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Nano Research 2024年第6期17卷 4844-4849页

作者： Chang Liu Zongnan Wei Minna Cao Rong Cao State Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science and Technology Innovation laboratory for Optoelectronic Information of China Fuzhou 350108China

The development of effective and stable electrocatalysts for the hydrogen evolution reaction(HER)in acidic electrolytes is a significant *** this work,homogeneous Pt nanodendrites(Pt NDs)with a PtIr shell were successfully synthesized by a two-step wet chemical *** open three-dimensional(3D)dendritic structure exhibited exceptional electrocatalytic characteristics,exposing as many active sites as ***,by alloying Ir with Pt on the surface,catalytic activity was greatly enhanced while ensuring extremely high *** surface-enriched platinum nanodendritic catalysts(Pt@PtIr NDs)outperformed the control samples and the commercial *** acidic HER test,Pt@PtIr NDs had a lower overpotential(22 mV)than Pt NDs(26 mV)and commercial Pt/C(31 mV)at 10 mA/cm^(2),and the activity of Pt@PtIr NDs remained consistent even after undergoing a continuous durability test for at least 168 h,which was much superior to the performance of commercial Pt/C(10 h)under identical test *** study revealed that the application of 3D Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER.

关键词： Pt nanodendrites iridium high stability hydrogen evolution reaction alloy

Differentiated self-assembly through orthogonal noncovalent interactions towards the synthesis of two-dimensional woven supramolecular polymers

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Chinese Chemical Letters 2024年第5期35卷 179-182页

作者： Zhenzhu Wang Chenglong Liu Yunpeng Ge Wencan Li Chenyang Zhang Bing Yang Shizhong Mao Zeyuan Dong State Key laboratory of Supramolecular structure and Materials College of ChemistryJilin UniversityChangchun 130012China Center for Supramolecular Chemical biology Jilin UniversityChangchun 130012China

Molecular weaving is a powerful approach to make molecularly woven materials that have showed unprecedented characteristics and properties intrinsically distinct to those of non-woven *** here report a facile and efficient approach for the synthesis of 2D woven supramolecular polymers by differentiated self-assembly through orthogonal noncovalent ***,the difference in binding strength of two orthogonal noncovalent interactions can be used to control the process of molecular ***,single-layered 2D woven supramolecular polymers were synthesized and fully characterized by various *** study demonstrates a controllable method for molecular weaving,and will significantly hasten the development of molecularly woven materials.

关键词： Differentiated self-assembly Double-stranded helix Molecular weaving Supramolecular chemistry Two-dimensional polymer

Pathologically relevant aldoses and environmental aldehydes cause cilium disassembly via formyl group-mediated mechanisms

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Journal of Molecular Cell biology 2024年第1期16卷 15-28页

作者： Te Li Min Liu Fan Yu Song Yang Weiwen Bu Kai Liu Jia Yang Hua Ni Mulin Yang Hanxiao Yin Renjie Hong Dengwen Li Huĳie Zhao Jun Zhou Haihe laboratory of Cell Ecosystem State Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Protein ScienceCollege of Life SciencesNankai UniversityTianjin 300071China laboratory of Tissue Homeostasis Haihe Laboratory of Cell EcosystemTianjin 300462China Center for Cell structure and Function Collaborative Innovation Center of Cell Biology in Universities of ShandongShandong Provincial Key Laboratory of Animal Resistance BiologyCollege of Life SciencesShandong Normal UniversityJinan 250014China

Carbohydrate metabolism disorders(CMDs),such as diabetes,galactosemia,and mannosidosis,cause ciliopathy-like multiorgan ***,the mechanistic link of cilia to CMD complications is still poorly ***,we describe significant cilium disassembly upon treatment of cells with pathologically relevant aldoses rather than the corresponding sugar ***,environmental aldehydes are able to trigger cilium disassembly by the steric hindrance effect of their formyl *** studies reveal that aldehydes stimulate extracellular calcium influx across the plasma membrane,which subsequently activates the calmodulin-Aurora A-histone deacetylase 6 pathway to deacetylate axonemal microtubules and triggers cilium *** vivo experiments further show that Hdac6 knockout mice are resistant to aldehyde-induced disassembly of tracheal cilia and sperm *** findings reveal a previously unrecognized role for formyl group-mediated cilium disassembly in the complications of CMDs.

