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141.
142.
Christophe Chdru Bernard Decroix Jean Morel Frantisek Povazanec 《Journal of heterocyclic chemistry》1994,31(4):1027-1032
The 5,10-dihydro-4H-furo[3,2-e]pyrrolo[1,2-α][1,4]diazepin-5-one ( 7 ) and furo[3,2-e]pyrrolo[1,2-α][1,4]diaze-pine ( 10 ) are synthesized from suitable isocyanates 3a,b in acetic acid. The reactivity of 10 (C- and N-alkyla-tion) is investigated. 相似文献
143.
Dušan Malešev Zorica Radović Milena Jelikić-Stankov 《Monatshefte für Chemie / Chemical Monthly》1991,122(6-7):429-434
Summary Investigations on the composition of the molybdate(II)-3-hydroxyflavone complex and its stability constant have been carried out in 70% ethanolic solutions at room temperature (20°C), in the presence of a buffer atpH 6.30±0.05 and ionic strength 0.015. It has been found that a complex [MoO3(C15H9O3)
2
2–
] whose stability constant ranges from 15.13 atpH 6.25 to 13.02 atpH 7.00 is formed. Conditions are given for the determination of 3-hydroxyflavone by means of the reaction of complex formation in 50% ethanol atpH 6.60±0.05 and an ionic strength of 0.0225.
Untersuchung des Molybdat(II)-3-hydroxyflavon-Komplexes
Zusammenfassung Die Untersuchungen der Zusammensetzung des Komplexes und seiner Stabilitätskonstante wurden in 70% Ethanol, bei Raumtemperatur (20°C), in Anwesenheit von Puffer beipH=6.30±0.05 und der Ionenstärke 0.015 ausgeführt. Es wird der Komplex [MoO3(C15H9O3) 2 2– ] gebildet, die Stabilitätskonstanten reichen von 15.13 beipH 6.25 bis zu 13.02 beipH 7.00. Es wurden die Bedingungen zur quantitativen Bestimmung von 3-Hydroxyflavon mittels des Molybdenkomplexes in 50% Ethanol, beipH=6.60±0.05 und der Ionenstärke 0.0225 ermittelt.相似文献
144.
Ignatova M Voccia S Gilbert B Markova N Mercuri PS Galleni M Sciannamea V Lenoir S Cossement D Gouttebaron R Jérôme R Jérôme C 《Langmuir : the ACS journal of surfaces and colloids》2004,20(24):10718-10726
Novel copolymer brushes have been synthesized by a two-step "grafting from" method that consists of the electrografting of poly(2-phenyl-2-(2,2,6,6-tetramethyl-piperidin-1-yloxy)-ethylacrylate) onto stainless steel, followed by the nitroxide-mediated radical polymerization of 2-(dimethylamino ethyl)acrylate and styrene or n-butyl acrylate, initiated from the electrografted polyacrylate chains. The grafted copolymers were quaternized in order to endow them with antibacterial properties. Peeling tests have confirmed the strong adhesion of the grafted copolymer onto the stainless steel substrate. Quartz crystal microbalance experiments have proven that fibrinogen adhesion is lower on the hydrophilic quaternized films compared to the nonionic counterpart. Such quaternized copolymers exhibit significant antibacterial activity against the Gram-positive bacteria S. aureus and the Gram-negative bacteria E. coli. 相似文献
145.
Standard Gibbs free energies, enthalpies, and entropies for the dissociation of various aliphatic carboxylic acids are obtained through potnetiometric and calorimetric measurements in water-tert-butyl alcohol mixtures. Results are discussed in terms of solvent structural effects for the proton exchange reaction and in terms of the compensation law to explain enthalpic and entropic effects.Part I, ref 4; Part II,Thermochimica Acta
6, 283 (1973). 相似文献
146.
Yvon Pointud Jean Juillard Lèvon Avedikian Jean-Pierre Morel Michel Ducros 《Thermochimica Acta》1974,8(4):423-431
By using a calorimetric method, solution enthalpies of sodium, potassium, rubidium and cesium chlorides in mixtures containing from 0 to 45% by weight of alcohol are obtained. Standard enthalpies and transfer enthalpies are estimated. From previous data concerning Gibbs energies of transfer from water to the same solvent mixtures, transfer entropies are calculated. Enthalpies and entropies exhibit a maximum for molar fractions of about 0.07 of organic solvent. Results are discussed in terms of enhancement of the structuration of the aqueous network. 相似文献
147.
The role of the Mg2+ cation on huperzine molecule binding (drugs used for Alzheimer disease) on human serum albumin (HSA) was studied by affinity chromatography. The thermodynamic data corresponding to this binding were determined for a wide range of Mg2+ concentrations (x). For each solute, the huperzine binding on HSA was divided into two Mg2+ concentration regions. For a low x value, below xc (1.2 mM), the binding decrease with x. For x above xc the hydrophobic effect and van der Waals interactions between the huperzine molecule and the HSA implied a decrease in its binding. These results showed that for patients with Alzheimer disease, an Mg2+ supplementation during treatment with these huperzine molecules can increase the active pharmacological molecule concentration. 相似文献
148.
149.
The digital signal processing approaches were investigated as a preliminary indicator for discriminating between the protein coding and non-coding regions of DNA. This is because a three-base periodicity (TBP) has already been proven to exist in protein-coding regions arising from the length of codons (three nucleic acids). This demonstrates that there is a prominent peak in the energy spectrum of a DNA coding sequence at frequency rad/sample. However, because DNA sequences are symbolic sequences, these should be mapped into one or more signals such that the hidden information is highlighted. We propose, therefore, two new algorithms for computing adaptive mappings and, by using them, finding periodicities. Both such algorithms are based on the spectral envelope approach. This adaptive approach is essentially important since a single mapping for any DNA sequence may ignore its intrinsic properties. Finally, the improved performance of the new methods is verified by using them with synthetic and real DNA sequences as compared to the classical methods, especially the minimum entropy mapping (MEM) spectrum, which is also an adaptive method. We demonstrated that our method is both more accurate and more responsive than all its counterparts. This is especially important in this application since it reduces the risks of a coding sequence being missed. 相似文献
150.
Antonio Qualtieri Giovanni Morello Piernicola Spinicelli Maria T. Todaro Tiziana Stomeo Luigi Martiradonna Milena De Giorni Xavier Quélin Stéphanie Buil Alberto Bramati Jean P. Hermier Roberto Cingolani Massimo De Vittorio 《Superlattices and Microstructures》2010
Direct lithography of resist blends, embedding semiconductor colloidal nanocrystals (NCs) is an innovative way to achieve nanopositioning of NCs in quantum-confined optical resonators. In this work, we show a new appealing approach for the fabrication of single-photon sources operating at room temperature by localizing semiconductor colloidal NCs into vertical planar microcavities with lithographic techniques. 相似文献