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GH4738高温合金高通量双锥试样设计及晶粒组织演变

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中国有色金属学报 2024年第1期34卷 169-183页

作者：韩屹章曲敬龙杨成斌王广磊张华江亮陈淑英孟范超烟台大学精准材料高等研究院烟台264005 北京钢研高纳科技股份有限公司变形高温合金事业部北京100081 四川钢研高纳锻造有限责任公司德阳618099

在高温合金领域,双锥试样被广泛用于高通量研究热加工工艺与组织关系。针对GH4738高温合金,本文通过有限元分析,设计了一种在压缩过程中具有较小等效应变速率波动的双锥试样,并研究了其对晶粒尺寸的影响及其温度依赖性,进而研究了在变... 详细信息

在高温合金领域,双锥试样被广泛用于高通量研究热加工工艺与组织关系。针对GH4738高温合金,本文通过有限元分析,设计了一种在压缩过程中具有较小等效应变速率波动的双锥试样,并研究了其对晶粒尺寸的影响及其温度依赖性,进而研究了在变形温度为1000~1160℃、应变速率为2 s^(-1)和14 s^(-1)、工程应变为30%、50%、70%的条件下合金的晶粒演变。结果表明:等效应变速率的波动会影响变形后合金的晶粒尺寸,并且具有变形温度依赖性。所设计的双锥试样有利于精确研究等效应变与晶粒组织关系。热压缩实验表明,合金的软化以非连续动态再结晶为主,热加工窗口为变形温度1030~1080℃、应变速率14 s^(-1)、工程应变50%~70%。

关键词： GH4738高温合金高通量双锥试样热加工工艺晶粒组织

Anti-inflammatory and DNA Repair Effects of Astragaloside IV on PC12 Cells Damaged by Lipopolysaccharide

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Current Medical Science 2024年第4期44卷 854-863页

作者： Hai-long LI Li-hua SHAO Xi chen Meng WANG Qi-jie QIN Ya-li YANG Guang-run ZhanG Yang HAI Yi-hong TIAN department of Geriatrics The Affiliated Hospital of Gansu University of Chinese MedicineLanzhou730000China Key Laboratory for Mining Innovation and Transformation of Traditional Chinese Medicine in Gansu Province and the New Product Creation Engineering Laboratory of Traditional Chinese Medicine in Gansu ProvinceLanzhou730000China department of Neurology the First People’s Hospital of LanzhouLanzhouGansu730000China School of Public Health Gansu University of Chinese MedicineLanzhou730000China People’s Hospital of Gansu Province Lanzhou730000China Scientific Research and Experimental Center Gansu University of Chinese MedicineLanzhou730000China

Objective This study aimed to establish a neural cell injury model in vitro by stimulating PC12 cells with lipopolysaccharide(LPS)and to examine the effects of astragaloside IV on key targets using high-throughput sequence technology and bioinformatics *** PC12 cells in the logarithmic growth phase were treated with LPS at final concentrations of 0.25,0.5,0.75,1,and 1.25 mg/mL for 24 *** morphology was evaluated,and cell survival rates were calculated.A neurocyte inflammatory model was established with LPS treatment,which reached a 50%cell survival ***12 cells were treated with 0.01,0.1,1,10,or 100µmol/L astragaloside IV for 24 *** concentration of astragaloside IV that did not affect the cell survival rate was selected as the treatment group for subsequent *** activity was detected by colorimetry;the expression levels of ERCC2,XRCC4,XRCC2,TNF-α,IL-1β,TLR4,NOS and COX-2 mRNA and protein were detected by RT-qPCR and Western *** differentially expressed genes(DEGs)between the groups were screened using a second-generation sequence(fold change>2,P2 *** The viability of PC12 cells was not altered by treatment with 0.01,0.1,or 1µmol/L astragaloside IV for 24 h(P>0.05).However,after treatment with 0.5,0.75,1,or 1.25 mg/mL LPS for 24 h,the viability steadily decreased(P2,XRCC4,XRCC2,TNF-α,IL-1β,TLR4,NOS,and COX-2 were significantly increased after PC12 cells were treated with 1 mg/mL LPS for 24 h(Phanges were reversed when PC12 cells were pretreated with 0.01,0.1,or 1µmol/L astragaloside IV in PC12 cells and then treated with 1 mg/mL LPS for 24 h(P26 genes were upregulated,while 1287 genes were downregulat

