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91.
A. A. Ogloblin S. A. Goncharov T. L. Belyaeva A. S. Demyanova 《Physics of Atomic Nuclei》2006,69(7):1149-1154
Recently, it was supposed the nα light nuclei may have structures resembling the diluted gas of α particles which could be considered as Bose-Einstein condensate (αBEC) in nuclear systems. At the present time, the only more or less definite candidate for an αBEC state predicted by theory is the second 0+ state of 12C (E = 7.65 MeV) located near the threshold 12C → 3α. We discuss several possible experimental approaches to study the properties of interest of the 7.65-MeV level of 12C. Among them are shift of the positions of the rainbow minima in the inelastic scattering to this level, extraction of the
empirical inelastic form factor from the α and 3He scattering and its comparison with theoretical predictions, and getting information on the 8Be transfer reaction form factor. The conclusion was drawn that new measurements of 12C(α, α′) 12C(7.65) inelastic scattering at ∼120 MeV in the full angular range would be most adequate to solving the problem. The possibility
of observation of αBEC effects in heavier nα nuclei is also discussed. In particular, 112Ba is of great interest owing to possible existence of an α-particle “halo” outside the Z = N = 50 core.
The text was submitted by the authors in English. 相似文献
92.
H. G. Bohlen B. Gebauer M. von Lucke-Petsch W. von Oertzen A. N. Ostrowski M. Wilpert Th. Wilpert H. Lenske D. V. Alexandrov A. S. Demyanova E. Nikolskii A. A. Korsheninnikov A. A. Ogloblin R. Kalpakchieva Y. E. Penionzhkevich S. Piskor 《Zeitschrift für Physik A Hadrons and Nuclei》1993,344(4):381-393
The mass of10Li has been measured with two different reactions:9Be(13C,12N)10Li,E Lab=336 MeV, and13C(14C,17F)10Li,E Lab=337 MeV. The mass excess of 33.445(50) MeV is deduced from theQ-value measurement.10Li is found to be particle-unstable with respect to one-neutron emission by 0.42(5) MeV. In the analysis of the first reaction a low lying excited state is found at 0.38(8) MeV. This state and the ground state can be most probably identified as the 1+/2+-doublet coupled from the [π 1p3/2 ?ν 1p 1/2] configuration, the 1+-state being the ground state. The (13C,12N)-reaction populates the 1+-state strongly due to a spin-isospin-flip character of the dominant part of the transition amplitude. The 2+-member corresponds to the mass given by Wilcox et al. A second excited state is observed at 4.05(10) MeV with a width of 0.7(2) MeV, it can be associated with theν 1d 5/2-strength. The second reaction is fully supporting the interpretation of the ground state doublet. The excited state at 4.05 MeV is not observed in this reaction and indeed it should not, because the reaction does not populate in first order excited neutron configurations. The levels are well described by mean field calculations including pairing correlations. The lowest resonance in the calculations is theν 1/2?-configuration, whereas theν 1/2+-configuration shows at the neutron threshold a strong non-resonant contribution. 相似文献
93.
94.
The Electronic tongue (ET) composed of different kind of potentiometric chemical sensors has been applied for the detection of urinary system dysfunctions and creatinine levels. The creatinine contents evaluated by ET were compared with those obtained by automated Jaffe’s method and GC-MS, obtaining a satisfying agreement for both methods. Partial least square regression discriminate analysis (PLS-DA) and feed forward back-propagation neural network (FFBP NN) classified 51 urine specimens from healthy volunteers in four classes, according to the creatinine content, showing that both techniques can satisfactorily differentiate urines according to this parameter. The best accuracy result of 92.2% correct classification of unknown samples was achieved with FFBP NN. Moreover, the possibility of ET system to distinguish between urine samples of healthy patients, and those with malignant and non-malignant tumor diagnosis of bladder has been shown. 相似文献
95.
Borisova TN Voskressensky LG Soklakova TA Kulikova LN Varlamov AV 《Molecular diversity》2003,6(3-4):207-212
Tetrahydropyrrolo[3,2-c]pyridines and tetrahydropyrido[4,3-b]indoles undergo piperidine ring opening under the action of dimethyl acetylene dicarboxylate in alcohols or in aqueous dioxane, providing beta-(alk)oxy-substituted pyrroles (indoles) in moderate to high yields. 相似文献
96.
