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151.
Schürmann D. Di Leva A. Gialanella L. De Cesare M. De Cesare N. Imbriani G. D’Onofrio A Romano M. Romoli M. Terrasi F. 《The European Physical Journal A - Hadrons and Nuclei》2013,49(6):1-10
Using the Coulomb and proximity potential model (CPPM) we have investigated the cluster decays of the isotopes 212-240Pa, 219-245Np, 228-246Pu, 230-249Am and 232-252Cm leading to doubly magic 208Pb and its neighboring nuclei, which are not experimentally detected but which may be detectable in the future. It is found that most of the decays are favourable for experimental measurements (i.e., $T_{1/2}<10^{30}$ s) and this observation will serve as a guide to future experiments. Our study reveals the role of doubly magic 208Pb daughter nuclei and near doubly magic nuclei in the cluster decay process. In order to make a comparison with CPPM we also calculated the logarithmic half-lives using the Universal formula for the cluster decay (UNIV) by Poenaru et al., the Universal Decay Law (UDL) and the Scaling Law of Horoi et al., and they are found to be in good agreement. The Geiger-Nuttall plots of $log_{10}(T_{1/2})$ versus $Q^{-1/2}$ for various clusters from different isotopes of heavy parent nuclei have been studied and are found to be linear. 相似文献
152.
A stereospecific multicomponent reaction among isocyanides, syn-chlorooximes, and carboxylic acids provides an efficient synthesis of biologically relevant syn-α-oximinoamides. 相似文献
153.
We describe a simple and novel protocol for the synthesis of tetrahydro-1,4-benzodiazepin-2-ones with three points of diversity, exploiting the acylating properties of the recently rediscovered Ugi-imide. The final compounds can be easily prepared in three synthetic steps using a multicomponent reaction, a Staudinger reduction, and an acylative protocol, with good to excellent yields for each synthetic step. 相似文献
154.
Pisani C Itou M Sakurai Y Yamaki R Ito M Erba A Maschio L 《Physical chemistry chemical physics : PCCP》2011,13(3):933-936
The combination of new experimental and theoretical techniques provides evidence of instantaneous electron correlation effects in directional Compton profiles of crystalline silicon, which cannot be reproduced when reference is made to a density matrix obtained from a single-determinantal wavefunction. These effects are instead accounted for by a recently implemented post-Hartree-Fock periodic scheme, which gives results in quite good agreement with the high-quality experimental data. 相似文献
155.
Carboni S Gennari C Pignataro L Piarulli U 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4355-4373
The use of non covalent supramolecular ligand-ligand and ligand-substrate interactions in transition metal-catalysed transformations is a new, rapidly emerging area of research. Non-covalent interactions between monodentate ligands such as hydrogen bonding, coordinative bonding, ion pairing, π-π interactions and the formation of inclusion compounds, have been shown to impart higher activity and chemo-, regio-, and stereoselectivity to the corresponding transition metal complexes in a number of catalytic applications. Analogously, supramolecular ligand-substrate interactions, and particularly hydrogen bonding, have been used to direct the regio- and stereochemistry of several metal-catalysed reactions. The catalytic systems relying on supramolecular interactions are generally capable of self-assembling from simpler components in the environment where catalysis is to take place, and are therefore very well-suited for combinatorial catalyst discovery strategies and high-throughput screening. 相似文献
156.
Prof. Cristina Nativi Dr. Oscar Francesconi Gabriele Gabrielli Irene De Simone Dr. Benedetta Turchetti Dr. Lorenzo Di Cesare Mannelli Prof. Carla Ghelardini Prof. Pietro Buzzini Dr. Stefano Roelens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(16):5064-5072
The biological activity of a set of structurally related aminopyrrolic synthetic receptors for monosaccharides has been tested versus yeast and yeast‐like microorganisms and compared to their binding affinity toward mannosides. Antibiotic activity comparable to that of well‐known polyene (amphotericin B) or azole (ketoconazole) drugs has been found for some members of the family, along with a general correlation with binding abilities. A systematic structure–activity–affinity investigation shed light on the structural and functional requirements necessary for antibiotic activity and identified the tripodal compound 1 as the most potent compound of the set. Together with toxicity tests and inhibitor localization experiments performed through fluorescence microscopy, these studies led to the characterization of a new class of carbohydrate binding agents possessing antibiotic activity, in which pyrrolic groups precisely structured on a tripodal architecture appear to be responsible for permeability through the cell wall of pathogens, as well as for antibiotic activity inside the cytoplasm. 相似文献
157.