关键词： PC12 cells astragaloside IV inflammation DNA damage

慢病毒载体介导的CXCR7shRNA治疗人结肠癌皮下种植瘤的实验研究

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实用肿瘤杂志 2009年第2期24卷 132-135页

作者：王红鲜陈道瑾杨开焰成伟胡桂中南大学湘雅三医院普外二科湖南长沙410013

目的探讨慢病毒载体介导的CXCR7-shRNA对人结肠癌裸鼠皮下种植瘤生长的抑制作用,为进一步研究以CXCR7为靶点的结肠癌基因治疗奠定基础。方法(1)构建CXCR7-shRNA慢病毒表达载体;(2)建立裸鼠人结肠癌荷瘤模型,计算成瘤率;(3)治疗组移植瘤... 详细信息

目的探讨慢病毒载体介导的CXCR7-shRNA对人结肠癌裸鼠皮下种植瘤生长的抑制作用,为进一步研究以CXCR7为靶点的结肠癌基因治疗奠定基础。方法(1)构建CXCR7-shRNA慢病毒表达载体;(2)建立裸鼠人结肠癌荷瘤模型,计算成瘤率;(3)治疗组移植瘤内注射慢病毒CXCR7-shRNA表达载体并建立阴性对照(注射慢病毒shRNA阴性对照)和空白对照(注射PPS),测量肿瘤体积和动物体质量,计算肿瘤抑制率。结果将HT-29细胞移植到裸鼠背部皮下,成瘤率为100.0%;治疗组裸鼠的肿瘤体积较阴性对照组和空白对照显著缩小(P<0.05)、动物体质量显著增加(P<0.05)、肿瘤抑制率分别为38.0%和34.0%。结论CXCR7-shRNA慢病毒表达载体能显著抑制人结肠癌裸鼠移植瘤的生长;针对CXCR7基因序列设计的siRNA可作为具有开发前途的抗肿瘤新药,其在体实验中CXCR7的作用机制尚需进一步深入探讨。

关键词：结肠肿瘤基因疗法肿瘤抑制病毒疾病模型,动物

Dy含量对(Nd,Dy)_2(Fe,Co,Nb,Ga)_(14)B/α-Fe纳米复合材料微结构和磁性能的影响

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金属功能材料 2002年第6期9卷 11-13页

作者：陈伟高汝伟朱明刚韩广兵冯维存张鹏刘汉强祁焱刘宜华李卫王新林山东大学物理与微电子学院河北师范大学物理系石家庄050016 钢铁研究总院功能材料所

用熔体快淬 +晶化处理的方法制备了不同Dy含量的Nd8-xDyxFe83 5Co2 Nb1Ga1B4 5(x =0 ,0 2 ,0 5 ,0 8,1 0 )纳米复合材料 ,用差动 (扫描 )分析 (DSC)、X 射线衍射 (XRD)、透射电镜 (TEM )等研究了样品的晶化过程及微结构 ,用振动... 详细信息

用熔体快淬 +晶化处理的方法制备了不同Dy含量的Nd8-xDyxFe83 5Co2 Nb1Ga1B4 5(x =0 ,0 2 ,0 5 ,0 8,1 0 )纳米复合材料 ,用差动 (扫描 )分析 (DSC)、X 射线衍射 (XRD)、透射电镜 (TEM )等研究了样品的晶化过程及微结构 ,用振动样品磁强计 (VSM)测量了磁性能。实验结果表明 :硬磁性相的晶化温度随Dy含量的增加逐渐升高 ,在最佳热处理条件下 ,矫顽力随Dy含量的增加首先有较大的提高 ,在Dy含量x >0 8以后增加较缓慢。剩磁随Dy含量的增加逐渐下降 ,在Dy含量x >0 8以后下降更加显著 ,磁能积在x =0 5～ 0 8附近出现峰值。剩磁和矫顽力与Dy含量的非线性关系是由于软、硬磁性晶粒之间交换耦合作用的强弱导致的。

