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Science China Chemistry 2025年第1期68卷 186-191页

作者： Hai Zou Yunfeng Bao Xueshang Xin Yu Qi Tengfeng Xie Fuxiang Zhang State Key laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029China College of Chemistry Jilin UniversityChangchun 130012China

Constructing typeⅡheterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated(oxy)nitrides with low thermal ***,we synthesized a homologous heterostructure(denoted as YTON_H)based on the oxynitrides of YTaO_(4-x)N_(y)and YTa ON_(2).This heterostructure exhibits type Ⅱ band structure alignment and intimate interface achieved through a magnesium(Mg)powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON_H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO_(4-x)N_(y)and YTaON_(2)).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light

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TRIM66-HP1γ remodels the chromatin through phase separation

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Biophysics Reports 2025年第01期11卷 18-33页

作者： Siyuan Shen Feng Chen Yifan Zhang Fudong Li Xuebiao Yao Dan Liu Yunyu Shi Liang Zhang Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of China Ministry of Education Key laboratory for Membraneless Organelles and Cellular dynamics University of Science and Technology of China Hefei national Research Center for Cross disciplinary Science University of Science and Technology of China

Chromatin contains not only heterochromatin(HC) and euchromatins(EC) but also facultative heterochromatin(f HC), which experience the dynamic remodeling between HCs and ECs by different regulators. The regulation of f HCs involves lots of different cell functions, like genomic stability and gene transcription. Heterochromatin protein 1(HP1) recognizes methylated H3K9 and reshapes the chromatin into the f HCs through liquid–liquid phase separation(LLPS). Among the three members of the HP1 family, HP1α can condensate by itself and HP1β forms granules with the help of TRIM28, while the HP1γ cannot phase separation alone either and the coordinator is still unclear. So, in this study, we investigated the molecular mechanism of how HP1γ interacts with TRIM66 through Px Vx L motif. Based on that, we examined the key regions that controlled the TRIM66-HP1γ co-phase separation behaviors both in vitro and in vivo. Furthermore, we proved that the liquid granules of TRIM66-HP1γ and chromatin highly correlated with H3K9me3 sites, which indicated the relationship with DNA damage response. Finally, combined with our previous study, we proposed the system for how TRIM66 remodeled the chromatin into compressed f HC through the TRIM66-HP1γ-H3K9me3 axis with liquid–liquid phase separation.

关键词： Chromatin TRIM66-HP1γ Facultative heterochromatin Phase separation

Turbulent drag reduction by sector-shaped counter-flow dielectric barrier discharge plasma actuator

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Chinese Physics B 2025年第2期34卷 362-370页

作者： Borui Zheng Shaojie Qi Minghao Yu Jianbo Zhang Linwu Wang Dongliang Bian School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an 710048China Science and Technology on Plasma dynamics laboratory Air Force Engineering UniversityXi’an 710038China Shaanxi Key laboratory of Complex System Control and Intelligent Information Processing Xi’an 710048China Shaanxi University Key laboratory of Photonic Power Devices and Discharge Regulation Xi’an 710048China

The primary objective in aircraft transportation is to minimize turbulent drag, thereby conserving energy and reducing emissions. We propose a sector-shaped counter-flow dielectric barrier discharge plasma actuator, which leverages jet synthesis for drag reduction. A drag control experiment was conducted in a low-speed wind tunnel with a controlled flow velocity of 9.6 m/s(Re = 1.445 × 10^(4)). This study investigated the effects of varying pulse frequencies and actuation voltages on the turbulent boundary layer. Using a hot-wire measurement system, we analyzed the pulsating and time-averaged velocity distributions within the boundary layer to evaluate the streamwise turbulent drag reduction. The results show that the local TDR decreases as the pulse frequency increases, reaching a maximum reduction of approximately 20.97% at a pulse frequency of 50 Hz. In addition, as the actuation voltage increases, the friction coefficient decreases, increasing the drag reduction rate. The maximum drag reduction of approximately 33.34% is achieved at an actuation voltage of 10 kV.

关键词： plasma flow control turbulent boundary layer turbulent drag reduction

Surface integrity characterization of thirdgeneration nickel-based single crystal blade tenons after ultrasonic vibration-assisted grinding

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Chinese Journal of Aeronautics 2025年第1期38卷 235-253页

作者： Biao ZHAO Hexu YOU Qing MIAO Wenfeng DING Ning QIAN Jiuhua XU national Key laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China

