Measured lifetimes of states in 197Au and a critical comparison with the weak-coupling core-excitation model

The lifetimes of five excited states in ¹⁹⁷Au up to an excitation energy of 885 keV were measured by the recoil-distance method (RDM). These levels were populated by Coulomb excitation using both 90 MeV ²⁰Ne and 120 MeV ³⁵Cl ion beams. The experimentally determined spectroscopy of the low-lying levels $\text{3}\text{2}{}^{\mathrm{+}}$ (ground state) and $\text{1}\text{2}{}^{\mathrm{+}}$, $\text{3}\text{2}{}_2{}^{\mathrm{+}}$, $\text{5}\text{2}{}^{\mathrm{+}}$, and $\text{7}\text{2}{}^{\mathrm{+}}$ at 77.3, 268.8, 278.9, and 547.5 keV excitation energy, respectively, has been critically compared with the detailed predictions of the de-Shalit weak-coupling core-excitation model. When the model is taken to represent the case of a $\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}$ proton hole coupled to a ¹⁹⁸Hg core, the model parameters obtained are in accord with the criteria implicit for weak core coupling and, at the same time, are in remarkably good agreement with virtually all measured E2 and M1 transition rates.     

Physicochemical properties of alkali metal cation-TCNQ anion radical salts

Simple alkali metal cation-TCNQ anion radical salts are classified in two groups from the differences in their physicochemical properties and crystal structures. Li-, Na-, K-, and Rb(I)-TCNQ are comprised in Group A. Li-TCNQ exhibits distinct behavior from other salts in Group A. Rb(II)- and Cs-TCNQ belong to Group B. Phase transitions, electrical conductivities, and absorption spectra in these simple salts are closely related to their crystal structures.     

Novel sign-alternation rule for the triplet state in aromatic systems

Within the framework of the LCAO -MO theory, a novel sign-alternation rule has been found empirically for the lowest excited ππ* triplet state in the alternant aromatic system. This rule can be applied to identify the phosphorescent state.     

Application of pattern recognition to structure-activity problems: Use of minimal spanning tree

A graph-theoretical algorithm based on the minimal spanning tree (MST) is applied to structure—activity problems. The method is helpful in interpreting the results of cluster analysis, and becomes useful by combining with the mapping method that illustrates approximations of a multidimensional data structure. The antibacterial spectra of cephalosporins are analyzed by the MST approach and a linear mapping method. The main diameter obtained by MST gives the representative data set and clarifies the substituent effect on the antibacterial spectra. Relations between the central nervous system activity of benzodiazepine derivatives and their physicochemical parameters are also analyzed by MST and nonlinear mapping methods. These results for cephalosporins and benzodiazepines prove that MST is very useful in understanding the position of compounds in feature space and their activities.     

Spectrophotometric determination of strychnine and methylatropine by extraction with tetrabromophenolphthalein ethyl ester

A new application of monoacidic dyes is reported for the determination of strychnine and methylatropine. The method is based on solvent extraction into 1,2-dichloroethane of the ion-pair or addition compound formed between tetrabromophenolphthalein ethyl ester and quaternary ammonium salts or alkaloids. The absorbance of the extracts is linearly dependent on the concentration of strychnine or methylatropine initially present in the aqueous solution.     

Semi-stable curves on algebraic surfaces and logarithmic pluricanonical maps

Mathematische Annalen -     

Naturalnes in supersymmetric GUTS

We propose a resummation of QCD radiative corrections in large transverse momentum hadronic processes, based on the introduction of an infrared cut-off, linked to the confinement radius. An analysis of the inclusive reactionspp → π⁰ X andpp → γX and of γ/π⁰ ratio is presented.     

Structures and fusion parameters of methoxycarbonyl-benzenes and -naphthalenes

The heats of fusion of methoxycarbonyl-benzenes (12 isomers) and -naphthalenes (32 isomers) have been determined by the differential scanning calorimetric method and the correlation of numbers and positions of methoxycarbonyl groups against the parameters of fusion (melting point, enthalpy and entropy) are discussed. The enthalpy—entropy relationship shows two correlation lines depending on the symmetry of the molecules including the positions of the substituents.