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Integrated separation-electrochemical detection device based on wood column for online identification of enantiomer

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Nano Research 2024年第3期17卷 1893-1901页

作者： Junli Guo Yuanfei Xue Chenxi Zhao Junjian Zhao Zhida Gao Ye Mei Yan-Yan Song College of Sciences Northeastern UniversityShenyang 110004China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Chiral chemicals have attracted significant interest in the pharmaceutical industry,yet the separation methods to get pure enantiomers from racemic mixture are still challenging.To date,the separation of enantiomers still mainly depends on chromatography using high-cost chiral stationary phases.Herein,wood channels were used as the handheld integrated device,and enantiomer separation was simultaneously detected using an electrochemical detector.In this method,a chiral UIO-66(L-UIO-66)modified enantiomer separation zone and carbonized wood based online detection zone are integrated along a single wood column.Based on the in situ separation results from the chronoamperometry data,the wood device shows excellent separation ability for a wide range of electrochemically active enantiomers,including 3,4-dihydroxyphenylalanine,amino acids,ascorbic acid,carnitine,and penicillamine with high chirality purity.The unbiased molecular dynamic simulations indicate that the excellent chiral recognition and separation are attributed to the different barriers from the bound states to the dissociated state of the enantiomers in the homochiral microenvironment of the framework.This integrated enantiomer separation-electrochemical detection device provides a novel,easy,and low-cost platform for the separation of pure enantiomer from racemic mixture.

关键词： wood column integrated separation-detection device enantioselectivity online sensing free energy barrier

Pathways toward wearable and high-performance sensors based on hydrogels:toughening networks and conductive networks

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National Science Review 2023年第9期10卷 286-306页

作者： Junbo Zhu Jingchen Tao Wei yan Weixing song Beijing Key Laboratory for Optical Materials and Photonic Devices Department of Chemistry Capital Normal University

Wearable hydrogel sensors provide a user-friendly option for wearable electronics and align well with the existing manufacturing strategy for connecting and communicating with large numbers of Internet of Things devices.This is attributed to their components and structures,which exhibit exceptional adaptability,scalability,bio-compatibility,and self-healing properties,reminiscent of human skin.This review focuses on the recent research on principal structural elements of wearable hydrogels:toughening networks and conductive networks,highlighting the strategies for enhancing mechanical and electrical properties.Wearable hydrogel sensors are categorized for an extensive exploration of their composition,mechanism,and design approach.This review provides a comprehensive understanding of wearable hydrogels and offers guidance for the design of components and structures in order to develop high-performance wearable hydrogel sensors.

关键词： hydrogels electronic skin toughening networks conductive networks wearable sensors

Dynamic modeling and damage analysis of debris cloud fragments produced by hypervelocity impacts viaimage processing

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Frontiers of Information Technology & Electronic Engineering 2022年第4期23卷 555-570页

作者： Ru ZENG yan song Weizhen LV Department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghai200093China

It is always a challenging task to model the trajectory and make an efficient damage estimation of debris clouds produced by hypervelocity impact(HVI)on thin-plates due to the difficulty in obtaining high-quality fragment images from experiments.To improve the damage estimation accuracy of HVIs on a typical double-plate Whipple shield configuration,we investigate the distributive characteristic of debris clouds in successive shadowgraphs using image processing techniques and traditional numerical methods.The aim is to extract the target movement parameters of a debris cloud from the acquired shadowgraphs using image processing techniques and construct a trajectory model to estimate the damage with desirable performance.In HVI experiments,eight successive frames of fragment shadowgraphs are derived from a hypervelocity sequence laser shadowgraph imager,and four representative frames are selected to facilitate the subsequent feature analysis.Then,using image processing techniques,such as denoising and segmentation techniques,special fragment features are extracted from successive images.Based on the extracted information,image matching of debris is conducted and the trajectory of debris clouds is modeled according to the matched debris.A comparison of the results obtained using our method and traditional numerical methods shows that the method of obtaining hypervelocity impact experimental data through image processing will provide critical information for improving numerical simulations.Finally,an improved estimation of damage to the rear wall is presented based on the constructed model.The proposed model is validated by comparing the estimated damage to the actual damage to the rear wall.

关键词： Debris clouds Hypervelocity impact Image processing Damage estimation

The NAC transcription factor ONAC083 negatively regulates rice immunity against Magnaporthe oryzae by directly activating transcription of the RING-H2 gene OsRFPH2-6

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Journal of Integrative Plant Biology 2023年第3期65卷 854-875页

作者： yan Bi Hui Wang Xi Yuan Yuqing yan Dayong Li Fengming song National Key Laboratory for Rice Biology Institute of BiotechnologyZhejiang UniversityHangzhou 310058China College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China

NAC transcription factors(TFs) play critical roles in plant immunity by modulating the expression of downstream genes via binding to specific cis-elements in promoters. Here, we report the function and regulatory network of a pathogenand defense phytohormone-inducible NAC TF gene, ONAC083, in rice(Oryza sativa) immunity.ONAC083 localizes to the nucleus and exhibits transcriptional activation activity that depends on its C-terminal region. Knockout of ONAC083enhances rice immunity against Magnaporthe oryzae, strengthening pathogen-induced defense responses, and boosting chitin-induced pattern-triggered immunity(PTI), whereas ONAC083 overexpression has opposite effects. We identified ONAC083-binding sites in the promoters of 82genes, and showed that ONAC083 specifically binds to a conserved element with the core sequence ACGCAA. ONAC083 activated the transcription of the genes OsRFPH2-6, OsTrx1, and OsPUP4 by directly binding to the ACGCAA element. OsRFPH2-6, encoding a RING-H2 protein with an N-terminal transmembrane region and a C-terminal typical RING domain, negatively regulated rice immunity against M. oryzae and chitin-triggered PTI. These data demonstrate that ONAC083 negatively contributes to rice immunity against M. oryzae by directly activating the transcription of OsRFPH2-6 through the ACGCAA element in its promoter. Overall, our study provides new insight into the molecular regulatory network of NAC TFs in rice immunity.

关键词： ACGCAA element immunity Magnaporthe oryzae ONAC083 OsRFPH2-6 rice

Mechanistic insights into homogeneous electrocatalytic reaction for energy storage using finite element simulation

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Chinese Journal of Chemical Engineering 2022年第2期35卷 285-296页

作者： Peng song yan Li Shuang Yin Beijing Key Laboratory for Green Catalysis and Separation Department of Environmental and Chemical EngineeringBeijing University of TechnologyBeijing 100124China

The application of homogeneous electrocatalytic reactions in energy storage and conversion has driven surging interests of researchers in exploring the reaction mechanisms of molecular catalysts.In this paper,homogeneous electrocatalytic reaction between hydroxymethylferrocene(HMF)and L-cysteine is intensively investigated by cyclic voltammetry and square wave voltammetry for which,the secondorder rate constant(k_(ec))of the chemical reaction between HMF^(+)and L-cysteine is determined via a 1D homogeneous electrocatalytic reaction model based on finite element simulation.The corresponding k_(ec)(1.1(mol·m^(-3))^(-1)·s^(-1))is further verified by linear sweep voltammograms under the same model.Square wave voltammetry parameters including potential frequency(f),increment(Estep)and amplitude(ESW)have been comprehensively investigated in terms of the voltammetric waveform transition of homogeneous electrocatalytic reaction.Specifically,the effect of potential frequency and increment is in accordance with the potential scan rate in cyclic voltammetry and the increase of pulsed potential amplitude results in a conspicuous split oxidative peaks phenomenon.Moreover,the proposed methodology of k_(ec)prediction is examined by hydroxyethylferrocene(HEF)and L-cysteine.The present work facilitates the understanding of homogeneous electrocatalytic reaction for energy storage purpose,especially in terms of electrochemical kinetics extraction and flow battery design.

关键词： Homogeneous electrocatalytic reaction Electrochemical kinetics Square wave voltammetry Finite element modelling Energy storage

Uncertainty aversion and farmers' innovative seed adoption:Evidence from a field experiment in rural China

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Journal of Integrative Agriculture 2023年第6期22卷 1928-1944页

作者： WU Hai-xia song yan YU Le-shan GE yan Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Sino-Danish College University of Chinese Academy of SciencesBeijing 101408P.R.China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 100040P.R.China International Business School Shaanxi Normal UniversityXi’an 710100P.R.China School of Public Finance and Taxation Central University of Finance and EconomicsBeijing 100081P.R.China

Based on the microdata of 705 wheat farmers in the Loess Plateau, this study empirically analyzes the impact of uncertainty on farmers' adoption of innovative seeds using a field experiment. The results indicate that farmers are generally ambiguity-averse and risk-averse. In addition, farmers with higher ambiguity aversion and risk aversion are less likely to adopt innovative wheat seeds, where their risk aversion plays a dominant role. Enhancing information access will alleviate the negative influence of ambiguity aversion on farmers' adoption of innovative seeds, and interlinked insurance and credit contracts will be beneficial to ease the adverse effect of risk aversion on the adoption of innovative wheat seeds. Meanwhile, heterogeneity analysis reveals that the inhibitory effects of ambiguity aversion and risk aversion on innovative seed adoption are more significant among farmers with lower education and household income.The government can establish both ex-ante and ex-post relevant guarantee mechanisms to help farmers preferably cope with various uncertainties in the production process, remitting farmers' ambiguity aversion and risk aversion to enhance new agricultural technology adoption rates.

