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61.
Oriňák Andrej Arlinghaus Heinrich Frank Vering Guido Justinová Martina Oriňáková Renáta Turčániová L’udmila Halama Maroš 《平面色谱法杂志一现代薄层色谱法》2003,16(1):23-27
JPC – Journal of Planar Chromatography – Modern TLC - Two interfaces have been tested for coupling thin-layer chromatography (TLC) with time-of-flight secondary-ion mass spectrometry... 相似文献
62.
The terminology ‘ID frequency’(w ID) is proposed after analyzing the 1D active photonic crystal based on the transfer matrix method. The relationship between wID and the structure parameters of the photonic crystal is investigated. 相似文献
63.
Elastic electron scattering on the exotic light nucleus28S is investigated in the plane wave Born approximation. The variation of the squared form factors of28S with momentum transfer is compared with that of32S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive
to the alteration of the charge density distribution of halo protons in28S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei. 相似文献
64.
65.
聚合物分散液晶光栅的衍射特性的研究 总被引:9,自引:4,他引:5
报道了一种由聚合物分散液晶膜与具有周期性条状电极结构板结合的新型光栅器件,借助于聚合物分散液晶膜的电光特性,这种栅对入射光的散射或衍射取决于对其施加的电压,即它是电场可调的,实验结果显示出当驱动电压超过器件器件阈值电压时,衍射光的强度和衍射斑的可见级次被电场调制,而且它能入射光的线性偏振态变为椭圆偏振态。 相似文献
66.
注入控制铜蒸气激光方向性时间过程测量 总被引:1,自引:0,他引:1
实验研究了注入控制对铜蒸气激光非稳腔输出光束质量的影响,从输出光发散角时间分辨过程的测量结果说明注入加速被注入腔内激光发散角的减小过程。由于被注入腔内放大自发辐射的存在,为得到较好的注入控制效果,注入光的脉宽和进入被注入腔的延时必须恰当。 相似文献
67.
C.J. Lu H.M. Shen S.B. Ren Y.N. Wang 《Applied Physics A: Materials Science & Processing》1997,65(4-5):395-401
3 thin films is systematically studied by using X-ray diffraction (XRD). The PbTiO3 thin films with different average grain sizes were prepared on various substrates by a sol-gel process. The films on NaCl
and fused glass are randomly grain-oriented, while those on (111)Pt/Ti/SiO2/Si are highly {100} cubic index grain-oriented . It is found from the XRD patterns of the films on NaCl that with decreasing
average grain size from 230 to 80 nm, the intensities of high h index (h>l) peaks (hkl), such as (100), (110), (200), (201),
(210), (211), etc., decrease rapidly and ultimately disappear, whereas another set of peaks (lkh), including (001), (002),
(102), (112), etc., are still intense. This interesting result suggests that at grain size below a certain critical size an
increasing number of grains no longer show 90°-domains, which is confirmed by TEM observations. Meanwhile, X-ray evidence
of such a grain-size-related absence of 90°-domains is also found for PbTiO3 films on Pt(111) and fused-glass substrates. The volume fractions of single-domain grains (without 90°-domains) in the films
are estimated from their XRD patterns. By combining SEM and TEM investigations, the critical grain size for the formation
of 90°-domains is further determined to be near 200 nm.
Received: 19 December 1996/Accepted: 24 March 1997 相似文献
68.
Berry Frank J. Ren Xiaolin Gancedo J. Ramón Marco José F. 《Hyperfine Interactions》2004,156(1-4):335-340
Hyperfine Interactions - Perovskite-related phases of the type LaFe1?x Co x O3 (x=0 and 0.5) have been synthesised by milling techniques. The materials are of smaller particle size and more... 相似文献
69.
AN EFFECTIVE APPROACH FOR TWO-DIMENSIONAL POLARONS IN AN ASYMMETRIC QUANTUM DOT 总被引:1,自引:0,他引:1 下载免费PDF全文
Within the framework of Feynman-Haken path integral theory, we calculate the ground-state energy of two-dimensional polarons in asymmetric quantum dots for arbitrary electron-phonon coupling constants. From a general three-dimensional Hamiltonian, some interesting problems, such as polarons in quasi-one-dimensional quantum wires and quasi-zero-dimensional asymmetric or symmetric quantum dots can be easily discussed only by taking different limit in the whole coupling regime. After the numerical calculation, we find that the relative polaronic correction increases monotonically with the decrease of effective dot size, and it becomes more pronounced with increasing dimension and asymmetry. Moreover, despite the insensitivity of relative polaronic enhancement to the variation of coupling constant at weak coupling, the correction is related to the coupling constant as the latter becomes larger. 相似文献
70.
Stopband phenomena are reported in the passband of left-handed metamaterials. The samples with linear defect are designed by removing one layer of split ring resonators (SRRs). It is shown that the left-handed transmission peaks have a distinct transform with the relative deviation of the SRRs centre from the wire centre 8, from a single left-handed peak, double left-handed peaks with different magnitude to no transmission peak, i.e. left-handed properties of metamaterials disappear. Numerical simulation shows that the change of 8 makes the effective permeability shift at a frequency range, where stopband occurs. It is thought that the stopband in left-handed passband is due to the symmetry breaking between SRRs and wires in the metamaterials. 相似文献