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Left Frobenius Pairs,Cotorsion Pairs and Weak Auslander-Buchweitz Contexts in Triangulated Categories

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Algebra Colloquium 2024年第2期31卷 285-308页

作者： Xin ma Tiwei Zhao Zhaoyong Huang nanqing Ding College of Science Henan University of EngineeringZhengzhou 451191China School of mathematical Sciences Qufu Normal University QufuShandong 273165China Department of mathematics Nanjing UniversityNanjing 210093China 不详

Let T be a triangulated category with a proper classξof *** introduce the notions of left Frobenius pairs,left(n-)cotorsion pairs and left(weak)Auslander-Buchweitz contexts with respect toξin *** show how to construct left cotorsion pais from left n-cotorsion pairs,and establish a one-to-one correspondence between left Frobenius pairs and left(weak)Auslander-Buchweitz *** applications are given in the Gorenstein homological theory of triangulated categories.

关键词： left Frobenius pairs left n-cotorsion pairs left(weak)Auslander-Buchweitz contexts homological dimensions

Design of new chemicals for advanced electrolytes

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Science China Chemistry 2024年第5期67卷 1378-1380页

作者： Haoran Cheng Zheng ma Qian Li Jun Ming State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei 230026China

This highlight is inspired by a recent article in nature Energy in which Liu and co-workers [1] from Tsinghua University designed a new asymmetric lithium salt (i.e., lithium 1,1,1-trifluoro-n-[2-[2-(2-methoxy ethoxy)ethoxy]ethyl] methanesulfonamide (Li FEA)) and applied it as a new lithium-salt additive in the conventional carbonate-based electrolyte,overcoming the incompatibility issue of carbonate electrolytes with lithium metal in lithium metal batteries (LMBs),even achieving a fast-charging feature.

关键词： lithium carbonate electrolyte

Lightweight Si_(3)n_(4)@SiO_(2) ceramic foam for thermal insulation and electromagnetic wave transparency

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nano Research 2024年第5期17卷 4298-4306页

作者： Zongwei Tong Xiangjie Yan Yuexiang Wang Kexun Li Weihai ma China-Blarus Belt and Road Joint Laboratory on Electromagnetic Environment Effect the 33rd Research Institute of ChinaElectronics Technology Group CorporationTaiyuan 030032China Key Laboratory for Advanced Ceramics and machining Technology of Ministry of Education School of Material Science and EngineeringTianjin UniversityTianjin 300072China Department of materials Science and Engineering Jinzhong UniversityJinzhong 030619China

Increasing porosity is one of the most direct ways to improve the thermal insulation and dielectric properties of *** now,many wet methods for preparing Si_(3)n_(4) ceramic foams usually face the problems of complex rheology,long period,and expensive cost,and the reported pore sizes of Si_(3)n_(4) ceramic foams are typically micron-grade,resulting in a lack of competitiveness in thermal insulation and wave-transparent *** this paper,the Si_(3)n_(4)@SiO_(2) ceramic foams were prepared using an efficient dry-method,which combined three processes of low temperature chemical vapor deposition(LTCVD),template,and isostatic *** method has the advantages of simple operation and short prepa.a.ion period,and can realize near-net size molding and mass *** addition,the evolution mechanisms of honeycomb microstructure and composition of Si_(3)n_(4)@SiO_(2) ceramic foam during sintering were studied by chemical reaction *** as-prepared Si_(3)n_(4)@SiO_(2) ceramic foam possesses low density(0.377 g·cm^(-3)),high compressive strength(7.5 MPa),low thermal conductivity(0.0808 W·m^(-1)·K^(-1)),and excellent dielectric properties(εnδn the frequency range of 8-18 GHz,and its maximum working temperature in air can reach up to 1100℃.It will be recommended to be applied in the interlayer of Si_(3)n_(4) ceramic radome to improve its thermal insulation and electromagnetic wave transparency performances.

关键词： silicon nitride ceramic foam honeycomb microstructure dielectric properties thermal insulation

Cha.a.terization of Arroyo Verde Epithermal Deposit:Pa.a.enesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo marcos Ma.a.ustina Cócola Mercedes Virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos mauro C.Geraldes Instituto Geologico del Sur(InGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad nacional de Rio negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the north Pa.a.onia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 ma(mineralization host rock)and 189.5±2.6 ma(overlying la.a..marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation cha.a.teristics,with gangue mineral textures associated with several ore *** probe microa.a.ysis determines electrum,silver minerals such as a.a.thite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena.a.d *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%naCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this da.a.we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular cha.a.ter has not been previously recorded for other sectors of the eastern north Pa.a.onian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

Intraseasonal variability of the Kuroshio observed via mooring at 18°n

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Journal of Oceanology and Limnology 2024年第2期42卷 468-483页

作者： Xin YUAn Qingye WAnG Jie ma Shijian HU Dunxin HU Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese a.a.emy of Sciences Beijing 100049China Laoshan Laboratory Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the *** measurements of the Kuroshio velocity were performed with an array of three profiler moorings(122.7°E,123°E,and 123.3°E)along 18°n from January 2018 to February *** ISV of the Kuroshio at 18°n was investigated based on a combination of mooring observations and global high-resolution HYbrid Coordinate Ocean Model rea.a.ysis *** estimated time-averaged transport in the upper 350 m across the observation transect was 6.5±2.6 Sv(1.0 Sv=10^(6)m^(3)/s).Two significant ISV peaks at 50-60 and~100 d were recognized in the power spectra of the meridional velocity and *** a.a.ysis indicated that the ISV at 50-60 d was caused by westward-propa.a.ing eddies at average propa.a.ion speed of~13 cm/s and wavelength of~635 *** ISV peak at~100 d was mainly caused by northward-propa.a.ing eddies generated in the north Equatorial Current *** investigation indicated that the ISV of the Kuroshio at 18°n is dominated by meridional transport,rather than by the zonal migration of the Kuroshio main *** findings provide a better understanding of the ISV of the Kuroshio east of Luzon Island.

