The effect of macro- and microfertilizers on agrochemical soil characteristics and spring wheat yield under conditions of the Right bank of the Volga-River in Saratov region

The paper specifies how the application of micro- and macrofertilizes changes typical black soil nutrient regime and physicochemical properties in spring wheat plantings. It was determined that the most acceptable nutrient regime was formed with combined usage of ammophos and such chemicals as Micromac and Microel. During these experiments nitrogen concentration amounted to 8.50 and 8.25 mg kg -1of the soil, and available phosphorus was 60.0 and 57 mg kg-1, respectively. The control gave the maximum amount of exchangeable potassium (242.5 mg kg-1), whereas the lowest rate was registered with combined usage of Micromac and Microel against the background of ammophos (231.6 mg kg-1). At the end of growth the nutrient regime significantly degraded due to the increasing plant nutrition of spring wheat. The influence of fertilizers on soil cation content was analyzed. Total absorbed bases insignificantly increased in applying fertilizers compared to the control, particularly with combined usage of micro and macrofertilizers, when this amount reached 44.45 mg-equiv per 100 g of soil. The highest yield has been observed with combined application of micro- and macrofertilizers, reaching 1.86 t ha-1, while the lowest yield has been shown in the control (1.22 t ha-1). The amount of calcium and magnesium cautions increased within SAC

Quantum tunneling dynamics in a complex-valued Sachdev-Ye-Kitaev model quench-coupled to a cool bath

Theoretical Physic

Расчетное обоснование механической безопасности Конгресс-холла в Челябинске

Aims of research. The article is devoted to actual problems of computational analysis of stress-strain state, strength and stability of load-bearing structures with allowance for the main and special combinations of loads and impacts, comparison of the results of alternative structural analysis of unique cultural and business complex “Congress Hall” in Chelyabinsk. The natural conditions of the area of location of this object and main load-bearing structures of the object are described. Besides, characteristic and design loads, their combinations, formulation of objectives of computational research and methods of solution are presented. Methods. Space discretization and solution of the corresponding problems of mathematical (numerical) and computer modelling of the considering unique building were carried out with the use of finite element method. Detailed finite element models of the coupled system “combined foundation - loadbearing structures” and its fragments (subsystems) were developed and verified. They adequately reflect geometric-stiffness, inertial and load parameters of the object and the resulting stress-strain state. Progressive collapse analysis are under consideration as well. Licensed, certified and verified (by the Russian Academy of Architecture and Construction Sciences) finite element software package “ANSYS Mechanical” was used. Results. The resulting parameters of stress-strain state, strength and dynamics of load-bearing structures of the building with allowance for design (in accordance with design codes) combinations of vertical and wind loads are considered. Besides, information about results of progressive collapse analysis is presented. Thus, a reasonable conclusion is made about the reliability of the criterion parameters of strength, stability and dynamics of the load-bearing structures of the object.Цели. Статья посвящена актуальным вопросам расчетных исследований напряженно-деформированного состояния (НДС), прочности и устойчивости основания и несущих конструкций при основных и особых сочетаниях нагрузок и воздействий, сравнительного анализа результатов альтернативных расчетов уникального проектируемого объекта строительства - общественно-делового центра «Конгресс-холл» в Челябинске. Описаны природные условия района расположения здания, устройство комбинированного основания, фундаментов и несущих конструкций объекта, основные и особые нагрузки (расчетные и нормативные) и их сочетания, постановка задач расчетных исследований, инструментарий их решения и полученные результаты. Методы. Дискретизация по пространству и решение результирующих задач математического (численного) моделирования состояния объекта осуществлялись методом конечных элементов в перемещениях. Построены, разработаны и проверены подробные конечноэлементные модели системы «комбинированное основание - несущие конструкции здания» и отдельных подсистем, адекватно отражающие геометрико-жесткостные, инерционные и нагрузочные характеристики объекта и результирующее НДС, проанализирована устойчивость против прогрессирующего обрушения. Все основные расчеты проведены с использованием лицензионного конечноэлементного программного комплекса ANSYS Mechanical, верифицированного в Российской академии архитектуры и строительных наук (РААСН). Результаты. Рассмотрены результирующие параметры НДС, прочности и динамики основания и несущих конструкций объекта при нормативно-регламентированных сочетаниях вертикальных и ветровых нагрузок, а также результаты расчетов на устойчивость против прогрессирующего обрушения. В заключении делается обоснованный вывод о достоверности полученных расчетами критериальных параметров, определяющих прочность, устойчивость и динамику несущих конструкций объекта

Status of the Lake Baikal Experiment

We review the present status of the Baikal Underwater Neutrino Experiment and report on neutrino events recorded with the detector stages NT-36 and NT-96.Comment: 5 pages, 4 PostScript figures, uses here.sty and mine.sty, submitted to the Proc. of 5th Int. Workshop on Topics in Astroparticle and Underground Physics (LNGS INFN, Assergi, September 7-11, 1997

Registration of atmospheric neutrinos with the Baikal neutrino telescope

We present first neutrino induced events observed with a deep underwater neutrino telescope. Data from 70 days effective life time of the BAIKAL prototype telescope NT-96 have been analyzed with two different methods. With the standard track reconstruction method, 9 clear upward muon candidates have been identified, in good agreement with 8.7 events expected from Monte Carlo calculations for atmospheric neutrinos. The second analysis is tailored to muons coming from close to the opposite zenith. It yields 4 events, compared to 3.5 from Monte Carlo expectations. From this we derive a 90 % upper flux limit of 1.1 * 10^-13 cm^-2 sec^-1 for muons in excess of those expected from atmospheric neutrinos with zenith angle > 150 degrees and energy > 10GeV.Comment: 20 pages, 11 figure

A 800-kV and 32-kJ pulse generator

The characteristics of oil-insulated 8-stage Marx generator aimed at charging water-insulated line of STRAUS-R electron beam accelerator are presented. Two IEPM-100-0.4 capacitors are installed in each stage. Switches in the first three stage are 100-kV gas-filled trigatrons while in other stages – two-electrode trigatrons. Operation delay time is 108±5 ns at electric strength reserve of each switch being equal to ~ 80%. The circuit inductance is ~1.4 µH.Приведены характеристики маслоизолированного восьмикаскадного генератора (ГИН) Аркадьева-Маркса для зарядки до 700 кВ за < 1 мкс водоизолированной линии ускорителя пучка электронов СТРАУС-Р. В каждом каскаде установлено по два конденсатора ИЭПМ-100-0.4. Коммутаторы в первых трех каскадах – газонаполненные тригатроны на 100 кВ, в остальных – двухэлектродные. Время задержки срабатывания 108+-5 нс при запасе электропрочности каждого разрядника ̴ 80%. Индуктивность контура ГИН ̴ 1,4 мнГн.Наведено характеристики маслоізольованого восьмикаскадного генератора (ГІН) Аркадьєва-Маркса для зарядки до 700 кВ за 1 мкс водоізольованої лінії прискорювача пучка електронів СТРАУС-Р. У кожному каскаді встановлено по два конденсатора ІЕПМ-100-0.4. Комутатори в перших трьох каскадах – газонаповнені тригатрони на 100 кВ, в інших – двохелектродні. Час затримки спрацьовування 108+-5 нс при запасі електроміцності кожного розрядника ̴ 80%. Індуктивність контуру ГІН ̴ 1,4 мкГн

The Lake Baikal neutrino experiment

We rewiew the present status of the Baikal Neutrino Project and present the results of a search for high energy neutrinos with the detector intermediate stage NT-96.Comment: 3 pages, 2 figures, to appear in the Proceedings of Sixth International Workshop on Topics in Astroparticle and Underground Physics (TAUP99), September 6-10, 1999, Pais, Franc

The Baikal Deep Underwater Neutrino Experiment: Results, Status, Future

We review the present status of the Baikal Underwater Neutrino Experiment and present results obtained with the various stages of the stepwise increasing detector: NT-36 (1993-95), NT-72 (1995-96) and NT-96 (1996-97). Results cover atmospheric muons, first clear neutrino events, search for neutrinos from WIMP annihilation in the center of the Earth, search for magnetic monopoles, and -- far from astroparticle physics -- limnology.Comment: Talk given at the Int. School on Nuclear Physics, Erice, Sept.199

Variable G and Λ\Lambda: scalar-tensor versus RG-improved cosmology

We study the consequences due to time varying $G$ and $\Lambda$ in scalar-tensor theories of gravity for cosmology, inspired by the modifications introduced by the Renormalization Group (RG) equations in the Quantum Einstein Gravity. We assume a power-law scale factor in presence contemporarily of both the scalar field and the matter components of the cosmic fluid, and analyze a special case and its generalization, also showing the possibility of a phantom cosmology. In both such situations we find a negative kinetic term for the scalar field $Q$ and, possibly, an equation-of-state parameter $w_Q<-1$. A violation of dominant energy condition (DEC) for $Q$ is also possible in both of them; but, while in the first special case the $Q$-energy density then remains positive, in the second one we find it negative.Comment: 25 pages, to be published in Gen. Rel. Grav. 200