beta-delayed proton decays of Tb-140 and Dy-140 as well as the spin and parity of Dy-143

Tb-140 and Dy-141 were produced via fusion evaporation in the reaction Ca-40+Cd-106. Their beta-delayed proton decays were studied by means of "p-gamma" coincidence in combination with a He-jet tape transport system, including half-lives, proton energy spectra, gamma-transitions following the proton emissions, and the branching ratios to the low-lying states in the grand-daughter nuclei. The ground-state spins and parities of Tb-140 and Dy-141 were extracted as 7(+/-) and 9/2(+/-), respectively, by fitting the experimental data with a statistical model calculation. The configuration-constrained nuclear potential energy surfaces (NPES) of Tb-140 and Dy-141 were calculated by using the Woods-Saxon Strutinsky method, which indicate the ground-state spins and parities of Tb-140 and Dy-147 to be 7(+) and 9/2(-), respectively. In addition, the configuration-constrained NPES of Dy-143 was also calculated by using the same method. From the NPES a 1/2(+) ground state and a 11/2(-) isomer with the excitation energy of 198keV were found. The calculated results are consistent with our experimental data on the decay of Dy-143 reported in Eur. Phys. J., 2003, A16: 347-351.

beta-delayed proton decays and spin assignments for Tb-140, Dy-141 and Dy-143

The proton-rich isotopes Tb-140 and Dy-141 were produced via the fusion evaporation reaction Ca-40+ Cd-106. Their beta-delayed proton decays were studied by p-gamma coincidence in combination with a He-jet tape transport system, and half-lives, proton energy spectra, gamma-transitions following the proton emission, as well as beta-delayed proton branching ratios to the low-lying states in the grand-daughter nuclei were determined. Comparing the experimental data with statistical model calculations, the ground-state spins of Tb-140 and Dy-141 were found to be consistent with 7 and 9/2, respectively. The configuration-constrained nuclear potential energy surfaces (NPES) of Tb-140 and Dy-141 were calculated using the Woods-Saxon-Strutinsky method, which suggest the ground-state spins and parities of Tb-140 and Dy-141 to be 7(+) and 9/2(-), respectively. In addition, the configuration-constrained NPES of Dy-143 were calculated, which predict a 1/2(+) ground state and a 11/2(-) isomer with excitation energy of 198 keV. These findings are consistent with our previous experimental data on Dy-143 reported in Eur. Phys. J. A 16, 347 (2003).

Discovery of Highly Excited Long-Lived Isomers in Neutron-Rich Hafnium and Tantalum Isotopes through Direct Mass Measurements

A study of cooled Au-197 projectile-fragmentation products has been performed with a storage ring. This has enabled metastable nuclear excitations with energies up to 3 MeV, and half-lives extending to minutes or longer, to be identified in the neutron-rich nuclides Hf-183,Hf-184,Hf-186 and Ta-186,Ta-187. The results support the prediction of a strongly favored isomer region near neutron number 116.

Measurement of the inelastic branch of the stellar O-14(alpha,p)F-17 reaction occurring in the explosive burning in Novae and X-ray busters

The inelastic component of the key astrophysical resonance (1(-), E-x=6.15 MeV) in the O-14(alpha,p)F-17 reaction has been studied by using the resonant scattering of F-17+p. The experiment was done at REX-ISOLDE CERN with the Miniball setup. The thick target method in inverse kinematics was utilized in the present experiment where a 44.2 MeV F-17 beam bombarded a similar to 40 mu m thick (CH2)(n) target. The inelastic scattering protons in coincidence with the de-excited 495 keV gamma rays have been clearly seen and they are from the inelastic branch to the first excited state in F-17 following decay of the 1(-) resonance in Ne-18. Some preliminary results are reported.

缺中子核素133Sm、133Pr和93Pd的衰变

本硕士沦文籍助兰州重离子加速器国家实验室分离扇聚焦回旋加速器（SFC）提供的重离子束通过全融合蒸发反应产生远离口稳定线的缺中子核素，并用本课题组发展和建立的氦喷嘴快速带传输系统以及多重符合测量装置分离、测量核素来研究其衰变性质。在实验准备期间，曾采用~(252)Cf源进行了氦喷嘴（I－I eje咧央速带传输系统效率的测定。给出了PbI_2，PbCl_2，NaCl三种无机欲添加剂的传输效率，以及传输效率随目标核质量变化的初步结果。而后完成了以下两项物理实验：~(113)Sm的（EC＋β~+）衰变纲图和133Pr的同核异能态的研究：用SFC引出的~(40)Ca~(12+)束流轰击96%Ru的浓缩同位素靶，采用氦喷嘴带传输系统和x-γ与γ-γ符合测量方法，首次建议了~(133)Sm的简单的（EC＋β~+）衰变纲图并测得了其β衰变半衰期。~(133)Sm是目前发表过（EC＋β~+）衰变纲图的最轻的钐（Sm的缺中子核。由于Ru靶中含有~(98-102)Ru的成分，同时产生了~(133)Pr，并首次测定了~(133)Pr 11／2~－同核异能态的寿命为（l.1±0.2）s。为Pr奇A核11／2~-同核异能态的数据作了重要的补充，汇编成Pr奇A核的11／2一同核异能态和与之相关的3／2~＋，5／2~+和7／2~+能级的系统性数据。用单粒子模型理论拟合从中提取了~(131,133,135,137)Pr的11／2~-同核异能态的约化跃迁概率的实验值，并与Weisskopf近似估计进行了比较。2.~(93)Pd的β缓发质子衰变：通过~(58)Ni（~(40)Ca，3n2p）反应合成β缓发质了先驱核~(93)Pd，采用氦喷嘴带传输系统加p-γ符合观测到了它的β缓发质子衰李，测得其半衰期为1.3±0.2s。采用统计模型计算拟合了实验测得的口缓发质子能谱和布居到质子发射体子核不同终态的分支比，首次由实验数据出发初步指认了93Pd的基态自旋-宇称为9／2~±。同时与采用Woods-Saxon Strutinsky方法计算~(93)Pd的核位能面得到的结果进行了比较。计算结果支持对~(93)Pd基态自旋一宇称为9／2~+的实验指认。

17B的实验研究

核反应总截面是描述原子核反应基本特征的一个重要的物理量，从中可以得到有关核反应、核结构和核内核子分布的信息。利用透射法测量核的反应总截面对于模型没有依赖性，因而得到的结果更加可靠。在兰州放射性束流线（RIBLL）上利用透射法测量了17B与C、Pb靶的反应，得到了17B与C、Pb的反应总截面和去除双中子截面，同时首次尝试用CLOVER探测器测量与碎片符合的γ能谱。利用半经验的Shen公式可以很好地拟合稳定核的反应总截面的实验结果，但是并不能很好地描述17B的实验结果，说明17B具有奇异结构。采用描述不稳定核的多种密度分布形式代入零力程的Glauber模型计算17B与C的反应总截面，并与实验结果进行了比较。发现采用Skyrme－Hatree－Fock（SHF）、双Gauss、Gauss＋HO计算的密度分布形式都能够很好地拟合整个能区内的实验结果。通过各种密度分布形式提取了17B的核子密度分布，发现17B的中子密度分布有很大的弥散，并证实了17B是由核芯15B加两个价中子组成的晕结构。将Skyrme－Hatree－Fock（SHF）、双Gauss、Gauss＋HO密度分布形式，输入Glauber模型与实验结果比较，提取了17B的物质均方根半径，不同密度分布提取的均方根半径值在实验误差范围内一致，也进一步验证了17B的晕结构。采用Woods－Saxon势来描述17B核外的价中子在核芯中形成的势场，通过解薛定鄂方程来求解价中子处于特定轨道的波函数。假设17B核外的价中子处于纯的s分波和d分波都不能很好地和实验结果符合。所以认为核外的价中子应该是混合组态，通过拟合实验结果求解出s分波谱学因子的值，证明核外的价中子处在2s1/2轨道的几率更大

中子核和铅区核的结构研究

我们首先用Woods-Saxon势对一些丰中子核进行了系统的计算．计算表明在Woods-Saxon势中考虑一个对称能项，Woods-Saxon势就能够很好的描述丰中子核的密度分布，单粒子能级结构和中子质子的均方根半径．用Woods Saxon势的计算结果表明中子皮是丰中子远离β稳定线核的普遍现象。2S1/2轨道与1d 5/2轨道的交又和2s1d壳与1p壳的壳崩渍是中子晕形成的重要原因，也是中子晕与中子皮的一个重要区别．壳模型的计算能够很好的再现9《A《14和3《Z《5丰中子核的许多性质，这表明了，改进壳模型的有效相互作用，壳模型可能能够描述远离核的性质． 我们208Ti一类核和206Pb的一些性质进行了系统的壳模型计算．计算结果表明，K-H和SDI等有效相互作用对描述208Ti一类核和206Pb的高激发态仍然是有效的，计算结果也表明，如果208Hg可供利用的β衰变能比206Hg小，则可以预计208Hg的半寿命比206Hg要长.计算还证实了在反应209Bi（ρ，a )206Pb中激发的206Pb激发态结构，与205Tl低激发态结构相似，即这些态可以用h9/2轨道上的一个质子与205T1的低激发态的弱耦合来描述，此即所谓的对应的相似多重态的概念． 最后，我们对11Li等中子晕核的束缚机制提出了一种新的关联机制和讨论了用壳模型描述集体运动的方法．

Carbono da biomassa microbiana em solos de cerrado: comparacao dos metodos fumigacao-incubacao e fumigacao-extracao.

