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China Foundry 2024年第6期21卷 685-692页

作者： Ji-peng li De-gao Qiao Jian li Peng Peng Kai-di Hu Xian-tao Yan Shu-sen cheng Yuan-li Xu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735100GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China

In this study,directional solidification was utilized to explore the relationship between microstructure,mechanical properties,and withdrawal speeds of Zn-55Al-1.6Si *** order to assess the characteristics of Zn-55Al-1.6Si alloys,both the microstructure and mechanical properties were thoroughly *** involved conducting room temperature tensile tests on samples with different withdrawal speeds(5,10,100,200,and 400μm·s^(-1)).The results reveal that both the as-cast alloy and samples after directional solidification are composed of zinc,aluminum,and silicon *** the withdrawal speed increases,an evident decrease in the size of the primary dendrites is *** results of tensile experiments show that Zn-55Al-1.6Si alloys after directional solidification exhibit brittle fracture characteristics,both the tensile strength and elongation of the alloys increase with withdrawal speed.

关键词： Zn-55Al-1.6Si alloy directional solidification microstructure mechanical properties

Alkali ion-promoted palladium subnanoclusters stabilized on porous alumina nanosheets with enhanced catalytic activity for benzene oxidation

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Nano Research 2022年第7期15卷 5912-5921页

作者： Zhijun li Minghui di Wei Wei Leipeng Leng Zhijun li cheng He Qiang Tan Qian Xu J.Hugh Horton li li Junfa Zhu Joint International Research Laboratory of Advanced Chemical Catalytic Materials&Surface Science College of Chemistry and Chemical EngineeringNortheast Petroleum UniversityDaqing 163318China Key Laboratory of Functional Inorganic Materials Chemistry(Ministry of Education) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China State Key Laboratory for Mechanical Behavior of Materials School of Material Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Department of Chemistry Queen’s UniversityKingston K7L 3N6Canada College of Chemistry and Chemical Engineering Qiqihar UniversityQiqihar 161006China

Catalytic C−H bond activation is one of the backbones of the chemical *** metal subnanoclusters consisting of a few atoms have shown attractive properties for heterogeneous ***,the creation of such catalyst systems with high activity and excellent anti-sintering ability remains a grand ***,we report on alkali ion-promoted Pd subnanoclusters supported over defectiveγ-Al_(2)O_(3) nanosheets,which display exceptional catalytic activity for C−H bond activation in the benzene oxidation *** presence of Pd subnanoclusters is verified by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy,X-ray absorption spectroscopy,and X-ray photoelectron *** catalyst shows excellent catalytic activity,with a turnover frequency of 280 h^(−1) and yield of 98%,in benzene oxidation reaction to give phenol under mild ***,the introduction of alkali ion greatly retards the diffusion and migration of metal atoms when tested under high-temperature sintering *** functional theory(DFT)calculations reveal that the addition of alkali ion to Pd nanoclusters can significantly impact the catalyst’s structure and electronic properties,and eventually promote its activity and *** work sheds light on the facile and scalable synthesis of highly active and stable catalyst systems with alkali additives for industrially important reactions.

关键词： Pd subnanoclusters γ-Al_(2)O_(3)nanosheets heterogeneous catalysis benzene oxidation catalytic activity

Gradient wettability induced by deterministically patterned nanostructures

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Microsystems & Nanoengineering 2020年第1期6卷 136-144页

作者： Siyi Min Shijie li Zhouyang Zhu Wei li Xin Tang Chuwei liang liqiu Wang Xing cheng Wen-di li Department of Mechanical Engineering The University of Hong KongHong Kong 999077China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518052China HKU-Zhejiang Institute of Research and Innovation(HKU-ZIRI) Hangzhou 311305 ZhejiangChina

We report a large-scale surface with continuously varying wettability induced by ordered gradient *** gradient pattern is generated from nonuniform interference lithography by utilizing the Gaussian-shaped intensity distribution of two coherent laser *** also develop a facile fabrication method to directly transfer a photoresist pattern into an ultraviolet(UV)-cured high-strength replication molding material,which eliminates the need for high-cost reactive ion etching and e-beam evaporation during the mold fabrication *** facile mold is then used for the reproducible production of surfaces with gradient wettability using thermal-nanoimprint lithography(NIL).In addition,the wetting behavior of water droplets on the surface with the gradient nanostructures and therefore gradient wettability is investigated.A hybrid wetting model is proposed and theoretically captures the contact angle measurement results,shedding light on the wetting behavior of a liquid on structures patterned at the nanoscale.

关键词： gradient pattern utilizing

Effect of micro-alloying Ca on microstructure,texture and mechanical properties of Mg-Zn-Y-Ce alloys

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Progress in Natural Science:Materials International 2020年第2期30卷 213-220页

作者： Xiaofang liu Xianhua Chen Jianbo li Chunquan liu di Zhao Renju cheng Fusheng Pan International Joint Laboratory for light Alloys(MOE) College of Materials Science and EngineeringChongqing University National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing Academy of Science and Technology Shenyang Notional Laboratory for Materials Science Chongqing University

Microstructure,texture and mechanical properties of Mg-5 Zn-0.3 Y-0.2 Ce alloys with the addition of trace xCa(x=0,0.3,0.6 wt%) were systematically investigated in this *** results revealed that more secondary eutectic phases and smaller grain size of as-cast microstructure could be found with increasing Ca *** hot extrusion,the Ca-free alloy showed a uniformly recrystallized grain structure,while the Ca-containing alloys possessed a bimodal grain structure composed of fine dynamic recrystallized(DRXed) grains with a size of several microns and un-recrystallized coarse *** analysis showed that the three extruded alloys had a fiber texture of(0001) basal plane aligned with the extrusion *** intensity of the DRXed region was weaker than the deformed *** extruded alloy with the addition of 0.6 wt% Ca exhibited the highest yield strength of 321 MPa due to the smallest DRXed grain size,the deformed region with strong basal texture and dense nanosized precipitates.

关键词： Ca micro-alloying Extrusion Microstructure Texture Mechanical properties Mg–Zn–Y–Ce alloy

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制造业数字化转型与绿色技术创新的关系研究

工业技术经济 2025年第1期44卷 115-121页

作者：成新轩丰义李明峰河北大学经济学院保定071002 河北经贸大学工商管理学院石家庄050000

为深入探究数字化转型与制造业绿色技术创新之间的关系,本文以2013~2023年全国制造业为研究对象,开展制造业数字化转型与绿色技术创新的关系实证研究。以制造业绿色技术创新效率为因变量,以制造业数字化转型水平为自变量,以行业规模、... 详细信息

为深入探究数字化转型与制造业绿色技术创新之间的关系,本文以2013~2023年全国制造业为研究对象,开展制造业数字化转型与绿色技术创新的关系实证研究。以制造业绿色技术创新效率为因变量,以制造业数字化转型水平为自变量,以行业规模、资本强度、融资能力、外资投入比、技术成熟度为控制变量,通过回归分析、稳健性、异质性检验等,验证因变量与自变量之间的关系。结果表明:数字化转型显著促进了制造业绿色技术创新,且行业规模越大和资本强度越强的制造业,其绿色技术创新效率越高;数字化转型对出口依赖度、发展阶段、数字化来源、行业要素不同的制造业促进效果不同,对出口依赖度高、发展阶段靠前、国际数字化来源和高技术创新的制造业绿色技术创新促进作用更强;数字化转型可通过减少外部交易成本和提高市场竞争的方式,促进制造业绿色技术的创新。为提高制造业绿色技术创新,本文提出包含加强行业市场竞争力和加强政府监管等策略,以期能够更好地发挥数字化转型对制造业绿色技术创新的促进作用。

关键词：数字化制造业技术创新效率稳健性异质性行业市场竞争力政府监管

A new understanding of the effect of Cr on the corrosion resistance evolution of weathering steel based on big data technology

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Journal of Materials Science & Technology 2022年第9期104卷 67-80页

作者： Xiaojia Yang Ying Yang Meihui Sun Jinghuan Jia Xuequn cheng Zibo Pei Qing li di Xu Kui Xiao Xiaogang li Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399China State Key Laboratory of Metal Material for Marine Equipment and Application AnsteelAnshan 114021China

In this work,we studied the effect of Cr element on the corrosion resistance evolution of weathering steel based on corrosion big data *** suggested that corrosion big data technology is suitable for evaluation of the effect of microalloying Cr element on the corrosion evolution behavior of weathering *** understandings prove that the effect of Cr on the corrosion process is dynamic rather than static,the processes is affected by both of the environmental factors and the electrochemical or chemical reactions in the rust ***,Cr element has both beneficial effect and detrimental effect on the corrosion resistance of weathering *** beneficial effect is that the general corrosion resistance of Cr-additional steel is better than that of Cr-free steel,while the detrimental effect is that localized corrosion is intensified as the increase of Cr content in the Cr-additional steel.

关键词： Weathering steel Cr-addition Big data Atmospheric corrosion

Experimental study on the penetration effect of ceramics composite projectile on ceramic/A3 steel compound targets

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Defence Technology（防务技术） 2017年第4期13卷 281-287页

作者： di-qi Hu Jian-ru Wang li-kui Yin Zhi-gang Chen Rong-cheng Yi cheng-hua Lu National Defense Key Laboratory of Underground Damage Technology North University of China Taiyuan 030051 China Changzhou Sanyou Sissan Protective Materials MFG Co. Ltd Changzhou 213100 China

In order to improve the penetration of projectiles into ceramic composite armors,the nose of 30 mm standard projectile was replaced by a toughened ceramic nose,and the performance of ceramic-nose projectiles penetrating into ceramic/A3 steel composite targets has been experimentally *** to impact dynamics theory,,the performances of 30 mm ceramic-nose projectile and 30 mm standard projectile penetrating into the ceramic/A3 steel composite targets were analyzed and compared using DOP method,especially focusing on the effects made by different nose structures and *** aperture and depth of perforation of projectile into the armor plates as well as the residual mass of bullet core under the same conditions were comparatively analyzed.A numerical simulation was built and computed by ANSYS/*** on the simulated results,the penetration performance was further analyzed in terms of the residual mass of bullet *** results show that the ceramic nose has a great effect on the protection of bullet core.

关键词： Projectile Penetration Ceramic Impact dynamics theory Numerical simulation

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922例无精子症患者的病因诊断及其意义

生殖医学杂志 2009年第2期18卷 119-122页

作者：费前进黄学锋李澄棣张李雅杨旭浙江省温州医学院附属第一医院生殖医学中心温州325000

目的探讨无精子症患者的病因。方法对922例无精子症患者按WHO标准进行病因诊断分析。结果922例无精子症患者中先天性异常445例(48.3%)、特发性无精子症206例(22.3%)、梗阻性无精子症198例(21.5%)、医源性疾病26例(2.8%)、获得性睾丸损... 详细信息

目的探讨无精子症患者的病因。方法对922例无精子症患者按WHO标准进行病因诊断分析。结果922例无精子症患者中先天性异常445例(48.3%)、特发性无精子症206例(22.3%)、梗阻性无精子症198例(21.5%)、医源性疾病26例(2.8%)、获得性睾丸损伤23例(2.5%)、全身性疾病10例(1.1%)、精索静脉曲张8例(0.9%)、内分泌病因6例(0.7%);206例特发性无精子症患者睾丸活检结果,睾丸生精功能低下38例(18.4%)、生精阻滞69例(33.5%)、唯支持细胞综合征(SCOS)90例(43.7%)、生精小管透明变性9例(4.4%)。结论先天性异常、特发性无精子症和梗阻性无精子症是无精子症患者的主要病因,SCOS是特发性无精子症患者睾丸生精障碍的主要病理类型。

关键词：男性无精子病因

Design of a Carbon Nanotube/Magnetic Nanoparticle-Based Peroxidase-like Nanocomplex and Its Application for Highly Efficient Catalytic Oxidation of Phenols

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Nano Research 2009年第8期2卷 617-623页

作者： Xiaolei Zuo cheng Peng Qing Huang Shiping Song lihua Wang di li Chunhai Fan Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

We report a novel nanotechnology-based approach for the highly efficient catalytic oxidation of phenols and their removal from *** use a nanocomplex made of multi-walled carbon nanotubes(MWNTs)and magnetic nanoparticles(MNPs).This nanocomplex retains the magnetic properties of individual MNPs and can be effectively separated under an external magnetic fi *** importantly,the formation of the nanocomplex enhances the intrinsic peroxidase-like activity of the MNPs that can catalyze the reduction of hydrogen peroxide(H2O2).Significantly,in the presence of H2O2,this nanocomplex catalyzes the oxidation of phenols with high effi ciency,generating insoluble polyaromatic products that can be readily separated from water.

关键词： Carbon nanotubes magnetic nanoparticles phenol peroxidase catalysis

Simultaneous LC-MS/MS Determination of Danshensu and Paeoniflorin for Permeability Studies in Caco-2 Intestinal Absorption Model

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Chemical Research in Chinese Universities 2008年第4期24卷 420-426页

作者： liU li ZHAO Xiao-ping ZHU di-feng cheng Yi-yu QU Hai-bin Pharmaceutical Informatics Institute Zhejiang University Hangzhou 310058 P. R. China Department of Basic Medicine Zhejiang Chinese Medical University Hangzhou 310053 P. R.China

A high sensitive method based on liquid chromatography tandem mass spectrometry（LC-MS/MS） was developed and validated for the study of permeability of danshensu（DS） and paeoniflorin（PF） in Caco-2 intestinal absorption model. The DS and PF were extracted from cell culture by vacuum-lyophilizing and then separated on a Zorbax Stable Bond C18 column with 0.1% acetic acid aqueous solution and methanol as mobile phase. Detection was carried out by negative electrospray ionization（ESI ） with selected reaction monitoring（SRM） mode. The apparent permeability coefficients（Papp） of DS and PF in Caco-2 cell medium were calculated and the effects of verapamil on the coefficients Papp of the two test compounds were also illustrated. The permeability of PF was much better than that of DS when the two compounds were administrated individually. Co-administration of DS and PF led to the decrease of the transport from apical side to basolateral side for both the compounds. However, the transport in the contrary direction were accelerated. It was also observed that verapamil could accelerate the transport of the test compounds from apical side to basolateral side. However, the absorption-enhanced effect of verapamil was attenuated when DS and PF were co-administrated. These observations suggest that both passive diffusion and active efflux involved in P-gp would effect the passage of DS and PF across Caco-2 cell monolayer. At the same time, the co-administration of DS and PF to an alteration of transport behavior, which suggests that the interaction must be taken into account when ‘n-in-one＇ samples were used in Caco-2 intestinal model.

关键词： Denshensu Paeoniflorin Caco-2 cell Apparent permeability coefficient LC-MS/MS