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151.
A method for internal calibration of ESCA (XPS ) spectra is described that permits the use of a simple relation between binding energy (Eb) and atomic charge (q) : Eb = kq + Eb0. This relation has been shown to hold for a large number of elements. In order to test these relations, a procedure is suggested that allows the calculation of the atomic charges in carbonyl complexes of chromium, iron and nickel from gas-phase and solid-state ESCA data. The agreement with theoretically calculated charge values is good.

The charge distribution in carbon monoxide has been estimated in a similar manner and the result is discussed in relation to other investigations.  相似文献   

152.
Photoelectron energy distributions of Ni(100) have been calculated in the photon energy range 30 – 80 eV. A strong resonance due to interband transitions appears at 5 eV binding energy. Its connection to the experimentally observed resonance, interpreted as a many-body phenomenon, is discussed.  相似文献   
153.
New calculations of the4P0 (1,2,3) therms of LiI** are reported which support those of Weiss against those of Holøien and Geltman. A corresponding revision of the spectral analysis of Berry is proposed.  相似文献   
154.
Three types of chloroplasts (Peak I, Peak II, and Peak III chloroplasts) isolated by counter-current distribution in aqueous polymer two-phase systems have been studied with respect to DNA content. (The characterization was performed by studying the buoyant density, the melting profile and the amount of DNA of each type). The DNA was found to differ between the three types of chloroplasts.  相似文献   
155.
Results from kinetic theory are reformulated in order to generalize previous equations for wave-wave interactions in magnetized plasmas.  相似文献   
156.
157.
Summary In the present review of liquid dynamics studies on liquid metals are reported. Particularly the case of liquid lead is reviewed because this case was carefully studied by neutron scattering technique,S(Q,ω) being determined at two widely different temperaturesT=623 K andT=1170 K and therefore different densities. In addition extensive supplementary MD simulations were made using a 16 384-particle system. The simulations ranged from a determination of an effective pair potential for lead to simulation of the density correlation functionsF(Q,t) andF s(Q,t), as well as the longitudinal and transversal current correlation functionsJ 1(Q,t) andJ T(Q,t). The MD simulation ?calibrated? via the experimentalS(Q) andS(Q,ω) was used to prolong the range of neutron data to draw conclusions regarding such quantities as dispersion relations for the current correlationsJ 1(Q,t) andJ T(Q,t), the generalized viscosity functions ν1(Q,t), ν1(Q) and νs(Q). Information regarding bulk viscosity νB(Q) is also gained. Conclusions are drawn regarding the relative importance of the derived pair potential form by comparison to corresponding hard-sphere data. The general framework of linearized hydrodynamic equations for the macroscopic situation transforming to visco-elastic equations of motion for finite wave-length and high frequency works well also for the case of a continuous potential. The region of transition from simple visco-elastic to hydrodynamic behaviour is occurring at wavelengths in the range (12÷20) ? for the cases studied. The spatial properties of the viscosity functions ν1(r), νs(r) and νB(r) are found to correlate well with the range of the radial distribution function for the liquid. The general results for liquid lead probably have wide range of applicability to other simple liquids with similarS(Q) andg(r) properties. The authors have agreed not to receive proofs for correction.  相似文献   
158.
159.

Phenolic compounds released and generated during hydrolysis inhibit fermentation of lignocellulose hydrolysates to ethanol by Saccharomyces cerevisiae. A wide variety of aromatic compounds form from lignin, which is partially degraded during acid hydrolysis of the lignocellulosic raw material. Aromatic compounds may also form as a result of sugar degradation and dare present in wood as extractives. The influence of hydroxy-methoxy-benzaldehydes, diphenols/quinones, and phenylpropane derivatives on S. cerevisiae cell growth and ethanol formation was assayed using a defined medium and oxygen-limited conditions. The inhibition effected by the hydroxy-methoxy-benzaldehydes was highly dependent on the positions of the substituents. A major difference in inhibition by the oxidized and reduced form of a diphenol/quinone was observed, the oxidized form being the more inhibitory. The phenylpropane derivatives were examined with respect to difference in toxicity depending on the oxidation-reduction state of the γ-carbon, the presence and position of unsaturated bonds in the aliphatic side chain, and the number and identity of hydroxyl and methoxyl substituents. Transformations of aromatic compounds occuring during the fermentation included aldehyde reduction, quinone reduction, and double bond saturation. Aromatic alcohols were detected as products of reductions of the corresponding aldehydes, namely hydroxy-methoxy-benzaldehydes and coniferyl aldehyde. High molecular mass compounds and the corresponding diphenol were detected as products of quinone reduction. Together with coniferyl alcohol, dihydroconiferyl alcohol was identified as a major transformation products of conifery aldehyde.

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160.
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