关键词：纳米复合材料微结构磁性能交换耦合作用矫顽力永磁材料镝

Effect of Troglitazone on Expression of Adhesion Molecules and eNOS in Human Saphenous Vein Gaft

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Journal of Huazhong university of Science and technology(Medical Sciences) 2007年第6期27卷 657-659页

作者：陈澍胡志伟张凯伦苏伟孙宗全 department of Cardiovascular Surgery Union Hospital Tongji Medical College Huazhong University of Science and Technology

To investigate whether peroxisome proliferators-activated receptor-γ （PPARγ） ligand Troglitazone can reduce endothelial injury and activation during storage of harvested saphenous vein grafts. Segments of human saphenous vein graft were collected from 9 patients undergoing coronary bypass surgery and then divided into two equal parts of control and test specimens, were stored in ei- ther heparinized blood （control group） or heparinized blood containing 20 μmol/L troglitazone （test group） for 1 h at room temperature. Tissue distribution and protein expression of VCAM-I, ICAM-I, and endothelial nitric oxide synthase （eNOS） were compared using immunohistochemistry and Western blot analysis. Myeloperoxidase （MPO） activity, a marker of neutrophil sequestration in human saphenous vein grafts, was also measured in each group. The expression of ICAM-1 （753±132 versus 7201±934; P〈0.01） , VCAM-1 （3731±294 versus 8292±793; P〈0.01）, and MPO activity （1.52±0.42 U/g, 5.04±1.26 U/g P〈0.01） were significantly lower in test group. In contract, eNOS expression （7983±834 versus 3989±1008; P〈0.01） was significantly higher in test group. PPARγ ligand troglitazone might reduce endothelial injury during the storage period of human saphenous vein grafts.

关键词： Troglitazone adhesion molecule endothelial nitric oxide synthase saphenous vein graft

纳米氧化锌抗血液肿瘤的药理作用及机制研究进展

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药物评价研究 2024年第2期47卷 438-443页

作者：韩晨吕纯懿王腾李宗宏王文浩徐瑞荣山东中医药大学山东济南250014 山东省卫健委中西医结合血液学重点实验室山东中医药大学血液病研究所山东中医药大学附属医院血液病科山东济南250014

纳米氧化锌(ZnO-NPs)是直径在1~100 nm的无机材料,具有靶向肿瘤细胞、对血液肿瘤细胞敏感的特性,而对正常细胞影响较小,在治疗血液肿瘤方面逐渐成为研究热点。ZnO-NPs通过阻滞细胞周期、抑制肿瘤细胞增殖、调控线粒体功能、通过释放Zn^(... 详细信息

纳米氧化锌(ZnO-NPs)是直径在1~100 nm的无机材料,具有靶向肿瘤细胞、对血液肿瘤细胞敏感的特性,而对正常细胞影响较小,在治疗血液肿瘤方面逐渐成为研究热点。ZnO-NPs通过阻滞细胞周期、抑制肿瘤细胞增殖、调控线粒体功能、通过释放Zn^(2+)来影响细胞稳态等进而诱导肿瘤细胞凋亡,从而破坏肿瘤细胞稳态;还可增敏化疗药物,并作为生物传感器,在治疗血液肿瘤方面具有很大潜力。对ZnO-NPs的药理作用及其在抗白血病、多发性骨髓瘤、淋巴瘤中的药理机制进行综述,以期为优化血液肿瘤治疗手段提供新策略。

关键词：纳米氧化锌血液肿瘤靶向肿瘤细胞细胞周期线粒体细胞稳态

Atomic insights into heterogeneous nucleation and growth kinetics of Al on TiB_(2) particles in undercooled Al-5Ti-1B melt

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Journal of Materials Science & technology 2023年第25期156卷 72-82页

作者： Jing Feng Yanfeng han Xiaocang han Xiaodong Wang Shuangxi Song Baode Sun Mingwei chen Pan Liu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China department of Materials Science and Engineering Johns Hopkin UniversityBaltimoreMD 21218USA

