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101.
Cs原子磁力仪共振谱线宽度的研究 总被引:1,自引:0,他引:1
介绍了Cs原子无自旋交换弛豫磁力仪(Cs-SERFM)的工作原理;分析了Cs泡温度105℃条件下,缓冲气体He的压强对Cs原子横向弛豫及线宽的影响,给出了惰性气体He的最佳压强为350×133.3 Pa;讨论了共振谱线的宽度与温度之间的关系,在105℃时Cs-SERFM谱线宽度仅为3.7 Hz。 相似文献
102.
Mihaela Nedelcu Mohammad S. M. Saifullah David G. Hasko Arang Jang David Anderson Wilhelm T. S. Huck Geraint A. C. Jones Mark E. Welland Dae Joon Kang Ullrich Steiner 《Advanced functional materials》2010,20(14):2317-2323
The fabrication of very narrow metal lines by the lift‐off technique, especially below sub‐10 nm, is challenging due to thinner resist requirements in order to achieve the lithographic resolution. At such small length scales, when the grain size becomes comparable with the line‐width, the built‐in stress in the metal film can cause a break to occur at a grain boundary. Moreover, the line‐width roughness (LWR) from the patterned resist can result in deposited metal lines with a very high LWR, leading to an adverse change in device characteristics. Here a new approach that is not based on the lift‐off technique but rather on low temperature hydrogen reduction of electron‐beam patterned metal naphthenates is demonstrated. This not only enables the fabrication of sub‐10 nm metal lines of good integrity, but also of low LWR, below the limit of 3.2 nm discussed in the International Technology Roadmap for Semiconductors. Using this method, sub‐10 nm nickel wires are obtained by reducing patterned nickel naphthenate lines in a hydrogen‐rich atmosphere at 500 °C for 1 h. The LWR (i.e., 3 σLWR) of these nickel nanolines was found to be 2.9 nm. The technique is general and is likely to be suitable for fabrication of nanostructures of most commonly used metals (and their alloys), such as iron, cobalt, nickel, copper, tungsten, molybdenum, and so on, from their respective metal–organic compounds. 相似文献
103.
On the Asymmetry for Convex Domains of Constant Width 总被引:1,自引:0,他引:1
The extremal convex bodies of constant width for the Minkowski measure of asymmetry are discussed. A result, similar to that of H. Groemer's and of H. Lu's, is obtained, which states that, for the Minkowski measure of asymmetry, the most asymmetric convex domains of constant width in R2 are Reuleaux triangles. 相似文献
104.
基于平面波展开法的二维光子晶体表面模式研究 总被引:1,自引:1,他引:1
采用平面波展开法研究了四种二维光子晶体结构(圆柱介质柱四方晶格、圆柱介质柱三角晶格、正方介质柱四方晶格、正方介质柱三角晶格)的带隙宽度随介质柱尺寸变化的关系.使用平面波展开法计算常规晶格和表面缺陷晶格的模式并进行结果叠加,研究了各结构的二维光子晶体在带隙宽度最大时的表面模式.结果表明,同种晶格的光子晶体带隙宽度随着介质柱的尺寸增大呈先增后减趋势,存在最大值.随着表面介质柱尺寸的增加,四种晶格表面模式曲线均呈下降趋势.四方晶格光子晶体与三角晶格相比,表面介质柱尺寸的变化范围更大,但能获取表面模式频率范围较小. 相似文献
105.
106.
107.
基于广义惠更斯-菲涅耳原理,采用Rytov相位结构函数二次近似和硬边窗口函数的复高斯展开法,推导了受光阑限制的多色高斯-谢尔模型(GSM)光束在大气湍流中的二阶矩束宽公式。研究表明:二阶矩束宽随着大气湍流折射率结构常数、源光谱带宽和光束传输距离的增加而增大,随着光束截断参数和光束相干参数的增加而减小;并且,当源光谱带宽越大、光束截断参数和光束相干参数越小,则湍流对受光阑限制的多色GSM光束扩展的影响就越小。关键词: 相似文献
108.
P. V. Dhanaraj N. P. Rajesh P. Ramasamy M. Jeyaprakasan C. K. Mahadevan G. Bhagavannarayana 《Crystal Research and Technology》2009,44(1):54-60
Potassium Acetate (CH3COOK) and Potassium Citrate (K3C6H5O7) as new additives were added into the potassium dihydrogen phosphate (KDP) solutions in different molar ratios. The metastable zone width and induction period with and without these additives were determined and compared. Dielectric measurements on pure and doped KDP crystals at various temperatures ranging from 313 to 423 K were carried out by the conventional parallel plate capacitor method which results low dielectric constant value dielectrics in doped crystals. The high resolution XRD studies show that CH3COOK doped KDP crystal and K3C6H5O7 doped KDP crystal do not contain any internal structural grain boundaries and indicates that the crystalline perfection is very good. Moreover, the addition of these potassium additives improves the quality of the crystal and yields highly transparent crystals with well defined features. The effect of additives on the growth, nucleation kinetics, structural, NLO and optical properties has been investigated. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
109.
讨论了半导体浪涌保护器件的基区宽度,着重分析了基区宽度与开通电压、静电电容、浪涌能力的关系,指出控制基区宽度,可有效地提高器件的浪涌能力,降低静电电容和开通电压 相似文献
110.
Absorption spectra of the gas phase and adsorbed D2О in the silica aerogel with nanoscale pores were investigated in 3700–5400 cm?1 range using dynamic registration with Fourier Transform spectrometer IFS-125M. Two types of sample with pores of 60 nm wide – the nitrogen gas-treated and untreated aerogels – were examined. The surface treatment of the sample changes noticeably the broadband absorption of adsorbed water. Spectrum of D2O in the pores differs from the spectrum of bulk water as for bandwidth so for band maximum. It was found that treatment of the pores by dry nitrogen leads to increasing hydrophilic properties of the material and to change water band contour. The D2О line widths in both the aerogels exceed those of free monomer in 1.1–3 times at the same pressure. Calculations of self-broadening coefficients of the D2O lines were performed using semi-empirical method based on the impact theory of broadening and includes the correction factors. The calculated results well agree with experimental data. Greater differences were found for the shift of the line centre. The D2O line shifts in the treated pores significantly exceed line shifts in the untreated pores. For some lines, these shifts have the opposite sign indicating complex nature of the molecule–wall interaction. 相似文献