Light Negative Ions Research Articles

Evaluating the Parameters of a Systematic Long-Term Measurement of the Concentration and Mobility of Air Ions in the Environment inside Císařská Cave

Determining the concentration and mobility of light air ions is an indispensable task to ensure the successful performance and progress of various operations within multiple fields and branches of human activity. This article discusses a novel methodology for measuring air ions in an environment with high relative humidity, such as that of a cave. Compared to common techniques, the proposed method exhibits a lower standard deviation and analyses the causes of spurious oscillations in the measured patterns obtained from FEM-based numerical simulations on the one hand and a model with concentrated parameters on the other. The designed ion meter utilises a gerdien tube to facilitate long-term measurement in cold and very humid spaces, an operation that can be very problematic if executed with other devices. Importantly, the applied procedure for calculating the mobility spectra of air ions from the acquired saturation characteristics is insensitive to fluctuations and noises in the measured patterns, and it also enables us to confirm the presence of very mobile air ions generated by fragmenting water droplets. During the sensing cycles, the concentration of light negative ions was influenced by the active gerdien tube. For the investigated cave, we had designed a measuring sequence to cover not only the time dependence of the concentration of light negative ions but also their mobility; this approach then allowed monitoring the corresponding impact of the patients’ presence in the cave, an effect neither described nor resolved thus far. Such comprehensive research, especially due to its specific character, has not been frequently conducted or widely discussed in the literature; the efforts characterised herein have therefore expanded the relevant knowledge and methodology, thus contributing towards further advancement in the field.

THE USE OF POTASSIUM SALTS UNIQUE PROPERTIES FOR SUPPRESSION OF POTATO PATHOGENS DURING STORAGE PERIOD

Natural sylvinite has the property to produce light air ions due to air molecules contact with potassium and sodium cations. Such environment has the ability to inhibit the growth of potato pathogens. In given report the results of different methods of medium saturation with light negative ions are presented. The studied treatments were following: the surface from bulk sylvinite; aerosol generator (blowing air through salt filters). The filters with lumpy sylvinite filling and special pills from pressed sylvinite were used. Various modes of airing regimes were evaluated – three and six hours a day. The safety of tubers for the storage period, as well as the qualitative set of potato pathogens were assessed. The least number of infected tubers was noted in treatments with “pill”salt filter with three hours ventilation regime and the surface from bulk sylvinite (0.56 and 0.57%, respectively), the largest number of diseased tubers - in the control variant - 1.18%. The smallest mass loss of tubers in the period from January 29 to April 14 was recorded in the treatment with pill salt filter with with three hours ventilation regime - 1.53%, the maximum loss - when using a surface from bulk sylvinite - 2.9%. After studies in typical storages equipped with standard ventilation systems, a technology for potato storage, based on the creation favorable air environment saturated with negative air ions and saline aerosol, will be developed.

СТАНОВЛЕНИЕ И РАЗВИТИЕ СПЕЛЕОТЕРАПИИ В МИРОВОЙ ПРАКТИКЕ

Speleotherapy (ST) is a non-drug method of treatment which uses the microclimate of underground spaces. Such spaces may be represented by karst caves, salt mines, rock-salt and metal mine workings. The specific environment of underground spaces is the main factor affecting the patient's body. Speleoenvironment is formed by the combination of medical and health-improving components. Microfine salt aerosol is the main component of the speleoenvironment. It is based on the light negative ions arising at high levels of air ionization. The other components of the speleoenvironment are the constancy of the microclimate, temperature background, humidity, air flow rate. Another important factors are the absence of allergens and low bacterial contamination. Shielding effect ot the underground space, protecting from the exposure to radio-magnetic radiation is also mentioned. The main stages of the formation and development of the ST method in the world practice are also discussed in the article. Various types of speleological hospitals and the peculiarities of their geographic location are described. The factors of the speleoenvironment are presented. These factors affect the patient's body if the method is used under various conditions.

On the nonlinear dynamics of breathers waves in electronegative plasmas with Maxwellian negative ions

Theoretical investigations depending on the observation data are carried out for the nonlinear amplitude modulation of ion-acoustic waves propagating in an unmagnetized plasma composed of Maxwellian electrons and light negative ions in addition to mobile cold positive ions. The basic set of fluid equations is reduced to a nonlinear Schrödinger equation (NLSE) for describing the modulational instability process. The regions of the stable and unstable wavepackets have been confined precisely for various regimes. Moreover, the criteria for the existence of the breathers have been obtained. Analytical solutions of the NLSE in the forms of Akhmediev breathers, Kuznetsov-Ma (KM) solitons, and rogue waves are obtained. The characteristics of the profile of Akhmediev breathers, KM solitons, and freak waves are examined depending on the relevant physical parameters of the observed data.

Measuring Light Air Ions in a Speleotherapeutic Cave

Abstract The paper deals with a methodology proposed for measuring the concentration of air ions in the environment of speleotherapeutic caves, and with the implementation of the AK-UTEE-v2 ionmeter. Speleotherapy, in the context of its general definition, is the medical therapy that utilizes the climate of selected caves to treat patients with health problems such as asthma. These spaces are characterized by the presence of high air humidity and they make extreme demands on the execution of the measuring device, the Gerdien tube (GT in the following) in particular, and on the amplifier electronics. The result is an automated measuring system using a GT with low-volume air flow, enabling long-term measuring of air ion concentration and determination of spectral ion characteristics. Interesting from the instrumentation viewpoint are the GT design, active shielding, and execution of the electrometric amplifier. A specific method for the calculation of spectral ion characteristics and the mode of automatic calibration were proposed and a procedure of automatic measurement in the absence of attendants was set up. The measuring system is designed for studying and long-term monitoring of the concentration of light negative ions in dependence on climatic conditions and on the mobility of ions occurring in the cave.