Titanium diboride(TiB_(2))is an effective grain refiner of Al alloys in the industry that facilitates casting processes by forming uniformly refined *** our understanding of the underlying refinement mechanisms has advanced,the atomic kinetics of heterogeneous nucleation of Al on TiB2 remains ***,we report atomic-scale observations of the heterogeneous nucleation and growth kinetics of Al on self-formed TiB_(2) particles by in situ heating of undercooled Al-5Ti-1B *** demonstrate that an ordered Al monolayer forms on the Ti-terminated{0001}TiB_(2) surface;then,the surrounding Al atoms are initiated to form an island-shaped Al nucleus with face-centered cubic{111}stacking without the assistance of a Ti-rich buffer *** interfacial lattice mismatch between{111}Al and{0001}TiB_(2) causes remarkable out-of-plane strain that decreases gradually with Al nucleus layers increasing to 6 atomic *** elastic strain energy originating from this interfacial strain increases the free energy of the Al/TiB2 heterostructure,hence impeding the rapid growth of the Al *** found that TiB2 particles stabilize the Al nuclei rather than activating their free growth into grains when the experimental undercoolingΔT is lower than the onset undercoolingΔT fg in Greer's free growth *** findings provide an atomic-scale physical image of the heterogeneous nucleation and growth mechanisms of Al with inoculator participation and elucidate the strain-dependent growth kinetics of Al nuclei.

关键词： In situ tem Heterogeneous nucleation Lattice strain Aluminum TiB2 particles

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连铸板坯中间包喂稀土丝工艺试验研究

稀土 2001年第4期22卷 64-67页

作者：张雪松颜银标陈光陈伟黄一新朱红健马军南京钢铁集团公司技术中心江苏南京210035 南京理工大学材料科学与工程系江苏南京210094

通过化学分析、硫印试验、金相观察及冲击试验 ,分析了中间包喂稀土连铸坯中夹杂物形态、分布 ,并测定了连铸坯横断面上的冲击韧性。研究表明 :中间包喂稀土的连铸坯中 ,稀土分布均匀 ,夹杂物球化效果好、分布均匀 ;冲击韧性明显高于未... 详细信息

通过化学分析、硫印试验、金相观察及冲击试验 ,分析了中间包喂稀土连铸坯中夹杂物形态、分布 ,并测定了连铸坯横断面上的冲击韧性。研究表明 :中间包喂稀土的连铸坯中 ,稀土分布均匀 ,夹杂物球化效果好、分布均匀 ;冲击韧性明显高于未喂稀土的连铸坯 ,尤其是克服了未喂稀土连铸坯内弧侧四分之一范围冲击韧性的大幅降低的问题。

关键词：连铸坯钢中间包喂稀土工艺冲击韧性夹杂物

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三维仿真交互式双臂机器人离线编程系统设计

计算机工程与设计 2018年第7期39卷 2042-2047页

作者：许鹏陈友东合肥职业技术学院计算机系安徽合肥238000 北京航空航天大学机械工程及自动化学院北京100191

针对目前双臂机器人编程存在示教操作繁琐、协调模型构建复杂等问题,提出一种基于QT-Coin3D的双臂机器人离线编程系统,目标是生成机械臂的路径并完成双臂协作的仿真。基于DH参数构建双臂机器人的运动学模型,设计一种通用的双臂机器人仿... 详细信息

针对目前双臂机器人编程存在示教操作繁琐、协调模型构建复杂等问题,提出一种基于QT-Coin3D的双臂机器人离线编程系统,目标是生成机械臂的路径并完成双臂协作的仿真。基于DH参数构建双臂机器人的运动学模型,设计一种通用的双臂机器人仿真控制模型;根据双臂协作操作约束的解耦,对机械臂的轨迹进行解析,提出仿真过程的控制算法,实现仿真协调运动;在仿真完成后生成机器人控制指令,实现双臂机器人本体的运动控制。通过仿真实验验证了该系统的可行性。

关键词：双臂机器人离线编程仿真建模轨迹控制系统设计