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The present work is a review of methods characterizing radiation resistance of optical materials and fibers designed for pulsed nuclear reactors.

Data on the evaluation of the effect of ten preparations based on humic substances and silver (FlorHumat, Flora-S, Edagum, Fitop Flora-S, Zerebra agro, BatyrMax, Batyr 40N, Batyr 40N + Max, Azofoska) on the productivity of spring soft wheat are presented. Plant productivity was studied according to the following parameters: plant phase (according to the Eucarpia scale), the number of germinal and coleoptile roots, the length of germinal and coleoptile roots, the number and length of nodal roots, the total mass of roots, the mass of the vegetative part of plants, the length of the spike, the number of spikelets in the wheat spike, the number of grains in the wheat spike, the mass of the spike, the height of plants, the area of the flag leaf and preflag leaf, productive tilling capacity, and general tilling capacity. The foliar treatment of plants with the preparations was carried out in appropriate concentrations in the evening during the phases of wheat tillering and flag leaf formation. The biological yield of the wheat was most strongly influenced by the BatyrMax preparation. The Edagum preparation showed maximum efficiency in the number of significant positive changes in wheat productivity compared to the control (untreated plants) and background (the plants were treated with the Azofoska preparation). The similarities in the action of Edagum, Fitop Flora-S and Zerebra agro, and Batyr 40N + Max preparations on the changes in most of the wheat productivity indicators were revealed. There was no statistically significant effect of Flora-S, FlorHumat, and Azofoska on the yield.

The paper presents data on the evaluation of the effect of ten preparations based on humic substances and silver (FlorhGumat, FloraS, Edagum, Fitop Flora-S, Zerebra agro, BatyrMax, Batyr 40N, Batyr 40N + MAX, Azofoska) on the productivity of spring soft wheat. The productivity of wheat was studied in indicators of: the phase of the plant (according to the scale of Eucarpia) the number of germinal, coleoptile roots, the length of the germinal, coleoptile roots, the number of nodal roots, the length of nodal roots, the summary mass of the roots, the mass of the vegetative part of the plants, the length of the wheat spike, the number of spikelets in the wheat spike, the number of grains in the wheat spike, the mass of the spike, the height of the plants, the area of the flag leaf, the area of the pre-flags leaf, productive tilling capacity, general tilling capacity. Out-root treatment of plants with preparations in appropriate concentrations was carried out in the evening hours during the phases of wheat tillering and the formation of a flags leaf. The greatest influence on the productivity of wheat was provided by the preparation BatyrMax. The preparation Edagum showed maximum effectiveness in the number of reliable positive changes in the productivity of wheat compared to the control (untreated plants) and background (the plants were treated with the preparation Azofoska). Similarities in the action of Edagum, Phytop Flora-S and Zerebra Agro, Batyr 40N + Max on the changes in the most of the wheat productivity indicators were revealed. There was no statistically significant effect on the yield of Flora-S, FlorHumat, Azofoska.

Based on studies of the population structure of the beaked redfish Sebastes mentella in the Atlantic and Arctic oceans, a conclusion has been made about the existence of another, epigenetic, trend of its intraspecific differentiation, in addition to the population trend. Analysis of the vast array of our data and those available in literature, which were obtained by the methodological approaches accepted in population biology, made it possible to distinguish three isolated populations of beaked redfish: the North Atlantic, the Norwegian Barents Sea, and the Flemish Cap. The first two are subdivided into demersal and pelagic epigenetic groups that differ morphophysiologically and ecologically. One of the main factors of the epigenetic differentiation of beaked redfish is ontogenetic—individuals reach sexual maturity at different times. Based on the dynamics of the physiological condition of gonads, two groups of fish are identified: early maturing individuals that mainly inhabit the ocean pelagic zone and late-maturing fish that predominantly live in the near-bottom layer along the continental slope. In the first group, the mass maturation of redfish (50% of individuals) occurs at an FL of 29–33 cm and the age of 9–12 years; in the second group, it occurs at an FL of 35–43 cm and the age of 14–19 years. Another factor of epigenetic differentiation is biotopic; it is manifested as the association of discrete groups with different biotopes. Late-maturing redfish stay in the near-bottom layer of the continental and island slopes throughout the year, while early maturing individuals tend to live in the pelagic zone of open ocean areas. The biotopic epigenetic differentiation is closely related to the onset of return migrations from the nursery grounds of juveniles upon their reaching maturity. Juvenile beaked redfish stay in the nursery ground, which is located in the shelf and shallow coastal waters, up to the age 6–10 years. Early maturing individuals are the first to leave the juvenile grounds and move to the ocean pelagic waters. Late-maturing fish, as they grow during prolonged (up to 5–7 years) migration, are recruited to demersal aggregations in deep-sea areas on continental slopes. The complication of the species’ ecological structure due to the differentiation of epigenetic groups by biotopes has led to trophic specialization and weakening of the competitive interactions between them. Their habitation in different biotopes and the physiological polymorphism of redfish have not affected the unity of species populations. In the breeding season, there is no spatiotemporal isolation between the epigenetic groups, and the demersal and pelagic aggregations are replenished by common sources.

Currently, in connection with the onset of environmental and other planetary problems, more and more importance is attached to the transition to sustainable development. Sustainable development in rural areas should be focused on the restoration and preservation of natural ecosystems, including water bodies. The paper discusses a number of phenomena and objects reflecting the ecological state of pilot rural areas that were studied in the framework of the presented Russian-Finnish projects. The project activities helped to improve the ecological state of several agricultural enterprises and to familiarize the population with environmental requirements. Particular attention was paid to working with students of pilot schools for their environmental education. They not only studied nature, but participated in actions to work with garbage, conducted population surveys, prepared a number of projects, including the development of agri tourism and the ecological development of individual villages.

In the research, long-term data characterizing the wheat productivity and degree of its affection by diseases were compared with the natural and climatic factors of the NorthWestern region of the Russian Federation. The comparative analysis of the protein growth stimulant (PGS) and organomineral fertilizers’ influence on productivity, yield structure, and disease resistance of the VIR soft wheat was carried out. The greatest influence on the potential (estimated) wheat yield growth was exerted by the preparations “Zerebra agro” and “Edagum”. Foliar spraying with the protein growth stimulant resulted in an increase in wheat yield by 31.5% compared to the control. After applying the protein stimulant, a decrease in the degree of wheat powdery mildew development by 15.7% was revealed compared with the control. Organo-mineral fertilizers had insignificant effects on the disease development. The “Zerebra agro” preparation had high biological effectiveness against wheat leaf diseases (brown rust, powdery mildew).

The data on the size composition, the organ system indices, and the spatial distribution of the rex sole Glyptocephalus zachirus in the northwestern part of the Bering Sea for June–August 2000 has been reported.

On the basis of the results of complex interdisciplinary investigations of the population composition and structure of the beaked redfish Sebastes mentella of the Atlantic and Arctic oceans, its three populations are discerned relatively isolated from each other by the system of permanent marine currents—North Atlantic, Flemish-Cape, and Norway-Barents Sea. The population structure of the species in the southern part of its area corresponds to the model of a local stock. Interaction of the North Atlantic and the Norway-Barents Sea populations well correspond to the model of fluctuating stocks. Redfish aggregations in different biotopes (mesobenthal and mesopelagial) are intrapopulational epigenetic groups. In the period of warm and anomalously warm years, a part of mature specimens from the pelagial of the North Irminger Sea make an irreversible migration to the southern part of the Norwegian Sea and form there mixed aggregations of fish from the North Atlantic and Norway-Barents Sea populations. With consideration of the effect of climatic–oceanological processes, a principally new scheme is elaborated describing the process of seasonal migrations of redfish in the mesobenthal and mesopelagial. The previous views on direction of return migrations of redfish of the Norway-Barents Sea population are reconsidered. Juveniles from the western part of the Barents Sea and Spitsbergen not only supplement the demersal aggregations but also migrate to the pelagial of the Norwegian Sea.

The results of experimental studies of the dependence of potato yields on the application of the BIOGUM compost, biological plant protection products and technological methods of tillage and plant care are presented. The experimental and analytical methods were used. The whole range of agricultural practices has a significant impact on the potato yield. The deep loosening between rows is promising and can increase the yield by 57%. The use of Vitaplan, SP has a significant effect on the potato yield. It increased the yield from 17.8 t/ha to 25.3 t/ha, i.e. by 7.5 t/ha or 42%. The use of biofungicide along with the compost made it possible to produce the yield of 29.2 t/ha, and increase it by 64%. The dependencies can be used for developing biologized technologies of potato cultivation in specific economic conditions.

Results of studies of the structure and specific features of formation of aggregations of deepwater redfish Sebastes mentella in the Norwegian Sea pelagial are provided. Data on the biological characteristics of S. mentella from different regions of the Norwegian Sea pelagial do not allow us to consider its aggregations as separate populations. On the basis of comparative analysis of the structure of aggregations in the Norwegian Sea and of population parameters and specific features of the life cycle of S. mentella in different parts of the Atlantic Ocean, its complex intraspecies organization at sites of overlapping of two largest populations—North Atlantic and Norwegian-Barents Sea-was established. The formation of pelagic aggregations in the water area of the Norwegian Sea occurs due to migration of maturing and mature individuals from the adjoining water areas. In the southern areas of the Norwegian Sea, dominant recruitment comes from the pelagial of the northeastern part of the Irminger Sea, which is promoted by the direction of streams of the North-Atlantic Current; it is not excluded either that fish can migrate to the southern part of the sea from the slopes of the Faeroes, Faeroes-Icelandic threshold, and the western coast of Norway. Migration to the northern areas of the sea is mainly performed by rapidly maturing fish from the rearing region from the western slopes of the Barents Sea and Spitsbergen Archipelago. The presence of seasonal migrations hinders the formation in the pelagial of perch isolated groups and promotes their migration.

Data on the spatial-bathymetric distribution, size and age composition, sex ratio, and feeding of deepwater redfish Sebastes mentella in the pelagial of the northern Atlantic (Irminger and Labrador seas) during mating are provided. From 1982 to 1999, the mating of S. mentella took place in the central and southern parts of the Irminger Sea (56°–62° N, 30°–43° W); since 2000 it took place in two geographically isolated areas: in the water area of the open part of the Labrador Sea, at sites of the south of the Irminger Sea adjacent to it (54°–58° N, 38°–50° W), and above the western slopes of the Reykjanes Ridge (62°–65° N, 25°–34° W). It is assumed that during mating in the northern area mixed aggregations of two ecological groups of S. mentella—an oceanic group that distributes in the pelagial and a bottom group that inhabits the slopes of Iceland—are formed. The formation of isolated areas of mating of the species is determined by the orientation of feeding migrations that are simultaneously migrations to spawning grounds. Fish of medium sizes migrate to spawning grounds in the southwestern direction, while large fish migrate in the northern direction; the fertilization of females in these areas occurs at the end of summer. In S. mentella, the seasonal and age differences in food composition are clearly pronounced. With the onset of mating, the males’ intensity of feeding in both regions decreases by a factor of 1.5–2.0, while females continue to feed actively.

The analysis is conducted of the biological and genetic characteristics of deepwater redfish Sebastes mentella from the open part of the Norwegian Sea. A similarity of the studied sample with analogous groups of deepwater redfish from the Northeast Atlantic in biological parameters and their dynamics is revealed. Polymorphism is registered in three of the nine studied enzyme loci: malic enzyme (NADF-dependent malatedehydrogenase), MEP-1*; phosphoglucomutase from the liver, PGM-2*; and glucose-6-phosphateisomerase, PGI*. A pairwise comparison of allele frequencies shows a similarity of the samples of deepwater redfish from the enclave of the Norwegian Sea. In addition, based on a pairwise analysis, significant differences are absent between the samples with similar biological characteristics from the open part of the Norwegian Sea and the Irminger Sea.

The spatial distribution of redfish Sebastes mentella in the pelagic zone of the northern part of the Atlantic Ocean (the Irminger Sea and the Labrador Sea) is investigated. Analysis of the data on size-age composition, sex ratio, ratio of mature and immature specimens, rate of maturation, composition of the parasite fauna, infestation level, infestation with the copepod Sphyrion lumpi, and occurrence of pigment formations on the body of redfish from the investigated areas indicate the absence of stable isolated aggregations of this species in the oceanic pelagial of the North Atlantic. Pelagic aggregations are formed of rapidly maturating specimens migrated from the slopes of Greenland. The spatial variation of the size-age composition of redfish depends on the life cycle and regional hydrological conditions.

Results of comparative analysis of several ecological and biological indices of Sebastes mentella from the northern Atlantic (the Irminger Sea, Reykjanes Ridge) inhabiting different depths, 0–500 and 501–1000 m, are provided. A considerable similarity in the rates of linear and weight growth, sexual maturation, composition of parasitofauna, the degree of invasion by parasites of most species, specific features of invasion by copepod Sphyrion lumpi, as well as the pattern of pigment formations on the skin of S. mentella from two studied layers, testify to the absence of isolated groups of this species in the pelagial of the Irminger Sea. It was established that the formation of perch aggregations at a depth larger than 500 m takes place due to a partial redistribution from the upper layer of individuals aged 5 to 18 years and a complete departure to large depths of perch individuals older than 18 years. A conclusion was made that it is incorrect to use as a criterion for the intraspecies differentiation of the perch the insignificant differences in the occurrence of pigment formations on the skin that are the result of age changes in fish and an obvious pathology of this phenomenon. A decrease in the occurrence of melanin inclusions in the muscular tissue of fish at a depth larger than 500 m is also related to age changes and the change in the diet of the perch. Vertical variation, in particular biological parameters in pelagic aggregations, was determined by specific features of biology, ecology, and the life cycle of the species. In establishing measures of control of the international fishery in the pelagial of the Irminger Sea, it is necessary to proceed from the unity of aggregations of S. mentella throughout the vertical of their distribution.

In previous chapters, we have reviewed pumping methods for gas-medium and condensed-medium lasers using nuclear reactors as neutron sources. We also reviewed the characteristics of these lasers and the potential to use them in different nuclear-laser devices. The highest specific power depositions for gas media (q ≤ 5 kW/cm3) can be obtained if a laser cell that has a uranium layer or is filled with 3Не is placed inside the core of a pulsed reactor at the minimal possible pulse length for pulsed reactors, ~100 μs. However, these specific power depositions are sometimes not sufficient to reach the lasing threshold of certain active media.

At present, direct nuclear pumping is implemented for gas laser media in which the populating of lasing levels occurs as a result of processes occurring in a high-pressure low-temperature plasma formed by ionizing radiation. Sometimes this plasma is called nuclear-excited plasma.

In Chap. 2 we examined rather simple NPL designs for searching for and studying characteristics of laser active media, but there are also more complex nuclear laser devices. As a rule, they are structural elements of multichannel reactor lasers operating in stationary or pulsed modes, and are intended to study the specifics of their operation. This chapter examines some of these devices, whether in operation or still being designed.

Chapter 6 gives a brief overview of designs for nuclear laser setups with a pulse duration of ~10 ms (OKUYAN and LIRA setups). Their operation is based on the “initiating reactor–subcritical laser block” scheme. The literature has repeatedly suggested different design schemes for stationary nuclear laser facilities or reactor-laser (RL) based on gas laser media. The term RL was apparently first proposed in article [1], where the potential of removing energy in the form of laser radiation from the reactor core during the relaxation stage was noted in principle. The most interesting version of the RL is a device where, as a consequence of spatial overlapping of the nuclear fuel and laser medium, a significant portion of the nuclear energy is converted into laser radiation bypassing the intermediate thermal energy stage.

