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排序方式: 共有84条查询结果,搜索用时 78 毫秒
1.
Kleandrova Valeria V. Rojas-Vargas Julio A. Scotti Marcus T. Speck-Planche Alejandro 《Molecular diversity》2022,26(5):2523-2534
Molecular Diversity - Hypertension is a medical condition that affects millions of people worldwide. Despite the high efficacy of the current antihypertensive drugs, they are associated with... 相似文献
2.
The new hexaalkylborazine chromium tricarbonyls (n-Pr)3B3N3Me3Cr(CO)3 (V), Me3B3N3(n-Pr)3Cr(CO)3 (VI), (i-Pr)3B3N3Me3Cr(CO)3 (VII) and Me3B3N3(i-Pr)3Cr(CO)3 (VIII) have been prepared from fac-Cr(CO)3(MeCN)3 and the corresponding borazine in dioxane or without solvent. They are much more labile than the isomeric complex Et3B3N3Et3Cr(CO)3 (IV) which can be readily obtained from Et3B3N3Me3Cr(CO)3 and Et3B3N3Et3 by ring ligand exchange. The NMR., IR., UV. and Mass spectroscopic data of the complexes IV–VIII will be briefly discussed. The preparation of the borazine derivatives (n-Pr)3B3N3Me3 (IX) and Me3B3N3(n-Pr)3 (X) is also reported. 相似文献
3.
Me3B3N3H3Cr(CO)3 has been obtained by ring-ligand exchange starting from Et3B3N3Me3Cr(CO)3 and Me3B3N3H3. The new compound has been characterised by means of their IR, NMR, UV and mass spectroscopic data. 相似文献
4.
S. Mercone L. Mchin C.A. Perroni J.M. Routoure U. Scotti di Uccio L. Maritato V. Cataudella 《Progress in Solid State Chemistry》2007,35(2-4):387-396
The resistivity of thin La0.7Sr0.3MnO3 films was first investigated in a wide temperature (T) range (10–750 K). Films grown by different techniques and on several substrates enabled to analyze samples with different amounts of disorder. The aim of this work was to elucidate the nature of the metal–insulator (M–I) transition occurring at T = Tp in these films and its relation with the different kinds of inhomogeneities they could present like intrinsic electric disorder and co-existence of two different electrical and/or magnetic phases. The low-temperature resistivity state was described mostly by a law which scales as T with ≈ 2.5. This supports the theoretical proposal of single magnon scattering in presence of minority spin states localized by the disorder. In the whole range of temperatures the experimental data are found to be consistent with a phase separation (PS) scenario. In order to go through the origin of the characteristic length scale of inhomogeneity found, preliminarily low frequency noise measurements as a function of T in a range of temperature around the M–I transition were made. The samples used were patterned using photolithography into bridges with various widths and lengths. No clear sign of separation phase dynamic has been observed in our noise measurements. Unexpectedly the normalized Hooge parameter H/n was found not to be volume (Ω) independent. The LSMO electrical properties may strongly be driven by disorder and new design for magnetoresistance sensors may have to take into account their intrinsic PS. 相似文献
5.
The PF6 salts of the new cationic hexamethylborazinerhodium(I) complexes of general formula [Rh(Me3B3N3Me3)(LL′)]+ (LL′= 1,5-cyclooctadiene, norbornadiene, tetrafluorobenzobarrelene, trimethyltetrafluorobenzobarrelene, L = L′ = ethylene, CO) have been prepared from the reaction between [RhCl(LL′)]2, Me3B3NMe3, and AgPF6 in dichloromethane. These complexes are very labile, undergoing rapid ring ligand exchange in solution with σ and π-donor ligands. The synthesis of [Rh(η6-naphthalene)(COD)]PF6 is also described. The properties and NMR and IR spectroscopic characteristics of the new compounds are briefly discussed. 相似文献
6.
