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71.
Es war Ziel dieser Arbeit, zu ermitteln, welchen Einfluß höhere Dosen von Stickstoffdüngemitteln in Form von KNO3 auf die Menge des in der Pflanze fixierten Luftstickstoffs haben. Als Versuchspflanze wählten wir Pferdebohnen (Vicia faba, Chlumetzer Abart) wegen ihrer vielseitigen Verwendung in der Landwirtschaft und ihrer besonderen experimentellen Eignung.  相似文献   
72.
Abstract

The suitability of three GC-ECD systems for the separation of a model mixture containing various congeners of PCBs together with persistent chlorinated aromatics (pesticides and their metabolites, industrial chemicals) was tested. Analyses were performed on two parallel capillaries, the stationary phase of one of them was always in routine practice very common 5% phenyl-methylpolysiloxane, the second one was either 50% phenylmethylpolysiloxane or 7% phenyl-7% cyanopropyl-methylpolysiloxane. The number of unresolved (coeluted) analytes was significantly reduced in these systems and thus unbiased quantitation of PCBs and other components used for regulation was possible. The utilization of this type of multidimensional chromatography for rapid and reliable analysis of real samples (fish oil, human fat) was documented.  相似文献   
73.
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized. The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy.  相似文献   
74.
The results of NMR/ON measurements on56,57,60Co isotopes in iron are presented in the paper. To avoid the uncertainties caused by local demagnetizing field inhomogeneities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factors ratios 57/ 60=1·805(20), 60/ 56 = 0·761(20), 56/ 57 = 0·726(20) and hyperfme anomalies56 60 = –0·036(10),60 57 = 0·017(10) and57 56 = 0·018(10) have been calculated from the experimental results.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research.  相似文献   
75.
In the framework of path integrals we present a solution to the Schrödinger equation for a free particle confined to the half-linex > 0. A solution in question corresponds to the boundary condition (/x) (0,t)= (0,t) where is a real constant.  相似文献   
76.
77.
The energy dependent parameter characterizing the leading particle effect allows to restore the scaling in proton-proton and antiproton-proton multiplicity distributions from Serpukhov until highest available CERN \(S \bar ppS\) collider energies. The identification of theoretical second dispersions with the experimental ones represents one of the basic ingredients in the quantum statistical bosonic approach applied in the present contribution. The KNO scaling at the ISR energies as well as the Worblewski relation for the second dispersions at the \(S \bar ppS\) collider energies arise quite naturally; similar phenomena might appear at higher energies too. Some predictions for 2 and 10 TeV cms energies are specified.  相似文献   
78.
Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()2 appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm.  相似文献   
79.
The validity of local parton-hadron duality within the framework of HERWIG and JETSET event generators is investigated. We concentrate one + e annihilations in LEP 2 energy range as these interactions provide theoretically the cleanest condition for the discussion of this concept. We conclude that the concept of local parton-hadron duality is not valid in either of the two generators considered.  相似文献   
80.
We show that the Boolean power of an orthomodular latticeL is atomic if and only if bothL and the underlying Boolean algebraB are atomic. We describe the set of all atoms in the Boolean power.  相似文献   
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