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1.
Using preilluminating flashes at 2°C prior to continuous excitation of isolated chloroplasts at -80°C, a period-four oscillation with maxima at the 0th, 4th and 8th flashes was observed in the amplitude of the thermoluminescence band Zv. Inactivation of the water-splitting system by hydroxylamine- or Tris-treatments greatly diminished the Zv band. On the other hand, its amplitude was not considerably affected by the addition of inhibitory concentration of DCMU. On the basis of the results, the possible origin of the Zv band is discussed.  相似文献   
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Let be a path of bounded operators on a real Hilbert space, hyperbolic at . We study the Fredholm theory of the operator . We relate the Fredholm property of to the stable and unstable linear spaces of the associated system . Several examples are included to point out the differences with respect to the finite dimensional case, in particular concerning the role of the spectral flow. We define a general class of paths A for which many properties typical of the finite dimensional framework still hold. Our motivation is to develop the linear theory which is necessary for the set-up of Morse homology on Hilbert manifolds. Received: 9 March 2001; in final form: 1 March 2002 / Published online: 2 December 2002  相似文献   
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Majer JR 《Talanta》1972,19(5):589-621
A review is made of the basic theory, instrumentation and application of mass spectrometry, with special reference to the development of the equipment and its impact on the scope of application.  相似文献   
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Application of the microwave (MW) technique offers many advantages in organophosphorus syntheses. Reluctant reactions may take place on MW irradiation. In most cases, MWs make the reactions more efficient in respect of rate, selectivity and yield. The benefits are shown via representative examples. MW irradiation may replace a catalyst, or simplify catalytic systems. The synthesis of catalysts incorporating heterocyclic P-ligands is also discussed. Where it was relevant, structural chemical details were also provided.  相似文献   
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Preparative details for perfluoroalkanoylpivalylmethanes and their lead chelates are given. Thermal analysis, gas chromatography and mass spectral studies all indicate high thermal stability, but strong column interaction makes successful quantitative gas chromatography difficult. The integrated ion-current technique is applied to determine lead heptafluorobutanoylpivalylmethanate in the range 10-9–10-7 g of lead, but a lower detection limit of ca. 10-14 g is indicated.  相似文献   
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The isomerization of benzophenone oxime to benzanilide, previously observed to take place in the ion source of a mass spectrometer and attributed to a Beckmann type rearrangement of the benzophenone oxime molecule ion, has been shown to occur by a thermal mechanism prior to ionization. Mass spectrometric evidence is supplemented by infrared spectrophotometric examination of solid samples and shows that in the solid state, at room temperature, benzophenone oxime has a lifetime of about 600 h.  相似文献   
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