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Operando and reversible manipulation of Pt electrocatalytic properties through its substrate phase transition

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Science China Chemistry 2025年

作者： Hongfei Liu Yi Xie Changzheng wu Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceCollaborative Innovation Center of Chemistry for Energy Materials (iChEM)and CAS Center for Excellence in NanoscienceUniversity of Science and Technology of China Institute of Energy Hefei Comprehensive National Science Center

The lattice strain is considered critical for determining the catalytic activity of metal catalysts such as Pt. However, the dynamic manipulation of Pt lattice strain under reaction conditions to directly examine its catalytic effect has not been achieved. In this study, we realized the reversible manipulation of Pt electrocatalytic properties under electrochemical conditions by tuning the Pt lattice strain with the temperature-controlled Martensite-Austenite phase transition of the shape memory NiTi alloy *** enabled establishing a straightforward relationship between the strain-induced electronic structure transformation and electrocatalytic activity leaping. The binding strength between Pt and surface oxygen species was confirmed as the critical factor that dominated the hydrogen evolution and the oxygen reduction activities. In contrast, the oxygen evolution activity was barely affected by NiTi substrate phase transition.

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Quantum convolution inequalities on Frobenius von Neumann algebras

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Science China Mathematics 2025年

作者： Linzhe Huang Zhengwei Liu Jinsong wu Beijing Institute of Mathematical Sciences and Applications Yau Mathematical Sciences Center and Department of Mathematics Tsinghua University

In this paper, we introduce Frobenius von Neumann algebras and study quantum convolution inequalities. In this framework, we unify quantum Young's inequality on quantum symmetries such as subfactors,and fusion bi-algebras studied in quantum Fourier analysis. Moreover, we prove quantum entropic convolution inequalities and characterize the extremizers in the subfactor case. We also prove quantum smooth entropic convolution inequalities. We obtain the positivity of comultiplications of subfactor planar algebras, which is stronger than the quantum Schur product theorem. All these inequalities provide analytic obstructions of unitary categorification of fusion rings stronger than the Schur product criterion.

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他克莫司延缓移植性肾病进展的临床观察

肾脏病与透析肾移植杂志 2006年第2期15卷 127-129页

作者：刘静管德林息金泼黄真吴建臣赵勇周苏清华大学第一附属医院北京100016

目的:观察他克莫司(FK506)与霉酚酸酯(MMF)联合应用延缓移植性肾病肾功能进展的疗效。方法:选择肾移植术后肾功能异常,并经移植肾活检病理证实为慢性移植性肾病患者46例,将原环孢素A(CsA)切换为FK506,同时联合MMF和激素。FK506起始剂量0... 详细信息

目的:观察他克莫司(FK506)与霉酚酸酯(MMF)联合应用延缓移植性肾病肾功能进展的疗效。方法:选择肾移植术后肾功能异常,并经移植肾活检病理证实为慢性移植性肾病患者46例,将原环孢素A(CsA)切换为FK506,同时联合MMF和激素。FK506起始剂量0·08mg/(kg·d),MMF1.5g/d,监测切换12个月后血清肌酐、肾小球滤过率(GFR)[ml/(min·1·73m2)]、24h尿蛋白定量(g)变化。结果:切换为FK506治疗12个月后,平均血清肌酐由(293±45)μmol/L降至(198±24)μmol/L(P<0·05)。GFR由(39·77±2·35)ml/(min·1·73m2)提高至(49·87±3·17)ml/(min·1·73m2),24h尿蛋白定量由(4·8±0·8)g降至(1·9±0·7)g(P<0·05)。副作用包括高血糖(6例)、震颤(8例)、腹泻(4例)、白细胞减少(2例)、带状疱疹(1例)、骨痛(1例)。结论:FK506可以有效延缓移植肾病进展。

关键词：他克莫司肾移植肾小球滤过率血肌酐

秸秆还田与氮肥施用对稻田温室气体排放的影响

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生态学报 2024年第12期44卷 5328-5339页

作者：吴健成刘卿汪翠存陆汝华刘艳曹强田永超朱艳曹卫星刘小军南京农业大学国家信息农业工程技术中心南京210095 智慧农业教育部工程研究中心南京210095 农业农村部农作物系统分析与决策重点实验室南京210095 江苏省信息农业重点实验室南京210095 现代作物生产省部共建协同创新中心南京210095

秸秆还田与氮肥施用是农田生态系统中碳氮元素的两大主要补给途径,其在调控稻田甲烷(CH_(4))和氧化亚氮(N_(2)O)排放以及水稻产量方面具有重要作用。以往的研究主要关注秸秆还田或氮肥施用单因素对稻田温室气体排放的影响,而双因素互作... 详细信息

