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Among the physicochemical properties of drugs, dissociation constant (pKa) is the most important parameter for the design and development of new and existing drug molecules. We report for the first time, the experimental determination of dissociation constant (pKa) for a frontline anti-tubercular drug isoniazid. Besides, pKa values of the two of its newly synthesized sulfonyl derivatives, N′-[(2,4,6-trimethylbenzene)sulfonyl]pyridine-4-carbohydrazide (SZ-I), N′-[(4-bromobenzene)sulfonyl]pyridine-4-carbohydrazide (SZ-II) were also determined. The approach adopted was UV–Visible spectrophotometry which is an established analytical method known for its accuracy and reproducibility. The spectrophotometric analysis was performed by measuring the absorbance values at various pH and the pKa values were then calculated using Henderson-Hasselbalch equation. The pKa values were found to be 3.0, 3.55 and 3.43 for Isoniazid (INH) and its sulfonyl derivatives SZ-I and SZ-II, respectively. [ABSTRACT FROM AUTHOR]

In this work, we discuss the effects of component ratios on plasma characteristics, chemistry of active species, and silicon etching kinetics in CF4 + O2, CHF3 + O2, and C4F8 + O2 gas mixtures. It was shown that the addition of O2 changes electrons- and ions-related plasma parameters rapidly suppresses densities of CFx radicals and influences F atoms kinetics through their formation rate and/or loss frequency. The dominant Si etching mechanism in all three cases is the chemical interaction with F atoms featured by the nonconstant reaction probability. The latter reflects both the remaining amount of fluorocarbon polymer and oxidation of silicon surface. [ABSTRACT FROM AUTHOR]

Multi-parameter study on the subsonic equilibrium air plasma flows in the cylindrical discharge channel of an induction RF-plasmatron IPG-3 with the maximum operating power of 1 MW is presented. Simulations are carried out by numerical solution of full Navier–Stokes equations coupled with a two-dimensional equation for high-frequency electric field; the discretization of the equations is performed on a staggered Cartesian mesh. An effective method for calculation of the transport coefficients for ionized multi-component air (including the plasma conductivity) in the temperature range 300–15000 K is applied, with the higher-order approximations by the Sonine polynomial in the Chapman–Enskog method. Simulation results are presented, including the flow fields, electric field, and thermodynamic parameters of the air plasma in the discharge channel of a high-power induction plasmatron. The results obtained reveal for the first time the structure and parameters of a plasma torch in a large-diameter (200 mm) discharge channel at powers up to 300 kW, providing the axial specific enthalpies at the channel outlet as high as 68 MJ/kg. [ABSTRACT FROM AUTHOR]

We use the large spectroscopic data set of the MOSFIRE Deep Evolution Field survey to investigate some of the key factors responsible for the elevated ionization parameters (U) inferred for high-redshift galaxies, focusing in particular on the role of star-formation-rate surface density (ΣSFR). Using a sample of 317 galaxies with spectroscopic redshifts z spec ≃ 1.9–3.7, we construct composite rest-frame optical spectra in bins of ΣSFR and infer electron densities, n e, using the ratio of the [O ii ] λ λ 3727, 3730 doublet. Our analysis suggests a significant (≃3 σ) correlation between n e and ΣSFR. We further find significant correlations between U and ΣSFR for composite spectra of a subsample of 113 galaxies, and for a smaller sample of 25 individual galaxies with inferences of U. The increase in n e—and possibly also the volume filling factor of dense clumps in H ii regions—with ΣSFR appear to be important factors in explaining the relationship between U and ΣSFR. Further, the increase in n e and SFR with redshift at a fixed stellar mass can account for most of the redshift evolution of U. These results suggest that the gas density, which sets n e and the overall level of star formation activity, may play a more important role than metallicity evolution in explaining the elevated ionization parameters of high-redshift galaxies. [ABSTRACT FROM AUTHOR]

