dimensional(3D)structure was synthesized and characterized using single-crystal X-ray diffraction,Fourier transform infrared,Raman,solid-state ultraviolet–visible diffuse reflection spectra,thermogravimetric analysis and powder X-ray diffraction.Single crystal analysis revealed that the Na(I)-H2O clusters in 1 showed a two-dimensional structure similar to(4,4)-network and resulted in the formation of a new 3D structure of 1.In addition,it was notable that 1 presented excellent catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles via the cyclization reaction of 1,3-diketones with various substituted benzenesulfonyl hydrazides.

关键词： Uranium Polyoxotungstates Condensation reaction Phenylsulfonyl-1H-pyrazoles

Polypropylene crisper and 1-MCP delay the softening,lignification and transcription levels of related enzyme genes of golden needle mushrooms(Flammulina velutipes)

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Journal of Integrative Agriculture 2022年第1期21卷 249-260页

作者： WANG Wen-jun LI Yao LI Fu-hua zeng kai-fang MING Jian College of Food Science Southwest UniversityChongqing 400715P.R.China Research Center of Food Storage&Logistics Southwest UniversityChongqing 400715P.R.China

The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.Treatments with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

关键词： Flammulina velutipes polypropylene crisper 1-MCP softening and lignification transcription levels

Surfactant-assisted removal of 2,4-dichlorophenol from soil by zero-valent Fe/Cu activated persulfate

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Chinese Journal of Chemical Engineering 2022年第4期35卷 447-455页

作者： Ling Xu Ji Li Wenbin zeng kai Liu Yibing Ma Liping Fang Chenlu Shi Faculty of Material Science and Chemistry China University of GeosciencesWuhan 430074China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management Institute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangzhou 510650China Macao Environmental Research Institute Macao University of Science and TechnologyTaipaMacaoChina

The organic compounds contaminated soil substantially threatens the growth of plants and food safety.In this study,we synthesis zero-valent bimetallic Fe/Cu catalysts for the degradation of 2,4-dichlorophenol(DCP)in soils with persulfate(PS)in combination of organic surfactants and exploring the main environmental impact factors.The kinetic experiments show that the 5%(mass)dosage of Fe/Cu exhibits a higher degradation efficiency(86%)of DCP in soils,and the degradation efficiency of DCP increases with the increase of the initial PS concentration.Acidic conditions are favorable for the DCP degradation in soils.More importantly,the addition of Tween-80,and Triton-100 can obviously desorb DCP from the soil surface,which enhances the degradation efficiency of DCP in soils by Fe/Cu and PS reaction system.Furthermore,the Quenching experiments demonstrate that SO_(4)^(-1)·and·OH are the predominant radicals for the degradation of DCP during the Fe/Cu and PS reaction system as well as non-radical also exist.The findings of this work provide an effective method for remediating DCP from soils.

关键词： Zero-valent iron and copper Advanced oxidation process Persulfate Chlorinated organic pollutants Surfactant