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991.
992.
Sergio Caracciolo Maria Serena Causo Giovanni Ferraro Mauro Papinutto Andrea Pelissetto 《Journal of statistical physics》2000,100(5-6):1111-1145
We introduce several bilocal algorithms for lattice self-avoiding walks. We discuss their ergodicity in different confined geometries, for instance in strips and in slabs. A short discussion of the dynamical properties in the absence of interactions is given. 相似文献
993.
994.
B.A. Sava Adriana Diaconu Lucica Boroica Daniela Ursu T. Visan M. Elisa Alina Balu 《Journal of Non》2009,355(37-42):2020-2022
The paper studies the materials from ZnO–TiO2–B2O3 ternary system, obtained by sol–gel method [1] and [2], starting from organic and inorganic precursors. The obtained samples are investigated by FTIR and Raman spectroscopy, which provide structural information, at molecular level. FTIR absorption maxima are identified and discussed according to literature data. Raman spectra are acquired by a Raman Jasco NRS-3100 spectrometer, at 532 nm wavelength and put in evidence characteristic vibration modes for all three oxide components. ESR spectra were plotted with the aid of a JES-FA 100-JEOL Japan spectrometer and titanium surrounding is investigated. 相似文献
995.
The paper describes a generalized optimization method for night vision devices (NVDs) design taking into account stochastic external surveillance conditions – ambient light illumination, atmosphere transmittance, contrast between target and background and target type. The main idea of the presented method is optimizing of the NVD design process by optimal choice of the optoelectronic channel modules – objective, image intensifier tube, ocular and electrical battery power supply while considering the influence of the external surveillance conditions uncertainty. For that goal a stochastic nonlinear mixed-integer multicriteria optimization problem is formulated and solved. The problem solution gives the optimal modules combination and some preliminary estimation about the operational characteristics of the designed NVD – working range (consistent with the uncertainty of the external surveillance conditions), weight, price and electrical batteries power supply operational duration. An illustrative numerical example based on the optimal choice from sets of objectives, image intensifier tubes, oculars and electrical batteries types is solved. The described method increases the effectiveness of the NVD design. 相似文献
996.
Daniela Favaretto Bruno Viscolani 《4OR: A Quarterly Journal of Operations Research》2010,8(2):141-153
We bring some concepts from market segmentation, which is a fundamental topic of marketing theory and practice, into the statement
of an advertising and production problem for a seasonal product with Nerlove–Arrow’s linear goodwill dynamics. We consider
two kinds of situations. In the first one, the advertising process can reach selectively each segment. In the second one,
one advertising medium is available which has a known effectiveness spectrum for a non-trivial set of segments. In both cases
we solve, using the Pontryagin’s Maximum Principle conditions, the optimal control problems in which goodwill productivity
of advertising is concave and good production cost is convex. Two special cases are discussed in detail. 相似文献
997.
Recently, different mixture models have been proposed for multilevel data, generally requiring the local independence assumption. In this work, this assumption is relaxed by allowing each mixture component at the lower level of the hierarchical structure to be modeled according to a multivariate Gaussian distribution with a non-diagonal covariance matrix. For high-dimensional problems, this solution can lead to highly parameterized models. In this proposal, the trade-off between model parsimony and flexibility is governed by assuming a latent factor generative model. 相似文献
998.
Daniela Belli Dell’Amico Luca Labella Fabio Marchetti Simona Samaritani 《Journal of organometallic chemistry》2011,696(7):1349-1354
Convenient one-pot reduction-complexation reactions of hexachloroplatinato(IV) anions to (η4-alkadiene)dichloroplatinum(II) complexes (η4-alkadiene = COD, DAE, DCPD, NBD) under suitable phase-transfer catalysis conditions are reported. Reduction to zerovalent platinum alkene complexes has been obtained in the presence of an excess of alkene, potassium formate and 18-crown-6 as phase-transfer catalyst (alkene = COD, NB, dba). The crystal and molecular structure of [Pt1.03(dba)3]·CH2Cl2 has been studied by X-ray diffraction methods: it can be described as a solid solution of Pt(dba)3 and Pt2(dba)3, the mononuclear complex being largely prevailing. 相似文献
999.
Prof. Dr. Holger Braunschweig Prof. Ching‐Wen Chiu Alexander Damme Prof. Dr. Bernd Engels Dr. Daniela Gamon Christian Hörl Dr. Thomas Kupfer Dr. Ivo Krummenacher Dr. Krzysztof Radacki Christof Walter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(45):14292-14304
Herein, we report the synthesis of boroles that are linked by a conjugated phenylene spacer. The characterization of these compounds was completed by NMR and UV/Vis spectroscopy, as well as X‐ray crystal diffraction. Furthermore, the coordination behavior of these oligoboroles towards five electronically and sterically disparate pyridine derivatives was studied and revealed fundamental differences in the properties of the resulting adducts. The experimental results were supported by density functional theory (DFT) calculations that showed a charge‐transfer effect upon formation of the pyridine‐4‐carbonitrile adduct. By chemical reduction of a tris(borolyl)‐substituted benzene derivative, a hexaanion was isolated as a result of a two‐electron reduction of each borolyl moiety. The interaction of the borolyl units through the aryl spacer, and the possible increase of the Lewis acidity due to the conjugation of the borolyl moieties, were investigated by base transfer reactions. 相似文献
1000.
The chemistry of terminal transition metal borylene complexes is reviewed, with particular attention to recent developments concerning the reactivity of these species. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:238–238, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20247 相似文献