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101.
利用静电力显微镜(EFM)研究了二相材料不同区域的介电特性. 制备了高定向石墨/聚乙烯、云母/聚乙烯等层叠状二相材料复合物, 在EFM相位检测模式下观测二相材料过渡界面处, 可以发现二相材料中介电常数较大的材料会引起较大的相位滞后角Δθ该相位滞后角正切值tan(Δθ) 与探针电压VEFM存在二次函数关系, 且函数二次项系数与样品的介电常数存在增函数关系, 进而可在微纳米尺度下区分不同微区域内材料的介电常数差异. 研究表明EFM 可用于对材料介电特性的微纳米尺度测量, 这对分析复合材料二相界面区域特性有积极意义. 相似文献
102.
基因测序技术极大地推动了生物学和医学研究的发展. 结合了焦磷酸测序 原理及阵列式微反应池芯片的高通量测序仪在从头测序和宏基因组测序方面有着不可替代的作用. 本文首次提出并研制了一种基于SU8聚合物的基因测序芯片. 选择了高传输效率、 低耦合损耗的光纤面板作为基片, 通过改善SU8均匀性及释放应力, 在光纤面板上成功制备出百万数量级阵列式微反应池; 设计并制作侧壁镀膜装置, 实现了SU8阵列式微反应池侧壁选择性光学薄膜蒸镀, 有效地提高了微反应池的光学隔离度, 将相邻微反应池之间的光串扰率平均值从25%降低到了1%, 满足了高通量焦磷酸测序对测序芯片独立并行传输弱光信号的要求. 基于SU8聚合物的基因测序芯片制备工艺简单、成本低廉, 具有良好的应用前景.
关键词:
DNA测序
SU8
微反应池
光纤面板 相似文献
103.
基于密度泛函理论下的第一性原理平面波超软赝势方法,研究了单层GaN、g-C3N4、GaN/g-C3N4异质结及3种氮缺陷GaN/g-C3N4-VXN (X=1、2、3)异质结的稳定性、电子结构、功函数及光学性能。计算结果表明,GaN/g-C3N4异质结体系晶格失配率极低(0.8%),属于完全共格。与单层g-C3N4相比,GaN/g-C3N4和GaN/g-C3N4-VXN (X=1、2、3)异质结的导带向低能方向偏移,价带上移,从而导致带隙减小,且态密度均显示出轨道杂化现象。GaN/g-C3N4和GaN/g-C3N4-VXN (X=1、2、3)异质结在界面处均形成了电势差,在其内部形成了从g-C3N4层指向GaN层的内置电场。GaN/g-C3N4-V1N异质结的界面电势差值最大且红移现象最为明显,表明GaN/g-C3N4-V1N异质结相较其他2个N缺陷异质结光学性能最好。氮缺陷的引入在不同程度上提高了GaN/g-C3N4异质结在红外光区域的光吸收能力。 相似文献
104.
In this article, we primarily review the time-resolved imaging of THz phonon polariton, which is generated by femtosecond laser in ferroelectric crystal. We pay more attention to the imaging in thin crystal, which can be used as an integration platform for terahertz-optics or terahertz-electrics. The imaging techniques, which can get quantitatively in-focus time-resolved images, are introduced in more detail. They have made enormous progress in recent years, and are powerful tools for the research of phonon polariton, optics, and THz wave. We also briefly introduce the generation principle and general propagation properties of THz phonon polariton. 相似文献
105.
106.
We investigate heat diffusion across a local strong stochastic magnetic field by using eleven low-m perturbed magnetic islands. A maximum stochasticity of 38.82 between two neighboring rational surfaces is attained. The correlation between the effective radial heat conductivity xτ and the ratio of the parallel heat diffusion coefficient to the perpendicular coefficient, χⅡ/χ⊥, is numerically studied and compared with earlier work. 相似文献
107.
Recent research shows that fermions tunnelling can result in correct Hawking temperature of a black hole. In this letter, choosing a set of appropriate matrices γμ, we attempt to study Hawking radiation of Dirac particles across the horizons of the GHS and non-extremal five-dimensional D1–D5 black holes in string theory by using fermions tunnelling method. Finally, the expected Hawking temperatures of the GHS and non-extremal D1–D5 black holes are correctly recovered. 相似文献
108.
TAN Jia-Jin CHENG Yan ZHU Wen-Jun GOU Qing-Quan 《理论物理通讯》2008,50(7):220-226
The lattice parameters, bulk modulus, phase transition pressure, and temperature dependencies of the elastic constants cij of CdSe are investigated by using the Cambridge Serial Total Energy Package (CASTEP) program in the frame of Density Functional Theory (DFT). It is found that the phase transitions from the ZB structure to the RS structure and from WZ structure to RS structure are 2.2 GPa and 2.8 GPa, respectively. Our results agree well with the available experimental data and other theoretical results. The aggregate elastic modulus (B, G, E, A ), the Poisson's ratio (v), the Griuneisen parameter (γ), the Debye temperature θD on pressure and temperature are also successfully obtained. 相似文献
109.
CHENG Yan TU Ya-Jing ZENG Zhao-Yi GOU Qing-Quan 《理论物理通讯》2008,50(12):1443-1448
Shell model molecular dynamic simulation with interatomic pair potential is utilized to investigate the elastic and thermodynamic properties of gallium nitride with hexagonal wurtzite structure (w-GaN) at high pressure. The calculated elastic constants Cij at zero pressure and 300 K agree well with the experimental data and other calculated values. Meanwhile, the dependences of the relative volume V/Vo, elastic constants Cij, entropy S, enthalpy H, and heat capacities Cv and Up on pressure are successfully obtained. From the elastic constants obtained, we also calculate the shear modulus G, bulk modulus B, Young's modulus E, Poisson's ratio v, Debye temperature ΘD, and shear anisotropic factor Ashear on pressures. 相似文献
110.
The formation mechanism and the binding energy the body—centred regular tetrahedral structure of He5^+
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We propose the formation mechanism of the body-centred regular tetrahedral structure of the He5^ cluster,The total energy curve for this structure has been calculated by using a modified arrangement channel quantum mechanics method.The result shows that a minimal energy of -13.9106 a.u.occurs at a separation of 1.14a0 between the nucleus at the centre and nuclei at the apexes.Therefore we obtain the binding energy of 0.5202a .u.for this structure.This means that the He5^ cluster may be stable with a high binding energy in a body-centred regular tetrahedral structure. 相似文献