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91.
K.A. Schmidt M. Bergström G.B. Hagemann B. Herskind G. Sletten P.G. Varmette J. Domscheit H. Hübel S.W. Ødegård S. Frattini A. Bracco B. Million M.P. Carpenter R.V.F. Janssens T.L. Khoo T. Lauritsen C.J. Lister S. Siem I. Wiedenhöver D.J. Hartley L.L. Riedinger A. Maj W.C. Ma R. Terry 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):15-28
High-spin properties of the nucleus 169Hf have been studied through the fusion evaporation reaction 96Zr(76Ge,3n)169Hf at a beam energy of 310 MeV. The known rotational bands have been extended considerably and 6 new bands have been established,
four of which form coupled bands with pronounced M1 connections. Quasiparticle assignments are suggested for the new band structures, and it appears that coupling to vibrational
degrees of freedom plays a role. Both coupled bands involve the excitation of quasiprotons. In the region of highest spin,
a large alignment gain is interpreted in terms of a mixed crossing where an h
9/2 and an h
11/2 quasiproton provide the two signatures of the aligning configuration.
Received: 23 March 2001 / Accepted: 20 September 2001 相似文献
92.
This paper discusses the application of the developed analytical method (Reji George, Jain, Pradhan, A.S., 2008. Theoretical evaluation of dose distribution in product in radiation processing plants. Radiat. Phys. Chem. 77, 186–191), for determining the activity loading pattern in a radiation processing plant to get the desired dose uniformity ratio (DUR) for processing mangoes and how the method was used to evaluate the expected source utilization efficiency for the redesigned source–product configuration. 相似文献
93.
Multistage Interconnection Networks (MINs) are network systems providing fast and efficient communications at a reasonable cost. A gamma network is a specific class of MINs, which provides redundant paths in the system. In a gamma network, information from source nodes is transmitted through a specific set of routes to destination nodes. Reliability of an MIN is used as a measure of system’s ability to transform information from input to output devices. Due to the complexity of network configuration and availability of redundant paths, reliability bounds to estimate the exact reliability of a gamma network is proposed. A numerical example of an 8 × 8 gamma network is presented to demonstrate the accuracy of the reliability bounds. When the lower bound reliability provides sufficient assurance that the system will be operational at some specified time and closely approximates the exact reliability, then no further effort for obtaining the exact reliability expression is necessary. 相似文献
94.
M. -G. Porquet Ts. Venkova A. Astier I. Deloncle A. Prévost F. Azaiez A. Buta D. Curien O. Dorvaux G. Duchêne B. J. P. Gall F. Khalfallah I. Piqueras M. Rousseau M. Meyer N. Redon O. Stézowski R. Lucas A. Bogachev 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):153-159
The 87Kr nucleus has been produced as fission fragment in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. High-spin states of this neutron-rich isotope have been
identified for the first time. Its level scheme has been obtained up to 6.3MeV excitation energy and spin I ∼ 23/2ℏ. Its structure is interpreted by analogy with those of the heavier isotones. The proposed configurations involve
both proton and neutron excitations from several sub-shells located close to the Fermi levels, particularly νd5/2, πp3/2f5/2 and πg9/2. Moreover, a revised spin value of 5/2- for the 87Br ground state is proposed. 相似文献
95.
The influence of gamma radiation on the dielectric relaxation behaviour of isotactic polypropylene: The α relaxation 总被引:1,自引:0,他引:1
The high-temperature α relaxation in gamma irradiated isotactic polypropylene (iPP) was studied over the temperature (298-406 K), frequency (103-106 Hz) and absorbed dose (0-700 kGy) ranges by means of dielectric spectroscopy. The multiple α relaxation was resolved from the β relaxation by curve fitting and its parameters were determined. Its position, intensity and activation energy were found to be strongly dependent on the changes in the structural and morphological parameters attributed to the exposure of the samples to radiation. Wide angle X-ray diffraction (WAXD) was used to investigate radiation-induced changes in the crystalline structure and degree of crystallinity, since this relaxation is connected with the crystal phase. Infrared (IR) spectroscopy and gel measurements were used to determine the changes in the oxidative degradation and the degree of network formation, respectively; the polar (carbonyl and/or hydroperoxide) groups that were introduced by irradiation were considered as tracer groups. Conclusions derived according to different methods were compared. The results reveal uncommon α relaxation behaviour with gamma radiation and confirm the multiple nature of this process, together with high dielectric and/or relaxation sensitivity of iPP to the radiation-induced changes. 相似文献
96.
