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排序方式: 共有421条查询结果,搜索用时 171 毫秒
191.
In this paper we present exact results for the critical exponents of interacting self-avoiding walks with ends at a linear boundary. Effective interactions are mediated by vacancies, correlated and uncorrelated, on the dual lattice. By choosing different boundary conditions, several ordinary and special regimes can be described in terms of clusters geometry and of critical and lowtemperature properties of the
model. In particular, the problem of boundary exponents at the -point is fully solved, and implications for-point universality are discussed. The surface crossover exponent at the special transition of noninteracting self-avoiding walks is also interpreted in terms of percolation dimensions. 相似文献
192.
Maria Rosaria Iesce Rosalia Sferruzza Flavio Cermola Marina DellaGreca 《Helvetica chimica acta》2016,99(4):296-301
Furanyl alcohols react with arenes by a variant of the Friedel–Crafts reaction to give benzyl furans with fairly satisfying yields. The reaction is mediated by Tf2O and occurs with reduced times in the presence of Ph3PO. Some prepared compounds exhibit a lignan‐like backbone. 相似文献
193.
Press‐Printed Conductive Carbon Black Nanoparticle Films for Molecular Detection at the Microscale
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Flavio Della Pelle Dr. Luis Vázquez Prof. Michele Del Carlo Prof. Manuel Sergi Prof. Dario Compagnone Prof. Alberto Escarpa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12761-12766
Carbon black nanoparticle (CBNP) press‐transferred film‐based transducers for the molecular detection at the microscale level were proposed for the first time. Current‐sensing atomic force microscopy (CS‐AFM) revealed that the CBNP films were effectively press‐transferred, retaining their good conductivity. A significant correlation between the morphology and the resistance was observed. The highest resistance was localized at the top of the press‐transferred film protrusions, whereas low values are usually obtained at the deep crevices or grooves. The amount of press‐transferred CBNPs is the key parameter to obtain films with improved conductivity, which is in good agreement with the electrochemical response. In addition, the conductivity of such optimum films was not only Ohmic; in fact, tunneling/hopping contributions were observed, as assessed by CS‐AFM. The CBNP films acted as exclusive electrochemical transducers as evidenced by using two classes of molecules, that is, neurotransmitters and environmental organic contaminants. These results revealed the potential of these CBNP press‐transferred films for providing new options in microfluidics and other related micro‐ and nanochemistry applications. 相似文献
194.
195.
Norberto Garcia‐Cairasco Miguel Moyses‐Neto Flavio DelVecchio Jos A. C. Oliveira Francisco L. dosSantos Olagide W. Castro Gabriel M. Arisi Mrcio Dantas Ruither O. G. Carolino Joaquim Coutinho‐Netto Andre L. A. Dagostin Marcelo C. A. Rodrigues Ricardo M. Leo Samir A. P. Quintiliano Luiz F. Silva Leonardo Gobbo‐Neto Norberto P. Lopes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(49):12981-12981
196.
Dickson Maria Michela Espa Giuseppe Giuliani Diego Santi Flavio Savadori Lucia 《Nonlinear dynamics》2020,101(3):1833-1846
Nonlinear Dynamics - This paper aims at investigating empirically whether and to what extent the containment measures adopted in Italy had an impact in reducing the diffusion of the COVID-19... 相似文献
197.
Bogdan Cramariuc Radu Cramariuc Roxana Scarlet Liliana Rozemarie Manea Iuliana G. Lupu Oana Cramariuc 《Journal of Electrostatics》2013,71(3):189-198
In order to increase the control on the fiber diameter we propose in this paper a methodology to determine stability domains of the process in which the electrospun fiber diameter can be predetermined and also controlled by means of the polymer solution flow and the applied voltage. To define these stability domains we employ a combination of analytical expressions depending on the location along the traveling jet. In the vicinity of the nozzle we employ the expression which links the fiber diameter with the kinematic viscosity of the polymer solution, nozzle-collector distance, solution density, liquid flow, electric current and intensity of the electrostatic field. At larger distances from the nozzle, the fiber diameter can be expressed as a function of solution density, liquid flow, intensity of the applied electrostatic field and distance from the nozzle. Close to the collector the fiber diameter can be expressed with respect to the superficial tension of the polymer solution, dielectric permittivity, liquid flow and intensity of the electric current. Under specific constrains, the superposition of the plots obtained from these mathematical expressions will be used to determine the stability domain for the fiber diameter in which the diameter can be controlled by two process parameters, namely applied voltage and polymer solution flow. Through this approach the present paper can contribute to increased control of the electrospinning process and thus enhanced applicability. 相似文献
198.
Gabriel Cendejas Csar Andrs Flores-Sandoval Nelson Huitrn Rafael Herrera Luis S. Zamudio-Rivera Hiram I. Beltrn Flavio Vzquez 《Journal of Molecular Structure》2008,879(1-3):40-52
In this work, the influence of three different initiators (KOH, KOH dissolved in ethanol and the potassium salt of ethylene glycol) on the propylene oxide polymerization was studied by experimental and theoretical methods. A first series of reactions was carried out to establish the adequate thermal conditions for a minimal monomer transfer during the polymerization. The formation of end insaturations (main consequence of the monomer transfer interference) in the poly(propylene oxide) chains was studied by spectroscopic methods. Furthermore, a second series of poly(propylene oxide)s was prepared by using the mentioned initiators, and characterized by size exclusion chromatography. The initiator efficiency to create active centers in every reactive system was determined from the molecular weight and the conversion data obtained. Experimental results were elucidated by using quantum chemical calculations at density functional theory level, involving thermo-chemistry parameters, and the simulation of the infrared, and 13C nuclear magnetic resonance spectra. This method led to studying the addition of up to ten propylene oxide unit, resulting into important energetic tendencies and regioselectivity, being compared to the physicochemical data of products obtained. These correlations meant further understanding of the reaction course and the type of products obtained, depending on the nature of the initiator. 相似文献
199.
Adele Mucci Luisa Schenetti Maria A. Vandelli Barbara Ruozi Gianfranco Salvioli Flavio Forni 《Supramolecular chemistry》2013,25(4):427-433
Abstract The formation and geometry of the hyodeoxycholic acid (HDCA)/2-hydroxypropyl-β-cyclodextrin (HPβCD) complex in methanol-d4 solution was determined through a rotating frame nuclear Overhauser (ROESY) experiment. The reported results confirmed those independently and previously obtained though the use of 13C complexation shifts in the same solvent. The 13C approach, which needs shorter experimental times and is currently used in the study of HPβCD/bile acid systems, was then substantiated. 相似文献
200.
Cazzani Antonio Serra Mauro Stochino Flavio Turco Emilio 《Continuum Mechanics and Thermodynamics》2020,32(3):665-692
Continuum Mechanics and Thermodynamics - This work discusses some alternate models of a mixed assumed strain finite element which has been developed for laminated plates. After a brief theoretical... 相似文献