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101.
102.
Kevin J. Compton 《Archive for Mathematical Logic》1985,25(1):91-98
An extension of a Tauberian theorem of Hardy and Littlewood is proved. It is used to show that, for classes of finite models satisfying certain combinatorial and growth properties, Cesàro probabilities (limits of average probabilities over second order sentences) exist. Examples of such classes include the class of unary functions and the class of partial unary functions. It is conjectured that the result holds for the usual notion of asymptotic probability as well as Cesàro probability. Evidence in support of the conjecture is presented. 相似文献
103.
104.
Singlet Oxygen and the Origin of Oxygen Functionalities on the Surface of Carbon Electrodes
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Korbua Chaisiwamongkhol Dr. Christopher Batchelor‐McAuley Dr. Robert G. Palgrave Prof. Dr. Richard G. Compton 《Angewandte Chemie (International ed. in English)》2018,57(21):6270-6273
The generation of oxygen‐containing functionalities on pristine carbon surfaces is investigated and shown to be light sensitive, specifically to infra‐red radiation. A mechanistic route involving singlet oxygen, 1O2, is proposed and evidenced. 相似文献
105.
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106.
Electrocatalysis at graphite and carbon nanotube modified electrodes: edge-plane sites and tube ends are the reactive sites 总被引:3,自引:0,他引:3
Banks CE Davies TJ Wildgoose GG Compton RG 《Chemical communications (Cambridge, England)》2005,(7):829-841
Carbon, and particularly graphite in its various forms, is an attractive electrode material. Two areas of particular interest are modified carbon electrodes and carbon nanotube electrodes. In this article we focus on the relationship between surface structure and electrochemical and chemical reactivity of electrodes based on these materials. We overview recent work in this area which has led us to believe that much of the catalytic activity, electron transfer and chemical reactivity of graphitic carbon electrodes is at surface defect sites, and in particular edge-plane-like defect sites. We also question the claimed special "catalytic" properties of carbon nanotube modified electrodes. 相似文献
107.
The liquid chromatographic retention behavior of triglyceride and phospholipid molecular species in the nonpolar stationary (reverse) phase mode is presented for mobile phases compatible with ultraviolet detection. Interpretation of the results by means of the Kovats retention index suggests that correlation of retention to structure requires information on the number of acyl double bonds contained within the lipid molecular species in question. This, in turn, indicates that detection plays a major role in elucidating lipid structure because insufficient information is contained in the chromatographic retention data. 相似文献
108.
Microwave activation of electrochemical processes: enhanced electrodehalogenation in organic solvent media 总被引:2,自引:0,他引:2
Tsai YC Coles BA Compton RG Marken F 《Journal of the American Chemical Society》2002,124(33):9784-9788
The effect of high-intensity microwave radiation focused into a "hot spot" region in the vicinity of an electrode on electrochemical processes with and without coupled chemical reaction steps has been investigated in organic solvent media. First, the electrochemically reversible oxidation of ferrocene in acetonitrile and DMF is shown to be affected by microwave-induced thermal activation, resulting in increased currents and voltammetric wave shape effects. A FIDAP simulation investigation allows quantitative insight into the temperature distribution and concentration gradients at the electrode / solution interface. Next, the effect of intense microwave radiation on electroorganic reactions is considered for the case of ECE processes. Experimental data for the reduction of p-bromonitrobenzene, o-bromonitrobenzene, and m-iodonitrobenzene in DMF and acetonitrile are analyzed in terms of an electron transfer (E), followed by a chemical dehalogenation step (C), and finally followed by another electron-transfer step (E). The presence of the "hot spot" in the solution phase favors processes with high activation barriers. 相似文献
109.
The quality of sample preparation is a key factor in determining the success of analysis. While analysis of pharmaceutically important compounds in biological matrixes has driven forward the development of sample clean-up procedures in last 20 years, today's chemists face an additional challenge: sample preparation and analysis of complex biochemical samples for characterization of genotypic or phenotypic information contained in DNA and proteins. This review focuses on various sample pretreatment methods designed to meet the requirements for the analysis of biopolymers and small drugs in complex matrices. We discuss the advances in development of solid-phase extraction (SPE) sorbents, on-line SPE, membrane-based sample preparation, and sample clean-up of biopolymers prior to their analysis by mass spectrometry. 相似文献
110.
Alexander Goodwin Craig E. Banks Dario Omanovi? Richard G. Compton 《Analytica chimica acta》2005,533(2):141-145
Cathodic stripping voltammetry at a boron-doped diamond electrode utilising an insonated accumulation protocol is shown to be possible for the on-site trace detection of free manganese in seawater samples. No sample pre-treatment is required with the application of ultrasound providing a sensitive and selective protocol for the analysis of manganese. The protocol is used in the evaluation of manganese in seawater samples taken near the site of a former ferromanganese factory in the town Šibenik, Croatia. 相似文献