Chemical composition of SF6 low-pressure plasma in magnetic field

The chemical composition of a low-pressure SF6 plasma in a homogeneous magnetic field is studied using a one-dimensional fluid model. This model takes into account the magnetization of electrons and light negative ions F−. The influence of different parameters such as gas pressure, heating power and magnetic field strength is studied within a parameter range of interest for negative ion sources. The scheme of plasma chemical reactions is analysed in order to identify the main reactions responsible for the generation and decay of plasma species. This sensitivity analysis shows that the scheme of reactions can be significantly simplified.

The influence of negative ionization of the air on motor activity in Syrian hamsters (Mesocricetus auratus Waterhouse) in light conditions.

The motor activity of Syrian hamsters (Mesocricetus auratus Waterhouse) under the influence of negative ionization of the atmosphere applied for 10, 20 or 30 min per day was investigated. An ionizer with output of 14,000 light negative ions per 1 cm3 of air was used. Studies carried out in the light phase of a 12:12 h light/dark regime revealed a relation between the reaction of the animal and the time of day at which ionization was applied. Ionization for 20 or 30 min in the light phase decreased motor activity, while 10 min of ionization increased it compared to control animals. Ionization in the dark phase gave a more distinct rise in activity than that applied in the light phase for all three durations of ionization.

Neutralization of multi-MeV light negative ions by plasma neutralizers

A hollow cathode discharge fed plasma neutralizer has been built and was used to neutralize 3-MeV Li−, C−, and Si− ions. Initial results indicate that the performance of an unoptimized plasma neutralizer is better than gas stripping. Since hollow cathodes produce plasma targets with high efficiency, this type of plasma neutralizer can improve the overall efficiency of a neutral beam line.

Efficiencies of gas neutralizers for multi-MeV beams of light negative ions

We report measurements of the neutral and charged particle fractions produced by running beams of Li−, C−, O−, and Si− at energies up to 7 MeV through gas cells of N2, Ar, or CO2. We discuss the implications of these measurements for the design of neutralizers to produce high-energy light atom beams for heating or current drive in tokamaks.

The formation of negative ions by positive-ion impact on surfaces

The quantal theory of negative ions has now been developed considerably (Massey and Smith 1936; Massey 1938), but on account of difficulties of computing it is usually necessary to assume rather than to prove that a given ion exists, and then to discuss the probability of its formation by different processes. The work described here is a contribution to the experimental side of this subject. It had its origin in a projected attempt to measure the capture cross-section of mercury atoms for electrons, as a verification of Massey and Smith's (1936) then unpublished theory of this process. In considering this it became clear that the experiment would be one of unusual difficulty. Before proceeding with it, therefore, it was decided to verify the existence of Hg - as a stable entity, which is assumed in the quantal theory. this was in doubt since Stille (1933), in some careful experiments, had recently failed to obtain it from the plasma of various forms of discharge through mercury vapour, although it is known that negative ions tend to accumulate in such regions (Emeleus and Sayers 1938). Whilst one of us was repeating his experiments, with modifications which led to essentially the same results and will be describes elsewhere, Arnot and Milligan (1936 b ) reported that they had obtained Hg - by bombardment of metal surfaces with Hg + . A comparison of their work with our own showed only one essential point of difference, namely that the construction of their apparatus did not permit of degassing in situ , a condition satisfied with our tubes. Both for this reason and because of the intrinsic importance of their discovery it was thought desirable to repeat part of their work, with apparatus geometrically similar in electrode construction, but capable of being degassed in a furnace under vacuum. We were again unable to obtain Hg - after the apparatus had been degassed and in operation for a short of that of Hg - was obtained. There were, however, always present several light negative ions, which had the excess energies found by Arnot and Milligan (1936 b ) with Hg - . The conditions under which these were formed led us to suppose that they were produced by bombardment of the metal surfaces by mercury positive ions (Press 1937; Sloane 1937) and not capture of electrons by positive ions of the same species, the process suggested by Arnot and Milligan (1936 b ). The existence of a process of this type, which may be conveniently termed "sputtering" (Sloane and Press 1938), is also implied by some earlier work by J. S. Thompson (1931) which has, so far as we know, never been published in detail. It is, however, impossible to decide definitely ion (e. g. CO - ) when it hits the surface, so long as one is producing the negative ions on a metal surface in a plasma or ionization chamber. One cannot overlook the possibility of the negative ion being formed from its own positive ion, since the latter may be present in the plasma or ionization chamber, and CO + , for example, was in fact shown in our work to be there from the positive-ion mass spectra, although in quantity only a fraction of 1% of Hg + . An unambiguous decision on this point can only be reached by first isolating a particular positive ion by a mass spectrograph, then bombarding a surface by this in a high vacuum , and finally making a mass spectrographic and energy distribution analysis of the resultant negative ions. We have built a double mass spectrograph for this purpose and find that negative ions of one kind possessing energies in excess of that imparted to them by the accelerating fields can be produced by bombardment with positive ions of another kind (Sloane and Press 1938). An account of the experiments with the single mass spectrograph is given in 1. the experiments with the double mass spectrograph are described in 2.