We report on the fabrication and characterization of a new generation of electro-switchable optofluidic devices based on flexible substrates, combined with the extraordinary properties of reconfigurable soft-materials. A conductive polydimethylsiloxane microstructure has been first sputtered with an Indium Tin Oxide (ITO) layer and then functionalized with an amorphous film of SiO(x). Then, the "layer" by "layer" microstructure has been infiltrated with an anisotropic and reconfigurable fluid (Nematic Liquid Crystal, NLC). The sample has been characterized in terms of morphological, optical and electro-optical properties: the soft-conductive microstructure exhibits a uniform and regular morphology, even after testing with mechanical stretching and deformations. Combination of the conductive ITO with the functionalization film (which has been employed for inducing in-plane alignment of NLC molecules) enables us to carry out a series of optical and electro-optical experiments; these confirm excellent properties in terms of a reconfigurable device and a diffractive element as well. 相似文献
158.
159.
Nativi C Francesconi O Gabrielli G De Simone I Turchetti B Mello T Di Cesare Mannelli L Ghelardini C Buzzini P Roelens S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(16):5064-5072
The biological activity of a set of structurally related aminopyrrolic synthetic receptors for monosaccharides has been tested versus yeast and yeast-like microorganisms and compared to their binding affinity toward mannosides. Antibiotic activity comparable to that of well-known polyene (amphotericin B) or azole (ketoconazole) drugs has been found for some members of the family, along with a general correlation with binding abilities. A systematic structure-activity-affinity investigation shed light on the structural and functional requirements necessary for antibiotic activity and identified the tripodal compound 1 as the most potent compound of the set. Together with toxicity tests and inhibitor localization experiments performed through fluorescence microscopy, these studies led to the characterization of a new class of carbohydrate binding agents possessing antibiotic activity, in which pyrrolic groups precisely structured on a tripodal architecture appear to be responsible for permeability through the cell wall of pathogens, as well as for antibiotic activity inside the cytoplasm. 相似文献
160.
In the present study the velocity profiles and the instability at the interface of a two phase water-oil fluid were investigated.
The main aim of the research project was to investigate the instability mechanisms that can cause the failure of an oil spill
barrier. Such mechanisms have been studied before for a vast variety of conditions (Wicks in Fluid dynamics of floating oil
containment by mechanical barriers in the presence of water currents. In: Conference on prevention and control of oil spills,
pp 55–106, 1969; Fannelop in Appl Ocean Res 5(2):80–92, 1983; Lee and Kang in Spill Sci Technol Bull 4(4):257–266, 1997; Fang and Johnston in J Waterway Port Coast Ocean Eng ASCE 127(4):234–239, 2001; among others). Although the velocity field in the region behind the barrier can influence the failure significantly, it
had not been measured and analyzed precisely. In the present study the velocity profiles in the vicinity of different barriers
were studied. To undertake the experiments, an oil layer was contained over the surface of flowing water by means of a barrier
in a laboratory flume. The ultrasonic velocity profiler method was used to measure velocity profiles in each phase and to
detect the oil–water interface. The effect of the barrier geometry on velocity profiles was studied. It was determined that
the contained oil slick, although similar to a gravity current, can not be considered as a gravity current. The oil–water
interface, derived from ultrasonic echo, was used to find the velocity profile in each fluid. Finally it was shown that the
fluctuations at the rearward side of the oil slick head are due to Kelvin–Helmholtz instabilities. 相似文献