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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 648-664页

作者： Zhaochen Yu Kaixuan Feng Shuyun Deng Yang Chen Hong Yan Honggun Song Chao Luo Zhi Hu School of advanced Manufacturing Nanchang UniversityNanchang330031China institute for advanced study Nanchang UniversityNanchang330031China

The phosphate protective film and micro-galvanic corrosion of biological Mg-3Zn-xNd (x = 0, 0.6, 1.2) alloys were investigated by scanning and transmission electron microscopy, quasi-in-situ observation, scanning Kelvin probe force microscopy (SKPFM) and electrochemical tests. The results revealed the Mg-Zn-Nd phases formed in Mg-3Zn alloy contained with Nd. Adding Nd resulted in a significant decline in the cracks of the phosphate protective film and micro-galvanic corrosion of alloys, which were recorded by quasi-in-situ observation. In addition, the Volta potential difference of Mg-Zn-Nd/α-Mg (~ 188 mV) was lower than MgZn/α-Mg (~ 419 mV) and Zn-rich/α-Mg (~ 260 mV), and the corrosion rates of alloys markedly decreased after the addition of 0.6 wt% Nd. The improvement in corrosion resistance of Nd-containing alloys was mainly attributed to the following: (i) the addition of Nd reduced the Volta potential difference (second phases/α-Mg);(ii) the phosphate protective film containing Nd_(2)O_(3) deposited on the surface of the alloys, effectively preventing the penetration of harmful anions.

关键词： Magnesium alloys Quasi-in-situ observation Phosphate protective film Scanning Kelvin probe force microscopy(SKPFM) Micro-galvanic corrosion

Modulating the alloying mode in the doping-induced synthesis of Au-Pd nanowires

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Nano Research 2024年第4期17卷 3334-3343页

作者： Hui Jin Xiaoliang Wei Lecheng Zhao Jialong Yu Qiao Pan Shumin Li Qian Wang Zhaotong Yuan Dan Yang Donghui Zhao Hongyu Chen Yawen Wang institute of advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergistic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310064China institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310064China

Heterogeneous doping is one effective strategy for synthesizing metal alloy nanowires.Herein,the heterogeneous doping processes of Pd on the ultrathin Au nanowires were systematically modulated and investigated.Au-Pd alloy nanowires with various morphologies and lattice structures can be obtained by adjusting the morphology of the precursor Au nanowires and the kinetics of the heterogeneous doping processes.The effects of the rate of Pd reduction and the concentration of the ligand oleylamine(OAm)on the Pd deposition and alloying mode were articulated.Generally,as the Pd deposition rate decreases,the Pd deposition and alloying mode switches from the island-forming Stransky–Krastanov(SK)mode to the epitaxial Frank-van der Merwe(FM)mode,and eventually to an unconventional twisting alloying mode,where the interdiffusion of Pd and Au causes drastic rearrangement of the lattice structure and formation of helical structures.The kinetics-related variation of alloying mode could also be observed in the Au-Ag nanowires,demonstrating a general design principle for the synthesis of alloy nanostructures.In addition,the electrocatalytic performance of various Au-Pd nanowires was evaluated,and the alloy nanowire formed via the SK mode was found to be an excellent electrocatalyst for oxygen reduction and ethanol oxidation.

关键词： gold nanowires Au-Pd alloy oleylamine post-synthetic modification

A Symmetric-Actuating Linear Piezoceramic Ultrasonic Motor Capable of Producing a Scissoring Effect

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Research 2024年第1期2023卷 571-581页

作者： Zhanmiao Li Xingyu Yi Rongqi Zhu Zhonghui Yu Xiaoting Yuan MohammadJavad PourhosseiniAsl Shuxiang Dong School of Materials Science and Engineering Peking UniversityBeijing 100871China College of Mechatronics and Control Engineering and Institute for Advanced StudyShenzhen UniversityShenzhen 518051China

Conventionally,to produce a linear motion,one motor’s stator is employed to drive one runner moving forward or backward.So far,there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions,while this function is desired for precise scissoring and grasping in the minimally invasive surgery field.Herein,we report a brandnew symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission mechanisms.The key component of the motor is an(2×3)arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal(L_(1))and third bending(B_(3))modes,leading to symmetric elliptical vibration trajectories at its two ends.A pair of microsurgical scissors is used as the end-effector,demonstrating a very promising future for high-precision microsurgical operations.

