Mg-14Li-1Al （LA141）, LA141-0.3Y, LA141-0.3Sr, and LA141-0.3Y-0.3Sr alloys were prepared in an induction furnace in the argon atmosphere. The microstructures of these alloys were investigated through scanning electro...Mg-14Li-1Al （LA141）, LA141-0.3Y, LA141-0.3Sr, and LA141-0.3Y-0.3Sr alloys were prepared in an induction furnace in the argon atmosphere. The microstructures of these alloys were investigated through scanning electron microscope （SEM）, X-ray diffractometer （XRD） and energy dispersive spectrometer （EDS）. The results show that yttrium and/or strontium additions produce a strong grain refining effect in LA141 alloy. The mean grain sizes of the alloys with addition of Y and/or Sr are reduced remarkably from 600 to 500, 260, 230 μm, respectively. Al 2 Y, Al 4 Sr and Mg 17 Sr 2 phases with different morphologies are verified and exist inside the grain or at the grain boundaries, thus possibly act as heterogeneous nucleation sites and pin up grain boundaries, which restrain the grain growth.展开更多
Al-5Ti-1B master alloy was added into Mg-14Li-1Al(LA141)alloy and then LA141 sheets were prepared by extrusion and cold rolling.The effect of the addition level of Al-5Ti-1B master alloy on the grain size of LA141 all...Al-5Ti-1B master alloy was added into Mg-14Li-1Al(LA141)alloy and then LA141 sheets were prepared by extrusion and cold rolling.The effect of the addition level of Al-5Ti-1B master alloy on the grain size of LA141 alloy was investigated as well as the effects of the total reduction of cold rolling and the annealing temperature on microstructure,mechanical properties and plastic formability of the LA141 sheets.The results show that the optimal addition level of Al-5Ti-1B master alloy into LA141 alloy is 1.25%(mass fraction)and LA141 alloy has the finest grains.With the increase of the total reduction of cold rolling,the grains of the as-rolled LA141 sheets were flattened gradually.A proper anneal temperature of 200℃ is obtained for the cold rolled LA141 sheets. Under this condition,microstructure of the LA141 sheets consists of fine and uniform equiaxed grains and has higher Erichsen cupping index(IE).展开更多
抗程序性细胞死亡受体-1(programmed cell death protein-1,PD-1)和抗程序性死亡受体配体-1(programmed cell death ligand-1,PD-L1)是目前广泛使用的免疫检查点抑制剂,在肿瘤免疫治疗方面取得了巨大的成就,但同时也导致免疫相关不良反...抗程序性细胞死亡受体-1(programmed cell death protein-1,PD-1)和抗程序性死亡受体配体-1(programmed cell death ligand-1,PD-L1)是目前广泛使用的免疫检查点抑制剂,在肿瘤免疫治疗方面取得了巨大的成就,但同时也导致免疫相关不良反应(immune-related adverse events,irAEs),严重者甚至会导致患者死亡。因此,明确irAEs的发生机制,提早预测irAEs非常重要。本文由细胞、免疫系统、个体水平层面对抗PD-1/PD-L1疗法致irAEs的发生机制进行了总结,并从一般临床特征、免疫细胞因素、细胞因子相关、基因表达结果等方面汇总了irAEs的预测指标。展开更多
目的:通过外源性注射趋化因子(C-X3-C基序)配体1(Fractalkine,CX3CL1)探索其对阿尔茨海默病(Alzheimer’sdisease,AD)小鼠神经元功能的影响及机制。方法:采用APP/PS1双转基因小鼠建立AD模型。将小鼠随机分为4组:对照组、AD模型组、AD+PB...目的:通过外源性注射趋化因子(C-X3-C基序)配体1(Fractalkine,CX3CL1)探索其对阿尔茨海默病(Alzheimer’sdisease,AD)小鼠神经元功能的影响及机制。方法:采用APP/PS1双转基因小鼠建立AD模型。将小鼠随机分为4组:对照组、AD模型组、AD+PBS溶剂组、AD+CX3CL1组。AD+CX3CL1组颅内给予CX3CL1。AD+PBS溶剂组注射等容积的PBS溶剂。采用旷场实验和Morris水迷宫测试小鼠认知行为,免疫荧光染色、TUNEL染色、尼氏染色、蛋白质印迹和RT-PCR技术对小鼠海马组织进行分析。结果:①AD小鼠接受CX3CL1注射后增加了移动距离,但没有显著差异(P=0.189);在水迷宫测试中,AD+CX3CL1组寻找水下平台的移动距离显著缩短(P=0.001);②AD模型组中GSDMD(Gasdermin D)蛋白和炎症相关蛋白表达显著升高(P<0.05),而CX3CL1注射能显著降低这些蛋白的表达水平(P<0.05);③AD模型组的尼氏体数量、突触相关蛋白25 kDa(synaptosomal-associated protein of 25 kDa,SNAP25)、突触后致密区蛋白95(post synaptic density protein 95,PSD95)和囊泡相关膜蛋白1(vesicle-associated membrane protein 1,VAMP1)表达水平显著降低,而CX3CL1组尼氏体数量(P=0.001)和SNAP25、PSD95、VAMP1蛋白的表达增加(P=0.043,P=0.026,P=0.003)。结论:外源性CX3CL1注射能够通过调节炎症因子和减少细胞焦亡来改善AD小鼠的神经元功能,保护神经元免受损伤。展开更多
The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explor...The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explored, characterized and tested by XRD, TEM, BET measurements. The sample sintered at 750 ℃ for 12 h had greater charge/discharge capacity, better cyclic stability under electric current charge/discharge cycle. The initial capacity reached 120 mA·h/g with the charge/discharge efficieney of 98% and maintained 115 mA·h/g after 50 cycles.展开更多
