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Structural transformations in the external and internal environment of production and economic systems at the present stage affect almost all areas of their activities. They are especially acute in the implementation of innovative processes, due to the key characteristics of their essence. The composition, relations structure, interaction directions and ensuring patterns the possibility and implementation effectiveness of these processes are changing rapidly and significantly. Article describes the role of infrastructure support in the implementation of innovative processes, the implementation of which is necessary to increase the competitiveness of the state in the conditions of the modern world economy. Various interpretations of the concept of innovation infrastructure proposed by domestic and foreign authors are considered. The features of the innovation infrastructure in the modern conditions of a changing and poorly predictable environment are highlighted: network nature, developed information environment, functioning in the conditions of the knowledge economy, in>depth specialization, the use of informal networks of innovative culture. Based on the trends of transformation of the external environment and the subjects themselves, the tasks of developing innovative infrastructure at the regional level are highlighted. The subject of the research in the article is the possibilities of infrastructural support of innovative processes. The results of the study are to identify the importance of the information environment, its structure and functioning features to ensure the effectiveness of the implementation of innovative processes at the present stage. The authors have substantiated various dynamic transformations taking place within the innovation infrastructure and leading to its transformation.

The Crisuri Basin, with its total length of 1093 km (among which 670 km in Romania), is subjected to an effective environmental monitoring system consisting of 18 water stations network. Their integrated information is used for the water assessment problem to understand the biogeochemical processes leading to significant pollution levels in some running water sectors. The goal of this research is to predict the most important factors causing the change of the geochemical measured parameters of some components of the Crisuri water resources. In the present paper, we developed a multivariate statistical model to estimate the spatiotemporal distribution of heavy metals in the field and to identify the contamination sources of Basin River waters. Two methods were deployed as an overall approach to fulfill the proposed objectives, namely the photoneutron activation analysis followed by high-resolution gamma-ray spectrometry and the multivariate statistical analysis. The elements analyzed by different analytical techniques and introduced in databases were As, Cd, Ca, Cu, Fe, Mg, Hg, Na, Ni, Pb, Zn, N-NH4, N-NO2, N-NO3, P-PO4, fixed residues, S-SO4, Cl, phenols and, additional oil compounds. By combining the spatially distributed geochemical data on trace heavy metals with the spatially distributed geophysical data, we obtained the most significant fingerprint factors and their associated uncertainty information concerning the water quality.

Applicative researches in the field of environmental protection like X-ray fluorescence analysis, neutron activation analysis, and other methods, present real increasing importance related to the climate changes that can be observed nowadays. Scientific methods will enter step by step in our life, first of all, due to the accelerated technological development and due to the objective motivations of environmental monitoring necessary to take correct measures for the preservation and protection of nature on the Earth. Determination of some inorganic components, mainly heavy metals, in agricultural crops, is frequently required in health-related environmental studies, due to the high toxicity of trace amounts of such elements for the human organism. The main sources of trace elements to agricrops are their growing media, as soil-water-air ecosystem from which those nutrients are taken up by the root to the foliage. The goal of the present research was to determine the extent to which industrial inorganic pollutants are transferred to the crops. It was achieved by using multielement techniques as photon neutron activation method and X-ray fluorescence methods and statistical modeling in order to determine levels, pathways, and fate of toxic and non-toxic bioactive elements in selected agricrops along with the root soil. Some of the experimental trace metal values exceeded the threshold established by Romanian and EU regulations to protect vegetation and explain the estimated significant crop losses. Multivariate modeling by factor analysis and neural network simulation of the elemental concentration data showed always the component loaded with specific elements coming from industrial emissions. These kinds of studies are very requested regarding the vegetable meant for the human diet.

It is shown that the use of both sides of solar cells created with the heterojunction technology makes possible an increase in the solar-cell efficiency. The difference in illumination of the front and back sides is associated with transformation of the blue part of the spectrum, which is shown by the example of the spectral dispersion of the quantum efficiency. The average difference between the quantum efficiency for both sides is ~11%. The short-circuit current density with the power of the solar spectrum at sea level from 400 to 1100 nm is 36.3 mA/cm2 for the front side and 32.7 mA/cm2 for the back side. The decrease amounts to 9.7%.

“Off-the-shelf” clinical linear electron accelerators (LINAC) have been suggested as alternative to research accelerators once they are no longer suitable for the medical applications. We investigated feasibility of utilising a modified LINAC for instrumental photon activation analysis (IPAA) as a tool in environmental geochemistry studies. The IPAA results were compared with those obtained using a MT-25 research accelerator at Joint Institute for Nuclear Research in Dubna, Russia. To investigate soil pollution in Antalya, Turkey, 90 surface soil samples were analysed and significant enrichments of Ni, Cr and As were found.

This work presents the experimental study of the isomeric ratio of 137mCe–137gCe produced in 138Ce(γ, n) 137m,gCe photonuclear reaction, in neutron capture reaction 136Ce(n, γ) 137m,gCe and in the two simultaneous reactions 138Ce(γ, n) 137m,gCe and 136Ce(n, γ) 137m,gCe in the mixed photon—neutron field by the activation method. The investigated samples were irradiated at the bremsstrahlung photon flux, in the epithermal and thermal-epithermal neutron beam and in the mixed photon-neutron field constructed at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The results were analyzed, discussed and compared with those of other authors to examine the role of the channel effect in nuclear reaction and provide the nuclear data for theoretical model interpretation of nuclear reactions.

Ge 2 Sb 2 Te 5 (GST) material has good potential for integrated optical systems. However, a clear theory describing mechanisms of GST phase state optical switching is still lacking. In this paper, we report investigation of GST ability for reversibly phase state switching under laser pumping. For reversible amophization and crystallization of local regions of the 24 nm GST film with 350 nm diameter we selected nondestructive modes of multiple pulsed laser pumping. Phase states of local regions in the GST film were defined by combination of optical microscopy, atomic force microscopy (AFM) and Raman spectroscopy methods.

We have determined the isomeric ratios of isomeric pairs 97m,gNb, 95m,gNb and 91m,gMo produced in 98Mo(γ, p)97m,gNb, 96Mo(γ, p)95m,gNb and 92Mo(γ, n)91m,gMo photonuclear reactions in the giant dipole resonance (GDR) region by the activation method. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy, neutron configuration, channel effect and direct and pre-equilibrium processes in (γ, p) photonuclear reactions. In this work the isomeric ratios for 97m,gNb from 14 to 19 MeV, for 195m,gNb from14 to 24 MeV except 20 and 23.5 MeV and for 91m,gMo at 14 and 15 MeV are the first time measurements.

The isomeric ratios in 138Ce(γ, n)137m,gCe photonuclear reaction have been measured for energy ranges from 14 to 17, 21 to 23 and at 19 MeV end-point bremsstrahlung energies by the activation method. In order to improve the accuracy of the experimental results, necessary corrections and data analysis were made in the γ-ray activity measurements. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy and the influence of channel effects. The above obtained data are the first time measurements.

The paper reports on the observation of spontaneous fission of nuclides, concentrated in fly ash during the combustion of high-carbon (graphite) material, chemogenic siliceous-carbonaceous rocks and carbonaceous shale in the mixture with brown coal. In the samples obtained, the spontaneous fission was measured by track method. The zones of precipitation of spontaneous fission of nuclides and their lighter homologues on thermochromatographic column were determined. A nuclide with a half-life of 62 days was detected in the alkaline trap. The chemical treatment procedure included co-precipitation with iron hydroxide, dissolution in NH4OH + H2O2 solution and distillation by heating up to 100°C followed by AgI co-precipitation. Based on the chemical behavior it can be concluded that the detected radionuclide belongs to the halides. The content of the parent nuclide in high-carbon (graphite) material and chemogenic siliceous-carbonaceous rock corresponds to 10–14 g/g.

The paper reports on the observation of the spontaneously fissioning nuclides as a result of hydrochemical and high-temperature processing of iron-manganese nodules. The spontaneous fission in the samples obtained was measured by the track method using electrochemical etching, and nuclides with T1/2 = 15 d, T1/2 = 25 d that is similar in chemical properties to Os and T1/2 = 62 d, (similar in chemical properties to Pb and Ra) were detected. The content of the parent nuclide in iron-manganese nodules corresponds to 4 × 10−14−8 × 10−14 g/g.

