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151.
152.
Daniele Cauzzi Roberto Giordano Enrico Sappa Antonio Tiripicchio Marisa Tiripicchio Camellini 《Journal of Cluster Science》1993,4(3):279-296
The title complex (complex1) was the first alkyne-substituted triruthenium dihydrido cluster to be reported and was characterized by spectroscopy as a triangular cluster with the alkyne parallel to a Ru-Ru edge. Recently, we have found that1 is a key intermediate in the homogeneous hydrogenation of diphenylacetylene catalyzed by tetrahedral Ru4 and FeRu3 clusters. Since the discovery of1, a great number of complexes with alkynes parallel to a cluster edge have been reported; at present this is the more common bonding mode for alkynes on trinuclear clusters. The structural features of1 allow a comparison with those of other ruthenium-containing derivatives and help to draw suggestions of the role of1 in hydrogenation catalysis. 相似文献
153.
154.
Vasily L. Morgunov 《Pramana》2007,69(6):1097-1100
A new calorimeter energy calibration method was developed for the proposed ILC detectors. The method uses the center-of-mass
energy of the accelerator as the reference. It has been shown that using the energy conservation law it is possible to make
ECAL and HCAL cross calibration to reach a good energy resolution for the simple calorimeter energy sum.
相似文献
155.
156.
Yong Nam Choi Shin Ae Kim Sung Kyu Kim Sung Baek Kim Chang-Hee Lee Pavel Mikula 《Pramana》2004,63(1):175-181
In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction
experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However,
a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution
property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction
experiment. From the data of the FWHM and the Δd/d measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that
the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved. 相似文献
157.
Forecasting electricity prices in presentday competitive electricity markets is a must for both producers and consumers because both need price estimates to develop their respective market bidding strategies. This paper proposes a transfer function model to predict electricity prices based on both past electricity prices and demands, and discuss the rationale to build it. The importance of electricity demand information is assessed. Appropriate metrics to appraise prediction quality are identified and used. Realistic and extensive simulations based on data from the PJM Interconnection for year 2003 are conducted. The proposed model is compared with naïve and other techniques. 相似文献
158.
Alessandro Cecchi Giuditta Bartalucci Cinzia Chiappe Roberto Bianchini 《国际化学动力学杂志》2007,39(4):197-203
The kinetics of the electrophilic bromination of three allylic ethers in a nonprotic solvent, 1,2‐dichloroethane, has been investigated. Two of them followed a prevalent second‐order pathway, while the third one exhibited a classical, clean third order. The second‐order pathway in the first two olefins is attributed to electrophilic assistance of the ethereal oxygen to the attacking bromine molecule. In the molecular bromination of 2,4‐cis‐dimethyl‐8‐oxabicyclo[3.2.1]‐6‐octen‐3‐cis‐ol, opposite temperature dependences were found for the two different kinetic pathways. An exoergonic process for the second‐order reaction was explained by the lesser stability of the bromiranium–bromide ionic intermediate, compared to the bromiranium–tribromide in the third‐order profile. © 2007 Wiley Periodicals, Inc. 39: 197–203, 2007 相似文献
159.
In this paper we generalize to coisotropic actions of compact Lie groups a theorem of Guillemin on deformations of Hamiltonian
structures on compact symplectic manifolds. We show how one can reconstruct from the moment polytope the symplectic form on
the manifold.
Received: 21 March 2006 相似文献
160.
David Stanovský 《Czechoslovak Mathematical Journal》2007,57(1):191-200
We investigate the variety of residuated lattices with a commutative and idempotent monoid reduct. 相似文献