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The article covers a system of self-adaptable automatic adjustment for elastically deformable packing blocks in mass-exchange apparatuses based on the identification of inertial component peaks in the structure of the filtration flow through the layers of elastically deformable packing materials. It shows the possibilities for the use of wastes from metal-building enterprises formed during machine processing of stainless alloyed steels as packing materials in elastically deformable blocks of mass-exchange apparatuses. The article also describes the automatic control system for hydraulic and mechanic modes by means of stepwise volumetric deformation of the blocks with packing materials.

The paper presents the scheme and algorithm of automatic adjustment of process parameters for elastically deformed blocks of packing materials in mass exchange apparatuses by the turbulization index that indicates fluid dynamics bursts of the inertial compound in the structure of the filtration flow and is an instrument for automatic adjustment of flow dynamic modes of developed turbulization and emulsification in elastically deformed packing blocks at the commissioning stage. The article describes main features and prospects of use of industrial wastes from metal-working plants as packing materials in elastically deformable contact blocks in mass exchanges apparatuses.

The effect ionizing radiation and hypomagnetic conditions have on the lettuce seeds of Lactuca sativa L is studied on the 120-cm cyclotron at Moscow State University’s Skobeltsyn Institute of Nuclear Physics. The seeds are irradiated with deuterons having an energy of ~13.7 MeV at doses of 65 Gy, 0.55, and 5.5 kGy. They are then germinated under conditions of a geomagnetic field weakened by 50 and 103 times. The change in the response of seeds to radiation exposure depending on the attenuation of the geomagnetic field is analyzed.

The impurity composition of multi-sector plates of nitrogen and boron-containing synthetic HPHT diamonds has been investigated by laser-induced breakdown spectroscopy. It is shown that a comparative analysis of the intensities of the characteristic atomic and molecular bands in the plasma emission spectrum during laser-induced modification of the surface of the samples makes it possible to distinguish both the type of diamond and the crystallographic orientation of the analyzed sector of the sample.

A compact laser system based on a Nd:YAG laser with self-phase conjugation for the remote analysis of substances via laser induced breakdown spectroscopy is proposed. The possibility of creating a reliable system for the remote diagnostics of materials in real time is demonstrated.

Alongside the development of methods of intensifying convective heat transfer inside the blade, development of methods of local improvement of the efficiency of film cooling of the blades surface is still of immediate interest. The film is formed on the blade surface in conditions of high-camber shape and low initial velocity of the gas flow in the vicinity of the leading edge with its subsequent abrupt acceleration. The paper presents some data on the peculiarities of film formation on the back and pressure side of the blade in the vicinity of the leading edge. Experimental temperature distribution over the adiabatic wall was obtained with the use of a FLIR-E 64501 thermal imager. It was found that the conditions for the film formation on the blade back are more favorable than those on the pressure side. It manifests itself in the fact that optimal blowing parameters on the blade back are considerably lower than those on the pressure side. The use of V-shaped dimples located on the wall immediately behind the holes for blowing was suggested as a measure for local improvement of film cooling efficiency. The efficiencies of film cooling in the formation of a curtain, without the use and with the use of V-shaped dimples behind the holes for blowing were compared. Local improvement of efficiency and uniformity of film cooling distribution with the use of V-shaped dimples behind the holes for blowing was observed.

The microstructures of a commercial aluminum foil and an aluminum foil alloyed by 0.001 wt % scandium are studied before and after electrochemical etching. The strength properties, the capacitance, and the weldability of the foils subjected to electrochemical etching are investigated. We are the first to show that the alloying of aluminum by such a low amount of scandium affects the microstructure of a foil and is sufficient for increasing the strength properties, the capacitance, and the weldability of the aluminum foil used for capacitors.

The electron lens in the Fermilab Integrable Optics Test Accelerator (IOTA) will enable new research in nonlinear integrable optics, space-charge compensation, electron cooling, and the stability of intense beams. This research addresses scientific questions on high-brightness beams and operational challenges of high-power accelerators for nuclear and particle physics. We review the roles that electron lenses play in this field and the physical principles behind their applications. The design criteria and specifications for the IOTA storage ring and electron lens are then discussed. We conclude with a description of the components of the apparatus.

