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Mechanical properties of hot-pressed high-entropy diboride-based ceramics

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Journal of Advanced Ceramics 2020年第4期9卷 503-510页

作者： Ji-Xuan Liu xiao-qin shen Yue Wu Fei Li Yongcheng Liang Guo-Jun Zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringCollege of SciencesInstitute of Functional MaterialsDonghua UniversityShanghai201620China

High-entropy ceramics attract more and more attention in recent ***,mechanical properties especially strength and fracture toughness for high-entropy ceramics and their composites have not been comprehensively *** this work,high-entropy(Ti0.2Zr0.2Hf0.2Nb0.2Ta 0.2)B2(HEB)monolithic and its composite containing 20 vol%SiC(HEB–20SiC)are prepared by hot *** addition of SiC not only accelerates the densification process but also refines the microstructure of HEB,resulting in improved mechanical *** obtained dense HEB and HEB–20SiC ceramics hot pressed at 1800℃exhibit four-point flexural strength of 339±17 MPa and 447±45 MPa,and fracture toughness of 3.81±0.40 MPa·m1/2 and 4.85±0.33 MPa·m1/2 measured by single-edge notched beam(SENB)*** deflection and branching by SiC particles is considered to be the main toughening mechanisms for the HEB–20SiC *** hardness Hv0.2 of the sintered HEB and HEB–20SiC ceramics is 23.7±0.7 GPa and 24.8±1.2 GPa,*** the increase of indentation load,the hardness of the sintered ceramics decreases rapidly until the load reaches about 49 N,due to the indentation size *** on the current experimental investigation it can be seen that the room temperature bending strength and fracture toughness of the high-entropy diboride ceramics are within ranges commonly observed in structure ceramics.

关键词： high-entropy ceramics high-entropy diboride flexural strength fracture toughness indentation size effect

Characterization of petrophysical and seismic properties for CO2 storage with sensitivity analysis

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Petroleum Science 2025年第1期22卷 193-209页

作者： Yan-Jiao Dong Yi shen Kai Guo xiao-qin Wu Qiang Mao Wen-Yue Sun Zhi-Qiang Wang State Key Laboratory of Offshore Oil and Gas Exploitation Geosciences Department China University of Petroleum (East China) CNOOC Research Institute Ltd. School of Petroleum Engineering China University of Petroleum (East China)

Saline aquifers are considered as highly favored reservoirs for CO2sequestration due to their favorable properties. Understanding the impact of saline aquifer properties on the migration and distribution of CO2plume is crucial. This study focuses on four key parameters—permeability, porosity, formation pressure, and temperature—to characterize the reservoir and analyse the petrophysical and elastic response of CO2. First, we performed reservoir simulations to simulate CO2saturation, using multiple sets of these four parameters to examine their significance on CO2saturation and the plume migration ***, the effect of these parameters on the elastic properties is tested using rock physics *** established a relationship of compressional wave velocity（Vp） and quality factor（Qp） with the four key parameters, and conducted a sensitivity analysis to test their sensitivity to Vpand Qp. Finally, we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed Vpand Qpmodels, and analysed the impact of CO2saturation changes on seismic data. As for the above numerical simulations and analysis, we conducted sensitivity analysis using both homogeneous and heterogeneous models. Consistent results are found between homogeneous and heterogeneous models. The permeability is the most sensitive parameter to the CO2saturation, while porosity emerges as the primary factor affecting both Qpand Vp. Both Qpand Vpincrease with the porosity, which contradicts the observations in gas reservoirs. The seismic simulations highlight significant variations in the seismic response to different parameters. We provided analysis for these observations, which serves as a valuable reference for comprehensive CO2integrity analysis, time-lapse monitoring, injection planning and site selection.

关键词： CO2 storage Time-lapse seismic CO2 plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer

Loosening metal nodes in metal-organic frameworks to facilitate the regulation of valence

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Fundamental Research 2025年第1期5卷 158-164页

作者： Li, Yu-Xia shen, Jia-Xin Diao, Ze-Jiu Qi, Shi-Chao Liu, xiao-qin Sun, Lin-Bing State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) College of Chemical Engineering Nanjing Tech University Nanjing 210009 China

The valence of metal nodes in metal-organic frameworks (MOFs) determines their performance in applications while developing an efficient approach for valence regulation is challenging. Here we present a strategy to make the valence regulation much easier by loosening metal nodes by thermal pretreatment. The typical MOF, HKUST-1, with the tunable valence of Cu nodes, was used as a proof of concept. Thermal pretreatment (producing HK-T) changes the chemical environment and loosens Cu nodes, endowing them with enhanced reducibility. In the subsequent vapor-induced reduction, the yield of Cu+ from Cu2+ conversion in HK-T (producing HK-T-V) reaches 69%, which is higher than that in pristine HKUST-1 (producing HK-V) with a Cu+ yield of 19% as well as the reported yields of target-valence metal nodes in various MOFs (6∼30%). The obtained HK-T-V possessing abundant Cu+ sites can capture 0.809 mmol/g thiophene in adsorptive desulfurization, 2.5 times higher than HK-V and superior to most reported adsorbents. © 2022