关键词： field symmetric backward

Regulatory role of peroxynitrite in advanced glycation end products mediated diabetic cardiovascular complications

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World Journal of Diabetes 2024年第3期15卷 572-574页

作者： Asis Bala Pharmacology and Drug Discovery Research Laboratory Division of Life SciencesInstitute of Advanced Study in Science and TechnologyGuwahati 781035AssamIndia

The advanced Glycation End Products(AGE)binding with its receptor can increase reactive oxygen species(ROS)generation through specific signaling mediators.The effect of superoxide(O2-)and O2-mediated ROS and reactive nitrogen species depends on their concentration and location of formation.Nitric oxide(NO)has anti-inflammatory and anticoagulant properties and a vasodilation effect,but NO can be deactivated by reacting with O_(2)^(-).This reaction between NO and O2-produces the potent oxidant ONOO−.Therefore,ONOO-'s regulatory role in AGEs in diabetic cardiovascular complications must considered as a regulator of cardiovascular complications in diabetes.

关键词： Diabetes Cardiovascular complication advanced glycation end products Reactive oxygen species Reactive nitrogen species Peroxynitrite

RNPS1 stabilizes NAT10 protein to facilitate translation in cancer via tRNA ac^(4)C modification

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International Journal of Oral Science 2024年第1期16卷 73-84页

作者： Xiaochen Wang Rongsong Ling Yurong Peng Weiqiong Qiu Demeng Chen Center For Translational Medicine the First Affiliated HospitalSun Yat-sen UniversityGuangzhouChina institute for advanced study Shenzhen UniversityShenzhenChina

Existing studies have underscored the pivotal role of N-acetyltransferase 10(NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma(HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1(RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6(ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac^(4)C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel t RNA-ac^(4)C modification sites, thereby providing a potent sequencing tool for tRNAac^(4)C research. Our findings expand the repertoire of tRNA ac^(4)C modifications and identify a role of tRNA ac^(4)C in the regulation of mRNA translation in HNSCC.

关键词： NAT1 thereby translation

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Mirror symmetry for special nilpotent orbit closures In Memory of Professor Gang Xiao

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Science China Mathematics 2024年

作者： Baohua Fu Yongbin Ruan Yaoxiong Wen AMSS HLM and MCM Chinese Academy of Sciences Korea institute for advanced study institute for advanced study in Mathematics Zhejiang University School of Mathematical Sciences University of Chinese Academy of Sciences

Motivated by geometric Langlands, we initiate a program to study the mirror symmetry between nilpotent orbit closures of a semisimple Lie algebra and those of its Langlands dual. The most interesting case is Bn via Cn. Classically, there is a famous Springer duality between special orbits. Therefore, it is natural to speculate that the mirror symmetry we seek may coincide with Springer duality in the context of special orbits.Unfortunately, such a naive statement fails. To remedy the situation, we propose a conjecture which asserts the mirror symmetry for certain parabolic/induced covers of special orbits. Then, we prove the conjecture for Richardson orbits and obtain certain partial results in general. In the process, we reveal some very interesting and yet subtle structures of these finite covers, which are related to Lusztig’s canonical quotients of special nilpotent orbits. For example, there is a mysterious asymmetry in the footprint or range of degrees of these finite covers. Finally, we provide two examples to show that the mirror symmetry fails outside the footprint.

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A weighted maximal Lestimate of operator-valued Bochner-Riesz means

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Acta Mathematica Sinica,English Series 2024年

作者： Guixiang HONG Liyuan ZHANG institute for advanced study in Mathematics Harbin Institute of Technology School of Mathematics and Statistics Wuhan University

In this paper, we establish a weighted maximal L2estimate of operator-valued Bochner-Riesz means. The proof is based on noncommutative square function estimates and a sharp weighted noncommutative Hardy-Littlewood max...

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Facet-dependent transformation and toxicity of nanoscale zinc oxide in the synthetic saliva

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Journal of Environmental Sciences 2024年第5期139卷 170-181页

作者： Xiang Zhang Yunpeng Huang Jikun Wang Jie Tang YangMei Nali Zhu Zhigang Li Lingxiangyu Li YaweiWang School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Systems Health Science of Zhejiang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Chemistry University of PennsylvaniaPhiladelphia 19104USA

