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Reconstruction of biomimetic ionic channels within covalent organic frameworks for ultrafast and selective uranyl capture

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Science China Chemistry 2024年第10期67卷 3423-3431页

作者： cheng-Rong Zhang Xiao-Juan Chen cheng-peng niu cheng Meng Shun-Mo Yi Xin Liu Jia-Xin Qi Qiu-Xia Luo Ru-Ping Liang Jian-Ding Qiu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China College of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

The efficient extraction of uranium,as the primary component of nuclear energy,holds significant *** inspiration from the charge interaction observed in biological ion channels,we encapsulated negatively charged polystyrene sulfonate(PSS)or sodium polystyrene carboxylate(PVBA)into the nanochannels of amidoxime functionalized covalent organic framework(COF-AO)in-situ to alter the cavity environment of *** synthesized COF-AO-PSS and COF-AO-PVBA are used for ultra-fast and highly selective uranium *** negatively charged PSS/PVBA was confined in the COF-AO channel providing the driving force for uranium transport and blocking other ions,thus creating a highly selective“uranium highway”.Additionally,introducing sulfonate groups or carboxyl groups into COF-AO offers supplementary coordination environments and weak interactions with *** to charge-assisted migration and various interaction mechanisms,both COF-AO-PSS and COF-AO-PVBA exhibit faster adsorption kinetics and higher selectivity compared to COF-AO *** adsorption capacities are 3.8 times and 2.4 times that of COF-AO alone respectively which highlights the necessity for constructing biomimetic ion channels in uranium adsorption *** work presents a bionic adsorbent based on covalent organic frameworks(COFs)for the first time,overcoming environmental and equipment limitations associated with traditional photocatalysis and electrocatalysis methods for uranium capture,opening up new avenues for designing multifunctional materials that mimic biological systems.

关键词： covalent organic frameworks Uranium biomimetic ion-channels adsorption

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A Direct Method of Moving Planes to Fractional Power Sub Laplace Equations on the Heisenberg Group

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 364-379页

作者： Xin-jing WANG peng cheng niu School of Mathematics and Statistics Huanghuai UniversityZhumadianHenan 463000China Department of Applied Mathematics Northwestern Polytechnical UniversityXi'an 710129China

We give the direct method of moving planes for solutions to the conformally invariant fractional power sub Laplace equation on the Heisenberg *** method is based on four maximum principles derived *** symmetry and non... 详细信息

关键词： Heisenberg group fractional power sub Laplace equation the direct method of moving planes maximum principle

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Unique Continuation Properties Operators with for Generalized Baouendi-Grushin Singular Weights

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Acta Mathematica Sinica,English Series 2011年第8期27卷 1637-1644页

作者： Jia Lin WANG peng cheng niu ZDepartment of Applied Mathematics Northwestern Polytechnical University Xi'an 710072 P. R. China Key Laboratory of Numerical Simulation Technology of Jiangxi Province Gannan Normal University Ganzhou 341000 P. R. China

In this paper, properties of the spherical functions and Hardy-Sobolev inequalities of generalized Baouendi-Grushin vector fields are established, and then some unique continuation results for generalized Baouendi Gru... 详细信息

关键词： Unique continuation spherical function Hardy-Sobolev inequality generalized Baouendi -Grushin operator

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On First Order Interpolation Inequalities with Weights on the Heisenberg Group

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2493-2506页

作者： Ya Zhou HAN peng cheng niu Shu Tao ZHANG Department of Mathematics College of Science China diliang University Hangzhou 310018 P. R. China Department of Applied Mathematics Northwestern Polytechnical University Xi＇an 710072 P. R. China Department of Mathematics College of Science China Jiliang University Hangzhou 310018 P. R. China

In this paper, sufficient and necessary conditions for the first order interpolation inequalities with weights on the Heisenberg group are given. The necessity is discussed by polar coordinates changes of the Heisenberg group. Establishing a class of Hardy type inequalities via a new representation formula for functions and Hardy-Sobolev type inequalities by interpolation, we derive the sufficiency. Finally, sharp constants for Hardy type inequalities are determined.

关键词： Interpolation inequality Hardy-Sobolev type inequality Hardy type inequality Heisenberg group

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A novel 3D sp2 carbon-linked covalent organic framework as a platform for efficient electro-extraction of uranium

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Science China Chemistry 2023年第2期66卷 562-569页

作者： cheng-Rong Zhang Jia-Xin Qi Wei-Rong Cui Xiao-Juan Chen Xin Liu Shun-Mo Yi cheng-peng niu Ru-Ping Liang Jian-Ding Qiu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang330013China College of Chemistry Nanchang UniversityNanchang330031China

Extracting uranium from seawater offers opportunities for sustainable nuclear fuel supply,but the task is quite challenging due to the low uranium concentration(~3 ppb)in ***,based on the Knoevenagel condensation reaction of aldehyde and acetonitrile groups,a novel stable sp^(2)carbon-linked three-dimensional covalent organic framework(3D COF),TFPM-PDANAO was prepared as a porous platform for uranium extraction from *** TFPM-PDAN-AO designed with regular 3D pore channel of 7.12 A provides a specific channel for uranyl diffusion,which exhibits high selectivity and fast kinetics for uranium ***,the superior stability and optoelectronic properties enable it an excellent porous platform for uranium *** applying alternating voltages between-5 and 0 V,uranyl ions can rapidly migrate and enrich into the porous structure of TFPM-PDAN-AO,then inducing the electrodeposition of uranium compounds to form the charge neutral species(Na_(2)O(UO_(3)H_(2)O)x)with an unprecedentedly high adsorption capacity of 4,685 mg g^(-1).This work not only expands the application prospects of functionalized 3D COFs,but also provides a technical support for the electrodeposition adsorption of uranium from seawater.

关键词： three-dimension covalent organic framework uranium adsorption electrosorption

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Fabrication of Molecularly Imprinted Electrospun Nanofibers with Mono-amidoxime Functional Ligand for Efficient Decontamination of Toxic Organophosphates

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Chinese Journal of Polymer Science 2024年第4期42卷 446-456页

作者： Lan Wang peng Jiang Ya-Lin niu Jun-peng Cao Tian-Ying Guo Key Laboratory of Functional Polymer Materials Ministry of EducationInstitute of Polymer ChemistryCollege of Chemistry and Frontier Science Center for the Creation of New Organic SubstancesNankai UniversityTianjin300071China

There is an urgent imperative to discover practical and efficacious artificial catalysts for the expeditious decontamination of toxic organophosphates. Herein, we propose a novel molecularly imprinted approach utilizing electrospun fiber scaffolds. Specifically, an amidoxime-based functional polymer (PMAOX) has been synthesized, which contains amidoxime groups that can act as nucleophiles and ligands for the formation of catalytic active sites. This polymer was blended with polyacrylonitrile (PAN), a well-processable material, to prepare a nanofiber mat using electrospinning techniques. Then, the amidoxime side groups on fiber surface were further cross-linked after the molecular coordination of templates to complete the molecularly imprinting process. This approach can not only enhance the content of functional molecularly imprinted polymers without affecting structural stability, but also combines surface MI technology to fully expose and leverage the advantages of active sites. The as prepared molecularly imprinted electrospun nanofibers MIF-Zn-PMAOX/PAN-6/4 catalyzes the degradation of paraoxon with a half-life of 32 min, and MIF-Ag-PMAOX/PAN catalyzes the degradation of parathion with a half-life of 18 min. The maximum catalytic rate evidence rate enhancements nearly 3700-fold of the self-hydrolysis. Thus, the mono-amidoxime based molecularly imprinted fibers demonstrate the versatility and superiority as self-detoxifying for organophosphates.

关键词： Organophosphateshydrolysis Electrospinning Molecular imprinting

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Unsupervised construction of health indicator for rotating machinery via multi-criterion feature selection and attentive variational autoencoder

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Science China(Technological Sciences) 2024年第5期67卷 1524-1537页

作者： LI XinYu cheng ChangMing peng ZhiKe State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical Engineering Ningxia UniversityYinchuan750021China

Health indicator(HI)construction is a crucial task in degradation evaluation and facilitates the prognostic and health management(PHM)of rotating *** interference from artificial labeling,the HI construction approaches in an unsupervised manner have attracted substantial ***,current unsupervised methods generally struggle with two problems:(1)ignorance of both redundancy between features and global variability of features during the feature selection process;(2)inadequate utilization of information from different sampling *** tackle these problems,this work develops a novel unsupervised approach for HI construction that integrates multi-criterion feature selection and the Attentive Variational Autoencoder(Attentive VAE).Explicitly,a multi-criterion feature selection(Mc FS)algorithm together with an elaborately designed metric is proposed to determine a superior feature subset,considering the relevance,the redundancy,and the global variability of features ***,for the adequate utilization of the information from distinct sampling moments,a deep learning model named Attentive VAE is *** Attentive VAE is solely fed with the selected features in the health state for model training and the HI is derived through the reconstruction error to reveal the degradation degree of *** case studies based on genuine experimental datasets are involved to quantitatively evaluate the superiority of the developed approach,demonstrating its superiority over other unsupervised methods for characterizing degradation *** effectiveness of both the Mc FS algorithm and the Attentive VAE is verified by ablation experiments,respectively.

