Studying the long-time variability of the Seyfert 2 galaxy NGC 4388 with INTEGRAL and Swift

We present analysis results on the Seyfert 2 galaxy NGC 4388 based on 6 yr of INTEGRAL data combined with Swift/Burst Alert Telescope survey and Swift/X-Ray Telescope pointed observations. These data, taken from 2003 to 2009, allow us to study the broad-band properties of this active galactic nucleus in the 0.3-300 keV energy range. The continuum emission of NGC 4388 is well represented by an absorbed power-law model with exponential cut-off at high energies and an upper limit on the reflection component of R < 0.5. We find slow strong variations of the hard X-ray emission, indicating both flux and spectral slope changes on the 3-6 months time-scale. In comparison with previous results on NGC 4388, the source shows a complex variability behaviour, i.e. the spectral shape and the 20-60 keV flux vary independentl

The study of spectral and luminescent properties of humic acids and their impact on the photodegradation process of 2,6-bis(hydroxymethyl)-4-methylphenol

UV photolysis (KrCl excilamp, λ rad ~ 222 nm) of aqueous humic acids (HAs) samples was carried out without and in the presence of 2,6-bis(hydroxymethyl)-4-methylphenol. The samples of HAs fractions were obtained from Aldrich Chemical Co and prepared from peat of Arkhangelsk region. The presence of Aldrich humic acid in the solution has a essential effect on the processes of phenolic compound photochemical degradation under the action of light from the excilam

Femtosecond Alexandrite Laser with InP/InGaP Quantum-Dot Saturable Absorber

A semiconductor saturable absorber mirror (SESAM) passively mode-locked Alexandrite laser was demonstrated. Using an InP/InGaP quantum-dot saturable absorber mirror, pulse duration of 380 fs at 775 nm was obtained. The laser was pumped at 532 nm and generated 295 mW of average output power in mode-locked regime with a pump power of 7.3 W. To the best of our knowledge, this is the first report of a passively mode-locked Alexandrite laser using SESAM in general and quantum-dot SESAM in particular

Femtosecond Alexandrite Laser with InP/InGaP Quantum-Dot Saturable Absorber

A semiconductor saturable absorber mirror (SESAM) passively mode-locked Alexandrite laser was demonstrated. Using an InP/InGaP quantum-dot saturable absorber mirror, pulse duration of 380 fs at 775 nm was obtained. The laser was pumped at 532 nm and generated 295 mW of average output power in mode-locked regime with a pump power of 7.3 W. To the best of our knowledge, this is the first report of a passively mode-locked Alexandrite laser using SESAM in general and quantum-dot SESAM in particular

Current State of Pasture Vegetation of the Arid Zone (On the Example of Key Rural Municipalities of the Republic of Kalmykia)

The article presents the results of field observations over 2012–2018 carried out by the Department of Environmental Research of the Institute for Complex Studies of Arid Territories. The work includes materials on the climatic review and the original results of geobotanical investigation of 5 farms in rural municipalities of the Republic of Kalmykia (RK) over the period of the study. We used materials of a large geobotanical survey of YUZHNIIGIPROZEM Company (1991–1995) and materials of earth remote sensing (by Landsat satellite). According to the studies, the period from 2012 to 2018 demonstrates a general trend of climate warming throughout the territory of Kalmykia accompanied by a decrease in precipitation and an increase in extreme droughts in the summer. Geoecological monitoring of pastures at five key sites of the RK revealed that in the dry steppe zone (Manych municipality) and in the semi-desert zone (Khanatinsky municipality), deterioration of pastures is observed; in the desert zone (Adykovskoye municipality), significant degradation processes were identified associated with strong anthropogenic impact and fires, manifested in the loss of valuable food crops (wormwood) and increased influence of cereal crops. Floristic and phytocenotic analyzes revealed an increase in the number of plant species in the weed and ruderal groups

From a forecasting methodology for the electric energy consumption of mono-towns to its sustainability

The need of Russia for a resource-innovative energy strategy for the period up to 2035 makes it urgent to create a methodology of strategic forecasting for the electric energy consumption of mono-towns, which will result in the efficient development of a power supply system, ensuring territories’ sustainability. For this purpose, it is necessary to consider a mono-town as a complete system, a living organism with a definite life cycle and structure of energy consumers. The authors offer a technocoenosis approach to carry out the ranking and structural analysis of the electric energy consumption of one of the Sverdlovsk region’s mono-towns, taking into account dynamics in population, enterprises, organizations and institutions for the period of 5 years. The provided analysis makes it possible to judge the technocoenosis optimality using characteristic exponent β, depending on the structural features of the territory. The authors developed an algorithm for electric energy consumption forecasting, based on Support Vector Machines (SVM), which takes into account the electric energy of mono-towns’ consumers and the climatic factors. Forecasting accuracy was achieved using cross-validation of the input data in order to optimize the training model. The corresponding changes in electric energy consumption, when a characteristic exponent is optimal, will result in a target forecast that provides the sustainable development of mono-towns. © 2014 WIT Press.International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen