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Science China Chemistry 2023年第10期66卷 2780-2784页

作者： Xuesen Hou Yong Lu youxuan ni Dongmei Zhang Qing Zhao Jun Chen Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

Oxocarbons(C_(n)O_(n),n=3,4,5,6,...)are a series of compounds that are only composed of carbonyl groups.The highly electrophilic carbon atoms in C_(n)O_(n)make their poor stability toward H_(2)O,and thus the synthesis of C_(n)O_(n)is very challenging.Here an oxidation-dehydration method is developed to successfully synthesize C_(4)O_(4)and C_(5)O_(5).The combination of nuclear magnetic resonance(^(13)C NMR,^(1)H NMR),mass spectra,and infrared spectra unambiguously proves the exact chemical structure of C_(4)O_(4)and C_(5)O_(5).When used as a cathode material in lithium-ion batteries(LIBs),C_(5)O_(5)could deliver a high discharge capacity of 698m Ah g-1(corresponding to an energy density of 1,256 Wh kg-1C_(5)O_(5)).Furthermore,ex-situ infrared spectra and density functional theory(DFT)calculations demonstrate that the carbonyl groups are redox active sites during discharge and charge processes.This work paves the way to achieve the synthesis and battery application of oxocarbons.

关键词： oxocarbons C_(4)O_(4) C_(5)O_(5) organic cathode lithium-ion batteries

Cell-nucleus structured electrolyte for low-temperature aqueous zinc batteries

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能源化学:英文版 2023年第8期83卷 324-332,I0010页

作者： Yang Dong ning Zhang Zhaodong Wang Jinhan Li youxuan ni Honglu Hu Fangyi Cheng Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Engineering Research Center of High-efficiency Energy Storage(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China College of Chemistry and Materials Science Analytical Science and Technology of Hebei ProvinceHebei UniversityBaoding 071002HebeiChina

Rechargeable aqueous zinc(Zn) batteries hold great promise for large-scale energy storage,but their implementation is plagued by poor Zn reversibility and unsatisfactory low-temperature performance.Herein,we design a cell-nucleus structured electrolyte by introducing low-polarity 1,2-dimethoxyethane(DME) into dilute 1 M zinc trifluoromethanesulfonate(Zn(OTf)_(2)) aqueous solution,which features an OTf--rich Zn2^(+)-primary solvation sheath(PSS,inner nucleus) and the DMEmodulated Zn^(2+)-outer solvation sheath(outer layer).We find that DME additives with a low dosage do not participate in the Zn2+-PSS but reinforce the Zn-OTf-coordination,which guarantees good reaction kinetics under ultralow temperatures.Moreover,DME breaks the original H-bonding network of H2O,depressing the freezing point of electrolyte to-52.4℃.Such a cell-nucleus-solvation structure suppresses the H_(2)O-induced side reactions and forms an anion-derived solid electrolyte interphase on Zn and can be readily extended to 1,2-diethoxyethane.The as-designed electrolyte enables the Zn electrode deep cycling stability over 3500 h with a high depth-of-discharge of 51.3% and endows the Zn‖V_(2)O_(5)full battery with stable cycling over 1000 cycles at 40℃.This work would inspire the solvation structure design for low-temperature aqueous batteries.

关键词： Aqueous zinc batteries Low temperature Cell-nucleus solvation structure Zn metal anode Solid electrolyte interphase

Biaxial strained dual-phase palladium-copper bimetal boosts formic acid electrooxidation

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Nano Research 2022年第1期15卷 280-284页

作者： Jiarun Geng Zhuo Zhu youxuan ni Haixia Li Fangyi Cheng Fujun Li Jun Chen Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China

Surface strain engineering is considered as an effective strategy to promote the electrocatalytic properties of noble metal nanocrystals.Herein,we construct a dual-phase palladium-copper(DP-PdCu)bimetallic electrocatalyst with remarkable biaxial strain via a one-pot wet-chemical approach for formic acid oxidation.The biaxial strain originates from the lattice mismatch between the disordered face-centered cubic(FCC)phase and ordered body-centered cubic(BCC)phase in each of DP-PdCu:nanoparticles.The proportion of FCC and BCC phases and size of PdCu nanoparticles are dependent on the addition amount of:capping agent,cetyltrimethylammonium bromide(CTAB).Density functional theory calculations reveal the downshift of d-band:center of Pd atoms due to the interfacial strain,which weakens the adsorption strength of undesired intermediates.These merit the,DP-PdCu catalyst with superior mass activity of 0.55 A·mg_(pd)^(-1) and specific activity of 1.91 mA·cm_(pd)^(-2) toward formic acid oxidation,outperforming the single FCC/EICC PdCu and commercial Pd/C catalysts.This will provide new insights into the structure design of high-performance electrocatalysts via strain engineering.

