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161.
Naoshi Baba Yoichirou Hanaoka Satoru Ueno Reizaburou Kitai Noriaki Miura Yuuki Noto Shuusuke Kato Susumu Kuwamura 《Optical Review》2007,14(3):159-160
This paper reports the performance of our modified adaptive optics system for solar observations. This system operates at
a frame rate of about 400 Hz and has the closed-loop cutoff frequency at 105 Hz. The results of the laboratory experiments
show that this system compensates for a temporal wavefront-variation of less than 99 Hz and improves the Strehl ratio by a
factor of five. 相似文献
162.
Hideyuki Kawahara Yoshihiro Ueno Nanae Abe Shiho Kishino Kazuhiro Ema Masahiro Rikukawa Yuko Tabuchi Naoya Ogata 《Optical Review》1997,4(1):188-190
We measured the third-order optical nonlinearity of regioregular head-to-tail coupled poly (3-hexylthiophene) (HT-PHT) and regiorandom poly (3-hexylthiophene) (R-PHT) around exciton resonance using degenerate four wave mixing. The observed value of ∣χ(3)∣ at the exciton resonance peak of HT-PHT is in the order of 10-9 esu which is approximately three-fold larger than that of R-PHT. We observed for the first time the enhancement in optical nonlinearity that occurs through the control of regularity of the polymeric structure. Response time of the nonlinearity was also measured using the transient grating method. The decay time of the transient grating in R-PHT and HT-PHT was less than 2 ps. 相似文献
163.
164.
Toshiyuki Katsura Yuji Shimizu Kenji Ueno 《Communications in Mathematical Physics》1989,121(4):603-627
New formulation of bosonization is given so that it is defined over the ring Z of integers. The charge zero sector of the new boson Fock space is the completion of the coordinate ring of the universal Witt scheme. By using new bosonization, conformal field theory of free fermions over Z is given.Dedicated to Professor M. Sato on his sixtieth birthdayPartially supported by Max-Planck-Institut für MathematikPartially supported by Max-Planck-Institut für Mathematik 相似文献
165.
Galactic cosmic-ray anisotropy and its modulation in the heliomagnetosphere, inferred from air shower observation at Mt. Norikura 总被引:1,自引:0,他引:1
K. Nagashima K. Fujimoto S. Sakakibara Z. Fujii H. Ueno I. Morishita K. Murakami 《Il Nuovo Cimento C》1989,12(6):695-749
Summary Extensive air showers (EAS) with median primary energy (E
m) of (1013÷1015) eV have been observed since 1970 at Mt. Norikura (2770 m above sea level; geographic latitude 36.1°N, longitude 137.6°E)
in order to study a cosmic-ray sidereal daily variation of galactic origin. We report here a summary of the observed results.
EAS shows a significant sidereal diurnal variation with an amplitude (0.060±0.003)% and a phase (0.8±0.3) h sidereal local
time forE
m≈1.5·1013eV. Sidereal semi- and tridiurnal variations also are statistically significant. These variations are proved to be of galactic
origin by a method which uses the difference of two directional (eastward and westward) air shower observations. It is found
that these variations are subject, as predicted by Nagashimaet al., to the annual variation due to the heliomagnetospheric modulation of the galactic anisotropy, which dominates in the rigidity
region ≈1012V, and further that the annual variation changes its phase due to the polarity reversal of the polar magnetic field of the
Sun, which occurs at the period of the maximum solar activity. This indicates that the anisotropy is produced by the charged
cosmic rays, contrary to the expectation from the γ-ray origin hypothesis suggested by Alexeenko and Navara. With the increase
ofE
m, the anisotropy seems to be reduced as we have not been able to detect any significant sidereal variation in EAS withE
m≈2·1014eV. This seems contradictory to the conventional conclusion that the energy spectrum of the anisotropy is flat or slightly
increases with energy.
Riassunto Sono stati osservati sciami cosmici estensivi (EAS) con energia primaria mediana (E m) di (1013⋎1015) eV dal 1970 a Mt. Norikura (2770m, latitudine geografica 36.1° N, longitudine 137.6° E) per studiare una variazione gionarliera siderale dei raggi cosmici di origine galattica. Si riporta una sintesi dei risultati osservati. EAS mostra una significativa variazione siderale diurna con ampiezza (0.060±0.03)% e fase (0.8±0.3)h in tempo locale siderale perE m∼1.5·1013eV. Le variazioni siderali semi e tri-diurne sono risultate anch'esse statisticamente significative. Si prova che queste variazioni sono d'origine galattica con un metodo che utilizza la differenza tra due osservazioni di sciami cosmici direzionali (est e ovest). Si trova che queste variazioni sono soggette, come previsto da Nagashimaet al., alla variazione annuale dovuta alla modulazione eliomagnetica dell'anisotropia galattica, che domina nella regione di rigidità ∼1012V e inoltre che la variazione annuale cambia fase a causa dell'inversione di polarità del campo magnetico polare del Sole, chesi verifica nel periodo di massima attività solare. Ciò indica che l'anisotropia è prodotta da raggi cosmici carichi, contrariamente a quanto previsto dall'ipotesi sull'origine da raggi gamma, suggerita da Alexeenko e Navara. Con l'aumento diE m, l'anisotropia sembra ridursi in quanto non siamo riusciti a rilevare una variazione siderale significativa in EAS conE m∼2·1014 eV. Questo risultato sembra in contraddizione con la conclusione convenzionale che lo spettro di energia dell'anisotropia è piatto o cresce appena con l'energia.
