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DQE and eDQE were evaluated for a slot scan X-ray system using four standard radiation qualities: RQA3, RQA5, RQA7, and RQA9. The results showed that the system under consideration, KARS-BKS2 fluorograph, provided maximal DQE(u,v) and eDQE(u′,v′) in the case of radiation quality RQA5 and a small focal point. At null spatial frequencies DQE(0) was greater than 40% and eDQE(0) was 35%.

Мета. Провести порівняльні випробування ґрунтообробної установки в виробничих умовах, з вивченням якісних показників роботи при вирощуванні цукрових буряків. Методи. Визначення коефіцієнта структурності ґрунту, гербологічного моніторингу бур’янів, фенологічні спостереження. Результати. В результаті обробітку ґрунтообробною розрихлювально-сепаруючою установкою відбу-вається розшарування ґрунту на чотири підшари: наднасіннєвого, насіннєвого, піднасіннєвого і підорного. З наднасіннєвого підшару повністю видалені окремі брила ґрунту розміром більше 20 мм. У насіннєвому підшарі утворюється найбільш цінна в агрономічному відношенні структура ґрунту, розмір якої не перевищує 3-х кратний розмір насіння, щільність складання піднасіннєвого підшару не перевищує 1,25 г/см3. Підорний підшар не має щільності більше 1,3 г/см3 і твердості у плужній підошві більше 3 МПа, що забезпечується основним обробітком. Визначено, що відома машина для оптимізації агрофізичних властивостей орного шару ґрунту дозволяє, в порівнянні з традиційними культиваторами, підвищити коефіцієнт структурності приблизно в 2,5 рази. Актуальність полягає в тому, що обробіток ґрунту з використанням ґрунтообробної розрихлювально-сепаруючої установки дозволить вдосконалити методи передпосівного обробітку ґрунту для поліпшення його агротехнічних якостей, виключивши такі технологічні операції як боронування і культивацію та зробити підготовку ґрунту до сівби за один прохід. Висновки. Використання експериментальної розрихлювально-сепаруючої установки для передпосівної підготовки ґрунту при вирощуванні цукрових буряків в порівнянні з традиційними знаряддями за рахунок поліпшення якості обробки ґрунту дозволяє отримати сходи раніше на 3–4 дні, забезпечити краще збереження в ґрунті вологи (на 3–4%), істотно знизити засміченість посівів і підвищити врожайність. Причому дослідження показали, що протягом усього вегетаційного розвитку рослин агрофізичні параметри оброблюваного шару ґрунту зберігали відносну стабільність.

International audience; The theory of photoionization describing the interaction of x-ray free-electron laser (XFEL) pulses and high-harmonic-generated (HHG) radiation is generalized to ultrashort laser pulses, where the concept of the standard ionization probability per unit time in Fermi’s golden rule and in Einstein’s theory breaks down. Numerical calculations carried out in terms of a generalized photoionization probability for the total duration of pulses in the near-threshold regime demonstrate essentially nonlinear behavior, while absolute values may change by orders of magnitude for typical XFEL and HHG pulses. XFEL self-amplified spontaneous emission pulses are analyzed to reveal general features of photoionization for random and regular spikes: the dependences of the nonlinear photoionization probability on carrier frequency and spike duration are very similar, allowing an analytical expectation value approach that is valid even when there is only limited knowledge of random and regular parameters. Numerical simulations carried out for typical parameters demonstrate excellent agreement.

In the work, the comparison of sensitivities of optical plasmon sensors constructed on the basis of semiconductor nanoparticles of various shapes is presented. The calculation was made within the framework of the dipole approximation. A characteristic of sensitivity is the value of the shift of the plasmon resonance maximum per unit change in the refractive index of a medium. The influence of the material of a nanoparticle and its shape on the sensitivity of an optical plasmon sensor is shown.

At present, almost all areas of human activities involve the use of nanoparticles for solving various technical issues [1-6]...

We report the spark discharge synthesis of aerosol germanium nanoparticles followed by sintering in a tube furnace at different temperatures varying from 25 to 800 &deg, C. The size, structure, chemical composition and optical properties were studied. We have demonstrated a melting mechanism of nanoparticles agglomerates, the growth of the mean primary particle size from 7 to 51 nm and the reduction of the size of agglomerates with a temperature increase. According to transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) data, primary nanoparticles sintered at temperatures from 25 to 475 &deg, C basically have a structure of Ge crystals embedded in a GeOx amorphous matrix, as well as visible photoluminescence (PL) with the maximum at 550 nm. Pure germanium nanoparticles are prepared at temperatures above 625 &deg, C and distinguished by their absence of visible PL. The shape of the experimental UV-vis-NIR extinction spectra significantly depends on the size distribution of the germanium crystals. This fact was confirmed by simulations according to Mie theory for obtained ensembles of germanium nanoparticles.

