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Achieving excellent strength-ductility synergy in twinned NiCoCr medium-entropy alloy via Al/Ta co-doping

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Journal of Materials Science & Technology 2021年第28期87卷 184-195页

作者： D.D.Zhang h.Wang J.y.Zhang h.xue G.Liu J.Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049PR China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu610041PR China

Alloying is an effective strategy to tailor microstructure and mechanical properties of metallic materials to overcome the strength-ductility trade-off *** this work,we combined a novel alloy design principle,*** pronounced solid solution hardening(SSh)based on the misfit volumes engineering,and simultaneously,architecting the ductile matrix based on the valence electron concentrations(VEC)criterion,to fulfill an excellent strength-ductility synergy for the newly emerging high/medium-entropy alloys(hEAs/MEAs).Based on this strategy,Al/Ta co-doping within NiCoCr MEA leads to an efficient synthetic approach,that is minor Al/Ta co-doping not only renders significantly enhanced strength with notable SSh effect and ultrahigh strain-hardening capability,but also sharply refines grains and induces abnormal twinning behaviors of(NiCoCr)_(92)Al_(6)Ta_(2) *** with the partially twinned NiCoCr MEA,the yield strength(σy)and ultimate tensile strength(σUTS)of fully twinned Al/Ta-containing MEA were increased by~102%to~600 MPa and~35%to~1000 MPa,respectively,along with good ductility beyond 50%.Different from the NiCoCr MEA with deformation twins(DTs)/stacking faults(SFs)dominated plasticity,the extraordinary strain-hardening capability of the solute-hardened(NiCoCr)_(92)Al_(6)Ta_(2) MEA,deactivated deformation twinning,originates from the high density of dislocation walls,microbands and abundance of *** abnormal twinning behaviors,i.e.,prevalence of annealing twins(ATs)but absence of DTs in(NiCoCr)_(92)Al_(6)Ta_(2) MEA,are explained in terms of the relaxation of grain boundaries(for ATs)and the twinning mechanism transition(for DTs),respectively.

关键词： Medium-entropy alloys Mechanical properties Solid solution hardening Twinning behavior Strength-ductility synergy

基于同步辐射光源X射线散射对聚乙醇酸挤出棒材退火条件的优化

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高分子材料科学与工程 2024年第4期40卷 79-92页

作者：骆佳伟周炳王洪学田雨川陈明明胡永峰中石化(上海)石油化工研究院有限公司上海201208

文中用同步辐射光源对聚乙醇酸(PGA)挤出棒材的切片进行广角X射线散射(WAXS)和小角X射线散射(SAXS)表征,研究聚乙醇酸棒材在挤出成型后优选的退火条件,以尽可能消除内应力,改善棒材后续的机械加工性。WAXS结果表明,高温更有利于微观应... 详细信息

文中用同步辐射光源对聚乙醇酸(PGA)挤出棒材的切片进行广角X射线散射(WAXS)和小角X射线散射(SAXS)表征,研究聚乙醇酸棒材在挤出成型后优选的退火条件,以尽可能消除内应力,改善棒材后续的机械加工性。WAXS结果表明,高温更有利于微观应变的减小,但较高温时晶粒尺寸会随退火时间的延长而减小。SAXS结果表明,高温更有利于取向程度的减小,退火时间对取向程度的影响明显弱于退火温度。综合各数据建立目标函数,并利用响应面分析法进行分析。结果表明,在实验范围内,PGA棒材的优选退火条件为200℃退火2h。

关键词：聚乙醇酸退火同步辐射光源 X射线散射响应面分析法

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双聚醚共改性三硅氧烷表面活性剂的合成及性能研究

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仲恺农业工程学院学报 2024年第3期37卷 11-17页

作者：陈润康李思菁陈嘉怡许桂勇陈铧耀仲恺农业工程学院化学化工学院广东广州510225

为了增强聚醚改性三硅氧烷的亲水性和耐酸碱性能,本研究优化其反应条件,探讨双聚醚的比例对聚醚改性三硅氧烷的性能的影响.结果表明双聚醚成功接枝到三硅氧烷上,反应条件优化结果为双聚醚与三硅氧烷的比例1.1∶1、反应温度105℃、反应时... 详细信息

为了增强聚醚改性三硅氧烷的亲水性和耐酸碱性能,本研究优化其反应条件,探讨双聚醚的比例对聚醚改性三硅氧烷的性能的影响.结果表明双聚醚成功接枝到三硅氧烷上,反应条件优化结果为双聚醚与三硅氧烷的比例1.1∶1、反应温度105℃、反应时间5 h、催化剂用量0.0020%,三硅氧烷的转化率为95%.合成的双聚醚共改性三硅氧烷表面活性剂具有低的表面张力,在碱性条件下能够稳定使用;其水溶液的表面张力值达19.3 mN•m^(-1),浊点28℃,在ph 4条件下极易水解,在ph 7和ph 10的环境下能稳定存在30 d.

