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排序方式: 共有626条查询结果,搜索用时 8 毫秒
31.
Prof. Nunzio Tuccitto Gaetano Catania Prof. Andrea Pappalardo Dr. Giuseppe Trusso Sfrazzetto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(55):13715-13718
The supramolecular detection by image analysis of a simulant chemical warfare agent on a solid device containing a selective molecular sensor based on a BODIPY scaffold is reported. The recognition properties were investigated in solution, demonstrating high affinity (log K 6.60) and sensitivity (LOD 10 ppt). A test strip also confirmed the sensing properties in gas phase. Image analysis of the solid device allows quantitative information about the simulant to be obtained, recovering the sensor almost 5 times and thus confirming the goal of the supramolecular approach. 相似文献
32.
Franco Cristiani Francesco A. Devillanova Angelo Diaz Francesco Isaia Gaetano Verani 《Heteroatom Chemistry》1990,1(5):363-367
Using a series of N-methylated thiohydantoins as substrates, the donor properties of the sulfur atom are measured by determining the stability constants (K) of their adducts with molecular iodine. The K's have been determined by recording the UV-visible spectra of several CH2Cl2 solutions with different amounts of the reagents. The experimental data fit the 1:1 adduct model for all the compounds. The K values, compared with those previously found for the unsubstituted hydantoins and with those obtained for 5-methyl-2-thiohydantoin, show that the hydrogen-bonding interaction between the NH hydrogen and the S-bonded iodine plays an important role in determining the stability of the adduct. The K values obtained for several pentaatomic rings, all containing the thioureido group HN C() NH , are discussed on the basis of the influence of the substituents at C-4 and C-5 on the donor properties of the sulfur atom. 相似文献
33.
Sheng Yang Guangbo Chen Antonio Gaetano Ricciardulli Panpan Zhang Zhen Zhang Huanhuan Shi Ji Ma Jian Zhang Paul W. M. Blom Xinliang Feng 《Angewandte Chemie (International ed. in English)》2020,59(1):465-470
Transition‐metal phosphides (TMPs) have emerged as a fascinating class of narrow‐gap semiconductors and electrocatalysts. However, they are intrinsic nonlayered materials that cannot be delaminated into two‐dimensional (2D) sheets. Here, we demonstrate a general bottom‐up topochemical strategy to synthesize a series of 2D TMPs (e.g. Co2P, Ni12P5, and CoxFe2?xP) by using phosphorene sheets as the phosphorus precursors and 2D templates. Notably, 2D Co2P is a p‐type semiconductor, with a hole mobility of 20.8 cm2 V?1 s?1 at 300 K in field‐effect transistors. It also behaves as a promising electrocatalyst for the oxygen evolution reaction (OER), thanks to the charge‐transport modulation and improved surface exposure. In particular, iron‐doped Co2P (i.e. Co1.5Fe0.5P) delivers a low overpotential of only 278 mV at a current density of 10 mA cm?2 that outperforms the commercial Ir/C benchmark (304 mV). 相似文献
34.
Using diffusion Monte Carlo simulations we have investigated the ground state of a symmetric electron-hole bilayer and determined its phase diagram at T = 0. We find clear evidence of an excitonic condensate, whose stability however is affected by an in-layer electronic correlation. This stabilizes the electron-hole plasma at large values of the density or interlayer distance, and the Wigner crystal at low density and large distance. We have also estimated pair correlation functions and low-order density matrices to give a microscopic characterization of correlations as well as to try and estimate the condensate fraction. 相似文献
35.
Alfredo De Rossi Gaetano Assanto Stefano Trillo William E. Torruellas 《Optics Communications》1998,150(1-6):390-398
We have identified a family of (2+1)D spatial solitary waves which can stably propagate in bulk media in the presence of coexisting diffraction, self-focusing Kerr and quadratic nonlinearities. In a conspicuous range of excitation conditions close to the stationary solutions, the emerging wavepackets are immune to the detrimental occurrence of filamentation and collapse, typical of pure Kerr media. The presence of a second-order contribution to the cubic nonlinear response is, therefore, able to prevent optical damage in applications relying on self-guidance. We show that the cross-phase modulation plays an important effect on stability. Our estimate shows that the effects of the cubic susceptibility cannot be neglected below a certain beam size in realistic crystals (e.g. KTP or similar). 相似文献
36.
Gaetano Zingone 《Meccanica》1972,7(2):117-123
Summary The limit analysis of indefinite plates resting on a continuous elastoplastic medium and subjected to a load distributed over a partial surface with a circular boundary yields the fundamental equation governing the problem. Minimum conditions are set and the solution that supplies the collapse load of the plate-soil system is found by variational calculus.
This research was supported by the CNR (National Research Council). 相似文献
Sommario Si analizza lo stato limite delle piastre indefinite, appoggiate su un mezzo elastoplastico continuo e sottoposte a carico ripartito su una superficie parziale a contorno circolare, pervenendo all'equazione fondamentale che regge il problemaImponendo quindi delle condizioni minimizzanti, si trova, tramite il calcolo variazionale, la soluzione che fornisce il carico di collasso del sistema piastra-suolo.
This research was supported by the CNR (National Research Council). 相似文献
37.
Gaetano Liso Giuseppe Trapani Vincenza Berardi Andrea Latrofa Paolo Marchini 《Journal of heterocyclic chemistry》1980,17(4):793-796
The reaction between 2-aminothiophenol 1 and acetylenic nitriles or esters 2a-d leads to the vinyl thio-ethers 3a-d. The conversion of 3 into benzothiazoles 8 and/or 1,4-benzothiazines 9 , in boiling dimethyl sulfoxide, has been achieved. A possible pathway involving benzothiazolines 5 as key intermediates is suggested. 相似文献
38.
Gaetano Villari 《Annali di Matematica Pura ed Applicata》1966,73(1):103-110
Sommario. Si studia il problema della esistenza di soluzioni armoniche per una classe di equazioni differenziali periodiche del terz’
ordine di tipo quasi lineare, e si stabilisce un criterio di esistenza che estende precedenti risultati.
Ricerca eseguita nell’ambito del Gruppo di Ricerca n. 11 del Comitato per la Matematica del C. N. R. 相似文献
39.
Bolognese A Correale G Manfra M Lavecchia A Novellino E Barone V 《Organic & biomolecular chemistry》2004,2(19):2809-2813
Microwave irradiation of a mixture of benzylidene-anilines and mercaptoacetic acid in benzene gives 1,3-thiazolidin-4-ones in very high yield (65-90%), whereas the same reaction performed through using the conventional method, at reflux temperature, requires a much longer time and gives a much lower yield (25-69%). This difference seems to be due to some intermediates and by-products formed during the conventional reaction. On the basis of 1H NMR studies, two different mechanisms, acting in benzene and in DMF, respectively, have been hypothesized for the thiazolidin-4-one system formation. 相似文献
40.
The reaction of O-alkylated p-aminocalix[n]arenes (n=4, 6, 8) with N,N′-di(tert-butoxycarbonyl)thiourea in the presence of HgCl2 and subsequent removal of the protective groups with hydrochloric acid led to the new water soluble calix[n]guanidinium derivatives (p-guanidiniumcalix[n]arenes) 20-23. With the exception of tetraoctyl-p-guanidiniumcalix[4]arene 21, which forms a macroscopic gelatinous aggregate even at very low concentration, all the synthesised guanidinium calixarenes show good solubility in water and sharp NMR signals. Moreover, these compounds are not cytotoxic and bind to plasmid DNA. 相似文献