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Electrochemical conversion of organic compounds and inorganic small molecules

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Science China Chemistry 2024年第10期67卷 3223-3246页

作者： Weimei zeng Youai Qiu Department of Chemistry Nankai UniversityTianjin 300071China

Electrochemical synthesis presents a facile and sustainable strategy to produce valuable *** review summarizes the most recent advances in electrosynthesizing value-added compounds with inorganic small ***“small molecules”refers to a broad spectrum of chemicals,we mainly focus on the electrochemical conversion of CO_(2),h_(2)O/D_(2)O,Nh_(3)and SO_(2)until March *** review intends to compare the results and display general trends throughout the field,with an emphasis on the substrate scope and mechanical ***,we propose several techniques and protocols that can enable a more fundamental understanding of the electrochemical reaction involving inorganic small molecules and help drive this methodology toward commercialization.

关键词： electrochemical synthesis inorganic small molecule organic synthesis carbon dioxide water

Structural integration of solar desalination system

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Science China Materials 2024年第6期67卷 2039-2041页

作者： Diling Yang hao Zhang h.ngbo zeng School of Materials and Environmental Engineering Hunan University of HumanitiesScience and TechnologyLoudi 417000China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada

As population grow and climate change place significant water stress on numerous regions,the demand for efficient and environmentally friendly water resource solutions becomes increasingly *** address this challenge,desalination technology has received much attention and is widely employed,with a recent emphasis on solar-powered solutions driven by the global push for carbon neutrality.

关键词： neutral system integration

Achieving structurally stable O3-type layered oxide cathodes through site-specific cation-anion co-substitution for sodium-ion batteries

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Journal of Energy Chemistry 2024年第6期93卷 411-418,I0011页

作者： Yihao Shen Chen Cheng Xiao Xia Lei Wang Xi Zhou Pan zeng Jianrong zeng Liang Zhang Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123JiangsuChina Institute for Advanced Study School of Mechanical EngineeringChengdu UniversityChengdu 610106SichuanChina Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123JiangsuChina

O3-type layered oxides have garnered great attention as cathode materials for sodium-ion batteries because of their abundant reserves and high theoretical ***,challenges persist in the form of uncontrollable phase transitions and intricate Na^(+)diffusion pathways during cycling,resulting in compromised structural stability and reduced capacity over *** study introduces a special approach employing site-specific Ca/F co-substitution within the layered structure of O_(3)-NaNi_(0.5)Mn_(0.5)O_(2) to effectively address these ***,the strategically site-specific doping of Ca into Na sites and F into O sites not only expands the Na^(+)diffusion pathways but also orchestrates a mild phase transition by suppressing the Na^(+)/vacancy ordering and providing strong metal-oxygen bonding strength,*** as-synthesized Na_(0.95)Ca_(0.05)Ni_(0.5)Mn_(0.5)O_(1.95)F_(0.05)(NNMO-CaF)exhibits a mild O3→O3+O'3→P3 phase transition with minimized interlayer distance variation,leading to enhanced structural integrity and stability over extended *** a result,NNMO-CaF delivers a high specific capacity of 119.5 mA h g^(-1)at a current density of 120 mA g^(-1)with a capacity retention of 87.1%after 100 *** study presents a promising strategy to mitigate the challenges posed by multiple phase transitions and augment Na^(+)diffusion kinetics,thus paving the way for high-performance layered cathode materials in sodium-ion batteries.

关键词： Sodium-ion batteries O3-type layered oxides Site-specific co-doping Phase transition

Origin of the near-room temperature resistance transition in lutetium with h2/N2 gas mixture under high pressure

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National Science Review 2024年第7期11卷 26-32页

作者： Di Peng Qiaoshi zeng Fujun Lan Zhenfang Xing Zhidan zeng Xiaoxing Ke Yang Ding ho-kwang Mao Key Laboratory of Materials Physics Institute of Solid State Physics Hefei Institutes of Physical Science(HFIPS)Chinese Academy of Sciences Science Island Branch Graduate School of University of Science and Technology of China Center for high Pressure Science and Technology Advanced Research Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS) State Key Laboratory of Superhard Materials Institute of PhysicsJilin University College of Materials Science&Engineering Beijing University of Technology

The recent report of room-temperature superconductivity at near-ambient pressure in nitrogen-doped lutetium hydride（Lu-h-N） by Dasenbrock-Gammon et al. [Nature 615, 244–250（2023）] has attracted tremendous attention due to its anticipated great impact on technology. however, the results could not be independently reproduced by other groups worldwide in follow-up studies, which elicited intense controversy. here, we develop a reliable experimental protocol to minimize the extensively concerned extrinsic influences on the sample by starting the reaction from pure lutetium loaded with an h2/N2gas mixture in a diamond anvil cell under different pressures and temperatures and simultaneously monitoring the entire chemical reaction process using in situ four-probe resistance measurements. Therefore, we could repeatedly reproduce the near-room temperature upsurge of electrical resistance at a relatively early stage of the chemical reaction. however, the mechanism is suggested to be a metal-to-semiconductor/insulator transition associated with the structural modulation in the non-stoichiometric Lu-h-N, rather than superconductivity.