关键词： carbohydrate metabolism disorder aldose aldehyde cilium disassembly formyl group calcium influx HDAC6

Development of EPDM composites reinforced by CNTs@SiO_(2)for thermal protection systems of aerospace propulsion:Significant improvement in oxidation and ablation resistance properties

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Chinese Journal of Aeronautics 2024年第2期37卷 471-481页

作者： Li WANG Jiang LI Kang LI Yiwei WANG Chenyang MA Science and Technology on Combustion Internal Flow and Thermal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072China

Carbon Nanotubes(CNTs)reinforced Polymer-Matrix Composites(PMCs)is widely used as insulation materials in thermal protection system of aerospace ***,CNTs are prone to oxidation and have high thermal conductivities,which makes it difficult to improve the ablation resistance of insulation materials that contain ***_(2)was encapsulated onto the surface of CNTs(CNTs@SiO_(2)),which were then added to Ethylene Propylene Diene Monomer(EPDM)rubber to prepare the insulation *** analysis and ablation test were used to evaluate the resistance of the insulation materials to thermal oxidation and ***,scanning electron microscopy was performed to analyze their *** revealed that the addition of CNTs@SiO_(2)could visibly reduce the effects of hot corrosion and ablation on insulation *** C-CNTs@SiO_(2)-1 formulation had the best ablative ***,compared with the unencapsulated formulation(C-CNTs-10),the C-CNTs@SiO_(2)-1 formulation reduced the line ablation rate by 51%to 0.0130 mm/s after oxygen-acetylene ***,the ablation mechanism was investigated based on the effects of the CNTs@SiO_(2)additive on their ***,the improvement in ablation performance may be attributed to CNTs@SiO_(2)-induced decreases in thermal conductivity,improvement in the hot corrosion resistance in the char layer,and changes in the microstructure.

关键词： Polymer-Matrix Composites(PMCs) Carbon Nanotubes(CNTs) Thermal properties Ablation Oxidation

Living/controlled polymerization of vinylpyridines into sequence-regulated copolymers by Lewis pair

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Science China Chemistry 2024年第8期67卷 2737-2746页

作者： Qiankun Ding Wuchao Zhao Fukuan Li Jianghua He Yuetao Zhang Department of State Key laboratory of Supramolecular structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). Mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. More importantly, by simply adjusting the LA dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.

关键词： guanidine phosphine Lewis pair polymerization living/controlled polymerization vinyl pyridine sequence regulation

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Pd cluster decorated free standing flexible cathode for high performance Li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： Liang Guo Guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu Xia Li Feng Dang Key laboratory for Liquid-Solid structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for Li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

A phase separation-fortified bi-specific adaptor for conditional tumor killing

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Science China(Life Sciences) 2024年第7期67卷 1385-1397页

作者： Yuyan Liu Yuting Zhu Weifan Xu Pilong Li State Key laboratory of Membrane biology Frontier Research Center for Biological StructureTsinghua University-Peking University Joint Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China

A common approach in therapeutic protein development involves employing synthetic ligands with multivalency,enabling sophisticated control of signal *** the emerging concept of liquid-liquid phase separation(LLPS)and its ability to organize cell surface receptors into functional compartments,we herein have designed modular ligands with phase-separation modalities to engineer programmable interreceptor communications and precise control of signal pathways,thus inducing the rapid,potent,and specific apoptosis of tumor *** their simplicity,these“triggers”,named phase-separated Tumor Killers(hereafter referred to as psTK),are sufficient to yield interreceptor clustering of death receptors(represented by DR5)and tumor-associated receptors,with notable features:LLPSmediated robust high-order organization,well-choreographed conditional activation,and broad-spectrum capacity to potently induce apoptosis in tumor *** development of novel therapeutic proteins with phase-separation modalities showcases the power of spatially reorganizing signal *** approach facilitates the diversification of cell fate and holds promising potential for targeted therapies against challenging tumors.

