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Crystal structure and antibacterial activity of two Gd_(2)complexes based on polydentate Schiff-base ligands
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作者 ZHANG Yingyue KANG Liuqing +2 位作者 YANG Yating GUAN Xiaofen WANG Wenmin 《无机化学学报》 北大核心 2025年第9期1867-1877,共11页
Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene... Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2. 展开更多
关键词 gd_(2)complex polydentate Schiff base crystal structure DNA INTERACTION antibacterial activity
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压力辅助烧结Gd_(2)O_(2)S∶Tb闪烁陶瓷的微结构及性能研究
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作者 吴俊林 黄东 +6 位作者 胡辰 李廷松 杨文钦 蒋兴奋 周健荣 孙志嘉 李江 《人工晶体学报》 北大核心 2025年第12期2119-2126,共8页
Gd_(2)O_(2)S∶Tb闪烁陶瓷具有高的X射线阻止能力、高光输出、优异的光谱匹配性能、低生产成本等优势,是极具应用潜力的安检X射线计算机断层扫描用闪烁材料。本工作以Gd2O3粉体、Tb(NO3)3及H2SO4为原料,通过热水浴还原法合成了Gd_(2)O_(... Gd_(2)O_(2)S∶Tb闪烁陶瓷具有高的X射线阻止能力、高光输出、优异的光谱匹配性能、低生产成本等优势,是极具应用潜力的安检X射线计算机断层扫描用闪烁材料。本工作以Gd2O3粉体、Tb(NO3)3及H2SO4为原料,通过热水浴还原法合成了Gd_(2)O_(2)S∶Tb纳米粉体。采用热压烧结结合热等静压烧结(HIP)后处理制备了纯相Gd_(2)O_(2)S∶Tb陶瓷。系统探究了热压烧结温度(975~1100℃)及HIP后处理温度(1050~1350℃)对Gd_(2)O_(2)S∶Tb陶瓷微观结构、光学透过率及闪烁性能的影响。随着热压烧结温度由975℃升高至1100℃,热压后陶瓷内的气孔数量减少,相对密度由91.4%提升至98.9%。随着HIP温度从1050℃升高至1350℃,Gd_(2)O_(2)S∶Tb陶瓷的相对密度逐渐提高,更高的HIP处理温度促进了陶瓷内气孔的排出。因此,相较于1050和1200℃HIP后处理温度,1350℃HIP后处理的Gd_(2)O_(2)S∶Tb陶瓷光学总透过率更高。经过热压烧结(1050℃×1.5 h,60 MPa)结合HIP后处理(1350℃×3 h,176 MPa Ar气氛)制备的Gd_(2)O_(2)S∶Tb陶瓷(厚度为1 mm)光学总透过率最高,为20.3%@545 nm,由于对闪烁光的有效提取,其也具有最高的X射线激发发光强度。 展开更多
关键词 gd_(2)O_(2)S∶Tb闪烁陶瓷 热水浴法 热压烧结 热等静压烧结 微结构
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强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用及机制研究
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作者 陈建 李慧凛 +4 位作者 应汝炯 董云 沈洁 吴丽琳 盛昭园 《环球中医药》 2026年第1期27-35,共9页
目的通过观察强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用,探讨骨骼肌糖代谢信号途径中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4(mediator complex13/nuclear receptor family 4 member-2/glucose transporter-4,MED... 目的通过观察强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用,探讨骨骼肌糖代谢信号途径中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4(mediator complex13/nuclear receptor family 4 member-2/glucose transporter-4,MED13/Nurr1/GLUT-4)在重症肌无力中的可能的作用机制。方法将鼠L6骨骼肌成肌细胞分离培育好后,分为正常血清组、模型组、空白血清组和强力益气含药血清高、中、低剂量组共6组。除正常血清组外,其余各组均使用H_(2)O_(2)造成氧化损伤,正常血清组与模型组分别换液加入FBS完全培养基培育;空白血清组换液加入正常大鼠血清培育(排除PBS对细胞的影响),强力益气含药血清高、中、低剂量组分别换液加入相应剂量组的大鼠含药血清培育,培养24小时后收集细胞。应用细胞增殖检测、流式凋亡周期检测;分别应用Real-time PCR、免疫荧光、Western blot检测法,检测强力益气血清对L6骨骼肌成肌细PGC-1α、MEF2、MED13、Nurr1、GLUT-4蛋白质定量、定位、定性的表达。结果H_(2)O_(2)处理2小时对L6大鼠肌细胞的增殖有显著的抑制作用(P<0.05),凋亡率显著上升(P<0.05),强力益气颗粒含药血清能够提高H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的增殖率,降低凋亡率。能使MED13基因在转录水平、基因在蛋白水平上出现明显的上调(P<0.05);对于Nurr1基因则是相对模型组降低了其转录水平(P<0.05);对于PGC-1α、MEF2以及GLUT-4,H_(2)O_(2)处理都显著降低了它们的转录水平(P<0.05),含药血清的预处理能够一定程度上逆转这种降低(P<0.05),同时呈现出一定程度上的剂量依赖性。结论强力益气颗粒含药血清通过提高MED13、GLUT-4、PGC-1α、MEF2基因蛋白水平的表达,并且降低Nurr1基因蛋白水平的表达,对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞具有保护作用,从而得出强力益气颗粒含药血清通过干预MED13/Nurr1/GLUT4信号通路,能改善骨骼肌糖代谢,减少骨骼肌细胞损伤,进而改善重症肌无力骨骼肌功能受损的病理状态。 展开更多
关键词 重症肌无力 大鼠L6骨骼肌成肌细胞 强力益气颗粒 骨骼肌糖代谢 中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4信号途径