关键词： health indicator(HI) unsupervised learning multi-criterion feature selection global variability attention mechanism

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Blockchain-Based Key Management Scheme Using Rational Secret Sharing

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Computers, Materials & Continua 2024年第4期79卷 307-328页

作者： Xingfan Zhao Changgen peng Weijie Tan Kun niu State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang550025China Guizhou Big Data Academy Guizhou UniversityGuiyang550025China

Traditional blockchain key management schemes store private keys in the same location,which can easily lead to security issues such as a single point of ***,decentralized threshold key management schemes have become a research focus for blockchain private key *** security of private keys for blockchain user wallet is highly related to user identity authentication and digital asset *** threshold blockchain private key management schemes based on verifiable secret sharing have made some progress,but these schemes do not consider participants’self-interested behavior,and require trusted nodes to keep private key fragments,resulting in a narrow application scope and low deployment efficiency,which cannot meet the needs of personal wallet private key escrow and recovery in public *** design a private key management scheme based on rational secret sharing that considers the self-interest of participants in secret sharing protocols,and constrains the behavior of rational participants through reasonable mechanism design,making it more suitable in distributed scenarios such as the public *** proposed scheme achieves the escrow and recovery of personal wallet private keys without the participation of trusted nodes,and simulate its implementation on smart *** to other existing threshold wallet solutions and keymanagement schemes based on password-protected secret sharing(PPSS),the proposed scheme has a wide range of applications,verifiable private key recovery,low communication overhead,higher computational efficiency when users perform one-time multi-key escrow,no need for trusted nodes,and personal rational constraints and anti-collusion attack capabilities.

关键词： Blockchain smart contract rational secret sharing key management

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Effects of surface energy and substrate on modulus determination of biological films by conical indentation

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Science China(Technological Sciences) 2024年第6期67卷 1757-1764页

作者： DING Yue LI cheng-Ya niu XinRui WANG Gang-Feng Department of Engineering Mechanics SVLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

Micro-/nano-indentation has become prevalent in evaluating the mechanical characteristics of biological samples,such as cells and ***,the existing contact models describing conical indentation ignore the joint effects of surface energy and substrate,and consequently cannot accurately extract the Young's modulus of biological samples deposited on *** finite element methods,we examine the conical indentation of biological films on substrates while taking surface energy into *** on the dimensional analysis,the explicit relationship between load and indentation depth is achieved for films with their moduli varying from 0.001 to 100 times that of the *** the classical Sneddon's model was employed to analyze the load-depth data,the measured modulus could reach 18 times the real modulus for films on harder substrates,but only 4%of the real modulus for films on softer ***,in micro-/nano-indentations,neglecting the contribution of surface energy would result in an overestimation of the Young's modulus of films depending on the contact *** analytical expression provided here can be utilized to precisely deduce the mechanical characteristics of biological films deposited on substrate from the load and indentation depth data of a conical indentation.

关键词： biological film surface effect substrate effect indentation

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A unified pre-training and adaptation framework for combinatorial optimization on graphs

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Science China Mathematics 2024年第6期67卷 1439-1456页

作者： Ruibin Zeng Minglong Lei Lingfeng niu Lan cheng School of Computer Science and Technology University of Chinese Academy of SciencesBeijing100049China Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Economics and Management University of Chinese Academy of SciencesBeijing100190China School of Mathematics and Statistics Central South UniversityChangsha410075China

Combinatorial optimization(CO)on graphs is a classic topic that has been extensively studied across many scientific and industrial ***,solving CO problems on graphs through learning methods has attracted great *** deep learning methods,e.g.,graph neural networks(GNNs),have been used to effectively assist the process of solving ***,current frameworks based on GNNs are mainly designed for certain CO problems,thereby failing to consider their transferable and generalizable abilities among different COs on ***,simply using original graphs to model COs only captures the direct correlations among objects,which does not consider the mathematical logicality and properties of *** this paper,we propose a unified pre-training and adaptation framework for COs on graphs with the help of the maximum satisfiability(Max-SAT)*** first use Max-SAT to bridge different COs on graphs since they can be converted to Max-SAT problems represented by standard formulas and clauses with logical *** we further design a pre-training and domain adaptation framework to extract the transferable and generalizable features so that different COs can benefit from *** the pre-training stage,Max-SAT instances are generated to initialize the parameters of the *** the fine-tuning stage,instances from CO and Max-SAT problems are used for adaptation so that the transferable ability can be further *** experiments on several datasets show that features extracted by our framework exhibit superior transferability and Max-SAT can boost the ability to solve COs on graphs.

关键词： combinatorial optimization graph neural networks domain adaptation maximum satisfiability problem

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