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采用1H、13C NMR、同核相关谱(gCOSY)、异核相关谱(gHSQC)和远程偶合谱(gHMBC)等多种核磁方法研究了一种脒基碳酸氢盐化合物N, N′-双十二烷基乙脒基碳酸氢盐的结构和构型,证明了该化合物具有两种不同的构型:A[E, Z]和B[E, E],完成了该化合物两种构型中1H、13C NMR谱带的归属. 并考察了不同温度、不同极性溶剂(CDCl3和DMSO-d6)对此化合物两种不同构型比例变化的影响. 表明了N, N′-双十二烷基乙脒基碳酸氢盐在溶剂CDCl3中存在两种构型A和B, 随着温度的升高,构型B的比例增加. 在溶剂DMSO-d6中只存在一种构型A. 相似文献
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通过对4种含芳基噻唑半乳吡喃糖基胍的1H NMR谱的分析, 确证其糖苷键为β-构型, 对其一般特征进行了对比和讨论,并用1H-1H COSY, gHMQC, gHMBC, NOESY等2D NMR技术对它们的1H和13C NMR谱峰进行了全归属. 相似文献
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NMR核磁共振谱显示3,5-二甲基金刚胺盐酸盐是一个刚性结构,但其分子结构包含2个非对映体的立体构型形式. 我们通过利用DEPT,1H-1H COSY,HSQC和HMBC等技术所测得的二维谱图数据对NMR数据进行了完整的归属分析,其中13C NMR谱图显示在δ=29~54 ppm之间的十组峰表示所有碳的共振,而且由于不同的分子构象导致在13C NMR谱中有3个不同的季碳峰和1H NMR中的2个不同的甲基峰. 由于H-5的叔碳H原子与邻近CH2 的平面二面夹角均约为600,致使耦合常数极其小,波谱仪难以分辨它们从而使1H NMR峰为单重峰. 相似文献
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用1H 和13C NMR谱,FT-IR光谱等方法研究了聚氯乙烯(PVC)在限量空气氛室温下经60Coγ 射线辐照后的辐照效应.结果表明PVC 大分子链的脱HCl 方式,受辐射剂量的影响.当辐射剂量达到2.8×105Gy 时,PVC 以大分子链内脱HCl为主,产生部分-CH=CH-结构,使得-CHCl的运动受阻,表现为T2减小.不同溶剂对聚合物质子自旋-自旋弛豫时间(T2)的影响,反映出溶剂效应和聚合物链在溶剂中的“伸展”状态.而水质子峰随着辐照剂量的增大而逐渐向低场位移,则是由于HCl与溶剂中的H2O在微酸性溶液中发生了快速的质子交换之故. 相似文献
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XU Shuwei PAN Qiangyan ZHANG Tianmei YUAN Shuanggui ZHANG Xueqian SHI Shuanghui TIAN Jiaqi HUANG Wenda 《中国物理C(英文版)》1993,17(11):985-987
Activities of 183Os were produced by 39MeV α particles bombarding on a natural tungsten target.β+ spectrum with coincidence gate set on the strongest 382keV γ-rays of 183Os decay was measured.The endpoint energy of the β+ spectrum was determined and the QEC value of 183Os decay was extracted to be 2.24±0.10MeV which is in good agreement with the predicted value 2.30±0.10MeV on the basis of mass systematics. 相似文献
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Within the framework of a nonlinear chiral Lagrangian the mass spectra and the decay properties of 0^++ states below 2 GeV are studied. Assuming that f0(980), a0(980), K0(1430), and f0(1500) comprise an SU(3) nonet, we make a detailed prediction about the static properties of the 0^++ mesons. The substructure analysis of these states in terms of two- and four-quark components as well as a glueball component is carried out. We also consider the interaction Lagrangian and provide a preliminary study of the strong and radiative decays of the 0++ mesons. The scalar glueball masses and partial widths are also presented. In view of the fact that few data of 0++ mesons are clearly given in the present PDG (Particle Data Group) list and that the four-quark content of mesons is a hot issue both experimentally and theoretically, the predicted results of the paper may be helpful for upcoming experimental and theoretical studies of these mesons. 相似文献
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提出了计算苯甲醛亚胺、N-苯基亚胺、N-甲基亚胺、N-异丙基亚胺中亚胺基氮原子15N NMR化学位移的经验公式:δcal=δ0n+Δα+Δβ+Δγ+c. 按亚胺基氮原子和碳原子上两类取代基的不同分别结合最小二乘法通过线性回归各得到5种取代基参数,计算结果分别以其化学位移数据为样本点作回归检验,置信度为99.5%,最大误差Δδ≤3.1,大约有95%的15N NMR化学位移计算值的计算误差小于3.0(相对误差小于0.3%). 初步分析了芳香族亚胺苯环上对位取代基对亚胺基氮原子化学位移的影响. 相似文献
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SONG Li-Tao ZHOU Xiao-Hong ZHANG Yu-Hu GUO Ying-Xiang LEI Xiang-Guo ZHENG Yong LIU Min-Liang de Angelis 《中国物理C(英文版)》2005,29(8):736-740
High-spin states in 183Au have been studied experimentally using heavy-ion-induced fusion-evaporation reaction and standard in-beam γ-ray spectroscopic techniques. The level scheme of 183Au was revised and extended. A rotational band proposed as the unfavored signature branch of the πi13/2 band has been observed for the first time. Interaction properties between the two negative-signature bands of the πh9/2-πf7/2 system have been discussed for the light odd-A Au nuclei. 相似文献
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ZHANG Biao ZHU Li-Hua SUN Hui-Bin HE Chuang-Ye WU Xiao-Guang LU Jing-Bin MA Ying-Jun HAO Xin ZHENG Yun YU Bei-Bei LI Guang-Sheng YAO Shun-He WANG Lie-Lin XU Chuan WANG Jian-Guo GU Long 《中国物理C(英文版)》2011,35(11):1009-1012
