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Dynamic Plastic Deformation (DPD):A Novel Technique for Synthesizing Bulk Nanostructured Metals

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journal of Materials Science & Technology 2007年第6期23卷 771-774页

作者： Nairong TAO ke LU Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

While some superior properties of nanostructured materials （with structural scales below 100 nm） have attracted numerous interests of material scientists, technique development for synthesizing nanostructured metals and alloys in 3-dimensional （3D） bulk forms is still challenging despite of extensive investigations over decades. Here we report a novel synthesis technique for bulk nanostructured metals based on plastic deformation at high Zener-Hollomon parameters （high strain rates or low temperatures）, i.e., dynamic plastic deformation （DPD）. The basic concept behind this approach will be addressed together with a few examples to demonstrate the capability and characteristics of this method. Perspectives and future developments of this technique will be highlighted.

关键词： Nanostructured materials

Antibacterial Properties of an Austenitic Antibacterial Stainless Steel and Its Security for Human Body

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journal of Materials Science & Technology 2007年第3期23卷 333-336页

作者： ke YANG Manqi LV Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

An austenitic antibacterial stainless steel is reported in this paper. The very fine and dispersive ε-Cu precipitations in the matrix of the antibacterial steel after the antibacterial treatment endow the steel with antibacterial function. The antibacterial function is strong, long-term and broad-spectrum, and can be maintained even after repeated wear and long time dipping in water. The steel is safe for human body and could be used widely in daily application.

关键词： Antibacterial Austenitic steel Body security

Short-time Oxidation of Alloy 690 in High-temperature and High-pressure Steam and Water

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journal of Materials Science & Technology 2012年第6期28卷 562-568页

作者： F.Huang j.Q.Wang E.H.Han W.ke State key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The oxidation behavior of alloy 690 exposed to high-temperature and high-pressure steam and water at 280℃ for 1 h was investigated by scanning electron microscopy （SEM）, atomic force microscopy （AFM） and X-ray photoelectron spectroscopy （XPS）. In high-temperature and high-pressure steam, the oxide film is composed of an outermost Ni-rich hydroxides layer, an intermediate layer of hydroxides and oxides enriched in Cr, an inner oxide layer. The film formed in high-temperature water is similar to that in steam, except for missing the Ni-rich hydroxides layer. Samples with different surface finishes （electropolished, mechanically polished, ground, and as-received） were prepared for comparison. A general increase of the oxide thickness with the degree of surface roughness is observed. The equivalent oxide thicknesses lie in the range of 100-200 nm for the as-received samples, 150-250 nm for the samples ground to 400# and 10-20 nm for the samples ground to 1500#, mechanically polished, and electropolished.

关键词： Alloy 690 Oxidation High-temperature water Surface finish X-ray photoelectron spectroscopy (XPS)

Theoretical optimization of micropillar arrays for structurally stable bioinspired dry adhesives

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 124-129页

作者： ke Ni Zhengzhi Wang Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518108China

Inspired by the excellent adhesion performances of setae structure from organisms,micro/nano-pillar array has become one of the paradigms for adhesive *** micropillar arrays are composed of the resin pillars for adhesion and the substrate with different elastic modulus for *** stress singularity at the bi-material corner between the pillars and the substrate can induce the failure of the micropillar-substrate corner and further hinder the fabrication and application of micropillar arrays,yet the design for the stability of the micropillar array lacks systematical and quantitative *** this work,we develop a semi-analytical method to provide the full expressions for the stress distribution within the bi-material corner combining analytical derivations and numerical *** predictions for the stress within the singularity field can be obtained based on the full expressions of the *** good agreement between the predictions and the FEM results demonstrates the high reliability of our *** adopting the strain energy density factor approach,the stability of the pillar-substrate corner is assessed by predicting the failure at the *** the elastic mismatch between the pillar and substrate given in this paper,the stability can be improved by increasing the ratio of the shear modulus of the substrate to that of the *** study provides accurate predictions for the stress distribution at the bi-material corner and can guide the optimization of material combinations of the pillars and the substrate for more stable bioinspired dry adhesives.