We investigated theoretically the time dependence of ultra-short laser pulse scattering by an atom at the high-frequency limit for the spectral and total probability of the process using new expression which we derived in this paper. We established that the time dependence of spectral scattering is presented by the curve with the maximum for sufficiently large detuning of scattering frequency from the carrier frequency of the pulse, while the total scattering probability is always the monotonically increasing function of time. We also studied the dependence of scattering probability on pulse duration at the long-time limit. It was shown that, at the long-pulse limit, the scattering probability is a linear function of pulse duration, while in the opposite case, it is a function with maximum. The position of this maximum is determined by the detuning of the scattering frequency from the carrier frequency of the pulse.

Мета. Провести дослідження в польових умовах робочого органу у вигляді троса на роторній ґрунтообробній розрихлювально-сепаруючій установці, що підвищує якість обробітку ґрунту та дозволяє контролювати ріст бур’янів. Методи. Визначення коефіцієнта структурності ґрунту, гербологічного моніторинигу бур’янів. Результати. У польових умовах експериментально визначено, що використання гнучкого робочого органу сприяє підрізанню пласта ґрунту, його кришінню в залежності від стану і різновиду. Встановлено, що при зміні швидкості руху установки в нижньому шарі ґрунту спостерігаються незначні середні зміни коефіцієнта структурності ґрунту в порівнянні з контролем. Збільшення швидкості руху експериментальної установки призводить до зменшення коефіцієнта структурності в верхньому і нижньому шарах. Зниження коефіцієнта структурності зі збільшенням глибини обробітку при роботі машини з гнучким елементом пояснюється тим, що при глибині обробітку 0,03 м відбувається вирівнювання поверхні поля, що сприяє збільшенню коефіцієнта структурності. Дослідження впливу використання експериментальної ґрунтообробної установки на засміченість посівів буряку столового показало, зниження загальної засміченості посівів за дворазового обробітку з повтором через 35 днів з використанням гнучкого елементу, яка досягла перед збиранням 95,7%, що на 29% перевищує даний показник, досягнутий без застосування гнучкого робочого органу. Загибель дводольних бур’янів становила 98,5% перед збиранням, що на 13% перевищує результат, отриманий без використання гнучкого робочого органу Висновки. Наявність гнучкого елемента у вигляді троса у складі робочих органів експериментальної установки позитивно впливає на якісні показники обробітку ґрунту. Експериментально доведено, що наявність гнучкого робочого органу у вигляді троса в експериментальній установці забезпечує більш раціональний перерозподіл агрономічно цінних грудочок ґрунту за глибиною оброблюваного шару в порівнянні з контролем. Використання гнучкого елемента у вигляді троса в складі робочих органів роторної ґрунтообробної розрихлювально-сепаруючої установки, дозволяє ефективно контролювати ріст бур’янів без застосування гербіцидів.

A series of previously undescribed N-aryl-N′-pyridin-2-ylureas were prepared via the reaction of 2-aminopyridines with benzoyl azides and tested in vitro as activators of glucokinase. Statistically significant reductions of glucose levels as compared with controls were demonstrated for several compounds.

The radiation absorption cross section of indium–tin oxide (ITO) semiconductor nanoparticles of various sizes placed in various media is calculated in the region of plasmon resonance. The photoabsorption cross sections calculated within the framework of the Mie theory and in the dipole approximation are compared with each other and with the available experimental data. The limits of applicability of the dipole approximation are determined. The prospects of using these nanoparticles as an active material in optical plasmon sensors are assessed.

Among the many ways of representing and processing space information, polygonal ones are not so often found, although polygons, as geometric means of describing spatial information objects, are very common in wide internet content. In computer games, design, even in fine art and many other applications, the polygonal description of such objects is not only widely present, but also received from developers, both theory and practical implementation, a fairly wide set of mathematical and software tools. In this article, it is proposed to extend some well-proven developments in the analysis and transformation of computer images to real digitized satellite images, as well as to use combinations of satellite processing methods and polygonal methods which are characteristic for virtual reality conditions. In addition, the paper provides approaches for detecting hidden and being hidden artifacts – information bookmarks. The definitions of the main directions of intel-latency are given, as an important property of complex images of the Earth’s surface obtained during space monitoring of problem-oriented territories. A variant of the classification of the types of manifestation of this property is given, as well as its description in the language of soft models.

In this paper, we presented a model, describing transition scattering of ultrashort laser pulses (USLPs) in Maxwellian plasmas in terms of the full spectral-angular probability during the entire time of pulse action. We demonstrated that in the case of the USLP, probability dependence on pulse duration (τ-dependence) generally is a non-monotonic function. The main trends of the τ-dependence were defined. For quasi-elastic transition scattering, we derived analytical formulas of the full spectral-angular probability that describes non-monotonic areas of the τ-dependence with high accuracy. In the framework of the analytical approach, we established conditions, at which non-monotonic trends are realized, and assessed dynamics of local extremes at the variation of problem parameters. We compared τ-dependence, angular dependence of transition, and Thomson scattering probability and assessed limits of analytical approximations. The crucial similarities and differences of these two types of scattering were described.

