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Eissa  Shimaa  Zourob  Mohammed 《Mikrochimica acta》2017,184(7):2281-2289
Microchimica Acta - The authors describe a voltammetric immunosensor for morphine (MOR) that is based on a graphene screen printed electrode (GSPE) modified with gold nanoparticles (AuNP) which...  相似文献   
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The template condensation of acetoacetic-2-pyridylamide with amino aliphatic alcohols such as 2-aminoethanol (HL1) and 3-amino propanol (HL2) in the presence of copper(II) ions gave octahedral complexes, which have been characterized by elemental analyses, u.v.-vis. and i.r. spectra, conductivity, d.t.a, magnetic and e.s.r. measurements. The molar conductance in DMF indicate that the complexes are non-ionic in character. The e.s.r. spectra of solid complexes (2) and (5) at room temperature indicate axial type symmetry (dx2-y2) with covalent bond character.  相似文献   
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A novel temperature responsive water-soluble glycopolymer was synthesised via copper wire-catalysed click-polymerisation. Di-hydroxyl terminated poly(ethylene glycol) was quantitatively alkyne end-capped to yield di-alkyne terminated poly(ethylene glycol) (DAT-PEG). 2,3,4,2′,3′,4′-hexa-O-acetyl-6,6′-diazido-6,6′-dideoxy-α,α-D-trehalose (HADADT) was prepared from the di hydrated α,α-D-Trehalose by tosylation/acetylation followed by azidation. Click-polymerisation reaction between DAT-PEG and HADADT was successfully carried out to produce an alternating glycopolymer with triazole rings as linkers in high yield. All the intermediates as well as the glycopolymer were fully characterised by NMR, MS, IR, SEC, TGA and DSC. The cloud point of the aqueous solution of glycopolymer was investigated by optical microscopy and UV–vis spectroscopy. The LCST was found to be within physiological range of about 39 °C, known as fever temperature.  相似文献   
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The response of a homeotropically aligned columnar phasmidic liquid crystal (CPLC) to rectilinear oscillatory shear was investigated for frequencies between 10-2 and 100 Hz and cell thicknesses between 20 and 100 μm. At threshold shear amplitude, we observed a spatial pattern consisting of stationary bands, perpendicular to the direction of shear and localized in the bulk of the columnar sample. For fixed thickness and at threshold shear amplitude, we observed band structure for several frequencies corresponding to integer harmonics νo, 2νo, 3νo. We interpret the obtained results in terms of curvature walls that evolve gradually, according to the amplitude, to characteristic developable domain walls of the columnar phase.  相似文献   
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We have previously shown, by redundant Klee–Minty constructions, that the central path may arbitrarily closely visit every vertex of the Klee–Minty cube. In those constructions, the redundant constraints are far away from the feasible region. In this paper, we provide a construction in which all redundant constraints touch the feasible region.  相似文献   
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The unsteady magnetohydrodynamic flow of an electrically conducting viscous incompressible non-Newtonian Bingham fluid bounded by two parallel non-conducting porous plates is studied with heat transfer considering the Hall effect. An external uniform magnetic field is applied perpendicular to the plates and the fluid motion is subjected to a uniform suction and injection. The lower plate is stationary and the upper plate moves with a constant velocity and the two plates are kept at different but constant temperatures. Numerical solutions are obtained for the governing momentum and energy equations taking the Joule and viscous dissipations into consideration. The effect of the Hall term, the parameter describing the non-Newtonian behavior, and the velocity of suction and injection on both the velocity and temperature distributions are studied.  相似文献   
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Electrochemical oxidation of indapamide has been investigated at glassy carbon electrode using cyclic and differential pulse voltammetry (DPV). Indapamide exhibited two well resolved signals which attributed to the oxidation of indoline ring and benzamide moiety in phosphate buffers in the pH range of 2.7?C10.1. The oxidation processes have been shown to be irreversible and diffusion controlled. The formation of an inclusion complex of indapamide with ??-cyclodextrin (??-CD) has been investigated by cyclic, differential pulse voltammetry as well as UV?CVis spectrophotometry. The stability constant of the complex was determined to be 6199 and 2717 M?1 using differential pulse voltammetry and UV?CVis spectrophotometry, respectively.  相似文献   
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β‐(4‐Chlorobenzoyl)acrylic acid (1) proved to be a convenient precursor for the synthesis of a variety of heterocyclic systems through the reaction with compounds containing active methylene groups under Michael reaction conditions. Also, the reactivity of Michael adduct towards nitrogen nucleophiles was investigated to afford diazepine, indazole, isoxazole and quinazoline derivatives. Some of the synthesized compounds were screened for their biological activity.  相似文献   
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