Il'in MM Semenova MG Belyakova LE Antipova AS Polikarpov YN 《Journal of colloid and interface science》2004,278(1):71-80
We report on the effect of a set of water-dispersible small-molecule surfactants (the main and the longest-hydrocarbon components of which are a citric acid ester of monostearate, a sodium salt of stearol-lactoyl lactic acid, and a polyglycerol ester of stearic acid) on molecular, thermodynamic, and functional properties of the major storage protein of broad beans (Vicia faba) legumin in different molecular states (native, heated, and acid-denatured). The interaction between legumin and the surfactants has been characterized by a combination of thermodynamic methods, namely, mixing calorimetry and multiangle laser static and dynamic light scattering. It was found that hydrogen bonds, electrostatic interactions, and hydrophobic contacts provided a basis for the interactions between the surfactants and both the native and the denatured protein in aqueous medium. Intensive association of the protein molecules in a bulk aqueous medium in the presence of the surfactants was revealed by static and dynamic laser light scattering. In consequence of this, both the surface activity and the gel-forming ability of legumin increased markedly, which has been shown by tensiometry, estimation of protein foaming capacity, and steady-state viscometry. A likely molecular mechanism underlying the effects of small-molecule surfactants on legumin structure-forming properties at the interface and in a bulk aqueous medium is discussed. 相似文献
97.
Chemistry of Heterocyclic Compounds - The minireview considers the current trends in the synthesis of some biologically active compounds based on 2-aminobenzothiazole. The presented information... 相似文献
98.
Alexander V. Yakimansky Tamara K. Meleshko Dmitrii M. Ilgach Maria A. Bauman Tatiana D. Anan'eva Larisa G. Klapshina Svetlana A. Lermontova Irina V. Balalaeva William E. Douglas 《Journal of polymer science. Part A, Polymer chemistry》2013,51(20):4267-4281
An approach to the synthesis of new regular graft‐copolymers polyimide (PI)‐graft‐polymethacrylic acid is elaborated, including (1) synthesis of multicenter PI macroinitiators, (2) controlled ATRP of tert‐butylmethacrylate on the prepared macroinitiators, and (3) protonolysis of tert‐butyl ester groups of side chains of the resulting PI‐graft‐poly(tert‐butylmethacrylate). Experimental conditions for attaining complete conversions of the first and the third stages of the process are determined by means of 1H NMR and FTIR‐spectroscopy. Polymer products of the first and the second stages of the process, as well as poly(tert‐butylmethacrylate) side chains cleaved from the PI‐graft‐poly(tert‐butylmethacrylate) copolymers by complete decomposition of the PI backbone under alkaline hydrolysis conditions, are characterized by GPC. The kinetics of poly(tert‐butylmethacrylate) chain growth on a PI macroinitiator under ATRP conditions are studied. The results obtained provide evidence for the controlled character of the ATRP process and the regular structure of the synthesized graft‐copolymers. It is shown that PI‐g‐PMAA PI brushes are significantly more efficient intracellular delivery agents for the potential photosensitizer [tetra(4‐fluorophenyl)tetracyanoporhyrazine free base] than are the commonly used PEG‐micelles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4267–4281 相似文献
99.
Vera Yu. Mishina Irina V. Abrashina Andrei T. Teleshev Larisa K. Vasyanina Eduard E. Nifant'ev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2425-2434
Interaction between the equimolecular amounts of glycols (diatomic phenols) and phosphorous acid triamides in diglyme or without solvent gives phosphorus-bearing polyamidophosphites. The structure of these compounds was studied by NMR spectroscopy, and it was shown that a partial disproportionation of amidophosphite fragments into phosphite ones can occur in the course of their synthesis. The chemical properties of the obtained compounds are being studied. First rhodium complexes with polyamidophosphite ligands were obtained. These complexes are shown to be more active hydrogenation catalysts than the corresponding low-molecular complexes. 1 相似文献
100.