关键词：有机硅三硅氧烷硅氢加成表面活性剂

Interspecific competition predicts the potential impact of little fire ant Wasmannia auropunctata (Roger) (hymenoptera: Formicidae) invasion on resident ants in southern China

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Insect Science 2023年第5期30卷 1518-1532页

作者： Lei Nie Bamisope Steve Bamisile yuling Li hao Ran Suhang Wang Lei Wang yijuan xu Red Imported Fire Ant Research Center South China Agricultural UniversityGuangzhouChina

The little fire ant Wasmannia auropunctata(Roger)is a major invasive species that seriously threatens the biodiversity of invaded *** was first reported in Chinese mainland in 2022 and its impact on native species is still *** evaluate the impact of *** invasion on the ant communities in southern China,a series of interspecific competition experiments were conducted in this *** individual aggression index and group aggression experiments showed the advantage of *** in competition with 5 resident ants under equal worker *** encountering Anoplolepis gracilipes,Camponotus nicobarensis,Tetramorium bicarinatum,Poly.h.chis dives,and Solenopsis invicta,*** gradually gained a competitive advantage with an increase in its number of *** the group aggression experiments with equal worker numbers,there was a negative correlation between the body length and mortality rate of resident *** results of the foraging behavior experiments showed that *** was able to dominate food resources under competition with Carebara diversa,which also displayed weak competition in the group aggression *** addition,the abilities to recruit workers and retrieve food were inhibited under competition with *** and *** results of the nesting behavior experiments showed that in the 24-h bout of space resource competition,*** was dominant over ***,***,and *** results of this study show that *** has certain advantages in competition for food and space resources over resident ants in southern China,and some resident ant species may be replaced in the future.

关键词： aggression foraging competition interspecific competition nesting compe-tition W.auropunctata

Two New ent-Kaurane Diterpenoids from Isodon adenantha

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Chinese Chemical Letters 2000年第11期11卷 995-996页

作者： Jiang B. xu J.C. yang h. Zhao Q.S. Sun h.D. Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China yunnan Coll. Traditional Chinese M. Kunming 650200 China

Two new ent-kaurane diterpenoids, adenanthins B (1) and C (2), were isolated from the EtOAc extract of Isodon adenantha. Their structures were elucidated by spectroscopic evidences.

关键词： Two New ent-Kaurane Diterpenoids from Isodon adenantha hMBC

Controlled Fabrication of Uniform Digital Nanorods from Precise Sequence-Defined Amphiphilic Polymers in Aqueous Media

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Chinese Journal of Polymer Science 2023年第5期41卷 768-777,I0010页

作者： Qiang-Qiang Shi Xin Zhou Jie xu Ning Wang Jia-Lin Zhang Xiang-Long hu Shi-yong Liu CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Biomedical Engineering and Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China

Compared with spherical micelles,rod/worm-like micelles not only.h.ve extended blood circulation duration,but also exhibit favorable cellular uptake behavior,which is promising for next-generation nanomedicine and ***,the controllable fabrication of narrowly dispersed nanorods in aqueous media is still ***,the methodology of thermal annealing was developed for the fabrication of helical nanorods as well as a series of nanorods with different *** thermal annealing process generally consisted of adding a percentage of organic solvent(10%(V/V)or 20%(V/V))to the digital micellar aqueous dispersion,followed by.h.ating at 90℃for 1 h,then cooling naturally to room temperature,and dialyzing against water to remove the organic ***-handed helical nanorods were afforded by the treatment of 45 nm digital micelles in the presence of 10%(V/V)dioxane,while left-handed helical nanorods were obtained in the presence of 20%(V/V)***,the controlled growth of rod-like digital micelles was achieved after thermal annealing in the presence of different types of organic solvents,and the length of the annealed nanorods was correlated with the types of organic ***,no matter the size of initial digital micelles,they all exhibited similar trend of rod growth in the presence of a certain amount of organic solvent,allowing for controllable formulation of narrowly dispersed *** addition,supramolecular self-assembly by amphiphilic dendritic oligourethane readily fabricated diverse uniform nanorods in aqueous ***,this work provided an attractive methodology to fabricate uniform digital nanorods.

关键词： Sequence-defined amphiphilic polymers Digital nanorods Thermal annealing Dendritic oligourethane Self-assembly

Surface hydrophobic modification of MXene to promote the electrochemical conversion of N_(2) to Nh_(3)

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Journal of Energy Chemistry 2023年第12期87卷 439-449,I0011页

作者： xu Wang Rui Zhang Chaoqun Ma Wei yan yanjiao Wei Jian Tian Min Ma Qing Li Minhua Shao School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong 999077China Energy Institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal PollutionThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong 999077China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005FujianChina College of Chemistry and Chemical Engineering Dezhou UniversityDezhou 253023ShandongChina

hydrophobic treatment of the catalyst surfaces can suppress the competitive hydrogen evolution reaction(hER) during the nitrogen reduction reaction(NRR).In this work,the surface of Ti_(3)C_(2)Ti_(x) MXene is modified by cetyltrimethylammonium bromide(CTAB) and trimethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-trideca fluorooctyl) silane(FOTS) to increase the hydrophobicity of *** ammonia(Nh_(3)) production rate and faradaic efficiency(FE) are improved from 37.62 to 54.01 μg h^(-1)mg_(cat)^(-1).and 5.5% to 18.1% at-0.7 V ***,respectively after surface modification.^(15)N isotopic labeling experiment confirms that nitrogen in produced ammonia originates from N_(2) in the *** excellent NRR activity of surface hydrophobic MXenes is mainly due to surfactant molecules,which inhibit the entry of water molecules and the competitive hER,which have been verified by in situ FT-IR,DFT and molecular dynamics *** strategy provides an ingenious method to design more active NRR electrocatalysts.

