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Science China(Information Sciences) 2025年第1期68卷 400-401页

作者： Chenyu liU Yibo WANG Wenhui XU Shuqi HUANG Chunxiao YU Zeyu yang Xiaole JIA Xiaoxi li Bochang li Zhengdong LUO Cizhe FANG Yan liU Tiangui YOU Xin OU Genquan HAN School of Microelectronics Xidian University Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Hangzhou Institute of Technology Xidian University

Titanium/Gold （Ti/Au） metals have been widely employed as ohmic metal contacts on n+Ga2O3,exhibiting the specific contact resistance （ρc） of 10-5-10-6Ω·cm2[1].But previous studies have revealed the presence of a defective Ga2O3layer and reactive Ti-Ga2O3layer at the annealed Ti/*** an interfacial layer can afect the performance of ohmic contact,which may become more pronounced in power devices subjected to electrical stress and high-frequency ***,there have been no reports on the impact of bias stress effects and dynamic degradation of Ti/Au ohmic contacts on n+Ga2O3.

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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape

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Journal of Energy Chemistry 2025年第1期100卷 201-214页

作者： Xuewei Zhang Wei Zhou Yuming Huang liang Xie Tonghui li Huimin Kang lijie Wang yang Yu Yani Ding Junfeng li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao School of Energy Science and Engineering Harbin Institute of Technology China Datang Technology Innovation Co. Ltd

The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis （PEMWE） emerging as the preeminent pathway for hydrogen *** remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable *** impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles *** address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis *** to constant voltage electrolysis (hydrogen production rate:51.6 m L h-1,energy consumption:5.37 kWh Nm-3H2),this strategy (hydrogen production rate:66 m L h-1,energy consumption:3.83 kWh Nm-3H2) increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic （PV） system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 *** combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis （PDE） dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode *** such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport *** promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors.

关键词： Electrolysis

农业触土机具材料表面涂层减阻抗磨特性研究进展

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材料热处理学报 2024年第11期45卷 24-36页

作者：李祖阳陈文刚张垚代炳贵张继豪杨晓东杨加威西南林业大学机械与交通学院云南昆明650224 云南省Dongyang li院士工作站云南昆明650224

农业触土机具表面的减阻性能和耐磨特性决定了其自身的工作寿命和能耗,通过表面改性技术在触土机具表面制备高硬耐磨涂层可以有效地提高触土机具的减阻抗磨性能,降低农业机械能源消耗。本文介绍了农业触土部件的磨损因素及触土机具的表... 详细信息

农业触土机具表面的减阻性能和耐磨特性决定了其自身的工作寿命和能耗,通过表面改性技术在触土机具表面制备高硬耐磨涂层可以有效地提高触土机具的减阻抗磨性能,降低农业机械能源消耗。本文介绍了农业触土部件的磨损因素及触土机具的表面磨损机理,从不同表面改性技术的角度总结了农业触土机具常用材料表面涂层减阻抗磨的研究进展,对复合材料改性涂层缺陷的研究成果进行了归纳,并对农业触土机具材料表面涂层的未来发展进行了展望。

关键词：触土机具涂层技术减阻抗磨热处理

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Lenalidomide regulates the CCL21/CCR7/ERK1/2 axis to inhibit migration and proliferation in diffuse large B-cell lymphoma

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Oncology Research 2025年第1期33卷 199-212页

作者： WEN yang BIN TANG DAN XU WENXIU yang Department of Pathology Guizhou Medical UniversityThe Affiliated Hospital of Guizhou Medical UniversityGuiyang550004China

Background:The prognostic significance of the chemokine receptor CCR7 in diffuse large B-cell lymphoma(DLBCL)has been reported ***,the detailed mechanisms of CCR7 in DLBCL,particularly regarding its interaction with lenalidomide treatment,are not fully ***:Our study utilized bioinformatics approaches to identify hub genes in SU-DHL-2 cell lines treated with lenalidomide compared to control *** data and clinical information from 122 patients with DLBCL were analyzed to assess the correlation of CCR7 and p-ERK1/2 expression with the prognosis of ***,in vitro and in vivo experiments were conducted to clarify the role of CCR7 in the response of DLBCL to lenalidomide ***:Our bioinformatics analysis pinpointed CCR7 as a hub gene in the context of lenalidomide treatment in ***,31.14%and 36.0%(44/122)of DLBCL cases showed positive expression for CCR7 and ERK1/2 respectively,establishing them as independent prognostic factors for adverse outcomes in DLBCL via multivariate Cox regression ***,our studies demonstrated that the external application of the protein CCL21 promoted proliferation,migration,invasion,and activation of the ERK1/2 pathway in SU-DHL-2 and OCI-LY3 cell lines with high levels of CCR7 *** effect was mitigated by CCR7 silencing through siRNA,application of ERK inhibitors,or lenalidomide *** vivo experiments reinforced the efficacy of lenalidomide,significantly reducing tumor growth rate,tumor mass,serum total LDH levels,and expression of CCR7 and p-ERK1/2 in a SUDHL-2 xenograft model in nude mice(plidomide in DLBCL treatment.

关键词： CCR7 CCL21 ERK1/2 Lenalidomide Diffuse large B-cell lymphoma(DLBCL)

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng yang Hai-Feng Song Jin-Shan li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng HE Fan yang Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang li-Shuo Zheng Yu-Tao Zheng Yi-Wei Dong liping Huang Xiaoping Wang Wei Jiang liu-Pan yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

Substrate bias effects in p-channel GaN-on-Si transistors

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Science China(Information Sciences) 2025年第1期68卷 404-405页

作者： Mengyao ZHAO Jie MA Lanlan yang Chuanqi PAN Denggui WANG Jianjun ZHOU Sheng li Jiaxing WEI Long ZHANG Siyang liU Weifeng SUN National ASIC System Engineering Research Center School of Integrated Circuits Southeast University National Center of Technology Innovation for Electronic Design Automation Southeast University National Key Laboratory of Solid-State Microwave Devices and Circuits

The drain current （ID） of the n-channel GaN field-effecttransistor （n-FET） is influenced by the substrate-to-source bias voltage (VBS)（substrate bias effect）[1].Actually,nonzero VBSis also likely to occur in p-FET in real application,because the source electrode of p-FET is usually connected to high *** study reports the dependency between IDand VBSin p-FET for the first time,and analyzes the underlying mechanisms from the perspective of vertical electric field （EF） distribution.

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Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing HAO Jin-Hui yang Guang ZHU State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong li li Dan Jing Peng Qidong yang Fuqiang yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

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