1,052 research outputs found
Some Modifications of the Free-Electron Model
The perimeter-free-electron model which is rather the crude approximation for the calculation of the π-electronic spectra of a conjugated system is modified at some points. How the linear addition of a conjugated chain or phenyl groups to benzene will cause the red-shifts of their spectra with the increase of the length of chain or the number of phenyl is discussed by connecting them with each other so as to make the total one-electron wave function well behaved. The effects of the nuclear substitution with a heteroatom in the benzene ring are studied in the case of pyridine. The red-shifts of center of gravity of the actual singlets of pyridine, compared with that of benzene, is explained by the insertion of a suitable potential well along the perimeter-loop. As a typical non-alternant hydrocarbon, we take azulene and its absorption spectrum, electron density and red- or blue-shifts of the longest wave length transition on alkylation are calculated. These modifications raise the degree of approximation of the free-electron model up to that of the simple LCAO molecular orbital treatment
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Regulation and Supervision
Why did Lehman Brothers have to go bankrupt? This question has often been asked since the bankruptcy of Lehman was recognized as having a hugely disruptive effect on the financial system and the economy around the world beyond expectations. For that question, a broad range of materials have provided various answers from each viewpoint. FCIC‘s report indicates that risky trading activities, enormous leverage, reliance on short-term funding, problems in its corporate governance including risk management as well as inadequate regulatory oversight can be significant causes of Lehman‘s collapse. However, why could such common weaknesses not be easily corrected or improved but be overlooked for a long time, and lead to such a huge calamity? A more in-depth investigation or a study from a different viewpoint may be required to grasp the essence of this problem and to find the right way and direction of regulatory reforms. In this essay, from the case studies of Bear Sterns, Lehman Brothers, and AIG, some of the essential weaknesses in their risk management and in the Federal Reserve‘s supervision especially over their liquidity risk are pointed out. Then, by comparing with the framework and conduct of the BOJ‘s monitoring of financial institutions‘ liquidity, the reasons why the Federal Reserve could not sufficiently exert its regulatory and supervisory power over those financial institutions‘ liquidity risk management will be examined. Finally, based on the analysis above, some assessment of Dodd-Frank regulatory reforms will be added
Mixed expansion formula for the rectangular Schur functions and the affine Lie algebra A_1^(1)
Formulas are obtained that express the Schur S-functions indexed by Young
diagrams of rectangular shape as linear combinations of "mixed" products of
Schur's S- and Q-functions. The proof is achieved by using representations of
the affine Lie algebra of type A_1^{(1)}. A realization of the basic
representation that is of ``D_2^{(2)}''-type plays the central role.Comment: 21page
An experimental study on influence of shear failure type partial wall on reinforced concrete frame
Partial walls separated from columns are generally treated as nonstructural elements because their behavior aren’t analyzed much. Partial walls jointed rigidly to RC frames raise horizontal load-carrying capacity, however they may give an influence on RC frames when they fall in brittle failure. Objective of this paper is to clarify the influence of partial walls falling in shear failure on RC frames through a static loading test and a shaking table test. The experiment shows that, after one of the partial walls fails, story drift rapidly increases. It shows progress of flexural deformation at one end of columns, and it may cause story collapse. The result is obtained from both loading tests
3-D Kinematics of Water Masers in the W51A Region
We report proper motion measurements of water masers in the massive-star
forming region W51A and the analyses of the 3-D kinematics of the masers in
three maser clusters of W51A (W51 North, Main, and South). In W~51 North, we
found a clear expanding flow that has an expansion velocity of ~70 km/s and
indicates deceleration. The originating point of the flow coincides within 0.1
as with a silicon-monoxide maser source near the HII region W~51d. In W51 Main,
no systematic motion was found in the whole velocity range (158 km/s =< V(lsr)
=< -58 km/s) although a stream motion was reported previously in a limited
range of the Doppler velocity (54 km/s =< V(lsr) =< 68 kms). Multiple driving
sources of outflows are thought to explain the kinematics of W51 Main. In W51
South, an expansion motion like a bipolar flow was marginally visible. Analyses
based on diagonalization of the variance-covariance matrix of maser velocity
vectors demonstrate that the maser kinematics in W51 North and Main are
significantly tri-axially asymmetric. We estimated a distance to W51 North to
be 6.1 +/- 1.3 kpc on the basis of the model fitting method adopting a radially
expanding flow.Comment: 20 pages, 8 figures, 8 tables, appear in the NRO report No. 564
(ftp://ftp.nro.nao.ac.jp/nroreport/PASJ-W51.pdf) and will appear in Publ.
Astron. Soc. Japan, Vol. 54, No. 5 (10/25 issue
パール判決書と戦後日本のナショナリズム
アジア新時代の南アジアにおける日本像 : インド・SAARC 諸国における日本研究の現状と必要性, ジャワハルラル・ネルー大学, 2009年11月3日-4
X-Ray Reflection Nebulae with Large Equivalent Widths of Neutral Iron Ka Line in the Sgr C Region
This paper reports on the first results of the Suzaku observation in the Sgr
C region. We detected four diffuse clumps with strong line emission at 6.4keV,
Ka from neutral or low-ionized Fe. One of them, M359.38-0.00, is newly
discovered with Suzaku. The X-ray spectra of the two bright clumps,
M359.43-0.07 and M359.47-0.15, after subtracting the Galactic center diffuse
X-ray emission (GCDX), exhibit strong Ka line from FeI with large equivalent
widths (EWs) of 2.0-2.2keV and clear Kb of FeI. The GCDX in the Sgr C region is
composed of the 6.4keV- and 6.7keV-associated components. These are
phenomenologically decomposed by taking relations between EWs of the 6.4keV and
6.7keV lines. Then the former EWs against the associated continuum in the
bright clump regions are estimated to be 2.4(+2.3_-0.7)keV. Since the two
different approaches give similar large EWs of 2keV, we strongly suggest that
the 6.4keV clumps in the Sgr C region are due to X-ray reflection/fluorescence
(the X-ray reflection nebulae).Comment: Accepted for publication in PAS
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