The synergy problem was discussed linking Se nanoparticles and different soil fertility agents. Se zero-valent-state nanoparticles were investigated as fertilizers and antioxidants. A technology was proposed for producing Se zero-valent-state nanoparticles. Se nanoparticles were obtained by laser ablation of Se in water using a fiber ytterbium laser, with a wavelength between 1060 and 1070 nm, a pulse repetition rate of 20 kHz, a pulse duration of 80 ns, and an average power of 20 W, and a copper vapor laser with wavelengths of 510.6 and 578.2 nm and an average power of 8 W. The main particle mass part shifted from 800 nm to a size less than 100 nm, corresponding to the increase in the laser fragmentation time. The resulting nanoparticles were monodisperse in size and mass. The Se nanoparticle water suspension was introduced into the soil. The soil Se nanoparticle concentrations were about 1, 5, 10, and 25 μg kg –1 . An experiment was carried out in a climate chamber in two series: (1) growing plants in soil imitating the standard organogenesis environment conditions such as illumination of 16 h per day, temperature of 22 °C, soil humidity of 25% SDW, and an experiment duration of 30 days and (2) growing plants in soil under changing environmental conditions of organogenesis. The standard environmental conditions for the first 10 days are illumination of 16 h day –1 , temperature of 22 °C, and soil humidity of 25% SDW. The plant stress for 5 days is hyperthermia of 40 °C. The standard environmental conditions for the next 15 days are illumination of 16 h day –1 , temperature of 22 °C, and soil humidity of 25% SDW. At standard organogenesis, the plant leaf plate surface area was 30 ± 2 cm 2 in the control option, and the Se nanoparticle doses were correspondingly 1 μg kg –1 for 32 ± 3 cm 2 , 5 μg kg –1 for 37 ± 2 cm 2 , 10 μg kg –1 for 38 ± 3 cm 2 , and 25 μg kg –1 for 28 ± 4 cm 2 . Hyperthermia stressed plant growth was studied. The highest plant growth rate was in Se nanoparticle concentrations of 5 and 10 μg kg –1 . The eggplant growth on the soil with the Se nanoparticle addition at a concentration of 10 μg kg –1 of leaf plate surface area was twice compared to the eggplant growth in untreated soil. The same was for tomato plants. The leaf plate surface area of the cucumber plant grown using Se nanoparticles was 50% higher compared to the control option. The Biogeosystem technique methodology of 20–45 cm soil-layer intrasoil milling for soil multilevel aggregate system formation and intrasoil pulse continuous-discrete watering for soil water regime control was proposed for the Se nanoparticles for better function in the real soil, providing a synergy effect of soil mechanical processin...

We report the generation of molecular hydrogen from water by laser irradiation, without any electrodes and photocatalysts. A near infrared pulsed nanosecond laser is used for exposure of colloidal solution of Au nanoparticles suspended in water. Laser exposure of the colloidal solution results in formation of plasma of laser breakdown of liquid and emission of H 2 . The rate of H 2 emission depends critically on the energy of laser pulses. There is a certain threshold in laser fluence in liquid (around 50 J/cm 2 ) below which plasma disappears and H 2 emission stops.H 2 emission from colloidal solution of Au nanoparticles in ethanol is higher than that from similar water colloid. It is found that formation of plasma and emission of H 2 or D 2 can be induced by laser exposure of pure liquids, either H 2 O or D 2 O, respectively. The results are interpreted as water molecules splitting by direct electron impact from breakdown plasma.

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Beryllium nanoparticles are generated upon ablation of a beryllium target in water by a copper vapour laser. The average size of single crystalline nanoparticles is 12 nm. Ablation of a beryllium target in aqueous solutions of uranyl chloride leads to a significant (up to 50 %) decrease in the gamma activity of radionuclides of the uranium-238 and uranium-235 series. Data on the recovery of the gamma activity of these nuclides to new steady-state values after laser irradiation are obtained. The possibility of application of copper vapour lasers for radioactive waste deactivation is discussed.

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