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Silicon photomultipliers (SiPMs) are solid-state, single-photon sensitive, pixelated sensors whose usage for scintillation detection has rapidly increased over the past decade. It is known that the avalanche process within the device, which renders a single photon detectable, can also generate secondary photons which may be detected by a separate device. This effect, known as external crosstalk, could potentially degrade the science goals of future xenon dark matter experiments. In this article, we measure the effect of external crosstalk in a dual-phase, liquid xenon time projection chamber fully instrumented with SiPMs. We then consider the implications for a future xenon dark matter experiment utilizing SiPMs and discuss possible solutions.

We present the angular distribution of the ejected electron for single ionization of He by fast proton impact. A four-body formalism of the three-Coulomb wave is applied to calculate the triple differential cross sections at several impact energies in the scattering, perpendicular and azimuthal planes. Moreover, the three-body formalism of three-Coulomb, two-Coulomb and first Born approximation models has also been used to study the many-body effect on electron emission and the validity of the models. In the three-Coulomb wave model, the final state wave function incorporates distortion due to the three-body mutual Coulombic interaction. In this formalism, we use an uncorrelated and correlated Born initial state, which consists of a plane wave for the incoming projectile times a two-electron bound state wavefunction of the helium atom representing the 1s2(1S) state. But, in the case of the three-body formalism, the initial state wavefunction consists of a long-range Coulomb distortion for the incoming projectile and one active electron of the He atom described by the Roothaan–Hartree–Fock wavefunction. The structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinematic conditions. In addition, the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He target. In the four-body formalism, the present computations are very fast by reducing a nine-dimensional integral to a two-dimensional real integral. Despite the simplicity and speed of the proposed quadrature, the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other theories. [ABSTRACT FROM AUTHOR]

Double-differential cross sections (DDCS) as a function of low-energy electron emission at different impact energies are calculated for the collisions of dressed ions with He atoms by using the four-body formalism of the three-Coulomb wave (3CW-4B) model. We report the energy distribution of ejected electrons with energies varying from 5 to 500 eV for different emission angles. In this work, a model potential is used to represent the interaction between the dressed projectile and the active electron of the target. This potential presents a short-range term and a Coulomb long-range term depending on the net charge of the projectile and the number of electrons bound to it. The nine-dimensional integrals for the transition amplitude are partly reduced to a two- and three-dimensional integrals, which can be easily calculated numerically. The present 3CW-4B results are compared with the available experimental data and other theoretical calculations. The results agree favorably well with the existing experimental findings, especially at high-impact energies. We also studied the dependence of the effective charge of the dressed projectile on the electron emission spectra. Furthermore, the DDCS has been calculated in a range of projectile scattering angles (0–2 mrad) along with electron energies (10–300 eV) and discussed the appearance of different structures. [ABSTRACT FROM AUTHOR]

The 2D code developed by the authors for calculating the penetration of neutral particles from the chamber wall to the center of the plasma created and confined in the L-2M stellarator has been verified. In the range of operating plasma densities (1 × 1019 m–3 < ne < 3 × 1019 m–3), good agreement with the results of calculations performed using the ASTRA code has been obtained. The 3D and 4D simulations of the penetration of neutral particles from the chamber wall to the central plasma region have been performed. It has been shown that the 2D simulations overestimate the concentration of neutral particles in the plasma central region, as compared to the 3D and 4D models, which use ion velocity distributions closer to the real one. [ABSTRACT FROM AUTHOR]

Context: 1,1- and 1,2-ethenedithiol are elusive systems that could potentially exist in interstellar space, similar to analogous diols. In this paper, we investigate the structure, stability, and bonding characteristics of these compounds as well as the ions produced by protonation, deprotonation, or simple ionization processes. 1,2-ethenedithiol has two isomers, Z and E, with the most stable conformer being syn-anti for the Z isomer and anti-anti for the E isomer. However, the energy gaps between the different conformers are never larger than 6 kJ·mol−1. For 1,1-ethenedithiol, the global minimum is the syn-anti conformer. The vertical and adiabatic ionization processes as well as the intrinsic basicities and acidities of these families of compounds were analyzed and compared with those of the corresponding diols previously reported in the literature. This comparison revealed not only the numerical differences in these thermodynamic properties but also distinct trends between the two families of compounds. Methods: State-of-the-art G4 ab initio calculations were employed to calculate the structures and total energies of the systems under investigation. The QTAIM, ELF, and NBO approaches were used to analyze the electron density of all the neutral and charged systems included in our study. Van der Waals contributions, when relevant, were analyzed by locating regions of low reduced density gradient(s) using the NCIPLOT approach. [ABSTRACT FROM AUTHOR]

One of the primary and still unresolved problems of shotcreting is the high rebound rate of the material, which reaches over 20% in "dry" shotcreting. There is a practical need to improve the very principle of shotcreting and methods for optimizing the movement of torch particles. Materials and Methods: The purpose of this study was to justify the use of the electrostatic treatment of cement–sand mortar in the process of performing shotcreting works using the dry method. It was proposed that the binder and then the finished mixture be ionized step-by-step (by passing it through a non-uniform electrostatic field formed by corona electrodes). As a result, the shotcrete will be held on the fence. Results: Analysis of the modeling results shows that the presence of an electrostatic field slows down the particle and reduces the kinetic energy of the rebound. After theoretical calculations, experiments were conducted, during which, the torch size and the plant productivity were changed, and the rebound mass was weighed. After application to the surface, prototypes were formed and subjected to strength tests. It was determined that gunning in a sharply non-uniform electric field demonstrates its practical and economic efficiency due to the uniform deposition of charged particles on the treated surface and low power consumption. Conclusions: It was established that the electrostatic treatment of a cement–sand mixture during application allows concrete particles to be retained on the shotcrete surface, the rebound of the material to be reduced and the strength of concrete to be increased. [ABSTRACT FROM AUTHOR]

Cathodoluminescence of a heterostructure with CdS/ZnSe/ZnSSe quantum wells at different electron energies in the range of 3–7 keV has been studied. The dependence of the ratio of the radiation intensity of the quantum well to the intensity of radiation of the ZnSSe barrier layers matched to the GaAs substrate is obtained. This relationship is modeled for different diffusion lengths of nonequilibrium charge carriers in barrier layers and coefficients of trapping of these carriers by a quantum well. It is shown that taking the surface recombination into account gives the best modeling results. An estimate of the diffusion length of nonequilibrium carriers in barrier layers of 25 nm was obtained from comparing the simulation results and the experimental data. The effect of the diffusion length on the characteristics of a semiconductor disk laser based on heterostructures with similar quantum wells is discussed. [ABSTRACT FROM AUTHOR]

We explore a mechanism for ionization in high-velocity (but not yet relativistic) collisions of light atomic particles, one of which being initially in an excited internal state. This mechanism is driven by the generalized Breit interaction and proceeds via radiative energy transport between the colliding particles which has an extremely long range. A comparison of this mechanism with those which are 'standard' for high-velocity collisions shows that it can play a noticeable role in collisions with excited target atoms. [ABSTRACT FROM AUTHOR]

Background Development of rapid bacterial identification from blood cultures has been an area of intense study in diagnostic microbiology. Shortened turnaround time coupled with antimicrobial stewardship interventions have been shown to improve patient outcomes and decrease healthcare-associated costs. Objectives We report the validation of a short incubation method for Gram-positive and Gram-negative bacterial identification utilizing MALDI-TOF MS without additional instrumentation, processing or cost compared with current practice. Methods Prospective, observational, single-centre study in a quaternary care academic hospital encompassing 376 blood cultures subjected to bacterial identification after short incubation periods of 3–4 and 6–8 h. Results There was 97.5% species-level identification agreement with tests undertaken after 3–4 h incubation with 83.6% isolates identified, and 99.7% species-level identification agreement after 6–8 h incubation with 96.7% isolates identified. Conclusions The short incubation method provides a rapid MALDI-TOF MS bacterial identification method, reducing turnaround time by 10–18 h compared with standard practice without additional cost, processing or instrumentation. [ABSTRACT FROM AUTHOR]

