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1.
Fatima Hassine Said Gmouh Mathieu Pucheault Michel Vaultier 《Monatshefte für Chemie / Chemical Monthly》2007,57(12):1167-1174
In this work was presented an application of the use of task specific onium salts (TSOSs) as soluble supports in Grieco’s multicomponent synthesis of tetrahydroquinolines. These soluble supports are of wide applicability and combine advantages
of solid phase synthesis without its limitations with those of solution phase chemistry. After a simple washing step, products
were cleaved from the supports and obtained in pure form and good yields. 相似文献
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The interfering effects of various foreign ions on the determination of arsenic were studied by hydride generation inductively coupled plasma atomic emission spectrometry (HG-ICP-AES). There were serious inhibiting interferences by Cu, Pb, Co, Au, Pd and Ni. However, by using cyanide as a complexing agent these interferences could be completely eliminated over a wide range of interferent concentration. The optimum chemical parameters for continuous arsine generation were studied. A major advantage of this technique is that it only needs low acid concentrations and produces less hazardous waste. Sensivity, selectivity and accuracy of the determination of arsenic by HG-ICP-AES were investigated. The detection limit (in 1 mol/l HCl medium) for arsenic(III) was 0.82 ng/ml. The relative standard deviation for ten determinations of a solution containing 50 ng/ml arsenic was 1.3%. 相似文献
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A convenient and efficient reductive amination for the preparation of chiral β-amino amides is developed utilizing microwave heating. A variety of chiral β-keto amides react with ammonium acetate and sodium cyanoborohydride to afford the desired functionalized amines in good yields. This improved procedure takes advantage of microwave heating to significantly accelerate the reaction and offers a convenient and effective method to access some interesting molecules containing primary amine functionalities. 相似文献
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Amel Souibgui Anne Gaucher Jérôme Marrot Flavien Bourdreux Faouzi Aloui Béchir Ben Hassine Damien Prim 《Tetrahedron》2014
New series of acridines and phenanthrolines have been prepared from β-chlorovinyl aldehydes and various aniline derivatives allowing the installation of valuable substituents, such as ketone, nitro or amino groups at the heterocyclic core. X-ray analyses confirmed the structures of acridines and phenanthrolines as well as the presence of partially hydrogenated rings and their crucial impact on the overall shape of the acridine-based architectures. 1H NMR revealed the helical behaviour of several acridine motives. Comparison of UV data between architectures and influence of number of partially hydrogenated rings is also described. 相似文献
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Alejandro Valverde Amira ben Hassine Vernica Serafín Cristina Muoz‐San Martín María Pedrero María Garranzo‐Asensio Maria Gamella Noureddine Raouafi Rodrigo Barderas Paloma Yez‐Sedeo Susana Campuzano Jos M. Pingarrn 《Electroanalysis》2020,32(4):706-714
This paper reports the development of a dual immunosensor using magnetic microcarriers (MBs) and amperometric transduction at dual screen‐printed carbon electrodes (SPdCEs) for the simultaneous determination of two biomarkers: interleukin‐13 receptor α2 (IL‐13Rα2) and E‐cadherin (E‐CDH), with both extracellular and soluble fraction; oncogenic and tumor suppressor markers, respectively, of great relevance in metastatic processes. The implemented methodology involved the formation of sandwich‐type immunocomplexes using specific capture antibodies immobilized onto carboxylic acid magnetic microbeads (HOOC‐MBs), and biotinylated detector antibodies labeled with streptavidin?horseradish peroxidase conjugates (Strep‐HRP). The amperometric detection was performed by addition of hydrogen peroxide in the presence of hydroquinone (HQ) as the redox mediator. The dual immunosensing platform provided linear calibration ranges suitable for the determination of both biomarkers in liquid and solid clinical specimens as well as excellent selectivity against other cancer biomarkers. This simple handling dual bioplatform was applied to the determination of the soluble and extracellular fraction of the target biomarkers in serum and paraffined‐embedded tissues from colorectal cancer (CRC) patients diagnosed at different tumor grade. The obtained results reveal great potential of this configuration to improve the reliability in diagnosing metastatic CRC. 相似文献
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Electrochemical Capacitive K+ EMIS Chemical Sensor Based on the Dibromoaza[7]helicene as an Ionophore for Potassium Ions Detection
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Moncef Tounsi Mourad Ben Braiek Abdoullatif Baraket Michael Lee Nadia Zine Miguel Zabala Joan Bausells Faouzi Aloui Béchir Ben Hassine Abderrazak Maaref Abdelhamid Errachid 《Electroanalysis》2016,28(12):2892-2899
A K+‐sensitive capacitive electrolyte‐membrane‐insulator‐semiconductor (EMIS) based on a novel dibromoaza[7]helicene ionophore has been developed. An ion‐sensitive membrane based on polyvinylchloride (PVC) doped with the ionophore was deposited on the Si3N4/SiO2/Si‐p/Cu‐Al transducer. The properties of the K+‐EMIS chemical sensor were investigated by electrochemical impedance spectroscopy (EIS). All the developed devices upon being tested have shown good sensitivity and linearity responses within the range 10?6 M to 10?1 M of potassium activity, with good selectivity over a wide variety of other cations (Na+, Li+, Cu2+, Ca2+, and Mg2+). To our knowledge, this is the first time that a capacitive field‐effect sensor has been fabricated using helicene as a carrier for K+‐detection, combined with the structure: Si3N4/SiO2/Si‐p/Cu‐Al as a transducer. 相似文献
9.
Mourad Hrizi Maatoug Hassine Mohamed Abdelwahed Nejmeddine Chorfi 《Mathematical Methods in the Applied Sciences》2019,42(18):6083-6100
The aim of this work is to reconstruct the location and geometry of a cavity embedded in a linear isotropic material Ω via an exterior boundary measurement of the displacement field. The considered problem is governed by the linear elasticity system. This inverse problem of geometry reconstruction (ie, location and shape) is formulated as a topology optimization one and solved by minimizing a Kohn‐Vogelius type functional with the help of the topological sensitivity method. Some numerical results are presented using a noniterative geometric algorithm. 相似文献
10.
We study the effects of the semiconductor laser noise on the generated beat signal, in Coherent Optical Domain Reflectometry device. By using a general laser noise analytical model, based on Volterra non-linear treatment of laser rate equations, we find a novel general expression of the beat photocurrent. We show that the coherence and the incoherence cases are observed for a different delay time intervals than the ones known in literature. We show that the coherence domain corresponds to a delay time lower than the half of the laser coherence time τ0<1/2τc, and the incoherence domain corresponds for τ0>2τc. An original shape of the beat signal autocorrelation function affected by the laser noises is obtained. 相似文献