关键词： ambiguity aversion risk aversion technology adoption field experiment

Engineering large-scaled electrochromic semiconductor films as reproductive SERS substrates for operando investigation at the solid/liquid interfaces

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Chinese Chemical Letters 2022年第12期33卷 5169-5173页

作者： Lingling yang Jiuju Feng Jia-Ning Wang Zhida Gao Jingwen Xu Ye Mei Yan-Yan Song College of Sciences Northeastern UniversityShenyang 110004China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China NYU-ECNU Center for Computational Chemistry at NYU Shanghai Shanghai 200062China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China College of Chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China

Although surface-enhanced Raman spectroscopy(SERS)has been applied for gathering fingerprint information,even in single molecule analysis,the decayed Raman signals in aqueous solutions largely obstruct the on-site insight reaction process.In this study,large-scaled semiconductor films with multi-walled(TiO_(2)/WO_(3)/TiO_(2))nanopore distribution are fabricated by combining electrochemical anodization and sputtering technique,and then employed as the SERS substrates for detection of molecules at the solid/liquid interfaces.Given the remarkably improved electrochromic property of the multi-walled film,such SERS substrates were endowed with tunable oxygen vacancy(VO)density and distribution via simply applying electrochemical bias voltage,which enabled one to achieve an enhanced charge transfer efficiency and thus a remarkably increased Raman signal even in solution.The VO-rich SERS substrate is highly repeatable,thus providing a reliable platform for in-situ monitoring of the target molecules or intermediates at the solid/liquid interfaces.

关键词： Charge transfer Electrochromism Oxygen vacancies SERS substrate Solid liquid interface

Design,fabrication,and characterization of hierarchical mechanical metamaterials

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Frontiers of Mechanical Engineering 2024年第1期19卷 73-83页

作者： Jian song Junfei yan Bengang YI Automotive Engineering Research Institute BYD Auto Industry Co.Ltd.Shenzhen 518000China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

Natural mechanical materials,such as bamboo and bone,often exhibit superior specific mechanical properties due to their hierarchical porous architectures.Using the principle of hierarchy as inspiration can facilitate the development of hierarchical mechanical metamaterials(HMMs)across multiple length scales via 3D printing.In this work,we propose self-similar HMMs that combine octet-truss(OCT)architecture as the first and second orders,with cubic architecture as the third or more orders.These HMMs were fabricated using stereolithography 3D printing,with the length sizes ranging from approximately 200µm to the centimeter scale.The compressive stress–strain behaviors of HMMs exhibit a zigzag characteristic,and the toughness and energy absorption can be significantly enhanced by the hierarchical architecture.The compressive moduli are comparable to that of natural materials,and the strengths are superior to that of most polymer/metal foams,alumina hollow/carbon lattices,and other natural materials.Furthermore,the flexural stress–strain curves exhibit a nonlinear behavior,which can be attributed to the hierarchical architecture and local damage propagation.The relatively high mechanical properties can be attributed to the synergistic effect of the stretch-dominated OCT architecture and the bending-dominated cube architecture.Lastly,an ultralight HMM-integrated unmanned aerial vehicle(HMM-UAV)was successfully designed and printed.The HMM-UAV is~85%lighter than its bulk counterpart,remarkably extending the flight duration time(~53%).This work not only provides an effective design strategy for HMMs but also further expands the application benchmark of HMMs.

关键词： 3D printing mechanical metamaterials hierarchical architecture mechanical behavior unmanned aerial vehicle(UAV)

Topological Stability and Pseudo-orbit Tracing Property for Homeomorphisms on Uniform Spaces

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Acta Mathematica Sinica,English Series 2022年第2期38卷 431-442页

作者： Ke song yan Fan Ping ZENG School of Information and Statistics Guangxi University of Finance and EconomicsNanning 530003P.R.China

In this paper,we investigate the topological stability and pseudo-orbit tracing property for homeomorphisms on uniform spaces.We introduce the concept of topological stability for homeomorphisms on compact uniform spaces and prove that if a homeomorphism on a compact uniform space is expansive and has pseudo-orbit tracing property,then it is topologically stable.Moreover,we discuss the topological stability for homeomorphisms on uniform spaces from the view of localization.We introduce definitions of topologically stable point and shadowable point for homeomorphisms on uniform spaces and show that every shadowable point of an expansive homeomorphism on a compact uniform space is topologically stable.

关键词： Topological stability pseudo-orbit tracing property expansiveness uniform space