The study of multi-sector plates of nitrogen- and boron-containing synthetic HPHT diamonds by laser- induced breakdown spectroscopy was carried out on a real-time basis. The obtained data were analyzed and compared with the data during scanning of the samples with the data of local measurements in the corresponding sectors of the crystals. Measurements and analysis of plasma emission spectrum in real time into account the process of laser-induced modification of the surface of the samples, makes it possible to distinguish both the type of diamond as well as the crystallographic orientation of the analyzed sector of the sample. It was found that in terms of the streaming measurement of plasma spectrum, a more careful selection of the modes of interaction of laser radiation with the surface of the samples is needed, which, in particular, affects the capabilities of the method in terms of spatial resolution.

The article describes approaches to creating a laser system that generates radiation simultaneously at two wavelengths, both in the infrared and ultraviolet range. The laser system is based on a pulsed Nd: YAG laser with self-phase conjugation. The generation of synchronized pulses at wavelengths of 1064 and 355 nm is a distinctive feature of the laser system. Ultraviolet pulses are part of the converted fundamental radiation into the third harmonic. Also, energy impulses are equal. The problem is considered in the direction of remote measurements using laser-induced breakdown spectroscopy.

An amplifier based on a highly-doped chromium zinc-selenide (Cr:ZnSe) crystal is proposed to increase the pulse energy emitted by an electron bunch after it passes through an undulator magnet. The primary motivation is a possible use of the amplified undulator radiation emitted by a beam circulating in a particle accelerator storage ring to increase the particle beam’s phase-space density—a technique dubbed optical stochastic cooling (OSC). This paper uses a simple four energy level model to estimate the single-pass gain of Cr:ZnSe and presents numerical calculations combined with wave-optics simulations of undulator radiation to estimate the expected properties of the amplified undulator wave-packet.

An overview of radiophysical investigations of the lunar soil and plasma shell by active radar detection with the use of spacecraft is presented. The possibility is analyzed of conducting bistatic measurements using the Irkutsk Incoherent Scattering Radar and the onboard radar system RLK-L which is being developed for the orbital station of the Luna-Resurs mission.

Nodular dermatitis, (dermatitis nodularis), is an exotic for the Russian Federation poxviral disease. Some epizootical characteristics of it, problems of laboratory diagnostics, and possible reasons of extension of agent spread areal are discussed in this review. Phylogenetic analysis of P32 gene nucleotide sequences of dermatitis nodularis virus has also been conducted. It is noted that taking into account the economic loss caused by the disease and possibility of its import into non-enzootic regions, it is necessary to use existing effective means of specific prophylacsis extensively. The swift outspread of the disease in the Russian Federation should be considered as the risk factor for biological safety of our country.

Optical stochastic cooling (OSC) is expected to enable fast cooling of dense particle beams. Transition from microwave to optical frequencies enables an achievement of stochastic cooling rates which are orders of magnitude higher than ones achievable with the classical microwave based stochastic cooling systems. A subsytem critical to the OSC scheme is the focusing optics used to image radiation from the upstream "pickup" undulator to the downstream "kicker" undulator. In this paper, we present simulation results using wave-optics calculation carried out with the {\sc Synchrotron Radiation Workshop} (SRW). Our simulations are performed in support to a proof-of-principle experiment planned at the Integrable Optics Test Accelerator (IOTA) at Fermilab. The calculations provide an estimate of the energy kick received by a 100-MeV electron as it propagates in the kicker undulator and interacts with the electromagnetic pulse it radiated at an earlier time while traveling through the pickup undulator., 4 pages, 4 figures, submitted to NIMA (Proceedings of the EAAC17 workshop)

A compact laser system based on a Nd:YAG laser with self-phase conjugation for remote analysis of substances by laser-induced breakdown spectroscopy at a distance of not less than 10 m is proposed.

The results of neutron studies of the metal nanostructure of anticorrosive cladding for vessels of WWER -1000 nuclear reactors under different conditions of additional tempering are presented. In the anticorrosive-cladding material, small structural components (inhomogeneities) with a correlation radius of 2–3 nm are observed which form fractal structures with a scale of more than 100 nm. It is shown that at different annealing temperature, these small objects create new structures at crystal boundaries in the form of defect surfaces with the fractal dimension D s = 2.4–2.6. In samples of anticorrosive cladding, nonmagnetic austenitic γ-phase iron (γ-Fe) and magnetic δ-ferrite (α-Fe) are observed. The alloy is found to be magnetically hard.