High spin states in 107Ag are studied via the 100Mo(11B, 4n)107Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme has been updated and a new negative band belonging to 107Ag is identified. The new negative side band has been constructed and its configuration is tentatively assigned to πg9/2 νh11/2(g7/2/d5/2). 相似文献
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High-spin states in 169Re were studied and resulted in the identification of a strongly coupled band based on the 9/2-[514] Nilsson state and a decoupled band built on the h9/2 intruder proton orbital (nominally 1/2-[541]). The cranked shell nodel calculations present configuration-dependent deformations that can explain the different band crossing frecpiencies. The experimental 9/2-[514] band in Re shows the largest signature splitting at low spin among the known odd mass Re isotopes. After the alignment of a pair of the i13/2 neutrons, the phase of the splitting is inverted with a significantly reduced amplitude. Additionally, a three-quasipariticle band was observed and assigned to be built likely on the π9/2-[514]⊙AE configuration. 相似文献
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ZHU ShengJiang GAN CuiYun ZHU LingYan YANG LiMing XU RuiQing JON MyonGil JIANG Zhuo ZHANG Zheng 《中国物理C(英文版)》2000,24(11):1018-1023
Through study of the prompt r-rays emitted in the spontaneous fission of 252Cf, high spin states of neutron-rich odd-A 145,147Ce nuclei have been investigated. The levels in 147Ce have been extended. A collective band in 145Ce have been identified for the first time. The results from the particle rotor model calculations indicate that the yrast bands in 145Ce and 147Ce originate from vi13/2 orbital coupling and the ground states of 145Ce and 147Ce originate from (vh9/2,vf7/2) and vh9/2 configiration, respectively. No obvious octupole deformation was observed in these two isotopes, but a side band obtained in 147Ce may show some octupole correlations. 相似文献
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Study of in beam γ ray spectroscopy of 127I has been performed using 124Sn(7Li, 4n)127I reaction at 32 MeV beam energy. A new level scheme of 127I has been established including 25 new levels and 52 new γ transitions. Negative parity levels based on 11/2- π h11/2 particle state have been observed up to (35/2-) extending our knowledge of decoupled structures to the heavier iodine isotope. Two ΔI=2 yrast positive-parity levels have been proposed to be associated mainly with the πg7/2 configuration due to observations of several strong inter band transitions. Two weakly populated ΔI=2 positive parity levels and a high-lying ΔI=1 cascade have been newly identified and tentatively assigned as πd5/2 one-quasiparticle and three quasiparticle bands, respectively. 相似文献
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The ^8Li(p, d)^7 Li reaction plays an important role in the inhomogeneous Big Bang nucleosynthesis and in the seed-nuclide production phase for the r-process. For the first time, its angular distribution at backward angles was measured in inverse kinematics at Ec.m.=4.0 MeV by using an ^8Li secondary beam. The result of measurement includes the contributions of ^8Li(p, d0)^7Li and ^8Li(p, d1)^7Li^*. The ^8Li(p, d0)^7Li component is estimated to be 40%-58% in the mixture angular distribution by analysing the measured result. 相似文献
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Mixing between the 23S1 and 13D1 Ds is studied within the 3P0 model. If mixing between these two 1- states exists, Ds1*(2700)± and DsJ*(2860)± could be interpreted as the two orthogonal mixed states with mixing angle θ≈ -80° in the case of a special β for each meson. However, in the case of a universal β for all mesons, Ds1*(2700)± could be interpreted as the mixed state of 23S1 and 13D1 with mixing angle 12° < θ < 21° but DsJ*(2860)± seems difficult to interpret as the orthogonal partner of Ds1*(2700)±. 相似文献