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14N核四极共振自旋系统的自旋-晶格弛豫是一种双指数弛豫。本文介绍了14N核四极共振自旋系统的自旋-晶格弛豫时间的3种测量方法,利用可变多面体方法对实验数据进行拟合,获得了14N核四极共振自旋系统的自旋-晶格弛豫时间T1s和T11,对有关文献中关于核四极共振弛豫时间的测量的3个观点提出了质疑。 相似文献
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 ̄14N核四极共振自旋系统的自旋-晶格弛豫是一种双指数弛豫。本文介绍了 ̄14N核四极共振自旋系统的自旋-晶格弛豫时间的3种测量方法,利用可变多面体方法对实验数据进行拟合,获得了 ̄14N核四极共振自旋系统的自旋-晶格弛豫时间T_1s和T_11,对有关文献中关于核四极共振弛豫时间的测量的3个观点提出了质疑。 相似文献
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氮-14远程核四极共振谱仪 总被引:1,自引:0,他引:1
为了满足检测与探头有一定距离的含氮化合物的核四极共振信号,本文研制了一台结构简单,造价低廉的核四极共振操测仪.它利用了脉冲付里叶变换技术,可将获得的核自由感应衰减信号或者回波信号进行相干累加.整个系统分硬件和软件两大部分.前者由射频脉冲放大器(约500W脉冲输出功率),探头,接收机,MCS-96型单片机和PC机构成.后者由单片机上的脉冲序列程序与PC机上的数值信号处理程序组成.利用这台谱仪,可以在几十秒时间内得到距离探头线圈10cm内的典型 ̄(14)N样品的核四极共振谱. 相似文献
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氮-14远程核四极共振谱仪 总被引:1,自引:1,他引:0
为了满足检测与探头有一定距离的含氮化合物的核四极共振信号,本文研制了一台结构简单,造价低廉的核四极共振操测仪.它利用了脉冲付里叶变换技术,可将获得的核自由感应衰减信号或者回波信号进行相干累加.整个系统分硬件和软件两大部分.前者由射频脉冲放大器(约500W脉冲输出功率),探头,接收机,MCS-96型单片机和PC机构成.后者由单片机上的脉冲序列程序与PC机上的数值信号处理程序组成.利用这台谱仪,可以在几十秒时间内得到距离探头线圈10cm内的典型14 N样品的核四极共振谱. 相似文献
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用密度矩阵理论和计算机模拟较详细地讨论了自旋I=3/2核四极共振(NQR)粉末体系对梳状脉冲的响应以及偏共振效应的影响.在偏共振强度(包括谱线的非均匀增宽)较小的条件下.由它获得的谱与二维章动谱是相似的.但是实验所需时间能够减少近两个数量级.
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用15N+ 1H→12C+4He+4.43MeV(γ射线)的共振核反应测量超导体Pd H中氢的浓度与深度之间关系,是较精确的方法。因为 1)深度分辨率高;2)γ射线能透过低温和真空系统而易于探测;3)反应共振能量为6.385MeV,为孤立共振,共振宽度很窄(6keV),易于分开;4)有大的反应截面(0.45b),灵敏度高。本文讨论了这种方法的原理、实验装置和不同制备条件下Pd(H)超导体中氢分布、并与压力荷电样品的结果相比较,对氢在这类超导体中的行为提出一些新的不同的看法。
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The 13C(3He, d) reaction at a beam energy of 43.6 MeV was used to examine levels of 14N up to 11.7 MeV over an angular region including the main stripping peaks. Many spectroscopic factors were determined reliably for known states and found to be mostly in good agreement with calculations for the stronger levels. Several new spin or parity assignments are made at high excitation. 相似文献
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Absolute differential cross sections for the 13C(d, n)14N reaction were measured at deuteron bombarding energies of 4.5, 5.0 and 5.5 MeV. Spectroscopic factors and statistical compound-nucleus contributions are obtained by treating the observed cross sections as an incoherent sum of distorted-wave Born approximation and compound-nucleus contributions. Energy-averaged spectroscopic factors are derived. An anomaly is observed in the yield for the 2.313 MeV T= 1 state. 相似文献
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A.F. Zeller G.T. Hickey D.C. Weisser D.F. Hebbard B.A. Robson 《Nuclear Physics A》1978,301(1):130-140
Reactions induced by 14N on 26Mg at bombarding energies of 60–95 MeV have been studied. Angular distributions for states populated in 29Si by the (14N, 11B) reaction and in 30Si by the (14N, 10B) reaction have been compared with Hauser-Feshbach and DWBA calculations to determine the reaction mechanism and to deduce spectroscopic information. The cross sections for the states populated in 29Si and 30Si are in poor agreement with statistical model calculations, indicating a non-compound nucleus mechanism. 相似文献
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G. Proudfoot H.S. Bradlow P.S. Fisher N.S. Godwin J. King D. Sinclair W.D.M. Rae 《Nuclear Physics A》1980,345(1):278-301
11B and 13C induced two-nucleon transfer data on 14N, 15N and 16O are compared with exact finite-range sequential transfer calculations. The data appear to be consistent with this reaction model and the assumed shell-model structure of the states populated. Single-nucleon transfer data on these targets is also analyzed using the DWBA. Modifications to the exit channel optical potential are required to obtain agreement with shell-model spectroscopic factors. 相似文献
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A. Cunsolo A. Foti G. Immè G. Pappalardo G. Raciti N. Saunier B.T. Kim 《Nuclear Physics A》1981,355(1):261-268
Angular distributions of the charge exchange reaction 14C(6Li, 6He)14N leading to the 1+ ground state and 3.95 MeV 1+, and 5.20 MeV 2? excited states at the 34 MeV incident beam energy were analyzed and measured. The 62 MeV data of Goodman et al. were also reanalyzed. The direct one-step charge exchange caused by the spin-isospin dependent term in the two-body interaction can account well for the observed data. The strength of spin-isospin dependent effective interaction (gaussian form with a range parameter of 1.8 fm) was extracted to be 18.5 MeV. 相似文献
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We present Time-Dependent Hartree-Fock calculations for the massasymmetric system 14N + 12C in the range 20 ? Ecm ? 114. A simplified effective interaction of the Skyrme form has been used and the orbital angular motion of the ions has been treated in the rotating frame approximation. The overall magnitude of the calculated fusion cross-section is in agreement with experiment. The calculated differential cross section for direct inelastic reaction products is proportional to . This is in contrast to the exponential decrease observed experimentally. 相似文献
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Angular distributions of cross section and vector analyzing power have been measured for the 14N(d, p)15N reaction at Ed = 10 MeV for transitions to levels up to 8.6 MeV excitation in 15N. Distorted wave Born approximation calculations and calibration curves were used to determine total and orbital angular momenta and spectroscopic factors of the transferred neutrons. The results were compared with different theoretical approaches. 相似文献