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掺CeO_(2)稀土钽酸盐陶瓷材料的性能研究
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作者 李凌锋 司瑶晨 +4 位作者 王瑞达 刘广华 赵世贤 李红霞 李虹屿 《材料导报》 北大核心 2026年第2期71-75,共5页
先进航空发动机对热障涂层的服役温度以及抗侵蚀性能有着更高的要求,氧化锆由于其高温红外穿透及高温相变等无法满足日益发展的需要,目前稀土钽酸盐掺杂陶瓷材料作为潜在的高温热障涂层材料而广受关注。本工作提出以四价的氧化铈(CeO_(... 先进航空发动机对热障涂层的服役温度以及抗侵蚀性能有着更高的要求,氧化锆由于其高温红外穿透及高温相变等无法满足日益发展的需要,目前稀土钽酸盐掺杂陶瓷材料作为潜在的高温热障涂层材料而广受关注。本工作提出以四价的氧化铈(CeO_(2))按不同比例掺杂于(Y_(0.5)Gd_(0.5))TaO_(4)材料体系中,通过高温固相反应在1750℃保温5 h,制备单斜相掺CeO_(2)稀土钽酸盐氧化物。研究了该材料的热学和力学性能、显微结构及抗CaO-MgO-Al_(2)O_(3)-SiO_(2)(CMAS)侵蚀性能。结果表明:①掺CeO_(2)稀土钽酸盐陶瓷材料具有低的热导率(1.55 W·m^(-1)·K^(-1))。②掺CeO_(2)稀土钽酸盐陶瓷材料存在铁弹相变,有助于提高材料的断裂韧性。③较低的脆性指数(1.33μm^(-1/2))提高了试样的损伤容限,阻碍材料的变形以及裂纹的扩展。④掺CeO_(2)稀土钽酸盐材料具有优异的抗CMAS侵蚀性能。⑤掺CeO_(2)稀土钽酸盐陶瓷材料是一种极具应用潜力的新型热障涂层材料。 展开更多
关键词 热障涂层 钽酸盐陶瓷 (Y_(0.5)gd_(0.5))TaO_(4) CeO_(2)掺杂 热学性能 力学性能 抗CMAS侵蚀
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超高温热障涂层材料Gd_(2)Zr_(2)O_(7)陶瓷Yb-Zr共掺杂研究
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作者 王星奇 刘宇阳 +3 位作者 彭程 白雪 张欣楠 王星明 《中国稀土学报》 北大核心 2025年第5期1081-1086,共6页
针对新型超高温热障涂层材料(Gd0.9Yb0.1)2Zr2O7热物理性能需要进一步提升的需求,采用Yb-Zr共掺杂优化材料成分,利用热压制备了组成为(Gd_(0.9-0.065x)Yb_(0.1-0.025x))_(2)Zr_(2+0.18x)O_(7+0.09x)(x=0,1,2,3,4)的陶瓷样品。通过X射线... 针对新型超高温热障涂层材料(Gd0.9Yb0.1)2Zr2O7热物理性能需要进一步提升的需求,采用Yb-Zr共掺杂优化材料成分,利用热压制备了组成为(Gd_(0.9-0.065x)Yb_(0.1-0.025x))_(2)Zr_(2+0.18x)O_(7+0.09x)(x=0,1,2,3,4)的陶瓷样品。通过X射线衍射仪、扫描电镜、超声波反射法、激光导热仪、热膨胀仪等方法研究了Yb-Zr共掺杂对Gd_(2)Zr_(2)O_(7)基陶瓷热物理性能的影响,结果表明:Yb-Zr共掺杂不会影响Gd_(2)Zr_(2)O_(7)基陶瓷的物相结构,材料体系仍然为单一的萤石相结构,随着x的增加,晶胞参数减小,材料体系的抗烧结性能提高,杨氏模量从205 GPa降低至105 GPa;x=2时陶瓷在30~1500℃温度段的平均线膨胀系数最大数值10.4×10^(-6)K^(-1);x=3时陶瓷在1100 K下具有最低的热导率1.06 W·(m·K)^(-1),与x=0,1相比,下降了约20%。 展开更多
关键词 热障涂层陶瓷层材料 gd_(2)Zr_(2)O_(7) Yb-Zr共掺杂 热物理性能
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(Y_(1‒x)Gd_(x))_(2)O_(3)对WC增强Ni基复合涂层组织结构及性能的影响
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作者 尹自豪 马兴华 +3 位作者 尹宇 马名浩 张树玲 郭峰 《表面技术》 北大核心 2025年第19期153-162,共10页
目的为了优化WC增强Ni基复合涂层的成型品质及其耐磨耐蚀性能,研究采用激光熔覆技术制备(Y_(1‒x)Gd_(x))_(2)O_(3)/WC/Ni60A复合涂层。方法首先,在25%WC/Ni60A的基础涂层中,添加2%的(Y_(1‒x)Gd_(x))_(2)O_(3)(0.0≤x≤1.0)双元稀土氧化... 目的为了优化WC增强Ni基复合涂层的成型品质及其耐磨耐蚀性能,研究采用激光熔覆技术制备(Y_(1‒x)Gd_(x))_(2)O_(3)/WC/Ni60A复合涂层。方法首先,在25%WC/Ni60A的基础涂层中,添加2%的(Y_(1‒x)Gd_(x))_(2)O_(3)(0.0≤x≤1.0)双元稀土氧化物,利用X射线衍射分析仪(XRD)、扫描电子显微镜(SEM)结合能谱仪(EDS)等表征工具,对涂层的物相组成、微观结构及元素分布进行分析。运用显微维氏硬度计(HV-1000)、摩擦磨损试验机(UMT-3)以及电化学工作站(CHI-760)等,对涂层的耐磨耐蚀性进行测试。结果通过激光熔覆制备的涂层组织致密,且与基体形成了牢固的冶金结合。XRD分析揭示,该复合涂层主要由γ-Ni枝晶和γ相结构的(Fe,Ni)固溶体构成,而在添加(Y_(1‒x)Gd_(x))_(2)O_(3)后,还检测到了Ni_(2)Y、Gd_(2)Fe_(17)Si等化合物的析出。由SEM和EDS的观察分析结果可知,涂层厚度约为1.5 mm,熔覆层无孔洞和裂纹等缺陷,组织分布均匀,未出现元素偏析现象。硬度测试数据表明,随着x值的增大,复合涂层的平均显微硬度呈上升趋势,在x=0.8时达到峰值465.61HV,约为基体硬度的2.3倍。在摩擦磨损测试中,当x=0.8时,复合涂层展现出最低的摩擦系数(约0.45)和最小的磨损率(约2.09×10^(‒3) mm^(3)/(N·m)),较未添加(Y_(1‒x)Gd_(x))_(2)O_(3)的涂层,耐磨损性能提升了58.78%。电化学测试结果则显示,当x=0.2时,复合涂层的耐蚀性能最为优异,此时的自腐蚀电位和自腐蚀电流密度分别为‒0.3872 V和2.192×10^(‒6) A/cm^(2),但随着x值的继续增大,耐蚀性能逐渐减弱。结论双元稀土氧化物的掺入能够显著提升WC/Ni60A涂层的耐磨耐蚀性能,预示着该材料在极端海洋环境下的表面防护领域具有广阔的应用前景。 展开更多
关键词 激光熔覆 WC/Ni60A涂层 (Y_(1‒x)gd_(x))_(2)O_(3)双元稀土氧化物 组织结构 耐磨耐腐蚀性能
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Hydrogenation of CO_(2) to formate catalyzed by N⁃heterocyclic carbene⁃nitrogen⁃phosphine chelated iridium(Ⅰ)complexes
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作者 GONG Huihua CUI Tianhua +6 位作者 JI Li ZHANG Jichuan ZHANG Liyuan CHEN Yan WANG Zhenye XU Jiaqi LI Ruixiang 《无机化学学报》 北大核心 2025年第12期2609-2620,共12页
To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)... To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)and a 1,5‑cyclooctadiene(cod)molecule:[Ir(cod)(κ^(3)‑CN^(im)P)]Cl(1⁃Cl),[Ir(cod)(κ^(3)‑CN^(im)P)]PF6(1⁃PF_(6)),and[Ir(cod)(κ^(3)‑CNHP)]Cl(2).The^(1)H NMR spectra,^(31)P NMR spectra,and high‑resolution mass spectra verify the successful synthesis of these three Ir(Ⅰ)‑CNP complexes.Furthermore,single‑crystal X‑ray diffraction analysis confirms the coordination geometry of 1⁃PF_(6).The strong Ir—C(NHC)bond suggests that the carbene carbon plays an enhanced anchoring role to iridium due to its strongσ‑donating ability,which helps stabilize the active metal species during CO_(2)hydrogenation.As a result,the Ir(Ⅰ)‑CNP complex exhibits remarkable activity and long catalytic lifetime for the hydrogenation of CO_(2)to formate,reaching a turnover number(TON)of 1.16×10^(6)after 150 h at a high temperature of 170℃,which was a relatively high value among all the Ir complexes.CCDC:2384071,1⁃PF_(6). 展开更多
关键词 CO_(2)hydrogenation iridium complex CNP ligands homogeneous catalysis
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反铁磁Gd_(2)Zn_(17)的单晶生长与各向异性表征
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作者 甄志璇 《磁性材料及器件》 2025年第1期8-13,共6页
通过锌助熔剂法成功生长出Gd_(2)Zn_(17)单晶,采用X射线衍射仪与能量色散X射线能谱仪对其进行了结构与成分表征。进一步系统地对Gd_(2)Zn_(17)单晶样品的磁性与电输运性质进行了测试,磁化率与电阻的温度依赖特性表明反铁磁转变温度T_N=9... 通过锌助熔剂法成功生长出Gd_(2)Zn_(17)单晶,采用X射线衍射仪与能量色散X射线能谱仪对其进行了结构与成分表征。进一步系统地对Gd_(2)Zn_(17)单晶样品的磁性与电输运性质进行了测试,磁化率与电阻的温度依赖特性表明反铁磁转变温度T_N=9.3 K。并且,Gd_(2)Zn_(17)单晶表现出了磁各向异性与电阻各向异性:对于磁场平行c轴方向,磁化和磁电阻都在3.9 T附近出现了明显的变磁相变点H_c,意味着该磁场附近可能形成了特殊的磁结构;而对磁场垂直c轴方向则没有观察到类似的现象。各向异性的磁相图揭示了其晶体内部可能具有复杂的自旋纹理,为将来进一步探究其中的磁相互作用以及背后的物理机制提供了线索,为未来相关的稀土化合物的研究与应用奠定了基础。 展开更多
关键词 gd_(2)Zn_(17)单晶 变磁相变 各向异性 磁性 电输运
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Inhibition of the Arp2/3 Complex Attenuates Angiotensin Ⅱ-Induced Cardiomyocyte Hypertrophy
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作者 LING Li PAN Cong-Bin +2 位作者 WAN Lu-Xuan YANG Zhuang-Zhuang REN Zhan-Hong 《中国生物化学与分子生物学报》 北大核心 2025年第9期1332-1341,I0003-I0007,共15页
Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarge... Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarged cardiomyocyte.Effective intervention targets for abnormally enlarged cardiomyocyte remain to be identified.Previous studies have shown that the cellular shape and size can be regulated by the actin related protein 2/3(Arp2/3)complex,which is an actin-binding protein complex involved in the actin nucleation and assembly.However,the roles of the Arp2/3 complex in cardiomyocyte hypertrophy remain unknown.Here our study identifies its novel roles in the occurrence and development of cardiomyocyte hypertrophy.We found that mRNA levels of all subunits from the Arp2/3 complex are significantly upregulated(P<0.05)in the angiotensin Ⅱ(Ang Ⅱ)-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy.Further studies showed that siRNA-directed ARPC 2 silencing inhibits the reactivation of fetal genes and enlargement of cardiomyocyte area induced by Ang Ⅱ in neonatal rat primary cardiomyocytes(NRCMs)and H9c2 cells(P<0.05).In addition,the upstream activators of the Arp2/3 complex including SH3 protein interacting with Nck,90 kD(SPIN90)and Ras-related C3 botulinum toxin substrate 1(Rac1)/WASp family Verprolin-homologous protein-2(WAVE-2)are upregulated(P<0.05)in Ang Ⅱ-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy,indicating the excessive activation of the Arp2/3 complex.We further show that CK666,a specific Arp2/3 complex inhibitor,prevents the reactivation of fetal genes and the enlargement of cardiomyocyte area induced by Ang Ⅱ in NRCMs and H9c2 cells(P<0.05).Our results reveal that the Arp2/3 complex plays a crucial role in Ang Ⅱ-induced cardiomyocyte hypertrophy,which is beneficial to further studies about the molecular mechanisms by which the Arp2/3 complex regulates pathological cardiac hypertrophy. 展开更多
关键词 cardiomyocyte hypertrophy Arp2/3 complex angiotensinⅡ(AngⅡ) neonatal rat primary cardiomyocytes(NRCMs) H9c2 cells
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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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不同粘结层对Yb_(2)O_(3)改性Gd_(2)Zr_(2)O_(7)热障涂层的热冲击影响行为
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作者 李婷玥 王鑫 +2 位作者 甄真 李娜 许振华 《真空》 2025年第1期26-36,共11页
(Yb_(0.1)Gd_(0.9))_(2)Zr_(2)O_(7)(YbGdZrO)稀土复合氧化物是一类适用于1200℃以上应用的新型热障涂层(TBCs)材料。采用电子束物理气相沉积(EB-PVD)工艺在NiCoCrAlYHf及(Ni,Pt)Al粘结层表面分别沉积YbGdZrO陶瓷层,制备出两种不同粘结... (Yb_(0.1)Gd_(0.9))_(2)Zr_(2)O_(7)(YbGdZrO)稀土复合氧化物是一类适用于1200℃以上应用的新型热障涂层(TBCs)材料。采用电子束物理气相沉积(EB-PVD)工艺在NiCoCrAlYHf及(Ni,Pt)Al粘结层表面分别沉积YbGdZrO陶瓷层,制备出两种不同粘结层体系的TBCs试样,并对涂层的显微形貌、化学成分、相结构、残余应力和热冲击行为进行了表征分析。结果表明,NiCoCrAlYHf粘结层表面高低起伏,所沉积的陶瓷层呈“菜花状”织构,紊乱度较高;(Ni,Pt)Al粘结层表面呈平缓的“背脊”形貌,所沉积陶瓷层的柱状晶排列紧密且平整度趋于一致;两种涂层的陶瓷层中Gd和Zr元素含量均与靶材成分较为接近,但Yb元素受沉积温度影响相差较大;随热冲击次数增加,NiCoCrAlYHf/YbGdZrO涂层表面显微裂纹萌生并扩展,且出现点蚀坑,(Ni,Pt)Al/YbGdZrO涂层仍较为平整,无显微裂纹和烧结致密化现象;热冲击1000次后,两种涂层中均出现热生长氧化物(TGO)层,继续热冲击至2500次时,(Ni,Pt)Al粘结层体系的TGO层平均厚度增量仅为1.08μm;NiCoCrAlYHf/YbGdZrO涂层的TGO层残余应力均比同等条件下(Ni,Pt)Al/YbGdZrO的小;两种TBCs的陶瓷层组成元素均已内扩散至粘结层,并少量存留在TGO层内,(Ni,Pt)Al/YbGdZrO涂层所形成的Al_(2)O_(3)膜对Gd元素表现出更强的阻扩散作用。 展开更多
关键词 热障涂层 改性锆酸钆 金属粘结层 热冲击 微观组织
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Effect of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on theexpression of gastrin content and phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin complex 2 signallingpathways in rats with chronic atrophic gastritis
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作者 ZHOU Xia LIANG Kaiqing +4 位作者 CHEN Weigang CAO Yong DUO Hongdong LI Qiangbin AN Yun 《Journal of Traditional Chinese Medicine》 2025年第4期770-776,共7页
OBJECTIVE:To investigate the effects of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on chronic atrophic gastritis(CAG)in rats and its modulation of the phosphatidylinositol 3-kinase/protein kinase B/mechanistic tar... OBJECTIVE:To investigate the effects of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on chronic atrophic gastritis(CAG)in rats and its modulation of the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin complex 2(PI3K/Akt/m TORC2)signaling pathway.METHODS:CAG was induced in rats and treated with high-,medium-,or low-dose Jiawei Huangqi Guizhi decoction.Gastric histopathology was observed by hematoxylin and eosin staining.Serum levels of gastrin,PI3K,Akt,and m TORC2 were detected by enzyme-linked immunosorbent assay.Gene and protein expression levels were analyzed by reverse transcription polymerase chain reaction and western blot.RESULTS:The decoction alleviated gastric mucosal injury,reduced inflammation,and restored epithelial structure.It regulated PI3K,Akt,and m TORC2 expression at both m RNA and protein levels.CONCLUSION:Jiawei Huangqi Guizhi decoction may prevent CAG progression by improving gastric tissue and modulating the PI3K/Akt/m TORC2 signaling pathway. 展开更多
关键词 GASTRINS PI3K Akt mechanistic target of rapamycin complex 2 signal transduction PATHOLOGY Jiawei Huangqi Guizhi decoction
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Numerical investigations on T_(1)-T_(2)^(*)-based petrophysical evaluation in shale oil reservoir with complex minerals
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作者 Ji-Long Liu Ran-Hong Xie +5 位作者 Jiang-Feng Guo Chen-Yu Xu Guo-Wen Jin Xiang-Yu Wang Bo-Chuan Jin Xiao-Long Ju 《Petroleum Science》 2025年第11期4538-4554,共17页
It is of great significance to evaluate the petrophysical properties in shale oil reservoir,which can contribute to geological storage CO_(2).Two-dimensional nuclear magnetic resonance(2D NMR)technology has been appli... It is of great significance to evaluate the petrophysical properties in shale oil reservoir,which can contribute to geological storage CO_(2).Two-dimensional nuclear magnetic resonance(2D NMR)technology has been applied to petrophysical characterization in shale oil reservoir.However,limitations of traditional 2D NMR(T_(1)-T_(2)or T_(2)-D)in detecting short-lived organic matter and the complexity of mineral compositions,pose NMR-based petrophysical challenges.The organic pores were assumed saturated oil and the inorganic pores were assumed saturated water,and the numerical algorithm and theory of T_(1)-T_(2)^(*)in shale oil reservoir were proposed,whose accuracy was validated through T_(2),T_(1)-T_(2)and T_(2)^(*)experiments.The effects of mineral types and contents on the T_(1)-T_(2)^(*)responses were firstly simulated by the random walk algorithm,revealing the NMR response mechanisms in shale oil reservoir with complex mineral compositions at different magnetic field frequency(f).The results indicate that when the pyrite content is 5.43%,dwell time is 4μs,the f is 200 MHz,and echo spacing is 0.4 ms,the T_(1)-T_(2)^(*)-based porosity is 2.39 times that of T_(1)-T_(2)-based porosity.The T_(2LM)^(*)is 0.015 ms,which is 0.015 times that of T_(2)LM.The T_(1LM)is 8.84 ms,which is 0.63 times that of T_(1LM).The T_(1)-T_(2)^(*)-based petrophysical conversion models were firstly created,and the foundation of petrophysical conversion was laid at different f. 展开更多
关键词 Shale oil complex minerals T_(1)-T_(2)^(*) Petrophysical parameters Frequency conversion
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Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),a new burbankite mineral from carbonatite-syenite complex in Shaxiongdong,Hubei,China
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作者 Jie Dai Xiao-dong Pan +10 位作者 Tong Wang Guo-wu Li Guan Wang Shang-ke Xie Jing Ren Kun-yang Wang Ting Li Tao Wang Jia-le He Jin-sha Xu Gan-fu Shen 《China Geology》 2025年第4期797-805,共9页
Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with... Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with calcite,K-feldspar,albite,aegirine,apatite,and ancylite-(Ce)(?)and strontianite etc.Lishiite is brittle with conchiform fracture and has a Mohs hardness of approximately 4 and none cleavages were observed.The Vickers microhardness(VHN10)is 197.42 kg/mm^(2)(range:166.88 kg/mm^(2) to 214.58 kg/mm^(2)),and the calculated density of lishiite is 3.696 g/cm3.Hand specimen of lishiite are yellow-brown.The empirical chemical formula of the lishiite is ^(A)(Ca_(1.18)Sr_(0.25)Na_(0.19□1.38))_(Σ3.00)^( B)[Sr_(2.17)(Ce_(0.42)La_(0.24)Nd_(0.09)Eu_(0.01))_(Σ0.76) Ba_(0.07)]_(Σ3.00)(C_(5.05)O_(15)).As a member of the burbankite group,the general formula of lishiite follows the general formula A_(3)B_(3)(CO_(3))_(5),where A=Na,Ca,or and B=Sr,Ba,REE,or Ca.Its crystal structure is hexagonal(space group P6_(3)mc)with unit cell parameters a=10.4898(5)Å,c=6.4167(5)Å,and V=611.47(6)Å^(3),characterized by layers of AO_(8) and BO_(10) polyhedra connected to[CO_(3)]^(3−)groups.The discovery of lishiite provides new insights into the evolutionary history of rare earth element(REE)carbonate deposit formation. 展开更多
关键词 Lishiite (Ca_(2)□)Sr_(3)(CO_(3))_(5) New mineral species Burbankite group Carbonatite-syenite complex Mineral exploration engineering Shaxiongdong
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ZMIZ2/MCM3 Axis Participates in Triple-Negative Breast Cancer Progression
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作者 Xiaopan Zou Meiyang Sun +3 位作者 Xin Jiang Jingze Yu Xiaomeng Li Bingyu Nie 《Oncology Research》 2026年第1期297-324,共28页
Objective:Triple-negative breast cancer(TNBC)is highly aggressive and lacks an effective targeted therapy.This study aimed to elucidate the functions and possible mechanisms of action of zinc finger miz-type containin... Objective:Triple-negative breast cancer(TNBC)is highly aggressive and lacks an effective targeted therapy.This study aimed to elucidate the functions and possible mechanisms of action of zinc finger miz-type containing 2(ZMIZ2)and minichromosome maintenance complex component 3(MCM3)in TNBC progression.Methods:The relationship between ZMIZ2 expression and clinical characteristics of TNBC was investigated.In vitro and in vivo experiments were performed to investigate the role of ZMIZ2 dysregulation in TNBC cell malignant behaviors.The regulatory relationship between ZMIZ2 and MCM3 was also explored.Transcriptome sequencing was performed to elucidate