Machined surface integrity of workpieces in harsh environments has a remarkable influence on their ***,the complexity of the new type of machining hinders a comprehensive understanding of machined surface integrity and its formation mechanism,thereby limiting the study of component *** increasing demands for high-quality machined workpieces in aerospace industry applications,researchers from academia and industry are increasingly focusing on post-machining surface *** profile grinding test was conducted on a novel single-crystal superalloy to simulate the formation of blade tenons,and the obtained tenons were characterized for surface integrity elements under various operating *** revealed that ultrasonic vibration-assisted grinding(UVAG)led to multiple superpositions of abrasive grain trajectories,causing reduced surface roughness(an average reduction of approximately29.6%)compared with conventional *** examining the subsurface layer of UVAG using transmission electron microscopy,the results revealed that the single-crystal tenon grinding subsurface layer exhibited a gradient evolution from the near-surface to the *** evolution was characterized by an equiaxed nanocrystalline layer measuring 0.34μm,followed by a submicrocrystalline grain-forming zone spanning 0.6μm and finally,a constituent phase-twisted dis-torted deformation zone over 0.62μ*** normal grinding conditions,the tenon exhibited low surface hardening(not exceeding 15%),and residual compressive stresses were observed on its *** cases where grinding burns occurred,a white layer appeared on the tenon's surface,which demonstrated varying thicknesses along the teeth from top to root due to thermal-force-structural coupling ***,these burns introduced residual tensile stresses on the tenon's surface,potentially substantially affecting its fatigue *** paper enhances our understanding of UVAG pro

关键词： Single-crystal blade tenon Seeded gel abrasives Ultrasonic vibration-assisted profile grinding Surface integrity

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期68卷 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang QIN Xiao LUO Hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

关键词： graph representation learning graph neural networks graph contrastive learning graph augmentations graph pooling

Femtosecond mode-locking and soliton molecule generation based on a GaAs saturable absorber

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Chinese Physics B 2025年第1期34卷 344-349页

作者： Chen-Yan Zhang Xin-He Dou Zhen Chen Jing-Han Zhao Wei Sun Ze-Yu Fan Tao Zhang Hao Teng Zhi-Guo Lv School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Beijing national laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

In the last few years,research on advanced ultrafast photonic devices has attracted great interest from laser *** a semiconductor material with excellent nonlinear saturation absorption characteristics,Ga As has been used in solidstate and fiber lasers as a ***,the pulse widths that have been reported in the searchable published literature are all long and the shortest is tens of *** pulse widths,desired for a variety of applications,have not yet been reported in Ga As-based pulsed *** this work,we further explore the nonlinear characteristics of Ga As that has been magnetron sputtered onto the surface of a tapered fiber and its application in the generation of femtosecond lasing via effective dispersion optimization and nonlinearity *** the enhanced interaction between evanescent waves and Ga As nanosheets,mode-locked soliton pulses as short as 830 fs are generated at repetition rates of 4.64 *** far as we know,this is the first time that femtosecond-level pulses have been generated with a Ga As-based saturable *** addition,soliton molecules,including in the dual-pulse state,are also realized under stronger *** work demonstrates that Ga As-based photonic devices have good application prospects in effective polymorphous ultrashort pulsed laser generation.

关键词： GaAs saturable absorber mode-locking soliton molecule

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Biomimetic proton pocket and effective interfacial modulation for zinc metal anodes

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Science China Chemistry 2025年第2期68卷 526-535页

作者： Qi Dong Qingshun Nian Xuan Luo Jiajia Fan Jinyu Jiang Zhuangzhuang Cui Digen Ruan Xiaodi Ren Hefei national Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Rechargeable aqueous zinc batteries(RAZBs)offer a promising solution for large-scale energy storage due to the abundance,low cost,and safety of ***,practical applications are hindered by Zn anode instability,dendrite growth,and hydrogen evolution reactions(HER).Chaotropic Zn(ClO_(4))2 electrolytes are favorable for low-temperature operations but exacerbate these issues due to their high acidity,leading to severe Zn corrosion and layered double hydroxide *** propose a biomimetic strategy using methylguanidoacetic acid(creatine)as a low-cost,eco-friendly additive to address these *** acts as a proton pocket to finely tune the pH of acidic Zn(ClO_(4))2 electrolytes for suppressing HER and stabilizing the Zn ***,the formed creatinine cations adsorb on the Zn surface,promoting highly controlled Zn deposition with a preferred(002)*** approach significantly enhances battery cycling performance,with Zn||Zn cells demonstrating extended cycling stability at both low and high current ***||Cu cells exhibited improved Coulombic efficiency over thousands of cycles,indicating highly reversible Zn plating/***,stable cell operations were realized at the temperature as low as−35℃ without electrolyte *** findings highlight the potential of biomimetic proton regulation and interfacial modulation for improving the stability and reversibility of Zn plating/stripping in RAZBs.