Ultrasonic vibration was introduced into the Mg-8Li-3A1 alloy melt during its solidification process. The microstructure, corrosion resistance and mechanical properties of the Mg-8Li-3A1 alloy under ultrasonic vibrati...Ultrasonic vibration was introduced into the Mg-8Li-3A1 alloy melt during its solidification process. The microstructure, corrosion resistance and mechanical properties of the Mg-8Li-3A1 alloy under ultrasonic vibration were investigated. The experiment results show that the morphology of a phase is modified from coarse rosette-like structure to fine globular one with the application of ultrasonic vibration. The fine globular structure is obtained especially when the power is 170 W, and the refining effect also gets better with prolonging the ultrasonic treatment time. The corrosion resistance of the alloy with 170 W of ultrasonic vibration for 90 s is improved apparently compared with the alloy without ultrasonic vibration. The mechanical properties of alloys with ultrasonic vibration are also both improved apparently. The tensile strength and elongation of alloy improve by 9.5% and 45.7%, respectively, with 170 W of ultrasonic treatment for 90 s.展开更多
基金Project(50725413)supported by the National Natural Science Foundation of ChinaProject(2010CSTC-BJLKR)supported by Chongqing Science and Technology Commission, ChinaProject(CDJXS10132203)supported by the Fundamental Research Funds for the Central Universities,China
文摘Mg-14Li-1Al （LA141）, LA141-0.3Y, LA141-0.3Sr, and LA141-0.3Y-0.3Sr alloys were prepared in an induction furnace in the argon atmosphere. The microstructures of these alloys were investigated through scanning electron microscope （SEM）, X-ray diffractometer （XRD） and energy dispersive spectrometer （EDS）. The results show that yttrium and/or strontium additions produce a strong grain refining effect in LA141 alloy. The mean grain sizes of the alloys with addition of Y and/or Sr are reduced remarkably from 600 to 500, 260, 230 μm, respectively. Al 2 Y, Al 4 Sr and Mg 17 Sr 2 phases with different morphologies are verified and exist inside the grain or at the grain boundaries, thus possibly act as heterogeneous nucleation sites and pin up grain boundaries, which restrain the grain growth.
文摘以改善冷轧Mg-Li系合金的变形能力为目的,系统研究了冷轧变形后的Mg-9Li-1Zn合金的退火热处理工艺,分析了退火温度和退火时间对合金组织和性能的影响.研究结果表明：Mg-9Li-1Zn合金适宜的退火温度为280~300℃,退火温度过高会出现晶粒长大,表面脱锂等现象.300℃退火60 min后,合金的维氏硬度值为426.7 MPa,充分完成再结晶软化的合金在后续冷轧时总变形率可达70%.合金的退火时间以保证α相的充分球化及组织的均匀化为准则,实验中确定的最佳退火制度为300℃保温60 min.
基金Project(50604020)supported by the National Natural Science Foundation of ChinaProject(2007CB613706)supported by the National Basic Research Program of ChinaProject(2009AA03Z507)supported by the National High-tech Research and Development Program of China
文摘Al-5Ti-1B master alloy was added into Mg-14Li-1Al(LA141)alloy and then LA141 sheets were prepared by extrusion and cold rolling.The effect of the addition level of Al-5Ti-1B master alloy on the grain size of LA141 alloy was investigated as well as the effects of the total reduction of cold rolling and the annealing temperature on microstructure,mechanical properties and plastic formability of the LA141 sheets.The results show that the optimal addition level of Al-5Ti-1B master alloy into LA141 alloy is 1.25%(mass fraction)and LA141 alloy has the finest grains.With the increase of the total reduction of cold rolling,the grains of the as-rolled LA141 sheets were flattened gradually.A proper anneal temperature of 200℃ is obtained for the cold rolled LA141 sheets. Under this condition,microstructure of the LA141 sheets consists of fine and uniform equiaxed grains and has higher Erichsen cupping index(IE).
