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101.
The characteristics of electron transmission through C70 molecule bridge in which two atomic chain leads are connected to long-axis carbon atoms are investigated theoretically by
using tight-binding approach based on the Green’s function with only one π orbital electron per carbon atom. Electron transmission
through C70 molecule from the input to the output terminal is obtained. From the spectrum, the switching feature of the electron transmission
through C70 is found, and the oscillation property based on the quantized level is explained. The quantum current distributions inside
C70 molecule bridge are calculated and simulated by the quantum current density theory based on Fisher-Lee formula at the energy
point E = −0.2 eV, where the transmission spectrum shows a peak. The maximum and the minimum bond quantum currents are presented,
and the reason why the currents are distributed nonuniformly is explained by the phase difference of the atomic orbits. The
result shows that the currents at each atomic site agree with Kirchhoff quantum current conservation law.
Supported by the National Key Basic Research Development Project (Grant No. 2003CB716204), the International Corporation Project
of the Education Department of China (Grant No. 20050360563), the Key Laboratory of Advanced Photonic and Electronic Materials
of Jiangsu (Grant No. BM2003202) and the State Key Laboratory of Solid State Microstructures of Nanjing University 相似文献
102.
M. Asai K. Tsukada S. Ichikawa M. Sakama H. Haba Y. Nagame I. Nishinaka K. Akiyama A. Toyoshima T. Kaneko Y. Oura Y. Kojima M. Shibata 《The European Physical Journal A - Hadrons and Nuclei》2003,16(1):17-19
A new neutron-deficient berkelium isotope 241Bk produced in the 239Pu(6Li, 4n) reaction has been identified using a gas-jet coupled on-line isotope separator. Cm K and L X-rays associated with the EC decay of 241Bk were observed in the mass-241 fraction, and three γ transitions were attributed to the EC decay of 241Bk through X-γ coincidences. The half-life of 241Bk was determined to be 4.6±0.4 min which is 1/2-1/4 of that of theoretical predictions. The half-life value and the observed
γ transitions can be consistently explained as a consequence of the allowed EC transition of π7/2+[633] → ν7/2+[624].
Received: 14 October 2002 / Accepted: 6 November 2002 / Published online: 17 January 2003
RID="a"
ID="a"e-mail: asai@tandem.tokai.jaeri.go.jp
Communicated by J. ?yst? 相似文献
103.
M. Asai M. Sakama K. Tsukada S. Ichikawa H. Haba I. Nishinaka Y. Nagame S. Goto Y. Kojima Y. Oura H. Nakahara M. Shibata K. Kawade 《The European Physical Journal A - Hadrons and Nuclei》2004,22(3):411-416
EC and decays of 235Am have been studied using a gas-jet coupled on-line isotope separator. Excited states in 235Pu have been established for the first time by means of -ray spectroscopy following the EC decay of 235Am. The deduced log ft value suggests that the ground state of 235Am should have the 5/2-[523] configuration. The - coincidence result has revealed that the 5/2-[523] state in 231Np populated by the favored transition of 235Am is located at < 15 keV, which allows us to precisely determine the Q value of 235Am. 相似文献
104.
105.
Toyoshima Atsushi Mitsukai Akina Tsukada Kazuaki Ooe Kazuhiro Haba Hiromitsu Komori Yukiko Murakami Masashi Kaneya Yusuke Sato Daisuke Asai Masato Sato Tetsuya K. Nagame Yuichiro 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):421-430
Journal of Radioanalytical and Nuclear Chemistry - We have studied extraction behavior of group-6 elements Mo and W to search for suitable conditions for an on-line extraction experiment of their... 相似文献
106.
Naofumi Nishida Yuuki Hori Akane Yamauchi Makoto Sakurai Hiroyuki A. Sakaue Daiji Kato 《X射线光谱测定》2020,49(1):74-77
The electron beam ion source (Kobe EBIS) has been developed to perform modification of surfaces using highly charged ions (HCIs) at the Kobe University, Japan. Recent study revealed that periodic intermission of electron beam improves charge state distribution of extracted ions. The period of intermission is in the order of 100 ms, and the width of beam-off time is 1 ms or less. This operational mode (pulse mode) makes it possible to produce Ar15+ to Ar17+ effectively, whereas the charge is limited less than 14+ under the ordinary operational mode with direct current (DC) electron beam. A spike of HCIs with a peak current in the order of nA is also observed at each moment of electron beam off. The measurement of the time evolution of Ar16+ intensity around the timing of mode change revealed that the intensity of extracted Ar16+ changes slowly after mode change with a time constant of few seconds. 相似文献
107.
Tanaka Kazuya Tani Yukinori Kozai Naofumi Ohnuki Toshihiko 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):1109-1114
Journal of Radioanalytical and Nuclear Chemistry - We investigated the sorption of Pu(IV) on biogenic Mn oxide, composed of Mn(IV) oxide and hyphae, produced by Mn(II)-oxidizing fungus. The... 相似文献
108.
Liu Jiang Dotsuta Yuma Sumita Takehiro Kitagaki Toru Ohnuki Toshihiko Kozai Naofumi 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2785-2794
Journal of Radioanalytical and Nuclear Chemistry - Remnant nuclear fuel debris in the damaged nuclear reactors at the Fukushima Daiichi Nuclear Power Plant (FDNPP) has contacted the groundwater... 相似文献
109.
K. Tsukada I. Nishinaka N. Shinohara S. Ichikawa Y. Nagame K. Sueki H. Nakahara T. Ohtsuki M. Tanikawa 《The European Physical Journal A - Hadrons and Nuclei》1998,2(2):153-155
Angular distributions of fission fragments with mass number A=97-159 have been measured by the radiochemical recoil-catcher
method in the proton-induced fission of 244Pu with the incident energy of 15 MeV. Angular anisotropies of extreme asymmetric mass division products even up to the fragment
mass ratio of A
H
/A
L
∼ 1.85 are found not any different from those of the typical asymmetric mass division products with A∼ 138, which indicates that no clear evidence is observed for the existence of an additional saddle point configuration in
the extreme asymmetric mass division. The correlation between the saddle point state evaluated from the angular anisotropy
and the mass division mode is discussed. 相似文献
110.
A single step on-line concentration and separation method for peptides in non-aqueous capillary electrophoresis was developed. ACN containing 50 mM tetraethylammonium perchlorate was used as the electrophoretic medium; angiotensins I-IV were separated as a result of the differences in the magnitudes of their interactions with perchlorate anions. When the sample solution (ACN containing 0.5% trifluoroacetic acid and angiotensins) was injected as a large-volume plug, the analytes were concentrated at the inlet end of the capillary by both sweeping and stacking mechanisms; the separation procedure then started automatically without any operations such as polarity change. It was found that the concentration of analytes, injection period, and concentration of tetraethylammonium perchlorate in the electrophoretic medium were important factors for both separation and concentration efficiencies. The angiotensins were concentrated and separated with the large-volume injection of up to 80% of the effective capillary length. 相似文献