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41.
We present new measurements of the α + 12C elastic and inelastic (to the states 4.44, 7.65, and 9.64 MeV) scattering at E lab = 110 MeV in the wide angular range from ~10° to 175°, which enable us to examine the condensate and cluster properties of the low-lying excited states in 12C. We present the diffraction-radius analysis of our data together with a considerable amount of the existing data. The magnitudes of the diffraction radii for the ground and the first excited (4.44 MeV) states are found to be equal, whereas they appear to be enhanced by ~0.6 fm both for 7.65 and 9.64 MeV states. This result shows that the radius of the Hoyle’s 0 2 + , 7.65 MeV state in 12C is by a factor of ~1.2–1.3 larger than that of the ground state. It is demonstrated that the direct transfer mechanism of 8Be dominates at the largest angles in all four reactions reported here. The configuration corresponding to the transfer of 8Be in its ground state (I π = 0+) with L = 0 turns out to be the most important for the 7.65 MeV state of 12C. Evidence of existence of some features of α-condensed structure of the Hoyle’s 0 2 + state in 12C was obtained: its enhanced radius and large contribution of α-particle configuration with L = 0.  相似文献   
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43.
The relativistic scattering was one of the scientific fields where Academician V.G. Kadyshevsky has made an important and highly cited contribution [1]. In this paper we discuss the high-energy dependencies of diffractive and non-diffractive inelastic cross-sections in view of the recent LHC data which reveal a presence of the reflective scattering mode.  相似文献   
44.
采用双硫腙显色分光光度法测定蒙药中痕量铅,该方法具有简单、快速、灵敏等特点,用以测定蒙药中的痕量铅,获得了满意的结果.该方法线性范围为0.00-0.40μg/mL Pb2 ,相关系数0.9993.回收率95%-ll0%.  相似文献   
45.
To identify the structure of emissive tunnel recombination sites in the emulsion microcrystals of silver bromide AgBr(I) with iodine contaminations and to determine the role of an emulsion medium in their formation, the temperature dependence of the luminescence spectra in the range from 77 to 120 K, the kinetics of the growth of the maximum luminescence intensity value at λ ≈ 560 nm, and the luminescence flash spectrum stimulated by the infrared light are investigated. Two types of the AgBr1 – x(I x ) (x = 0.03) microcrystals—namely, obtained in an aqueous solution and on a gelatin substrate—are used in the studies. It is established that the emissive tunnel recombination sites with a luminescence maximum at λ ≈ 560 nm in AgBr1 – x(I x ) (x = 0.03) are the {(I a - I a - )Ag i + } donor–acceptor complexes with the I a - iodine ions located in neighbor anionic sites of the AgBr(I) crystal lattice, next to which the Ag i + interstitial silver ion is positioned. With an increase in the temperature, the {(I a - I a - )Ag i + } sites undergo structural transformation into the {(I a - I a - )Agin+} sites, where n = 2, 3, …. Moreover, the {(I a - I a - )Ag in + } sites (n = 2) after the capture of an electron and hole also provide the tunnel recombination with a luminescence maximum at λ ≈ 720 nm. The influence of an emulsion medium consists in that gelatin interacts with the surface electron-localization sites, i.e., the interstitial silver ions Ag in + , n = 1, 2, and forms the complexes {Ag in 0 G+} (n = 1, 2) with them. The latter are deeper electron traps with a small capture cross section as compared to the Ag in + sites (n = 1, 2) and that manifest themselves in that the kinetics of the luminescence growth in AgBr(I) to a stationary level at λ ≈ 560 nm is characterized by the presence of “flash firing.” At the same time, the luminescence flash stimulated by IR light, for which the Ag in + (n = 1, 2) electron-localization sites are responsible, is absent. It is supposed that the electrons localized on the {Ag in + G+} complexes (n = 2) retain the capability for emissive tunnel recombination with holes localized on paired iodine sites with a luminescence maximum at λ ≈ 750 nm.  相似文献   
46.
为改善海洋与水声环境预报质量,针对常规观测成本高、资料利用率低等问题,将适应性观测方法应用于海洋声学领域。结合海洋-声学耦合模式与集合卡尔曼转换敏感区诊断方法,以东中国海宫古海峡北部区域为验证区,计算并分析不同条件下海洋环境敏感区与声学敏感区分布,通过观测系统模拟试验验证适应性观测对验证区预报的提升效果。结果表明,两种敏感区位置随时间间隔增加均向验证区上游移动,海洋环境敏感区相比于声学敏感区分布更为集中,且平移特征更明显;对海洋环境敏感区和声学敏感区添加适应性观测均能提升海洋与水声环境的预报质量,提升效果随时间间隔增加而减小,在某种类型敏感区的适应性观测对相对应参数的预报质量提升效果优于对其他类型敏感区进行观测的效果。  相似文献   
47.
The paper studies the problems of well-posedness (invertibility) of elliptic operators acting between the Sobolev–Slobodetskii spaces, the Stepanov spaces, and some other spaces. Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 57, Suzdal Conference–2006, Part 3, 2008.  相似文献   
48.
We argue that the nucleon seen in the Bjorken scaling region is a gas of quasi-free partons. As x decreases, for certain values of Q 2 the partons in a nucleon coalesce to a liquid (saturation). Experimentally this phenomenon is manifested as the turn-over of the structure function derivatives. The phenomenon can be quantified in the framework of statistical models, percolation and other approaches to collective effects in the strongly interacting matter. Similarities and differences between the case of lepton-hadron, hadron-hadron and heavy-ion collisions are discussed.  相似文献   
49.
50.
Conclusions Heterocyclic compounds of the 2-imidazoline, benzimidazole and benzoxazole series, containing the ferrocenyl radical, were obtained from the hydrochlorides of the iminoesters of ferrocenecarboxylic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1567–1569, July, 1971.  相似文献   
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