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91.
在用82Se束流和天然Ba靶之间的深部非弹反应研究类靶余核激发态时,Ba靶严重氧化,88Sr的激发态由16O与82Se之间的融合蒸发反应产生,通过对束γ谱学方法测量了88Sr的退激γ射线,提取了γ跃迁的DCO系数和角分布各向异性因子,对所有能级进行了自旋指定,在已知能级之上观测到了两个高自旋异性因子,对所有能级进行了自旋指定,在已知能级之上观测到了两个高自旋能级结构,自旋,激发能分别达到13h,8520KeV和12h,7909KeV,根据能级衰变特征和邻近N=50同中子素的能级结构系统性,对高自旋态的组态进行了讨论。γ 相似文献
92.
形变双奇核178Ir转动带能级的旋称反转 总被引:1,自引:0,他引:1
张玉虎 T.Hayakawa M.Oshima Y.Toh J.Katakura Y.Hatsukawa M.Matsuda N.Shinohara T.Ishii H.Kusakari M.Sugawara T.Komatsubara 《中国物理 C》2000,24(12):1123-1130
利用152Sm(31P,5nγ)178Ir反应产生并研究了双奇核178Ir的高自旋态.实验中进行了178Ir核的在束γ测量,包括γ射线的激发函数测量、X–γ和γ–γ符合测量.首次建立了双奇核178Ir基于πh9/2νi13/2和πh11/2νi13/2准粒子组态上的转动带能级纲图.发现在低自旋区,两个转动带能级均出现旋称反转.对此核区半退耦带的旋称反转作了简要的分析和讨论. 相似文献
93.
Kah Hin Low Sharifuddin Md. Zain Mhd. Radzi Abas 《International journal of environmental analytical chemistry》2013,93(10):1161-1175
This paper describes the development of a compromised single-stage microwave-assisted digestion condition for multi-element determination in fish samples by inductively coupled plasm: mass spectrometry using experimental designs. A Plackett–Burman design was carried out as a multivariate strategy to investigate the main effects of the following parameter on microwave-assisted nitric acid digestion: microwave irradiation time, ramp time, digestion temperature, microwave power limit and the addition of hydrogen peroxide or hydrochloric acid. The most significant microwave setting parameters (radiation time, ramp and temperature) were further evaluated by response surface methodology under Box–Behnken design, while others were kept constant. The influences of different parameters vary according to metal element, thus the working conditions were established as a compromise within optimum region found for each targeted element which ensures quantitative recoveries and time efficiency. The compromised conditions are: ramp to 185°C in 10.5?min then hold for 14.5?min with 1600W (50%) of microwave power, using reagent mixture composed of 2.5?mL nitric acid, 0.5?mL hydrochloric acid and 7.0?mL water. Good agreements were demonstrated between measured and certified values with respect to DORM-3, DOLT-4 and ECM-CE278 and this method was successfully applied for metals determination in tilapia tissues. 相似文献
94.
Synthetic methods for 3-azabicyclo[3.1.0]hex-2-enes and 4-carbonylpyrroles have been developed that use copper-mediated/catalyzed reactions of N-allyl/propargyl enamine carboxylates under an O(2) atmosphere and involve intramolecular cyclopropanation and carbooxygenation, respectively. These methodologies take advantage of orthogonal modes of chemical reactivity of readily available N-allyl/propargyl enamine carboxylates; the complementary pathways can be accessed by slight modification of the reaction conditions. 相似文献
95.
Y. Toh K. Okano A. Taniguchi S. Yamada Y. Kawase 《Zeitschrift für Physik A Hadrons and Nuclei》1996,354(1):345-346
Excited states in the neutron-rich doubly-odd nucleus78As have been identified for the first time by proton-γ and γ-γ coincidence measurements via the76Ge(α, pn) reaction at 32, 36, and 40 MeV beam energy. Four levels have been found to decay with lifetimes in the nanosecond region. The 5(+) to (10+) states are ascribed to the (πg 9/2?νg 9/2) intruder two-quasiparticle configuration with some collective components in the 9(+) and (10+) states. 相似文献
96.
利用能量为170MeV的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研究了188Tl的高自旋态能级结构.依据实验结果建立了188Tl基于πh9/2(?)vi13/2组态的转动带.根据双奇Tl核能级结构的相似性,指定了188Tlπh9/2(?)vi13/2扁椭球转动带的自旋值.结果表明在188Tl中,πh9/2(?)vi13/2扁椭球转动带在低自旋区具有旋称反转性质.利用包含了质子-中子剩余相互作用的准粒子-转子模型,定性地解释了πh9/2(?)vi13/2扁椭球转动带的低自旋区旋称反转现象. 相似文献
97.
X.H. Zhou M. Oshima Y. Toh Y.H. Zhang Y. Zheng M. Koizumi A. Osa T. Hayakawa Y. Hatsukawa T. Shizuma M. Sugawara 《The European Physical Journal A - Hadrons and Nuclei》2002,15(3):285-289
Based on the systematic investigation of the data available for nuclei with A≥ 40, a Z
1/3-dependence for the nuclear charge radii is shown to be superior to the generally accepted A
1/3 law. A delicate scattering of data around R
c/Z
1/3 is inferred as owing to the isospin effect and a linear dependence of R
c/Z
1/3 on N/Z (or (N - Z)/2) is found. This inference is well supported by the microscopic Relativistic Continuum Hartree-Bogoliubov (RCHB) calculation
conducted for the proton magic Ca, Ni, Zr, Sn and Pb isotopes including the exotic nuclei close to the neutron drip line.
With the linear isospin dependence provided by the data and RCHB theory, a new isospin-dependent Z
1/3 formula for the nuclear charge radii is proposed.
Received: 23 September 2001 / Accepted: 21 January 2002 相似文献
98.
99.
M. Oshima Y. Toh Y. Hatsukawa M. Koizumi A. Kimura A. Haraga M. Ebihara K. Sushida 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):257-262
A new radionuclide quantification method is proposed on the basis of multiple gamma-ray detection, which is two or higher
fold gamma-ray coincidence method. The coincidence method has so far been used for nuclear structure study. We apply this
method for quantification of radioactive nuclei. The advantage of this method consists of high energy resolution and high
sensitivity. It is successfully applied to nuclear waste analysis, neutron activation analysis and prompt gamma-ray analysis.
The principle of the multiple gamma-ray detection method and future perspectives for an innovative pulsed neutron source and
a new detector system will be presented. 相似文献
100.
Development of a neutron beam line and detector system for multiple prompt gamma-ray analysis 总被引:1,自引:1,他引:0
Y. Toh M. Oshima K. Furutaka A. Kimura M. Koizumi Y. Hatsukawa J. Goto 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(3):703-706
A neutron beam line for multiple prompt gamma-ray analysis was constructed at the Japan Atomic Energy Agency. A detector system
for the MPGA was constructed at the C2-3-2 beam line in January 2005. It comprised eight (upgraded in March 2007) clover Ge
detectors with a BGO Compton suppressor. High efficiency detector system provides an advantage in terms of the detection limit
of MPGA when compared to the result of PGA. The supermirror neutron bender was improved and a supermirror neutron guide was
installed upstream of the sample position. 相似文献