关键词： phase separation therapeutic proteins receptor-ligand interactions DR5 tumor apoptosis

Synthesis,structure,and luminescence properties of melilite Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7) phosphors for use in yellow light-emitting devices

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Journal of Rare Earths 2024年第8期42卷 1489-1495,I0003页

作者： Yunyun Liu Chuanxin Huang Meng Wang Xihu Wang Yan Wang Ju Gao School of Opto-Electronic Engineering Zaozhuang UniversityZaozhuang277160China Key laboratory of Functional Materials and Devices for Informatics of Anhui Educational Institutions Department of PhysicsFuyang Normal UniversityFuyang236037China Key laboratory of Optoelectronic Materials Chemisry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002.China

Dy^(3+) and Lu^(3+) co-doped CaLaGa_(3)O_(7) phosphors were prepared via high-temperature solid-phase *** electronic structures of LuxCaLa_(0.98-x)Ga_(3)O_(7) were investigated by the first-principles *** influence of Lu^(3+) on yellow light emission was studied using X-ray diffraction(XRD)and photoluminescence(PL) *** XRD results indicate that compared to Dy^(3+):CaLaGa_(3)O_(7),the cell parameters of Dy^(3+):LuCaLaGa_(3)O_(7) tend to decrease,which is due to the smaller radius of Lu^(3+).When pumped by blue GaN laser diode(LD),the emission peaks of phosphors with different Lu^(3+)doping concentrations in the visible region are similar,with the strongest peak at 574 nm in the yellow light region,which is sensitive to human *** optimal doping concentration of Lu^(3+) is confirmed to be1 at%,when all emission spectra and measured fluorescence lifetimes are taken into ***,the optimal phosphor composition Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)(x=0.01) has an internal quantum efficiency(IQE) of 46.94% and an external quantum efficiency(EQE) of 15.19%.Most notably,the prepared phosphor demonstrates excellent thermal stability and a high activation energy(0.203 eV).In addition,the International Illumination Commission color coordinates of the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7) phosphors are in the yellow light *** above analysis indicates that the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7)(x=0.001)phosphor has promising application prospects in yellow light-emitting devices.

关键词： Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)phosphors Yellow emission structure characteristics Luminescent properties Rare earths

Construction of metallo-complexes with 2,2′:6′,2″-terpyridine substituted triphenylamine in different modified positions and their photophysical properties

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Chinese Chemical Letters 2024年第7期35卷 301-305页

作者： Shengwen Guan Zhaotong Wei Ningxu Han Yude Wei Bin Xu Ming Wang Junjuan Shi State Key laboratory of Supramolecular structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The stable coordinated metallo-complexes based on 2,2′:6′,2″-terpyridine(tpy)and its derivatives have been widely researched for various wide-ranging applications in photoelectronics,catalysis,sensor,photoluminescence,and so ***,the most reported studies ignored the comprehensive comparison between structures modified by different positions and ***,we design a series of metallo-complexes which were assembled with tpy substituted triphenylamine(TPA)at different positions and metal ions and explored their photophysical *** the solution state,MLE_(2)based on the 5,5″-positions modification showed the highest PLQYs and PL *** the increase of solvent polarity,MLB2exhibit the largest *** the solid state,from MLA_(2)to MLE_(2),the emission colours are gradually red-shifted from yellow to *** findings in this work may pave a new way to design functional metallo-complexes,not just for PL properties.

关键词： Metallo-complexes 2,2′:6′,2″-terpyridine Triphenylamine Different modified positions Photophysical properties

Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory

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Journal of Central South University 2024年第7期31卷 2341-2364页

作者： LI Liang CHEN Jia-jun ZHAO Lian-heng HE Ke-pei HU Shi-hong LI Hua-long School of Civil Engineering Central South UniversityChangsha 410075China Key laboratory of Heavy-haul Railway Engineering structure Ministry of EducationCentral South UniversityChangsha 410075China Hunan Provincial Key laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering structure Central South UniversityChangsha 410075China

Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety ***,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal *** particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting *** analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling *** dilatancy angle-crushing zone size relationship exhibited nonmonotonic *** relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal *** the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed.

关键词： deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics