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排序方式: 共有668条查询结果,搜索用时 0 毫秒
91.
D.V. Aleksandrov Yu.A. Glukhov A.S. Demyanova A.A. Ogloblln S.B. Sakuta V.V. Sukharevsky S.V. Tolokonnikov S.A. Fayans F.A. Gareev S.N. Ershov I.N. Borzov J. Bang 《Nuclear Physics A》1985,436(2):338-364
The reaction 14C(6Li, 6He)14N was investigated with 93 MeV 6Li ions in an angular interval of 7–26°. Angular distributions were analysed for the four most intense groups of 6He nuclei, corresponding to transitions to the ground (11+) and the excited (12+, 21?, 41?) states of 14N. In the theoretical analysis a mechanism of the spin-isospin excitation was suggested in the DWBA frame with the finite range of interaction and recoil in the light system (6Li6He) taken into account. In the calculations both shell-model wave functions and transition densities obtained in the theory of finite Fermi systems (FFS) were used. From the comparison between theory and experiment the Landau-Migdal force constant g′ is estimated in order to obtain some information on the degree of nuclear proximity to the threshold of pion condensation. 相似文献
92.
The convergence of a Neumann-series solution of the Marchenko equation in L
2[x, ∞) is proved and an explicit expression of the series solution is given. 相似文献
93.
The charge-exchange reaction (7Li, 7Be is described in the frame of a microscopical DWBA with central effective forces. The transition density for 7Li-7Be is calculated in two ways: with a one-particle model and with a cluster model, taking full account of recoil effects. The formalism is used for the cases of (7Li, 7Be reactions with 6Li and 40Ca. Further cross sections for reactions on 12C and 16O with and excitation energies around 4.5 and 6.2 MeV, respectively, are compared to new data obtained at the Kurchatov Institute. Here particle-hole states in an oscillator model were used to characterize the heavy system. Angular distributions are well reproduced, but absolute cross sections are 6–7 times too small. This indicates that the assumption of a direct one-step process is correct, but that tensor forces should be included as a component of the effective nucleon-nucleon force. 相似文献
94.
Cong Cheng Xiao‐Juan Han Zhen‐Qiang Dong Yan Liu Bang‐Jing Li Sheng Zhang 《Macromolecular rapid communications》2011,32(24):1965-1971
This paper describes the self‐assembly of rod–coil inclusion complexes, polyethylenimine–poly(ethylene glycol)–α‐cyclodextrin (PEI–PEG–α‐CD). It is demonstrated that α‐CDs should exclusively thread on the PEG block in PEI–PEG copolymers and the resulting complexes have both rigid block (PEG–α‐CD) and coil block (protonated PEI). By varying the rigid block fraction, aggregates with hollow spheres or rod‐like particles could be formed simply by self‐assembly in aqueous solution. 相似文献
95.
Hwang S Chi YS Lee BS Lee SG Choi IS Kwak J 《Chemical communications (Cambridge, England)》2006,(2):183-185
Asymmetric electrostatic interactions dependent on pH between the redox molecules and the terminal group on the top of the self-assembled monolayer (SAM) afford control of the electron transfer property of the SAM having the imidazole terminal group. 相似文献
96.
97.
Nguyen Thi Thu Huong Nguyen Chinh Cuong Ha Huy Bang Dao Thi Le Thuy 《International Journal of Theoretical Physics》2010,49(7):1457-1464
We study the pair production of scalar quark in a muon collider within the MSSM with CP violation. We show that including the CP phases can strongly affect the cross section of the process: \(\mu^{+}\mu^{-}\rightarrow \tilde{q}_{i}\bar{\tilde{q}}_{j}\). This could have an important impact on the search for squarks and the determination of the MSSM parameters at future colliders. 相似文献
98.
Wei Li Ning Hua Zhu Li Xian Wang Jian Hong Ke Shuo Fu Chen Bang Hong Zhang Liang Xie 《Optics Communications》2010,283(11):2324-5212
In this paper, the spectral relation between the master and the frequency-locked slave laser (FLSL) is investigated by the conventional technique of optical intensity modulation and optical heterodyne. Experimentally, we demonstrate that under complete and stable locking condition, the lightwave of the FLSL and the sidebands of the master laser produced by the optical intensity modulation are perfectly coherent (frequency coherence). Referring to our recent studies, the lightwave of the master laser and its corresponding sidebands are also perfectly coherent. Additionally, the spectral structures of two perfectly coherent lightwaves are identical in the level of wave train. Therefore, we indirectly verify that the spectral structures of the FLSL and the master laser are identical in the level of wave train. 相似文献
99.
100.
建立了地表水中伐昔洛韦、阿巴卡韦、恩替卡韦、齐多夫定、奈韦拉平、更昔洛韦、替比夫定、拉米夫定、阿昔洛韦和金刚烷胺10种抗病毒药物的超高效液相色谱-串联质谱联用检测方法。水样经ISOLUTE ENV+固相萃取柱富集净化后,以Waters ACQUITY UPLCTMBEH C18色谱柱(100 mm×2.1 mm i.d.,1.7μm)分离,0.1%甲酸-乙腈为流动相,在电喷雾离子源正离子模式下采用质谱多反应监测(MRM)进行测定。10种目标化合物的线性范围为0.5~200 ng/L,相关系数r20.993;方法的定量下限为0.2~5.0 ng/L,3个加标水平下的平均回收率为70.0%~104.0%,相对标准偏差(RSD)小于15%。该方法可用于地表水等相关水体中目标化合物的分析。 相似文献