International audience; On the basis of equations obtained in the framework of second-order quantum-mechanical perturbation theory, the standard approach to the calculation of scattering radiation probability is extended to the case of ultrashort laser pulses. We investigate the mechanism of the appearance of plasmon peaks in the spectrum of the plasma form factor for different parameters of the problem. For the case in which scattering on plasmons dominates over scattering on electron density fluctuations caused by chaotic thermal motion, we derive analytical expressions describing the scattering probability of ultrashort laser pulses on plasmons. Together with this, we obtain a simple expression connecting the frequency of scattered radiation and the energy transmitted from the incident pulse to plasmon, and vice versa. In considering the scattering probability, our emphasis is on the dependence on the pulse duration. We assess in detail the trends of this dependence for various relations between pulse carrier frequency and plasmon energy.

The process of scattering of radiation by indium‒tin oxide (ITO) nanoparticles is theoretically studied at various degrees of doping and for different radii of nanoparticles. Qualitative conclusions are made about the character of the dependence of the scattering cross section on the frequency with variation of the particle size and the percentage content of tin. The prospects of using ITO nanoparticles as an active substance in optical sensors are estimated.

In the work, the physico-mathematical model of an optical plasmon sensor constructed on the basis of semiconductor ellipsoidal nanoparticles is proposed. It is shown that the sensitivity of such a sensor is proportional to the value of the ellipsoid semiaxis along which polarization of acting radiation is directed.

International audience

The standard approach to calculate the Thomson scattering probability is reconsidered for the case of ultrashort incident laser pulses (USLPs). We established a new model for the interaction of USLP with plasmas that is based on Fermi's equivalent photon conception to calculate the spectral-angular differential Thomson scattering probability. The simulations demonstrate that the scattering probability for USLP is a non-monotonic function of pulse duration in contrast to the standard long-pulse model showing linear dependence. An analytical approach is developed to study the nonlinear behavior of the scattering probability as a function of pulse duration and other parameters.

The paper presents the general scheme of operation and the physico-mathematical model of an optical plasmon sensor based on indium-tin oxide (ITO) nanoparticles. The principle of operation of the "ITONPsensor" program intended for simulation of a response of the optical plasmon sensor to a change in parameters of a medium being measured is also described. The program was developed on the basis of the physico-mathematical model of absorption of radiation by semiconductor ITO nanoparticles.

We study the excitation dynamics of Fano resonance within the classical model framework of two linear coupled oscillators. An exact solution for the model with a damped harmonic force is obtained. The details of growth a Fano profile under the harmonic excitation is shown. For incident ultra-wideband pulse, the reaction of a system becomes universal and coincides with the time-dependent response function. The results of numerical calculations clarify two alternative ways for experimental measurement of the complete characteristics of a system: direct observation of the system response to a monochromatic force by frequency scanning or recording of time-dependent response to the delta-pulse. As a specific example, time-dependent excitation in a system consisting of a quantum dot and a metal nanoparticle is calculated. Then it is shown the applicability of the extended model of damped oscillators with radiative correction to describe the build-up a plasmon Fano resonance in a scattering of a femtosecond laser pulse by nanoantenna., 17 pages, 9 figures, 46 References

In this work, the in-situ upgrading of heavy oil from Tatarstan oilfield using steam and copper stearate as a catalyst at 250 °C and 35 bar for 24 hours was studied in stainless-steel reactor. Changes in the density/API gravity, viscosity, chemical composition (SARA-analysis), elemental composition and structure (FTIR-spectroscopy) of heavy oil before and after conversion were determined. Generally, we can summarize, that the content of resins and asphaltenes as well as the average molecular weight of heavy oil were reduced after conversion process. Whereas, amount of saturated and aromatic hydrocarbons was increased due to the destruction of its high molecular weight components. Also, irreversible decrease of viscosity was fixed.

The thickness of aluminum oxide thin films fabricated by technology of atomic layer deposition with different number of cycles measured by small angle X-ray scattering. The dependence of the film thickness in the range of 20–120 nm from the number of ALD process cycles is linear.

The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.

The Mossbauer parameters (the isomer shift δ, the quadrupole splitting ΔE, and the probability of recoilless absorption f') have been analysed for a large number (more than 200) of complexes of mono- and bi-dentate organophosphorus complexes with tetra-alkyltin and alkyltin halides. It is shown that the Mossbauer method can be used to determine the localisation centres of the donor–acceptor bond in complexes of organophosphorus compounds with tin tetrahalides and to determine the geometrical structures of the complexes. It has been observed that the quantities δ, ΔE, and f' for the compounds [R'R''R'''P(Y)]2(1)SnRnX4–n are definitely influenced by the nature of the substituents in the ligand and in the acceptor. This influence can be described with the aid of the reaction constants of the substituents σph and σ*. The bibliography includes 110 references.