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71.
Kian-Tat Lim Sharon Brunett Mihail Iotov Richard B. McClurg Nagarajan Vaidehi Siddharth Dasgupta Stephen Taylor William A. Goddard 《Journal of computational chemistry》1997,18(4):501-521
We describe the implementation of the cell multipole method (CMM) in a complete molecular dynamics (MD) simulation program (MPSim) for massively parallel supercomputers. Tests are made of how the program scales with size (linearly) and with number of CPUs (nearly linearly) in applications involving up to 107 particles and up to 500 CPUs. Applications include estimating the surface tension of Ar and calculating the structure of rhinovirus 14 without requiring icosahedral symmetry. © 1997 by John Wiley & Sons, Inc. 相似文献
72.
Alexander G. Strikovsky Vadim V. Zharkov Mihail P. Letunovsky 《Macromolecular Symposia》1995,94(1):181-188
The equilibrium association of urethane groups in a series of 4, 4′ - diphenylmethane diisocyanate (MDI)/polypropylene oxide) (PPO) based poly(ether urethane) elastomers (PUE) was studied on the basis of IR-spectroscopy data. The concentration of associates containing 2,3 and 4 urethane groups is calculated, which permits immediate monitoring of changes in PUE mechanical properties using the model of a physically cross-linked polymer. 相似文献
73.
Lucian Gabriel Bahrin Alina Nicolescu Sergiu Shova Narcisa Laura Marangoci Lucian Mihail Birsa Laura Gabriela Sarbu 《Molecules (Basel, Switzerland)》2021,26(19)
Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey–Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network. 相似文献
74.
Kristian Piscicchia Johann Marton Sergio Bartalucci Massimiliano Bazzi Sergio Bertolucci Mario Bragadireanu Michael Cargnelli Alberto Clozza Raffaele Del Grande Luca De Paolis Carlo Fiorini Carlo Guaraldo Mihail Iliescu Matthias Laubenstein Marco Miliucci Edoardo Milotti Fabrizio Napolitano Andreas Pichler Alessandro Scordo Hexi Shi Diana Laura Sirghi Florin Sirghi Laura Sperandio Oton Vazquez Doce Johann Zmeskal Catalina Curceanu 《Entropy (Basel, Switzerland)》2020,22(11)
The VIP collaboration is performing high sensitivity tests of the Pauli Exclusion Principle for electrons in the extremely low cosmic background environment of the underground Gran Sasso National Laboratory INFN (Italy). In particular, the VIP-2 Open Systems experiment was conceived to put strong constraints on those Pauli Exclusion Principle violation models which respect the so-called Messiah–Greenberg superselection rule. The experimental technique consists of introducing a direct current in a copper conductor, and searching for the X-rays emission coming from a forbidden atomic transition from the L shell to the K shell of copper when the K shell is already occupied by two electrons. The analysis of the first three months of collected data (in 2018) is presented. The obtained result represents the best bound on the Pauli Exclusion Principle violation probability which fulfills the Messiah–Greenberg rule. 相似文献
75.
Dumitrescu Mihail Saarinen Mika Guina Mircea Komsa Hannu Pessa Markus 《Optical and Quantum Electronics》2003,35(6):589-613
Resonant cavity light emitting diodes (RC-LEDs) and vertical cavity surface emitting lasers (VCSELs) for the red wavelength range are presented in the paper. A wide variety of simulation tools were employed in the device design and optimization and the good agreement between simulations and measurements enabled effective device development. Our red wavelength range RC-LEDs were mainly intended for short-haul communication systems based on polymethyl methacrylate plastic optical fiber and were optimized accordingly. They are achieving, under different structure and working regime variants, high output power (15 mW), high external efficiency (9.5%), record small-signal modulation bandwidth (f
-3dB
up to 350 MHz), error-free back-to-back transmission rates beyond 622 Mbits/s, adjustable far-field pattern and good POF coupling efficiency with reasonably wide tolerances and without using auxiliary optics. In view of the possible use of graded-index POFs, free-space transmission and other high bandwidth or high spectral purity applications, VCSELs in the red wavelength range were also realized. They have achieved sub-milliamp room-temperature (RT) continuous-wave (CW) lasing for an 8 m diameter emission window and exhibited an external quantum efficiency of 6.65% for 10 m devices in RT CW operation. The VCSEL structures were far from optimal – not even incorporating all the RC-LED structure refinements – and significant improvement in performance characteristics are predicted for the optimized layer structure. 相似文献
76.
It is shown that the correctly written “1/k4” propagator in four space-time dimensions leads to a consistent pertubative expansion of a superrenormalizable (asymptotically free) abelian gauge model. Confinement is found in any order of perturbation theory. A discussion of the physical space is sketched and the violation of asymptotic completeness is pointed out. 相似文献
77.
Adrian–Mihail Stoica 《PAMM》2007,7(1):1061101-1061102
The aim of this paper is to present a design methodology for an observer–based fault detection filter. This approach allows to compute a filter gain such that both fault detection and disturbance attenuation requirements are accomplished. The developments are based on H∞ optimization in the discrete–time framework. The existence conditions for the observer–based detection filter are expressed in terms of feasibility of a system of matrix inequalities. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
78.
79.
Arcady Zhukov Mihail Ipatov Ahmed Talaat Margarita Churyukanova Sergei Kaloshkin Valentina Zhukova 《Applied Physics A: Materials Science & Processing》2014,115(2):547-553
We present the results on Giant magneto-impedance effect (GMI) in amorphous and nanocrystalline microwires at frequencies until 4 GHz, paying special attention to tailoring the frequency and magnetic field dependence of the GMI effect. Correlation between magnetoelastic anisotropy and magnetic field dependences of diagonal and off-diagonal impedance components are observed. 相似文献
80.
Dr. Yves‐Marie Legrand Dan Dumitrescu Dr. Arnaud Gilles Eddy Petit Dr. Arie van der Lee Dr. Mihail Barboiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(15):4938-4941
Following earlier reports on the photochemical synthesis of 1,3‐dimethylcyclobutadiene 8 , 10 in a protective host matrix, theoretical calculations for the formation of that adduct have been recently performed by Rzepa. 13 The author formulated criticisms based mainly on density functional theory calculations of 1H NMR spectra. According to Rzepa the calculated spectra do not correspond with our measured spectra, which leads him to the conclusion that our interpretation is wrong, and that mainly cyclobutadiene has not been stabilized or even synthesized; we believe, however, that the initial model that Rzepa used for his calculations does not correspond to chemical reality or is at the very least a crude simplification of it, which implies that his calculations cannot match, in every point, our experimental spectra. Rzepa′s simplified models might be ‘reasonable’ from the theoretical point of view; however, in the case of assessment in the solid state, the theoretical setup does not force the system to preserve the confined stabilizing space defined by the crystalline matrix for encapsulated hosts in the solid state. Inversely, in the case of solution modeling, the theoretical setup is too rigid to properly assess the complex equilibria occurring in solution and to accurately determine the NMR spectra of exchanging species in solution. The inconsistency between our experimental results and the results of the theoretical models proposed by Rzepa is such that his conclusions are considered to be too far from experimental reality. Accurate modeling taking in account “reasonable” experimental details would be a worthwhile endeavor. 相似文献