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排序方式: 共有651条查询结果,搜索用时 390 毫秒
91.
H. Matsubara M. Takaki T. Uesaka S. Shimoura N. Aoi M. Dozono T. Fujii K. Hatanaka T. Hashimoto T. Kawabata S. Kawase K. Kisamori Y. Kikuch Y. Kubota C. S. Lee H. C. Lee Y. Maeda S. Michimasa K. Miki H. Miya S. Noji S. Ota S. Sakaguchi Y. Sasamoto T. Suzuki L. T. Tang K. Takahisa H. Tokieda A. Tamii K. Yako Y. Yasuda N. Yokota R. Yokoyama J. Zenihiro 《Few-Body Systems》2013,54(7-10):1433-1436
Spectroscopy for neutron-rich nuclei 9He and 12Be has been performed by means of heavy-ion double charge exchange (HIDCX) (18O, 18Ne) reaction on stable target nuclei 9Be and 12C, respectively. Several clear peaks in 12Be at low excitation energy region even above neutron separation energy have been observed in one-shot measurement, whereas no prominent signals of 9He have been observed owing to the small cross section. It is shown that the HIDCX reaction is a new powerful spectroscopic tool for study of unstable neutron-rich nuclei. 相似文献
92.
Y. Maeda T. Saito H. Miyasako T. Uesaka S. Ota S. Kawase T. Kikuchi H. Tokieda T. Kawabata K. Yako T. Wakasa S. Sakaguchi R. Chen H. Sakaguchi T. Shima T. Suzuki A. Tamii 《Few-Body Systems》2013,54(7-10):1311-1314
For the study of three nucleon force (3NF) effects in the intermediate energy region, the differential cross sections and the vector analyzing power A y were measured for the 2H(p, n) inclusive breakup reaction at 170 MeV. The polarized proton beam of 170 MeV was injected to the deuterated polyethylene (CD2) target and the energy of scattered neutrons were deduce by TOF method. The data was compared with the results of the Faddeev calculations with and without 3NFs. Concerning about the differential cross sections, we can see large discrepancies between the data and the calculations in the region where the energies of scattered neutrons are low, which are similar to the results of the 2H(p, p) inclusive breakup reaction at 250 MeV. 相似文献
93.
Zhaoma Shu Iku Tanaka Azumi Ota Daichi Fushihara Naoko Abe Saki Kawaguchi Kosuke Nakamoto Fumiaki Tomoike Seiichi Tada Yoshihiro Ito Yasuaki Kimura Hiroshi Abe 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6683-6687
Development of intracellular delivery methods for antisense DNA and siRNA is important. Previously reported methods using liposomes or receptor‐ligands take several hours or more to deliver oligonucleotides to the cytoplasm due to their retention in endosomes. Oligonucleotides modified with low molecular weight disulfide units at a terminus reach the cytoplasm 10 minutes after administration to cultured cells. This rapid cytoplasmic internalization of disulfide‐modified oligonucleotides suggests the existence of an uptake pathway other than endocytosis. Mechanistic analysis revealed that the modified oligonucleotides are efficiently internalized into the cytoplasm through disulfide exchange reactions with the thiol groups on the cellular surface. This approach solves several critical problems with the currently available methods for enhancing cellular uptake of oligonucleotides and may be an effective approach in the medicinal application of antisense DNA and siRNA. 相似文献
94.
Ihlefeld A Shinn-Cunningham B 《The Journal of the Acoustical Society of America》2008,123(6):4380-4392
When listening selectively to one talker in a two-talker environment, performance generally improves with spatial separation of the sources. The current study explores the role of spatial separation in divided listening, when listeners reported both of two simultaneous messages processed to have little spectral overlap (limiting "energetic masking" between the messages). One message was presented at a fixed level, while the other message level varied from equal to 40 dB less than that of the fixed-level message. Results demonstrate that spatial separation of the competing messages improved divided-listening performance. Most errors occurred because listeners failed to report the content of the less-intense talker. Moreover, performance generally improved as the broadband energy ratio of the variable-level to the fixed-level talker increased. The error patterns suggest that spatial separation improves the intelligibility of the less-intense talker by improving the ability to (1) hear portions of the signal that would otherwise be masked, (2) segregate the two talkers properly into separate perceptual streams, and (3) selectively focus attention on the less-intense talker. Spatial configuration did not noticeably affect the ability to report the more-intense talker, suggesting that it was processed differently than the less-intense talker, which was actively attended. 相似文献
95.