关键词： palladium-copper dual phase biaxial strain formic acid oxidation size-dependence

Recent progress in MnBi2nTe3n+1 intrinsic magnetic topological insulators: crystal growth, magnetism and chemical disorder

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National Science Review 2024年第2期11卷 65-80页

作者： Chaowei Hu Tiema Qian ni ni Department of Physics and Astronomy and California Nano Systems Institute University of California-Los Angeles

The search for magnetic topological materials has been at the forefront of condensed matter research for their potential to host exotic states such as axion insulators, magnetic Weyl semimetals, Chern insulators,etc. To date, the MnBi2nTe3n+1family is the only group of materials showcasing van der Waals-layered structures, intrinsic magnetism and non-trivial band topology without trivial bands at the Fermi level. The interplay between magnetism and band topology in this family has led to the proposal of various topological phenomena, including the quantum anomalous Hall effect, quantum spin Hall effect and quantum magnetoelectric effect. Among these, the quantum anomalous Hall effect has been experimentally observed at record-high temperatures, highlighting the unprecedented potential of this family of materials in fundamental science and technological innovation. In this paper, we provide a comprehensive review of the research progress in this intrinsic magnetic topological insulator family, with a focus on single-crystal growth, characterization of chemical disorder, manipulation of magnetism through chemical substitution and external pressure, and important questions that remain to be conclusively answered.

关键词： MnBi2Te4 magnetic topological insulator magnetism tuning antiferromagnetism ferromagnetism pressure chemical doping

Ultrafine RuO_(2) nanoparticles/MWCNTs cathodes for rechargeable Na-CO_(2) batteries with accelerated kinetics of Na_(2)CO_(3) decomposition

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Chinese Chemical Letters 2023年第3期34卷 531-535页

作者： Zhenzhen Wang Yichao Cai youxuan ni Yong Lu Liu Lin Haoxiang Sun Haixia Li Zhenhua Yan Qing Zhao Jun Chen Haihe Laboratory of Sustainable Chemical Transformations Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Renewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China

Na-CO_(2) batteries have attracted extensive attention due to their high theoretical energy density(1125 Wh/kg),efficient utilization of CO_(2),and abundant sodium resources.However,they are trapped by the sluggish decomposition kinetic of discharge products (mainly Na_(2)CO_(3)) on cathode side during the charging process.Here we prepared a series of nano-composites composed of RuO_(2) nanoparticles in situ loaded on activated multi-walled carbon nanotubes (RuO_(2)@a-MWCNTs) through hydrolyzing reaction followed by calcination method and used them as cathode catalysts to accelerate the decomposition of Na_(2)CO_(3).Among all catalysts,the RuO_(2)@a-MWCNTs with appropriate ratio of RuO_(2)(49.7 wt%) demonstrated best stability and rate performance in Na-CO_(2) batteries,benefiting from both high specific surface area (160.3 m^(2)/g) and highly dispersed RuO_(2) with ultrafine nanostructures (~2 nm).At a limited capacity of 500 mAh/g,Na-CO_(2) batteries could afford the operation of over 120 cycles at 100 mA/g,and even at the current density to 500 mA/g,the charge voltage was still lower than 4.0 V after 40 cycles.Further theoretical calculations proved that RuO_(2) was the catalytically active center and contributed to the decomposition of Na_(2)CO_(3) by weakening the C=O bond.The synergetic functions of high specific surface(CNTs) and high catalytic activity (RuO_(2)) will inspire more progress on metal-CO_(2) batteries.

关键词： Na-CO_(2)batteries Cathode catalyst RuO_(2)@a-MWCNTs High rate performance Low charge overpotential

Theoretical optimization of micropillar arrays for structurally stable bioinspired dry adhesives

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 124-129页

作者： Ke ni Zhengzhi Wang Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518108China

Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive surfaces.The micropillar arrays are composed of the resin pillars for adhesion and the substrate with different elastic modulus for supporting.The stress singularity at the bi-material corner between the pillars and the substrate can induce the failure of the micropillar-substrate corner and further hinder the fabrication and application of micropillar arrays,yet the design for the stability of the micropillar array lacks systematical and quantitative guides.In this work,we develop a semi-analytical method to provide the full expressions for the stress distribution within the bi-material corner combining analytical derivations and numerical calculations.The predictions for the stress within the singularity field can be obtained based on the full expressions of the stress.The good agreement between the predictions and the FEM results demonstrates the high reliability of our method.By adopting the strain energy density factor approach,the stability of the pillar-substrate corner is assessed by predicting the failure at the corner.For the elastic mismatch between the pillar and substrate given in this paper,the stability can be improved by increasing the ratio of the shear modulus of the substrate to that of the micropillar.Our study provides accurate predictions for the stress distribution at the bi-material corner and can guide the optimization of material combinations of the pillars and the substrate for more stable bioinspired dry adhesives.