Lin J Griffin RG Khaneja N 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,212(2):402-411
The paper describes two-dimensional solid state NMR experiments that use powdered dephased antiphase coherence (γ preparation) to encode chemical shifts in the indirect dimension. Both components of this chemical shift encoded gamma-prepared states can be refocused into inphase coherence by a recoupling element. This helps to achieve sensitivity enhancement in 2D NMR experiments by quadrature detection. The powder dependence of the gamma-prepared states allows for manipulating them by suitable insertion of delays in the recoupling periods. This helps to design experiments that suppress diagonal peaks in 2D spectra, leading to improved resolution. We describe some new phase modulated heteronuclear and homonuclear recoupling pulse sequences that simplify the implementation of the described experiments based on γ prepared states. Recoupling in the heteronuclear spin system is achieved by matching the difference in the amplitude of the sine/cosine modulated phase on the two rf-channels to the spinning frequency while maintaining the same power on the two rf-channels. 相似文献
97.
一般寿命分布和定时截尾的Bayes变量抽样方案 总被引:2,自引:0,他引:2
林(1994)研究了指数分布和定时截尾的变量抽样方案.本文将讨论一般寿命分布和定时截尾的一次抽样方案.在多项式损失函数的假设下,我们讨论了Weibull分布、双参数指数分布和-分布三种情形,并着重讨论Weibull分布的情形.本文还提出了一个可用于近似地确定最优抽样方案的有报算法,并且进行了灵敏度分析,还同林较早的模型(1990,1994)做了比较. 相似文献
98.
We describe the optimisation of RadLine®; a small, real time, remotely operated radiation detector, which consists of an inorganic scintillation crystal coupled to a fibre optic cable transporting produced photons to a CCD camera some distance away. RadLine® is tested in a beta and gamma narrow radiation field of 2.4 GBq, from a Caesium-137 (662 KeV) source, at doses rates between 0.125 mSvhr−1 and 10 mSvhr−1. Our results establish that the lower limit of the device corresponds to a dose rate of 0.2 mSvhr−1, constrained by the signal to noise ratio of the instrument. We also demonstrate the process of characterising the RadLine® for utilisation underwater due to its partial electrical inactiveness; and to consider how the instrument might perform in aquatic environments and ultimately in a First Generation Magnox Storage Ponds (FGMSP). The RadLine® brings a marked difference to actual underwater radiation monitoring devices such as; HPGe, CZT and GM detectors, which not only incorporate the whole electronics within and are more bulky, only perform over a short range. The RadLine®’s design offers signification value for intermediate (>100 m) and long range detection. 相似文献
99.
J. Cederkäll M. Lipoglavšek M. Palacz J. Persson J. Blomqvist A. Ataċ C. Fahlander H. Grawe A. Johnson W. Klamra J. Kownacki A. Likar L.–O. Norlin J. Nyberg R. Schubart D. Seweryniak G. de Angelis P. Bednarczyk Z. Dombrádi D. Foltescu M. Górska D. Jerrestam S. Juutinen E. Mäkelä B. M. G. Perez M. de Poli H. A. T. Shizuma Ö. Skeppstedt G. Sletten S. Törmänen 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):7-9
New excited states have been observed in the neutron deficient isotope 98Ag following the 58Ni+50Cr →108Te* heavy–ion reaction. One of these states may be interpreted as a maximum spin aligned state of the πg9/2
−3νg7/2 configuration. Other possible interpretations within the nuclear shell model are discussed as well.
Received: 24 October 1997 相似文献
100.