Bioaccumulation of ionizable pharmaceuticals has been increasingly studied, with most reported aquatic tissue concentrations in field or laboratory experiments being from fish. However, higher levels of antidepressants have been observed in bivalves compared with fish from effluent‐dominated and dependent surface waters. Such observations may be important for biodiversity because approximately 70% of freshwater bivalves in North America are considered to be vulnerable to extinction. Because experimental bioaccumulation information for freshwater bivalves is lacking, we examined accumulation dynamics in the freshwater pondmussel, Sagittunio subrostratus, following exposure to a model weak acid, acetaminophen (mean (±SD) = 4.9 ± 1 µg L–1), and a model weak base, sertraline (mean (±SD) = 1.1 ± 1.1 µg L–1) during 14‐day uptake and 7‐day depuration experiments. Pharmaceutical concentrations were analyzed in water and tissue using isotope dilution liquid chromatography–tandem mass spectrometry. Mussels accumulated two orders of magnitude higher concentrations of sertraline (31.7 ± 9.4 µg g–1) compared to acetaminophen (0.3 ± 0.1 µg g–1). Ratio and kinetic‐based bioaccumulation factors of 28,836.4 (L kg–1) and 34.9 (L kg–1) were calculated for sertraline and for acetaminophen at 65.3 (L kg–1) and 0.13 (L kg–1), respectively. However, after 14 days sertraline did not reach steady‐state concentrations, although it was readily eliminated by S. subrostratus. Acetaminophen rapidly reached steady‐state conditions but was not depurated over a 7‐day period. Future bioaccumulation studies of ionizable pharmaceuticals in freshwater bivalves appear warranted. Environ Toxicol Chem 2023;42:1183–1189. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

The ionization of sputtered species in high power impulse magnetron sputtering of titanium, chromium, and aluminum targets is analyzed using Abel-inverted spectroscopic imaging to locate the position of ionization. From the spatial emission of neutrals, it is deduced that most of the sputtered titanium particles become ionized within 0.5 mm distance from the target, whereas sputtered aluminum or chromium can travel much further through the discharge before ionization occurs. Probe measurements reveal the reason for this difference to be the unusually high electron temperature of around 4.5 eV for titanium compared to 2.6 eV and 1.5 eV for aluminum and chromium as the target material, respectively. These probe measurements are then compared to a global model derived from the ionization region model. Excellent agreement between model and measurements can be reached, but only if the transport physics for the confinement of the species is adjusted. Using the model, the difference between the three discharges can be traced back to be mostly caused by the sputter yield. Thus, we propose that ionization in discharges with low-yield materials should generally be expected to occur closer to the target surface, leading the ions to be affected more strongly by the electric field across the magnetic trap region, resulting in a more severe deposition rate loss compared to high-yield materials. [ABSTRACT FROM AUTHOR]

The structure and evolution of wind-blown bubbles (WBBs) around massive stars has primarily been investigated using an energy-conserving model of wind-blown bubbles. While this model is useful in explaining the general properties of the evolution, several problems remain, including inconsistencies between observed wind luminosities and those derived using this formulation. Major difficulties include the low X-ray temperature and X-ray luminosity, compared to the model. In this paper, we re-examine the evolution, dynamics, and kinematics of WBBs around massive stars, using published ionization gasdynamic simulations of wind-blown bubbles. We show that WBBs can cool efficiently due to the presence of various instabilities and turbulence within the bubble. The expansion of WBBs is more consistent with a momentum-conserving solution, rather than an energy-conserving solution. This compares well with the dynamics and kinematics of observed wind bubbles. Despite the cooling of the bubble, the shocked wind temperature is not reduced to the observed values. We argue that the X-ray emission arise mainly from clumps and filaments within the hot shocked wind region, with temperatures just above 106 K. The remainder of the plasma can contribute to a lesser extent. [ABSTRACT FROM AUTHOR]

In order to study the effect of inorganic salt additives on the surface tension of a sodium dodecylbenzene sulfonate (SDBS) solution, the surface tension of the mixed system of six common inorganic salt additives, NaCl, CaCl2, AlCl3, Na2SO4, Na2CO3, and NaHCO3, and SDBS was measured, and the effects of the inorganic salt types, surfactant concentrations and inorganic salt concentrations on the surface tension of the SDBS solution were studied. On this basis, three inorganic salts, NaCl, CaCl2 and Na2SO4, were selected, and their effects on the critical micelle concentration (CMC) of the SDBS solution were studied. The experimental results showed that different inorganic salts had different effects on the surface tension of the SDBS solution. The order of effect of the six inorganic salts on the surface tension of the SDBS solution was CaCl2 > NaCl > Na2SO4 > NaHCO3 > Na2CO3 > AlCl3; when the mass fraction of the SDBS solution is high, the influence of the inorganic salts on the surface tension of the SDBS solution is relatively small; with an increase in the concentration of the preferred inorganic salt additives, the surface tension of the SDBS solution decreases first, then tends to be stable, and then increases; a reduction in the critical micelle concentration by the three selected inorganic salt additives shows the trend of 0.7% NaCl > 0.5% CaCl2 > 0.5% Na2SO4. [ABSTRACT FROM AUTHOR]

Electron collision cross section data are complied from the literature for electron collisions with the nitrogen molecules, N2, N 2 + , and N 2 * . Cross sections are collected and reviewed for total scattering, elastic scattering, momentum transfer, rotational excitation, vibrational excitation, electronic excitation, dissociative processes, and ionization. The literature has been surveyed up to the end of 2021. For each of these processes, the recommended values of the cross sections are presented. [ABSTRACT FROM AUTHOR]

An experiment was conducted at Sam Higginbottom University of Agriculture Technology And Sciences, Allahabad in the year 2017-2018 to check the effect of different doses of Gamma radiation (0kR, 1.5kR, 3kR, 4.5kR, and 6kR) on corms of three different gladiolus cultivars namely Praha, Tiger flame, and Snow Princess, it was established that till 3 kR most of the characters were stimulated but started to sink from 4.5kR. However, 6kR treated corms produced leathery and narrower leaves with shorter plant height (57.41 cm), less leaf number (6.75), less sprouts/corm (1.57), and least spikes/plant (1.14) with an abnormal spike. While 1.5 kR treatment proved the most beneficial for various growth parameters including Plant height (87.21cm), the number of leaves (10.76), early sprouting (14.40 days), Early flowering (72.37 days), Longest flower spike (75.41 cm) and more spikes per plant (2.90). Among the Cultivars Tiger flame and Praha were found to respond well to lower doses of gamma radiation and consider being more suitable for gamma treatment. Moreover, discolor basal floret was found in Praha in 1.5kR treated corms, and Chimera was found on Tiger Flame variety at 3kR. [ABSTRACT FROM AUTHOR]

Используя лидарные сигналы на длинах волн 561 и 532 нм в диапазоне высот 30-400 км, путем решения обратной задачи восстанавливаем коэффициенты рассеяния света, соответствующие этим длинам волн, что позволяет сравнить оптические характеристики термосферы, мезосферы и верхней стратосферы и определить соотношения между резонансным, рэлеевским и аэрозольным рассеянием света на разных высотах атмосферы. Используя коэффициенты рассеяния в термосфере, находим сечения рассеяния света на длинах волн 561 и 532 нм переходов возбужденных атомарных ионов кислорода и азота и объясняем, почему коэффициенты рассеяния для O+, 561 нм меньше чем для N+, 532 нм, в то время как концентрация O+ на два порядка выше чем N+. Полученные здесь результаты представляют интерес для понимания ионизационного эффекта солнечной активности на оптические характеристики атмосферы, которые определяют погодные и климатические изменения.

The paper presents the results of experiments with electroflotation beneficiation of gold-bearing raw materials. Three variants of ore samples with 0.56, 1.2 and 5.9 g/t gold grades, which also have different mineralogical and phase composition, were taken as objects of study. Based on the ionization effects, as well as changes in electrostatic and electrokinetic properties of the flotation pulp components, different electrode locations in the flotation chamber were considered. Experiments have shown that for electroflotation processing of raw materials with weakly acidic and neutral medium, positive electric potential of pulp, as well as raw materials with complex mineralogical composition, the negative electrode (cathode) should be placed at the surface of foaming and concentrate assembly, and the positive electrode (anode) in the pulp flow. For electroflotation of raw materials with neutral, alkaline pH and negative electric potential of the pulp, the anode is placed at the surface of the concentrate formation and the cathode is placed in the pulp flow. Thus, additional electrolytic treatment of mineral slurry in the flotation process can increase the gold recovery in the flotation concentrate by an average of 20-30 %.

In this study, an online solid-phase extraction-thermal desorption method coupled with gas chromatography-flame ionization detection was used to extract seven pyrethroids from tap water and agricultural wastewater. For this purpose, a metal-organic framework MIL-101(Cr) was synthesized, and its applicability as a solid-phase sorbent was studied. Several effective parameters of the extraction efficiency such as the amount of sorbent, sample volume, sample pH, and thermal desorption procedure were also explored. Moreover, molecular docking was used to predict and assess the nature of pyrethroids adsorption on MIL-101(Cr). Additionally, the molecular interactions and the binding energies were studied and calculated. The analytical performance of the proposed method showed an excellent linear dynamic range (r = 0.9953-0.9997) for pyrethroids in the range of 0.5-10 [mu]g/L and relative standard deviations less than 8.3% combined with satisfactory detection and quantification limits (below 0.20 and 0.9 [micro]g/L, respectively). Under the optimal conditions, the method was successfully applied for the determination of pyrethroids in real samples (tap water and wastewater) with satisfactory recoveries in the range of 85.1-97.2%., Author(s): Mahsa Torabizadeh [sup.1], Kourosh Tabar-Heydar [sup.1], Seyyed Hamid Ahmadi [sup.1] Author Affiliations: (1) grid.466618.b, 0000 0004 0405 6503, Faculty of Clean Technologies, Chemistry and Chemical Engineering Research Center of [...]

The effect of collisions, ionisation and non-extensivity is studied numerically in an electronegative warm plasma associated with electron emission from the wall. Electrostatic potential, space charge density, net negative charge density and emitted electron beam density are plotted with the normalised distance to see the effects of aforesaid parameters The negative ion is described with fluid equations to see it's effect of the mass ratio (negative ion to positive ion) on emitted electron beam density inside the sheath. The three types of electronegative plasma taken are CF4, O2 and C60. The emitted beam electron density is more in number at the wall for higher collisional and ionisation case and less in higher mass ratio. For super-extensive case the emitted beam electrons is lesser than compared to the Boltzmann distributed electrons. The sheath thickness is found to be more in higher mass ratio, emitted beam electrons and super -extensive case while for higher collisional and ionisation case the sheath thickness is less. [ABSTRACT FROM AUTHOR]

Over the last decade, it has become clear that for heavy ion projectiles, the projectile's transverse coherence length must be considered in theoretical models. While traditional scattering theory often assumes that the projectile has an infinite coherence length, many studies have demonstrated that the effect of projectile coherence cannot be ignored, even when the projectile-target interaction is within the perturbative regime. This has led to a surge in studies that examine the effects of the projectile's coherence length. Heavy-ion collisions are particularly well-suited to this because the projectile's momentum can be large, leading to a small deBroglie wavelength. In contrast, electron projectiles that have larger deBroglie wavelengths and coherence effects can usually be safely ignored. However, the recent demonstration of sculpted electron wave packets opens the door to studying projectile coherence effects in electron-impact collisions. We report here theoretical triple differential cross-sections (TDCSs) for the electron-impact ionization of helium using Bessel and Laguerre-Gauss projectiles. We show that the projectile's transverse coherence length affects the shape and magnitude of the TDCSs and that the atomic target's position within the projectile beam plays a significant role in the probability of ionization. We also demonstrate that projectiles with large coherence lengths result in cross-sections that more closely resemble their fully coherent counterparts. [ABSTRACT FROM AUTHOR]

Ionic porous organic polymer (i-POP) is an emerging class of organic porous polyelectrolytes featuring ionized backbones or side groups on the skeletons. i-POPs are highly designable exhibiting large specific surface areas and intrinsic nanopores. Their physicochemical properties and functionality can be skillfully regulated by varying ionized building blocks. Compared with neutral porous organic polymers, i-POPs possess controllable ionic sites and high charge density, broadening the application ranges of porous organic polymers. Meanwhile, their applicability can be strengthened by the inherent association between pore confinement, skeleton function, and abundant ionic sites. The compositions, structures, and synthetic methods of amorphous i-POPs have been significantly explored in recent years. Tremendous studies have demonstrated that i-POPs are promising for various advanced applications including adsorption/separation, sensing, catalysis and so on. [ABSTRACT FROM AUTHOR]

The parameters of the gas phase and the kinetics of reactive ion etching of SiO2 and Si3N4 under conditions of an induction RF (13.56 MHz) discharge with a varying HBr/Cl2 ratio is studied. The study includes plasma diagnostics using Langmuir probes, plasma modeling to find stationary concentrations of active particles, measuring velocities, and analyzing etching mechanisms in the effective interaction probability approximation. It is found that the substitution of HBr by Cl2 at a constant argon content (a) is accompanied by a noticeable change in the electrical parameters of the plasma; (b) leads to a weak increase in the intensity of ion bombardment of the treated surface; and (c) causes a significant increase in the total concentration and flux density of reactive particles. It is shown that the etching rates of SiO2 and Si3N4 increase monotonically as the proportion of Cl2 increases in a mixture, while the main etching mechanism is an ion-stimulated chemical reaction. The model description of the kinetics of such a reaction in the first approximation assumes (a) the additive contribution of bromine and chlorine atoms and (b) the direct proportional dependence of their effective interaction probabilities on the intensity of ion bombardment. The existence of an additional channel of heterogeneous interaction with the participation of HCl molecules is proposed. [ABSTRACT FROM AUTHOR]

We present ionization cross-sections for antiproton and helium collisions based on an ab initio time-dependent coupled channel method. In our calculations, a finite basis set of regular helium Coulomb wave packets and Slater function were used. The semiclassical approximation was applied with the time-dependent Coulomb potential to describe the antiproton–electron interaction. Three different projectile energies were considered as 10, 50 and 100 keV. We found clear evidence for the formation of the anti-cusp in the differential distributions. [ABSTRACT FROM AUTHOR]

We theoretically investigated the properties of the ultraviolet secondary radiation generated under the action of three-color ionizing pulses obtained from parametric light generators. We show that the combination components in the spectrum of electron currents generated under the action of such three-color pulses can form a strictly exponentially decreasing sequence. For moderately short pump pulse durations (30 fs at 800 nm main field) with the use of this effect, it is possible to generate a smooth broadband supercontinuum in the 800–100 nm range. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is essential for assessing shoulder conditions. This study aimed to evaluate current shoulder MRI practices in Jordan, including technical parameter patterns, and determine if they adhere to the American College of Radiology (ACR) guidelines. The retrospective analysis included data from 48 eligible participants from 13 MRI centers in March 2021. Descriptive and correlation data analysis were performed using IBM SPSS statistics version_20 and Excel 2013. Most MRI centers (50%) were private outpatient clinics with closed MRI machines above 1 Tesla. Most participants (62.5%) were male, and shoulder pain (47.9%) was the main clinical indication. Most shoulder orientations (68.7%, 33/48) were right shoulders, and the coronal MRI planes (43%, 121/280) were the most common. The alignment percentage for the axial plane was 100%, but MRI artifacts of the shoulder were present in 8.2% of cases (23/280). Dark fluid T1-W coronal sequence was not conducted in 25% of the cases. The percentage of the field view (FOV) within ACR recommendations was 45% (126/281), and slice thickness parameters were 96% (269/281). The recommended pixel area for all sequences was 47.9% (134/280), encompassing all axial, sagittal oblique, and coronal planes. However, crucial parameters, such as FOV and slice thickness, were inadequate and did not meet the ACR guidelines, resulting in suboptimal image quality of shoulder MRI. To improve MRI image quality, it is recommended that MRI technologists receive ongoing education and training on appropriate MRI image parameters. [ABSTRACT FROM AUTHOR]

