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An ensemble learning classifier to discover arsenene catalysts with implanted heteroatoms for hydrogen evolution reaction

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Journal of Energy Chemistry 2023年第3期78卷 268-276,I0008页

作者： An Chen Junfei Cai Zhilong Wang Yanqiang Han Simin Ye jinjin li Key Laboratory for Thin Film and Microfabrication of Ministry of Education Department of Micro/Nano-electronicsShanghai Jiao Tong UniversityShanghai 200240China

Accurate regulation of two-dimensional materials has become an effective strategy to develop a wide range of catalytic *** introduction of heterogeneous components has a significant impact on the performance of materials,which makes it difficult to discover and understand the structure-property relationships at the atomic ***,we developed a novel and efficient ensemble learning classifier with synthetic minority oversampling technique(SMOTE) to discover all possible arsenene catalysts with implanted heteroatoms for hydrogen evolution reaction(HER).A total of 850 doped arsenenes were collected as a database and 140 modified arsenene materials with different doping atoms and doping sites were identified as promising candidate catalysts for HER,with a machine learning prediction accuracy of 81%.Based on the results of machine learning,we proposed 13 low-cost and easily synthesized two-dimensional Fe-doped arsenene catalytic materials that are expected to contribute to high-efficient *** proposed ensemble method achieved high prediction accuracy,but millions of times faster to predict Gibbs free energies and only required a small amount of *** study indicates that the presented ensemble learning classifier is capable of screening high-efficient catalysts,and can be further extended to predict other two-dimensional catalysts with delicate regulation.

关键词： Ensemble learning Implanted heteroatoms Hydrogen evolution reaction Synthetic minority oversampling technique

Understory plant diversity and phenolic allelochemicals across a range of Eucalyptus grandis plantation ages

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林业研究:英文版 2023年第5期34卷 1577-1590页

作者： jinjin li Yumei Huang lianghua Chen Shun Gao Jian Zhang Danju Zhang Sichuan Provincial Key Laboratory of Ecological Forestry Engineering College of ForestrySichuan Agricultural UniversityWenjiang 611130ChengduChina College of Landscape Architecture Sichuan Agricultural UniversityWenjiang 611130ChengduChina

Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory *** compounds are the main allelochemicals suppressing understory ***,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely *** this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with *** phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere *** of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years *** concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in ***,phenolic compounds contributed more to the variation in the understory plants than soil *** acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation *** findings indicate that young *** plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential.

关键词： Eucalyptus grandis Phenolic compounds Understory plant diversity Plantation age

Two-dimensional molybdenum carbide(MXene)as an efficient nanoadditive for achieving superlubricity under ultrahigh pressure

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Friction 2023年第3期11卷 369-382页

作者： Shuang YI Yitong GUO jinjin li Yuxin ZHANG Aiguo ZHOU Jianbin LUO State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Henan Key Laboratory of Materials on Deep-Earth Engineering Henan Polytechnic University Jiaozuo 454003China

In this study,a robust macroscale liquid superlubricity with a coefficient of friction of 0.004 was achieved by introducing molybdenum carbide(Mo_(2)CT_(x))MXene nanoparticles as lubricating additives in a lithium hexafluorophosphate-based ionic liquid at Si_(3)N_(4)-sapphire *** maximal contact pressure in the superlubricity state could reach 1.42 GPa,which far exceeds the limit of the superlubricity regime in previous *** results indicate that a composite tribofilm(mainly containing molybdenum oxide and phosphorus oxide)that formed at the interface by a tribochemical reaction contributed to the excellent antiwear ***,the extremely low shear strength of the tribofilm and the interlayers of Mo_(2)CT_(x)MXene contributed to the *** work demonstrates the promising potential of Mo_(2)CT_(x)MXene in improving superlubricity properties,which could accelerate the application of superlubricity in mechanical systems.

关键词： molybdenum carbide(Mo_(2)CT_(x))MXene superlubricity additives ultrahigh pressure wear resistance

Hydrodynamic effect on the superlubricity of phosphoric acid between ceramic and sapphire

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Friction 2014年第2期2卷 173-181页

作者： Mingming DENG Chenhui ZHANG jinjin li liran MA Jianbin LUO State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China Shenzhen Key Laboratory of Micro-Nano Manufacturing Research Institute of Tsinghua University in ShenzhenShenzhen518057China

In this work,a super-low friction coefficient of 0.003 was found between a silicon nitride ball and a sapphire plate lubricated by phosphoric acid *** wear mainly occurred in the running-in period and disappeared after superlubricity was *** friction coefficient was effectively reduced from 0.3 to 0.003 at a constant speed of 0.076 m/s,accompanied by a 12-nm-thickness *** lubrication regime was indicated to change from boundary lubrication in the running-in period to elastohydrodynamic lubrication in the superlubricity period,which is also supported by the results of the friction coefficient versus sliding *** addition,the experimental results showed good agreement with theoretical calculations based on the elastohydrodynamic lubrication theory,suggesting a significant hydrodynamic effect of phosphoric acid on superlubricity.

关键词： liquid superlubricity phosphoric acid hydrodynamic lubrication film thickness

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邢台地区钻孔三维层序-构造可视化建模

华北地震科学 2024年第2期42卷 18-24页

作者：李姜孟立朋李津津李铁纯冯军河北省地震局石家庄050021 河北省地震动力学重点实验室河北三河065201 河北省建筑科学研究院有限公司石家庄050021 中国地震应急搜救中心北京100049

通过收集邢台地区已有的钻孔资料,结合浅层地震勘探成果、深部探测成果及部分石油物探资料,采用三维可视化Petrel建模软件,解决了建模中复杂地质现象的难题,精细地表达了研究区域的地质现象,建立了邢台地区第四系三维模型,详细分析了邢... 详细信息

通过收集邢台地区已有的钻孔资料,结合浅层地震勘探成果、深部探测成果及部分石油物探资料,采用三维可视化Petrel建模软件,解决了建模中复杂地质现象的难题,精细地表达了研究区域的地质现象,建立了邢台地区第四系三维模型,详细分析了邢台地区第四系分布特征。模拟结果显示:邢台地区的南部中央部位为一大型隆起区,直径达5km左右;区域内新近系和第四系为连续沉积,无明显分界线;地层整体上呈现东厚西薄的特征,在邢台东断裂的西部新近系较薄或基本缺失;Q1、Q2、Q3地层相对较厚,达到60~150m厚度,其地层南部的中央位置缺失,直径范围达3~5km左右;R地层主要分布在邢台东断裂以东的区域。

关键词：构造建模第四系分布特征地震危险性

Superlubricity of Si_3N_4 sliding against SiO_2 under linear contact conditions in phosphoric acid solutions

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Science China(Technological Sciences) 2013年第7期56卷 1678-1684页

作者： SUN liang ZHANG ChenHui li jinjin liU YuHong LUO JianBin State Key Laboratory of Tribology Tsinghua University Shenzhen Key Lab of Micro-nano Manufacturing Research Institute of Tsinghua University in Shenzhen

Superlubricity phenomena, which were previously achieved merely under point contact conditions, have been observed under the linear contact condition between the silicon nitride (Si3N4) cylinder and the silica (SiO2) ring in phosphoric acid *** a total 800 s running-in period and low friction stage, the friction coefficient finally declined to about 0.003. The ultralow friction coefficient could last for more than 5 h. In these experiments, a torque sensor of high accuracy was used to make sure that the measuring result was credible. The differences between superlubricity experiments in our group and others were dis-cussed. Unlike the situations in other superlubricity experiments about silicon nitride, where the specimens were immersed in water totally, the phosphoric acid solution with volume of only 150 μL was used in these tests. It was proved that free water in the solution had a great relationship to the necessary time of acquiring superlubricity and phosphoric acid played a unique role in the superlubricity, which could not be explained properly by the hydrodynamic lubrication model proposed by others. Fi-nally, based on the results of the friction tests and the analysis with scanning electron microscope (SEM), a modified hydro-gen-bonded network and hydrated shearing layer model was proposed to explain the mechanism of superlubricity.

关键词： superlubricity ceramics phosphoric acid linear contact

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FT-粗糙集模型的一些性质

泉州师范学院学报 2024年第2期42卷 1-9页

作者：张纪平周缪娟李进金泉州师范学院数学与计算机科学学院福建泉州362000 闽南师范大学数学与统计学院福建漳州363000

T-粗糙集是Pawlak粗糙集理论发展过程中的一个重要模型,已成功应用于数据挖掘等诸多领域.FT-粗糙集模型能够在保持数据的完整性下处理连续型数据,是对仅能处理离散型数据的T-粗糙集模型上的发展.文章引入模糊近似空间(X,Y,T)一对模糊集... 详细信息

T-粗糙集是Pawlak粗糙集理论发展过程中的一个重要模型,已成功应用于数据挖掘等诸多领域.FT-粗糙集模型能够在保持数据的完整性下处理连续型数据,是对仅能处理离散型数据的T-粗糙集模型上的发展.文章引入模糊近似空间(X,Y,T)一对模糊集的弱逆和强逆定义,用量化方法研究FT-粗糙集的一些性质,得到模糊技能映射在析取模型、合取模型下分别生成的知识结构;用量化方法与矩阵表示探究FT-粗糙集模糊集值映射在并、交运算下的性质.

关键词： FT-粗糙集模糊近似空间下逆和上逆弱逆和强逆

腹股沟疝修补术后慢性疼痛风险预测模型的构建及验证

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中华现代护理杂志 2024年第21期30卷 2910-2915页

作者：韩玲张茜王玲玲李进瑾新乡市中心医院(新乡市第四临床学院)普通外科新乡453000

目的调查腹股沟疝患者疝修补术后慢性疼痛发生情况,分析疼痛发生的风险因素并建立列线图模型。方法采用便利抽样法,选取2021年6月—2022年12月在新乡市中心医院行腹股沟疝修补术的患者390例,根据是否发生术后慢性疼痛分为慢性疼痛组和... 详细信息

目的调查腹股沟疝患者疝修补术后慢性疼痛发生情况,分析疼痛发生的风险因素并建立列线图模型。方法采用便利抽样法,选取2021年6月—2022年12月在新乡市中心医院行腹股沟疝修补术的患者390例,根据是否发生术后慢性疼痛分为慢性疼痛组和非慢性疼痛组。应用Logistic回归分析术后慢性疼痛的危险因素,采用R4.2.3软件包和rms程序包建立列线图模型。结果390例腹股沟疝患者发生术后慢性疼痛73例,发生率为18.72%。Logistic回归分析显示,再次腹股沟疝手术、疝环缺损直径≤37.5px、嵌顿、使用修补材料和术后切口感染为发生慢性疼痛的危险因素(P<0.05)。基于以上因素建立风险预测模型,受试者工作曲线下面积为0.751(95%置信区间:0.612~0.753),Hosmer-Lemeshow检验结果显示χ^(2)=5.572,P=0.473,校正曲线趋近于理想曲线。结论腹股沟疝患者术后慢性疼痛发生较普遍,存在多个危险因素;本研究建立的列线图模型能够在一定程度上为制订护理策略提供依据。

关键词：腹股沟疝疝修补术慢性疼痛列线图预测模型危险因素

Oriented magnetic liquid metal-filled interlocked bilayer films as multifunctional smart electromagnetic devices

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Nano Research 2023年第1期16卷 1764-1772页

作者： jinjin li Yue Zhang Xufeng li Chunyan Chen Haihan Zou Peng Yi Xiaofang liu Ronghai Yu School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Smart electromagnetic functional devices prepared based on electromagnetic wave responsive materials will provide more convenience for human life in the ***,we prepare oriented magnetic liquid metal droplet-filled polydimethylsiloxane films with micropillar array patterned surfaces,and further assemble them into bilayer films with interlocked *** compressed,the increase in conductivity of the film due to the tunneling effect between microarrays and the elongation of liquid metal droplets leads to a rapid increase in electromagnetic interference shielding ***,a tunable electromagnetic interference shielding material with high sensitivity and wide control range is obtained,which has potential applications in electromagnetic wave control systems and intelligent electromagnetic protection ***,we assemble a strain sensor and a magnetic sensor,which can precisely sense pressure and magnetic field according to changes in electromagnetic signal and electrical signal,respectively.

关键词： magnetic liquid metal electromagnetic interference shielding interlocked structure electromagnetic sensing magnetic sensing