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1.
Peter Schiess Charles Monnier Peter Ringele Ebrahim Sendi 《Helvetica chimica acta》1974,57(6):1676-1691
Addition of phenyl-, alkyl-, alkenyl- and alkinyl-Grignard reagents to pyridine-N-oxide in THF leads to 5-substituted (2Z, 4E)-pentadien-aldoximes 6 having (E) (syn)-configuration of the C, N-double bond. The unsaturated oximes are shown to arise through an electrocyclic ring opening reaction from the primary Grignard adducts 5 . These can be trapped by protonation at low temperature. 相似文献
2.
Nesrine Mechi Ismahen Ben Khemis Houcine Dhaou Slim Zghal Abdelmottaleb Ben Lamine 《Chinese Journal of Physics (Taipei)》2018,56(2):449-467
The Mg50Ni45Cr5 alloy for hydrogen storage is prepared by mechanical alloying. First, using the X-ray diffraction (XRD) and the scanning electron microscopy (SEM) we examine the morphology and the structure of the substrate. The obtained results highlight the effectiveness of this alloy in loading hydrogen as it is a nanocrystalline and a ductile one. Second, we attempt to justify these expectations using the statistical physic, precisely the model monolayer with two levels of energy, in modeling a hydrogen absorption and desorption isotherms on Mg50Ni45Cr5 alloy at four temperatures T?=?275?K, T?=?300?K, T?=?325?K and T?=?350?K. The model has six physicochemical parameters deduced from the fitting of the isotherms, they are divided by two categories of steric and energetic parameters. Thanks to these parameters we compare the absorption and desorption processes, in order to highlight the hysteresis phenomenon encountered during the hydrogen sorption. 相似文献
3.
Bouhali Nesrine Azzam-Laouir Dalila Monteiro Marques Manuel D. P. 《Journal of Optimization Theory and Applications》2022,194(1):59-91
Journal of Optimization Theory and Applications - We consider a control problem in a finite-dimensional setting, which consists in finding a minimizer for a standard functional defined by way of... 相似文献
4.
Alonso S Sendiña-Nadal I Pérez-Muñuzuri V Sancho JM Sagués F 《Physical review letters》2001,87(7):078302
A pacemaker, regularly emitting chemical waves, is created out of noise when an excitable photosensitive Belousov-Zhabotinsky medium, strictly unable to autonomously initiate autowaves, is forced with a spatiotemporal patterned random illumination. These experimental observations are also reproduced numerically by using a set of reaction-diffusion equations for an activator-inhibitor model, and further analytically interpreted in terms of genuine coupling effects arising from parametric fluctuations. Within the same framework we also address situations of noise-sustained propagation in subexcitable media. 相似文献
5.
Nesrine Fterich 《Applications of Mathematics》2010,55(1):1-46
The article deals with a nonlinear generalized Ginzburg-Landau (Allen-Cahn) system of PDEs accounting for nonisothermal phase
transition phenomena which was recently derived by A. Miranville and G. Schimperna: Nonisothermal phase separation based on
a microforce balance, Discrete Contin. Dyn. Syst., Ser. B, 5 (2005), 753–768. The existence of solutions to a related Neumann-Robin problem is established in an N ⩽ 3- dimensional space
setting. A fixed point procedure guarantees the existence of solutions locally in time. Next, Sobolev embeddings, interpolation
inequalities, Moser iterations estimates and results on renormalized solutions for a parabolic equation with L
1 data are used to handle a suitable a priori estimate which allows to extend our local solutions to the whole time interval.
The uniqueness result is justified by proper contracting estimates. 相似文献
6.
Introduction to focus issue: mesoscales in complex networks 总被引:1,自引:0,他引:1
7.