Although copper‐silver ionization (CSI) has been used for 30 years to inactivate Legionella bacteria and other opportunistic pathogens in water, the literature is a mix of both successes and failures. This paper reviews the technology and case studies to help improve the success of CSI installations. Important is a properly designed system capable of consistent delivery of copper/silver ions at their target levels. However, even the most advanced system will fail if not properly operated and maintained. Water chemistry can impact the performance of CSI systems and attention should be on conductivity, temperature, oxygen, flow, pH, chloride, sulfate, alkalinity, hardness, phosphate and dissolved organic carbon levels. Several case studies are provided to demonstrate the effectiveness of CSI treatment even at high pH levels. The report concludes that the use of CSI to control Legionella and other opportunistic pathogens is highly effective when the units are properly designed, maintained, and operated. [ABSTRACT FROM AUTHOR]

Our study has shown that in collisions p-He and p-Ar with energies above 50 keV fast electrons carry away as kinetic energy up to 70 % of energy released during particle stopping. Ignoring the fast electron contribution makes impossible bringing independently measured cross sections of elementary processes of ionization, excitation, stripping and charge exchange into compliance with measured cross sections of electronic stopping. Fast electron emission in collisions of energetic ions with solids may induce extra radiation effects (create additional vacancies and defects in solid). Mean kinetic energies of ejected electrons W e obtained from the analysis of cross section ratio agree well with directly measured energy spectra of the emitted electrons. The dynamic ionization theory implies the W e proportionality to initial velocity v. In the considered cases, such a dependence takes place at the velocities below 2 a.u. At higher velocities, the observed dependence is successfully described in the framework of the Born approximation. [ABSTRACT FROM AUTHOR]

Environmental pollution caused by human activities, the harmful mixture of gases (CO, CO2, NO2, SO2, PM), resulting from industrial production processes and vehicular traffic is a global environmental health problem in urban and rural areas; it affects vulnerable groups, children and older adults, affecting respiratory, cardiovascular and cancerous diseases. In Ecuador, in the city of Cuenca, among the main sources of contamination is the vehicle fleet in high-traffic areas and avenues; in addition to the industrial zone, that coexists with the city within the urban area in the northwest zone, which generates contamination to properties located around these strips. This paper presents the development of a purifying element based on the "evolutionary development" model. It begins by analyzing and studying concepts of lattices, ionization, and air purification, among others; subsequently, existing air purification systems are investigated in detail and a prototype of an ionizing lattice is generated, whose function is to filter polluted air when installed as an aesthetic part in buildings. Finally, the purification performance of gases and particles typical of the electrostatic precipitator (ESP) was tested by means of air quality stations. By means of a type of correlational applied research, the similarity between external and internal gases and particulate matter was verified, obtaining, as a result, the effective reduction of the same; decreasing by 4.15% of CO2, 30% of CO and 57% of particulate matter. With this analysis, it is concluded that the prototype of the ionization air purifying lattice can be efficient with some of the gases against particulate pollution in domestic interiors, positively influencing the health of the inhabitants of a building. [ABSTRACT FROM AUTHOR]

It is generally assumed that ionization in slow collisions of light atomic particles, whose constituents (electrons and nuclei) move with velocities orders of magnitude smaller than the speed of light, is driven solely by the Coulomb force. Here we show, however, that the Breit interaction—a relativistic correction to the Coulomb interaction between electrons—can become the main actor when the colliding system couples resonantly to the quantum radiation field. Our results demonstrate that this ionization mechanism can be very efficient in various not too dense physical environments, including stellar plasmas and atomic beams propagating in gases.