Several different algorithms to measure physical parameters (especially, current-voltage characteristics) under fixed and variable temperature are presented here. Specifically, these algorithms are intended to achieve the uniform density of experimental data over the used bias voltage interval independent on the measured characteristic representation. Model and experimental data, obtained by using these algorithms are shown. The method of outliers detection during a current- voltage characteristic measurement are shown as well. Application of the adaptive algorithms during scientific experiment allows achieving better results by variation of investigating according to the input data.

In this paper we suggest a model to calculate current-voltage characteristics of double-junction solar cells based on a-Si:H/a-SiC:H. The model considers features of these materials. We simulated I-V dependences of the solar cell as consequent p-i-n structures on the basis of a-Si:H and a-SiC:H. Results of simulation are compared with experimental ones.

In this paper we focused on separation of dominating recombination region that limits total charge carrier lifetime and efficiency in conventional multicrystalline silicon solar cell. According to the Grover's model, we considered SRH-recombination in 3 active regions: interface, depletion region and quasi neutral part of base. We present theoretical calculations and experimental measurements to estimate contribution of every region in total recombination rate. We found that charge carrier lifetime of investigated multicrystalline silicon solar cells is limited by charge carrier recombination in the depletion region.

In this paper we present results of our developments in computer laboratory works for students studying materials of micro- and nanoelectronics. We developed several works to investigate dielectric permittivity and loss tangent, conductivity of metals and alloys, volume and surface resistance of dielectric materials, breakdown of dielectrics, properties of magnetic materials and thermal analysis of metal alloys. These works could be used for simulating physical processes in solid state materials. Virtual laboratory complexes developed in the environment of engineering graphical programming NI LabVIEW.

Measurement complex on the basis of atomic force microscope for investigating electrophysical properties of semiconductor barrier structures is developed and described in this paper. Electromechanical model of point barrier metal-semiconductor contact is clarified. A method to measure electrical capacitance of point barrier contact is described. We developed software to control measuring complex and obtained data about distribution of charge carriers in structures with quantum wells.

In this paper we linked electrophysical properties of multilayer barrier structures based on crystalline and disordered semiconductors with density of electronic states localized in a mobility gap and their energy distribution. We propose experimental method to investigate built-on electric field distribution and its mathematical model. A measuring equipment to realize this method and used test structures is described. The obtained results are analyzed. We marked directions for further researches to improve the method.

In this work a P3HT-based polymer solar cells are investigated by complex combination of experimental electrophysical methods. The existence of the high value deep levels is determined. Influence of these centers on the solar cell performance is shown.

Analysis of existing theoretical concepts in low-frequency noise generation mechanisms in semiconductor barrier structures is performed. It is shown that investigation and simulation of voltage-noise characteristics offer an opportunity to calculate deep level parameters more precisely and to predict semiconductor devices reliability.

The measurement complex based on the cryostat Janis CCS-400/204N that allows making measurements in vacuum in temperature range 7–500 K is described. Thus a high sensitive measurement complex is developed to investigate noise power spectral density in the frequency range 10−3–104 Hz, temperature range 7–500 K and DC voltage range at samples 0–50 V.

In this paper the results of charge carrier bulk lifetime in multicrystalline silicon solar cells obtained by mathematical simulation and experimental investigation by low-frequency noise spectroscopy are presented. These results allow to clarify recombination processes and their influence on carrier lifetime. Also deep levels in a silicon band gap that affect results bulk lifetime and cell performance are investigated by I-DTLS method. Activation energy of these levels is determined.

The radionuclides (88)Zr and (89)Zr have been produced by cyclotron irradiation of (nat)SrO with 35 MeV α-particles at a beam current of 15 μA. The thick source production yield of (89)Zr is ~3.1 MBq μA(-1) h(-1). A two-step radiochemical purification utilising anion-exchange chromatography in hydrochloric and hydrofluoric acids has been developed to separate (88,89)Zr from the target material, natural strontium, the target substrate, aluminium, and long-lived (88)Y.

