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121.
Fenglei Gao 《Applied Surface Science》2010,256(11):3357-9406
Chemical vapor deposition (CVD) growth of horizontally aligned single-walled carbon nanotubes (SWNTs) was studied using two representative carbon source sources: ethanol and methane. The resulting SWNTs were compared for similar reaction conditions which were based on the formation of Ni metal nanoparticles selective electrochemical deposition (SED) on the defect sites of SWNTs. The products were analyzed by Raman spectroscopy and SEM. The results demonstrate that methane was much better carbon source for growing high quality horizontal alignment of SWNTs than ethanol due to the etching effects of OH radicals on the SWNTs. 相似文献
122.
贴片电阻表面缺陷自动识别方法 总被引:1,自引:0,他引:1
贴片电阻生产过程中的缺陷主要依靠人工在显微镜下检测,速度慢、长期成本高、误检率高.针对贴片电阻单元具有排列整齐、结构简单、图像灰度级少的特点,在贴片电阻图像二值化、边缘提取、直线检测基础上,以相邻电阻单元的相关系数作为电阻缺陷判别依据,提出基于子图投影匹配的快速缺陷检测方法.采用主分量分析法压缩图像数据量,提取缺陷特征,以基于支持向量机对贴片电阻缺陷进行分类并建立实验系统.缺陷检测及识别实验表明,缺陷检测正确率为92.5oo,算法的快速性和识别准确度满足系统快速高精的要求. 相似文献
123.
We propose a scheme for the non-destructive detection of an unknown Werner state by detecting the steady-state output intensity of the probe field. Moreover, with a similar mechanism, a Werner state can be generated as a stationary state by pumping the cavity field. The numerical simulations indicate that both the state detection and generation schemes are effective and efficient. 相似文献
124.
G. Sidenius 《辐射效应与固体损伤》2013,168(1-4):145-155
An analysis of some of the fundamental and special physical processes occurring in discharge and plasma ion sources is presented. The main purpose of the lecture is to present to the users of ion sources some key elements of information, of which not all may be generally recognised and which hopefully will be of value for a better understanding of the operational problems related to the complex behaviour of discharge and plasma ion sources. 相似文献
125.
Information concerning the effect of irradiation on the optical properties of materials in the infrared, sub-mm-and mm-wavelength regions is of increasing importance in fusion plasma diagnostics. The radiation induced transmission loss of a number of materials has therefore been investigated at wavelengths in the ranges 200 nm to 40 μm and 0.23 to 2.0 mm. The samples were irradiated with doses of up to 1010 rad in a nuclear reactor. While germanium shows considerable transmission loss at doses as low as 106 rad, and the transmission of TPX decreases at 109 rad, other materials, e.g. fused quartz and possibly ZnSe, exhibit sufficient radiation hardness for use in fusion plasma diagnostics. 相似文献
126.
The spin Hamiltonian parameters (g factors g //, g ⊥ and hyperfine structure constants A //, A ⊥) of Cu2+ in K2SO4?Na2SO4?ZnSO4 glasses are calculated from the high-order perturbation formulas of 3d9 ion in tetragonal octahedral sites. The calculated results are in agreement with the observed values. Since the EPR parameters are sensitive to the local structure of a paramagnetic impurity center, the defect structure of Cu2+ center in K2SO4?Na2SO4?ZnSO4 glasses is estimated. The validity of results is discussed. 相似文献
127.
《代数通讯》2013,41(5):2229-2270
ABSTRACT Using some ideas of Brauer, we introduce what we call generalized Brauer algebras and, as a special case, Brauer orders. We show that many well-known classes of so-called crossed product algebras, and in particular, the well-known crossed product orders, can be obtained as special instances of our construction. We prove several results showing when Brauer orders are Azumaya, maximal, hereditary or Gorenstein. 相似文献
128.
Effect of defect configuration on the localization of phonons in two-dimensional phononic crystals 总被引:1,自引:0,他引:1
Effects of defect location on the defect frequency and the localization of phonons are investigated in two novel kinds of model, created by moving the location of the native cylinder and inserting an ad-cylinder in the central cellular respectively. The results show that the defect frequency in Model 1 is only related to the distance, while in Model 2, is related not only to the distance, but also to the moving direction. From the pressure distribution, obvious localization phenomenon is found. The position and shape of the localized energy are varied with the position of the defect. 相似文献
129.
《偏微分方程通讯》2013,38(5-6):877-906
ABSTRACT We discuss the convergence issue for the generalized Ginzburg-Landau functional which penalizes the Lp -energy. We prove the strong convergence for non-integer p and obtain the obstruction for strong convergence for integer p. In the presence of obstruction, we show the limiting couple varifold is a (generalized) stationary (n ? p)-varifold. 相似文献
130.
Qian Yang Bing-Yu Zhang Wei-Dong Ye Jian-Yong Yuan Duan-Jun Xu Jing-Jing Nie 《Journal of chemical crystallography》2008,38(9):659-661
Abstract The title compound (common name eplerenone), C24H30O6, is an aldosterone receptor antagonist. From the isopropyl acetate solution the compound crystallizes in monoclinic space
group P 21 with a = 8.811(1) ?, b = 11.250(1) ?, c = 11.079(1) ?, β = 93.822(12)°, Z = 2. The molecule contains three six membered rings, two five membered rings and one three membered ring. Both five membered
rings display envelope conformation, whereas three six membered rings show different conformation: chair, half-chair and envelope.
In the crystal the eplerenone molecules link to one another via intermolecular weak C–H···O hydrogen bonding to form the smaller
cavity of 12.0(1) ?3 between eplerenone molecules, no solvent molecule filled in this cavity.
Index Abstract In the title molecule three six-membered rings show different conformation. Weak C–H···O hydrogen bonding links adjacent molecules
to form the small cavity 12.0(1) ?3, no solvent molecule filled in the cavity.
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