文摘抗程序性细胞死亡受体-1(programmed cell death protein-1,PD-1)和抗程序性死亡受体配体-1(programmed cell death ligand-1,PD-L1)是目前广泛使用的免疫检查点抑制剂,在肿瘤免疫治疗方面取得了巨大的成就,但同时也导致免疫相关不良反应(immune-related adverse events,irAEs),严重者甚至会导致患者死亡。因此,明确irAEs的发生机制,提早预测irAEs非常重要。本文由细胞、免疫系统、个体水平层面对抗PD-1/PD-L1疗法致irAEs的发生机制进行了总结,并从一般临床特征、免疫细胞因素、细胞因子相关、基因表达结果等方面汇总了irAEs的预测指标。
文摘目的:通过外源性注射趋化因子(C-X3-C基序)配体1(Fractalkine,CX3CL1)探索其对阿尔茨海默病(Alzheimer’sdisease,AD)小鼠神经元功能的影响及机制。方法:采用APP/PS1双转基因小鼠建立AD模型。将小鼠随机分为4组:对照组、AD模型组、AD+PBS溶剂组、AD+CX3CL1组。AD+CX3CL1组颅内给予CX3CL1。AD+PBS溶剂组注射等容积的PBS溶剂。采用旷场实验和Morris水迷宫测试小鼠认知行为,免疫荧光染色、TUNEL染色、尼氏染色、蛋白质印迹和RT-PCR技术对小鼠海马组织进行分析。结果:①AD小鼠接受CX3CL1注射后增加了移动距离,但没有显著差异(P=0.189);在水迷宫测试中,AD+CX3CL1组寻找水下平台的移动距离显著缩短(P=0.001);②AD模型组中GSDMD(Gasdermin D)蛋白和炎症相关蛋白表达显著升高(P<0.05),而CX3CL1注射能显著降低这些蛋白的表达水平(P<0.05);③AD模型组的尼氏体数量、突触相关蛋白25 kDa(synaptosomal-associated protein of 25 kDa,SNAP25)、突触后致密区蛋白95(post synaptic density protein 95,PSD95)和囊泡相关膜蛋白1(vesicle-associated membrane protein 1,VAMP1)表达水平显著降低,而CX3CL1组尼氏体数量(P=0.001)和SNAP25、PSD95、VAMP1蛋白的表达增加(P=0.043,P=0.026,P=0.003)。结论:外源性CX3CL1注射能够通过调节炎症因子和减少细胞焦亡来改善AD小鼠的神经元功能,保护神经元免受损伤。
文摘The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explored, characterized and tested by XRD, TEM, BET measurements. The sample sintered at 750 ℃ for 12 h had greater charge/discharge capacity, better cyclic stability under electric current charge/discharge cycle. The initial capacity reached 120 mA·h/g with the charge/discharge efficieney of 98% and maintained 115 mA·h/g after 50 cycles.
基金Project(2009AA03Z525)supported by the High-tech Research and Development Program of ChinaProject(NCET-08-0080)supported by the Program of New Century Excellent Talents of the Ministry of Education of China+1 种基金Project(20082172)supported by the Natural Science Fund of Liaoning Province,ChinaProject(2009J21DW003)supported by the Science and Technology Fund of Dalian City,China
文摘Ultrasonic vibration was introduced into the Mg-8Li-3A1 alloy melt during its solidification process. The microstructure, corrosion resistance and mechanical properties of the Mg-8Li-3A1 alloy under ultrasonic vibration were investigated. The experiment results show that the morphology of a phase is modified from coarse rosette-like structure to fine globular one with the application of ultrasonic vibration. The fine globular structure is obtained especially when the power is 170 W, and the refining effect also gets better with prolonging the ultrasonic treatment time. The corrosion resistance of the alloy with 170 W of ultrasonic vibration for 90 s is improved apparently compared with the alloy without ultrasonic vibration. The mechanical properties of alloys with ultrasonic vibration are also both improved apparently. The tensile strength and elongation of alloy improve by 9.5% and 45.7%, respectively, with 170 W of ultrasonic treatment for 90 s.
