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81.
This paper explores the feasible use of circular optical grating for measuring the rotation of mirrors that are commonly found in micro-systems. Both theoretical and experimental results show that distortion of the circular grating that is projected onto the mirror surface is a simple function of the angular rotation of the mirror. The circular grating may readily be generated using a standard Michelson interferometer or an LCD projector. Through manipulating the distance between the interferometer and the mirror surface, the diameter of the optical grating may be varied. Furthermore, the additional use of a converging lens enables a significant reduction in the size of the grating: with simple laboratory facility, small circular grating of about 400 μm is achieved for use on micro-systems. With the use of more sophisticated optical elements, the angular rotation of even smaller micro-mirrors may be measured. 相似文献
82.
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
83.
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
84.
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
85.
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
86.
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
87.
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
88.
89.
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
90.
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