取代四氢β－咔啉的￣（1）HNMR和立体化学研究

报道了１，２－二取代、１，３－二取代以及１，２，３－三取代四氢β－咔啉类化合物的￣（１）ＨＮＭＲ数据，讨论了１位质子的化学位移值的大小与１位碳构型的关系，并根据ＮＯＥ效应，分析了化合物在核磁共振测定条件下的构象。     

ESR研究非晶Ag￣＋导体的晶化

用电子自旋共振（ＥＳＲ）方法对非晶Ａｇ￣＋离子导体０．８５ＡｇＩ～０．１５Ａｇ＿４Ｐ＿２Ｏ＿７的热处理晶化过程进行研究，在样品中掺入微量（约１×１０￣（－３）ｇ／ｇ）的Ｍｎ￣（２＋）或Ｖ￣（４＋）离子作为自旋探针离子，它们的ＥＳＲ谱强度随升温线性减弱，当样品完全晶化时ＥＳＲ谱消失。这样测定的样品完全晶化的温度分别为９８℃（掺Ｍｎ的）和１０８℃（掺Ｖ的）．本文还对Ｍｎ￣（２＋）和Ｖ￣（４＋）的ＥＳＲ谱进行了分析。     

3－甲酰腙一利福霉素SV及其异构体的研究

用发酵和化学法合成的两个３－甲酰腙—利福霉素ＳＶ样品（１￣＃，２￣＃）具有不同的物理化学性质，本文用多种ＮＭＲ技术，如￣１Ｈ，￣＿（１３）Ｃ，ＤＥＰＴ，￣１ＨＨＣＯＳＹ，反相摸式的￣１Ｈ－￣（１３）ＣＣＯＳＹ及远程￣１Ｈ－￣（１３）ＣＣＯＳＹ，并结合红外及紫外一可见光谱测试结果进行综合分析，确定样１￣＃及样２￣＃分别为酰胺式主产品及亚胺醇式导构体。根据实验结果对样１￣＃的异构化反应进行了初步的探讨．     

DMF－H＿2O和DMF－D＿2O体系中￣（14）N弛豫的动态同位素效应的研究

本文测定了ＤＭＦ－Ｈ＿２Ｏ和ＤＭＦ－Ｄ＿２Ｏ体系在全部浓度范围内（摩尔分数为０～１）ＤＭＦ分子中四极核￣（１４）Ｎ的弛豫时间，讨论了弛豫的溶剂同位素效应和影响四极核弛豫的因素。研究结果表明，体系中￣（１４）Ｎ的弛豫与溶剂水分子的动力学行为有着密切的联系，在无限稀释条件下溶质分子的运动完全受溶剂分子的控制．     

用￣1H NMR法研究［Co（Xacac）＿2（Me－en）］ClO＿4的重氢化

应用￣１ＨＮＭＲ技术推定了新合成的二（３－取代Ｘ基－２，４－戊二酮）．Ｎ－甲基乙二胺合钴（Ⅲ）配合物：［Ｃｏ（Ｘａｃａｃ）＿２（Ｍｅ－ｅｎ）］ＣｌＯ＿４（Ｘ＝ＣＨ＿３、Ｃｌ、ＮＯ＿２）的Δ（Ｒ）∧（Ｓ）和Δ（Ｓ）∧（Ｒ）异构体的空间构型，测定了各配合物异构体手性配位氮原子上的重氢化速率常数ｋ＿Ｄ值（３４．０℃）．结果表明，取代基Ｘ对ｋ＿Ｄ值有着显著影响。     

多相氧载体CoO－MgO和氧分子作用的ESR研究

用ＥＳＫ研究多相氧载体ＣｏＯ－ＭｇＯ表面上氧的吸附作用，发现在７７－１５０Ｋ温度范围内表面Ｃｏ￣（２＋）离子和Ｏ＿２的结合是可逆的，吸附产生Ｃｏ￣（３＋）－自由基加合物有超精细结构的ＥＳＲ谱；当温度增加，吸附态自由基发生转移并稳定在Ｍｇ￣（２＋）离子上形成Ｍｇ￣（２＋）－Ｏ自由基，文中着重讨论Ｃｏ￣（３＋）－自由基的电子结构和成键本质，认为自由基是通过自旋成对的方式形成的，由于σ－л键作用引起的自旋极化以及由于电子离域作用而引起的偶极作用与ＥＳＲ制的超精细结构线产生有关。     

焙烧温度对Mg(Al)O复合物结构和表面酸碱性质影响的研究

分别在６７３。８７３和１０７３Ｋ分解Ｍｇ／Ａｌ摩尔经继３的水滑石生成Ｍｇ（Ａｌ）Ｏ复合物，ＸＲＤ测定均ＭｇＯ物相，８７３Ｋ以上焙烧的样品同时存在ＭｇＡｌ２Ｏ４尖晶石物相，微量吸附量热测定其表面酸碱中心的强度和密度，发现碱中心强度和密度顺序为ＭＡＯ－２〈ＭＡＯ－３≈ＭＡＯ－１，而酸中心强度和密度顺序是：ＭＡＯ－１〉ＭＡＯ－３≈ＭＡＯ－２，红外光谱表明，Ｍｇ（Ａｌ）Ｏ复合物表面酸碱中心主要存在Ｌ酸，碱     

