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重金属污染土壤与地下水修复工程环境监测

世界有色金属 2024年第15期 121-123页

作者：余蕊蕊甘肃省有色地质调查院

随着“绿色发展”理念的提出，环境保护日益成为人们关注的焦点。我国进入21世纪后，工业化进程不断加快，但在高速发展过程中，土壤、地下水中的重金属污染，与“绿色发展”理念相悖。在这种情况下，国家需要尽快开展水土保持项目建设... 详细信息

随着“绿色发展”理念的提出，环境保护日益成为人们关注的焦点。我国进入21世纪后，工业化进程不断加快，但在高速发展过程中，土壤、地下水中的重金属污染，与“绿色发展”理念相悖。在这种情况下，国家需要尽快开展水土保持项目建设。要确保整治工作的顺利开展，必须建立健全的环境监控系统，并选择合适的监控方法。针对这一问题，本文以我国典型土壤与地下水为研究对象，研究不同区域重金属污染的防治策略，以期为环境保护与管理提供理论基础与技术支持。

关键词：重金属污染土壤地下水环境监测

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： rui-rui Liu Li-Bo Mao Shu-Hong yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li rui-rui Zhang Ke-Xin Li Shuang Wei yu-Mei Liu rui-Xia Liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

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Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： rui-rui Liu Qian-Qian Shi yu-Feng Meng Yong Zhou Li-Bo Mao Shu-Hong yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Is Yang-Mills theory unitary in fractional spacetime dimensions?

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 59-64页

作者： Qingjun Jin Ke Ren Gang Yang rui yu Graduate School of China Academy of Engineering Physics Beijing 100193China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Hangzhou 310024China School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Beijing Computational Science Research Center Beijing 100193China

We present concrete evidence that Yang-Mills theory exhibits non-unitarity in non-integer spacetime *** violation of unitarity stems from evanescent operators that,while vanishing in four dimensions,are non-zero in general d *** demonstrate that these evanescent operators lead to the emergence of both negative-norm states and complex anomalous dimensions.

关键词： gauge field theories field theories in dimensions other than four renormalization

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Study on the coupling calculation method for the launch dynamics of a self-propelled artillery multibody system considering engraving process

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DEFENCE TECHNOLOGY 2024年第9期39卷 67-85页

作者： Zhang, Shujun rui, Xiaoting yu, Hailong Dong, Xiaoli Nanjing Univ Sci & technol Inst Launch Dynam Nanjing 210094 Peoples R China Natl Key Lab Complex Multibody Syst Dynam Nanjing 210094 Peoples R China

The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics, capable of addressing the challenges of complex modeling, diminished computational efficiency, and imprecise analyses of system dynamic responses found in the dynamics research of intricate multi-rigid-flexible body systems, such as self-propelled artillery. This advancement aims to enhance the firing accuracy and launch safety of self-propelled artillery. Recognizing the shortfall of overlooking the band engraving process in existing theories, this study introduces a novel coupling calculation methodology for the launch dynamics of a self-propelled artillery multibody system. This method leverages the ABAQUS subroutine interface VUAMP to compute the dynamic response of the projectile and barrel during the launch process of large-caliber self-propelled artillery. Additionally, it examines the changes in projectile resistance and band deformation in relation to projectile motion throughout the band engraving process. Comparative analysis of the computational outcomes with experimental data evidences that the proposed method offers a more precise depiction of the launch process of self-propelled artillery, thereby enhancing the accuracy of launch dynamics calculations for self-propelled artillery. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Self-propelled artillery Engraving process Multibody system dynamics Launch dynamics TRANSFER-MATRIX METHOD PROJECTILE 155 MM SIMULATION

Dual-salt poly(tetrahydrofuran) electrolyte enables quasi-solid-state lithium metal batteries to operate at -30 ℃

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Journal of Energy Chemistry 2024年第9期96卷 456-463页

