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The principle of operation and technical parameters of excilamps with a small-diameter output window from a series of portable narrow-band ultraviolet and vacuum ultraviolet radiation sources are described. An example of using a KrCl excilamp to excite photoluminescence of crystalline materials is given.

the article presents data on the structure and features of the functioning of the department of agrometeorological forecasts of the Hydrometeorological Center of Russia for timely provision of agricultural industries with correct meteorological information.

the article presents data on changes in the timing of the phases of vegetation of such crops as sunflower and sugar beet

The use of forecasting the productivity of agrophytocenoses with the participation of perennial grasses based on the consideration of moisture conditions in the initial vegetation period is an important element of management in agro-industrial production.

The optical absorption and cathodoluminescence spectra of nine diamond specimens are investigated at the temperatures 295 K and 82–295 K, respectively. By the presence of an N3a electron-vibrational system with a phonon-free line at 2.68 eV, six of them are identified as natural diamonds. By the presence of the electron-vibrational system at 2.56 eV and a structureless band at 2.54 eV, associated with nickel in the optical absorption and luminescence spectra, two specimens are identified as synthetic diamonds grown at high pressures and temperatures. By the presence of exciton luminescence at 5.271 eV and the absence of any spectral, impurity-related peculiarities, one of the specimens is identified as a synthetic diamond grown by the chemical vapor deposition. Based on the data obtained, a procedure is proposed for identifying natural and synthetic diamonds and determining a model scheme of the radiation-thermal treatment of the specimens.

The modern level of research on the inactivation of viruses, bacteria, and living cells under the influence of ultraviolet radiation from excilamps is presented. Special attention is paid to the inactivation of viruses, which is relevant in connection with the spread of coronavirus infections. It has been shown that UVC excilamps, emitting in the wavelength range of 200-240 nm, are an alternative to classical sources of ultraviolet radiation for inactivating viruses. They can be used alone or in combination with known sources (e.g., LEDs, low pressure mercury lamps). A forecast was made for the development of a new technology for disinfecting air and surfaces from infectious agents of various etiologies. (C) 2021 Optica Publishing Group

Results of investigations of UV and VUV radiation sources (excilamps) based on inert gases and mixtures of inert gases with halides are presented. Conditions are described in which maximum radiation parameters are attained. Photoreactors and irradiators promising for application in medicine, agriculture, and gas industry have been developed based on the excilamps.

Numerical simulation of thermal and gas-dynamic processes in barrier-discharge coaxial excilamps is performed, and the conditions of its application are justified. The calculation results are compared with the results of experiments in which the dynamics of heating of a barrier-discharge KrCl-excilamp is investigated for the mixtures of Kr: Cl2 = (400–50): 1 at a total pressure of 100 to 300 Torr. The comparison showed that the selected method and the assumptions made in the calculation model could be applied in practice. Practically important predictions are made about the operating modes of excilamps to ensure their long service life.

The results of investigations of planar and coaxial barrier-discharge KrCl excilamps (λ ∼ 222 nm) are reviewed. Brief information on the developed structures of radiators and power-supply units and the results of life tests are presented. The kinetics of the processes in the working gaseous medium, the possible methods for improving the energy parameters of KrCl excilamps, and prospects of their applications are reported.

Barrier discharges in Xe-I 2 (100-0.04 Torr) mixtures are studied experimentally and theoretically. It is shown that the experimental efficiency and the intensity of radiation in the B → X band of XeI* (253 nm) may reach 5.5% and 9 mW/cm 2 , respectively. The simulation results show that the main energy loss channel is heating of ions. The radiation yield can be increased by shortening the applied voltage pulse duration.

The possibility of improving the parameters of AuGe/Ni- and Ge/Cu-based ohmic contacts to n-i-GaAs by modifying the preliminarily oxidized GaAs surface in a sulfide-containing solution, as well as via the effect of ultraviolet radiation generated with a KrCl excimer lamp on a chalcogenated surface, is studied. It is shown that preliminary oxidation of the n-i-GaAs surface with subsequent chalcogenation makes it possible to decrease the density of the surface states, to increase the reproducibility of the passivation of the surface, and to decrease the reduced contact resistance of the AuGe/Ni ohmic contacts by a factor of 1.5. The treatment of the chalcogenated surface of n-i-GaAs with an ultraviolet radiation with wavelength λ = 222 nm and emission power density W = 12 mW cm−2 performed in vacuum before the deposition of metal layers of the Ge/Cu ohmic contacts makes it possible to decrease the reduced contact resistance by 25–50% andimprove the morphological characteristics of the surface of the contact area.

