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141.
The first example of using an edge plane pyrolytic graphite electrode in electroanalysis is reported as the determination of homocysteine, N-acetylcysteine, cysteine and glutathione is studied. The response of the electrode in the direct oxidation of thiol moieties is explored and found to be electrocatalytic producing a reduction in the overpotential while having enhanced signal-to-noise characteristics compared to glassy carbon and basal plane pyrolytic graphite electrodes. The effectiveness of the methodology is examined in the determination of cysteine species in a growth tissue media that contains a high number of common biological interferences. The advantageous properties of this electrode for thiol determination lie in its excellent catalytic activity, sensitivity and simplicity. 相似文献
142.
Cathryn E Langley Biljana Sljuki? Craig E Banks Richard G Compton 《Analytical sciences》2007,23(2):165-170
The modification of carbon powder with manganese dioxide using a wet impregnation procedure with electrochemical characterisation of the modified powder is described. The process involves saturation of the carbon powder with manganese(II) nitrate followed by thermal treatment at ca. 773 K leading to formation of manganese(IV) oxide on the surface of the carbon powder. The construction of composite electrodes based on manganese dioxide modified carbon powder and epoxy resin is also described, including optimisation of the percentage of the modified carbon powder. Composite electrodes showed attractive performances for electroanalytical applications, proving to be suitable for the electrochemical detection of hydrogen peroxide, ascorbic acid and nitrite ions with limits of detection comparable to the detection limits achieved by other analytical techniques. The results obtained for detection of these analytes, together with composite electrodes flexible design and low cost offers potential application of composite electrodes in biosensors. 相似文献
143.
The azimuthal dependence of third-order and cascaded second-order nonlinear coupling was used to measure the relative contributions of each to direct third-harmonic generation in beta-barium borate. This permitted the measurement of the values of tensor elements chi(3)(10) , chi(3)(11) , and chi(3)(16) relative to the known chi(2)(ij) . Finally, conversion efficiencies to 3 omega of up to 6% were achieved with a femtosecond chirped-pulse amplification laser with 200 GW/cm(2) in collimated beams. 相似文献
144.
An RSA modulus is a product M=pl of two primes p and l. We show that for almost all RSA moduli M, the number of sparse exponents e (which allow for fast RSA encryption) with the property that gcd(e,?(M))=1 (hence RSA decryption can also be performed) is very close to the expected value. 相似文献
145.
Ronald E. Banks J.Michael Birchall Robert N. Haszeldine William J. Nicholson 《Journal of fluorine chemistry》1982,20(1):133-134
Perfluoroallyl fluorosulphonate, procured treatment of perfluoropropene with stabilized sulphur trioxide (‘Sulfan’), reacts with potassium iodide, potassium bromide, sodium methoxide, and phenylmagnesium bromide to yield the corresponding perfluoroallyl derivatives CF2CFCF2X, where X = I, Br, OMe, and Ph respectively. 相似文献
146.
William R. Banks Amale A. Hawi George A. Digenis 《Journal of heterocyclic chemistry》1991,28(2):533-535
The addition of 7-chloro-2-hydrazono-5-phenyl-1,2-dihydro-3H-1,4-benzodiazepine 3 to a mixture of sodium acetate and 1,1′-carbonyldiimidazole 1 at room temperature gave, in moderate yields, carbonyl-1,1′-bis[7-chloro-5-phenyl-1,2-dihydro-3H-1,4-benzodiazepin-2-ylidene hydrazone] 7 instead of the expected 2-acetylhydrazono-7-chloro-5-phenyl-1,2-dihydro-3H-1,4-benzodiazepine 4 . 相似文献
147.
Three different electroanalytical techniques for the determination of zinc in blood are investigated. The direct determination in diluted blood via anodic stripping voltammetry at glassy carbon and the use of Nafion-coated glassy carbon mercury electrodes are shown to lack the necessary sensitivity whereas an acoustically assisted double extraction followed by sono-ASV using a glassy carbon electrode is found to be rapid, reliable and sensitive. 相似文献
148.
The thallium-indium alloys were dissolved in sulphuric acid (1 + 1). In this medium thallium remained in the univalent state and could be determined directly, without a separation, by an oxidation-reduction titration with potassium bromate. The indium was determined directly with an EDTA titration. Ascorbic acid was added to maintain the thallium in the univalent state, which did not interfere. Ascorbic acid also masked any interfering tervalent thallium by effectively reducing it to the univalent state. Sharp end-points were obtained for both titrations, which were carried out in the temperature range of 50-95 degrees . The method offers excellent precision and accuracy. 相似文献
149.
K.S. Kaur M. FeinaeugleD.P. Banks J.Y. OuF. Di Pietrantonio E. VeronaC.L. Sones R.W. Eason 《Applied Surface Science》2011,257(15):6650-6653
In this paper we report femtosecond laser-induced forward transfer (LIFT) of pre-machined donor films. 1 μm thick zinc oxide (ZnO) films were first machined using the focussed ion beam (FIB) technique up to a depth of 0.8 μm. Debris-free micro-pellets of ZnO with extremely smooth edges and surface uniformity were subsequently printed from these pre-machined donors using LIFT. Printing results of non-machined ZnO donor films and films deposited on top of a polymer dynamic release layer (DRL) are also presented for comparison, indicating the superior quality of transfer achievable and utility of this pre-machining technique. 相似文献
150.
H.B. Banks W. Bi L. Sun G.F. Chen X.H. Chen J.S. Schilling 《Physica C: Superconductivity and its Applications》2011,471(15-16):476-479
The ac susceptibility of single crystalline tetragonal EuFe2As2, EuFe2As1.4P0.6, and EuFe1.715Co0.285As2 has been measured over the temperature and hydrostatic (He-gas) pressure ranges 10–60 K and 0–0.8 GPa, respectively. For all three samples the magnetic ordering temperature (17–19 K) from the Eu sublattice increases linearly with pressure, presumably due to the enhanced exchange coupling between Eu-layers. No evidence for a superconducting transition was observed in the susceptibility for any sample over the measured temperature/pressure range. 相似文献