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971.
Eizi Hirota Yasuki Endo Shuji Saito Kazuhiko Yoshida Ichiro Yamaguchi Katsunosuke Machida 《Journal of Molecular Spectroscopy》1981,89(1):223-231
The pure rotational spectra of three deuterated ethylenes, CH2CD2, CH2CHD, and cis-CHDCHD, were observed by microwave spectroscopy, and the rotational and centrifugal distortion constants were determined precisely. The dipole moment of CH2CD2 was calculated from the Stark effects to be 0.0091 ± 0.0004 D. From the observed rotational constants the average structure was calculated to be , , θz(CCH) = 121.28 ± 0.10°, and , where the errors include one standard deviation in the fitting and errors due to an uncertainty (±0.03°) in θz(CCH) - θz(CCD). 相似文献
972.
We formulate a path integral of chiral gauge theories by means of the canonical quantization of fermions in time-dependent background gauge fields. The expression of the path integral is composed of two parts. One is due to the nontrivial holonomy of the fermionic Fock vacua and the other is the conventional form which is used in the perturbation theory. The nontrivial holonomy part is expected to be a nonlocal counter term. We show a possibility of the perturbative calculation 相似文献
973.
K. Nagashima S. Sakakibara K. Fujimoto R. Tatsuoka I. Morishita 《Il Nuovo Cimento C》1990,13(3):551-587
Summary Forbush decrease (FD) is generally interpreted as a result of diffusion-convection of cosmic rays in a disturbed interplanetary
magnetic field associated with the magnetohydrodynamic shock wave caused by solar flare. In this paper, we point out that
a large number of FDs contain an isolated region or regions with pit-type time profile, in which cosmic rays are not in a
diffusion-convection state but in a trapped state in undisturbed, uniform and strong magnetic field perpendicular to the solar
wind. The trapped state is also characterized with a large ratio of the magnetic to ion thermal energy. The median duration
time of the state is about 8 hours. About half of these states are associated with the northward (or southward) magnetic field,
while the other half with the eastward (or westward) magnetic field. Flares responsible for the former state seem to be concentrated
in an eastward region from about 30°W on the solar disk, while those for the latter state seem rather symmetric with respect
to the centre of the solar disk. It is suggested that the trapped state is produced inside a magnetic tube of force which
is not of a small scale such as that of the magnetic bubble pointed out by Klein and Burlaga, but of a large scale, having
a horseshoe structure with its ends supposed to be connected to somewhere in an inner region near the Sun and with its cross-section
supposed to be of a thin filament with radial and transverse dimensions of ≈0.1 a.u. and ≈1.1 a.u. at the Earth’s orbit. This
belt-like tube of force is supposed to be produced on the solar surface or near the Sun and to be carried out by solar wind
in a frozen state, trapping in itself low-density cosmic rays near the Sun. In addition to the pits, we point out also the
existence of some peaks which are observed not only in the trapped region but also in a region of extremely disturbed magnetic
field neighbouring in between two trapped regions. It is suggested that cosmic rays in the region of the latter type are supposed
to be guided freely (or easily) from outer space through a path with similarly disturbed magnetic state, and therefore, they
could maintain their density in the region always higher than in the neighbouring regions. Two kinds of cosmic-ray-guiding
mechanism in the above can be regarded as being at opposite poles. 相似文献
974.
The dianion of N-phenyl-2-(phenylsulfonylmethyl)propenamide was found to be an efficient reagent for the synthesis of (E)-α,β-unsaturated amides and 5,6-dihydro-2H-pyrans. 相似文献
975.
Masataka Okuyama Kazuhiko Yamamoto Tomomi Yanagida Tatsuzo Hirose 《Colloid and polymer science》1966,208(1):13-15
Summary The polymerizate is a porous, white cylinder of polyoxymethylene, whose direction of crystal axis is unique. The dynamic viscoelasticity was measured by the vibrating-reed-method at –180° +10 °C. The existence of the -dispersion is doubtful in this sample. Therefore we can conclude that (i) the amorphous part is negligibly small both on the surface and inside of this sample, and (ii) the vibration of molecular chains is prohibited even on the surface of a single crystal.
This work was presented at the 43rd Annual Meeting of Virginia Academy of Science, Richmond, Virginia, May 7, 1965. 相似文献
Zusammenfassung Das Polymerisat ist ein poröser, weißer Zylinder von Polyoxymethylen mit einheitlich ausgerichteter Kristallachse. Die dynamische Viscoelastizität wurde zwischen –180° und +10 °C nach der Methode des vibrierenden Stäbchens bestimmt. Die Existenz des-Dispersionsgebiets ist bei dieser Probe zweifelhaft. Wir können daher folgern, daß 1. der amorphe Anteil vernachlässigbar klein — sowohl an der Oberfläche wie im Innern — ist und daß 2. die Schwingung der Molekülketten sogar auch in der Grenzfläche eines Einkristalls behindert, unterbunden ist.
This work was presented at the 43rd Annual Meeting of Virginia Academy of Science, Richmond, Virginia, May 7, 1965. 相似文献
976.
Fluoride complexation of element 104, rutherfordium 总被引:1,自引:0,他引:1
Haba H Tsukada K Asai M Toyoshima A Akiyama K Nishinaka I Hirata M Yaita T Ichikawa S Nagame Y Yasuda K Miyamoto Y Kaneko T Goto S Ono S Hirai T Kudo H Shigekawa M Shinohara A Oura Y Nakahara H Sueki K Kikunaga H Kinoshita N Tsuruga N Yokoyama A Sakama M Enomoto S Schädel M Brüchle W Kratz JV 《Journal of the American Chemical Society》2004,126(16):5219-5224
Fluoride complexation of element 104, rutherfordium (Rf), produced in the 248Cm(18O,5n)261Rf reaction has been studied by anion-exchange chromatography on an atom-at-a-time scale. The anion-exchange chromatographic behavior of Rf was investigated in 1.9-13.9 M hydrofluoric acid together with those of the group-4 elements Zr and Hf produced in the 18O-induced reactions on Ge and Gd targets, respectively. It was found that the adsorption behavior of Rf on anion-exchange resin is quite different from those of Zr and Hf, suggesting the influence of relativistic effects on the fluoride complexation of Rf. 相似文献
977.
This paper aims at developing an integrated design method of the active/passive hybrid type of piezoelectric damping system for reducing the dynamic response of the flexible structures due to external dynamic loads. The design method is based on the numerical optimization technique whose objective function is a control effort of the active damping. A vibration suppression performance, which is evaluated by the maximum value of the gain of the frequency response function of the structure, is constrained. In order to demonstrate the structural damping capability of the hybrid type of piezoelectric damping system designed by proposed method, numerical simulation and laboratory experiment will be done using a three-story flexible structure model equipped with 12 surface bonded PZT tiles pairs. Both numerical and experimental results indicate that the optimally designed hybrid piezoelectric damping system can be successfully achieving excellent performance as compared to a conventional purely active piezoelectric damping system. 相似文献
978.
We propose that the spin-triplet pairing mechanism due to disconnected Fermi surfaces proposed in our previous study [Phys. Rev. B 63, 174507 (2001)]] may be at work in a recently discovered superconductor NaxCoO2.yH2O. We introduce a single band effective model that takes into account the pocketlike Fermi surfaces along with the van Hove singularity near the K point found in the band calculation results. Applying the fluctuation exchange method and solving the linearized Eliashberg equation, the most dominant pairing is found to have spin-triplet f-wave symmetry, where the nodes of the gap function do not intersect the pocket Fermi surfaces. The presence of finite Tc is suggested in sharp contrast to cases when the gap nodes intersect the Fermi surface. 相似文献
979.
The effective formation of 1-azabicyclo[1.1.0]butane (2) by treatment of 2,3-dibromopropylamine hydrobromide (1) with n-BuLi could be understood considering a rational reaction pathway via both transition states 10 and 19 based on the intramolecular Br...Li(+) coordination. A similar cyclization pathway starting from N-benzyl-3-bromopropylamine hydrochloride (17) to afford N-benzylazetidine (18) could also be postulated on the basis of a transition state 20 involving the intramolecular Br...Li(+) coordination. 相似文献
980.
Evaluation of homology modeling of the severe acute respiratory syndrome (SARS) coronavirus main protease for structure based drug design 总被引:1,自引:0,他引:1
Takeda-Shitaka M Nojima H Takaya D Kanou K Iwadate M Umeyama H 《Chemical & pharmaceutical bulletin》2004,52(5):643-645
To accelerate the development of drugs against severe acute respiratory syndrome (SARS), we constructed a homology model of the SARS coronavirus main protease using our modeling software, FAMS Ligand&Complex, and released it before the X-ray structure was solved. The X-ray structure showed our model as accurately predicted and useful for structure based drug design. 相似文献