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Electrochemical methods can be applied in a number of ways as detection systems for competitive immunoassays, especially through the use of redox-labelled antigens. To overcome the problem of detection of such conjugates at low concentration, a system is described in which a poly(vinylferrocene)-modified glassy carbon electrode is used to accumulate charge from solution glucose/glucose oxidase via the intermediacy of a redox-labelled antigen, cycled repeatedly between the enzyme and the electrode. The charge accumulated by the electrode is measured electrochemically by returning the electrode to its original potential and integrating the resulting current-time transient. The charge is proportional to the concentration of redox-labelled antigen in solution and to the charge-accumulation time. In this way 1,1'-dimethylferrocene-ethan-1-ol-2-amine was reproducibly detected to 0.9 nM, with a 10 min incubation period. The 8-ferrocenyl conjugate of theophylline was characterised as a model system for possible application in a higher sensitivity electrochemical immunoassay. 相似文献
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Deutero-alcohol (2b) was prepared and dehydrated with H2SO4Ac2OHOAc to give a kinetic isotope effect demonstrating anion mobility within the intermediate carbocation-anion ion pair. 相似文献
55.
H. Gr?ssler D. Lanske R. Schulte G.T. Jones R.P. Middleton S.W. ONeale K. B?ckmann W. Gebel C. Geich-Gimbel B. Nellen A. Grant H. Klein D.R.O. Morrison P. Schmid H. Wachsmuth J.S. Chima M.M. Mobayyen J. Wells 《Nuclear Physics B》1983,223(2):269-295
In an experiment with the hydrogen bubble chamber BEBC at CERN multiplicities of hadrons produced in νp and interactions have been investigated. Results are presented on the multiplicities of charged hadrons and neutral pions, forward and backward multiplicities of charged hadrons and correlations between forward and backward multiplicities. Comparisons are made with hadronic reactions and e+e? annihilation. In the framework of the quark-parton model the data imply similar charged multiplicities for the fragments of a u- and a d-quark, and a larger multiplicities for the fragments of a uu- than for a ud-diquark. The correlation data suggest independent fragmentation of the quark and diquark for hadronic masses above ~ 7 GeV and local charge compensation within an event. 相似文献
56.
G. T. Jones B. W. Kennedy R. P. Middleton S. W. O'Neale A. M. Cooper A. Grant H. Klein J. Mittendorfer D. R. O. Morrison A. Parker P. Schmid H. Wachsmuth F. Hamisi M. M. Mobayyen O. Villalobos-Baillie M. Aderholz L. Deck N. Schmitz W. Wittek G. Corrigan G. Myatt D. Radojicic M. Retter 《Zeitschrift fur Physik C Particles and Fields》1984,25(2):121-127
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible. 相似文献
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S. Mordechai H.T. Fortune G.E. Moore M.E. Cobern R.V. Kollarits R. Middleton 《Nuclear Physics A》1978,301(3):463-476
The reaction 12C(t, p)14C has been investigated with an 18 MeV triton beam. Twenty energy levels of 14C were identified up to 13 MeV excitation. Angular distributions were measured and compared with DWBA calculations. A previously unreported 0+ level at 9.75 MeV was observed; it undoubtedly corresponds to the second predominantly sd shell 0+ state in 14C. Additional spin and parity assignments have been made in the present work: 9.81 MeV, (1?); 10.43 MeV, 2+; 10.50 MeV, (3?); 10.74 MeV, 4+; 11.40 MeV, 1?; 11.67 MeV, (1?); 11.73 MeV, (5?); 12.58 MeV, (2+, 3?); 12.87 MeV. 2+, 3?; and 12.96 MeV, (1?); none of which had a definite spin and parity assignment previously. Our results confirm the previous information on the level structure of 14C below 8.5 MeV. The cross section for the unnatural parity state at 7.34 MeV, Jπ = 2?, is well reproduced by a two-step reaction calculation. The results are compared with the predictions of a weak coupling model. 相似文献
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The reaction 14N(3He, p)16O has been investigated at a bombarding energy of 15.0 MeV, using a differentially pumped gas target. Angular distributions were measured for 30 levels below 16.5 MeV in excitation. Data were compared with shell-model calculations of Zuker, Buck and McGrory for states whose correspondence with theory is established. Many states are found to possess a large compound-nucleus reaction component. Several previously unreported levels are observed at high excitation. Angular distributions for all except the weakest levels have been compared with DWBA calculations. 相似文献