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Optimisation of superplastic processing parameters for (Cu_(43)Zr_(48)Al_9)_(98)Y_2 bulk metallic glasses

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Journal of Rare Earths 2019年第1期37卷 95-100,M0005页

作者： Bing Li Xuanxuan Xu Hucheng Zhang Ke Yang xinhui fan Jinshan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Shaanxi Key Laboratory for Photoelectric Functional Materials and Devices Xi'an Technological University Shanxi Jiangyang Chemical Co. Ltd.

In this study,hot compression tests of (Cu_(43)Zr_(48)Al_9)_(98)Y_2 bulk metallic glasses (BMGs) were performed,and their micro structure and thermal properties after the deformation were studied to explore the appropriate range of their optimum processing parameters. The experimental results show that the superplastic deformation of (Cu_(43)Zr_(48)Al_9)_(98)Y_2 bulk metallic glasses depends mainly on the temperature and strain rate. It is suitable for superplastic processing when the alloys are in the state of Newtonian flow and do not crystallise. The appropriate processing parameters of (Cu_(43)Zr_(48)Al_9)_(98)Y_2 BMGs are the temperatures and strain rates, which are below the "dividing line". And when the temperature is above733 K, the strain rate must be>1×10^(-3) s^(-1).

关键词： Bulk metallic glasses Superplastic Flow behaviour Crystallisation behaviour Rare earths

Thermal Analysis by Means of Differential Scanning Calorimetry of the Characteristic Thermodynamic Temperatures of a Cu-Zr-Al Bulk Metallic Glass

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Fluid Dynamics & Materials Processing 2022年第1期18卷 71-80页

作者： Yanhong Li Bing Li xinhui fan Ke Yang Xin Wang Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices School of Material and Chemical EngineeringXi’an Technological UniversityXi’an710021China

In this study a Cu_(43)Zr_(48)Al_(9)bulk metallic glass prepared by the copper mold casting method is *** recent years,Cu-Zr-Al systems like this have enjoyed widespread attention due to their high strength,high hardness,high corrosion resistance and low *** samples of this substance are studied using DSC(Differential scanning calorimetry)to determine the effect of different test conditions(heating rate,sample mass,sample specific surface area and sample crystal phase)on the characteristic thermodynamic temperature of the bulk metallic *** results show that almost all of the five characteristic thermodynamic temperatures(T_(g),T_(x),T_(p),T_(m),T_(l))of this substance have higher values when the heating rate is *** influence of the variation of sample mass,sample specific surface area and sample crystal phase on the amorphous alloy characteristic temperature is very *** the heating rate,the more developed the crystalline phase in the amorphous alloy will be.

关键词： Cu-Zr-Al amorphous influence factors characteristic thermodynamic temperature DSC

Microstructure and texture evolution of cold drawing <110> single crystal copper

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Science China(Technological Sciences) 2011年第6期54卷 1551-1559页

作者： CHEN Jian YAN Wen LI Bing MA XiaoGuang DU XinZhi fan xinhui Department of Applied Physics Northwestern Polytechical University Xi'an 710072 China School of Materials Science and Chemical Engineering Xi'an Technological University Xi'an 710032 China

By means of electron backscattering diffraction and transmission electron microscopy the microstructure and texture of drawn single crystal copper with initial orientation （110） parallel to axial direction have been investigated in the present work. In or- der to analyze the effect of initial orientation on microstructure and texture of drawn copper, the results of the drawn （110） sin- gle crystal copper wires have been compared with （100） and （111） single crystal copper wires. It is found that the grain subdi- vision of （110） single crystal is more evident than that of （100） and （111）, and the textures consisting of （111） and （100） abruptly form in the drawn （110） single crystal. At high strains, due to shear strain, the distribution of fiber textures is imho- mogenous along the radial direction of drawn （110） single crystal copper wires. （100） is near the surface and （111） is at the center. The microstructure results of drawn （110） single crystal show that at low strains, it can be characterized as two kinds of geometrically necessary boundaries with noncrystalline character. At medium strains, S bands can be observed. At high strains, lamellar boundaries form. Mean misofientation and average spacing of dislocation boundary are larger in drawn （110） single crystal, as compared with （111） and （100）. In drawn （110） single crystal with high strains, the bimodal distribution forms at lower strains than in drawn （100） single crystal, which is because the dislocation boundaries with high angle are contributed by not only the boundary between （111） and （100） fiber textures but also the boundary in （111） or （100） texture.