The Pohang Accelerator Laboratory X‐ray Free‐Electron Laser (PAL‐XFEL) operates hard X‐ray and soft X‐ray beamlines for conducting scientific experiments providing intense ultrashort X‐ray pulses based on the self‐amplified spontaneous emission (SASE) process. The X‐ray free‐electron laser is characterized by strong pulse‐to‐pulse fluctuations resulting from the SASE process. Therefore, online photon diagnostics are very important for rigorous measurements. The concept of photo‐absorption and emission using solid materials is seldom considered in soft X‐ray beamline diagnostics. Instead, gas monitoring detectors, which utilize the photo‐ionization of noble gas, are employed for monitoring the beam intensity. To track the beam position at the soft X‐ray beamline in addition to those intensity monitors, an X‐ray ionization beam position monitor (XIBPM) has been developed and characterized at the soft X‐ray beamline of PAL‐XFEL. The XIBPM utilizes ionization of either the residual gas in an ultra‐high‐vacuum environment or injected krypton gas, along with a microchannel plate with phosphor. The XIBPM was tested separately for monitoring horizontal and vertical beam positions, confirming the feasibility of tracking relative changes in beam position both on average and down to single‐shot measurements. This paper presents the basic structure and test results of the newly developed non‐invasive XIBPM. [ABSTRACT FROM AUTHOR]

The Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL) operates hard X-ray and soft X-ray beamlines for conducting scientific experiments providing intense ultrashort X-ray pulses based on the self-amplified spontaneous emission (SASE) process. The X-ray free-electron laser is characterized by strong pulse-to-pulse fluctuations resulting from the SASE process. Therefore, online photon diagnostics are very important for rigorous measurements. The concept of photo-absorption and emission using solid materials is seldom considered in soft X-ray beamline diagnostics. Instead, gas monitoring detectors, which utilize the photo-ionization of noble gas, are employed for monitoring the beam intensity. To track the beam position at the soft X-ray beamline in addition to those intensity monitors, an X-ray ionization beam position monitor (XIBPM) has been developed and characterized at the soft X-ray beamline of PAL-XFEL. The XIBPM utilizes ionization of either the residual gas in an ultra-high-vacuum environment or injected krypton gas, along with a microchannel plate with phosphor. The XIBPM was tested separately for monitoring horizontal and vertical beam positions, confirming the feasibility of tracking relative changes in beam position both on average and down to single-shot measurements. This paper presents the basic structure and test results of the newly developed non-invasive XIBPM.

The sensitivity and accuracy of identifying volatile organic compounds using mass spectrometric gas analyzers operation in the electron ionization mode can be enhanced by increasing the number of ions formed in the ion source by varying the energy of ionizing electrons. The paper presents a comparison of data obtained by electron impact ionization at electron energy (EE) in the range of 25–105 eV for a number of organic substances belonging to different classes of organic compounds. an analysis using similarity matrices based on various similarity metrics was performed to interpret the dynamics of changes in the intensities of fragment ion peaks, and the influence of EE on the formation probability of the main fragment species of the substances under study and, accordingly, on the resemblance of a recorded mass spectrum to the reference mass spectrum from the database was shown. [ABSTRACT FROM AUTHOR]

The study of plasma generation in liquids is relevant for many applications, especially for increasing the efficiency of terahertz radiation generation. This work investigates the relationship between the laser excitation wavelength and the plasma electron density in liquid water in the near-infrared spectral range. Using numerical simulation methods based on the Keldysh theory, patterns of changes in the ionization rate and changes in the plasma electron density depending on the excitation wavelength are analyzed. The results show the mutual influence of above-threshold ionization and tunneling effects when the Keldysh parameter is close to one. A decrease in plasma electron density with increasing excitation wavelength has been shown. However, in certain wavelength ranges a local increase in plasma electron density was observed. The theoretical results obtained are consistent with the experimental data of other scientific groups. This theoretical study provides valuable information on the modulation of plasma electron density by changing laser excitation wavelengths, which is important for increasing the efficiency of terahertz radiation generation.