In this paper we have studied the possibility of determining the chemical elements in coal samples using X-ray fluorescence analysis and have found a relationship between the coal calorific value and its ash content with the coal moisture accounting. The amount of coal ash can be determined by the content of the basic chemical elements, such as Si, Sr, Fe, and Ca. It was concluded that the calorific value of coal can be estimated from the ash content in coal without the calorimetric measurements. These correlation coefficients were calculated for coal from several coal mines in Mongolia. The results are in good agreement with the results of chemical analysis.

We measured for the first time the isomeric ratios in 107Ag(γ, n)106m,gAg reaction by using the activation method and γ-ray spectroscopic method for the whole giant dipole resonance region. The high-purity natural Ag foils in disc shape were irradiated with bremsstrahlungs generated from an electron accelerator Microtron. The induced gamma spectra in the irradiated foils were measured by the high resolution γ-ray spectroscopic system which consists of a high-purity germanium detector and a multichannel analyzer. In order to improve the accuracy of the experimental results, necessary corrections were made in the γ-ray activity measurements and data analysis. The results were analyzed, discussed and compared with those of other authors. For the above mentioned reaction, the isomeric ratios in the energy range from 14 to 24 MeV bremsstrahlungs in this work (except the values at 14, 18 and 20) are new measurements.

We have determined the isomeric ratios in 113In(γ, n)112m,g In and 113In(γ, 2n)111m,g In photonuclear reactions of natural indium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna. The gamma spectra of the samples irradiated were measured with a spectroscopic system consisting of an 8192-channel analyzer and a high-energy resolution (180 keV at gamma ray 1332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors. For both the mentioned reactions, the isomeric ratios in the bremsstrahlung energy range from 19 to 24 MeV in this work are new measurements.

This work discusses the combination of pressure and particle velocity measurements in a single sensing element for underwater seismic applications. In such applications the sensing elements, usually pressure sensors arranged in linear arrays (streamers), receive from the bottom layered structure replicas of a broadband signal generated by a seismic source. In spite of careful setup of sound-receiver geometries, the useful replicas for bottom characterization are contaminated with other replicas, particularly surface reflected ones (ghosts). Since, single pressure sensors are omni-directional it is difficult, if not impossible, to filter out the nuisance replicas at sensor level. However, sensors composed by collocated or closely located pressure and vector field measurements can achieve spatial selectivity. Herein, we analyze the spatial filtering capabilities of various pressure-pressure, particle velocity-particle velocity and pressure-particle velocity combinations in light of seismic applications for narrow band signals. Simulations with the OASES code show that narrow band spatial filtering characteristics of the various combinations can be extended to broadband signals. These results were verified for experimental data acquired by 10 cm apart vector sensors measuring pressure and particle velocity in the 800–1250 Hz band, during the Makai Experiment 2005 sea trial, off Kauai I., Hawaii (USA).

The deep understanding of physical processes and availability of accurate mathematical models are necessary for design and manufacturing of high efficiency solar cells. It allows to predict more precisely the characteristics of solar cells in dependence of photovoltaic properties of materials and constructions. The method of calculating of the collection efficiency of photogenerated charge carriers is proposed in this work. The influence of high density of localized states in mobility gap of a-Si:H on solar cell efficiency is considered.

The article deals with the problem of drift of atomic-force microscope probe in local analysis of the molecular-chemical composition of structures with nanometer resolution. The method of mathematical modeling of image distortion due to drift and its application for a correction of movement trajectory of atomic-force microscope probe are shown.

We have determined the total bremsstrahlung photon fluxes with end-point energies in the giant dipole resonance (GDR) region produced by electron accelerator Microtron MT—25 (the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia) and that of 65 MeV bremsstrahlung produced by the linear electron accelerator (the Pohang Neutron Facility, Pohang, South Korea). The method that we used was the photon activation technique. To ensure the accuracy of the results, we carried out simultaneous photon activation of two monitors made of Cu and Au foils in the same irradiation conditions. The results are discussed in the paper.