关键词： Micropillar array Stability Bi-material corner Dry adhesive

Cu^(2+)污染下农作物叶片特征光谱探究

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光谱学与光谱分析 2025年第1期45卷 264-271页

作者：张超吴轩杨可明齐钒宇夏天中国地质调查局发展研究中心北京100037 中国地质大学(北京)地球科学与资源学院北京100083 全国地质资料馆北京100037 中国矿业大学(北京)地球科学与测绘工程学院北京100083 中国资源卫星应用中心北京100094

为探究重金属胁迫下农作物污染响应的敏感叶型及谱段,设计了室外温室环境下的不同铜胁迫梯度玉米花盆试验。以玉米叶片为探究对象,利用仪器测定了出穂期玉米叶片的高光谱反射率数据以及叶片中重金属含量数据,为研究提供了基础数据。从... 详细信息

为探究重金属胁迫下农作物污染响应的敏感叶型及谱段,设计了室外温室环境下的不同铜胁迫梯度玉米花盆试验。以玉米叶片为探究对象,利用仪器测定了出穂期玉米叶片的高光谱反射率数据以及叶片中重金属含量数据,为研究提供了基础数据。从频率域角度,结合时频分析的方法设计了叶片光谱探测法(LSDM),获得了重金属铜胁迫下敏感叶型及谱段,为农作物重金属监测提供技术支撑。根据玉米的生长过程,从老叶(O)、中叶(M)、新叶(N)光谱350~1300 nm的全谱段和子谱段角度进行探究。(1)对铜胁迫下玉米叶片的高光谱反射率数据进行双微分(SOD)和包络线移除(CR),转换到频率域上,结合时频分析的方法进行Daubechies小波6层分解。(2)根据信号异常点、小波高值点和SODCR曲线高值点,定义玉米叶片的光谱异常参数(SAP)。异常变化反射率ACR(异常反射率与其后一个相邻波段反射率差值的绝对值);异常小波系数AWC(异常小波系数与其后一个相邻波段小波系数差值的绝对值);异常SODCR值ASV(异常点SODCR值与其后一个相邻波段SODCR值差值的绝对值)。通过光谱异常参数与玉米叶片重金属含量的相关关系,探究对铜污染响应敏感的叶型及谱段。结果表明,叶片光谱探测法LSDM能高效地对玉米叶片弱信息进行增强,并准确定位出重金属铜胁迫引起的光谱异常谱段位置,异常变化范围集中在350~800 nm内;光谱异常参数能定量地衡量玉米叶片在重金属铜胁迫下的光谱异常;在不同铜胁迫梯度下,玉米新叶(N)为敏感叶型,敏感谱段为蓝边、绿峰、黄边、红谷。该研究有望为其他谷类农作物及其冠层尺度重金属监测提供技术支撑。

关键词：重金属胁迫玉米叶片高光谱敏感叶型敏感谱段

In Vivo Study on Degradation Behavior and Histologic Response of Pure Magnesium in Muscles

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journal of Materials Science & Technology 2017年第5期33卷 469-474页

作者： Shanshan Chen Lili Tan Bingchun Zhang Yonghui Xia ke Xu ke Yang Institute of Metal Research Chinese Academy of Sciences Department of Radiology The First Affiliated Hospital of China Medical University Key Laboratory of Diagnostic Imaging and Interventional RadiologyLiaoning Province

When an orthopedics device is implanted into bone injury site, it will contact the soft tissue （skeletal muscle, fascia, ligament etc.） except for bone. Magnesium based biodegradable metals are becoming an important research object in orthopedics due to their bioactivity to promote bone healing. In this study, pure Mg rods with and without chemical conversion coating were implanted into the muscle tissue of rabbits. Implants and their surrounding tissues were taken out for weight loss measurement, cross- sectional scanning electron microscopy observation, elemental distribution analysis and histological examination. The results showed that the chemical conversion coating would increase the in vivo cor- rosion resistance of pure Mg and decrease the accumulation of calcium （Ca） and phosphorus （P） elements around the implants. For the bare magnesium implant, both Ca and P contents in the surrounding tissues increased at the initial stage of implantation and then decreased at 12 weeks implantation, while for the magnesium with chemical conversion coating, Ca and P contents in the surrounding tissues de- creased with the implantation time, but were not significant. The histological results demonstrated that there was no calcification in the muscle tissue with implantation of magnesium for up to 12 weeks. The chemical conversion coating not only increased the in vivo corrosion resistance of pure Mg, but also avoided the depositions of Ca and P in the surrounding tissues, meaning that pure magnesium should be biosafe when contacting with muscle tissues,