Using thermal nonequilibrium physicochemical kinetics models, which make it possible to numerically study the reacting gas flows with allowance for the processes of vibrational and electronic-translational relaxation and exchange, as well as the chemical and plasmachemical reactions, the profiles of the Gladstone–Dale constant and refractive index are calculated for two model problems: relaxation of the air behind the shock wave (SW) front and expansion of hydrogen and syngas combustion products in a supersonic nozzle. The required data on the electrical properties (polarizability and dipole moment) of the neutral and charged gas components in their ground and excited states are taken from the literature or estimated using recently developed analytical models. For each of the model gas-dynamic problems, the accuracy of various approximations when calculating the optical properties of a gas is analyzed. [ABSTRACT FROM AUTHOR]

The fractional step method is used to solve the ionization equations for electron-ion plasma containing neutrals in relation to processes in stationary plasma thrusters (SPT). The method uses splitting with respect to physical processes: the evolution of plasma is represented as a superposition of pure transport in an external field in phase space with subsequent ionization. The transport is calculated using the macroparticle method. The ionization process in the case of plane symmetry is calculated using explicit analytical formulas. The resulting formulas of the fractional step method are compared with the numerical solution of the plasma evolution equation using the known physical model of ionization. [ABSTRACT FROM AUTHOR]

The problem of calculating kinetic characteristics during electron drift in inert gases in a wide range of the reduced electric field strength: 0.001 Td < E/N < 10 000 Td is considered. For the case of a weak field E/N < 0.01 Td, there is little reference data, and the drift velocity, average energy, longitudinal and transverse diffusion coefficients and ionization coefficient for the cases of a weak field and a moderately strong field E/N < 100 Td were calculated using the method of dynamics of many particles involving collisions in accordance with the Monte Carlo procedure. For the cases of strong and superstrong fields 100 Td < E/N < 10 000 Td, the results of calculations for two models of electron departure from the system were considered and analyzed for the first time: (1) an avalanche model with multiplication; (2) a model with the most energetic electron in the system leaving the wall during the act of ionization or transition to the escape mode. Taking into account the appearance of new electrons in the system during ionization events under stationary current conditions made it possible to include the departure of electrons from the system to the wall with the determination of its potential into the consideration and, by analogy with the ionization coefficient, to introduce the definition of the electron runaway coefficient. For these two models, tabulated values of the electron runaway coefficient were obtained. An analysis and comparison of the calculation results with the table data was carried out. In addition, we present analytical approximations of the elastic and inelastic cross sections of electron–atom collisions depending on the collision energy that we obtained based on an analysis of the available theoretical and experimental data. They have physically reasonable asymptotics and can be recommended by us for widespread use. [ABSTRACT FROM AUTHOR]

The article presents a special stand featuring ion generators designed and manufactured for experimental research. This study investigates the use of ion energy for air purification, specifically focusing on its effect on PM (0.3–10 μm) agglomeration. By introducing charged ions into the air, particulate matter can be charged, resulting in increased particle sizes through agglomeration, and subsequently improving the filtration efficiency. Experiments were conducted in a controlled chamber to evaluate the performance of an ion-based air purification system. The effects of various parameters, such as ion concentration, airflow rate, and particle size distribution, on PM agglomeration were studied. The results demonstrated that the ion-based air purification system could effectively enhance PM agglomeration, particularly for ultrafine particles. The study also revealed that the efficiency of PM agglomeration was influenced by the ion concentration and airflow rate, with an optimal range identified to maximize the system's performance. Furthermore, the potential real-world application of this technology was discussed, considering factors such as energy consumption, maintenance requirements, and compatibility with existing air purification systems. This study contributes to the development of innovative air purification solutions and offers valuable insights into the potential of ion energy for improving indoor air quality and safeguarding human health. [ABSTRACT FROM AUTHOR]

This study investigates the impact of the ion beam on the properties of composite PEO/NiO, which was fabricated using the solution casting method and applied in advanced dielectric applications. The samples were exposed to ion beam at different fluencies (5 × 1016, 10 × 1016, and 15 × 1016 ions/cm2) using cold cathode ion source. The structure of the pure and treated PEO/NiO films was studied using the XRD technique, which demonstrated the successful fabrication of the composite PEO/NiO. Moreover, the morphological changes were analyzed by SEM, which indicates the homogeneous distribution of NiO in PEO. Furthermore, the dielectric characteristics of PEO/NiO films were tested at a frequency range of 40–106 Hz. The dielectric constant enhanced from 22.8 for PEO/NiO to 128.5 for the irradiated 15 × 1016 ions/cm2, and the energy density enhanced from 1.1x10−4 to 5.6x10−4 J/m3. The results demonstrate that the irradiated PEO/NiO composite exhibits novel dielectric properties, allowing the use of the irradiated PEO/NiO composite in different devices as super-capacitors and batteries. [ABSTRACT FROM AUTHOR]