邻巯基氧化吡啶双齿配位的钴化合物的￣（1）HNMR研究

对四种单核钴化合物Ｃｏ（ｍｐｏ）＿３·ＣＨ＿３ＣＮ（Ⅰ），ＣＯ（ｍｐｏ）＿２ＰＢｕ＿３（Ｄ），Ｃｏ（ｍｐｏ）＿２Ｐｙ（Ⅲ）和Ｃｏ（ｍｐｏ）＿２Ｐｙ＿２（Ⅳ）的￣１ＨＮＭＲ作了研究，讨论了它们的分子结构与磁性及电子结构之间的关系，确认化合物（Ⅱ）在ＤＭＳＯ溶液中被解离为Ｃｏ（ｍｐｏ）＿２和ＰＢｕ＿３，而其它三种化合物仍保留着固态结构。     

Nd1—xBaxMnO3和La0.67Mg0.33Mn0.85M0.15O3（M=Mn,Ga,Fe）中Mn？…

研究了Ｎｄ１－ｘＢａｘＭｎＯ３和Ｌａ０．６７Ｍｇ０．３３Ｍｎ０．８５Ｍ０．１５Ｏ３的导电性，发现Ｍｎ位的自旋磁矩排列状态一大小 和对体系的导电性有强烈的影响，在Ｎｄ１－ｘＢａｘＭｎＯ３中，当Ｍｎ＾３＋／Ｍｎ＾４－的浓度比值为２：１．１：１，１：２时，电阻率出现半导体－金属转变，推论该类体系的导电性首先由体系中Ｍｎ＾３＋和Ｍｎ＾４＋自旋磁矩形的磁结构状态决定，然后才取决于由Ｂａ掇杂浓度所决定的载流子     

聚醚酰亚胺（YS－30）链结构的1D和2DNMR谱分析

聚醚酰亚胺（ＹＳ－３０）是一种可溶性的聚酰亚胺，本文对它的￣（１３）ＣＮＭＲ谱，￣１ＮＮＭＲ谱和ＣＯＳＹ谱进行了研究．经过分析，对￣（１３）ＣＮＭＲ和￣１ＨＮＭＲ谱作出了归属，确认了聚醚酰亚胺的链结构．     

High-lying excited states in ~(10)Be from the ~9Be(~9Be,~(10)Be)~8Be reaction

A transfer-reaction experiment of ~9Be(~9Be,~(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ~(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the observed high-lying resonant states,reconstructed from theα+~6He and t+~7Li decay channels,agree with the previously reported results.In addition,two new resonances at 15.6 and 18.8 Me V are identified from the present measurement.The 18.55 Me V state is found to decay into both the t + ~7Lig:s: and t + ~7Li?(0.478 MeV) channels, with a relative branching ratio of 0:93 ± 0:33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei.     

An Investigation of ~4He+~(12)C and ~4He+~(16)O Reactions Using the Cluster Model

The α-target semimicroscopic single folding potentials have been derived by folding a composite (repul-sive and attractive) effective α-α interaction with the α-cluster distribution density in the target nuclei. The obtained potentials are considered as the real part of the nuclear optical model potentials, while the imaginary parts are phe-nomenologicaly expressed using the Woods-Saxon form. Nine sets of measured experimental data of the 4He+12C and 4 He+16O elastic rainbow scattering over the energy range 80-240 MeV are analyzed using the obtained potentials. The data are successfully reproduced using the extracted potentials. The resulted reaction cross sections are also investigated and compared with the available corresponding data.     

Measurement of the ~2H(~7Be,~6Li)~3He reaction rate and its contribution to the primordial lithium abundance

In the standard Big Bang nucleosynthesis(SBBN) model, the lithium puzzle has attracted intense interest over the past few decades, but still has not been solved. Conventionally, the approach is to include more reactions flowing into or out of lithium, and study the potential effects of those reactions which were not previously considered.~7Be(d,~3He)~6Li is a reaction that not only produces~6Li but also destroys~7Be, which decays to~7Li, thereby affecting~7Li indirectly. Therefore, this reaction could alleviate the lithium discrepancy if its reaction rate is sufficiently high.However, there is not much information available about the~7Be(d,~3He)~6Li reaction rate. In this work, the angular distributions of the~7Be(d,~3He)~6Li reaction are measured at the center of mass energies Ecm = 4.0 Me V and 6.~7Me V with secondary~7Be beams for the first time. The excitation function of the~7Be(d,~3He)~6Li reaction is first calculated with the computer code TALYS and then normalized to the experimental data, then its reaction rate is deduced. A SBBN network calculation is performed to investigate its influence on the~6Li and~7Li abundances. The results show that the~7Be(d,~3He)~6Li reaction has a minimal effect on~6Li and~7Li because of its small reaction rate. Therefore,the~7Be(d,~3He)~6Li reaction is ruled out by this experiment as a means of alleviating the lithium discrepancy.     