Dentre os metodos mais utilizados para determinacao do carbono da biomassa microbiana destacam-se: os de cloroformio-fumigacao-incubacao (CFI) e cloroformio-fumigacao-extracao (CFE). Trabalhos relatados na literatura tem comparado a eficiencia desses metodos em diversos locais. No entanto, para a regiao do cerrado nao existem informacoes a esse respeito. O objetivo deste trabalho foi avaliar a eficiencia dos metodos CFE e CFI na determinacao do carbono da biomassa microbiana do solo (CBMS) em areas de cerrado sob cultura anual (rotacao soja-milho) e pastagem consorciada (Andropogon gayanus e Stylosanthes guianensis) e sob tres fitofisionomias - Mata de Galeria, Campo Sujo e Cerradao. Amostras de solo coletadas em duas profundidades, 0 a 5 cm e 5 a 20 cm, foram analisadas em quatro epocas: agosto de 1998, janeiro a agosto de 1999 e janeiro de 2000. Nas areas cultivadas, os resultados obtidos com os metodos CFE e CFI foram semelhantes independentemente dos tratamentos e das epocas amostradas; as pastagens consorciadas apresentaram maiores teores de CBMS do que as areas sob culturas anuais. A integracao profundidades x metodos foi significatica. Nao houve diferencas entre a profundidade 0 a 5 cm quando se utilizou o metodo CFI, mas as diferencas obtidas com o metodo CFE foram significativas. Os metodos CFI e CFE apresentaram as mesmas tendencias nas areas ativas, independentemente dos tratamentos, profundidades ou epocas analisados; a Mata de Galeria apresentou niveis de CBMS superiores aos do Cerradao e do Campo Sujo. As interacoes profundidades x metodos e epocas x metodos foram significativas devido ao fato de que as diferencas nos teores do carbono da bimassa microbiana, nas profundidades e epocas amostradas, foram mais acentuadas com o metodo CFE. Os resultados indicaram que os metodos CFI e CFE foram apropriados para determinacao da CBMS em solos de Cerrado sob cultivo e sob vegetacao nativa.

from Webern to dance to Burton.

Commissioned by the Concorde Ensemble. Paul Roe gave the premiere performance at the RHA Gallery, Dublin, 23rd February 2014. The piece is informed by the choreography of Jiri Kylian, in particular two three minute sections of his work No More Play initially choreographed to a score by Webern (his Five Movements for String Quartet) hence the title.

Hugh Blaker: Doing his Bit for the Moderns

Meyrick, Robert, 'Hugh Blaker: Doing his Bit for the Moderns', Journal of the History of Collections (2004) 16(2):173-189 RAE2008

Gwilym Prichard: A Retrospective

To accompany exhibition curated by Robert Meyrick, 'Gwilym Prichard', National Library of Wales; Oriel Theatr Clwyd; Oriel Plas Glyn-y-Weddw; Graham Sutherland Gallery, Picton Castle. pp.103

Giving and Receiving: Nuruddin Farah's Gifts, or, the Postcolonial Logic of Third World Aid

Woods, T. (2003). Giving and Receiving: Nuruddin Farah's Gifts, or, the Postcolonial Logic of Third World Aid. Journal of Commonwealth Literature, 38 (1), 91-112.

The Poetics of the Limit : Ethics and Politics in Modern and Contemporary American Poetry

Woods, Timothy, The Poetics of the Limit (New York: Palgrave Macmillan, 2003) RAE2008

'Preferring the wrong way': Mapping the Ethical Diversity of US Twentieth-Century Poetry

Woods, T. (2006). 'Preferring the wrong way': Mapping the Ethical Diversity of US Twentieth-Century Poetry. In C. Bigsby (Ed.), The Cambridge Companion to Modern American Culture (pp.450-468). Cambridge: Cambridge University Press. RAE2008

African Pasts: Memory and History in African Literatures

Woods, T. (2007). African Pasts: Memory and History in African Literatures. Manchetser: Manchester University Press. RAE2008