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排序方式: 共有199条查询结果,搜索用时 156 毫秒
71.
Flavio Granato Matteo Scampicchio Andrea Bianco Saverio Mannino Chiara Bertarelli Giuseppe Zerbi 《Electroanalysis》2008,20(12):1374-1377
A new approach for the fabrication of disposable electrochemical surfaces is presented. Conducting fibers have been produced by a two‐step process. Firstly, a fine web mat composed of nylon‐6 and ferric chloride fibers (with diameters of about 200 nm) were electrospun on a flat collector. Afterwards, the electrospun mat was exposed to pyrrole vapor under controlled dry atmosphere until each nylon thread was fully coated with a conducting polypyrrole layer. The conducting fiber mat was finally integrated within an electrochemical cell and used as a disposable sensor device. The suitability of the sensor was tested using phosphate and carbonate organic anions. The large scale fabrication of conducting tissue, in the form of a fine web of spun nanofibers, is relatively fast and inexpensive, and it paves the way to the build up of new disposable electrodes. 相似文献
72.
Capriati V Florio S Luisi R Perna FM Barluenga J 《The Journal of organic chemistry》2005,70(15):5852-5858
A diastereo- and enantiospecific formation of tetrasubstituted cyclopropane carbene complexes and cyclopropanecarboxylates from lithiated aryloxiranes and alpha,beta-unsaturated Fischer carbene complexes is described. 相似文献
73.
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75.
Rossella Basilotta Deborah Mannino Alessia Filippone Giovanna Casili Angela Prestifilippo Lorenzo Colarossi Gabriele Raciti Emanuela Esposito Michela Campolo 《Molecules (Basel, Switzerland)》2021,26(13)
Since cancer is a multifactorial disease with a high mortality rate, the study of new therapeutic strategies is one of the main objectives in modern research. Numerous chemotherapeutic agents, although widely used, have the disadvantage of being not very soluble in water or selective towards cancerous cells, with consequent side effects. Therefore, in recent years, a greater interest has emerged in innovative drug delivery systems (DDSs) such as calixarene, a third-generation supramolecular compound. Calixarene and its water-soluble derivatives show good biocompatibility and have low cytotoxicity. Thanks to their chemical–physical characteristics, calixarenes can be easily functionalized, and by itself can encapsulate host molecules forming nanostructures capable of releasing drugs in a controlled way. The encapsulation of anticancer drugs in a calixarene derivate improves their bioavailability and efficacy. Thus, the use of calixarenes as carriers of anticancer drugs could reduce their side effects and increase their affinity towards the target. This review summarizes the numerous research advances regarding the development of calixarene nanoparticles capable of encapsulating various anticancer drugs. 相似文献
76.
Saverio Pascazio 《Foundations of Physics》1997,27(12):1655-1670
The quantum Zeno effect is often studied and understood in term of nonunitary evolutions, involving projections à la von Neumann
(measurements). We propose a dynamical explanation of this effect, which involves only unitary operators. The limit of infinitely
frequent measurements is critically discussed: it is unphysical, yet interesting and peculiar. 相似文献
77.
Summary The evolution of non linear small perturbations in a charged fluid with generalized Ohm's law is considered, pointing out
the possibility of effects due to interaction between different waves. Following the perturbative reductive methods, some
phase functions for studying interaction are introduced. A suitable hypothesis on their evolution permits us to prove that
the amplitudes of the first order perturbation obey Burgers-like equations, in which the dissipative terms are not influenced
by the Hall effect.
Riassunto Si studia l'evoluzione di piccole perturbazioni in un sistema M.F.D. con legge di Ohm generalizzata, prendendo in considerazione gli effetti della mutua interazione tra onde appartenenti a differenti famiglie di caratteristiche. Mediante tecniche di tipo perturbativo riduttivo e con l'introduzione di opportune funzioni di fase, si mostra che le ampiezze delle perturbazioni sono regolate, in prima approssimazione, da equazioni del tipo di Burgers in cui i termini dissipativi non dipendono dall'effetto Hall.相似文献
78.
Marabotti A Spyrakis F Facchiano A Cozzini P Alberti S Kellogg GE Mozzarelli A 《Journal of computational chemistry》2008,29(12):1955-1969
Despite decades of investigations, it is not yet clear whether there are rules dictating the specificity of the interaction between amino acids and nucleotide bases. This issue was addressed by determining, in a dataset consisting of 100 high-resolution protein-DNA structures, the frequency and energy of interaction between each amino acid and base, and the energetics of water-mediated interactions. The analysis was carried out using HINT, a non-Newtonian force field encoding both enthalpic and entropic contributions, and Rank, a geometry-based tool for evaluating hydrogen bond interactions. A frequency- and energy-based preferential interaction of Arg and Lys with G, Asp and Glu with C, and Asn and Gln with A was found. Not only favorable, but also unfavorable contacts were found to be conserved. Water-mediated interactions strongly increase the probability of Thr-A, Lys-A, and Lys-C contacts. The frequency, interaction energy, and water enhancement factors associated with each amino acid-base pair were used to predict the base triplet recognized by the helix motif in 45 zinc fingers, which represents an ideal case study for the analysis of one-to-one amino acid-base pair contacts. The model correctly predicted 70.4% of 135 amino acid-base pairs, and, by weighting the energetic relevance of each amino acid-base pair to the overall recognition energy, it yielded a prediction rate of 89.7%. 相似文献
79.
A disposable, small scale and low-cost electrochemical "wall-jet" flow-cell was build up together with a graphite lead mounted onto a pencil holder able to modulate the current response by the control of the surface area of the electrode. The total phenolic content of different types of tea infusions was determined and compared with the conventional Folin-Ciocolteau method. An index of antioxidant power was also proposed and data were compared with those obtained by the DPPH* assay. 相似文献
80.