关键词： Pure magnesium Degradation behavior Histologic response Muscle tissue

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湿热处理改性淀粉的研究进展

食品与发酵工业 2025年第1期51卷 354-362,372页

作者：黄薇刘远晓李萌萌关二旗卞科河南工业大学粮油食品学院河南郑州450001

湿热处理是常见的淀粉物理改性方法,适当的湿热处理可以有效改变淀粉的颗粒结构、分子结构等,从而影响其溶胀、糊化、老化等理化特性,进而改善食品品质。该文首先介绍了湿热处理的原理和特点,然后分析了湿热处理对淀粉结构和理化特性的... 详细信息

湿热处理是常见的淀粉物理改性方法,适当的湿热处理可以有效改变淀粉的颗粒结构、分子结构等,从而影响其溶胀、糊化、老化等理化特性,进而改善食品品质。该文首先介绍了湿热处理的原理和特点,然后分析了湿热处理对淀粉结构和理化特性的影响,最后探讨了湿热处理在面条、面包、饼干等食品加工中的应用,旨在加深对湿热处理的认识,并为促进湿热处理在改性淀粉和提高淀粉基食品安全和品质中的应用提供理论依据和科学建议。

关键词：湿热处理植物淀粉结构理化性质淀粉基食品

不同初加工方法对咖啡豆风味化合物和感官特性的影响

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食品工业科技 2025年第1期46卷 22-32页

作者：肖克翟慧楠胡荣锁于鑫欣董文江宁夏大学食品科学与工程学院、宁夏食品微生物应用技术与安全控制重点实验室宁夏银川750021 中国热带农业科学院香料饮料研究所海南万宁571533 海南省特色热带作物适宜性加工与品质控制重点实验室海南万宁571533 国家重要热带作物工程技术研究中心海南万宁571533

本研究旨在探究不同初加工处理方法对阿拉比卡咖啡理化特性、风味和感官特性的影响。通过电子鼻和感官分析评价不同初加工咖啡样品的感官风味,主成分分析(PCA)对不同初加工方法进行区分,并利用皮尔逊相关系数分析初加工方法与产生的风... 详细信息

本研究旨在探究不同初加工处理方法对阿拉比卡咖啡理化特性、风味和感官特性的影响。通过电子鼻和感官分析评价不同初加工咖啡样品的感官风味,主成分分析(PCA)对不同初加工方法进行区分,并利用皮尔逊相关系数分析初加工方法与产生的风味化合物之间的关系。结果表明,在理化指标方面,不同初加工方法对咖啡样品的总可滴定酸度(TA)、总可溶性固形物(TSS)和pH具有显著影响(P<0.05),其中,湿法加工(CS)的pH最高。初加工方法对咖啡样品中的生物碱、绿原酸和有机酸等风味化合物含量影响较大,干法处理Ⅰ(GA)的咖啡因含量最高(12.32 mg/g DW),蜜处理Ⅰ(MA)拥有最高的葫芦巴碱含量(3.71 mg/g DW),湿法加工(CS)导致咖啡样品具有最低的绿原酸含量和最高的有机酸含量。此外,电子鼻结果显示,不同初加工方法制备的咖啡香气化合物含量差异显著,相较于人工评测,电子感官分析可以更有效地对不同初加工方法进行区分。该研究结果明晰了不同初加工方法对咖啡的化学组成及感官风味的影响,对咖啡风味品质提升及对优质产品的筛选和鉴别具有重要意义。

关键词：阿拉比卡咖啡初加工处理理化特性风味化合物电子感官

A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong Luo Yunsheng Zhao ke Xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and *** assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety *** study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety *** methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk ***,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision *** in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety *** findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system