Lorenzo Mirizzi Mattia Carnevale Massimiliano DArienzo Chiara Milanese Barbara Di Credico Silvia Mostoni Roberto Scotti 《Molecules (Basel, Switzerland)》2021,26(12)
The development of effective thermally conductive rubber nanocomposites for heat management represents a tricky point for several modern technologies, ranging from electronic devices to the tire industry. Since rubber materials generally exhibit poor thermal transfer, the addition of high loadings of different carbon-based or inorganic thermally conductive fillers is mandatory to achieve satisfactory heat dissipation performance. However, this dramatically alters the mechanical behavior of the final materials, representing a real limitation to their application. Moreover, upon fillers’ incorporation into the polymer matrix, interfacial thermal resistance arises due to differences between the phonon spectra and scattering at the hybrid interface between the phases. Thus, a suitable filler functionalization is required to avoid discontinuities in the thermal transfer. In this challenging scenario, the present review aims at summarizing the most recent efforts to improve the thermal conductivity of rubber nanocomposites by exploiting, in particular, inorganic and hybrid filler systems, focusing on those that may guarantee a viable transfer of lab-scale formulations to technological applicable solutions. The intrinsic relationship among the filler’s loading, structure, morphology, and interfacial features and the heat transfer in the rubber matrix will be explored in depth, with the ambition of providing some methodological tools for a more profitable design of thermally conductive rubber nanocomposites, especially those for the formulation of tires. 相似文献
7.
Eric Mayer-Santos Tatjana Maravic Allegra Comba Patricia Moreira Freitas Giovanna Bueno Marinho Claudia Mazzitelli Edoardo Mancuso Nicola Scotti Federica Florenzano Lorenzo Breschi Annalisa Mazzoni 《Molecules (Basel, Switzerland)》2022,27(5)
This study aimed to investigate matrix metalloproteinase (MMP) activity in human dentin using in-situ and gelatin zymography, after at-home and in-office bleaching, related to their clinical exposure times. Dentin specimens (n = 5) were treated with 35% hydrogen peroxide (50 min per session/4 sessions), 10% carbamide peroxide (180 min/21 sessions), or no treatment. All were subjected to in-situ zymography. Dentin slices were, subsequently, obtained, covered with fluorescein-conjugated gelatin, and examined with confocal laser-scanning microscopy. The fluorescence intensity was quantified and statistically analyzed using one-way ANOVA and Bonferroni tests (α = 0.05). Furthermore, gelatin zymography was performed on protein extracts obtained from dentin powder (N = 8 teeth), treated with hydrogen peroxide or carbamide peroxide, with different exposure times (10/50 min for hydrogen peroxide; 252/1260 min for carbamide peroxide). The results of the in-situ zymography showed no statistical differences between the bleached specimens and the control group, with a medium level of gelatinolytic activity expressed in the dentin tubules. The results of gelatin zymography showed an increased expression of pro-MMP-9 in carbamide peroxide groups. The expression of pro-MMP-2 decreased in all the experimental groups. The bleaching treatments performed on the enamel of sound teeth do not influence dentinal enzymatic activity. However, when unprotected dentin tissue is bleached, matrix metalloproteinases are more expressed, particularly when carbamide peroxide is used, proportional to the exposure time. 相似文献
8.
9.
Method for intracellular magnetic labeling of human mononuclear cells using approved iron contrast agents 总被引:2,自引:0,他引:2
Sipe JC Filippi M Martino G Furlan R Rocca MA Rovaris M Bergami A Zyroff J Scotti G Comi G 《Magnetic resonance imaging》1999,17(10):911-1523
A method for intracellular iron labeling of human mononuclear cells (lymphocytes and monocytes) for magnetic resonance imaging (MRI) using simple incubation of cells with approved MRI iron contrast agents is presented. Labeled cells can be detected by MRI in vitro, and this suggests the possibility that the technique could become a marker for in vivo lymphocyte and monocyte trafficking studies in acute inflammatory lesions such as those in Multiple Sclerosis. 相似文献
10.
Canevali C Mari CM Mattoni M Morazzoni F Nodari L Ruffo R Russo U Scotti R 《The journal of physical chemistry. B》2005,109(15):7195-7202
The mechanism of NO interaction with nanosized Ru(Pd,Pt)-doped SnO(2) was studied by electron paramagnetic resonance, M?ssbauer, and electric resistance measurements. Three steps were proposed for the reaction between the semiconductor oxide and the gaseous component: (i) the formation of bielectronic oxygen vacancies (V(o)) in SnO(2); (ii) their single-ionization (V(o)(*)) with injection of electrons into the SnO(2) conduction band; (iii) the subsequent transfer of electrons from V(o)(*) to [Ru(Pd,Pt)](4+). The last process induces the formation of further oxygen vacancies which reduce the transition metal centers to lower oxidation states; the redox processes is enhanced and the electrical resistance in transition metal-doped SnO(2) is stronger modified with respect to the undoped material. 相似文献