关键词： Micropillar array Stability Bi-material corner Dry adhesive

Regional features of pollen R-values in China

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Science China Earth Sciences 2024年第1期67卷 295-308页

作者： Jie XIA Jian ni College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain Observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary palynology.The R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern vegetation.This study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and 2021.The dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 genera.Synthesizing the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific scale.Evidently,pollen R-value variations across China are statistically significant.Approximately two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within China.In the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and precipitation.Conversely,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased aridity.Nevertheless,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying vegetation types and climatic conditions.This hi

关键词： Pollen R-value Modern pollen-vegetation relationship Regional pattern Variability Paleovegetation reconstruction

Oligomerization of drug transporters:Forms,functions,and mechanisms

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1924-1938页

作者： Chunxu ni Mei Hong College of Life Sciences South China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms South China Agricultural UniversityGuangzhou 510642China

Drug transporters are essential players in the transmembrane transport of a wide variety of clinical drugs.The broad substrate spectra and versatile distribution pattern of these membrane proteins infer their pharmacological and clinical significance.With our accumulating knowledge on the three-dimensional structure of drug transporters,their oligomerization status has become a topic of intense study due to the possible functional roles carried out by such kind of post-translational modification(PTM).In-depth studies of oligomeric complexes formed among drug transporters as well as their interactions with other regulatory proteins can help us better understand the regulatory mechanisms of these membrane proteins,provide clues for the development of novel drugs,and improve the therapeutic efficacy.In this review,we describe different oligomerization forms as well as their structural basis of major drug transporters in the ATP-binding cassette and solute carrier superfamilies,summarize our current knowledge on the influence of oligomerization for protein expression level and transport function of these membrane proteins,and discuss the regulatory mechanisms of oligomerization.Finally,we highlight the challenges associated with the current oligomerization studies and propose some thoughts on the pharmaceutical application of this important drug transporter PTM.

关键词： Drug development Drug transporters Oligomerization Protein expression Protein–protein interaction Regulatory mechanism Structural basis Transport function

Advances in non-invasive imaging of proteinopathies in animal models of neurodegenerative diseases

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Neural Regeneration Research 2024年第10期19卷 2115-2116页

作者： Lei Cao Bin Ji Ruiqing ni Changes Technology Corporation Ltd. ShanghaiChina Fudan University ShanghaiChina School of Pharmacy Fudan UniversityShanghaiChina Institute for Biomedical Engineering University of Zurich&ETH Zurich Institute for Regenerative MedicineUniversity of ZurichZurichSwitzerland

Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseases is the aberrant cerebral accumulation of pathological protein aggregates,affecting selectively vulnerable circuits in a disease-specific pattern.Earlier studies have established a relationship between abnormal aggregation and neuronal dysfunction or loss,suggesting multifactorial pathogenesis mechanisms in these neurodegenerative disorders.

关键词： diseases degenerative clinical

High-throughput and simultaneous inertial separation of tumor cells and clusters from malignant effusions using spiral-contraction-expansion channels

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Microsystems & Nanoengineering 2024年第2期10卷 91-99页

作者： Zhixian Zhu Hui Ren Dan Wu Zhonghua ni Nan Xiang School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical InstrumentsSoutheast University211189NanjingChina School of Mechanical Technology Wuxi Institute of TechnologyNo.1600 Gaolang West Road214129WuxiChina Department of Oncology Jiangyin People’s Hospital214400JiangyinChina

Tumor cell clusters are regarded as critical factors in cancer pathophysiology,and increasing evidence of their higher treatment resistance and metastasis compared to single tumor cells has been obtained.However,existing cell separation methods that are designed for single tumor cells cannot be used to simultaneously purify tumor cell clusters.To address this problem,we demonstrated a microfluidic approach for the high-throughput,continuous-flow ternary separation of single tumor cells,tumor cell clusters,and WBCs from clinical pleural or abdominal effusions by coupling slanted spiral channels and periodic contraction-expansion arrays.We first systematically explored the influence of particle size and flow rate on particle focusing.The separation performance indicated that 94.0%of WBCs were removed and more than 97%of MDA-MB-231 tumor cells were recovered at a high flow rate of 3500µL/min.Moreover,more than 90%of tumor cell clusters were effectively preserved after separation.Finally,we successfully applied our device for the ternary separation of single tumor cells,tumor cell clusters,and WBCs from different malignant effusions collected from patients with metastatic cancer.Thus,our spiral-contraction-expansion device has potential as a sample pretreatment tool for the cytological diagnosis of malignant effusions.

关键词： separation contraction removed