关键词： single crystal copper cold drawing texture microstructure

SUPER Score Contributes to Warning and Management in Early-Stage COVID-19

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Infectious Medicine 2023年第4期2卷 308-314页

作者： Yuan Bian Qi Han Yue Zheng Yu Yao xinhui fan Ruijuan Lv Jiaojiao Pang Feng Xu Yuguo Chen Department of Emergency Medicine Qilu Hospital of Shandong UniversityJinan 250012China Chest Pain Center Shandong Provincial Clinical Research Center for Emergency and Critical Care MedicineInstitute of Emergency and Critical Care Medicine of Shandong UniversityQilu Hospital of Shandong UniversityJinan 250012China Key Laboratory of Emergency and Critical Care Medicine of Shandong Province Key Laboratory of Cardiopulmonary-Cerebral Resuscitation Research of Shandong ProvinceShandong Provincial Engineering Laboratory for Emergency and Critical Care MedicineQilu Hospital of Shandong UniversityJinan 250012China The Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of EducationChinese Ministry of Health and Chinese Academy of Medical SciencesThe State and Shandong Province Joint Key Laboratory of Translational Cardiovascular MedicineQilu Hospital of Shandong UniversityJinan 250012China

Background:Some COVID-19 patients deteriorate to severe cases with relatively higher case-fatality rates,which increases the medical *** necessitates identification of patients at risk of severe *** assessment plays a crucial role in identifying patients at risk of severe *** study is to assess the effectiveness of SUPER score as a predictor of severe COVID-19 ***:We consecutively enrolled COVID-19 patients admitted to a comprehensive medical center in Wuhan,China,and recorded clinical characteristics and laboratory *** SUPER score was calculated using pa-rameters including oxygen saturation,urine volume,pulse,emotional state,and respiratory *** addition,the area under the receiver operating characteristic curve(AUC),specificity,and sensitivity of the SUPER score for the diagnosis of severe COVID-19 were calculated and compared with the National Early Warning Score 2(NEWS2).Results:The SUPER score at admission,with a threshold of 4,exhibited good predictive performance for early identification of severe COVID-19 cases,yielding an AUC of 0.985(95%confidence interval[CI]0.897-1.000),sensitivity of 1.00(95%CI 0.715-1.000),and specificity of 0.92(95%CI 0.775-0.982),similar to NEWS2(AUC 0.984;95%CI 0.895-1.000,sensitivity 0.91;95%CI 0.587-0.998,specificity 0.97;95%CI 0.858-0.999).Com-pared with patients with a SUPER score<4,patients in the high-risk group exhibited lower lymphocyte counts,interleukin-2,interleukin-4 and higher fibrinogen,C-reactive protein,aspartate aminotransferase,and lactate dehydrogenase ***:In conclusion,the SUPER score demonstrated equivalent accuracy to the NEWS2 score in predicting severe *** application in prognostic assessment therefore offers an effective early warning system for critical management and facilitating efficient allocation of health resources.

关键词： COVID-19 Early warning NEWS2 SUPER score

Trends in point-of-care ultrasound protocols in the emergency department and intensive care unit:a review

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Emergency and Critical Care Medicine 2023年第2期3卷 64-69页

作者： xinhui fan Yuan Bian Guoying Wang Weikang Liu Luyao Gao Yuhui Pan Shengchuan Cao Qiuhuan Yuan Shujian Wei Feng Xu Yuguo Chen Department of Emergency and Chest Pain Center Shandong Provincial Clinical Research Center for Emergency and Critical Care MedicineInstitute of Emergency and Critical Care Medicine of Shandong UniversityKey Laboratory of Emergency and Critical Care Medicine of Shandong ProvinceKey Laboratory of Cardiopulmonary-Cerebral Resuscitation Research of Shandong ProvinceQilu Hospital of Shandong UniversityJinanChina.

Together with the development of the focused assessment with sonography for trauma protocol for ultrasound in trauma patients,point-of-care ultrasound is widely used in the field of emergency and critical care *** have established several classic operating protocols for different diseases,such as acute respiratory failure,shock,and cardiac arrest,in the emergency department and intensive care *** further development in the portability and popularity of ultrasonic equipment,it is expected to be used as a new type of technology for physical examination,including inspection,palpation,percussion,auscultation,and insonation,which will improve the clinical medicine practice in the future.

关键词： Auscultation and insonation Inspection Palpation Percussion Point-of-care ultrasound Protocol Seven-point and nineplane protocol

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基于预测差值的医学图像可逆信息隐藏

北京化工大学学报（自然科学版） 2019年第2期46卷 83-89页

作者：范鑫惠李辉北京化工大学信息科学与技术学院北京100029

针对目前医学图像需要对图像中特殊区域进行划分以及在应用于医学图像时效果不稳定、嵌入容量小等问题,结合医学图像的特点,提出一种基于预测差值的可逆信息隐藏算法。首先采用中值边缘预测算法计算预测差值,再根据预测差值的分类进行... 详细信息

