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We report a stainless steel/multi walled carbon nanotubes/polyaniline (SLS/MWCNTs/PANI) capacitor electrode capable of operating in a physiological electrolyte and in serum. The specific capacitance of SLS/MWCNTs/PANI reaches 401 F g(-1) in the physiological electrolyte and 326 F g(-1) in serum. The capacity loss at 6.4 μA mm(-2) over 2000 cycles is 10% in the physiological electrolyte and 21% in serum. 相似文献
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BM Kobilka AV Dubrovskiy MD Ewan AL Tomlinson RC Larock S Chaudhary M Jeffries-El 《Chemical communications (Cambridge, England)》2012,48(71):8919-8921
3,7-Diiodo-2,6-di(thiophen-2-yl)benzo[1,2-b:4,5-b']difurans are efficiently prepared by an iodine-promoted double cyclization. This new heterocyclic core is readily modified by the attachment of alkyl chains for improved solubility. The use of these compounds for the synthesis of new conjugated polymers is also reported. 相似文献
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Ash's functions N σ ,k count the number of k ‐equivalence classes of σ ‐structures of size n . Some conditions on their asymptotic behavior imply the long standing spectrum conjecture. We present a new condition which is equivalent to this conjecture and we discriminate some easy and difficult particular cases. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Malika Lahiani-Skiba Yannick Boulet Ibrahima Youm Fréderic Bounoure Philippe Vérité Philippe Arnaud Mohamed Skiba 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):211-217
The aim of the study was to evaluate if the complexation of a hydrophilic molecule by cyclodextrins is possible. Cyclodextrins
(CDs) are hydrophilic cone shaped molecules, which are used as vehicles able to include organic molecules. Because of the
presence of hydroxy groups (OH) outside of the molecule, cyclodextrins are not predisposed to include hydrophilic drugs. They
are therefore used to improve the solubility of poor water-soluble molecules. In order to evaluate if the complexation of
a hydrophilic molecule by cyclodextrins is possible, lyophilized complexes of cysteamine hydrochloride with α-cyclodextrins
(α-CD) have been realized. Six analytical techniques (High performance Liquid Chromatography coupled to UV detection, Thin-Layer
Chromatography, Fourier Transform Infrared spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Mass Spectrometry
(SM) and Proton Nuclear Magnetic Resonance (NMR-NOESY spectra)) were used in order to characterize the interaction between
the drug and the α-CD. The realization of complex between a cyclodextrin and a water-soluble drug seems feasible. In the case
of a hydrophilic molecule, the complexation is not obtained by inclusion of the drug in the cyclodextrin, but by binding to
the outside of the cone. This “external complexation” is however sufficient to improve some features of the molecule, such
as organoleptic features, and to modifiy measurable parameters (FT-IR, DSC, SM and NMR-NOESY spectra). 相似文献
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In this account, [BMIM]6P2Mo18O62 hybrid material was further characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy. XRD illustrated that compared to the parent K6P2Mo18O62·nH2O, where 92 % of the structure is crystalline, 84 % of the structure of [BMIM]6P2Mo18O62 hybrid material is fine-grain amorphous and only 16 % is crystalline. This was attributed to the replacement of most of the protons and constitution water molecules in K6P2Mo18O62·nH2O by [BMIM]+ cations. TEM showed that K6P2Mo18O62·nH2O has uniform and spherical nanoparticles with an average diameter of ~100 nm. However, the hybrid material displayed less uniform morphology with spherical and variously shaped nanoparticles with diameters varying from ~10 to 100 nm. Raman spectroscopy of [BMIM]6P2Mo18O62 illustrated that peaks of the Dawson [P2Mo18O62]6? unit in [BMIM]6P2Mo18O62 hybrid material are not obvious due to the overlap with the peaks of [BMIM]+. The latter was related to the large number of [BMIM]+ cations surrounding the Dawson unit in the hybrid material. [BMIM]6P2Mo18O62 was immobilized on glassy carbon electrode and studied by electrochemistry. Linear sweep voltammetry illustrated that unlike the parent polyoxoanion [P2Mo18O62]6? which showed no particular catalytic activity towards the oxidation of the NADH coenzyme, the hybrid material [BMIM]6P2Mo18O62 is found to efficiently catalyze the oxidation of the NADH coenzyme at low overpotentials. Amperometry revealed high sensitivities (~1.97 μA?mM?1?mm?2) and extended linearity (~9.1 mM) of [BMIM]6P2Mo18O62/GC electrode towards the oxidation of the NADH coenzyme. 相似文献