秸秆还田与氮肥施用是农田生态系统中碳氮元素的两大主要补给途径,其在调控稻田甲烷(CH_(4))和氧化亚氮(N_(2)O)排放以及水稻产量方面具有重要作用。以往的研究主要关注秸秆还田或氮肥施用单因素对稻田温室气体排放的影响,而双因素互作对甲烷和氧化亚氮排放的影响尚未明确。同时,在秸秆还田条件下如何进行合理的氮肥施用鲜有深入研究。本研究基于3个氮肥处理(0、180、360 kg N/hm^(2))和3个秸秆还田处理(0、2.25、3.75 t/hm^(2))进行多年水稻田间定位试验,研究结果表明:CH_(4)季节累积排放随秸秆还田量增加而增加,与施氮量无显著正相关关系;N_(2)O季节累积排放随施氮量增加而增加,与秸秆还田量无显著正相关关系;秸秆还田对于产量的影响具有不确定性,两年均在秸秆不还田+不施氮处理(S0N0)出现最低产量,2021与2022年最低产量分别为5740.64和4903.75 kg/hm^(2)。2021与2022年最高产量分别在秸秆不还田+高氮(S0N_(2))和高量秸秆还田+高氮(S2N_(2))出现,分别为10938.48和10384.83 kg/hm^(2)。同时,本研究发现在低量秸秆还田条件下,在碳足迹(CF, Carbon Footprint)方面,施氮量为251 kg N/hm^(2)时碳足迹达到最低点,为1.01 kg C/kg;而在生态经济净收益(NEEB, Net Ecosystem Economic Benefits)方面,施氮量为294 kg N/hm^(2)时生态经济净收益达到最高点,为11778.15元/hm^(2)。为协同生态经济净收益与碳排放,在低量秸秆还田(S1)下,配合251—294 kg N/hm^(2)的施氮量为最优施肥方案。研究结果为指导稻田温室气体减排、实现稻田碳中和以及农田管理提供了理论支撑,为实现水稻的高产稳产与低碳生产科学依据。

关键词：水稻温室气体秸秆还田氮肥推荐施肥

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Angular velocity estimation using characteristics of star trails obtained by star sensor for spacecraft

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Science China(Information Sciences) 2021年第1期64卷 201-214页

作者： Xiaolin NING Pingping CHEN Yueqing HUANG Weiren wu jiancheng FANG School of Instrumentation Science & Opto-electronics Engineering Beihang University Lunar Exploration and Space Program Center China National Space Administration

Many studies have been conducted about angular velocity estimation using star sensors, and fairly good performance is achieved when the spacecraft is working at low-dynamic environments. However,when the spacecraft rotates at a large angular velocity, the star image will become blurred, which makes it difficult to identify and recognize star centroids, which, in turn, reduces the accuracy of angular velocity estimation. Therefore, to solve the problem with angular velocity estimation in highly dynamic situations,this research studies a method of angular velocity estimation using blurred star images. The length and ending point coordinates of star trails obtained from these blurred star images are used for a series of processes, which includes the pre-processing of blurred star images, determination of starting and ending points, thinning and selection of star trails, and calculation of trail lengths. Simulations show that the effectiveness of the proposed method in highly dynamic situations and the angular velocity estimation errors in constant and sinusoidal variation are reduced by at least 66% and 62%, respectively, compared with those of the traditional method.

关键词： angular velocity estimation star sensor blurred star images star trail characteristics unscented Kalman filter

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie Liu Changqing Xu Da-Jian wu Ying Cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui Peng Peng wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film Growth Dynamics

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Nano-Micro Letters 2025年第2期17卷 387-400页

作者： Mengen Ma Cuiling Zhang Yujiao Ma Weile Li Yao Wang Shaohang wu Chong Liu Yaohua Mai Institute of New Energy Technology College of Physics&Optoelectronic EngineeringJinan UniversityGuangzhou 510632People’s Republic of China Key Laboratory of New Semiconductors and Devices of Guangdong Higher Education Institutes Jinan UniversityGuangzhou 510632People’s Republic of China Guangdong Mellow Energy Co. LimitedYuanming RoadZhuhai 519075GuangdongPeople’s Republic of China

Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating *** this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive *** then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air.

关键词： Gas quenching Additive distribution Buried passivation Blade coating Crystallization dynamics

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting Yang Guisheng Liang Yifeng Cheng Limin wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization