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B位Ti^(4+)掺杂对Gd_(2)(Zr_(0.7)Ce_0.3)_(2)O_(7)陶瓷材料抗熔盐腐蚀性能的影响
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作者 燕子厚 欧阳锐 +4 位作者 谢敏 张永和 宋希文 牟仁德 安胜利 《腐蚀与防护》 北大核心 2026年第2期42-48,共7页
采用固相反应法制备了Gd_(2)(Zr_(0.7)Ce_(0.3-x)Ti_(x))_(2)O_(7)(x=0~0.3)陶瓷材料,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和维氏硬度计等表征和测试了陶瓷材料在V_(2)O_(5)+Na_(2)SO_(4)熔盐腐蚀前后的物相组成、微观形貌及断... 采用固相反应法制备了Gd_(2)(Zr_(0.7)Ce_(0.3-x)Ti_(x))_(2)O_(7)(x=0~0.3)陶瓷材料,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和维氏硬度计等表征和测试了陶瓷材料在V_(2)O_(5)+Na_(2)SO_(4)熔盐腐蚀前后的物相组成、微观形貌及断裂韧度。结果表明:Ti^(4+)掺杂后该陶瓷材料的腐蚀产物种类没有发生变化,均为GdVO_(4)与单斜相的氧化锆(m-ZrO_(2)),但Ti^(4+)的掺杂可在一定程度上抑制腐蚀产物生成,提高腐蚀后陶瓷材料的断裂韧度。 展开更多
关键词 热障涂层 gd_(2)(Zr_(0.7)Ce_0.3)_(2)O_(7)陶瓷材料 断裂韧度 熔盐腐蚀
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Microstructure and Thermal Properties of MoSi_(2)and Gd_(2)Zr_(2)O_(7)Composite Coatings on Mo-Re Alloy
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作者 Zhang Chong Wang Xin +3 位作者 Xu Hailong Li Yanchao Ma Tongxiang Wang Shaopeng 《稀有金属材料与工程》 北大核心 2026年第2期315-321,共7页
Dual-layer thermal barrier coatings(TBCs)with ultrahigh temperature resistance were prepared on the surface of molybdenum-rhenium alloy hot-end components.The preparation of the MoSi_(2)-Gd_(2)Zr_(2)O_(7)dual-layer TB... Dual-layer thermal barrier coatings(TBCs)with ultrahigh temperature resistance were prepared on the surface of molybdenum-rhenium alloy hot-end components.The preparation of the MoSi_(2)-Gd_(2)Zr_(2)O_(7)dual-layer TBCs was designed based on the coefficient of thermal expansion and the coating functionality,and it was completed using atmospheric plasma spraying technique.The microstructure,mechanical properties,and thermal properties were analyzed.Results indicate that the adhesion of the prepared dual-layer composite TBCs is excellent,and no noticeable cracks appear at the interface.Compared with the MoSi_(2)coating with a low fracture toughness(0.88 MPa·m^(1/2)),the Gd_(2)Zr_(2)O_(7)coating exhibits higher fracture toughness(1.74 MPa·m^(1/2))and stronger resistance to crack propagation.The prepared MoSi_(2)-Gd_(2)Zr_(2)O_(7)composite coatings have a high porosity(39%),low thermal conductivity(1.020 W·(m·K)^(−1),1200℃),and low thermal diffusivity(0.249 mm^(2)/s,1200℃).Additionally,they possess a high oxygen-vacancy concentration,which ensures excellent insulation performance. 展开更多
关键词 MoSi_(2)-gd_(2)Zr_(2)O_(7)coating molybdenum-rhenium alloy TBCS thermal insulation performance
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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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Star-shaped Block Copolymers of Poly-2-alkyl-5,6-dihydrooxazines:Synthesis,Conformational Characteristics,Thermoresponsiveness and Complexation with Curcumin
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作者 Tatyana U.Kirila Serafim V.Rodchenko +2 位作者 Nina D.Kozina Andrey V.Tenkovtsev Alexander P.Filippov 《Chinese Journal of Polymer Science》 2026年第2期423-436,I0012,共15页
Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cat... Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cationic ring-opening polymerization.The ratio of blocks,the order of their attachment to the core,and arm length were varied.Conformation of synthesized stars was determined by methods of molecular hydrodynamics and optics.It has been shown that star-shaped molecules were characterized by high intramolecular density,and the arm folding increased with their lengthening.The influence of the structure of block copolymers and their molar mass on the critical micelle concentration has been established.Complexes of synthesized star-shaped block copolymers with curcumin were obtained and the efficient binding of curcumin to polymer molecules was demonstrated.The behavior of the aqueous solutions of the prepared polymer stars and their complexes with curcumin was investigated by light scattering and turbidimetry methods.The influence of the structure and molar mass of star polymers on their thermoresponsiveness and the phase separation temperatures in aqueous solutions was analyzed.A slight increase in the phase separation temperature was found on passage from polymer solutions to solutions of polymer complexes with hydrophobic curcumin. 展开更多
关键词 Thermoresponsive star-shaped polymers Block copolymer of poly-2-alkyl-5 6-dihydrooxazine Aqueous solutions complex of polymer with curcumin Phase separation
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Combinational Inhibition of the eIF4F Complex,AKT1,and EZH2 Enhances Anticancer Effects in BRAFV600E Mutant A375 Melanoma Cells
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作者 Yuanxin Miao Fengyun Hao Sae Hwi Ki 《Oncology Research》 2026年第3期502-522,共21页
Objectives:The eukaryotic initiation factor 4F(eIF4F)translation initiation complex inhibitors(eIF4Fi)were recently found to hyperactivate extracellular signal-regulated kinases 1/2(ERK1/2)signals,which contribute to ... Objectives:The eukaryotic initiation factor 4F(eIF4F)translation initiation complex inhibitors(eIF4Fi)were recently found to hyperactivate extracellular signal-regulated kinases 1/2(ERK1/2)signals,which contribute to acquired resistance to BRAF(B-Raf proto-oncogene,serine/threonine kinase)inhibitors in melanoma.This present study aims to elucidate how to overcome the resistance of the eIF4Fi in BRAFV600E mutant melanoma cells and explore the underlying mechanisms.Methods:Melanoma A375(vemurafenib[VEM]-sensitive)and A375R(VEM-resistant)cells were exposed to eIF4Fi RocA at varying doses and durations in vitro.We investigated the impact of RocA on the activity of ERK1/2,AKT serine/threonine kinase 1(AKT1),eIF4E,and enhancer of zeste homolog 2(EZH2).We then examined the impact of RocA on pro-apoptotic BH3-only proteins and proliferative proteins.We subsequently determined the effect of combined eIF4Fi,AKT1 inhibitor,EZH2 inhibitor or VEM on tumor growth in vitro and in vivo.Results:RocA inhibited proliferation and induced apoptosis in A375 cells,but inhibited proliferation in A375R cells.RocA rapidly reactivated ERK1/2 at 3 h and returned to baseline levels at 48 h.However,eIF4E and AKT1 activation began at 12 h and peaked at 48 h.ERK1/2 positively regulated EZH2 and EZH2-dependent expression of c-Fos and EGR1,while AKT1 negatively regulated c-Myc,c-Jun,and BMF,but positively regulated eIF4E.RocA downregulated ERK1/2(or EZH2,AKT1,and eIF4E)independent bcl-2 and Mcl-1 expression.AKT1i enhanced RocA-induced cell apoptosis,while EZH2i reduced RocA-induced cell proliferation.Combined CR-1-31-B,EZH2i,and AKT1i effectively overcame resistance to RocA and VEM resistance both in vitro and in vivo.Conclusion:The eIF4F complex inhibitor reactivates ERK1/2-EZH2 and AKT1 signaling pathways,resulting in resistance to both eIF4Fi and VEM.Combined administration of an eIF4Fi with EZH2 and AKT1 inhibitors effectively enhances sensitivity to both eIF4F complex and BRAF inhibitors. 展开更多
关键词 Melanoma B-raf proto-oncogene serine/threonine kinase-inhibitor eukaryotic initiation factor 4F complex inhibitor extracellular signal-regulated kinases 1/2 enhancer of zeste homolog 2 AKT serine/threonine kinase 1 Bcl-2 modifying factor
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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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TRAPPC2基因变异致X-连锁迟发性脊椎骨骺发育不良的3个家系分析
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作者 王亚琼 应令雯 +5 位作者 陈瑶 姚如恩 娄丹 卢亚亚 李娟 王秀敏 《检验医学》 2026年第2期133-143,共11页
目的探讨转运蛋白复合体亚单位2(TRAPPC2)基因变异致X-连锁迟发性脊椎骨骺发育不良(SEDT)家系的临床表型和遗传学特点。方法选取2019年1月—2024年9月上海交通大学医学院附属上海儿童医学中心确诊的3个X-连锁SEDT家系。收集家系成员的... 目的探讨转运蛋白复合体亚单位2(TRAPPC2)基因变异致X-连锁迟发性脊椎骨骺发育不良(SEDT)家系的临床表型和遗传学特点。方法选取2019年1月—2024年9月上海交通大学医学院附属上海儿童医学中心确诊的3个X-连锁SEDT家系。收集家系成员的临床资料,并进行全外显子组测序(WES)和生物信息学分析,采用Sanger测序对可疑突变进行验证。参照美国医学遗传学与基因组学学会(ACMG)相关指南对变异进行评级。结果3个家系的先证者均为男性,均因生长迟缓就诊,脊柱X线片示椎体扁平、前部上下缘凹陷、中后部呈驼峰样突起改变。家系1和家系2的先证者TRAPPC2基因(NM_001011658.4)均存在半合子变异c.271_275del(p.Gln91Argfs*9),为致病性变异;先证者母亲该位点均存在杂合突变,父亲未检测到该突变。家系3先证者TRAPPC2基因(NM_001011658.4)存在半合子变异c.191_192delTG(p.Val64Glyfs*24),其父母未发现该位点存在任何突变,考虑为假定新发变异;行重组人生长激素(rhGH)治疗,疗效欠佳。结论TRAPPC2基因变异所致的SEDT呈晚发性、进行性特征,可致不成比例的身材矮小和关节过早退化。对于青少年时期起病的患儿,若合并上下部量异常或指尖距不匹配,需警惕SEDT。WES检测有助于明确病因。 展开更多
关键词 转运蛋白复合体亚单位2基因 缺失突变 X-连锁迟发性脊椎骨骺发育不良
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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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脑脊液AP2与阿尔茨海默病病理及认知功能的相关性研究
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作者 李仁贵 陈雨豪 +5 位作者 盛泽虎 冉明 王静怡 陈茗 汪克建 余维华 《阿尔茨海默病及相关病杂志》 2026年第1期10-18,共9页
目的:探讨阿尔茨海默病(AD)患者脑脊液(CSF)中衔接蛋白复合物2(AP2)的水平与AD病理、脑结构变化及认知功能的关联。方法:本研究纳入了来自AD神经影像学倡议数据库的138例AD患者、403例轻度认知障碍患者(MCI)和167名认知功能正常者(CN),... 目的:探讨阿尔茨海默病(AD)患者脑脊液(CSF)中衔接蛋白复合物2(AP2)的水平与AD病理、脑结构变化及认知功能的关联。方法:本研究纳入了来自AD神经影像学倡议数据库的138例AD患者、403例轻度认知障碍患者(MCI)和167名认知功能正常者(CN),测量其CSF中AP2(α2和β1亚基)水平;收集基线及五年随访期间的AD核心生物标志物浓度,数据包括β-淀粉样蛋白1-42(Aβ_(42))、总tau蛋白(t-Tau)和磷酸化tau蛋白(p-Tau181);脑结构数据包括脑室体积、海马体积和内嗅皮层厚度;认知功能评分数据包括简易智力状态检查量表(MMSE)、临床痴呆评分总和量表(CDRSB)。采用单因素协方差分析、多元线性回归模型和线性混合效应模型进行统计分析。结果:在基线时,CSF中AP2水平在CN组、MCI组和AD组间无显著差异,但在载脂蛋白(APOE)ε4携带者中均显著升高。随着年龄的增长,CSF中AP2水平呈上升趋势,与AD病理进展一致。CSF中AP2水平升高与CSF Aβ_(42)、t-Tau、p-Tau181浓度升高以及脑室体积更小呈显著相关,尤其在CN、MCI阶段更为显著。CSF AP2β1与CDRSB呈负相关,与海马体积和内嗅皮层厚度呈正相关。此外,CSF中AP2影响纵向脑结构及认知的改变,尤其在非AD组中更为显著。结论:CSF中AP2可能参与早期Aβ和Tau病理,并与脑室体积、海马体积、内嗅皮层厚度和认知的改变密切相关,尤其在AD的前临床和前驱阶段。 展开更多
关键词 阿尔茨海默病 衔接蛋白复合物2 Tau病理 网格蛋白 内吞作用
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复杂小断块油藏CO_(2)异步注采实验及技术政策优化
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作者 凌定坤 蒋庞露 +3 位作者 王智林 陈龙兴 杨睿 陆佳昊 《复杂油气藏》 2026年第1期17-23,共7页
针对复杂断块油藏受限于含油面积及形态,常规气驱方式难以实现有效波及动用的难题,提出了CO_(2)异步注采驱替方式以提升其波及效果及最终采收率。首先通过研发复杂断块油藏物理模型,对比了其与常规岩心模型下不同驱替方式的采收率,明确... 针对复杂断块油藏受限于含油面积及形态,常规气驱方式难以实现有效波及动用的难题,提出了CO_(2)异步注采驱替方式以提升其波及效果及最终采收率。首先通过研发复杂断块油藏物理模型,对比了其与常规岩心模型下不同驱替方式的采收率,明确了异步注采提升复杂断块油藏采收率幅度及其原因,且确定了该驱替方式下最佳注入压力和注入量。其次,基于Q4断块真实模型进行数值模拟研究,优化了在异步注采方式下的注气井网、注气量、注气速度、焖井时间等技术参数。结果表明:异步注采驱替方式通过动用常规气驱未动用的“角隅油”,可提高复杂断块油藏采收率11.09个百分点;注气速度对最终采收率影响较大,最佳注气速度为3.96PV/a;注入量及焖井时间对最终采收率有一定影响,最佳注入量及焖井时间分别为1.5PV和30d;在以上参数条件下可实现Q4断块换油率提高至0.39,采收率为22.36%。研究结果为复杂小断块油藏采收率的大幅提升提供新的技术手段及参考借鉴。 展开更多
关键词 复杂断块油藏 角隅油 CO_(2)驱 异步注采 换油率 采收率
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