作者： Zhiyong Li Zhuo Li rui yu Xin Guo School of Materials Science and Engineering State Key Laboratory of Material Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074HubeiChina The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)***,we prepare a dual-salt poly(tetrahydrofuran)-based electrolyte consisting of lithium hexafluorophosphate and lithium difluoro(oxalato)borate(LiDFOB).The Li-salt anions(DFOB−)not only accelerate the ring-opening polymerization of tetrahydrofuran,but also promote the formation of highly ion-conductive and sustainable interphases on Li metal anodes without sacrificing the Li^(+)conductivity of electrolytes,which is favorable for Li^(+)transport kinetics at low *** of this polymer electrolyte in Li||LiFePO_(4)cells show 82.3%capacity retention over 1000 cycles at 30℃and endow stable discharge capacity at−30℃.Remarkably,the Li||LiFePO4 cells retain 52%of their room-temperature capacity at−20℃and 0.1 *** rational design of dual-salt polymer-based electrolytes may provide a new perspective for the stable operation of quasi-solid-state batteries at low temperatures.

关键词： Poly(tetrahydrofuran) Dual-salt electrolyte Solidel ectrolyte interphase Low-temperature operation Quasi-solid-state battery

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Understanding Bonding Nature of α-Keggin Polyoxometalates [XW12O40]n- (X = Al, Si, P, S): A Generalized Superatomic Perspective

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 176-183页

作者： Li, rui Shi, yulei yu, Famin Wang, rui Yan, Haitao Teo, Boon K. Wang, Zhigang Capital Normal Univ Dept Phys Beijing 100048 Peoples R China Jilin Univ Coll Phys Key Lab Mat Simulat Methods & Software Minist Educ Changchun 130012 Peoples R China Jilin Univ Inst Atom & Mol Phys Changchun 130012 Peoples R China Jilin Univ Inst Theoret Chem Coll Chem Changchun 130012 Peoples R China Xiamen Univ Coll Chem & Chem Engn State Key Lab Phys Chem Solid Surfaces Xiamen 361005 Peoples R China

alpha-Keggin polyoxometalates (POMs) [XW12O40](n-) (X = Al, Si, P, S) are widely used in batteries owing to their remarkable redox activity. However, the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding nature. Here, first-principles calculations show that XW12 are core-shell structures composed of a shell and an XO4n- core, both are stabilized by covalent interactions. Interestingly, owing to the presence of a substantial number of electrons in W12O36 shell, the frontier molecular orbitals of XW12 are not only strongly delocalized but also exhibit superatomic properties with high-angular momentum electrons that do not conform to the Jellium model. Detailed analysis indicates that energetically high lying filled molecular orbitals (MOs) have reached unusually high-angular momentum characterized by quantum number K or higher, allowing for the accommodation of numerous electrons. This attribute confers strong electron acceptor ability and redox activity to XW12. Moreover, electrons added to XW12 still occupy the K orbitals and will not cause rearrangement of the MOs, thereby maintaining the stability of these structures. Our findings highlight the structure-activity relationship and provide a direction for tailor-made POMs with specific properties at atomic level.

关键词： first principles molecular orbital polyoxometalate redox activity superatom ELECTRONIC SHELL STRUCTURE CORRELATION-ENERGY BASIS-SET DENSITY STABILITY CHEMISTRY HETEROPOLYANIONS ORBITALS MODEL DFT

A novel polyionic liquid with lubricity and viscosity-increasing dual functionalities as the additive in aqueous lubrication system

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Friction 2024年第4期12卷 698-710页

作者： Bo yu Kun ZOU rui WANG Qiang CHEN rui DONG Xiao LIU Jiaying ZHANG Wenquan LV Qiangliang yu Meirong CAI Feng ZHOU College of Science Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 264006China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Yantai 264006China Institute of Polymer Materials Nanjing Forestry UniversityNanjing 210037China

The polyionic liquid poly-PEGMA-r-METAC(PPM)with quaternary ammonium has been synthesized and evaluated as additive in aqueous lubricating *** rheological behavior of aqueous lubricating fluids with PPM has been characterized to confirm PPM’s function as a viscosity *** tribological behavior of aqueous lubricating fluids with PPM has been investigated on SRV-V and MTM testing *** was found that PPM has excellent viscosity-increasing,lubricating,and anti-wear properties as an additive for aqueous,which can be attributed to the ability of PPM to form the protective film and boundary tribofilm generated from complex tribochemical reaction on rubbing *** obtained PPM with dual functions of anti-corrosion additives and viscosity index improver can play an important role in diverse lubrication regimes.

关键词： polyionic liquid lubricant additives viscosity modifier lubrication regime