关键词： Adsorption Copper Desulfurization Metal-organic frameworks Valence regulation

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二水平正交饱和设计中零效应搜索法的推广

山西大学学报(自然科学版) 2010年第2期33卷 182-185页

作者：张晓琴赵深淼山西大学数学科学学院

文[5]中提出的零效应搜索法是分析饱和设计的有效方法.一般假定误差是服从正态分布的.零效应搜索法对于密度函数是对称分布的函数也适用,因此零效应搜索法对t分布也适用.由于t分布的密度函数比较复杂,无法给出统计量的具体形式,但可通... 详细信息

文[5]中提出的零效应搜索法是分析饱和设计的有效方法.一般假定误差是服从正态分布的.零效应搜索法对于密度函数是对称分布的函数也适用,因此零效应搜索法对t分布也适用.由于t分布的密度函数比较复杂,无法给出统计量的具体形式,但可通过模拟来实现,通过对各种情况的模拟计算来说明零效应搜索法对t分布也适用.本文选择自由度为3的t分布做模拟.并且在此假定下,也能很好的识别饱和设计中的显著因子,误差方差的估计也很好.

关键词：正交饱和设计次序统计量零效应搜索法显著效应 t分布

Targeted sounding observations from geostationary satellite and impacts on high impact weather forecasts

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Science China Earth Sciences 2025年

作者： Wei HAN Ruoying YIN Jun LI Yongzhu LIU Jincheng WANG Yonghui LI xiaohao qin Zhiqing ZHANG Xueshun shen CMA Earth System Modeling and Prediction Centre (CEMC) State Key Laboratory of Severe Weather (LaSW) National Satellite Meteorological Center State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

In monitoring and predicting high-impact weather(HIW) events, targeted atmospheric temperature and moisture sounding observations in sensitive areas are more valuable than conventional observations. The conditional nonlinear optimal perturbation(CNOP) method and the linear singular vector(SV) method can be employed to identify these weather-sensitive areas for targeted observations. Such observations can be conducted by using hyperspectral infrared sounders onboard geostationary weather satellites. The Geostationary Interferometric Infrared Sounder(GIIRS) onboard China's Fengyun(FY)-4geostationary satellite series can provide atmospheric sounding observations with a temporal resolution of up to 15 min over areas prone to active weather events. GIIRS offers unprecedented opportunities for targeted observations, enabling flexible measurement modes that focus on weather-sensitive areas. High-temporal-resolution measurements not only reveal the threedimensional(3D) thermodynamic structure of the atmosphere, but also track moisture characteristics to capture the 3D dynamic structure. Moreover, high-temporal-resolution measurements of clear radiances can enhance atmospheric sounding retrievals(used for HIW situation awareness) and data assimilation(used to improve numerical weather prediction). The four-dimensional variational(4D-Var) system facilitates the utilization of the high-temporal-resolution GIIRS targeted observations. In this study,we explore the applications of FY-4A and FY-4B GIIRS targeted observations and focus on data assimilation based on the 4DVar system for improving HIW forecasts. Several typhoon cases are selected for impact analysis. Moreover, we compare CNOP and SV methods for identifying sensitive areas, and use the 4D-Var assimilation system of the Global Assimilation Forecasting System of the China Meteorological Administration(CMA-GFS) for real-time data assimilation. The results indicate hightemporal-resolution observations positively impact ty

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基于改进Res2Net与迁移学习的水果图像分类

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电子科技大学学报 2025年第1期54卷 62-71页

作者：吴迪肖衍沈学军万琴陈子涵湖南工程学院电气与信息工程学院湘潭411100 湖南大学机器人视觉感知与控制技术国家工程研究中心长沙410082

针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成... 详细信息

针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成卷积核,利用meta-ACON激活函数优化ReLU激活函数,动态学习激活函数的线性和非线性,自适应选择是否激活神经元;其次,采用基于模型迁移的训练方式进一步提升分类的效率与鲁棒性。实验结果表明,该算法在Fruit-Dataset和Fruits-360数据集上的测试准确率相比Res2Net提升了1.2%和1.0%,召回率相比Res2Net提升了1.13%和0.89%,有效提升了水果图像分类性能。

关键词：图像分类 Res2Net 动态多尺度融合注意力激活函数迁移学习

Low-carbon Economic Energy Routing Strategy via Adaptive Geometry Estimation Based Multi-objective Evolutionary Algorithm

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Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering 2025年第4期45卷 1394-1408页

作者： Hua, Haochen Shi, Junbo Chen, Xingying Yu, Kun qin, Yuchao shen, Jun Ding, Yi He, Dawei College of Energy and Electrical Engineering Hohai University Jiangsu Province Nanjing210098 China Department of Applied Mathematics and Theoretical Physics University of Cambridge CambridgeCB3 0WA United Kingdom School of Mechanical Engineering Beijing Institute of Technology Haidian District Beijing100081 China College of Electrical Engineering Zhejiang University Zhejiang Province Hangzhou310027 China Sichuan Energy Internet Research Institute Tsinghua University Sichuan Province Chengdu610213 China

With the continuous promotion of the "Carbon peak and carbon neutrality", the regional energy internet based on energy router has received widespread attention. This article aims to study an energy routing strategy, which enables the system to operate in a low-carbon and economically efficient manner by selecting the optimal energy routing path. It should be emphasized that in the graph structured regional energy internet, the energy routing path with the least power loss may not necessarily lead to the lowest carbon emissions, and vice versa. In order to simultaneously reduce the power losses and carbon emissions in the system, this paper proposes an energy routing strategy to achieve Pareto optimality between power losses and carbon emissions by controlling the output of each microgrid and selecting the energy supply path. First, this article proposes a congestion free path search method based on depth-first search to obtain energy routing path. Afterwards, adaptive geometry estimation based multi-objective evolutionary algorithm (AGE-MOEA) is used to quickly obtain the Pareto optimal set. Then, the optimal compromise solution can be selected through the comprehensive weight-technique for order preference by similarity to an ideal solution (TOPSIS). Finally, simulation analysis is conducted in the regional energy internet scenario, and the results show that compared with the existing energy routing algorithm, the energy routing strategy proposed in this paper can reduce carbon emissions by 58.24% with only a 4.73% increase in power losses. Moreover, the AGE-MOEA used in this paper reduces the solution time by 5.8% compared to the existing algorithm while guaranteeing the effectiveness of the solution. ©2025 *** ***.

关键词： Evolutionary algorithms

基于液相色谱-质谱代谢组学技术的硒化黑木耳代谢产物及通路分析

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食品科学 2025年第3期46卷 162-168页

作者：岳诗博崔航沈琴曹冬梅黑龙江八一农垦大学食品学院黑龙江大庆163319 黑龙江八一农垦大学牡丹江食品与生物技术创新研究院黑龙江牡丹江157000 国家杂粮工程技术研究中心黑龙江大庆163319 潍坊食品科技职业学院山东潍坊262123 黑龙江省农产品加工与质量安全重点实验室黑龙江大庆163319 黑龙江省杂粮加工及质量安全工程技术研究中心黑龙江大庆163319

本研究通过在黑木耳菌包中添加外源硒,结合液相色谱-质谱联用代谢组学技术,运用主成分分析、偏最小二乘判别分析、层次聚类分析等多元统计学分析,探究硒化对黑木耳代谢通路及代谢物的动态变化影响。结果表明,从黑木耳(HME)、亚硒酸钠无... 详细信息

本研究通过在黑木耳菌包中添加外源硒,结合液相色谱-质谱联用代谢组学技术,运用主成分分析、偏最小二乘判别分析、层次聚类分析等多元统计学分析,探究硒化对黑木耳代谢通路及代谢物的动态变化影响。结果表明,从黑木耳(HME)、亚硒酸钠无机硒化黑木耳(HMEa)和富硒玉米秸秆有机硒化黑木耳(HMEb)组共定性出669个代谢物,通过对差异代谢物进行筛选,无机硒化组(HME vs HMEa)共得到228个差异代谢物;有机硒化组(HME vs HMEb)共得到267个差异代谢物,硒化对黑木耳中有机酸及其衍生物、脂类及类脂质分子含量影响较大,且有机硒化富硒效果更显著。综合两组的京都基因与基因组百科全书代谢通路分析,发现硒化对脂类代谢、氨基酸类代谢影响显著。综上所述,黑木耳受到硒化后,脂类代谢、氨基酸代谢以及其他次生代谢产物的生物合成过程发生显著变化,对黑木耳中脂类和氨基酸等代谢产物产生显著影响,说明硒化会对黑木耳的营养成分和风味品质产生一定影响。

关键词：硒化黑木耳液相色谱-质谱法非靶向代谢组学

Proteomic Analysis of Physcomitrella patens under Cold Stress

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Proteomic Analysis of Physcomitrella patens under Cold Stres...