Therapeutic drug monitoring of cefepime with micellar electrokinetic capillary chromatography: Assay improvement,quality assurance,and impact on patient drug levels 下载免费PDF全文
Regula Theurillat Jeannine Joneli Ursula Wanzenried Jeannette Schiess Monika Hurni Thomas Weber Parham Sendi Wolfgang Thormann 《Journal of separation science》2016,39(13):2626-2632
The improvement and performance of a micellar electrokinetic capillary chromatography assay for cefepime in human serum and plasma with a 50 μm id fused‐silica capillary elongated from 40 to 60 cm is reported. Sample preparation with dodecylsulfate protein precipitation at pH 4.5, the pH 9.1 separation medium, and the applied voltage were as reported previously [16]. The change resulted in a significant lower current, higher resolution, and increased detection time intervals. The performance of the assay with multilevel internal calibration was assessed with calibration and control samples. Quality assurance data of a 2‐year period assessed under the new conditions demonstrated the robustness of the assay. In serum samples of patients who received both cefepime and sulfamethoxazole, cefepime could not be detected due to the inseparability of the two compounds. The presence of an interference can be recognized by an increased peak width (width > 0.2 min), the appearance of a shoulder or an unresolved double peak. The patient data gathered during a 3‐year period reveal that introduction of therapeutic drug monitoring led to a 50% reduction of the median drug level. The data suggest that therapeutic drug monitoring can help to minimize the risk of major adverse reactions and to increase drug safety on an individual basis. 相似文献
8.
Ammar S Mahjoub MA Charfi N Skandarani I Chekir-Ghedira L Mighri Z 《Chemical & pharmaceutical bulletin》2007,55(3):385-388
A new skeleton of an O-heteroside natural substance named zinolol, the first representative of a new class of aminated hydroxyhydroquinone, has been isolated from the whole plant Anagallis monelli. Its structure has been established by one and two dimensional NMR spectroscopic procedures. Antioxidant, mutagenic, antimutagenic activities were realised and positive results were recorded. 相似文献
9.
Nesrine Zaouadi Benamar Cheknane Abdelkader Hadj-Sadok Jean Paul Canselier 《Journal of Dispersion Science and Technology》2013,34(1):94-102
The main objective of this study is to develop a new formula for a diet mayonnaise-like sauce without cholesterol. Emulsifying power is provided by the use of soy lecithin and the total fat content was limited to 16%. Droplet size measurement of employed mayonnaise samples at different times show that the largest diameter of fat does not exceed 18.5 µm with a yield stress of 56.1 Pa. Results of stability to centrifugation reveal that the absence of the supernatant oily layer ensures the stability of the emulsion. Using the experimental design method, the number of trials can be limited to a number of 16 experiments, and best formulation of the mayonnaise (without cholesterol) was obtained. 相似文献
10.
Samia Rourou Nesrine Riahi Samy Majoul Khaled Trabelsi Héla Kallel 《Applied biochemistry and biotechnology》2013,170(7):1724-1737
Subcultivation of Vero cells grown in a proprietary animal component-free medium named IPT-AFM, on microcarriers, was studied. TrypLE Select, a non-animal-derived protease, was used as an alternative to trypsin for cell passaging. We first studied the effect of increasing concentrations of TrypLE Select toward cell growth and then studied the inactivation of the protease using either soybean trypsin inhibitor (STI) or the soy hydrolysate Hypep 1510, in six-well plates. Data showed that cell growth was impaired by residual level of TrypLE Select; STI was identified as an efficient agent to neutralize this effect. To restore cell growth and inactivate TrypLE Select, STI should be added to the medium at least at 0.2 g L?1. Cells were also grown in spinner flask on 2 g L?1 Cytodex1 in IPT-AFM. In these conditions, the cell detachment yield was equal to 78?±?8 %. Furthermore, cells exhibited a typical growth profile when using the dislodged cells to seed a new culture. A cell detachment yield of 70?±?19 % was also achieved when the cells were grown in a 2-L stirred bioreactor in IPT-AFM, on 3 g L?1 Cytodex1. This protocol can be of great interest to scale-up the process of Vero cells cultivation in IPT-AFM on Cytodex1 from one stirred bioreactor culture to another. 相似文献