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排序方式: 共有473条查询结果,搜索用时 339 毫秒
21.
Ilana Perelshtein Yelena Ruderman Nina Perkas Jamie Beddow Gagandeep Singh Mircea Vinatoru Eadaoin Joyce Timothy J. Mason María Blanes Korina Mollá Aharon Gedanken 《Cellulose (London, England)》2013,20(3):1215-1221
Hospital-acquired nosocomial infections are a major health, and consequently financial issue, in the world healthcare system. The problem of bacterial infections in general, and in hospitals in particular, has led to extensive scientific and industrial efforts to fabricate antibacterial textiles. A sonochemical coating machine was developed and built and its ability to coat antibacterial nanoparticles (NPs) onto 40–50 meter length of materials on a roll to roll basis at a speed of 22 cm/min. Cotton coated sonochemically with copper oxide nanoparticles (CuO NPs) was found to maintain its antibacterial properties even after 65 cycles of washings according to hospital protocols of hygienic washing (75 °C). This demonstrates the good quality and high stability of this sonochemically produced NPs coating on textiles. Durable antibacterial textiles such as these may be suitable for wide spread use in future hospital environments where hygiene control is of paramount importance. 相似文献
22.
Mihaela Vlassa Gheorghe Borodi Cristian Silvestru Mircea Vlassa 《Central European Journal of Chemistry》2014,12(1):14-24
Reaction of Na4TCM (1) (H4TCM = tetra[4-(carboxyphenyl)oxamethyl]methane) with [Cu(CHA)](ClO4)2 (2)(CHA = 1,3,6,8,11,14-hexaaz atricyclo[12.2.1.1.8,11] octadecane) in a DMF-water mixture yields [Cu(CHA)]2[TCM] (3). Structural analysis of [Cu(CHA)]2[TCM]·11H2O (3·11H2O) by single crystal X-ray diffraction reveals strong copper-oxygen bonds between two complex cations and the tetraanion leading to a 3D coordination network (zwitterionic structure), consolidated through additional NH...O=C hydrogen bonding within the cation/anion association. The resulting coordination geometry around a copper atom is a distorted square pyramidal with an oxygen atom of the anionic ligand in the apical position. A 3D supramolecular network is developed in the crystal based only on NH...OC hydrogen bonds between the macrocyclic metallic tecton and the carboxylate groups of neighboring 3D coordinated (zwitterionic) moieties. The pseudotetrahedral TCM4? tetraanionic ligand induces a diamondoid architecture formed of large distorted adamantanoid cages. 相似文献
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Carl K. Brozek Dr. Luca Bellarosa Tomohiro Soejima Talia V. Clark Prof. Núria López Prof. Mircea Dincă 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):6871-6874
We investigated which factors govern the critical steps of cation exchange in metal–organic frameworks by studying the effect of various solvents on the insertion of Ni2+ into MOF‐5 and Co2+ into MFU‐4l. After plotting the extent of cation insertion versus different solvent parameters, trends emerge that offer insight into the exchange processes for both systems. This approach establishes a method for understanding critical aspects of cation exchange in different MOFs and other materials. 相似文献
25.
Adrian Pîrnău Mihaela Mic Mircea Bogdan Ioan Turcu 《Journal of inclusion phenomena and macrocyclic chemistry》2014,79(3-4):283-289
The inclusion of local anesthetic drug procaine hydrochloride by β-cyclodextrin was investigated by 1D and 2D proton NMR spectroscopy and isothermal titration calorimetry (ITC) at 298 K. The stoichiometry of the complex was determinate by the method of continuous variation, using the chemical induced shift of both host and guest protons. The association constant K, of the obtained complex was calculated and found to be 293.17 M?1. Rotating frame NOE spectroscopy, was used to ascertain the solution geometry of the host–guest complex. The result reveals that the procaine molecule penetrates into the β-cyclodextrin cavity with the aromatic ring. The energetics of complexation process is investigated by ITC technique. The analysis indicates that the complexation of procaine by β-CD is an exothermic process and show that both enthalpy and entropy contribute to the binding process. The obtained value for the association constant is in good agreement with that obtained from NMR. 相似文献
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Mircea Grigoriu 《Journal of computational physics》2010,229(22):8406-8429
Mathematical requirements that the random coefficients of stochastic elliptical partial differential equations must satisfy such that they have unique solutions have been studied extensively. Yet, additional constraints that these coefficients must satisfy to provide realistic representations for physical quantities, referred to as physical requirements, have not been examined systematically. 相似文献
29.
Tinnefeld P Weston KD Vosch T Cotlet M Weil T Hofkens J Müllen K De Schryver FC Sauer M 《Journal of the American Chemical Society》2002,124(48):14310-14311
The photophysics of a dendrimer containing four chromophores are investigated at the single-molecule level. First, the multichromophoric character of single dendrimers' absorption is probed by modulating the linear polarization of the excitation beam. Subsequently, using circular polarization, the same dendrimers are excited, and their fluorescence transients are recorded. Using pulsed excitation in combination with the classical Hanbury-Brown and Twiss coincidence setup the presented data demonstrate that efficient singlet-singlet annihilation ensures that always only one photon is emitted even when several excitations are generated in an individual multichromophoric molecule. 相似文献
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