possible mechanisms underlying the ZMIZ2/MCM3 axis in TNBC.Results:High ZMIZ2 expression levels were associated with the malignant degree of TNBC.ZMIZ2 overexpression promoted TNBC cell proliferation,migration,and invasion;inhibited apoptosis;and induced G1 phase cell cycle arrest,whereas knockdown of ZMIZ2 had the opposite effect.ZMIZ2 directly targeted and positively regulated MCM3 expression.MCM3 knockdown reversed the effect of ZMIZ2 overexpression on TNBC tumor growth both in vitro and in vivo.High MCM3 expression levels were linked to the degree of malignancy and poor prognosis in TNBC.The differentially expressed genes associated with the ZMIZ2/MCM3 axis were significantly enriched in multiple pathways,such as the mitogen-activated protein kinase(MAPK),mechanistic target of rapamycin(mTOR),Wnt,and Ras signaling pathways,as verified by The Cancer Genome Atlas data.Conclusions:ZMIZ2 and MCM3 were highly expressed in TNBC.ZMIZ2 promoted the development by positively regulating MCM3 expression.Key pathways,such as the Ras/MAPK,phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mTOR,and Wnt signaling pathways,may be key downstreammechanisms. 展开更多
关键词 Triple-negative breast cancer zinc finger miz-type containing 2 minichromosome maintenance complex component 3 pathway enrichment analysis
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急性ST段抬高型心肌梗死患者心电碎裂QRS波与血清sST2蛋白的诊断价值
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作者 倪云杰 李小燕 +3 位作者 何晓兰 张华 胡炜律 辛沙 《中国急救医学》 2026年第1期36-40,共5页
目的探讨急性ST段抬高型心肌梗死患者碎裂QRS波(fQRS)与可溶性生长刺激表达基因2蛋白(sST2)的诊断价值。方法选择2023年1月至2024年10月杭州市富阳区第一人民医院收治的178例急性ST段抬高型心肌梗死患者为观察组,另选医院同期收治的186... 目的探讨急性ST段抬高型心肌梗死患者碎裂QRS波(fQRS)与可溶性生长刺激表达基因2蛋白(sST2)的诊断价值。方法选择2023年1月至2024年10月杭州市富阳区第一人民医院收治的178例急性ST段抬高型心肌梗死患者为观察组,另选医院同期收治的186例心肌炎患者为常规组,入组后检测两组心电图fQRS和sST2水平,收集两组的一般资料(年龄、性别、体重指数、高血压、吸烟、基础疾病等),以多因素Logistic回归分析急性ST段抬高型心肌梗死的影响因素,绘制受试者工作特征(ROC)曲线,以曲线下面积(AUC)评估心电图fQRS和sST2及二者联合对急性ST段抬高型心肌梗死的诊断价值。结果观察组心电图fQRS和sST2水平高于常规组(P<0.05),年龄、中性粒细胞与淋巴细胞比值(NLR)、修正休克指数(MSI)、中性粒细胞与高密度脂蛋白胆固醇比值(NHR)、发病到入院时间、入院时急性冠脉事件全球注册(GRACE)评分高于常规组(P<0.05);多因素Logistic分析结果显示,NLR、MSI、fQRS和sST2为急性ST段抬高型心肌梗死的危险因素(P<0.05);ROC曲线结果显示,心电图fQRS和sST2及二者联合预测急性ST段抬高型心肌梗死发生的AUC分别为0.722、0.725、0.797(P<0.05)。结论心电图fQRS和sST2可用于预测急性ST段抬高型心肌梗死的发生,且二者联合的诊断价值更高。 展开更多
关键词 心电碎裂QRS波 急性ST段抬高型心肌梗死 可溶性生长刺激表达基因2蛋白 诊断价值
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稀土离子掺杂Gd_(2)O_(2)S闪烁陶瓷的研究进展 被引量:4
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作者 李江 丁继扬 黄新友 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2021年第8期789-806,共18页
稀土离子掺杂Gd_(2)O_(2)S闪烁陶瓷是20世纪80年代以后发展的硫氧化物闪烁体。高密度和高热中子吸收截面的Gd_(2)O_(2)S基质具有高的X射线和热中子阻止能力,稀土离子(Pr^(3+)、Tb^(3+)等)的掺杂使其表现出快衰减或高光产额等特性,在闪... 稀土离子掺杂Gd_(2)O_(2)S闪烁陶瓷是20世纪80年代以后发展的硫氧化物闪烁体。高密度和高热中子吸收截面的Gd_(2)O_(2)S基质具有高的X射线和热中子阻止能力,稀土离子(Pr^(3+)、Tb^(3+)等)的掺杂使其表现出快衰减或高光产额等特性,在闪烁领域的应用中占据着重要地位。硫氧化合物的组分控制一直是其合成过程中需要解决的关键问题,Gd_(2)O_(2)S材料的高熔点和S元素挥发严重的问题,限制了高光学质量和优良闪烁性能单晶的制备,因此陶瓷是Gd_(2)O_(2)S闪烁体的主要应用形式。颗粒小、粒径分布窄且低团聚的纯相Gd_(2)O_(2)S粉体是高质量闪烁陶瓷烧结的关键,单纯提高烧结温度制备的Gd_(2)O_(2)S闪烁陶瓷会产生大量的硫空位和氧空位,降低材料的闪烁性能。制备Gd_(2)O_(2)S闪烁陶瓷通常需要压力辅助烧结,这种苛刻的制备条件提高了生产成本。本文介绍了闪烁体的闪烁机理及研究概况,着重综述了Gd_(2)O_(2)S闪烁陶瓷的制备工艺、缺陷的解决方法以及在中子成像和医学X-CT领域的研究现状及应用情况,最后对全文进行总结并对Gd_(2)O_(2)S闪烁陶瓷发展前景进行了展望。 展开更多