关键词： zinc metal anode dendrite suppression interfacial modulation proton-triggered cyclization Zn(ClO_(4))2 electrolyte

Measurements of coupled fluid and sediment motion over mobile sand dunes in a laboratory flume

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International Journal of Sediment Research 2008年第4期23卷 329-337页

作者： Daniel G.WREN Roger A.KUHNLE Research Hydraulic Engineer USD A-ARS-National Sedimentation LaboratoryPh.D Research Hydraulic Engineer USD A-ARS-National Sedimentation Laboratory

The relationship between turbulent fluid motions and sediment particle motions over mobile sand dunes was investigated by using a laser Doppler velocimeter and an acoustic backscatter system in laboratory experiments performed at the usda-ars-national Sedimentation laboratory. Profiles of acoustic backscatter from particles and at-a-point turbulence data were collected while translating both measurement devices downstream at the speed of mobile dune bedforms. The resulting data set was used to examine the frequency (recurrence frequency) at which the fluctuating backscatter and fluid velocity signals exceeded magnitude thresholds based on the standard deviation (σ) of the local velocity and the magnitude the acoustic signal resulting from backscatter from suspended particles. The slope of the downstream and vertical velocity recurrence frequencies generally indicated a gradually increasing recurrence time with increasing elevation. The recurrence frequency for acoustic backscatter data was not strongly variable with elevation. The closest correspondence between the recurrence frequencies of sediment backscatter and vertical velocities at the 1σ magnitude threshold was in a region defined by X/L<0.4 and y<6 cm. The downstream velocity was most closely related to backscatter in a small region at 0.4

关键词： Turbulence Suspended sediment Acoustic backscatter Dunes

Influence of trains meeting on the ventilation performance of equipment compartment with independent air duct in high-speed train:numerical and experimental study

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Railway Engineering Science 2025年第1期33卷 127-150页

作者： Yitong Wu Wei Zhou Xifeng Liang Xinchao Su Kewei Xu Yutao Xia Zhixin Wang Sinisa Krajnović Key laboratory of Traffic Safety On Track Ministry of EducationSchool of Traffic and Transportation EngineeringCentral South UniversityChangsha 410075China Joint International Research laboratory of Key Technology for Rail Traffic Safety Central South UniversityChangsha 410075China Division of Fluid dynamics Department of Mechanics and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

During the train meeting events,train equipment compartments are exposed to the worst pressure changes,potentially affecting the ventilation performance of equipment,particularly for electrical facilities equipped with independent air *** this paper,a two-step method is used for numerical computation:(1)obtaining the temporal and spatial transient node data of the flow field sections during the train-passing simulation and(2)using the data as the input data for the equipment compartment *** addition,this paper also compares the difference in equipment ventilation between the single-train and trainpassing scenarios in real vehicle *** results indicate that the primary factors influencing ventilation effectiveness are the aerodynamic compression and deceleration of airflow induced by the other train's nose,as well as the instability of the external flow field in the wake of the other *** train crossing,the air is forced into the air duct,with a maximum ratio of the airflow in-duct to the airflow out-duct reaching *** average mass flow falls below the rated mass flow for the *** to the rated air volume of converter,the maximum suppression rates obtained from testing and simulation are-24.5%and-16.8%,*** to the single-train operation,the maximum suppression rates obtained from testing and simulation are-15%and-18%,*** findings provide valuable insights into the design and operation of high-speed trains.

关键词： Train-passing event Electrical facilities Independent air duct Ventilation performance

Solar-powered methanol synthesis from CO_(2) hydrogenation with high conversion and selectivity

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Science China Chemistry 2025年第2期68卷 513-519页

作者： Lingzhen Zeng Yongfang Sun Tingting Wang Zeyan Cen Maolin Wang Oriol Angurell Meng Wang Ding Ma Beijing national laboratory for Molecular Sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Leitat managing technologies Parc Cientific de BarcelonaEdifici Clúster ⅡPlanta 4Carrer Baldiri Reixac4-8.08028BarcelonaSpain

Methanol synthesis via CO_(2) hydrogenation stands as a pivotal avenue for CO_(2) conversion and fixation,garnering extensive *** reactor configurations and energy supplies,alongside a spectrum of catalyst formulations,have been developed to enhance reaction metrics including conversion,selectivity,productivity,and *** state-of-the-art Cu-based catalysts from thermal catalysis into a photothermal reactor yielded notable results,achieving an overall CO_(2) conversion of 98%and methanol selectivity of 86%.Utilizing the liquid out/gas in concept(LOGIC)reactor,in which only the catalyst bed is irradiated to raise its temperature,facilitated the condensation of products(H_(2)O and CH3OH),due to their low vapor *** lower concentration of products in vapor phases ensured the continuous progress of the *** synergistic integration of reactor design and catalyst fabrication could capitalize on the strengths of both components and lead to enhanced performance in methanol synthesis.

关键词： CO_(2) hydrogenation photothermal methanol synthesis