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Microstructure, martensitic transformation and shape memory effect of polycrystalline Cu-Al-Mn-Fe alloys

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Science China(Technological Sciences) 2021年第2期64卷 400-406页

作者： YANG ShuiYuan hong Shen li MingPei QING XinYu GUO liPeng GUO YiHui WANG CuiPing liU XingJun College of Materials of Xiamen University Shenzhen Research Institute of Xiamen UniversityXiamen 361005China Fujian Key Laboratory of Materials Genome Xiamen UniversityXiamen 361005China State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

In this study, two Cu-Al-Mn-Fe polycrystalline alloys were prepared, and their microstructure, reversible martensitic transformation, mechanical properties and shape memory effects were investigated. The results show that the reversible martensitic transformation temperatures of the studied alloys are between room temperature and 373 K, which are suitable for practical applications. Two typed martensites of 18R and 2H coexist both in two alloys. The bcc β(FeAl) nanoparticles are Fe-rich, Mnrich and Cu-poor, whereas the martensite is Cu-rich, Fe-poor and Mn-poor. The size of nanoparticles ranges from tens to hundreds of nanometers. Full shape recovery property is displayed in Cu-12.9Al-4.5Mn-2.6Fe alloy all the time while applying different deformation from 5% to 8%. The maximum recoverable strain is up to 4.4% with a recovery rate of 100%.

关键词： shape memory alloy microstructure nanoparticles transmission electron microscopy martensitic transformation shape memory effect

Supercritical Fluid Extraction of Total Flavonoids from Leaves of Acanthopanax Senticosus Harms

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Chemical Research in Chinese Universities 2007年第2期23卷 233-236页

作者： liU Chun-ming ZHAO Ji-min li hong-mei SONG Feng-rui Department of Chemistry Changchun Normal University Changchun 130032 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022 P. R. China

The herbal plant Acanthopanax Senticosus Harms is natural herb of Changbaishan in Jilin Province of China, which belongs to the Araliaceae family. As the ingredients of folk medicine, it has long been used to treat a variety of human diseases, such as cerebrovascular disease, diabetes, tumor, isochemic heart diseases, hypertension, rheumatic arthritis, etc. E2,33. Flavonoids, a class of constituent compounds, which have a broad distribution in the nature and are found in Acanthopanax Senticosus Harms, have gained particular attention. A number of studies have shown that flavonoid compounds have wide biological activities, such as anti-aging, anticancer, anti-HIV,

关键词： Supercritical fluid extraction(SFE) Acarahopanax Senticosus Harms Flavonoids

TiN/γ-Fe interface orientation relationship and formation mechanism of TiN precipitates in Mn18Cr2 steel

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China Foundry 2021年第3期18卷 180-184页

作者： Zheng-hui Wang Jing-pei Xie Qian li Wen-yan Wang ai-qin Wang Pei liu School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Center of International Research for Micro-nano Molding Technology Zhengzhou UniversityZhengzhou 450001China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology Henan University of Science and TechnologyLuoyang 471023China

A Mn18Cr2 steel containing TiN precipitates was fabricated by vacuum induction *** morphology of TiN precipitates and the interface orientation relationship between TiN and γ-Fe were characterized by means of SEM,TEM and SAED,and the formation mechanism of TiN precipitates in Mn18Cr2 steel was *** show that the TiN precipitates are more likely to exhibit a cubic-shaped morphology and form both within the grain and at the grain boundary of γ-*** interface orientation relationship between TiN and γ-Fe is determined as follows:(100)_(TiN)//■_(γ-Fe),■_(TiN)//■_(γ-Fe).Because of the smallest interfacialmisfit,the secondary close-packed lane {100} of TiN preferentially combines with the close-packed plane {111} of γ-Fe during the precipitation in order to minimize the interface *** nucleation,the TiN precipitates exhibit cubic appearance due to the fact that the TiN has a FCC structure with rock salt type *** study provides reference for the material design of the austenitic high-manganese steels with excellent yield strength.

关键词： Mn18Cr2 steel TiN precipitates interface orientation relationship interface misfit

Bone marrow mesenchymal stem cells transplantation promotes the release of endogenous erythropoietin after ischemic stroke

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Neural Regeneration Research 2015年第8期10卷 1265-1270页

作者： Wen Lv Wen-yu li Xiao-yan Xu hong Jiang Oh Yong Bang Department of Neurology Sir Run Run Shaw Hospital College of Medicine Zhejiang University Department of Neurology Samsung Medical Center Sungkyunkwan University School of Medicine

This study investigated whether bone marrow mesenchymal stem cell（BMSC） transplantation protected ischemic cerebral injury by stimulating endogenous erythropoietin. The model of ischemic stroke was established in rats through transient middle cerebral artery occlusion. Twenty-four hours later, 1 × 106 human BMSCs（h BMSCs） were injected into the tail vein. Fourteen days later, we found that h BMSCs promoted the release of endogenous erythropoietin in the ischemic region of rats. Simultaneously, 3 μg/d soluble erythropoietin receptor（s EPOR） was injected into the lateral ventricle, and on the next 13 consecutive days. s EPOR blocked the release of endogenous erythropoietin. The neurogenesis in the subventricular zone was less in the h BMSCs ＋ s EPOR group than in the h BMSCs ＋ heat-denatured s EPOR group. The adhesive-removal test result and the modified Neurological Severity Scores（m NSS） were lower in the h BMSCs ＋ s EPOR group than in the heat-denatured s EPOR group. The adhesive-removal test result and m NSS were similar between the h BMSCs ＋ heat-denatured s EPOR group and the h BMSCs ＋ s EPOR group. These findings confirm that BMSCs contribute to neurogenesis and improve neurological function by promoting the release of endogenous erythropoietin following ischemic stroke.

关键词： nerve regeneration stem cells erythropoietin ischemic stroke erythropoietin receptor cell proliferation cytokine Brd U functional recovery NSFC grant neural regeneration

Solid solution strategy modulated defects engineering of(Cr_(1-x)V_(x))_(2)AlC MAX phase toward superior electromagnetic wave absorption

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Rare Metals 2024年第7期43卷 3205-3219页

作者： Ji-lin Gou Yu-Kai Chang Shu liu Peng-Hui li Ping-Hao Cui Qian-Ku Hu li-Bo Wang Xin Zhang Jun-Kai Wang Qi-Xun Xia ai-Guo Zhou School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454003China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Defects engineering is an effective strategy for manipulating electromagnetic parameters and enhancing electromagnetic wave(EMW)absorption ***,the relationship between them is not clear,especially in solid solution *** this work,a series of(Cr_(1-x)V_(x))_(2)AlC MAX phase solid solutions with layered structure were prepared via tuning the ratio of Cr and V to explore their EMW absorption *** experimental results indicated that the doping of V atoms at the M-site could effectively regulate its impedance matching and EMW absorption properties by introducing appropriate numbers of defects in the crystal,such as twin boundaries,dislocations and lattice *** them,if Cr:V=3:1,Cr_(1.5)V_(0.5)AlC,as radar absorption materials,could reach a strong reflection loss of-51.8 dB at the frequency of 12.8 GHz under an ultra-thin thickness of 1.3 *** reflection loss value could attain-10 dB in a wide frequency range of 2.7-18 GHz and thickness range of 1-5 *** addition,after high temperature and acid-alkali immersion treatment,this sample still had good EMW absorption capability,and the effective absorption bandwidth was enhanced from 2.3 to 2.6 GHz after concentrated acid immersion or 3.1 GHz after concentrated alkali *** work has great reference significance for the research and development of high-performance MAX-based EMW absorption materials in harsh environments.

关键词： MAX phases Solid solution Defects engineering Electromagnetic wave absorption Harsh environments

Investigation on the active phase of CoMo catalyst for selective HDS by low temperature in situ FT-IR

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Chinese Chemical Letters 2011年第3期22卷 366-369页

作者： Qiherima Hui Yuan Hui Feng li Yun hong Zhang Guang Tong Xu The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Research Institute of Petroleum Processing SINOPEC Beijing 100083 China Department of Pharmacy Inner Mongolia Medical College Hohhot 010059 China

The CoMo/Al2O3 catalysts with different metal loading were studied by low temperature in situ FT-IR using CO as probe molecule which appears to be a powerful method by giving rise to signals specific for unpromoted and promoted Mo *** result revealed that the increase of CoMoS phase on the catalyst surface improves the HDS activity and *** ratio of active site number of CoMoS and MoS_2 correlates linearly with HDS selectivity,which provides an effective tool for developing industrial selective HDS catalysts.