关键词 gd_(2)O_(2)S闪烁陶瓷 可控制备 缺陷控制 中子成像 医学X-CT 综述
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Influence of pyrolytic carbon coatings on complex permittivity and microwave absorbing properties of Al_2O_3 fiber woven fabrics 被引量:5
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作者 丁冬海 周万城 +1 位作者 罗发 朱冬梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期354-359,共6页
The pyrolytic carbon (PyC) coatings were fabricated on A1203 fiber fabrics by the method of chemical vapor deposition (CVD). The microstructures of A1203 fibers with and without PyC coatings were characterized by ... The pyrolytic carbon (PyC) coatings were fabricated on A1203 fiber fabrics by the method of chemical vapor deposition (CVD). The microstructures of A1203 fibers with and without PyC coatings were characterized by SEM and Raman spectroscopy. The influence of deposition time of PyC on the DC conductivity (ad) of A1203 filaments and complex permittivity of fabrics at X band (8.2-12.4 GHz) were investigated. The values of Crd and complex permittivity increase with increasing deposition time of PyC. The electron relaxation polarization and conductance loss were supposed to be contributed to the increase of ε' and ε", respectively. In addition, the reflection loss (RL) of fabrics was calculated. The results show that the microwave absorbing properties of Al2O3 fiber fabrics can be improved by PyC coatings. The best RL results are for 60 min-deposition sample, of which the minimum value is about -40.4 dB at about 9.5 GHz and the absorbing frequency band (AFB) is about 4 GHz. 展开更多
关键词 complex permittivity pyrolytic coating Al2O3 fiber fabric
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mTOR Complex1-S6K1信号通路在2型糖尿病发生发展中的作用 被引量:7
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作者 张颖 郝进 《重庆医学》 CAS CSCD 北大核心 2012年第31期3333-3335,共3页
随着人们生活水平的提高,全身代谢性疾病逐渐成为影响人类生活质量的主要疾病之一。在近年的调查研究中发现,糖尿病的发生率较过去20年间呈数倍增加,尤其糖尿病并发症引起的死亡率较前大大提升。所以深入研究糖尿病的发生、发展机制... 随着人们生活水平的提高,全身代谢性疾病逐渐成为影响人类生活质量的主要疾病之一。在近年的调查研究中发现,糖尿病的发生率较过去20年间呈数倍增加,尤其糖尿病并发症引起的死亡率较前大大提升。所以深入研究糖尿病的发生、发展机制成为目前治疗糖尿病的关键。mTOR信号通路是雷帕霉素的靶分子,是丝氨酸/苏氨酸蛋白激酶,在感受营养信号、调节细胞生长和增殖中起关键性的作用。mTORComplexl-S6K1信号通路可受如生长因子、激素、能量信号等多种因素的调节,在糖尿病的发生、发展中起重要作用。本文将详细阐述mTORComplexl-S6K1信号通路在糖尿病的发生发展中的作用机制。 展开更多
关键词 糖尿病 2 MTOR complex1-S6K1 信号通路
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金属单质对Gd_(3)Al_(2)合金磁热效应的影响 被引量:3
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作者 生利英 《金属功能材料》 CAS 2022年第5期73-76,共4页
利用真空高频磁悬浮炉和热处理工艺制备了Gd_(3)Al_(2-x)Ga_(x)、Gd_(3-x)Mn_(x)Al_(1.8)Ga_(0.2)、Gd_(3-x)Mn_(x)Al_(2)和Gd_(3-x)Zn_(x)Al_(2)样品,研究了在1.5T磁场下,金属单质Ga、Mn和Zn对Gd_(3)Al_(2)合金磁热效应和结构的影响。... 利用真空高频磁悬浮炉和热处理工艺制备了Gd_(3)Al_(2-x)Ga_(x)、Gd_(3-x)Mn_(x)Al_(1.8)Ga_(0.2)、Gd_(3-x)Mn_(x)Al_(2)和Gd_(3-x)Zn_(x)Al_(2)样品,研究了在1.5T磁场下,金属单质Ga、Mn和Zn对Gd_(3)Al_(2)合金磁热效应和结构的影响。结果表明,微量金属单质不影响Gd_(3)Al_(2)合金的晶体结构;少量Ga替代Al可以提高Gd_(3)Al_(2)合金的绝热温变;在Gd_(3)Al_(1.8)Ga_(0.2)样品的基础上,添加Mn替代Gd,居里温度提高,绝热温变几乎保持不变;少量Mn和Zn替代Gd使Gd_(3)Al_(2)合金的居里温度提高到室温附近,降低最大绝热温变。 展开更多
关键词 Ga、Mn和Zn gd_(3)Al_(2)合金 绝热温变 居里温度 直接测量
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