The radiative and thermodynamic parameters of a dielectric barrier discharge XeBr and KrBr excilamp were studied. The power expended in heating the gas mixture and the excilamp bulb was determined by measuring the fast and slow components of a pressure jump. The power consumed by the exilamp was estimated using oscillograms of voltage and current pulses. The maximum UV power and efficiency of a XeBr excilamp were 3.8 W and 7.5%, respectively. For the same conditions the maximum UV power and efficiency of a KrBr excilamp were 1.6 W and 3%, respectively. Analysis of the experimental results shows that at low mixture pressures most of the discharge power is expended in heating the gas and at the elevated pressure the most of the discharge power goes into the generation of acoustic waves and heating of the excilamp bulb walls through electron and ion bombardment. The concept proposed earlier for the energy balance in DBD lamps as thermodynamic systems was verified.

Photoluminescence and optical transmission spectra of several samples of natural and synthetic diamond and its imitators – fianite and corundum – are investigated. The band-A of luminescence at 440 nm, the vibronic N3 system of luminescence and absorption at 415.2 nm, the fundamental absorption edge at 225 nm, and the secondary absorption below 308 nm are the main identifying markers of natural diamonds. For synthetic diamonds, however, such identifying markers are the free-exciton luminescence at 235 nm, the band-A, and the fundamental absorption edge. Fianites can be identified by the structureless wideband at 500 nm and the wide transmission band in the entire visible range. Colored corundum samples with chrome impurities emit the narrow line at 693 nm and show the absorption band in the 500–600 nm spectral range. A new method for diamond express identification is developed on the basis of measurement of photoluminescence and optical transmission spectra of the samples. It is shown that a diamond tester can be designed combining a spectrometer and a KrCl-excilamp radiating at 222 nm.

Spectral and energy characteristics of nitrogen molecule radiation in dielectric barrier discharges in Ar-N2, Ar-N2-Cl2, and Ar-N2-Br2 mixtures were investigated experimentally. Small additives of molecular chlorine or bromine to an Ar-N2 mixture are found to increase the radiation intensity of the second positive system of nitrogen. The conditions at which the radiation spectrum predominantly consists of vibronic bands of this system are determined. Using a numerical model of plasmachemical processes, it is shown that, at electron temperatures typical of gas discharges (2–4 eV), a minor additive of molecular chlorine to an Ar-N2 mixture leads to an increase in the concentrations of electrons, positive ions, and metastable argon atoms. In turn, collisional energy transfer from metastable argon atoms to nitrogen molecules results in the excitation of the N2(C3Πu) state.

Data for the pressure jump are used to study thermodynamic processes in barrier-discharge excilamps under the conditions of a diffuse (uniform) discharge and microdischarges. It is shown that a linear relationship between the pressure jump and excilamp radiation intensity can help to control the radiation power.

The spectral, energy, and temporal characteristics of E-type discharge plasma radiation in ammonia water are investigated. Barrier and capacitive discharge lamps at A2Σ+ → X2Π transitions of ·OH* hydroxyl and C3Πu → B3Πg transitions are created. The radiant power is about ∼35 and ∼50 mW and the efficiency is ∼0.15 and 0.25% for the barrier and capacitive discharges, respectively.

The spectral and power characteristics of radiation of the second positive system of nitrogen (C3Πu → B3Πg) in Ar-N2 and Ar-N2-Cl2 mixtures excited by barrier discharge have been studied experimentally. Addition of argon to N2 increased the radiation power by sixfold. In the triple mixture Ar-N2-Cl2 = 210/0.5/0.005, minor chlorine additions increased the intensity of the C3Πu → B3Πg transition by 26% compared to Ar-N2 mixtures. Radiation power density of 2.7 mW/cm2 has been achieved. In both binary and triple mixtures, the second positive system of nitrogen was the major contributor to radiation, while the contributions of the fourth positive system of N2* (D3Σu+ → B3Πg), the Vegard-Kaplan transition of N2* (A3Σu+ → X1Σg+), and the D′ → A′ band of Cl2* were negligibly small.