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Sihem Hessainia Malika Berredjem Souad Ouarna Zinelaabidine Cheraiet Nour-Eddine Aouf 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):719-725
Abstract The synthesis of two new series of functionalized phosphonates is described. A new entry for the synthesis of 5-phosphonoalkyl cyclosulfamides and bis(phosphonoalkyl) sulfamides starting from dihalogeno bis(amino) sulfone has been developed. These compounds have been synthesized in good yields. Triethylphosphite has been used to introduce the phosphonate moiety into sulfamides and cyclosulfamides via Arbuzov reaction. 相似文献
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The effect of Sodium tripolyphosphate (STPP) and mineral additive on the performance of the lead-acid battery positive plate has been investigated. The addition of alumina-silicate to the positive paste and STPP to the electrolyte modifies the shape and size of PbO2 crystals and improves the utilization of the positive active material (PAM). The electrochemical performance of the positive active material was determined using galvanostatic discharge and electrochemical impedance spectroscopy (EIS). The crystal structure and morphology of the PAM (PbO2) were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The water content of the PAM was calculated using Thermogravimetric analysis (TGA) technique. The results showed that the addition of surfactant and mineral additive changes the morphology and the crystallite size of the PAM. We observe a remarkable improvement of the discharge capacity of the PAM when the surfactant (STPP) is added in the electrolyte. The discharge capacity increases with the decrease of the crystallite size and the charge transfer resistance Rct of the PAM. This shows that the addition of mineral additive and the surfactant together improves the electrical performance of lead-acid battery. 相似文献
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We wish to report here a new and efficient partial synthesis of 3-oxa-5β-steroid, the first oxa steroid synthesized from cholic acid. 相似文献
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Jallal Zoubir Chaimae Radaa Nadia Bougdour Abderrahim Idlahcen Widad El Hayaoui Naoual Tajat Wail El Mouhri Iliass Nadif Samir Qourzal Malika Tamimi Ali Assabbane Idriss Bakas 《印度化学会志》2022,99(8):100590
Nitrofurazone is a nitrofuran-family synthetic chemical that has been used to treat bacterial infections since 1993. Silver nanoparticles synthesized by the thermal technique on graphite carbon sheets under optimal conditions were used to develop a highly sensitive electrochemical sensor. The main experimental characteristics are optimized to assure that this sensor functions correctly. Scanning electron microscope, X-ray diffraction, infrared spectroscopy were used to determine the chemical composition and morphology of the prepared pastes. With a maximal reduction peak of La nitrofurazone observed at ?0.57V/Ag-NPs@CPE versus Ag/AgCl, this sensor demonstrated good electrocatalytic activity for the reduction of La nitrofurazone. The influence of phosphate buffer solution pH indicates that the numbers of protons and electrons in the reaction at the surface of our constructed sensor were the same. The LOD and LOQ were calculated to be 1.2 × 10?8 M and 1.3 × 10?7 M, respectively. Using the differential pulse voltammetry technique, the calibration curve was established in the concentration range of 10?4 M to 2 × 10?7 M. Our Ag-NPs@CPE sensors were evaluated in order to detect nitrofurazone in real contaminated samples tap water, commercial milk, and human urine, in particular. The electroanalysis results show a very high recovery rate of more than 96% on average, permitting us to determine that our sensors are functional under optimum working conditions. 相似文献