The precise and express analysis of nanocarbon materials chemistry continues to be one of the key tasks in the study and the application of these unique structures. Despite the large variety of analytical techniques that have been commonly used for this purpose, the development of new methods that will further expand the efficiency of nanocarbon material characterization is still needed. Herein, the applicability of laser-induced breakdown spectroscopy (LIBS) towards studying the chemical composition of different types of nanocarbon structures was investigated. Graphene oxide, reduced graphene oxide (analogous of pristine graphene) and detonation nanodiamonds were chosen as the most attractive representatives of nanocarbon materials. The as-obtained results demonstrate that the functionalization parameters, such as the functionalization degree and predominant type of the functional groups, can be effectively determined on the basis of the analyzed plasma emission spectra. Furthermore, the presence of various inorganic contaminants can be identified using the LIBS technique. When compared to conventional approaches that study samples in the form of thick pellets, thin films of nanocarbon structures on various substrates were successfully analyzed using the LIBS technique. Several experimental features arise in this case, in particular, the possible ablation of wafer and formation of a thermal emission background. To overcome these challenges and to obtain reliable informative spectra, adjustment of the ablation parameters and additional spectra processing procedures were applied. As a result, the LIBS method can be a valuable and simple tool for quality control and the characterization of various nanocarbon structures.

The article presents experimental data on the formation of film cooling on the suctions and pressure sides of a turbine blade near its leading edge under conditions of flow acceleration and wall curvature using V-shaped grooves behind the injection holes. It is shown that to achieve acceptable values of the efficiency of film cooling when using V-shaped grooves on the wall, a lower relative flow rate of the cooler can be used. The results can be used in the design of effective cooling systems for turbine blades.

We investigate the possibility of using the method of laser-induced breakdown spectroscopy to identify diamonds and detect changes in atomic bonds in crystals due to the presence of impurities or due to changes in the hybridisation state of carbon atoms. It is found that laser-induced graphitisation of the diamond surface leads to a significant increase in the sensitivity of the method.

Studies of phenomena accompanying the interaction of superstrong electromagnetic fields with matter, in particular, the generation of an electron–positron plasma, acceleration of electrons and ions, and the generation of hard electromagnetic radiation are briefly reviewed. The possibility of using thin films to initiate quantum electrodynamics cascades in the field of converging laser pulses is analyzed. A model is developed to describe the formation of a plasma cavity behind a laser pulse in the transversely inhomogeneous plasma and the generation of betatron radiation by electrons accelerated in this cavity. Features of the generation of gamma radiation, as well as the effect of quantum electrodynamics effects on the acceleration of ions, at the interaction of intense laser pulses with solid targets are studied.

A concept of a highly-efficient high-power magnetron transmitter allowing wide-band phase and the mid-frequency power control at the frequency of the locking signal is proposed. The proposal is aimed for powering Superconducting RF (SRF) cavities of intensity-frontier accelerators. The transmitter is intended to operate with phase and amplitude control feedback loops allowing suppression of microphonics and beam loading in the SRF cavities. The concept utilizes injection-locked magnetrons controlled in phase by the locking signal supplied by a feedback system. The injection-locking signal pre-excites the magnetron and allows its operation below the critical voltage in free run. This realizes control of the magnetron power in an extended range (up to 10 dB) by control of the magnetron current. Experimental studies were carried out with 2.45 GHz, 1 kW, CW magnetrons. They demonstrated stable operation of the magnetrons and the required range of power control at a low noise level. An analysis of the kinetics of the drifting charge within the framework of the presented model of phase focusing in magnetrons substantiates the concept and the experimental results.

The change in the functional properties of positive photoresists during their storage is a serious issue in photolithography. The recovery of the functional properties of photoresists, and especially, the quality of the edge of the formed elements and changes in their sizes compared to the sizes in the photostencil, is possible by the introduction of additives into the composition of positive photoresists which form hydrogen bonds with the novolak resins constituting them prior to their usage. Experimental verification of the correlation between the density of the hydrogen bonds and the photoresist resolution has been obtained.

The impact of ionizing radiation and hypomagnetic conditions on seeds of the lettuce Lactuca sativa L. is studied on the 120-cm cyclotron at the Skobeltsyn Institute of Nuclear Physics. The seeds are irradiated with α-particles with energies of around 25.8 MeV and placed to germinate in a hypomagnetic chamber under conditions of an attenuated (up to 2500 times) geomagnetic field. Chromosomal aberrations in the first mitosis of the root meristem are analyzed. Changes in the irradiated samples are observed when compared to control samples. Hypomagnetic conditions greatly magnify the negative impact of ionizing radiation.

