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Journal of Advanced Ceramics 2024年第5期13卷 590-601页

作者： Hui Chen yulei Zhang Yanqin Fu Wenhan Gai Junhao zhao Haohui Zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

Ultra-high-temperature ceramic nanowires have shown increasing potential for use as thermal structural ***,novel single-crystal Hf_(0.5)Ta_(0.5)C solid solution nanowires were synthesized and incorporated with a HfC coating to construct a robust structure with Hf_(0.5)Ta_(0.5)C solid solution nanowires uniformly distributed and interconnected within the *** novel Hf_(0.5)Ta_(0.5)C solid solution nanowires could effectively hinder crack propagation through crack tip pinning and crack *** mechanism substantially enhanced the elastic modulus and fracture toughness of the HfC coating by 53.29%and 59.67%,*** toughened HfC coating displayed superior fracture toughness and good interfacial binding strength with the substrate to resist severe oxidation and ***,the high thermal conductivity of the toughened HfC coating promoted heat ***,in comparison to the pure HfC coating,the toughened HfC coating displayed smaller mass and linear ablation rates of−0.35 mg·s^(−1)and−0.46μm·s^(−1),which decreased by 39.66%and 36.98%,*** work not only simultaneously enhances the mechanical properties and ablation resistance of HfC-coated carbon/carbon(C/C)composites but also provides novel prospects for advanced ultrahigh-temperature ceramic nanowires under extreme conditions.

关键词： Hf_(x)Ta_(1−x)C solid solution nanowires HfC coating carbon/carbon(C/C)composites mechanical performance ablationresistance

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实用心脑肺血管病杂志 2019年第11期27卷 93-97页

作者：鞠婧婧李亚南赵宇蕾秦涌唐珩南京医科大学第二附属医院药学部江苏省南京市210003 江苏省如皋市人民医院临床药学室 226500 东部战区总医院(原南京军区南京总医院)药理科江苏省南京市210002 南京医科大学第二附属医院呼吸内科江苏省南京市210003 南京医科大学附属儿童医院呼吸内科江苏省南京市210001

目的分析血浆维生素D水平与儿童哮喘的相关性及布地奈德、异丙托溴铵雾化吸入联合维生素D的治疗效果。方法选取2018年1-6月在南京医科大学第二附属医院就诊的哮喘患儿100例作为病例组,另选取同期在本院体检的健康儿童100例作为健康组;... 详细信息

目的分析血浆维生素D水平与儿童哮喘的相关性及布地奈德、异丙托溴铵雾化吸入联合维生素D的治疗效果。方法选取2018年1-6月在南京医科大学第二附属医院就诊的哮喘患儿100例作为病例组,另选取同期在本院体检的健康儿童100例作为健康组;将哮喘患儿随机分成对照组和研究组,每组50例。对照组患儿给予布地奈德、异丙托溴铵雾化吸入治疗,研究组患儿给予布地奈德、异丙托溴铵雾化吸入联合维生素D滴剂治疗;对照组与研究组患儿疗程均为6个月。比较健康组和病例组儿童血浆维生素D、免疫球蛋白E(IgE)水平及肺功能指标[包括第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、FEV/FVC比值、25%肺活量最大呼气流量(MEF25)及50%肺活量最大呼气流量(MEF50)],并比较对照组和研究组患儿治疗前后肺功能指标、炎性因子[包括白介素2(IL-2)、白介素4(IL-4)、白介素6(IL-6)、干扰素γ(IFN-γ)]及治疗期间哮喘控制良好率、再入院率;血浆维生素D水平与哮喘患儿血浆IgE水平、肺功能指标的相关性分析采用Pearson相关分析。结果(1)病例组患儿血浆维生素D水平及FEV1/FVC比值、MEF25、MEF50低于健康组,血浆IgE水平高于健康组,FEV,和FVC小于健康组(P0.05);但血浆维生素D水平与哮喘患儿血浆IgE水平呈负相关(r=-0.268,P=0.024),与MEF25(r=0.679)、MEF50(r=0.457)呈正相关(P0.05);治疗后研究组患儿FEV1、FVC大于对照组,FEV1/FVC比值、MEF25及MEF50高于对照组(P0.05);治疗后研究组患儿血浆IL-2、IFN-γ水平高于对照组,血浆IL-4、IL-6水平低于对照组(P<0.05)。(5)治疗期间研究组患儿哮喘控制良好率高于对照组,再入院率低于对照组(P<0.05)。结论血浆维生素D水平与儿童哮喘及其小气道阻塞有关,而布地奈德、异丙托溴铵雾化吸入联合维生素D可有效改善哮喘患儿肺功能,减轻炎性反应,提高哮喘控制良好率并降低再入院率。

