[Objective] The research aimed toexplore the method to obtain Hoxc8 pro- moter of Mongolian Sheep. [Method] Thermal asymmetric interlaced PCR was used to amplify the promoter sequence of Hoxc8 inMongolian Sheep. [Resu...[Objective] The research aimed toexplore the method to obtain Hoxc8 pro- moter of Mongolian Sheep. [Method] Thermal asymmetric interlaced PCR was used to amplify the promoter sequence of Hoxc8 inMongolian Sheep. [Result] The ob- tained sequence by usingthermal asymmetric interlaced PCRwas not ideal and the sequencing results were not matching to the known sequence. Though promoter se- quence of Hoxc8 in Mongolian Sheep was not obtained by thermal asymmetric in- terlaced PCR, but the results could provide references for the relevant studies in the future. [Conclusion] The research laid the foundation for further study on the methy- lation status Hoxc8 promoter in Mongolian Sheep.展开更多
Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysuppo...Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.展开更多
The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optima...The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optimal order error estimates are obtained in the broken energy norm. Finally, some numerical results are provided to verify the theoretical analysis.展开更多
为从宏、细观角度揭示常法向刚度(Constant Normal Stiffness,CNS)条件下锯齿状砂岩-混凝土结构面剪切机制,首先采用湖南大学自主改造的CNS岩石直剪仪开展3组砂岩-混凝土结构面室内剪切试验.在此基础上,采用刚性墙替代法建立与室内试验...为从宏、细观角度揭示常法向刚度(Constant Normal Stiffness,CNS)条件下锯齿状砂岩-混凝土结构面剪切机制,首先采用湖南大学自主改造的CNS岩石直剪仪开展3组砂岩-混凝土结构面室内剪切试验.在此基础上,采用刚性墙替代法建立与室内试验相应的离散元数值模型,并引入3个显式运动学方程控制砂岩试样运动轨迹从而实现CNS条件加载,将数值模拟与试验结果对比验证了模型的合理性.随后,开展16个工况的数值剪切试验,通过观察剪切裂纹扩展和力链演化形态,从细观角度揭示结构面破坏模式和荷载传递机制,并从宏观角度分析锯齿几何尺寸(半波长λ、起伏角θ)和加载边界条件(初始法向应力σn0、法向刚度K)对剪切强度和法向膨胀的影响.结果表明:剪切裂纹按照“平稳增加—急剧增加—增幅减小”的发展趋势由结构面区域逐渐向岩石内部扩展,结构面破坏模式随起伏角的增大由滑移磨损向剪断破坏过渡,剪切强度随λ、θ、σn0和K的增加呈指数函数型增加.展开更多
This paper investigates the effects of substitution of Si for Ga on the martensitic transformation behaviours in Ni-Fe-Ga alloys by using optical metallographic microscope and differential scanning calorimetry （DSC）...This paper investigates the effects of substitution of Si for Ga on the martensitic transformation behaviours in Ni-Fe-Ga alloys by using optical metallographic microscope and differential scanning calorimetry （DSC） methods. The structure type of Ni55.5Fe18Ga26.5-xSix alloys is determined by x-ray diffraction （XRD）, and the XRD patterns show the microstructure of Ni-Fe-Ga-Si alloys transformed from body-centred tetragonal martensite （with Si content x = 0） to body-centred cubic austenite （with x = 2） at room temperature. The martensitic transformation temperatures of the Ni55.sFelsGa26.5-xSi~ alloys decrease almost linearly with increasing Si content in the Si content range of x _~ 3. Thermal treatment also plays an important role on martensitic transformation temperatures in the Ni-Fe-Ga^Si alloy. The valence electronic concentrations, size factor, L21 degree of order and strength of parent phase influence the martensitic transformation temperatures of the Ni-Fe-Ga-Si alloys. An understanding of the relationship between martensitic transformation temperatures and Si content will be significant for designing an appropriate Ni-Fe-Ga-Si alloy for a specific application at a given temperature.展开更多
本文针对3D堆叠磁随机存储器(Magnetic Random Access Memory,MRAM)的热学分析问题,在有限元法和热阻网络法的基础上,提出了一种局部等效法,可高精度并且快速地分析3D堆叠MRAM的热学分布.与有限元法相比,该方法使用直观方便,克服了有限...本文针对3D堆叠磁随机存储器(Magnetic Random Access Memory,MRAM)的热学分析问题,在有限元法和热阻网络法的基础上,提出了一种局部等效法,可高精度并且快速地分析3D堆叠MRAM的热学分布.与有限元法相比,该方法使用直观方便,克服了有限元法建模与求解复杂耗时的问题;与热阻网络法相比,局部等效法具有保持较高精度的特点,解决了热阻网络法针对带夹层和硅通孔(Through Silicon Via,TSV)的复杂封装问题时存在较大误差的问题.对比结果表明,使用本文提出的方法得出的各叠层的上表面温度误差均小于0.05℃,精度与有限元法一致,并且更便捷高效.同时对应的建模结构简单,避免了热阻网络法将含铜柱的夹层和含铜柱的硅层分开考虑的不准确性.本文的研究可为未来多层3D堆叠MRAM热学特性相关的设计与分析提供指导.展开更多
Porous ZIF-7 with the sodalite （SOD） cage structure （ZIF, Zeolitic imidazolate framework） were synthesized by the solvothermal method. Synthesized material was characterized by powder X-ray diffraction （PXRD）, t...Porous ZIF-7 with the sodalite （SOD） cage structure （ZIF, Zeolitic imidazolate framework） were synthesized by the solvothermal method. Synthesized material was characterized by powder X-ray diffraction （PXRD）, thermal gravity （TG）, scanning electron micro- scopy （SEM） and Na adsorption analysis. ZIF-8 with the SOD structure and a littl larger pore window was synthesized in a similar way and was characterized for comparisons. Thermal stability and structural stability of ZIF-7 were tested through PXRD analysis, and the capability of the material for CO2 capture from simulated flue gas was investigated through physical adsorption method. The results showed that CO： adsorption capacity on ZIF-7 was about 48 mL. gl while the capacity on ZIF-8 was about 18mg.g-1 （at 12C and 0.98 P/Po relative pressure）. Furthermore, the impact of flue gas components on adsorption capacity of ZIF-7 and the selectivity of CO2 against N2 on ZIF-7 was also investigated in this work展开更多
基金Supported by the Supporting Program of the"Eleventh Five-year Plan"for Sci&Tech Research of China(2006BDA13B08)National Natural Science Foundation of China(30960245)~~
文摘[Objective] The research aimed toexplore the method to obtain Hoxc8 pro- moter of Mongolian Sheep. [Method] Thermal asymmetric interlaced PCR was used to amplify the promoter sequence of Hoxc8 inMongolian Sheep. [Result] The ob- tained sequence by usingthermal asymmetric interlaced PCRwas not ideal and the sequencing results were not matching to the known sequence. Though promoter se- quence of Hoxc8 in Mongolian Sheep was not obtained by thermal asymmetric in- terlaced PCR, but the results could provide references for the relevant studies in the future. [Conclusion] The research laid the foundation for further study on the methy- lation status Hoxc8 promoter in Mongolian Sheep.