Modern CW or pulsed superconducting accelerators of megawatt beams require efficient RF sources controllable in phase and power. Typically, the costs of the RF sources and their operation are a significant part of the total cost for large-scale projects. The efficiency of the traditional RF sources (klystrons, IOTs, solid-state amplifiers) is lower in comparison to magnetrons and the cost of RF power per Watt is significantly higher. Therefore the magnetron-based controlled in phase and power RF sources could significantly reduce the capital and operation costs of ADS and SNS like projects or, e.g., the Electron-Ion Collider projects unlike the traditional RF sources. Currently, a number of works suggests the use of magnetrons controlled by a resonant injected (injection-locking) RF signal instead of traditional RF sources. We developed a new approach to controlling magnetrons for superconducting accelerators with megawatts beams In the presented work we describe an innovative technique producing the “stimulated” RF generation of magnetrons powered below the self-excitation threshold voltage. This was predicted and substantiated by a recently developed kinetic (electrodynamic) model of magnetron operation. The technique allowing operation in CW and pulse modes has been experimentally verified and studied. It allows stable, controllable in phase and power operation of magnetrons providing efficiency higher than other types of RF power sources. The technique does not require high voltage pulse modulators for a pulsed RF generation. It also looks to be a promising opportunity to improve magnetron reliability and extend life time. Measured characteristics of the developed technique, its experimental verification and verification of the kinetic model briefly presented in the text are discussed in our work.

For the first time CW laser oscillation on Er-Yb doped PTR glass with diode pumping is demonstrated. For the monolithic laser the maximum output power of 0.47W at wavelength of laser oscillation of 1574 nm and a slope efficiency of 6% was achieved.

We demonstrated that functionalization parameters and presence of inorganic contaminants can be effectively determined by the use of LIBS method. Considering simplicity and versatility of this technique, LIBS method can be regarded as an effective approach for study of nanocarbon materials.

The production of metal ion beams by electron cyclotron resonance (ECR) ion sources using the MIVOC (Metal Ions from Volatile Compounds) method is described. The method is based on the use of metal compounds which have high vapor pressure at room temperature, e.g., C2B10H12, Fe(C5H5)2, etc. Intense ion beams of B and Fe were produced using this method at the FLNR JINR cyclotrons. Experiments on the production of cobalt, chromium, vanadium, germanium, and hafnium ion beams were performed at the test bench of ECR ion sources. Main efforts were put into production and acceleration of 50Ti ion beams at the U-400 cyclotron. The experiments on the production of 50Ti ion beams were performed at the test bench using natural and enriched compounds of titanium (CH3)5C5Ti(CH3)3. In these experiments, 80 μA 48Ti5+ and 70 μA 48Ti11+ beam currents were obtained at different settings of the source. Following successful tests, two 3-week runs were performed with 50Ti beams at the U-400 cyclotron aimed to perform experiments on the spectroscopy of superheavy elements. The intensity of the injected 50Ti5+ beam was 50–60 μA. The source worked stably during experiments. The compound consumption rate was determined at about 2.4 mg/h, which corresponded to the 50Ti consumption of 0.6 mg/h.

A paradigm has been developed according to which an additional FM signal transfer channel is formed in a standard optical fiber transmission line without violating the main AM channel operation. Using the proposed approach, an RS-232 interface signal has been experimentally transferred via a standard intraobject 100-Mbit Ethernet line based on an SMF-28 single-mode optical fiber.

The study of the generation characteristics of Nd:YAG lasers with multiloop self-organizing phase conjugate cavities using a passive Q-switch based on a Cr:YAG crystal is carried out. It is shown that Q-switching of the phase conjugate cavity is caused not only by absorption saturation of the passive Q-switch, but also by modulation of diffraction efficiency of holographic saturable gain gratings in the Nd:YAG active laser medium.

An experimental setup for studying the reaction d + d → 2He + 2 n is described, and the first preliminary results of measurements at a deuteron energy of 15 MeV are presented. The experiment was aimed at determining the energies of quasibound singlet states of two-nucleon systems (nn and pp), these energies being important features of nucleon–nucleon (NN) interaction. The measurements in question were performed at a deuteron beamfrom the U-120 cyclotron of the Skobeltsyn Institute ofNuclear Physics (Moscow State University). Two protons and one of the neutrons fromthe breakup of the dineutron system were detected in the experiment. A simulation of the reaction in question and preliminary experimental results reveal the possibility of determining the energy of quasibound singlet states on the basis of the form of the energy spectra of particles originating from their breakup.