Air-cooled barrier-discharge excilamps with flat exit windows are described. The results of investigations into radiation of lamps on KrCl* (λ ∼ 222 nm), Cl2(λ ∼ 258 nm), and KrBr (λ ∼ 207 nm) molecules are given. The obtained average radiation powers in the UV spectrum region behind a flat window are 10.2, 1.55, and 4.15 W, respectively. The excilamps are intended to uniformly irradiate various objects with areas of up to 200 cm2 in air and various gaseous media. They are also equipped with a system preventing the ozone generated in the lamp from leaving.

The spectral and energy characteristics of multiband barrier-discharge coaxial KrBr excilamps are studied experimentally at pressures from a few tens of Torr to 0.4 atm. It is shown that an increase in the Br2 concentration reduces the emission intensity of KrBr* molecules with respect to the emission intensity of Br2* molecules and reduces the total emission power of the excilamp. This can be explained by the nonradiative decay of exciplex KrBr* molecules caused by their quenching by molecular bromine. The emission power and efficiency in the Kr:Br2 = 400:1 mixture at a pressure of ≈230 Torr and a discharge gap of 8.5 mm were 4.8 W and 2.4%, respectively.

The energy and spectral characteristics of a barrier discharge in a mixture of iodine vapor with krypton have been investigated theoretically and experimentally. The emission spectrum consists of the single I*2 molecular band D′ → A′ peaking at 342 nm, the iodine resonance line at 206.2 nm, and the group of bands corresponding to iodine emission. The highest intensity of the I*2 (342 nm) band was obtained at a mixture pressure near 450 Torr. A mean output power and an efficiency of 550 mW and 1.6%, respectively, have been achieved. It is shown that, for the I2 barrier-discharge excilamp, the homogeneous, rather than filamentary form of discharge glow is optimal from the viewpoint of the highest mean output power. The maximal calculated value of the emission efficiency for the 342-nm band was 5%. The main processes determining energy losses in plasma have been found, and ways to increase the efficiency of emission in the D′ → A′ band of the I*2 molecule have been proposed.

Barrier-discharge excilamps operating in homonuclear chlorine, bromine, and iodine and their mixtures with inert gases have been studied. The spectral and energy characteristics of the barrier-discharge plasma have been obtained. The conditions have been determined at which the band D′ → A′ predominates in the spectra of molecules I*2 (342 nm), Cl*2 (257.8 nm), and Br*2 (291 nm). The efficiencies of I2, Cl2, and Br2 excilamps were found to be 1.6, 2, and 3.8%.

Spectral and energy characteristics of a barrier-discharge excilamp on a mixture of krypton with bromine and chlorine molecules that emits in the range 200–300 nm are presented. The radiation spectrum contains the bands of the B → X transitions of the KrCl* (222 nm) and KrBr* (207 nm) molecules and the band of the D′ → A′ transition of the Br*2 molecule (291 nm). It is demonstrated that the bromine content must be higher than the chlorine content in the triple (Kr−Cl2−Br2) mixtures that are optimal with respect to the radiant power. A radiant power of 0.7 W and an efficiency of 3% are realized. A multiband barrier-discharge excilamp based on the triple mixture exhibits a potentially long lifetime.

The energy and spectral emission characteristics of a barrier discharge are studied in mixtures of inert gases with iodine vapour. The emission spectrum exhibits a strong 342-nm D' → A' molecular band of the I2* molecule, the 206.2-nm resonance line of iodine, and a group of emission bands of iodine. Small admixtures of Ne (5%) to the Ar – I2 mixture increase the emission efficiency and power by a factor of 2–2.5. A sealed off I2 excilamp with the emission maximum at 342 nm is fabricated.