文摘Based on vibration analysis, single-layered graphene sheet （SLGS） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference.
基金Project supported by the National Natural Science Foundation of China(No.11271340)
文摘The lowest order Pl-nonconforming triangular finite element method （FEM） for elliptic and parabolic interface problems is investigated. Under some reasonable regularity assumptions on the exact solutions, the optimal order error estimates are obtained in the broken energy norm. Finally, some numerical results are provided to verify the theoretical analysis.
文摘为从宏、细观角度揭示常法向刚度(Constant Normal Stiffness,CNS)条件下锯齿状砂岩-混凝土结构面剪切机制,首先采用湖南大学自主改造的CNS岩石直剪仪开展3组砂岩-混凝土结构面室内剪切试验.在此基础上,采用刚性墙替代法建立与室内试验相应的离散元数值模型,并引入3个显式运动学方程控制砂岩试样运动轨迹从而实现CNS条件加载,将数值模拟与试验结果对比验证了模型的合理性.随后,开展16个工况的数值剪切试验,通过观察剪切裂纹扩展和力链演化形态,从细观角度揭示结构面破坏模式和荷载传递机制,并从宏观角度分析锯齿几何尺寸(半波长λ、起伏角θ)和加载边界条件(初始法向应力σn0、法向刚度K)对剪切强度和法向膨胀的影响.结果表明:剪切裂纹按照“平稳增加—急剧增加—增幅减小”的发展趋势由结构面区域逐渐向岩石内部扩展,结构面破坏模式随起伏角的增大由滑移磨损向剪断破坏过渡,剪切强度随λ、θ、σn0和K的增加呈指数函数型增加.
基金supported by the National Natural Science Foundation of China (Grant No. 10976007)the Fundamental Research Funds for the Central Universities (Grant Nos. ZYGX2009J046 and ZYGX2009X007)Royal Academy of Engineering-Research Exchanges with China and India Awards in UK
文摘This paper investigates the effects of substitution of Si for Ga on the martensitic transformation behaviours in Ni-Fe-Ga alloys by using optical metallographic microscope and differential scanning calorimetry （DSC） methods. The structure type of Ni55.5Fe18Ga26.5-xSix alloys is determined by x-ray diffraction （XRD）, and the XRD patterns show the microstructure of Ni-Fe-Ga-Si alloys transformed from body-centred tetragonal martensite （with Si content x = 0） to body-centred cubic austenite （with x = 2） at room temperature. The martensitic transformation temperatures of the Ni55.sFelsGa26.5-xSi~ alloys decrease almost linearly with increasing Si content in the Si content range of x _~ 3. Thermal treatment also plays an important role on martensitic transformation temperatures in the Ni-Fe-Ga^Si alloy. The valence electronic concentrations, size factor, L21 degree of order and strength of parent phase influence the martensitic transformation temperatures of the Ni-Fe-Ga-Si alloys. An understanding of the relationship between martensitic transformation temperatures and Si content will be significant for designing an appropriate Ni-Fe-Ga-Si alloy for a specific application at a given temperature.
文摘Porous ZIF-7 with the sodalite （SOD） cage structure （ZIF, Zeolitic imidazolate framework） were synthesized by the solvothermal method. Synthesized material was characterized by powder X-ray diffraction （PXRD）, thermal gravity （TG）, scanning electron micro- scopy （SEM） and Na adsorption analysis. ZIF-8 with the SOD structure and a littl larger pore window was synthesized in a similar way and was characterized for comparisons. Thermal stability and structural stability of ZIF-7 were tested through PXRD analysis, and the capability of the material for CO2 capture from simulated flue gas was investigated through physical adsorption method. The results showed that CO： adsorption capacity on ZIF-7 was about 48 mL. gl while the capacity on ZIF-8 was about 18mg.g-1 （at 12C and 0.98 P/Po relative pressure）. Furthermore, the impact of flue gas components on adsorption capacity of ZIF-7 and the selectivity of CO2 against N2 on ZIF-7 was also investigated in this work