We have determined the isomeric ratios in 113In(γ, n)112m,gIn and 113In(γ, 2n)111m,gIn photonuclear reactions of natural indium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at the electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna. The gamma spectra of the samples irradiated were measured with a spectroscopic system consisting of an 8192-channel analyzer and a high-energy resolution (180 keV at gamma ray 1332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors. For both the mentioned reactions, the isomeric ratios in the bremsstrahlung energy range from 19 to 24 MeV in this work are new measurements.

The leaves, stem, and roots of two types of shrubs (tea (Camellia sinensis) and sweet leaf (Sauropus androgynus)) and two types of herbs (vetiver grass (Vetiveria zizanioides L. Nash) and maize (Zea mays L)) and the Thucuc soil where the plants were growing were collected to be studied. The contents of 22 elements in the samples were determined by three methods: X-Ray fluorescence analysis (XRFA), gamma activation analysis (GAA), and the tracking method to study the distribution of these elements in plants and the soil-plant relationship. This study was carried out at the Flerov Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research (JINR), Dubna, Russia. The distribution of the elements in the soil-plant system was studied.

A method to produce (117m)Sn radionuclide using accelerator production route is described. A new method is proposed to separate the (117m)Sn. Specific activities and thick target yield for (116)Cd(α,3n)(117m)Sn reaction at E(α)=35MeV bombarding energy were determined. The estimated production yield of (117m)Sn was 37.5kBq/μAh for 13.16 mg/cm(2) natural cadmium-oxide target and 410 kBq/μAh for 11.07 mg/cm(2) highly enriched (95%) (116)CdO target. The method developed for separation of (117m)Sn from Cd using anion-exchange resin (Dowex -1×8, fluorine form, 400 mesh) can achieve 98% radiochemical yield of (117m)Sn with more than 99% radionuclidic purity. The estimated specific activity is 2.4 GBq/mg that can be reached with the used irradiation conditions.

We have determined the isomeric ratios in 120Te(γ, n)119m,gTe, 122Te(γ, n)121m,gTe, 128Te(γ, n)127m,gTe and 130Te(γ, n)129m,gTe photonuclear reactions of natural tellurium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region. The investigated samples were irradiated at electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The gamma spectra of the samples irradiated were measured with spectroscopic system consisting of 8192 channel analyzer and high-energy resolution (180 keV at gamma ray 1,332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors.

The concentration of natural radionuclides and the feasibility of recovery of uranium from browncoal ash of a Mongolian cogeneration plant were investigated. The concentrations of the elements were determined by instrumental gamma-activation (IGAA) and X-ray fluorescence (XRF) analysis. Uranium from brown-coal ash was leached with an 8 M HNO3 + HF (10%) mixture. The extraction of uranium from the solution and its purification for the removal of accompanying elements were carried out on an anion exchanger. An ash sample after leaching contains neither natural radioactive elements (238U and 232Th) nor their decay products, thereby allowing for the use of the ash as a building material.

The yields of 135Cs nuclei in a high-spin (19/2) isomeric state and of nuclei neighboring it were measured for photonuclear reactions of the (γ, f) and (γ, α) types. The experiments in question were performed by using bremsstrahlung from a microtron at the maximum electron energy of 25 MeV. The product nuclei were identified by their half-lives and by the lines of gamma radiation emitted in their decay, and the reaction yields R were determined by the ratios of the intensities of these lines to the bremsstrahlung flux. The cross sections for isomer production were calculated, and the angular momenta of product nuclei immediately before the cascade of gamma transitions populating the ground or an isomeric nuclear state were evaluated on the basis of these results. An enhanced yield of the high-spin isomer of 135Cs in the fission reaction in relation to the respective (γ, α) reaction and in relation to the results of the calculations is found.

The photonuclear reactions of (γ, xn) or (γ, xnp) types can be used to produce high-intensity neutron sources for research and applied purposes. In this work a Monte-Carlo calculation has been used to evaluate the production yields of neutrons from the (γ, n) and (γ, 2n) reactions following the bremsstrahlung produced by 100 and 200 MeV electron beams on the tungsten target. Our calculations indicated that the neutron yield is an increasing function of the target thickness in a considered range from 1.5 to 2.5 mm.