The inactivation of eggs of Opisthorchis felineus and Diphyllobothrium latum in the water under the action of UV excilamps at 222 and 282 nm in dependence on the surface dose of radiation was studied. It was observed that the water disinfection from eggs of helminthes was more efficient at 222 nm, than at 282 nm. At the surface dose up to 5 mJ/cm 2 of UV radiation at 222 nm up to 85 % of Opisthorchis felineus eggs were inactivated. At the comparable surface dose of UV radiation at 222 nm up to 56 % of Diphyllobothrium latum eggs were inactivated.

The subject of investigation is the coaxial two-barrier short-pulse excimer lamp based on XeBr* molecules (λ = 282 nm). When the working mixture (Xe: Br2 = 70: 1) is excited by a high-voltage pulsed nanosecond discharge at a pressure of 1 atm, the peak power of the generated radiation is on the order of 100 kW at an FWHM of 4.5 ns. If the gap between the barriers is small, a train of pulses with an FWHM of 20 ns and a repetition rate of 200 kHz may be obtained.

We have developed a module based on exciplex barrier-discharge lamps for irradiation by high-power narrow-band ultraviolet radiation. The module uses air cooling and is intended for irradiation of substrates such as those used in microelectronics. The module provides close to uniform irradiation on a flat surface with power density up to 35 and 25 mW/cm2 as a result of emission in B–X bands of the molecules XeBr* (282 nm) and XeCl* (308 nm) respectively.

Measuring maximal sniff pressures is an easy way of assessing inspiratory muscle strength. During a static manoeuvre, the pattern of inspiratory muscle recruitment during a sniff can vary from one individual to another. We therefore assessed how voluntarily changing muscle recruitment would affect sniff oesophageal, gastric and transdiaphragmatic pressures (Pes,sn, Pga,sn and Pdi,sn, respectively). Ten normal subjects (age 27-38 years) performed natural sniff manoeuvres ("nat"), and preferentially diaphragmatic ("dia") or extradiaphragmatic ("extradia") sniff manoeuvres, after having learnt to dissociate between the inspiratory muscle groups. Abdominal displacements were monitored using a belt-mounted strain gauge. Natural patterns of muscle recruitment varied among subjects. On average, Pes,sn,nat was [median (range)] 81 (21-105) cmH2O. All of the subjects were able to modify inspiratory muscle recruitment voluntarily. Pes,sn was not significantly affected by the type of manoeuvre performed, as opposed to Pdi,sn, which, as expected, increased with both the diaphragmatic and extradiaphragmatic manoeuvres [Pdi,sn,dia 132 (99-157) cmH2O, Pdi,sn,extradia 96 (50-146) cmH2O, P0.05]. Whatever the manoeuvre, there was no correlation between Pes and Pdi, but Pga and Pdi were correlated during both the diaphragmatic (r = 0.82, P0.05) and the extradiaphragmatic manoeuvre (r = 0.70, P0.05). Pes,sn may have limitations as an index of diaphragm function, but by showing its independence from inspiratory muscle recruitment, this study contributes to its validation as a robust index of global inspiratory muscle strength that is particularly well suited for follow-up studies. This should extend to Pes,sn substitutes measured at the airway opening.

In the present paper, the review of the basic results obtained at the Laboratory of Optical Radiation at High Current Electronics Institute SB RAS during 2007–2009 years is presented. Efficient radiation of Ar2, Kr2, Xe2, KrBr*, KrCl*, XeI*, XeBr*, XeCl*, Cl2* molecules and I atoms was obtained in rare gas or in rare gas–Br2 (Cl2, I2) mixtures. Study of radiation parameters and lifetime period of the manufactured barrier discharge excilamps has been performed.

We have created and tested a coaxial excimer lamp (excilamp) with three barriers and two separate compartments representing serially connected gaps. The emission spectrum of the excilamp exhibits two narrow bands of comparable intensity peaking at 222 and 282 nm, representing the emission due to KrCl* and XeBr* molecules, respectively, at an average output radiant power of 1.2 W.