A method to increase the transmission efficiency of an analog fiber-optic line using a shift of the working point of an external modulator toward minimum transmission is proposed. The method is based on an increase in the signal contrast owing to the suppression of the constant component and the application of an erbium-fiber amplifier in the near-saturation mode. An increase in the transmission (up to 5 dB) in comparison with the transmission corresponding to the quadrature working point is demonstrated. An increase in the nonlinear distortion factor due to the shift of the modulator from the quadrature working point is analyzed. An increase in the nonlinear distortions under the conditions for the maximum transmission is no greater than 0.5%. A theoretical model is developed to describe the experimental effects. The theoretical results are in good agreement with the experimental data.

We report on the results of studying quasi-two-dimensional nanostructures synthesized here in the form of semiconducting CdSe nanoplatelets with a characteristic longitudinal size of 20–70 nm and a thick-ness of a few atomic layers. Their morphology is studied using TEM and AFM and X-ray diffraction analysis; the crystal structure and sizes are determined. At room and cryogenic temperatures, the spectra and kinetics of the photoluminescence of such structures (quantum wells) are investigated. A hybrid light-emitting diode operating on the basis of CdSe nanoplatelets as a plane active element (emitter) is developed using the organic materials TAZ and TPD to form electron and hole transport layers, respectively. The spectral and current-voltage characteristics of the constructed device with a radiation wavelength λ = 515 nm are obtained. The device triggering voltage is 5.5 V (visible glow). The use of quasi-two-dimensional structures of this type is promising for hybrid light-emitting diodes with pure color and low operating voltages.

The generation regimes in a pulsed Nd:YAG laser with transverse LED pumping and multiloop self-pumped phase-conjugate cavity on the gain gratings are studied. The differential efficiency of laser is 27% in the free-running regime at a pulse energy of up to 1 J and quality parameter M 2 of no greater than 1.5. The pulse energy under passive Q-switching is no less than 60% of the pulse energy in the free-running regime at the same beam quality. The generation of the narrow-band radiation is demonstrated. A generation band of no greater than 1.2 GHz corresponds to the primary single-frequency high-power laser pulse in the free-running mode under conditions for self-Q-switching on the gain gratings. When additional elements (F 2 − :LiF and Cr4+:YAG crystals) are introduced in the optical scheme of the phase-conjugate cavity, similar narrowband single-mode generation is observed in the passive Q-switching regime as a pulse train or monopulse. The laser pulse power is up to 2 MW at a pulse duration of 20 ns.

Middle-East respiratory syndrome is a human disease caused by a new coronavirus. In December, 2012 WHO published draft regulatory document on diagnostics of the virus. It was recommended to use two methods of disease diagnostics - two-phase reverse-transcription real-time PCR and enzyme immunoassay. The first phase of the PCR-diagnostics should include reverse-transcription real-time PCR targeted on the genome fragment upwards of upE. The second (control) PCR-test may be alternatively targeted within the bonds of the genome, its target being non-crisscross with upE gene. It should include sequencing of, at least, a segment of one of the viral genomes and comparative analysis of the obtained sequence along with the like ones deposited in the GenBank. Enzyme immunoassay is retrospectively used for virus-specific antibody detection in convalescents’ blood sera. Examined are the key specifications of the methods for the detection of ethiological agent or specific antibodies to it, and WHO methodological recommendations in case of Middle-East respiratory syndrome diagnostics.

A laser adhesiometer is developed to determine the adhesive and cohesive forces in multilayer materials. The obtained experimental dependences are explained using the laser microexplosion model. The advantages of determining the adhesive and cohesive forces using the laser adhesiometer over other methods are grounded.

The effect of α-particles on one of the simplest unicellular organisms, Synechocystis sp. PCC 6803 cyanobacteria, is studied using a 120-cm cyclotron. Suspensions of cells are irradiated in a cuvette with walls made of thin mylar films. The energy of α-particles in the solution is 24 MeV. The linear energy transfer (LET) of α-particles is close to that of relativistic nuclei of the neon-magnesium group in galactic cosmic rays, making it possible to simulate their effect on biological objects. A number of apparent changes in the Synechocystis spectral characteristics are found for samples irradiated in and outside a hypomagnetic field.