Cosmic rays (CRs) are the primary driver of ionization in star-forming molecular clouds (MCs). Despite their potential impacts on gas dynamics and chemistry, no simulations of star cluster formation following the creation of individual stars have included explicit cosmic-ray transport (CRT) to date. We conduct the first numerical simulations following the collapse of a 2000 M _⊙ MC and the subsequent star formation including CRT using the STAR FORmation in Gaseous Environments framework implemented in the GIZMO code. We show that when CRT is streaming-dominated, the CR energy in the cloud is strongly attenuated due to energy losses from the streaming instability. Consequently, in a Milky Way–like environment the median CR ionization rate in the cloud is low ( ζ ≲ 2 × 10 ^−19 s ^−1 ) during the main star-forming epoch of the calculation and the impact of CRs on the star formation in the cloud is limited. However, in high-CR environments, the CR distribution in the cloud is elevated ( ζ ≲ 6 × 10 ^−18 ), and the relatively higher CR pressure outside the cloud causes slightly earlier cloud collapse and increases the star formation efficiency by 50% to ∼13%. The initial mass function is similar in all cases except with possible variations in a high-CR environment. Further studies are needed to explain the range of ionization rates observed in MCs and explore star formation in extreme CR environments.

Cosmic rays, including galactic cosmic rays and solar energetic particles, form the main source of ionization of the low and middle atmosphere, which is important for various chemical and physical effects in the atmosphere. Realistic models able to compute the cosmic-ray-induced ionization (CRII) are used as inputs for chemistry-climate models. One of the most commonly used atmospheric ionization models is CRAC:CRII (Cosmic-Ray Atmospheric Cascade: application to CRII) initially developed in 2004–2006 (version 1) and significantly improved in 2010–2011 (version 2). Here, a new updated version 3 of the CRAC:CRII model is presented which offers a higher accuracy for the middle-upper atmosphere and lower-energy cosmic rays. This is particularly important for studies of the atmospheric effects of solar particle storms. Detailed lookup tables of the ionization yield function are provided for the primary cosmic ray protons and α-particles (the latter representing also heavier cosmic-ray species) along with a practical recipe for their numerical use.

We recently found that streaming cosmic rays (CRs) induce a resistive electric field that can accelerate secondary electrons produced by CR ionization. In this work, we study the evolution of the energy spectrum of secondary electrons by numerically solving the one-dimensional Boltzmann equation and Ohm’s law. We show that the accelerated secondary electrons further ionize a gas, that is, an electron avalanche occurs, resulting in increased ionization and excitation of the gas. Although the resistive electric field becomes weaker than the one before the CR discharge, the weak resistive electric field weakly accelerates the secondary electrons. The quasi-steady state is almost independent of the initial resistive electric field but depends on the electron fraction in the gas. The resistive electric field in the quasi-steady state is larger for the higher electron fraction, which makes the number of secondary electrons that can ionize the gas larger, resulting in a higher ionization rate. The CR discharge could explain the high ionization rate that is observed in some molecular clouds.

The processes of single-electron charge exchange, excitation, and ionization during proton impact on H(2 l ) are investigated. We employ two different theoretical methods that are suitable for different collision energy regions: the full quantum-mechanical molecular orbital close-coupling method for energies from 0.001 to 1 keV u ^−1 and the two-center atomic orbital close-coupling (TC-AOCC) method for energies between 0.3 and 100 keV u ^−1 . For charge exchange and excitation processes, the total and nl -resolved cross sections to the final reaction channels of H ( nl , n = 1–4) have been obtained over a broad energy region. Moreover, the ionization cross sections in the TC-AOCC calculation are also reported for both H(2 s ) and H(2 p ) initial target states. The present results are all compared with those from other sources when available. It is found that the magnitude and energy behavior of nl -resolved excitation cross sections for H ^+ –H(2 p ) collisions are significantly distinct from those of the H(2 s ) initial state in the entire energy range considered, particularly in the low-energy region. The energy behaviors of the nl -resolved charge exchange cross sections from the H(2 p ) initial state are similar to those from the H(2 s ) initial state, but their magnitudes are larger. The present accurate cross-section data are anticipated to provide insight into the research of astrophysics and controlled fusion plasmas.