Asao Mizoguchi Shinji Ota Hideto Kanamori Yoshihiro Sumiyoshi Yasuki Endo 《Journal of Molecular Spectroscopy》2008,250(2):86-97
Pure rotational spectra of S235Cl2 and S235Cl37Cl have been observed using a Fourier-transform microwave spectrometer. An analysis of the hyperfine structure made by considering the nuclear spin statistics showed that S2Cl2 has C2symmetry, where the hyperfine splittings due to the two Cl nuclei were analyzed precisely. The nuclear quadrupole coupling constants including the off-diagonal (χab, χac, χbc) components and the nuclear spin–rotation interaction constants associated with the two Cl nuclei have been determined for the first time. We have shown that the nuclear quadrupole interaction plays an important role in the ortho–para mixing. 相似文献
96.
S. Ota S. Shimoura H. Iwasaki M. Kurokawa S. Michimasa N. Aoi H. Baba K. Demichi Z. Elekes T. Fukuchi T. Gomi S. Kanno S. Kubono K. Kurita H. Hasegawa E. Ideguchi N. Iwasa Y.U. Matsuyama K.L. Yurkewicz T. Minemura T. Motobayashi T. Murakami M. Notani A. Odahara A. Saito H. Sakurai E. Takeshita S. Takeuchi M. Tamaki T. Teranishi Y. Yanagisawa K. Yamada M. Ishihara 《Physics letters. [Part B]》2008
97.
In situ heating experiments using high-energy, high-intensity synchrotron radiation, can be successfully designed to study structural evolution with temperature of glassy materials. Coherent diffraction from glassy materials forms a succession of halos or diffraction maxima in reciprocal space and the variation with temperature, of the wave-vector Qmax or angular position of the first diffracted intensity I(Qmax) maximum below Tg can be used to determine the iso-structural volume expansion. In the present work we have obtained synchrotron X-ray diffraction patterns in transmission during in situ heating of a B2O3 glass. Samples were obtained by melting the B2O3 glass rods which were then air-cooled or liquid nitrogen-cooled. The evolution with temperature (and time) of the position of the first diffraction maximum of the diffraction pattern accurately reflected the thermal expansion coefficient and the relaxation behavior of the B2O3 glass. Such results allowed determination by diffraction of the glass transition temperature, Tg, at 580 K, as well as information on the structural relaxation during thermal annealing. The total volume changes due to relaxation were measured to be about 1.5 vol.% and 2.5 vol.%, for the air-cooled and the liquid nitrogen-cooled B2O3 glass, respectively. 相似文献
98.
99.
Takahiro Moriyama Daiki Mizukami Dr. Makoto Yoritate Dr. Kazuteru Usui Dr. Daisuke Takahashi Dr. Eisuke Ota Prof. Dr. Mikiko Sodeoka Prof. Dr. Tadashi Ueda Prof. Dr. Satoru Karasawa Prof. Dr. Go Hirai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(11):e202103925
Minimalist photo-reactive probes, which consist of a photo-reactive group and a tag for detection of target proteins, are useful tools in chemical biology. Although several diazirine-based and aryl azide-based minimalist probes are available, no keto-based minimalist probe has yet been reported. Here we describe minimalist probes based on a 2-thienyl-substituted α-ketoamide bearing an alkyne group on the thiophene ring. The 3-alkyne probe showed the highest photo-affinity labeling efficiency. 相似文献
100.
Johanna M. Spörl Antje Ota Ronald Beyer Thomas Lehr Alexandra Müller Frank Hermanutz Michael R. Buchmeiser 《Journal of polymer science. Part A, Polymer chemistry》2014,52(9):1322-1333
Reversible‐addition fragmentation‐transfer (RAFT) polymerization of acrylonitrile (AN) was performed with 2‐(2‐cyano‐2‐propyl‐dodecyl)trithiocarbonate as RAFT agent and azobis(isobutyronitrile) as initiator. Linear polyacrylonitrile (Mn = 133,000 g/mol, PDI = 1.34) was prepared within 7 h in 86% isolated yield. High‐yield copolymerization with methyl methacrylate (MMA) was performed and copolymerization parameters were determined according to Kelen and Tüdös at 90 °C in ethylene carbonate yielding rAN = 0.2 and rMMA = 0.42. The molecular weights, polydispersity indices (PDIs), and MMA content of the copolymer were adjusted in a way that precursor fibers could be prepared via wet spinning. These precursor fibers had round cross‐sections and a dense morphology, showing tenacities of 40–50 cN/tex and elastic moduli of 900–1000 cN/tex at a fineness of 1 dtex and an elongation of 13–17%. Precursor fibers were oxidatively stabilized and then carbonized at different temperatures. A maximum tensile strength of 2.5 GPa was reached at 1350 °C. Thermal analysis, infrared and Raman spectroscopy, wide‐angle X‐ray scattering, scanning electron microscopy, and tensile testing were used to characterize the resulting carbon fibers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1322–1333 相似文献