Self-energy radiative corrections in hydrogen-like systems

The one-photon self-energy radiative level shift of an electron in a Coulomb field is examined. An expression for the level shift which is suitable for direct numerical evaluation, for Z in the range 10–110, is obtained. It is based on the known Coulomb radial Green's functions and not on a power series expansion in Zα. In the following paper, the numerical evaluation of the level shift for the $\text{1S}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ state is described.     

Numerical evaluation of the 1S12-state radiative level shift

The one-photon self-energy radiative level shift for an electron in a Coulomb potential is evaluated numerically for the $\text{1S}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ state. The evaluation is done for values of the nuclear charge Z = 10, 20,…, 110. The errors in the values obtained are estimated to be less than 0.1 %. The results are compared with the results of previous calculations. The evaluation is based on the expressions given in the preceding paper.     

STIMULATION OF APPEARANCE OF EXTRAPLASTIDIC TETRAPYRROLES BY A PHOTOOXIDATIVE TREATMENT OF THE PLASTIDS*

In the mustard seedling (Sinapis alba L.) the appearance of photodetectable phytochrome and synthesis of relatively abundant cytosolic hemoproteins (nitrite reductase, ascorbate peroxidase) are stimulated rather than impaired by a photooxidative treatment of the plastids. While the ability to synthesize protoporphyrin IX from exogenous 5-aminolevulinic acid was preserved in the photooxidatively damaged plants, protochlorophyll and chlorophyll accumulation was no longer possible. It appears from our data that in higher plants the pathway of tetrapymole synthesis up to protoporphyrin IX is not adversely affected by a photooxidative treatment of the plastids that destroys the capacity of the organelle to synthesize chlorophyll.     

Gradient formation of anthocyanin in seedlings of Fagopyrum and Sinapis unilaterally exposed to red and far-red light

Abstract— Anthocyanin synthesis was measured in hypocotyl halves excised from Fagopyrum and Sinapis seedlings irradiated unilaterally or equilaterally with red or far-red light. Although no phototropic curvatures are produced by red or far-red exposure, a significant gradient in anthocyanin formation was observed for Fagopyrum seedlings and the trend for gradient formation is present in Sinapis seedlings. The gradient production in Fagopyrurn is correlated with this tissue's greater optical density. Since the intensities used do not inhibit elongation completely (through the phytochrome system) and an intensity gradient is present in the tissue (as evidenced by anthocyanin formation) it is concluded that (a) a steeper light gradient is required to induce phototropic curvatures or (b) a diffusible material affecting elongation growth prevents any differential from being established across the tissue.     

Identification of active sites in gold-catalyzed hydrogenation of acrolein

The active sites of supported gold catalysts, favoring the adsorption of C=O groups of acrolein and subsequent reaction to allyl alcohol, have been identified as edges of gold nanoparticles. After our recent finding that this reaction preferentially occurs on single crystalline particles rather than multiply twinned ones, this paper reports on a new approach to distinguish different features of the gold particle morphology. Elucidation of the active site issue cannot be simply done by varying the size of gold particles, since the effects of faceting and multiply twinned particles may interfere. Therefore, modification of the gold particle surface by indium has been used to vary the active site characteristics of a suitable catalyst, and a selective decoration of gold particle faces has been observed, leaving edges free. This is in contradiction to theoretical predictions, suggesting a preferred occupation of the low-coordinated edges of the gold particles. On the bimetallic catalyst, the desired allyl alcohol is the main product (selectivity 63%; temperature 593 K, total pressure p(total) = 2 MPa). From the experimentally proven correlation between surface structure and catalytic behavior, the edges of single crystalline gold particles have been identified as active sites for the preferred C=O hydrogenation.     

Synthesis and characterization of a new benzofulvene polymer showing a thermoreversible polymerization behavior

A new polymer based on a functionalized benzofulvene moiety has been synthesized by spontaneous polymerization of the monomer in the solid state. This polymer shows a very high molar mass, high solubility in the most common organic solvents, and thermoreversible polymerization properties. An interesting application in synthesis is reported.     

Asymmetric synthesis of α-hydroxy-esters via ester enolates

3-Phenylpropionates of chiral alcohols derived from (+)-camphor are oxidized by Mo0₅· Py·HMPT (MoOPH) with high diastereoselectivity.     

Ueber die Bestimmung der Phosphors?ure

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