The most progress in searching for active media for NPLs, studying their characteristics, and developing various nuclear-laser devices was achieved when high-pressure gas media were used. However, there have been repeated attempts in Russia and the United States to pump different condensed media with nuclear radiation and carry out feasibility studies on developing powerful nuclear-laser devices based on these media.

Investigations of optical inhomogeneities in sealed NPLs have revealed that flowing of the gas medium through the laser cavity is a necessary condition for achieving CW lasing in the stationary and quasi-stationary excitation modes. Gas heating is a no less important factor that requires the implementation of gas flowing.

This book primarily discusses NPL research in Russia. The Russian program has been larger and remains active whereas work in the United States and elsewhere has dwindled. Shortly after the end of the Cold War, two circumstances combined to cause stoppage of NPL work. While the military need ceased, public opposition to nuclear power mounted following the Three Mile Island Nuclear reactor accident in the United States. Such concerns clearly carried over to a reactor pumped laser, i.e. to NPLs. Here we briefly review earlier work is the United States, prior to a build-up of effort as part of the “Star Wars” program as cold war tension grew.

As was noted in Sect. 1.2 of Chap. 1, the nuclear reactions that can be used for pumping gas NPLs in experiments with pulsed reactors are: $$ {}^3\mathrm{H}\mathrm{e}+n\to {}^3\mathrm{H}+p+0.76\;\mathrm{M}\mathrm{e}\mathrm{V} $$ $$ {}^{10}\mathrm{B}+n\to {}^7\mathrm{L}\mathrm{i}+\alpha +2.38\;\mathrm{M}\mathrm{e}\mathrm{V}, $$ $$ {}^{235}\mathrm{U}+n\to \mathrm{fragments}+168\;\mathrm{M}\mathrm{e}\mathrm{V}. $$ When reaction (7.1) is used, the laser medium is excited by protons and tritium ions. In this case, 3He plays the role of a buffer component of the laser mixture and is simultaneously a volume pumping source. Calculations of the specific energy deposition to the gas medium when the reaction (7.1) is used were carried out in the studies [1, 2]. The gas pressure and the transverse dimension of the laser cell were varied (it was assumed that the length of the cell greatly exceeded its transverse dimension). It was shown that for each pressure value there is an optimal transverse dimension of the cell. When the dimensions are less than optimal, the losses of reaction (7.1) products on the walls of the cell become great. When the dimensions are greater than optimal, the decrease of the neutron flux in the direction from the cell boundary to the depth of the gas volume starts to have an effect. Some results of calculations are provided in Figs. 7.1 and 7.2. It should be noted that the model [2] makes it possible to perform calculations for different neutron spectra when more precise deceleration principles of charged particles are used. The results of the calculations in studies [1, 2] for the case of a mono-energetic flux of thermal neutrons differ by 10–15 % (Fig. 7.1).

The short range of fission fragments causes a specific energy input inhomogeneities which, along with excited gas heat exchange with laser cell walls, leads to density spatial redistribution, i.e., to the violation of active medium optical homogeneity. As noted in paper [1], with a reference to the 1980 report of A. N. Sizov and Yu. N. Deryugin, numerical and theoretical investigations of the dynamics of optical inhomogeneity origination and development in nuclear pumping lasers first began at the VNIIEF. During phase one, these investigations only pertained to the phenomena occurring in sealed lasers excited by pulsed neutron fluxes. This important aspect of NPLs is discussed in this chapter.

Presently, known gas NPLs radiate in a wide band of the optical spectrum of 390–5,600 nm using approximately 50 transitions of atoms Xe, Kr, Ar, Ne, C, N, Cl, O, Hg, Cd, and I; the ions Cd+, Zn+, and Hg+; the molecule CO; and the molecular ion N 2 + .

Virtually all of the experimental investigations to seek and study the characteristics of NPLs excited by the products of nuclear reactions were carried out on pulsed nuclear reactors. Pulsed nuclear reactors are distinguished for the composition and structure of their core, the duration and fluence of the neutron pulse, the volume and configuration of the space for the irradiation, and the pulse repetition frequency. Some aspects of the use of pulsed reactors for laser pumping were examined in the survey [1]. This section uses some of the data from study [1], supplemented by information from other sources.

