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排序方式: 共有590条查询结果,搜索用时 31 毫秒
41.
Zegers RG Sumihama M Ahn DS Ahn JK Akimune H Asano Y Chang WC Daté S Ejiri H Fujimura H Fujiwara M Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kohri H Kumagai N Makino S Matsumura T Matsuoka N Mibe T Miwa K Miyabe M Miyachi Y Morita M Muramatsu N Nakano T Niiyama M Nomachi M Ohashi Y Ooba T Ohkuma H Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu H Sugaya Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T Yoshimura M Yosoi M 《Physical review letters》2003,91(9):092001
Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献
42.
Kimura M Sakaguchi A Ohta K Hanabusa K Shirai H Kobayashi N 《Inorganic chemistry》2003,42(9):2821-2823
A new class of sterically hindered phthalocyanine has been synthesized and characterized. Pentaphenylbenzene units were introduced at the periphery of each phthalocyanine to yield a sterically protected metal center. The attachment of the bulky oligophenylbenzene units resulted in the complete isolation of individual MPc molecules. The pockets around a cobalt center affect selectivity in the ligation of pyridines that have different sizes and shapes. 相似文献
43.
Bearden IG Bøggild H Boissevain J Christiansen PH Conin L Dodd J Erazmus B Esumi S Fabjan CW Ferenc D Franz A Gaardhøje JJ Hansen AG Hansen O Hardtke D van Hecke H Holzer EB Humanic TJ Hummel P Jacak BV Kaimi K Kaneta M Kohama T Kopytine M Leltchouk M Ljubicic A Lörstad B Maeda N Martin L Medvedev A Murray M Ohnishi H Paic G Pandey SU Piuz F Pluta J Polychronakos V Potekhin M Poulard G Reichhold D Sakaguchi A Schmidt-Sørensen J Simon-Gillo J Sondheim W Sugitate T Sullivan JP Sumi Y Willis WJ 《Physical review letters》2001,87(11):112301
Two-particle interferometry of positive kaons is studied in Pb+Pb collisions at mean transverse momenta
approximately 0.25 and 0.91 GeV/c. A three-dimensional analysis was applied to the lower p(T) data, while a two-dimensional analysis was used for the higher p(T) data. We find that the source-size parameters are consistent with the m(T) scaling curve observed in pion-correlation measurements in the same collisions, and that the duration time of kaon emission is consistent with zero within the experimental sensitivity. 相似文献
44.
Doke T Hayashi T Kikuchi J Sakaguchi T Terasawa K Yoshihira E Nagaoka S Nakano T Takahashi S 《Radiation measurements》2001,33(3):373-387
Dosimetric measurements on the Space Shuttle Missions STS-84, -89 and -91 have been made by the real-time radiation monitoring device III (RRMD-III). Simultaneously, another dosimetry measurement was made by the Dosimetry Telescope (DOSTEL) on STS-84 and by the tissue-equivalent proportional counter (TEPC) on STS-91. First, the RRMD-III instrument is described in detail and its results summarized. Then, the results of DOSTEL and TEPC are compared with those of the RRMD-III. Also, the absorbed doses obtained by TLD (Mg2SiO4) and by RRMD-III on board STS-84 and -91 are compared. 相似文献
45.
T. Uesaka T. Wakui S. Sakaguchi T. Kawahara H. Sakai 《The European physical journal. Special topics》2007,150(1):71-74
We have constructed a polarized proton solid target system for
radioactive nuclear beam experiments at the Center for Nuclear Study,
the University of Tokyo. The proton polarization is based on an electron
population difference in a photo-excited triplet state of pentacene
molecule. The target system was completed in 2003 and applied to a
RI beam experiment in 2003 and 2005 by using the projectile fragment
separator, RIPS at RIKEN. The maximum polarization reached
20% under the condition of T=100 K and B=0.09 T.
Overview of the polarized target and its application in physics
experiments at RIPS and RIBF of RIKEN are presented. 相似文献
46.