The article is devoted to the issue of thermodynamic optimization of an oil refinery. Optimization is carried out by the exergy method of thermodynamic analysis, which allows you to take into account the quantitative as well as qualitative characteristics of thermal processes. The research uses the principles and rules of pinch analysis. Thus, the article discusses the task of optimizing oil refining processes using the pinch analysis method using exergy. The objective of the article is to increase energy efficiency by reducing exergy losses in technological processes of oil refining. The results of the study allow us to determine exergetic losses and propose measures to reduce them.

Previously reported preparation method for Pd-based intermetallic targets (Usoltsev, et al., 2012) [1] has been successfully applied for producing two stationary 243Am/Pd targets. Both targets have been irradiated at the U-400 cyclotron at Flerov Laboratory of Nuclear Reactions Dubna (Russian Federation) using high intensity beams (up to 0.83 μApart) of 48Ca18+. Alpha-particle spectroscopy and light microscopy allowed for a comprehensive characterization of the intermetallic targets before and after irradiation. A natNd/Pd intermetallic target and a solely electroplated 243Am/Ti target were similarly investigated for comparison.

Space radio emission is the important source of background for radio physical investigation of the ionosphere. Variations of the background signal and scintillations of the discrete radio sources allow defining some ionosphere characteristics such as plasma density variations and degree of plasma inhomogeneity. Irkutsk incoherent scatter radar (IISR) has narrow palm-like directivity diagram. With this diagram IISR scans a wide sector of elevation angles of the celestial sphere. The sweeping time of a 40° sector with 0.5° step is around several seconds. Therefore, IISR in the passive mode is capable to work as an imaging riometer. As a result of several month passive mode observations we detected a number of scintillation events and found a good agreement between the scintillation and spread-F events which were observed independently. IISR in the passive mode is also sensitive to the solar events and probably capable to observe solar radio emission objects with good time resolution and in a wide spatial range.

Using the Irkutsk Incoherent Scattering Radar, it is demonstrated that the high sensitivity of such radars, which are usually used for studies of the Earth’s ionosphere, also enables their use in a passive mode for observations of astronomical radio sources. Observations of solar flares accompanied by coronal mass ejections and of quasi-stationary radio sources on the Sun have been carried out. In addition, scintillations of several of the brightest discrete radio sources (Cygnus A, Cassiopeia A, and the Crab Nebula) have been studied over several months. These data can also be useful for studies of the ionosphere and interplanetary space.

Several configurations of the laser self-pumped phase-conjugate cavities with multiwave mixing directly in the laser medium based on a single Nd:YAG laser element pumped by multikilowatt laser diode 2D stacks are experimentally studied and compared. In the laser configurations with six- and eight-wave mixing there are generated a high-intensive self-Q-switched 200-ns laser pulse followed by low-intensive free-running lasing. An increase of the number of waves taking part in multiwave mixing from six to eight leads to increase in the laser maximum output energy and optical-to-optical efficiency from 0.55 up to 1.1 J and from 8.3 up to 18% respectively. In the laser configuration with ten-wave mixing the energy characteristic is similar to the same in the laser configuration with eight-wave mixing, but the temporal and spectral characteristics are different from the same in the laser configurations with six- and eight-wave mixing. In last laser configuration not only the first pulse, but also all the train of pulses is generated in high-intensive TEM00 diffraction-limited (M 2 = 1.3---1.5) single-frequency self-Q-switched mode via writing and erasing the gain gratings by the intracavity radiation.

The results of an experimental study of organic light-emitting diodes (LEDs) with luminescent layers based on two types of CdSe/CdS semiconductor quantum dots (QDs) with an average CdSe core diameter of 3 and 5 nm and a characteristic CdS shell thickness of 0.5 nm are presented. The dependences of the LED efficiency on the QD concentration are determined. The experimental data are used to determine the mechanism of electronic-excitation transfer from the organic matrix to the semiconductor QDs. Ways of optimizing the design of the LEDs in order to improve their efficiency are suggested on this basis.

The setup under development is intended to serve as the Russian National Primary Special Standard for Laser Pulse Duration in the range from 10 to 1000 ps. The core components of the standard are a streak camera with picosecond temporal resolution and a Fabry-Perot etalon illuminated by femtosecond laser pulses. The etalon defines a time interval which is used to calibrate the temporal scale of the streak camera. The standard includes a picosecond laser pulse generator for reproduction and transfer of the unit of laser pulse duration to another measuring instrument or secondary standard. Described are the principles of operation, the construction of the standard, and the results of preliminary experiments to determine its metrological properties.