关键词：哮喘儿童维生素D 布地奈德异丙托溴铵治疗结果肺功能炎性反应

Optical property and spectroscopy studies on the selected lubricating oil in the terahertz range

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Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1938-1943页

作者： TIAN Lu ZHOU QingLi JIN Bin zhao Kun zhao SongQing SHI yulei ZHANG CunLin Department of Materials Science and Engineering China University of PetroleumBeijing 102249China Beijing Key Laboratory for Terahertz Spectroscopy and Imaging Key Laboratory of Terahertz OptoelectronicsMinistry of EducationDepartment of PhysicsCapital Normal UniversityBeijing 100048China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Department of Mathematics and Physics China University of PetroleumBeijing 102249China

The optical property and spectroscopy of selected kinds of lubricating oil are studied based on the terahertz time-domain spectroscopy (THz-TDS) in the spectral range of 0.3-1.6 THz. The samples are classified by their characteristics via the near-infrared spectrum. The experimental results reveal that lubricating oil is more sensitive in the range of terahertz than in the near-infrared,and the specific kinds of lubricating oil can be identified according to their different spectral features in the terahertz range. The THz-TDS technology applied to lubricating oil analysis has potentially significant impact on the petroleum field.

关键词： terahertz near-infrared transform spectrum lubricating oil

Spectrum features of commercial derv fuel oils in the terahertz region

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Science China(Physics,Mechanics & Astronomy) 2012年第2期55卷 195-198页

作者： zhao Hui zhao Kun TIAN Lu zhao SongQing ZHOU QingLi SHI yulei zhao DongMei ZHANG CunLin State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Laboratory of Optic Sensing and Detecting Technology College of ScienceChina University of PetroleumBeijing 102249China Beijing Key Laboratory for Terahertz Spectroscopy and Imaging Key Laboratory ofTerahertz OptoelectronicsMinistry of EducationDepartment of PhysicsCapital Normal UniversityBeijing 100048China International Center for Materials Physics Chinese Academy of SciencesShenyang 110016China

Characteristic spectra in the 0.5-2.5 terahertz (THz) range of three commercial derv fuel oils have been obtained using THz time-domain spectroscopy and calculated using density functional *** simulated results and experimental absorption curves suggest that the skeleton vibration is predominant in the THz region,and the absorption bumps of diesels are a superposition of various *** investigation demonstrates that different diesels can be distinguished using THz time-domain spectroscopy and THz technology is a promising method to detect the composition and properties of diesels via chemical analysis.

关键词： optical constants derv fuel oil time-domain analysis terahertz radiation

二维钼基纳米抗菌材料的可控制备及抗菌机制研究进展

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地球环境学报 2023年第1期14卷 49-61页

作者：高琴姜柳王震宇赵宇蕾张超锋黄宇中国科学院地球环境研究所、中国科学院气溶胶化学与物理重点实验室西安710061 西安地球环境创新研究院西安710061

细菌感染对人体健康构成了极大威胁,超级细菌的耐药问题也愈发严峻,开发新型抗菌制剂已成为业内普遍共识。钼基纳米材料凭借其独特的理化特性和良好的生物相容性,在抗菌领域应用前景广阔。本文从材料结构、制备方法和抗菌机理3个方面综... 详细信息

细菌感染对人体健康构成了极大威胁,超级细菌的耐药问题也愈发严峻,开发新型抗菌制剂已成为业内普遍共识。钼基纳米材料凭借其独特的理化特性和良好的生物相容性,在抗菌领域应用前景广阔。本文从材料结构、制备方法和抗菌机理3个方面综述了二维钼基纳米抗菌材料的研究进展,介绍了物理接触破坏及微环境改变、氧化应激、外源性自由基诱导和金属离子控释4种代表性抗菌机理的研究现状。最后分析了钼基抗菌制剂目前的挑战和未来的发展前景。