H. Mardanpour H. R. Amir-Ahmadi A. Deltuva K. Itoh N. Kalantar-Nayestanaki T. Kawabata H. Kuboki Y. Maeda J. G. Messchendorp S. Sakaguchi H. Sakai N. Sakamoto Y. Sasamoto M. Sasano K. Sekiguchi K. Suda Y. Takahashi T. Uesaka H. Witała K. Yako 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):383-391
High-precision vector and tensor analyzing powers of elastic deuteron-proton ( d + p) scattering have been measured at intermediate energies to investigate effects of three-nucleon forces. Angular distributions
in the range of 70°-120° in the center-of mass frame for incident-deuteron energies E
d
lab = 130 and 180 MeV were obtained using the RIKEN facility. The beam polarization was unambiguously determined by measuring
the ^12C (d, α)^10B(2+) reaction at 0°. Results of the measurements are compared with state-of-the-art three-nucleon calculations. The present modeling of nucleon-nucleon
forces and its extension to the three-nucleon system is not sufficient to describe the high-precision data consistently and
requires, therefore, further investigation. 相似文献
47.
Natural-based plasticizers and biopolymer films: A review 总被引:2,自引:0,他引:2
Melissa Gurgel Adeodato Vieira Mariana Altenhofen da Silva Lucielen Oliveira dos Santos Marisa Masumi Beppu 《European Polymer Journal》2011,(3):254-263
In recent years, much attention has been focused on research to replace petroleum-based commodity plastics, in a cost-effective manner, with biodegradable materials offering competitive mechanical properties. Biopolymers have been considered as the most promising materials for this purpose. However, they generally present poor mechanical properties regarding processability and end-use application, since the fragility and brittleness exhibited during thermoformation can limit their potential for application. In order to overcome this problem, plasticizers are added to provide the necessary workability to biopolymers. This class of products became more visible when biodegradable additives and plasticizers also became the focus of material scientists. The use of natural and/or biodegradable plasticizers, with low toxicity and good compatibility with several plastics, resins, rubber and elastomers in substitution of conventional plasticizers, such as phthalates and other synthetic conventional plasticizers attracted the market along with the increasing worldwide trend towards use of biopolymers. Here we discuss the main results and developments in natural plasticizer/synthetic and biopolymer-based films during the last decades. 相似文献
48.
Masumi Torii Yuki Hitora Hikaru Kato Yuhei Koyanagi Teppei Kawahara Fitje Losung Remy E.P. Mangindaan Sachiko Tsukamoto 《Tetrahedron》2018,74(52):7516-7521
Four new sulfonated serinol derivatives, siladenoserinols M–P (1–4), were isolated from a tunicate of the family Didemnidae collected in Indonesia. Their chemical structures were elucidated by the interpretation of NMR and mass spectroscopic data. Two of them (2 and 4) were revealed to be disulfonate serinol derivatives, and the others were monosulfonates. Siladenoserinols A (5) and B (6), which we previously isolated from the same tunicate, inhibited the p53–Hdm2 interaction with an IC50 value of 2.0?μM. However, 1–4 did not inhibit the activity. The result suggested that the acetyl group in the bicyclic ketal unit and/or the glycerophospholipid moiety in 5 and 6 were responsible for the inhibition of the p53–Hdm2 interaction. 相似文献
49.
50.
We consider a convex polygonal heat conductor whose inscribed circle touches every side of the conductor. Initially, the conductor
has constant temperature and, at every time, the temperature of its boundary is kept at zero. The hot spot is the point at
which temperature attains its maximum at each given time. It is proved that, if the hot spot is stationary, then the conductor
must satisfy two geometric conditions. In particular, we prove that these geometric conditions yield some symmetries provided
the conductor is either pentagonal or hexagonal.
This research was partially supported by Grants-in-Aid for Scientific Research (B) (# 12440042) and (B) (# 15340047) of Japan
Society for the Promotion of Science, and by a Grant of the Italian MURST. 相似文献