Bremsstrahlung neutrino energy loss for ~(24)Mg,~(28)Si,~(32)S,~(40)Ca,~(56)Fe in strong electron screening

Based on Weinberg-Salam theory the bremsstrahlung neutrino energy loss for nuclei 24Mg,28Si,32S,40Ca and 56Fe are investigated in strong electron screening.Our results are compared with those of Dicus' and show that the latter are higher by 2 orders of magnitude in the density-temperature region of 108 g/cm3 ρ/μe 1011 g/cm3 and 2.5 T9 4.5.On the other hand,the factor C shows that the maximum differences are 99.16%,99.13%,99.12%,99.055%,99.040% corresponding to the nuclei 24Mg,28Si,32S,40Ca and 56Fe.     

Langevin study of neutron emission in the reactions ^16O＋^181Ta and ^19F＋^178Hf^＊

The pre-scission neutrons measured in the reactions 16O 181Ta and 19F 178Hf are studied via a Langevin equation coupled with a statistical decay model. We find that because of the mass asymmetry of different entrance channels, the spin distributions of compound nuclei would be different, consequently, the measured neutrons in these two reactions would also different. This means that the entrance channel will affect the particle emission in the fission process of hot nuclei.     

Bremsstrahlung neutrino energy loss for ~(24)Mg, ~(28)Si, ~(32)S, ~(40)Ca, ~(56)Fe in strong electron screening

Based on WeinbergoSalam theory the bremsstrahlung neutrino energy loss for nuclei ~(24)Mg, ~(28)Si, ~(32)S, ~(40)Ca and ~(56)Fe are investigated in strong electron screening. Our results are compared with those of Dicus' and show that the latter are higher by 2 orders of magnitude in the density-temperature region of 10~8 g/cm~3 ≤ρ/μ_e≤10~(11) g/cm~3 and 2.5 ≤ T_9 ≤4.5. On the other hand, the factor C shows that the maximum differences are 99.16%, 99.13%, 99.12%, 99.055%, 99.040% corresponding to the nuclei ~(24)Mg, ~(28)Si, ~(32)S, ~(40)Ca and ~(56)Fe.     

Simulation of the fission dynamics of the excited compound nuclei ~(206)Po and ~(168)Yb produced in the reactions ~(12)C+~(194)Pt and ~(18)O+~(150)Sm

A two-dimensional dynamical model based on the Langevin equation was used to study the fission dynamics of the compound nuclei ~(206)Po and ~(168)Yb produced in the reactions ~(12)C+~(194)Pt and ~(18)O+~(150)Sm,respectively.The fission cross section and average pre-scission neutron multiplicity were calculated for the compound nuclei ~(206)Po and ~(168)Yb,and results of the calculations compared with the experimental data.The elongation coordinate was used as the first dimension and the projection of the total spin of the compound nucleus onto the symmetry axis,K,considered as the second dimension in the Langevin dynamical calculations.In the two-dimensional calculations,a constant dissipation coefficient of K and a non-constant dissipation coefficient have been used to reproduce the abovementioned experimental data.It is shown that the two-dimensional Langevin equation can satisfactorily reproduce the fission cross section and average pre-scission neutron multiplicity for the compound nuclei ~(206)Po and ~(168)Yb by using constant values of the dissipation coefficient of K equal to γκ=0.18(MeV zs)~(-1/2) and γκ= 0.20(MeV zs)~(-1/2)for the compound nuclei ~(206)Po and ~(168)Yb,respectively.     

Study of ~3He inelastic scattering on ~(13)C and ~(14)C at 37.9 MeV

The differential cross sections of elastic and inelastic scattering of ³He ions on ¹³C and ¹⁴C have been studied at an energy of 37.9 MeV with a double folding model based on M3Y-Reid effective nucleon-nucleon interaction. The resulted parameters have been used for the standard Distorted Wave Born Approximation calculations of angular distributions corresponding to different excitations levels of ¹³C and ¹⁴C and deformation parameters have been deduced.     

Strong Decays of Charm Mesons D_1~*(2680), D_3~*(2760), D_2~*(3000)

In this article, we assign the higher charm mesons D1_*(2680), D3_*(2760) and D2_*(3000) to be the 2S 1~-, 1D3~- and 1F 2~+ states, respectively, and study the two-body strong decays to the ground state charm mesons and light pseudoscalar mesons with the heavy meson effective theory. We obtain the ratios among the strong decays, which can be confronted to the experimental data in the future and shed light on the nature of those higher charm mesons.     

Reanalysis of Elastic Scattering of ~6Li + ~(209)Bi Reaction Using a New DensityDistribution of ~6Li Nucleus

In the present paper, the elastic scattering of6 Li + 209 Bi system is reanalyzed by using the double folding model (DFM) at energies near the Coulomb barrier (ELab=29.9 and 32.8 MeV). With this goal, a new density distribution of6 Li nucleus, the no-core full configuration (NCFC) density distribution (DD), is used to obtain the real potentials in DFM calculations. The NCFC DD results are compared with the results of both gaussian shape (GS) DD and an earlier study as well as the experimental data. This comparison provides information about the similarities and differences of the models used in calculations.