The energy and spectral parameters of emission of a barrier discharge in chlorine and its mixtures with inert gases are studied experimentally. The barrier discharge in chlorine was homogeneous at pressures up to ≈9 Torr and its spectrum contained the 3Π2g→3Π2u, 3Π2g→3Σ2u+ and 1Σu+→1Σg+ bands of Cl2* molecules. After the addition of an inert gas, the 257.8-nm 3Π2g→3Π2u band made the main contribution to the spectrum. The maximum efficiency and power of the Cl2 excilamp were obtained for the chlorine—argon mixture and amounted to 0.7% and 1.3 W, respectively.

The energy and spectral parameters of a barrier discharge in a mixture of argon with hydroxyl ?OH are studied experimentally. A sealed lamp with the radiation intensity maximum at ? = 309.2 nm, an emitting surface area of ~700 cm2, and a radiant excitance of 1.5 mW cm-2 has been fabricated. The radiant power of the lamp is 1.1 W.

Study of radiation parameters and lifetime period of the manufactured barrier discharge excilamps has been performed. Average power of radiation for the just sealed off KrCl (λ ∼ 222 nm) excilamp exceeded 100 W was obtained. The emitter with length of 1200 mm at external diameter 65 mm was tested. Length of a radiating surface has made 1100 mm. The tests were carried out with air cooling system. Maximal radiation power density was of 50 mW/cm2, that corresponds to excilamp radiant power more than 100 W. UV output power of ∼75 W and efficiency up to 10 %, respectively, at λ ∼ 308 nm (XeCl* excilamp) were obtained under excitation by pulses with frequency of 100 kHz. Application of water cooling allows increasing the radiant emittance of DBD coaxial excilamps. It was noted that in the coaxial quartz tube KrCl - excilamps excited by a barrier discharge, the maximum emission efficiencies are observed for a discharge in the form of diffuse cones. VUV output power of ∼120 W at λ ∼ 172 nm was obtained under excitation by pulses with frequency of ∼100 kHz.

In the present paper, the review of the basic results obtained at the Laboratory of Optical Radiation at High Current Electronics Institute SB RAS during 2007-2008 years is presented. Efficient radiation of Ar 2 , Kr 2 , Xe 2 , KrBr*, KrCl*, XeI*, XeBr*, XeCl*, Cl 2 * molecules and I atoms was obtained in rare gas or in rare gas - Br 2 (Cl 2 , I 2 ) mixtures.

Transmission and luminescence spectra of natural or/and synthetic samples of corundum, diamonds and phianites are obtained by irradiation of a KrCl-excilamp (222 nm) driven by the barrier discharge. It is offered to use a KrCl-excilamp for development of devices for nondestructive identification of diamonds and their imitations.

Pre-production models of excilamps developed in the laboratory of optical radiation are described; main characteristics of radiators and their power supplies, portable UV-excilamps of the barrier or capacitive discharges, and also powerful VUV-excilamps of the barrier discharge which can be used for cleaning or modifying material surfaces are presented.

The study of features of XeBr-excilamp (282 nm) and low-pressure Hg-lamp (253.7 nm) radiation impact on Escherichia coli bacterial culture are presented. It is shown for the first time that both sources of radiation have comparable germicidal action. The prospects of a new bactericidal radiation source - XeBr-excilamp - are discussed.

The possibility of use of nonlinear ring interferometer (NRI) for protect of information was shown by the authors earlier. How does the mismatch of the principal physical factors influence error of deciphering in model of cryptosystme based on NRI? It appears that this error can be submitted as a wave process. The anlysistical expressions of amplitude and phase of this process are obtained. These expressions do not contradict results of author's simulations. A possibility of delay time cracking by means of correlation analysis and number of keys of stipulated by nonlinearity parameter variations is discussed.

This paper presents the results of experimental studies of the lifetime characteristics of exciplex lamps that contain molecular chlorine as a component of the gas mixture. It is established that the temperature of the quartz wall of the envelope has a substantial effect on the degradation of the working mix and that the wall rapidly loses transmittance in the UV at temperatures above 100°C. It is shown that the service life of excilamps is at least 3000h when a buffer volume is used in the envelope and when working mixtures are used in which the halogen concentration was higher than for the optimum emission of the working mix at medium power.