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551.
Yuki Takebayashi Takuya Konno Shouhei Shimada Fumiaki Miyamaru John C. Young Hideaki Kitahara Keisuke Takano Masanori Hangyo Takehito Suzuki 《Applied Physics A: Materials Science & Processing》2014,115(2):501-508
This paper presents the design and fabrication of an artificial multilayer lens comprising ten layers of metal rectangular chips on a cyclo olefin polymer, which has low loss in the terahertz band. Measurements of the focusing effect are also presented. The focusing effect is produced by the rectangular metallic chips which act as an electrical dipole. Simulations are performed using ANSYS HFSS. The lenses are fabricated by laser processing or semiconductor etching. The focusing effect is confirmed by measurement using terahertz near-field microscopy, although some discrepancies are observed between the simulated and measured results. 相似文献
552.
Nishimura S Li Z Watanabe H Yoshinaga K Sumikama T Tachibana T Yamaguchi K Kurata-Nishimura M Lorusso G Miyashita Y Odahara A Baba H Berryman JS Blasi N Bracco A Camera F Chiba J Doornenbal P Go S Hashimoto T Hayakawa S Hinke C Ideguchi E Isobe T Ito Y Jenkins DG Kawada Y Kobayashi N Kondo Y Krücken R Kubono S Nakano T Ong HJ Ota S Podolyák Z Sakurai H Scheit H Steiger K Steppenbeck D Sugimoto K Takano S Takashima A Tajiri K Teranishi T Wakabayashi Y Walker PM Wieland O Yamaguchi H 《Physical review letters》2011,106(5):052502
The β-decay half-lives of 38 neutron-rich isotopes from (36)Kr to (43)Tc have been measured; the half-lives of (100)Kr, (103-105)Sr, (106-108)Y, (108-110)Zr, (111,112)Nb, (112-115)Mo, and (116,117)Tc are reported here. The results when compared with previous standard models indicate an overestimation in the predicted half-lives by a factor of 2 or more in the A≈110 region. A revised model based on the second generation gross theory of β decay better predicts the measured half-lives and suggests a more rapid flow of the rapid neutron-capture process (r-matter flow) through this region than previously predicted. 相似文献
553.
H. Okazaki T. Arakane T. Sato T. Wakita M. Hirai Y. Takano S. Iriyama T. Yokoya 《Journal of Physics and Chemistry of Solids》2011,72(5):582-584
We studied the electronic structure evolution of heavily B-doped diamond films across the metal-insulator transition (MIT) using ultraviolet photoemission spectroscopy (UPS). From high-temperature UPS, through which electronic states near the Fermi level (EF) up to ∼5kBT can be observed (kB is the Boltzmann constant and T the temperature), we observed the carrier concentration dependence of spectral shapes near EF. Using another carrier concentration dependent UPS, we found that the change in energy position of sp-band of the diamond valence band, which corresponds to the shift of EF, can be explained by the degenerate semiconductor model, indicating that the diamond valence band is responsible for the metallic states for samples with concentrations above MIT. We discuss a possible electronic structure evolution across MIT. 相似文献
554.
555.
Hayashi N Yamamoto T Kageyama H Nishi M Watanabe Y Kawakami T Matsushita Y Fujimori A Takano M 《Angewandte Chemie (International ed. in English)》2011,50(52):12547-12550
Magnetic attraction: The cubic perovskite BaFeO(3) (see picture, Ba?blue, Fe?brown, O?white), which is obtained by a low-temperature reaction using ozone as an oxidant, exhibits ferromagnetism with a fairly large moment of 3.5?μ(B) per Fe ion above a small critical field of approximately 0.3?T. This specific ferromagnetism is attributed to the enhancement of O→Fe charge transfer that arises from deepening of the Fe(4+) d levels. 相似文献
556.
557.
Ikebe J Umezawa K Kamiya N Sugihara T Yonezawa Y Takano Y Nakamura H Higo J 《Journal of computational chemistry》2011,32(7):1286-1297
Trivial trajectory parallelization of multicanonical molecular dynamics (TTP-McMD) explores the conformational space of a biological system with multiple short runs of McMD starting from various initial structures. This method simply connects (i.e., trivially parallelizes) the short trajectories and generates a long trajectory. First, we theoretically prove that the simple trajectory connection satisfies a detailed balance automatically. Thus, the resultant long trajectory is regarded as a single multicanonical trajectory. Second, we applied TTP-McMD to an alanine decapeptide with an all-atom model in explicit water to compute a free-energy landscape. The theory imposes two requirements on the multiple trajectories. We have demonstrated that TTP-McMD naturally satisfies the requirements. The TTP-McMD produces the free-energy landscape considerably faster than a single-run McMD does. We quantitatively showed that the accuracy of the computed landscape increases with increasing the number of multiple runs. Generally, the free-energy landscape of a large biological system is unknown a priori. The current method is suitable for conformational sampling of such a large system to reduce the waiting time to obtain a canonical ensemble statistically reliable. 相似文献
558.
Yukiko Enomoto-Rogers Hiroshi Kamitakahara Arata Yoshinaga Toshiyuki Takano 《Cellulose (London, England)》2011,18(4):929-936
Cellulose chains bearing N-lipoyl group at the reducing-end as a sulfide linker, self-assembled on the surface of gold nanoparticles (CELL2Au, CELL13Au,
and CELL41Au with the number average degrees of polymerization (DPn) of 2, 13, and 41, respectively) were prepared. CELL2Au, CELL13Au, and CELL41Au were obtained via deprotection of the cellulose
triacetate (CTA) self-assembled on the surface of gold nanoparticles that are consisting of CTA chains with corresponding
DPn organized in a radial manner with head-to-tail orientation, where a head is the reducing-end, and a tail is the non-reducing-end.
CELL2Au and CELL13Au were well-dispersed in water including a trace of methanol, whereas CELL41Au was not. The transmission
electron microscopy (TEM) observation of CELLAus deposited on copper grids revealed that the diameters (d) of the gold cores of CELL2Au, CELL13Au, and CELL41Au were 6.1, 6.1, and 11.5 nm, respectively. Wide angle X-ray diffractgram
showed that cellulose chains of CELL13Au had quite low crystallinity and exhibited additional faint diffraction pattern of
cellulose II. Cellulose chains of CELL41Au were amorphous. The UV–vis measurements revealed that CELL2Au and CELL13Au were
well-dispersed in water. The hydrodynamic diameters (D) of CELL2Au and CELL13Au in water were 21.8 and 55.9 nm, respectively, according to dynamic light scattering (DLS) measurements,
suggesting that cellulose chains on the gold were organized in a radial manner with head-to-tail orientation. 1H-NMR measurement revealed that low-molecular-weight cellulose chains (DPn = 13) on the gold dissolved in water, whereas low-molecular-weight cellulose (DPn = 13) itself did not. 相似文献
559.
Kenichi Takano Lijie GuanYuchen Zhou Yue LiuJoe Smyth Moris Dovek 《Journal of magnetism and magnetic materials》2008
As the magnetic moment of soft under layer (SUL) decreases, the magnetic saturation during the write process becomes severe. It induces some partial erasures in the media write pattern and results in poor write performance such as an output roll-off and signal-to-noise ratio degradation. This erasure is due to the head field longitudinal component at the write gap after the transition writing in the trailing shielded pole perpendicular recording head. In case the SUL has low magnetic moment and high write current is inputted, erasure bubble appears next to the write bubble because the head field perpendicular component switches from positive to negative in the polarity. But the erasure appears even without the negative perpendicular field, and the longitudinal head field of the write gap is dominant for the erasure. 相似文献