Резюме Широкие атмосферные ливни со средней первичной энергией (E m), равной (1013⋎1015) зВ, наблюдались с 1970 года на г. Нарикура (2770 м над уровнем моря; географическая широта 36.1°N, долгота 137.6°E), с целяю исследовать суточное изменение сидерических космических лучей галактической природы. Предлагается обзор полученных результатов. Широкие атмосферные ливни обнаруживают значительное сидерическое суточное изменение с амплитудой (0.060±0.003)% и фазой 0.8±0.3 часа сидерического времени дляE m∼1.5·1013 эВ. Сидерические полу-и трех-суточные изменения являются также статистически заметными. Доказывается, что эти изменения имеют галактическое происхождение. Этот результат получен с помощью метода, который использует разности при наблюдениях атмосферных ливней в двух направлениях (в восточном и западном направлениях). Получено, что эти вариации подчиняются, как было предсказано Нагашима и др., годовому изменению, обусловленному гелиомагнитосферной модуляцией галактической анизотропии, которая доминирует в области жесткости ∼1012 D, и кроме того, годовая вариация изменяет фазу, в связи с реверсированием полярности магнитного поля Солнца, котороепроисходит в период максимума солнечной активности. Этот реультат показывает, что возникает анизотропия, вызванная заряженными космическими лучами, в противоположность рредсказанию Алексеенко и Навара, связанному с гипотезой происхождения γ-лучей. При увеличенииE m анизотропия, повидимому, уменьшается, так как мы не смогли зарегистрировать какого-либо существенного сидерического изменения в пироких атмосферных ливнях в случаеE m∼2·1014эВ. Это противоречит общепринятому заключению, что энергетический спектр анизотропии является пологим или слегка увеличивается с энергией.相似文献
166.
Y. Yamada A. Kaji M. Itoh N. Kiriyama K. Komura K. Ueno 《Journal of Radioanalytical and Nuclear Chemistry》1989,135(5):381-388
The daily variation of14C concentrations of liberated CO2 in the free fermentation process of Japanese SAKE brewing was studied. Each of the concentrations measured in the initial and final stages of the fermentation process correlated with levels of koji rice and steamed rice used for SAKE production, which had been obtained from different areas. This shows that analysis of fermenting CO2 of SAKE could be used to estimate the14C level in a local environment. 相似文献
167.
K. Asahi H. Okuno H. Ueno H. Sato J. Kura T. Kubo T. Nakamura N. Inabe A. Yoshida Y. Ohkubo M. Adachi T. Ichihara M. Ishihara T. Shimoda H. Miyatake N. Takahashi D. Beaumel D. J. Morrissey W. -D. Schmidt-Ott 《Hyperfine Interactions》1992,75(1-4):101-108
Ejectile nuclei in the fragmentation of intermediate-energy heavy-ion projectiles were found to be largely spin polarized.
The observed polarization as a function of the outgoing momentum was nicely explained by a simple kinematical argument based
on the participant-spectator model of projectile fragmentation. The measurements extended to cover several different targets,
incident energies, exit channels, and emission angles revealed that substantial polarization shows up widely in projectile
fragmentation reactions. Furthermore, this polarization exhibits an interesting behavior which may be interpreted as a manifestation
of a gradual change in the deflection angle from positive to negative values as the energy increases and/or the target-Z decreases. The present polarization results also suggests various applications of spin polarized radioactive beams. As the
first example of such an application, we present a recent result on theg-factor measurements on neutron-rich nuclei. 相似文献
168.
Polystyrol microchannel-microheater chips were fabricated on the basis of imprinting and photolithography techniques. The solution (i.e., methanol) temperature in the vicinity of the microheater (width = 100 or 200 microm and length = 100 microm) integrated in the channel (width = 100 microm and depth = 20 microm) was evaluated on the basis of the temperature-dependent fluorescence lifetime of Rhodamine B as a function of a flow rate and the voltage applied to the heater. The study demonstrated that the fabricated chip acted certainly as a microheater. The chip was then applied to the thermal reaction between benzaldehyde and malononitrile in methanol. Under optimum conditions, benzilidenemalononitrile as the product of the reaction was obtained in a 96% yield with the reaction time of 84 s. 相似文献
169.
The effect of constraints on the initial steps of the incorporation of nitrogen on silicon has been assessed by calculations with the [Si9H12 + N] model cluster using density functional theory with the hybrid functional B3LYP, and two basis sets that differ significantly in size. The relative stability of the various stationary points is dependent on the type of constraints imposed on the cluster. Constrained calculations have predicted the structure with the nitrogen symmetrically bonded to the dimer silicons as the global minimum, however, if no constraint is imposed and the whole cluster is optimized, as done in this work, a structure with the nitrogen inserted between the dimer and the first layer and bonded to three silicon atoms is predicted to be the most stable one by about 17 kcal/mol by either the doublet or quartet route. The whole process is very exothermic and reaction barriers in the intermediate steps are easily overcome. Calculations with the smaller basis do not essentially change the major conclusion about the relative stability of the various stationary points. The most stable structure and frequency calculations are consistent with a planar NSi3 moiety and its asymmetrical stretching frequency. 相似文献
170.
Akihiko Ueno Fumio Moriwaki Tetsuo Osa Fumio Hamada Koichi Murai 《Tetrahedron letters》1985,26(7):899-902
Circular dichroism measurements show that β-cyclodextrin with an amino moiety has a strong binding ability for ferrocenecarboxylic acid in dimethyl sulfoxide via an acid-base interaction. 相似文献