针对目前医学图像需要对图像中特殊区域进行划分以及在应用于医学图像时效果不稳定、嵌入容量小等问题,结合医学图像的特点,提出一种基于预测差值的可逆信息隐藏算法。首先采用中值边缘预测算法计算预测差值,再根据预测差值的分类进行信息嵌入和像素平移;在形成载密图像的过程中,为防止像素值溢出,对原始图像进行多次预嵌入来标记所有可能发生溢出的像素点位置,且标记过的像素点不再修改。实验结果表明,本文算法能在保证图像质量的同时获得较高的嵌入量。

关键词：可逆信息隐藏医学图像中值边缘预测预测差值

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添加Y制备铜锆基大块非晶合金（英文）

稀有金属材料与工程 2014年第7期43卷 1558-1561页

作者：李炳李金山范新会陈建西北工业大学凝固技术国家重点实验室陕西西安710072 西安工业大学光电功能材料与器件省级重点实验室陕西西安710021

采用工业级的低纯Zr,通过稀土Y的微合金化作用,制备Cu46Zr46Al8非晶合金。结果表明:Y能有效提升Cu46Zr46Al8合金的玻璃形成能力,主要原因是Y能吸附液态合金中溶解的氧,起到晶化合金的作用。当Y的添加量为2at%,3at%时,效果最为明显。经过... 详细信息

采用工业级的低纯Zr,通过稀土Y的微合金化作用,制备Cu46Zr46Al8非晶合金。结果表明:Y能有效提升Cu46Zr46Al8合金的玻璃形成能力,主要原因是Y能吸附液态合金中溶解的氧,起到晶化合金的作用。当Y的添加量为2at%,3at%时,效果最为明显。经过Y微合金化后的非晶合金的抗压缩断裂强度超过2GPa,高于用高纯原料制备的非晶,但是塑性明显下降。

关键词：块体金属非晶低纯添加Y 玻璃形成能力

OCC技术制备的单晶铜线材冷拔组织TEM分析

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稀有金属材料与工程 2011年第10期40卷 1727-1731页

作者：陈建严文苗健彭渝莉范新会西北工业大学陕西西安710072 西安工业大学陕西西安710032 西安交通大学陕西西安710049

采用TEM系统分析了OCC技术制备的单晶铜线材在冷拔过程中形成的位错胞、几何必须界面以及孪晶,发现当真应变小于0.94时,冷拔单晶铜线材的微观组织为位错胞。当真应变大于0.94时,其微观组织主要包括位错胞和几何必须界面两类组织。其中... 详细信息

采用TEM系统分析了OCC技术制备的单晶铜线材在冷拔过程中形成的位错胞、几何必须界面以及孪晶,发现当真应变小于0.94时,冷拔单晶铜线材的微观组织为位错胞。当真应变大于0.94时,其微观组织主要包括位错胞和几何必须界面两类组织。其中位错胞沿冷拔方向拉长,横界面上为等轴状。随变形量的增加,位错胞尺寸减小,当真应变大于1.39时,位错胞尺寸不再随塑性变形量的增加而减小,其直径保持在0.28μm左右。当变形量比较小时,两类几何必须位错界面属于晶体学界面,当变形量比较大时,几何必须位错界面与冷拔方向平行。同时,分析还发现冷拔单晶铜线材中存在少量由凝固过程形成并遗传到形变组织以及在冷拔过程直接形成的两类孪晶。

关键词：单晶铜线材冷拔变形位错胞几何必须界面孪晶

ZnO纳米线在外加电场下的生长及场发射性能

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华中科技大学学报（自然科学版） 2007年第10期35卷 98-100页

作者：范新会于灵敏严文朱长纯西安工业大学材料与化工学院陕西西安710032 西安交通大学电子与信息工程学院陕西西安710049

在外加电场条件下,利用化学气相沉积法制备出了长径比为400∶1的四角状ZnO纳米线.利用多功能场发射测试仪对ZnO纳米线进行了场发射特性测试,研究了外加电场对ZnO纳米线生长的影响,讨论了ZnO纳米线在强场下的场发射电流强度饱和现象产生... 详细信息

在外加电场条件下,利用化学气相沉积法制备出了长径比为400∶1的四角状ZnO纳米线.利用多功能场发射测试仪对ZnO纳米线进行了场发射特性测试,研究了外加电场对ZnO纳米线生长的影响,讨论了ZnO纳米线在强场下的场发射电流强度饱和现象产生的原因.结果表明:外加电场大大促进了四角状ZnO纳米线在一维方向上的生长,外加电场下制备的ZnO纳米线在电流密度为0.1 mA/cm2的开启场强仅为2.25V/μm,ZnO纳米线在强场下的场发射电流强度饱和现象归因于强场下电子输运速度的饱和.

关键词： ZnO纳米线外加电场场发射性生长四角锥状