Gross shell structure at high spin in heavy nuclei

Experimental nuclear moments of inertia at high spins along the yrast line have been determined systematically and found to differ from the rigid-body values. The difference is attributed to shell effects and these have been calculated microscopically. The data and quantal calculations are interpreted by means of the semiclassical Periodic Orbit Theory. From this new perspective, features in the moments of inertia as a function of neutron number and spin, as well as their relation to the shell energies can be understood. Gross shell effects persist up to the highest angular momenta observed.Comment: 40 pages total; 22 pages text, 19 figures sent as 27 .png file

Species diversity and synanthropization of Minsk suburban forests

The variety of the most common phytocoenosis of the suburb Minsk is established. In all are revealed 257 species. Their greatest quantity is fixed in pine forests (179) and birch groves (163). Before the unviolated phytocoenosis the greatest quantity of species is revealed before the fir groves. The level of synanthropic species before the wood and bushy tier on the average composes 50%. Before the ground cover the portion of synanthropic species before average 30% reaches maximum with 4–5 stages of recreational digression

Low temperature mixed spin state of Co3+ in LaCoO3 evidenced from Jahn-Teller lattice distortions

One- and multi-phonon excitations of the single crystalline LaCoO3 were studied using Raman spectroscopy in the temperature region of 5 K - 300 K. First-order Raman spectra show a larger number of phonon modes than allowed for the rhombohedral structure. Additional phonon modes are interpreted in terms of activated modes due to lattice distortions, arising from the Jahn-Teller (JT) activity of the intermediate-spin (IS) state of Co3+ ions. In particular, the 608-cm-1 stretching-type mode shows anomalous behavior in peak energy and scattering intensity as a function of temperature. The anomalous temperature dependence of the second-order phonon excitations spectra is in accordance with the Franck-Condon mechanism that is characteristic for a JT orbital order.Comment: 11 pages, 9 figures, to be published in J. Low. Temp. Physic

Dynamical lattice instability versus spin liquid state in a frustrated spin chain system

The low-dimensional s=1/2 compound (NO)[Cu(NO3)3] has recently been suggested to follow the Nersesyan-Tsvelik model of coupled spin chains. Such a system shows unbound spinon excitations and a resonating valence bond ground state due spin frustration. Our Raman scattering study demonstrates phonon anomalies as well as the suppression of a broad magnetic scattering continuum for temperatures below a characteristic temperature, T<T*=100K. We interpret these effects as evidence for a dynamical interplay of spin and lattice degrees of freedom that might lead to a further transition into a dimerized or structurally distorted phase at lower temperatures.Comment: 5 pages, 6 figure

Momentum distribution in heavy deformed nuclei: role of effective mass

The impact of nuclear deformation on the momentum distributions (MD) of occupied proton states in $^{238}$U is studied with a phenomenological Woods-Saxon (WS) shell model and the self-consistent Skyrme-Hartree-Fock (SHF) scheme. Four Skyrme parameterizations (SkT6, SkM*, SLy6, SkI3) with different effective masses are used. The calculations reveal significant deformation effects in the low-momentum domain of $K^{\pi}=1/2^{\pm}$ states, mainly of those lying near the Fermi surface. For other states, the deformation effect on MD is rather small and may be neglected. The most remarkable result is that the very different Skyrme parameterizations and the WS potential give about identical MD. This means that the value of effective mass, being crucial for the description of the spectra, is not important for the spatial shape of the wave functions and thus for the MD. In general, it seems that, for the description of MD at $0\le k \le 300$ MeV/c, one may use any single-particle scheme (phenomenological or self-consistent) fitted properly to the global ground state properties.Comment: 14 pages, 6 figure

РЫНОК АГРАРНОЙ РАБОЧЕЙ СИЛЫ: ПАРАМЕТРЫ ФОРМИРОВАНИЯ И РАЗВИТИЯ

Implementation of the State program for agricultural business development in the Republic of Belarus for 2016–2020 is determined by the highly skilled agricultural workforce performance able to carry out the production processes at a high technical and technological level. The agrarian workforce market has its own characteristics and is determined by a complex of conditions (demographic, economic and social). An efficient mechanism of its regulation should be established for timely problems solving. The quantitative and qualitative parameters of the formation and development of the agrarian workforce market in Belarus are analyzed in the article, trends and reasons of supply and demand imbalance were identified. Study of the agrarian workforce market formation shows that the demand for labor in the agro-industrial complex is determined by requirements of its enterprises and industries, and supply for labor is determined by territorial size and population structure. Households, education institutions and demographic factors are important aspects of labor supply sources in the market. When mostly economic parameters of agrarian enterprises and industries in AIC determine the labor demand. There is a lack of trained personnel and skilled workers in agricultural organizations. At the same time there are an excessive number of trained agricultural personnel. Moreover a high flow index of agricultural personnel is observed for a number of years. Based on research findings it was concluded that regulation of the agrarian workforce market should be carried out via strengthening of cooperation between educational institutions and potential employers, as well as by elaboration of new labor motivation instruments. Along with this, the importance of adapting agricultural organizations personnel to technical and technological and social changes is emphasized.Реализация Государственной программы развития аграрного бизнеса в Республике Беларусь на 2016–2020 гг. определяется наличием высококвалифицированной аграрной рабочей силы, которая способна осуществлять процессы производства на высоком технико-технологическом уровне. Рынок аграрной рабочей силы имеет своиособенности и определяется комплексом условий (демографических, экономических, социальных). Для своевременного решения возникающих на нем проблем необходим эффективный механизм его регулирования. В этой связи в статье проанализированы количественные и качественные параметры формирования и развития рынка аграрной рабочей силы Беларуси, выявлены тенденции и раскрыты причины дисбаланса спроса и предложения. Изучение основ формирования рынка аграрной рабочей силы показывает, что спрос на рабочую силу в АПК обуславливается потребностью его предприятий и отраслей, а предложение – исходя из территориальной численности и структуры населения. При этом важными аспектами формирования предложения рабочей силы на рынке выступают домашние хозяйства, учреждения образования и демографические факторы, в то время как спросв большей степени определяется экономическими параметрами развития предприятий и отраслей АПК. При избытке подготовленных кадров специалистов и квалифицированных рабочих ощущается их недостаток в сельскохозяйственных организациях, кроме того, на протяжении ряда лет наблюдается высокий показатель текучести аграрных кадров. По результатам исследований сделан вывод, что регулирование рынка аграрной рабочей силы должно осуществляться через усиление взаимодействия между образовательными учреждениями и потенциальными работодателями, а также выработку последними новых инструментов механизма мотивации труда. Наряду с этим подчеркивается важность адаптации персонала сельскохозяйственных организаций к технико-технологическим и социальным изменениям