The nanoscale zinc oxide(n-ZnO)was used in food packages due to its superior antibac terial activity,resulting in potential intake of n-ZnO through the digestive system,wherein n-ZnO interacted with saliva.In recent,facet engineering,a technique for controlling the exposed facets,was applied to n-ZnO,whereas risk of n-ZnO with specific exposed facets in saliva was ignored.ZnO nanoflakes(ZnO-0001)and nanoneedles(ZnO-1010)with the pri mary exposed facets of{0001}and{1010}respectively were prepared in this study,investigat ing stability and toxicity of ZnO-0001 and ZnO-1010 in synthetic saliva.Both ZnO-0001 and ZnO-1010 partially transformed into amorphous Zn_(3)(PO_(4))_(2)within 1 hr in the saliva even containing orgnaic components,forming a ZnO-Zn_(3)(PO_(4))_(2)core-shell structure.Neverthe less,ZnO-1010 relative to ZnO-0001 would likely transform into Zn_(3)(PO_(4))_(2),being attributed to superior dissolution of{1010}facet due to its lower vacancy formation energy(1.15 eV than{0001}facet(3.90 eV)).The toxicity of n-ZnO to Caco-2 cells was also dependent on the primary exposed facet;ZnO-0001 caused cell toxicity through oxidative stress,whereas ZnO-1010 resulted in lower cells viability than ZnO-0001 through oxidative stress and mem brane damage.Density functional theory calculations illustrated that·O_(2)^(-)was formed and released on{1010}facet,yet O_(2)^(2-)instead of·O_(2)^(-)was generated on{0001}facet,leading to low oxidative stress from ZnO-0001.All findings demonstrated that stability and toxicity of n-ZnO were dependent on the primary exposed facet,improving our understanding o health risk of nanomaterials.

关键词： The exposed facet Nanoscale ZnO Chemical transformation Synthetic salica Nanotoxicity

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Identifying the Active Site of Water Oxidation Catalyst Based on Defective Fe-Doped Ni Oxyhydroxide

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CCS Chemistry 2024年第2期6卷 365-376页

作者： Yunxuan Ding Jian Du Tao Wang Licheng Sun institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024 Center of Artificial Photosynthesis for Solar Fuels Department of ChemistrySchool of ScienceWestlake UniversityHangzhou 310024

Electrochemical water splitting plays a crucial role in storing sustainable energy into H2 as an ideal fuel,in which the anodic oxygen evolution reaction(OER)is the bottleneck.Currently,Fe-doped NiOOH(Ni_(1−x)Fe_(x)OOH)is a promising OER catalyst under alkaline conditions.However,the specific active sites responsible for their good performances remain debatable.Here,we identify a nickel-oxygen radical(Ni–O·)and an iron-oxo(Fe=O)group as two essential states for adsorbed oxygen.Meanwhile,both thermochemical O–O coupling and electrochemical OER elementary steps are considered on the Ni_(1−x)Fe_(x)OOH catalysts.Sophisticated mechanistic studies with a combined density functional theory simulation and experimental analysis unravel that both the Ni and Fe centers can act as the active sites for the defective Ni_(1−x)Fe_(x)OOH to catalyze OER,depending on the nature of the defect.The presence of Fe can benefit the stabilization of the defective surface and influence the electronic property of the nearby Ni site.This work not only identifies the intrinsic active sites of Ni_(1−x)Fe_(x)OOH,but also illustrates the essential roles of defects in catalysis,which sheds light on the design of more efficient OER catalysts in the future.

关键词： defect water nucleophilic attack oxygen evolution reaction heterogeneous catalysis density functional calculations

In-situ AFM and quasi-in-situ studies for localized corrosion in Mg-9Al-1Fe-(Gd) alloys under 3.5 wt.% NaCl environment

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Journal of Magnesium and Alloys 2024年第3期12卷 1170-1185页

作者： Junping Shen Tao Lai Zheng Yin Yang Chen Kun Wang Hong Yan Honggun Song Ruiliang Liu Chao Luo Zhi Hu School of advanced Manufacturing Nanchang UniversityNanchang 330031China institute for advanced study Nanchang UniversityNanchang 330031China Singapore Centre for Environmental Life Sciences Engineering Nanyang Technological University60 Nanyang Drive 637751Singapore

Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance.The reliable monitor should be high distinguishability and real-time in liquid environment.Herein,Mg-9Al-1Fe and Mg-9Al-1Fe-1Gd alloys were designed to highlight the impact of intermetallic on the corrosion behaviour.In-situ AFM with a special electrolyte circulation system and quasi-in-situ SEM observation were used to monitor the corrosion process of the designed alloys.SEM-EDS and TEM-SAED were applied to identify the intermetallic in the designed alloys,and their volta potentials were measured by SKPFM.According to the real-time and real-space in-situ AFM monitor,the corrosion process consisted of dissolution of anodicα-Mg phase,accumulation of corrosion products around cathodic phase and shedding of some fine cathodic phase.Then,the localized corrosion process of Mg alloy was revealed combined with the results of the monitor of corrosion process and Volta potential difference.

关键词： Magnesium Localized corrosion In-situ AFM SKPFM Corrosion behaviour.

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