关键词：二维钼基纳米材料抗菌机制自由基细菌

Superior synergistic oxidation resistance of medium-entropy carbide ceramic powders rather than multi-phase carbide ceramic powders

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Journal of Advanced Ceramics 2024年第8期13卷 1223-1233页

作者： Jiachen Li Fanyu Lu Tao Li Yanqin Fu Junhao zhao Junshuai Lv yulei Zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China

To date,some questions about medium-entropy carbide ceramics and the corresponding multi-phase carbide ceramics with the same cations and proportions remain *** oxidation behavior,do both have synergistic oxidation abilities and what role does entropy stabilization play in medium-entropy carbides?In this work,the oxidation behaviors of HfC-ZrC-TiC multi-phase carbide(HZT-MPC)and(Hf_(1/3)Zr_(1/3)Ti_(1/3))C medium-entropy carbide(HZT-MEC)powders were *** thermogravimetry(TG)oxidation,the TG curve of HZT-MPC had a bimodal ***"preferential oxidation"of HfC/ZrC occurred within HZT-MPC,followed by the formation of multi-phase oxides(HfO_(2),ZrO_(2),and TiO_(2)).The uneven compositional distribution slowed their solid solution reactions to form Ti-doped(Hf,Zr)O_(2) and(Hf,Zr)TiO_(4).The TG curve of HZT-MEC had a single peak.A uniform compositional distribution at the atomic scale promoted the rapid interdiffusion of oxides,forming Ti-doped(Hf,Zr)O_(2) and(Hf,Zr)TiO_(4) without ZrO_(2),HfO_(2),and TiO_(2) after TG ***,HZT-MEC had a higher onset oxidation temperature(To;470℃)than did HZT-MPC(430℃),and the TG single peak of HZT-MEC was between the TG bimodal peaks of ***,HZT-MEC showed superior oxidation resistance compared to HZT-MPC,which was attributed to the entropy stabilization effect of HZT-MEC suppressing the"preferential oxidation"of HfC/ZrC and the"delayed oxidation"of TiC,promoting the synergistic oxidation ability of multiple principal elements.

关键词： medium-entropy carbide multi-phase carbide synergistic oxidation ability oxidation resistance

Divergent shift of normal alpine meadow exacerbated soil loss of hillslope alpine meadows based on field experiments

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International Soil and Water Conservation Research 2024年第3期12卷 565-577页

作者： yulei Ma Yifan Liu Yunyun Ban Jingxue zhao Zhihua Shi Gaolin Wu State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Soil and Water Conservation Science and Engineering(Institute of Soil and Water Conservation)Northwest A&F UniversityYanglingShaanxi712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourceYanglingShanxi712100China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China State Key Laboratory of Herbage Imrovement and Grassland AgroEosystem and Colegeof EoogyLanzhou UniversyLanzhou730000Chin College of Resources and Environment Huazhong Agricultural UniversityWuhan430070China CAs Center for Excellence in Quaternary Science and Global Change Xi'an710061China

Global climate change and overgrazing are driving shifts in the plant composition of grassland com-munities,which may profoundly affect the function of grassland ecosystems in regulating runoff and soil ***,we examined the shift effects of normal hillslope alpine meadow to shrub and severely degraded meadow states on runoff and sediment generation under natural rainfall conditions,and determined the contributions of plant and soil properties changes to soil erodibility,runoff and sediment generation by in situ rainfall experiment and monitoring on the hillslope of Qinghai-Tibetan *** results showed that normal meadow shift into severely degraded meadow state,mean weight diameter,soil saturated hydraulic conductivity,soil cohesion and soil erodibility K-factor at the topsoil decreased by 70.3%,73.1%,80.3%and-13.1%,respectively,and when normal meadows shift into shrub meadow state,they reduced by 49.1%,-1.3%,49.4%,and-8.3%,*** and soil loss significantly changed by-40.0%and 177.8%when normal meadow shifted into a severely degraded meadow state,while runoff and soil loss significantly changed by+65.0%and+77.8%when normal meadow shifted into a shrub meadow *** findings highlight that the two divergent shifts both increased soil loss compared to the normal hillslope alpine ***,our results indicate that the divergent shifts of normal alpine meadows exacerbated soil erodibility and soil loss of hillslope alpine *** results obtained here offer a novel perspective on the regulation of runoff and soil erosion in the alpine meadow ecosystem.