关键词： Electrocatalysis Nitrogen reduction reaction Surface hydrophobic modification MXene Ti_(3)C_(2)Ti_(x)

急性心肌梗死患者急诊经皮冠状动脉介入治疗术后发生冠状动脉微循环障碍的早期临床预测技术研究

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实用临床医药杂志 2024年第3期28卷 39-44,50页

作者：王莉吴春苑匡龙宋佳贤任骋徐芳苏州大学附属张家港医院心血管内科江苏张家港215600

目的探讨左室整体纵向应变(LVGLS)联合全球急性冠状动脉事件注册(GRACE)评分预测急诊经皮冠状动脉介入治疗(PCI)术后急性心肌梗死(AMI)患者发生冠状动脉微循环障碍(CMD)的临床价值。方法选取收治的AMI患者90例为研究对象(失访10例,图... 详细信息

目的探讨左室整体纵向应变(LVGLS)联合全球急性冠状动脉事件注册(GRACE)评分预测急诊经皮冠状动脉介入治疗(PCI)术后急性心肌梗死(AMI)患者发生冠状动脉微循环障碍(CMD)的临床价值。方法选取收治的AMI患者90例为研究对象(失访10例,图像质量差筛除4例),最终纳入76例。术后48 h,患者接受左室心肌声学造影(MCE)技术检测。将患者根据冠状动脉微循环灌注情况分为非CMD组(n=53)及CMD组(n=23)。分析比较2组临床数据及超声心动图相关数据。采用多因素Logistic回归分析筛选CMD发生的影响因素,并绘制受试者工作特征(ROC)曲线分析其临床预测价值。结果 76例患者中,发生CMD 23例(30.26%)。CMD组的LVGLS、GRACE评分高于非CMD组,差异有统计学意义(P<0.05)。多因素Logistic回归分析显示,LVGLS、GRACE评分是急诊PCI术后AMI患者发生CMD的独立预测因子。LVGLS预测CMD发生的曲线下面积为0.858(95%CI:0.769~0.948)。LVGLS联合GRACE评分预测CMD发生的曲线下面积为0.891(95%CI:0.815~0.967)。结论 LVGLS是早期评估急诊PCI术后AMI患者CMD发生的独立预测因素,其协同GRACE评分可以提高预测CMD发生的准确性。

关键词：左室整体纵向应变心肌声学造影全球急性冠状动脉事件注册急性心肌梗死冠状动脉微循环障碍

hybridⅡ全主动脉弓修复术治疗Stanford A型主动脉夹层的疗效分析

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武汉大学学报（医学版） 2024年第2期45卷 213-219页

作者：王可鑫胡小平夏军王志维徐鹏阮永乐昌金星闵心平武汉大学人民医院心血管外科湖北武汉430060

目的:探讨hybridⅡ型主动脉弓修复术治疗Stanford A型主动脉夹层的疗效。方法:回顾性分析2020年10月至2021年12月应用hybridⅡ型主动脉弓修复技术治疗41例Stanford A型主动脉夹层患者的临床资料,其中男性29例,女性12例,年龄29~79岁,平均... 详细信息

目的:探讨hybridⅡ型主动脉弓修复术治疗Stanford A型主动脉夹层的疗效。方法:回顾性分析2020年10月至2021年12月应用hybridⅡ型主动脉弓修复技术治疗41例Stanford A型主动脉夹层患者的临床资料,其中男性29例,女性12例,年龄29~79岁,平均(54.51±11.66)岁,发病时间2~96 h。其中合并主动脉瓣关闭不全17例、夹层累及冠状动脉2例、脏器灌注不良5例、下肢供血障碍1例、高血压病36例、糖尿病4例、马方综合征2例。对围术期及随访结果进行分析。结果:手术成功率为100%,行升主动脉置换+主动脉弓去分支(Debranch)+主动脉支架置入术(TEVAR)16例,Bentall+Debranch+TEVAR 5例,窦部成形+升主置换+Debranch+TEVAR 20例。全组无单瘫、截瘫、昏迷等持续性神经功能障碍。术后意识模糊1例、躁动4例、谵妄2例。低氧血症15例、气管切开4例、肾功能衰竭行连续肾脏替代治疗5例。全组无延迟关胸、二次开胸止血及乳糜胸发生。随访6~12月,死亡2例,其中脑出血1例、重症感染1例(肺炎克雷伯杆菌)。结论:hybridⅡ型主动脉弓修复技术治疗Stanford A型主动脉夹层,避免深低温停循环,缩短了手术及体外循环时间,明显降低了围术期并发症发生率及死亡率,近期效果良好。

关键词：主动脉夹层杂交技术全主动脉弓部修复术神经功能障碍内漏