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51.
In this study, a series of twelve ring-substituted salicylanilides and carbamoylphenylcarbamates were prepared and characterized. The compounds were analyzed using RP-HPLC to determine lipophilicity. They were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Moreover, their site of action in the photosynthetic apparatus was determined. Primary in vitro screening of the synthesized compounds was also performed against mycobacterial, bacterial and fungal strains. Several compounds showed biological activity comparable with or higher than the standards 3-(3,4-dichlorophenyl)-1,1-dimethylurea, isoniazid, penicillin G, ciprofloxacin or fluconazole. The most active compounds showed minimal anti-proliferative activity against human cells in culture, indicating they would have low cytotoxicity. For all compounds, the relationships between lipophilicity and the chemical structure are discussed.  相似文献   
52.
The process with a distinctive “photon-plus-missing-energy” signal can serve as an important tool to search for new physics at LEP2. It can be exploited to measure the WWγ coupling, or to search for weakly interacting and invisible (s)particles. For meaningful comparisons of experimental data with theoretical predictions, higher-order QED corrections due to multiphoton emission must be taken into account. In the present paper we explain how the WWγ coupling has been incorporated into the KORALZ Monte Carlo program, which can now be used for simulations of events with higher-order QED corrections. The strategy of how to perform an experimental analysis in the presence of experimental cuts is proposed. The question of systematic uncertainties is addressed and some numerical results for the phenomenologically interesting case of anomalous WWγ couplings are also given.  相似文献   
53.
The equilibrium of the formation of N1-(9-fluorenylidene)-ethylenediamine from fluorenone and ethylenediamine has been studied in acetonitrile at 25°C using a polarographic method. The equilibrium constantK for this reaction has been found to depend on the nature of supporting electrolyte cation; the reactivity increases with a decrease of the crystallographic cation radius. The enhanced reactivity is attributed to the hydration of a cation by H2O molecules lost in the reaction. A plot of logK versus the free hydration enthalpy of a cation gives a fairly straight line.
Bildungsgleichgewichte von N1-(9-Fluorenyliden)-ethylendiamin aus Fluorenon und Ethylendiamin in Acetonitril. Der Effekt von Alkalimetall-Kationen
Zusammenfassung Das Gleichgewicht der Bildung von N1-(9-Fluorenyliden)-ethylendiamin aus Fluorenon und Ethylendiamin in Acetonitril bei 25°C wurde mittels einer polarographischen Methode untersucht. Es wurde festgestellt, daß die GleichgewichtskonstanteK dieser Reaktion von der Natur des Elektrolyt-Kations abhängt: die Reaktivität steigt mit abnehmendem kristallographischen Radius der Kationen an. Die erhöhte Reaktivität wird der Hydratation der Kationen mit Wassermolekü len, die bei der Reaktion freigesetzt werden, zugeschrieben. Die graphische Darstellung von logK gegen die freien Hydratationsenthalpien der Kationen ergibt eine Gerade von zureichender Korrelation.
  相似文献   
54.
Summary The essential oil of curry leaves contains numerous terpene and sesquiterpene hydrocarbons as well as polar compounds from which decahydrotetramethylcyclopropazulenol, selin-11-en-4-ol and caryophyllene expoxide have been isolated and identified for the first time. This has been done with the aid both of known classical methods and of modern NMR spectroscopic techniques, such as homo- and heteronuclear COSY, COSY spectra for long-range coupling and inverse TOCSY spectra. The results are summarized and discussed.  相似文献   
55.
The recombination radiation from organic solids, defined as the light emission following the fusion of oppositely charged carriers into an electrically neutral state, is discussed as a phenomenon underlying the function of organic light-emitting diodes (LEDs). Its intensity and spectral range depend on the population and nature of the emissive states, which differ, in general, from those created using light. These differences are pointed out and shown to be a result of the reverse pathways of the mutual transformation of localized molecular excitons and coulombically-correlated charge-pair excited states formed either by photoexcitation or electron-hole recombination. Spectral features of the radiation produced by the recombination of statistically independent charge carriers are discussed in terms of two molecules-based excited states like excimers or electromers in single-component materials and exciplexes or electroplexes in multicomponent materials. Consequences for optical and electrical characteristics of organic LEDs are discussed and illustrated by examples. Progress in the fundamental and applied research may be expected based on properties of recombination-produced electronic excited states.  相似文献   
56.
57.
In the paper we construct the nonsymmetric Jordan-Thiry theory unifying Moffat's theory of gravitation, the Yang-Mills' field, the Higgs' fields and scalar forces in a geometric manner. We discuss spontaneous symmetry breaking, the Higgs' mechanism and mass generation in the theory. The scalar field Ψ (as in classical Jordan-Thiry theory) is connected to the effective gravitational constant. This field is massive and has Yukawa-type behavior. We discuss the relation between R+ invariance and U(1)F from G. U. T. within Einstein λ-transformation, and fermion number conservation. In this way we connect W μ-field from nonsymmetric theory of gravitation with a gauge field A from G. U. T. We derive the equation of motion for a test particle from conservation laws in the hydrodynamic limit.  相似文献   
58.
Zeitschrift für Physik C Particles and Fields - A comprehensive analysis of deep inelastic scattering of polarized charged leptons on polarized nucleons is presented; weak interaction...  相似文献   
59.
The search for MSSM Higgs bosons will be an important goal at the LHC. We analyze the search reach of the CMS experiment for the heavy neutral MSSM Higgs bosons with an integrated luminosity of 30 or 60 fb-1. This is done by combining the latest results for the CMS experimental sensitivities based on full simulation studies with state-of-the-art theoretical predictions of the MSSM Higgs-boson properties. The results are interpreted in MSSM benchmark scenarios in terms of the parameters tan β and the Higgs-boson mass scale, MA. We study the dependence of the 5σ discovery contours in the MA–tan β plane on variations of the other supersymmetric parameters. The largest effects arise from a change in the higgsino mass parameter μ, which enters both via higher-order radiative corrections and via the kinematics of Higgs decays into supersymmetric particles. While the variation of μ can shift the prospective discovery reach (and correspondingly the ”LHC wedge” region) by about Δtan β=10, we find that the discovery reach is rather stable with respect to the impact of other supersymmetric parameters. Within the discovery region we analyze the accuracy with which the masses of the heavy neutral Higgs bosons can be determined. We find that an accuracy of 1–4% should be achievable, which could make it possible in favorable regions of the MSSM parameter space to experimentally resolve the signals of the two heavy MSSM Higgs bosons at the LHC.  相似文献   
60.
The authors implemented a tunable linear cavity Erbium-doped fiber (EDF) laser for the interrogation of multiplexed fiber Bragg grating sensors (BGS). A high-strength single-pulse draw-tower fiber Bragg grating (FBG) was used as the mechanically tunable element enabling the rapid wavelength sweeping of the laser center wavelength. A simple algorithm to process the noisy acquired data and identify the peak of the BGS spectra was employed. For the first time, this type of configuration was used to reliably interrogate at least three fiber Bragg grating sensors with a standard wavelength spacing between the Bragg wavelengths of 3 nm, without risk of breaking the stretched fiber, using an FBG with a simple PZT driven mount as the tuning elements.  相似文献   
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