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71.
Okio Nomura 《International journal of quantum chemistry》1980,18(1):143-150
Global features of potential-energy curves are drawn using minimal basis SCF –CI method. Potential-energy surfaces are drawn at points of interest. The mechanism of the chemiluminescence is discussed along with the measurement of a rate constant exploiting the phenomena. 相似文献
72.
The α-decay properties of very short-lived N = 128 isotones, 216Ra, 217Ac and 218Th, were investigated by the pulsed-beam method. Alpha emitters of interest were produced in the bombardment of 208Pb or 209Bi with 65–96 MeV 12C or 14N ions and α-decays were measured between natural beam bursts of the cyclotron. The results obtained are Eα = 9.349±0.008 MeVand and and . The experimental reduced α-widths of N = 128 isotones from 212Po to 218Th are shown to agree well with the simple shell model calculation. 相似文献
73.
74.
Inoue Y Nomura Y Nakaoka T Watanabe M Kiryu S Okubo T Ohtomo K 《Magnetic resonance imaging》2005,23(5):641-645
The aim of this study was to investigate the effect of temporal resolution on the estimation of left ventricular (LV) function by cardiac magnetic resonance (MR) imaging using a steady-state free precession (SSFP) sequence. Left ventricular function was assessed by cine MR imaging using a segmented SSFP sequence in 10 healthy volunteers. Views per segment (VPS) were set at 8 and 20, resulting in high and low true temporal resolution, respectively. Irrespective of VPS, images were reconstructed at 40 cardiac phases, providing high apparent temporal resolution. Data were analyzed using 40, 20 and 10 phases to simulate different apparent temporal resolutions. Increasing the cardiac phases used for analysis slightly decreased mean end-systolic volume (ESV) and slightly increased mean ejection fraction (EF). No substantial difference in estimates of end-diastolic volume (EDV) was found between VPSs of 8 and 20. Imaging with a VPS of 20 yielded a larger ESV and smaller EF than imaging with a VPS of 8 when 40 phases were used. In conclusion, low true temporal resolution causes overestimation of ESV and underestimation of EF. Improvement of apparent temporal resolution mildly reduces but does not eliminate the errors caused by low true temporal resolution. 相似文献
75.
Taneda A 《Computational Biology and Chemistry》2005,29(2):324-119
In order to predict non-coding RNA genes and functions on the basis of genome sequences, accurate secondary structure prediction is useful. Although single-sequence folding programs such as mfold have been successful, it is of great importance to develop a novel approach for further improvement of the prediction performance. In the present paper, a secondary structure prediction method based on genetic algorithm, Cofolga, is proposed. The program developed performs folding and alignment of two homologous RNAs simultaneously. Cofolga was tested with a dataset composed of 13 tRNAs, seven 5S rRNAs, five RNase P RNAs, and five SRP RNAs; as a result, it turned out that the average prediction accuracies for the tRNAs, 5S rRNAs, RNase P RNAs, and SRP RNAs obtained by Cofolga with an optimal weight factor and default parameters were 83.6, 81.8, 73.5, and 67.7%, respectively. These results were superior to those obtained by a single-sequence folding based on free-energy minimization in which corresponding average prediction accuracies were 52.4, 47.4, 57.7, and 52.3%, respectively. Cofolga has a post-processing in which a single-sequence folding is performed after fixation of a predicted common structure; this post-processing enables Cofolga to predict a structure that is present in one of two RNAs alone. The executable files of Cofolga (for Windows/Unix/Mac) can be obtained by an e-mail request. 相似文献
76.
77.
A spin model is a square matrix that encodes the basic data for a statistical mechanical construction of link invariants due to V.F.R. Jones. Every spin model W is contained in a canonical Bose-Mesner algebra
(W). In this paper we study the distance-regular graphs whose Bose-Mesner algebra
satisfies W
(W). Suppose W has at least three distinct entries. We show that is 1-homogeneous and that the first and the last subconstituents of are strongly regular and distance-regular, respectively. 相似文献
78.
We propose an optical method for the investigation of the quantum dot edge channels by utilizing circularly polarized photoluminescence in the integer-quantum-Hall-effect regime. One of the advantages of our method is that the degree of the spin-polarization of the electrons in the inner- and outer-compressible liquids can be probed separately. The observed polarized photoluminescence spectra can be explained by the calculated electron spin-dependent optical transition probabilities based on the local-spin density approximation. 相似文献
79.
Photoelectrochemical decomposition of water on nanocrystalline BiVO4 film electrodes under visible light 总被引:1,自引:0,他引:1
Sayama K Nomura A Zou Z Abe R Abe Y Arakawa H 《Chemical communications (Cambridge, England)》2003,(23):2908-2909
The nanocrystalline BiVO4 film electrode on conducting glass showed an excellent efficiency (IPCE = 29% at 420 nm) for the decomposition of water under visible light. 相似文献
80.