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991.
A. Neußer H. Hübel G.B. Hagemann S. Bhattacharya P. Bringel D. Curien O. Dorvaux J. Domscheit F. Hannachi D.R. Jensen A. Lopez-Martens E. Mergel N. Nenoff A.K. Singh 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):439-441
First evidence is presented for triaxial superdeformation in 170Hf. High-spin states in this nucleus have been investigated in a γ-ray coincidence measurement using the EUROBALL spectrometer
array. A new band was discovered which has moments of inertia that are very similar to the ones of triaxial superdeformed
bands in neighbouring Hf and Lu nuclei. The intensities with which these bands are populated are different from what may be
expected from calculated potential-energy minima.
Received: 11 September 2002 / Accepted: 15 October 2002 / Published online: 10 December 2002
RID="a"
ID="a"e-mail: neusser@iskp.uni-bonn.de
Communicated by D. Schwalm 相似文献
992.
993.
This review discusses the potential of Haberlea rhodopensis as a food additive. The following are described: plant distribution, reproduction, cultivation, propagation and resurrection properties; extraction, isolation and screening of biologically active compounds; metabolite changes during dehydration; phytotherapy-related properties such as antioxidant potential and free radical-scavenging activities, antioxidant skin effect, antibacterial activity, cytotoxic activity and cancer-modulating effect, radioprotective effect, chemoprotective effect, immunologic effect; present use in homoeopathy and cosmetics, pharmacological and economical importance; perspectives based on the ethnobotanical data for medicinal, cosmetic or ritual attributes. H. rhodopensis showed unique medical and pharmaceutical potential, related to antioxidant, antimicrobial, antimutagenic, anticancer, radioprotective, chemoprotective and immunological properties. H. rhodopensis extracts lack any cytotoxic activity and could be used in phytotherapy. The metabolic profiling of H. rhodopensis extracts revealed the presence of biologically active compounds, possessing antiradical and other physiological activities, useful for design of in vitro synthesised analogues and drugs. 相似文献
994.
戴世强 《应用数学和力学(英文版)》2001,22(3):261-269
IntroductionThePLKmethodisaneffectiveperturbationmethodandhasahistoryofmorethan 10 0yearsinitsadventanddevelopment (cf.Refs.[1- 6 ]) .Inthe 80softhenineteenthcentury ,Poincare ,Lindstedtetal.proposedatechniqueofstrainedparametersintheirstudyofcelestialmechanics.Th… 相似文献
995.
V. S. Kulikova M. M. Levitsky A. F. Shestakov A. E. Shilov 《Russian Chemical Bulletin》1998,47(3):435-437
The reaction of oxidation of 1,4-dimethylcyclohexane (DMCH) by perchloric acid at ~20 °C catalyzed by polyphenylferrosiloxane has been found. The chromatographic analysis has revealed the formation of several products, including the tertiary alcohol with 100% retention of the configuration of the initial configuration. The specific feature of the process is the following: along with the high stereospecific formation of the tertiary alcohol,cis-trans isomerization in the starting 1,4-DMCH is observed. The data obtained are discussed on the basis of the mechanism, including the formation of a ferryl intermediate with the subsequent transfer of the oxygen atom to the tertiary C?H bond of 1,4-DMCH through the intermediate complex with the five-coordinated carbon. 相似文献
996.
A spectrophotometric procedure is described for the determination of three phenolic sympathomimetic drugs: etilefrine hydrochloride, prenalterol hydrochloride and ritodrine hydrochloride. The method involves the use of 2,6-dichloro- and 2,6-dibromoquinone chlorimides as chromogenic reagents. The phenolic drugs produce a blue color, peaking from 610 to 630 nm. The colors produced obey Beer's law and are suitable for the quantitative determination of the named compounds. The molar ratios of the reactions were established and a proposal for the reaction pathway is given. The procedures described were applied successfully to the determination of the compounds in their dosage forms. The results showed that the proposed procedures compared favourably with the reference methods and satisfactory sensitivity, accuracy and precision (SD < 0.1 g ml–1) were noted. Detection limits are typically 0.2–0.4 g ml–1. Other advantages of the procedures are their simplicity and speed. 相似文献
997.
Integralmembraneproteinsarecriticaltoawidevarietyofcellularpsychologicalactivities,suchascytochromeoxidaseinmediatingelectrontransportandtheactivationofintracellularsignalsbytransmembranereceptorscoupledtoGproteins[1].Inthesemembraneactivities,themechan… 相似文献
998.
999.
《Analytical letters》2012,45(9-10):1037-1052
Abstract A high performance liquid chromatographic method for the rapid separation and quantitative determination of five barbiturates in pharmaceutical preparations and body fluids has been developed. A C18 reversed phase column was used and the barbiturates were detected at 235nm. A number of eluting systems were examined, the most suitable of them being, Ethanol:Propanol:Methanol:Water (26:5:29:40) at pH = 8.8. 相似文献
1000.
Pharmaceutical interaction of the most frequently used substances with fats: lanolin, white soft paraffin and vitamin A palmitate was studied. The mixtures were examined by TLC with different ratios of lanolin and vitamin A palmitate, and white soft paraffin and vitamin A palmitate. Vitamin A in the mixtures was determined by the UV spectrophotometric method according to BP 93. It was established that the rise of lanolin concentration resulted in an increased apparent content of vitamin A in fats as a consequence of lanolin absorption at the wave length of maximum absorption of vitamin A. By an increase of white soft paraffin concentration, an apparent decreased in the content of vitamin A in fats was obtained. Therefore, the suggested UV spectrophotometric method for vitamin A determination has a limited application on fats with high content of lanolin and white soft paraffin. 相似文献