关键词： FT-IR CO CoMoS HDS selectivity

Realizing high thermoelectric properties in p-type polycrystalline SnSe by inducing DOS distortion

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Rare Metals 2021年第10期40卷 2819-2828页

作者： Yu-Ping Wang Bing-Chao Qin Dong-Yang Wang Tao hong Xiang Gao li-Dong Zhao School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100094China

SnSe crystals have been discovered as one of the most efficient thermoelectric materials due to their remarkable thermal and electrical transports. But the polycrystalline SnSe possesses much lower performance especially for the low carrier mobility and electrical conductivity. We firstly attempted to explain and verify the difference in the electrical conductivity as a function of temperature between p-type crystalline and polycrystalline SnSe by considering the grain boundary effects in the polycrystalline samples. On the basis of 2% Na doping to optimize the carrier concentration, the carrier mobility is improved by further introducing In, leading to enhanced carrier mobility from 3 to 9 cm2·V^(-1)·s^(-1) in polycrystalline SnSe. Moreover, In doping introduces extra resonant levels in SnSe, which increases the density of states near Fermi level and leads to an enhanced band effective mass. Large Seebeck coefficient of ~205 l V·K^(-1) at 300 K and maximum power factor of ~7.5 l W·cm^(-1)·K^(-2) at 773 K can be obtained in the Sn_(0.975)Na_(0.02)In_(0.005) Se sample,leading to a competitively high dimensionless figure of merit(ZT) value exceeding 1.1 at 773 K.

关键词： Thermoelectric p-type polycrystalline SnSe Carrier mobility Resonant effect Band effective mass

The amount effect of catalyst on the urethane reaction of o-hydroxybenzyl alcohol

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Chinese Chemical Letters 2012年第2期23卷 241-244页

作者： Peng Fei Yang Yan hong Yu Shun Ping Wang Tian Duo li Shandong Provincial Key Laboratory of Fine Chemicals Shandong Polytechnic UniversityJinan 250353China School of Business Shandong Polytechnic UniversityJinan 250353China

The urethane reaction of o-hydroxybenzyl alcohol with phenyl isocyanate was monitored with in situ *** dilaurate was used as catalyst and its amount effect was *** was found that there was an obvious induction period before reaction *** was interesting that the time of induction period climbed up and then declined with the increase of dibutyltin dilaurate. When the concentration of dibutyltin dilaurate reached 9.58×10^（-5） mol/L,the induction period disappeared completely and hereafter did not appear any ***,the urethane reaction kinetics was *** the concentration of dibutyltin dilaurate increased,the reaction rate of phenolic group（k_1） increased sharply,but the reaction rate of alcoholic group（k_2） appeared of little change on the whole.k_1 increased about 20-fold,yet k_2 increased about 2-fold when the concentration of dibutyltin dilaurate varied from 9.58×10^（-6） mol/L to 1.92×10~4 mol/L,which made the value of k_1/k_2 enlarge.

关键词： Urethane reaction FT-IR Dibutyltin dilaurate Polymerization

Making Use of Plant uORFs to Control Transgene Translation in Response to Pathogen Attack

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BioDesign Research 2022年第1期2022卷 381-394页

作者： Gan ai Jin liu Xiaowei Fu Tianli li Hai Zhu Ying Zhai Chuyan Xia Weiye Pan Jialu li Maofeng Jing Danyu Shen ai Xia Daolong Dou College of Plant Protection Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China Department of Plant Pathology Washington State UniversityPullmanWA 99164USA

Reducing crop loss to diseases is urgently needed to meet increasing food production challenges caused by the expanding world population and the negative impact of climate change on crop ***-resistant crops can be created by expressing endogenous or exogenous genes of interest through transgenic ***,enhanced resistance by overexpressing resistance-produced genes often results in adverse developmental *** open reading frames(uORFs)are translational control elements located in the 5′untranslated region(UTR)of eukaryotic mRNAs and may repress the translation of downstream *** investigate the function of three uORFs from the 5′-UTR of ACCELERATED CELL 11(uORFsACD11),we develop a fluorescent reporter system and find uORFsACD11 function in repressing downstream gene *** or simultaneous mutations of the three uORFsACD11 lead to repression of downstream translation efficiency at different ***,uORFsACD11-mediated translational inhibition is impaired upon recognition of pathogen attack of plant *** coupled with the PATHOGENESIS-RELATED GENE 1(PR1)promoter,the uORFsACD11 cassettes can upregulate accumulation of Arabidopsis thaliana LECTIN RECEPTOR KINASE-VI.2(AtLecRKVI.2)during pathogen attack and enhance plant resistance to Phytophthora *** findings indicate that the uORFsACD11 cassettes can be a useful toolkit that enables a high level of protein expression during pathogen attack,while for ensuring lower levels of protein expression at normal conditions.

关键词： expressing crops impaired