关键词： superconductivity high pressure lutetium hydride resistance transition metal-to-semiconductor/insulator transition

Stable graphene oxide-based lyotropic liquid crystals for interfacial lubrication

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Friction 2024年第5期12卷 954-967页

作者： Yumei GUO hanglin LI Jiusheng LI Xiangqiong zeng Laboratory for Advanced Lubricating Materials Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China

Lyotropic liquid crystals have lubricating properties due to their ordered assembly and fluidity,whose mesogens are often characterized by amphiphilic *** the attention that graphene oxide(GO)has been studied as a novel amphiphilic lyotropic mesogen this decade,and GO applied as a lubrication additive has been demonstrated in both oil and water-based systems,little research reveals the interfacial lubrication of GO liquid crystals *** work reports that GO aqueous dispersion can form lyotropic liquid crystals above a specific critical concentration of 5.00 mg/mL,providing a form of stable water-based lubricant,which can keep stable for several months and can reduce friction by 37.3%and wear by 25.24%.The liquid crystal phase was verified by polarizing microscope and synchrotron radiation small-angle X-ray scattering,and its rheological properties and viscoelasticity were studied by interfacial *** formation of lyotropic liquid crystals can enhance the stability of GO aqueous dispersions at high density,simultaneously ensuring friction decrease and anti-wear *** is attributed to the stable nematic network by the ordered GO *** ordered assembly structure bears vertical shear force,therefore,reducing the *** is also assumed that the wide lateral size of graphene oxide promotes the nematic phase thus smoothes the graphene oxide film composed spontaneously under the coincidence of lamellar liquid crystal and 2D layered *** this work,the interlayer lubrication of GO was optimized,and the problem of GO dispersion sedimentation was solved by *** range of interfacial lubrication of GO aqueous dispersion has been expanded and the synergistic effect is conducive to the environmentally friendly lubricants.

关键词： lyotropic liquid crystal graphene oxide aqueous lubrication tribological behavior

Mass transfer in heap leaching of weathered crust elution deposited rare earth ore with Al_(2)(SO_(4))_(3) solution

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Journal of Rare Earths 2024年第6期42卷 1175-1181,I0007页

作者： Jingqun Yin Dedong zeng Jun Tian Yaqing Weng Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang330096China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang330031China

In order to increase efficiency and avoid Nh^(4+)-N pollution in the leaching process of weathered crust elution-deposited rare earth ores,the mass transfer in heap leaching with Al_(2)(SO_(4))_(3) solution was simulated with column elution and experimentally *** results indicate that the leaching yield is also up to 99%for leaching with aluminum sulfate instead of ammonium *** optimal flow rate is 60 mL/h,the height equivalent to a theoretical plate(hETP)is 1.29 mm *** peak value position of RE^(3+)is 60 mL/h,Fe^(3+)is 100 mL/h,however,Al^(3+)is 150 mL/h,and the heap leaching process has kinetic separation effect.

关键词： Raree arths Mass transfer Process optimization heapleaching Weathered crust elution-deposited rare earth ore

Parameterization of height-diameter and crown radius-diameter relationships across the globe

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Journal of Plant Ecology 2024年第2期17卷 36-48页

