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1.
Phys Rev Lett ; 132(9): 092501, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489643

RESUMO

Three ΔI=1 bands with the πg_{9/2}⊗νg_{9/2} configuration have been identified in _{35}^{74}Br_{39}. Angular distribution, linear polarization, and lifetime measurements were performed to determine the multipolarity, type, mixing ratio, and absolute transition probability of the transitions. By comparing these experimental observations with the corresponding fingerprints and the quantum particle rotor model calculations, the second and third lowest bands are, respectively, suggested as the chiral partner and one-phonon wobbling excitation built on the yrast band. The evidence indicates the first chiral wobbler in nuclei.

2.
Appl Radiat Isot ; 66(6-7): 855-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18367400

RESUMO

The full-spectrum analysis (FSA) method was used to determine primordial activity concentrations (ACs) in soil, sand and ore samples, in conjunction with a HPGe detector. FSA involves the least-squares fitting of sample spectra by linear combinations of (238)U, (232)Th and (40)K standard spectra. The differences between the FSA results and those from traditional windows analyses (using regions-of-interest around selected photopeaks) are less than 10% for all samples except zircon ore, where FSA yielded an unphysical (40)K AC.

3.
Biochem J ; 98(2): 493-500, 1966 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-5941342

RESUMO

1. The heartwood of A. auriculiformis contains a typical mixture of analogues consisting of three isomeric flavan-3,4-diols, a dihydroflavonol, flavanone, flavonol and chalcone based on the 4',7,8-trihydroxyl pattern. These were resolved by preparative paper chromatography and preparative paper ionophoresis. 2. Crystalline (-)-teracacidin [(2R,3R,4R)-4',7,8-trihydroxy-2,3-cis-flavan-3,4-cis-diol] was obtained in high (10%) yield, and a new crystalline derivative of (-)-isoteracacidin [(-)-2,3-cis-3,4-trans isomer] was isolated. The crystalline methyl ether of a new (+)-2,3-trans-3,4-cis isomer was isolated. 3. The absolute configurations of (-)-isoteracacidin (2R,3R,4S) and of the (+)-2,3-trans-3,4-cis isomer (2R,3S,4S) were tentatively assigned on the basis of nuclear-magnetic-resonance spectroscopy, paper ionophoresis and paper-chromatographic comparison with the epimerization products of (-)-teracacidin. 4. Possible reasons for the absence of polymeric leuco-anthocyanidin tannins are discussed. 5. (+/-)-4',7,8-Trihydroxydihydroflavonol and (+/-)-4',7,8-trihydroxyflavanone were isolated for the first time. 6. The bark polyphenols consist mainly of polymeric leuco-delphinidins and leuco-cyanidins which redden exceptionally rapidly to light. The mechanism of this phenomenon is discussed.


Assuntos
Acacia , Benzopiranos , Fenômenos Químicos , Química , Cromatografia em Papel , Cromatografia em Camada Fina , Eletroforese , Técnicas In Vitro , Espectroscopia de Ressonância Magnética
4.
Biochem J ; 99(3): 604-9, 1966 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-4290475

RESUMO

1. The isolation of aspalathin, the principal phenolic constituent in the leaves of Aspalathus linearis, is described and its properties are discussed. 2. The compound has been identified as 3'-C-beta-d-glucopyranosyl-2',3,4,4',6'-pentahydroxydihydrochalcone by the preparation and analysis of various derivatives, by photochemical oxidation to 2,3-dihydroiso-orientin and by nuclear-magnetic-resonance studies.


Assuntos
Acetofenonas/análise , Fenômenos Químicos , Química , Cromatografia em Papel , Espectroscopia de Ressonância Magnética , Oxirredução , Ácido Periódico , Espectrofotometria
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