关键词： intraseasonal variability(ISV) Kuroshio mooring observation eddy

Flexible interdigitated layered framework with multiple accessible active sites for high-performance CH_(3)I capture

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Science China Chemistry 2024年第5期67卷 1569-1577页

作者： Bo Tai Baoyu Li Linwei He Zhonglin ma Shujing Lin Mingxing Zhang Junchang Chen Fuqi Wu Long Chen Xing Dai Fuyin ma Zhifang Chai Shuao Wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China

The development of adsorbent materials for effective capture of radioactive iodomethane(CH_(3)I) from the off-gas of used nuclear fuel reprocessing, remains a significant and challenging line of research because currently state-of-art adsorbents still suffer from low binding affinity with CH_(3)I. Here, we proposed a brand-new adsorption topological structure by developing a 2D interdigitated layered framework, named SCU-20, featuring slide-like channel with multiple active sites for CH_(3)I capture. The responsive rotating-a.a.tive aperture of SCU-20 enables the optimal utilization of all active sites within the pore for highly selective recognition and capture of CH_(3)I. A record-breaking CH_(3)I uptake ca.a.ity of 1.84 g/g was achieved under static sorption conditions with saturated CH_(3)I vapor. Both experimental and theoretical findings demonstrated that the exceptional uptake of SCU-20 towards CH_(3)I can be attributed to the confined physical electrostatic adsorption of F sites, coupled with the chemical nitrogen methylation reaction with uncoordinated n atoms of pyrazine. Moreover, dynamic CH_(3)I uptake ca.a.ity potentially allows for the capture of CH_(3)I in simulated real-world off gas reprocessing conditions. This study highlights the potential of SCU-20 as a promising candidate for efficient capture of iodine species and contributes to the development of effective solutions for radioactive iodine remediation.

关键词： 2D interdigitated layered framework iodomethane dual-sites electrostatic interaction physisorption and chemisorption

Open-vessel Synthesis of Poly-n-methoxyethylglycine

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Chemical Research in Chinese Universities 2024年第1期40卷 153-158页

作者： LIU Guojan ma Ke CHEn Qi ZHAnG Donghui LIU Runhui State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai200237P.R.China Key Laboratory for Ultrafine materials of Ministry of Education Frontiers Science Center for Materiobiology and Dynamic ChemistryShanghai Frontiers Science Center of Optogenetic Techniques for Cell MetabolismResearch Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237P.R.China School of Biotechnology East China University of Science and TechnologyShanghai200237P.R.China

Polypeptoids are widely used in biological applications owing to their diverse functions and proteolytic *** type of polypeptoids,poly-n-methoxyethylglycine(P-nmeg),has been found to possess remarkable hydrophilicity and notable properties in terms of protein,cell,and bacterial ***,the currently known synthesis methods of P-nmeg include solid-phase synthesis,which is time-consuming and difficult to scale up,and n-substituted n-carboxyanhydride(nnCA)ring-opening polymerization,whose monomers were difficult to *** this study,we used the chemical stable nmeg n-phenoxycarbonyl(nPC)as the monomer,which was obtained without the use of highly toxic reactants,such as phosgene or phosphorus halide,to synthesize P-nmeg under open-vessel *** adding BnnH_(2) as an initiator at 80℃,we can obtain controllable short chain length P-nmeg with narrow dispersity.

关键词： Open-vessel Polypeptoid synthesis Poly-n-methoxyethylglycine Stable monomer narrow dispersity

Insulation Design Rule for a Spacer in SF_(6)/n_(2)-filled DC Gas Insulated Appa.a.us

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 727-735页

作者： Hongyang Zhou Guoming ma Meng Zhang Cong Wang Youping Tu Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China

A recurring challenge of a DC SF_(6)/n_(2)-filled GIS/GIL appa.a.us is the charge accumulation at DC *** conventional design rules and knowledge of AC spacers may not be applicable for this new type of appa.a.us.A novel design rule is proposed considering the effect of accumulated charge on the threshold of electric field strength being resistant to the superposed voltage.A surface charge accumulation simulation model is introduced,and the key pa.a.eters in the simulation model are *** addition,an experimental platform for a 100 kV spacer flashover test is *** flashover tests under superimposed voltage with opposing polarities are carried out,and the withstanding voltage of the spacer is ***,based on the proposed model,the threshold of the surface electric field strength(tangential component)on the DC spacer in SF_(6)/n_(2) mixed gases is *** a reliable insulation design of a DC GIS/GIL appa.a.us filled with 0.7 MPa SF_(6)/n_(2),the threshold of surface electric field strength on the DC spacer is 12 kV/*** insulation design rule can be referenced in the design of a high-voltage DC SF_(6)/n_(2)-filled GIS/GIL appa.a.us.

关键词： Charge accumulation DC spacer flashover voltage SF_(6)/n_(2) threshold of surface electric field strength

Universal insertion of molecules in ionic compounds under pressure

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national Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming ma Chris J.Pickard Hanyu Liu maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard materials & Key Laboratory of material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of materials Science & Metallurgy University of Cambridge Advanced Institute for materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, n2, CO2, nH3, H2O and CH4may react with naC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding na.a.d Cl ions. In contrast, the most stable molecule among all examples, n2, is found to transform into cyclo-n5-anions while reacting with naC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior