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141.
王恩耀 《核聚变与等离子体物理》1999,19(2):116-119
报道了HL-1M装置1998年度物理实验的进展情况。主要包括等离子体密度极限,中性束注入加热,离子回旋共振加热,低温杂波离子加热,多发弹丸注入,超声分子束注入等实验的情况。 相似文献
142.
RE Tribble A Azhari HL Clark CA Gagliardi Y-W Lui AM Mukhamedzhanov A Sattaroy X Tang L Trache V Burjan J Cejpek V Kroha S Piskor J Vincour F Carstoiu 《Pramana》1999,53(3):585-594
S-factors for direct capture reactions can be found at astrophysical energies from asymptotic normalization coefficients which
provide the normalization of the tail of the overlap function. For example the overlap for 8B → 7Be+p defines the S-factor for 7Be (p, γ)8B. Peripheral transfer reactions offer a technique to determine these asymptotic normalization coefficients. As a test of
the technique, the 16O(3He, d)17F reaction has been used to determine asymptotic normalization coefficients for transitions to the ground and first excited
states of 17F. The S-factors for 16O(p, γ)17F calculated from these 17F → 16O+p asymptotic normalization coefficients are found to be in very good agreement with recent measurements. Following the same
technique, the 10B(7Be, 8B)9Be and 14N(7Be, 8B)13C reactions have been used to measure the asymptotic normalization coefficient for 7Be(p, γ)8B. This result provides an indirect determination of S
17(0). 相似文献
143.
R Korporaal A Ridder P Kloprogge R Dekker 《The Journal of the Operational Research Society》2000,51(11):1228-1237
In this paper we describe a decision support system developed to help in assessing the need for various types of prison cells. In particular we predict the probability that a criminal has to be sent home because of a shortage of cells. The problem is modelled through a queuing network with blocking after service. The main objective of our study is to describe our analytical method and an approximate algorithm to solve this network. Through simulation studies we evaluate our method. Both the analytic and the simulation tool are elements of the decision support system. 相似文献
144.
145.
Anthony Dekker Hebert Pérez-Rosés Guillermo Pineda-Villavicencio Paul Watters 《Journal of Mathematical Modelling and Algorithms》2012,11(3):249-268
We introduce the problem of finding the largest subgraph of a given weighted undirected graph (host graph), subject to constraints on the maximum degree and the diameter. We discuss some applications in security, network design and parallel processing, and in connection with the latter we derive some bounds for the order of the largest subgraph in host graphs of practical interest: the mesh and the hypercube. We also present a heuristic strategy to solve the problem, and we prove an approximation ratio for the algorithm. Finally, we provide some experimental results with a variety of host networks, which show that the algorithm performs better in practice than the prediction provided by our theoretical approximation ratio. 相似文献
146.
Douglas J. Little Martin Ams Simon Gross Peter Dekker Christopher T. Miese Alex Fuerbach Michael J. Withford 《Journal of Raman spectroscopy : JRS》2011,42(4):715-718
A general picture of refractive index change mechanisms in glass modified by a femtosecond laser has proven elusive. In this paper, Raman microscopy was used in conjunction with refractive near‐field profilometry to analyse the structure of borosilicate glass (Schott BK7) modified by a femtosecond laser and determine the mechanism of the observed refractive index change. For a pulse repetition rate of 1 kHz, it was determined that the refractive index change was due to an elevated population of non‐bridging oxygen atoms, resulting in more ionic bonds forming within the glass network and increasing the molar refractivity of the glass. For a pulse repetition rate of 5.1 MHz, the dominant mechanism of refractive index change was densification and rarefaction of the glass network. Different refractive index change mechanisms were attributed to different thermal conditions imparted to the glass under different pulse repetition rates. Implications for device fabrication are also discussed. These findings constitute an important step toward a complete overview of femtosecond‐laser‐induced refractive index change in glass. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
147.
Virendra Kumar Yuhua Gu Satrajit Basu Anders Berglund Steven A. Eschrich Matthew B. Schabath Kenneth Forster Hugo J.W.L. Aerts Andre Dekker David Fenstermacher Dmitry B. Goldgof Lawrence O. Hall Philippe Lambin Yoganand Balagurunathan Robert A. Gatenby Robert J. Gillies 《Magnetic resonance imaging》2012
148.
149.
Romero E van Stokkum IH Dekker JP van Grondelle R 《Physical chemistry chemical physics : PCCP》2011,13(13):5573-5575
We show a correlation between the electronic excitation of the peripheral chlorophylls (Chls(Z)) of the photosystem II reaction center and a shift of the S(2) absorption bands of β-carotene, and suggest that the carotenoids may enhance the excitation energy transfer rate from these chlorophylls to the central cofactors. 相似文献
150.
中国环流器新一号装置总体联调 总被引:2,自引:1,他引:1
谈满秋 《核聚变与等离子体物理》1997,17(2):1-8
本文介绍中国环流器新一号装置工程总体联合调试的内容和主要结果。该装置总体联调是非常成功的,获得了重复性很好,环电流平顶宽的稳定平稳的放电波形,这对物理实验的开展非常有利。 相似文献