The solar ultraviolet intensities of spectral lines originating from Li- and Na-like ions have been observed to surpass the expectations derived from plasmas with coronal approximation. The violation of the coronal approximation can be partially attributed to nonequilibrium ionization (NEI) due to dynamic processes occurring in the vicinity of the transition region. To investigate the impact of these dynamics in the Alfvén wave-heated coronal loop, a set of equations governing NEI for multiple ion species was solved numerically in conjunction with 1.5-dimensional magnetohydrodynamic equations. Following the injection of Alfvén waves from the photosphere, the system undergoes a time evolution characterized by phases of evaporation, condensation, and quasi-steady states. During the evaporation phase, the ionization fractions of Li- and Na-like ions were observed to increase when compared to the fractions in ionization equilibrium, which led to an enhancement in the intensity of up to 1.6. This over-fractionation of Li- and Na-like ions was found to be induced by the evaporation process. While collisions between shocks and the transition region temporarily led to deviations from ionization equilibrium, on average over time, these deviations were negligible. Conversely, under-fractions of the ionization fraction led to a reduction in intensity down to 0.9 during the condensation phase and the quasi-steady state. Given the dependency of the over/under-fractionation on mass circulations between the chromosphere and the corona, these observations will serve as valuable benchmarks to validate not only Alfvén wave models but also other existing mechanisms on coronal heating.

An initial theoretical attempt to explain the observed decrease of the polytropic/adiabatic index γ in the solar corona has been accomplished. The chemical reactions of the ionization–recombination processes in local thermodynamic equilibrium (LTE) of a solar plasma cocktail containing heavy elements are found to cause 1.1 < γ ≤ 5/3 in the quiet solar atmosphere. It is also shown that the quiet solar atmosphere is in LTE, justifying this theoretical study. This result is obtained by numerically solving the Saha equation and subsequently using a newly derived equation for calculation of the polytropic index from thermodynamic partial derivatives of the enthalpy and pressure with respect to density and temperature. In addition, a comparison measured from spectroscopic observations of propagating slow magnetohydrodynamic waves in coronal loops shows that LTE ionization accounts for a very small part of the observed decrease of γ , meaning that the solar plasma in the active region is not in LTE as expected. However, the observed dependency of higher polytropic index at higher temperatures is confirmed by the current theoretical approach. It is concluded that in order to account for the polytropic index decrease in the active regions of the solar corona, it is necessary for kinetic non-LTE ionization calculations to be performed.

Although the comparison of fully differential ionization data for particle and antiparticle impact provides the ultimate tests of theoretical models, only very low antiparticle beam intensities are available. Hence, few experiments of this type have been performed. Therefore, available experimentally obtained single and double differential cross-sections, which are much easier to obtain, are compared in order to demonstrate differences when only the projectile mass or charge (+1 or −1) is changed. Included in the comparison are cross-sections calculated for positron and electron impact using a three-particle classical trajectory Monte Carlo method. The calculated cross-sections provide independent information about the ejected electron and the scattered projectile contributions, plus information about the impact parameters, all as functions of the collision kinematics. From these comparisons, suggestions as to where future investigations are both feasible and useful are provided.

The food industry has recognized the importance of environmental sanitation, and fruit control, a renowned leader in controlled atmosphere, has invested in sanitation through the use of ionizers to eliminate microorganisms in agri-food environments. This report presents results of tests conducted on various products, both in experimental and real scenarios in fruit and vegetable distribution platforms, to evaluate the effectiveness of ionization on vegetable products. The report covers three different situations: the first two focused on the effects of ionization on radish and table grape cells, while the last test verified the impact of ionization on a distribution platform that processes and markets various types of fruits and vegetables, such as pepper, tropical fruits, blueberry, apples, pears, table grape, chicory, and more.