作者： Xiang Song Jinxu Li Xiaodong zeng International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Mathematics and Statistics North China University of Water Resources and Electric PowerZhengzhou 450046China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The tree height-diameter at breast height(h-DBh)and crown radius-DBh(CR-DBh)relationships are key for forest carbon/biomass estimation,parameterization in vegetation models and vegetation-atmosphere *** the h-DBh relationship has been widely investigated on site or regional scales,and a few of studies have involved CR-DBh relationships based on plot-level data,few studies have quantitatively verifed the universality of these two relationships on a global *** study evaluated the ability of 29 functions to ft the h-DBh and CR-DBh relationships for six different plant functional types(PFTs)on a global scale,based on a global plant trait *** showed that most functions were able to capture the h-DBh relationship for tropical PFTs and boreal needleleaf trees relatively accurately,but slightly less for temperate PFTs and boreal broadleaf trees(BB).For boreal PFTs,the S-shaped Logistic function ftted the h-DBh relationship best,while for temperate PFTs the Chapman-Richards function performed *** tropical needleleaf trees,the fractional function of DBh satisfactorily captured the h-DBh relationship,while for tropical broadleaf trees,the Weibull function and a composite function of fractions were the best *** CR-DBh,the ftting capabilities of all the functions were comparable for all PFTs except *** Logistic function performed best for two boreal PFTs and temperate broadleaf trees,but for temperate needleleaf trees and two tropical PFTs,some exponential functions demonstrated higher *** work provides valuable information for parameterization improvements in vegetation models and forest feld investigations.

关键词： tree height diameter at breast height crown radius ftting function parameterization vegetation model

Second-order error analysis of the averaged L1 scheme L1 for time-fractional initial-value and subdiffusion problems

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Science China Mathematics 2024年第7期67卷 1641-1664页

作者： Jinye Shen Fanhai zeng Martin Stynes School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China School of Mathematics Shandong UniversityJinan250100China Applied and Computational Mathematics Division Beijing Computational Science Research CenterBeijing100193China

Fractional initial-value problems(IVPs) and time-fractional initial-boundary value problems(IBVPs), each with a Caputo temporal derivative of order α ∈(0, 1), are considered. An averaged variant of the well-known L1 scheme is proved to be O(N^(-2)) convergent for IVPs on suitably graded meshes with N points, thereby improving the O(N^(-(2-α))) convergence rate of the standard L1 scheme. The analysis relies on a delicate decomposition of the temporal truncation error that yields a sharp dependence of the order of convergence on the degree of mesh grading used. This averaged L1 scheme can be combined with a finite difference or piecewise linear finite element discretization in space for IBVPs, and under a restriction on the temporal mesh width, one gets again O(N^(-2)) convergence in time, together with O(h^(2)) convergence in space,where h is the spatial mesh width. Numerical experiments support our results.

关键词： time-fractional subdiffusion averaged L1 scheme

Bhlhe40 protects cochlear hair cell-like hEI-OC1 cells against h_(2)O_(2) ‑triggered oxidative injury

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BIOCELL 2024年第6期48卷 991-999页

作者： LITING WEN XIAOXIA zeng PEIXIONG ChEN DAPENG ZhAO YANGYANG LI XIANhAI zeng Department of Otorhinolaryngology Longgang Otorhinolaryngology Hospital and Shenzhen Key Laboratory of OtorhinolaryngologyShenzhen Institute of OtorhinolaryngologyShenzhenChina

Background:Cochlear hair cell injury is a common pathological feature of hearing *** basic helix-loop-helix family,member e40(Bhlhe40),a gene belonging to the basic helix-loop-helix(bhLh)family,exhibits strong transcriptional repression ***:Oxidative damage,in house Ear Institute-Organ of Corti 1(hEI-OC1)cells,was caused using hydrogen peroxide(h2O2).The Ad-Bhlhe40 particles were constructed to overexpress Bhlhe40 in hEI-OC1 *** assays including cell counting kit-8(CCK-8),terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay(TUNEL),ﬂow cytometry,immunoﬂuorescence,and corresponding commercial kits were employed to investigate the impacts of Bhlhe40 on cell viability,apoptosis,oxidative stress levels,mitochondrial membrane potential and cellular ***,a dual-luciferase reporter assay was performed to conﬁrm the targeting of the histone deacetylases 2(hdac2)by ***:The results revealed that Bhlhe40 was downregulated in h_(2)O_(2)-treated hEI-OC1 cells,but its overexpression improved cell viability and mitigated h_(2)O_(2)-induced oxidative injury in hEI-OC1 cells with increase of superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GPx)activities and decrease of reactive oxygen species(ROS)***,overexpression of Bhlhe40 suppressed h_(2)O_(2)-triggered cell senescence,as evidenced by the fact that the upregulation of P53,P21,and P16 in hEI-OC1 cells treated with h2O2 were all alleviated by Bhlhe40 *** we further veriﬁed that overexpression of Bhlhe40 could inhibit the expression of hdac2,which may be related to the repression of hdac2 ***:This study suggests that Bhlhe40 plays a protective role against senescence and oxidative damage in cochlear hair cells exposed to h2O2.

关键词： Bhlhe40 Oxidative injury Cochlear hair cell histone deacetylases 2