关键词： Alpine meadow Divergent shifts RunoffSoil erodibility Soil loss

Single-source precursor derived high-entropy metal–carbide nanowires:Microstructure and growth evolution

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Journal of Advanced Ceramics 2023年第11期12卷 2041-2052页

作者： Junhao zhao yulei Zhang Hui Chen Yanqin Fu Qing Miao Jiachen Meng Jiachen Li Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

In recent years,high-entropy metal carbides(HECs)have attracted significant attention due to their exceptional physical and chemical *** combination of excellent performance exhibited by bulk HEC ceramics and distinctive geometric characteristics has paved the way for the emergence of one-dimensional(1D)HECs as novel materials with unique development ***,we successfully fabricated novel(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires derived via Fe-assisted single-sourced precursor *** to the synthesis of the nanowires,the composition and microstructure of(Ti,Zr,Hf,Nb,Ta)-containing precursor(PHECs)were analyzed,and divinylbenzene(DVB)was used to accelerate the conversion process of the precursor and contribute to the formation of HECs,which also provided a partial carbon source for the nanowire ***,multi-branched,single-branched,and single-branched bending nanowires were synthesized by adjusting the ratio of PHECs to *** obtained single-branched(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires possessed smooth surfaces with an average diameter of 130–150 nm and a length of several tens of micrometers,which were a single-crystal structure and typically grew along the[11¯1]***,the growth of the(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires was in agreement with top-type vapor–liquid–solid *** work not only successfully achieved the fabrication of HEC nanowires by a catalyst-assisted polymer pyrolysis,but also provided a comprehensive analysis of the factors affecting their yield and morphology,highlighting the potential application of these attractive nano-materials.

关键词： (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))C nanowires high-entropy metal carbides(HECs) (Ti,Zr,Hf,Nb,Ta)-containing precursors vapor–liquid–solid(VLS)mechanism

Guest editorial:Blockchain-enabled technologies for cyber-physical systems and big data applications

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Digital Communications and Networks 2022年第5期8卷 589-590页

作者： Zheng Yan Qinghua Zheng yulei Wu Yaliang zhao Mohammed Atiquzzaman Xidian University China Xi'an Jiaotong University China University of Exeter UK Henan University China&St.Francis Xavier UniversityCanada University of Oklahoma USA

*** and motivation Cyber-Physical System(CPS)refers to the seamless integration of the physical processes,computational components,and Internet-of-Things(IoT)devices such as sensors,actuators,and so *** of CPS include smart grids,autonomous transportation systems,medical monitoring,process control systems,robotic systems,and automatic pilot avionics.

关键词： autonomous smart IoT

Femtosecond laser-induced periodic surface structures on hard and brittle materials

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Science China(Technological Sciences) 2024年第1期67卷 19-36页

作者： zhao GuoXu WANG Gong LI YunFei WANG Lei LIAN YuDong YU Yu zhao Hui WANG yulei LU ZhiWei Center for Advanced Laser Technology Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Advanced Laser Technology and Equipment Tianjin 300401China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China School of Information and Electrical Engineering Hebei University of EngineeringHandan 056038China

Hard and brittle materials have high hardness,excellent optical stability,chemical stability,and high thermal ***,they have huge application potential in various fields,such as optical components,substrate materials,and quantum information,especially under harsh conditions,such as high temperatures and high *** laser direct writing technology has greatly promoted the development of femtosecond laser-induced periodic surface structure(Fs-LIPSS or LIPSS by a femtosecond laser)applications of hard and brittle materials due to its high precision,controllability,and three-dimensional processing *** far,LIPSSs have been widely used in material surface treatment,optoelectronic devices,and ***,a consensus has not been reached regarding the formation mechanism of LIPSSs on hard and brittle *** this paper,three widely accepted LIPSS formation mechanisms are introduced,and the characteristics and applications of LIPSSs on diamonds,silicon,silicon carbide,and fused silica surfaces in recent years are *** addition,the application prospects and challenges of LIPSSs on hard and brittle materials by a femtosecond laser are discussed.

关键词： laser-induced periodic surface structures hard and brittle materials femtosecond laser