This chapter examines the kinetics of plasmochemical processes and the lasing mechanisms of various types of gas NPLs pumped using neutrons from pulsed nuclear reactors. The lasers considered here typically have Continuous Wave, i.e. CW operation (or, more accurately, quasi-CW) lasing mechanisms, because the characteristic times of basic plasma processes are much less than the durations of pulsed reactor pumping pulses (≥50 μs). To determine the lasing mechanism, it is necessary to ascertain the processes of populating and quenching both of the upper and of the lower lasing levels. Information about the specific features and the constants of the most important plasmochemical processes is contained in a number of studies (see [1–4], for example).

For studying the lasing mechanism of nuclear-pumped IR lasers at krypton and argon atomic transitions, the kinetics of the plasma process is considered and computations are made for the energy and threshold characteristics of He-Kr (λ=2.52 μm) and He-Ar (λ=1.79 μm) lasers excited by uranium fission fragments. The calculated optimal pressures, mixture compositions, laser output powers and threshold characteristics agree satisfactorily with the experimental ones.

This article describes the design of a laser setup excited by 3He(n, p)3H reaction products and intended for investigations of the laser characteristics of 3He mixtures with metal vapors or other gases at temperatures up to 800˚C. This setup could also be used to study the effect of the medium heating on the characteristics of nuclear-pumped gas lasers.

We suggest several cascade lasing schemes: (1) cascade of laser transitions between atom (ion) excited levels when the lower laser level of one laser transition is simultaneously the upper laser level of another transition located below; (2) successive lasing, first, on ion transitions, then after ion recombination on atom transitions; (3) while using multicomponent mixtures, successive lasing on atoms (ions) of separate components. These possibilities are discussed in terms of specific lasers, some of which have been studied experimentally.

The investigation results of the spectral-luminescent characteristics of rare gases He, Ne, Ar, Kr, and Xe and their binary mixtures He-Ne(Ar,Kr,Xe), Ne-Ar(Kr,Xe), Ar-Kr(Xe), and Kr-Xe under high pressures in the 740-1100 nm spectral range are presented. Excitation of gas media was carried out by uranium fission fragments. The information on the absolute intensities of the spectral lines belonging to the transitions of Nel, An, KrI, and XeI was obtained. The lines belonging to atomic transitions of 0, N, and C were also observed.

Data on energy and threshold characteristics of xenon laser in the He-Xe (2.65 μm), Ar-Xe (1.73 μm), and He-Ar-Xe (2.03 and 2.65 μm) mixtures have been measured as a function of xenon partial pressure and output mirror reflectivity. Investigations were carried out using LUNA-2M setup irradiated by neutron flux of VIR-2M pulse reactor with pulse duration of about 3 ms. Using the experimental data and Rigrod model, small-signal gains and saturations intensities were determined.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The review of experimental and theoretical investigations carried out in VNIIF during about 25 years and devoted to the problems of nuclear-pumped lasers is presented.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Quasi-cw laser action with pulse duration up to 10 ms on the 1.59-, 2.45-micrometers atomic Cl transitions and 2.65-, 2.76-micrometers atomic O transitions was observed under uranium fission fragment pumping of atmospheric-pressure gas media. The mixtures of He, Ne, Ar with CCl 4 , CHCl 3 , CF 2 Cl 2 , C 2 F 3 Cl 3 , O 2 , NO, or CO were used. Nuclear pumping of high-pressure gas media at the 2.45- and 2.65-micrometers lines has been achieved for the first time. To our knowledge, the 2.76-micrometers line is a new laser line. The maximum energy parameters (output power of 130 W, power efficiency of about 0.2%) were measured for the 1.59-micrometers chlorine line in He/Ne/CCl 4 (25000/25000/1) mixture at 2 atm pressure. The minimum laser threshold was observed for this line at the thermal neutron flux of 2 X 10 13 n/cm 2 s.