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101.
The possibility to construct intercluster interaction potentials in continuous and discrete spectra is shown in one‐channel cluster model based on the classification of orbital states according to Young schemes. These potentials usually contain Pauli forbidden states, and correctly describe elastic scattering phase shifts taking into account resonance behavior and main characteristics of the bound states of nuclei in the considering cluster channel. The versions of intercluster interaction potentials describing the resonance nature of some phase shifts of the n7Li elastic scattering at low energies and the P2 ground state of 8Li in the n7Li cluster channel have been constructed for the demonstration of this approach. The possibility of describing the total cross sections of 7Li (n,γ)8Li within the energies from 5 meV (5 · 10‐3 eV) to 1 MeV, including resonance at 0.25 MeV, has been demonstrated for the potentials obtained in the potential cluster model with forbidden states. 相似文献
102.
Sangsu Park Seungjae Jung Manzar Siddik Minseok Jo Jubong Park Seonghyun Kim Wootae Lee Jungho Shin Daeseok Lee Godeuni Choi Jiyong Woo Euijun Cha Byoung Hun Lee Hyunsang Hwang 《固体物理学:研究快报》2012,6(11):454-456
We propose a selector‐less Pr0.7Ca0.3MnO3 (PCMO) based resistive‐switching RAM (RRAM) for high‐density cross‐point memory array applications. First, we investigate the inhomogeneous barrier with an effective barrier height (Φeff), i.e., self‐formed Schottky barrier. In addition, a scalable 4F2 selector‐less cross‐point 1 kb RRAM array has been successfully fabricated, demonstrating set, reset, and read operation for high cell efficiency and high‐density memory applications. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
103.
G. Pakhlova 《中国物理 C》2010,34(9):1195-1200
We review the recent experimental results on hadron spectroscopy from B-factories focusing on the exotic charmonium-like states.Among them we discuss the X(3872),Y(3940),Z(4430) +,Z(4050) +,Z(4250) + and Y(4140) states found in B-meson decays,the X(3940) and X(4160) states produced in double charmonium production,the Y(4260),Y(4325),Y(4660) and X(4630) states produced with initial-state radiation in e + eannihilation and the X(3915),Y(4350) states observed in two-photon collisions. 相似文献
104.
The K-shell X-ray fluorescence cross sections are determined experimentally for 10 elements such as Pb, Hg, Ir, W, Lu, Tm,
Dy, Tb, Gd and Nd at excitation energy of 661.6 keV associated with γ-rays of 137Cs radioisotope. The technique employed involves the measurement of total intensity of fluorescent K X-rays that follow the
photoeffect absorption of a known flux of γ-rays using a well type Nal(Tl) detector. The obtained results are compared with the available theoretical values and other
measured values. 相似文献
105.
106.
在样品池条件下,用脉冲激光670.8 nm线激发Li原子基态至2P态,测量了的反应碰撞能量转移截面。池温保持在888 K,Li原子密度为10~(13)cm~(-3)量级,而H_2气压控制在60~300 Pa之间,测量时间分辨荧光光谱,它由两部分组成,在脉冲激光激发的瞬间(不超过10 ns),荧光迅速增强至最大值;激发结束后,荧光强度按指数衰减,由衰减曲线得到2P态原子在不同H_2气压下的有效寿命。根据Stern-Volmer方程,有效寿命与H_2气压成线性关系,由该直线的斜率给出了总的猝灭截面(25.1±4.0)×10~(-16)cm~2,而从直线的截距得到辐射寿命为(270±54)ns。总的猝灭截面是反应与非反应碰撞截面之和,由在不同H_2气压下记录的瞬态(10 ns)荧光快速增强信号得到反应截面为(0.2±0.1)×10~(-16)cm~2,虽只占总猝灭截面的1/125,但它在Li(2P)+H_2的碰撞传能中所起的作用是不能略去的。 相似文献
107.
六种蜂花粉的红外光谱三级鉴别研究 总被引:3,自引:0,他引:3
采用傅里叶变换红外光谱(FTIR)结合二阶导数谱和热扰动下的二维相关红外光谱技术对6种不同花粉,即杏花花粉、油菜花粉、茶花花粉、西瓜花粉、荷花花粉和虞美人花粉,进行了快速无损的鉴别。结果表明,在一维红外光谱图上,不同花粉的蛋白质、脂肪和糖类物质的特征吸收峰在相对峰强和峰位上均存在一定的差异,在二阶导数谱上差异很明显。而在二维红外谱图上,由于6种花粉的自动峰及相关峰峰簇的位置和数量不同,其差别体现得更为明显和直观。因此,三级红外宏观指纹图谱法是鉴别不同蜂花粉种类的一种有效和快速检测方法。 相似文献
108.
109.
A method for extracting human gait series from accelerometer signals based on the ensemble empirical mode decomposition 下载免费PDF全文
In this paper,the ensemble empirical mode decomposition(EEMD) is applied to analyse accelerometer signals collected during normal human walking.First,the self-adaptive feature of EEMD is utilised to decompose the accelerometer signals,thus sifting out several intrinsic mode functions(IMFs) at disparate scales.Then,gait series can be extracted through peak detection from the eigen IMF that best represents gait rhythmicity.Compared with the method based on the empirical mode decomposition(EMD),the EEMD-based method has the following advantages:it remarkably improves the detection rate of peak values hidden in the original accelerometer signal,even when the signal is severely contaminated by the intermittent noises;this method effectively prevents the phenomenon of mode mixing found in the process of EMD.And a reasonable selection of parameters for the stop-filtering criteria can improve the calculation speed of the EEMD-based method.Meanwhile,the endpoint effect can be suppressed by using the auto regressive and moving average model to extend a short-time series in dual directions.The results suggest that EEMD is a powerful tool for extraction of gait rhythmicity and it also provides valuable clues for extracting eigen rhythm of other physiological signals. 相似文献
110.