Energetic electron precipitation (EEP) during substorms significantly affects ionospheric chemistry and lower‐ionosphere (<100 km) conductance. Two mechanisms have been proposed to explain what causes EEP: whistler‐mode wave scattering, which dominates at low latitudes (mapping to the inner magnetosphere), and magnetic field‐line curvature scattering, which dominates poleward. In this case study, we analyzed a substorm event demonstrating the dominance of curvature scattering. Using ELFIN, POES, and THEMIS observations, we show that 50–1,000 keV EEP was driven by curvature scattering, initiated by an intensification and subsequent earthward motion of the magnetotail current sheet. Using a combination of Swarm, total electron content, and ELFIN measurements, we directly show the location of EEP with energies up to ∼1 MeV, which extended from the plasmapause to the near‐Earth plasma sheet (PS). The impact of this strong substorm EEP on ionospheric ionization is also estimated and compared with precipitation of PS (<30 keV) electrons. Plain Language Summary: During magnetospheric substorms, energetic electrons in the Earth's plasma sheet (PS), the night‐side magnetosphere region filled by hot plasma, precipitate to the ionosphere. Energetic electron precipitation (EEP) affects the density, temperature, and composition of the ionosphere. However, the exact process that causes such precipitation is not well understood due to observational constraints. The challenge lies in simultaneously measuring the EEP properties at the ionosphere and the plasma and wave properties in the PS. We analyze a fortuitous satellite conjunction during a substorm, during which EEP was simultaneously captured by ELFIN, Swarm, and POES at low altitudes, and THEMIS in the equatorial PS. EEP was observed to extend across a broad equatorial domain, projecting into a wide ionospheric region and encompassing the PS region and a significant portion of the inner magnetosphere. High‐energy‐resolution measurements from ELFIN reveal that the main driver of precipitation is the scattering of energetic electrons by strongly curved magnetic field lines in the PS, as opposed to the more commonly suggested scattering mechanisms associated with wave‐particle interactions. We also show that the EEP drastically altered the ionization profile of the ionosphere. Key Points: We investigate the radial location of energetic (50–1,000 keV) electron precipitation (EEP) during a substormWe compare the impact of plasma sheet electron precipitation (<30 keV) and EEP (50–1,000 keV) on the altitudinal profile of ionizationOur results underscore the key role of curvature scattering in energetic electron precipitation during substorms [ABSTRACT FROM AUTHOR]

In high-energy physics, one of the key areas of research is the study of extensive air showers (EAS). This phenomenon remains insufficiently understood; scientists still lack comprehensive knowledge about the nature of their origin and the mechanisms responsible for their formation in the upper layers of the atmosphere. In this paper, the main characteristics and properties of air showers are described in detail. Numerous experiments conducted at the Hadron-55 complex form the foundation of EAS research. The showers were recorded and analyzed using the ionization calorimeter method, which measures the energy of EAS by detecting the total ionization produced by particles. This calorimeter, equipped with iron and lead absorbers, ensures high measurement accuracy, with an experimental error of only 10%. The experimental data were processed using a program developed in C++. The experiments revealed that the most common particles in the showers are electron-photon and hadronic components, which account for 95-98% of the particles in the shower core. A total of 8717 showers were processed by the program over a period of 485 hours. An analysis of the energy range of the registered showers supports the theory of their galactic origin. Additionally, calculating the primary parameters allows for further, more detailed studies of EAS. [ABSTRACT FROM AUTHOR]

The paper presents the results of a theoretical study of the electron- impact ionization of the 6p, 6s, and 5d shells of the Pb and Bi atoms. Calculations are performed using three relativistic approximations, namely distorted waves, Coulomb-Born, and binary-encounter-dipole, in a wide range of collision energies from thresholds to 700 eV. The ionization cross sections of the sub valent 5d shell of the Pb and Bi atoms are calculated for the first time. It is established that this shell contributes to the total direct ionization cross section twice as much as the 6s shell (up to 26% for Pb and up to 38% for Bi), which shows the importance of taking this process into account in modeling different types of plasma. We analyzed the behavior of the partial ionization cross sections of these atoms calculated using various approximations. Comparison of the resultant full direct ionization cross sections with the data of other authors shows that they satisfactorily describe the process of direct ionization. However, for a more detailed analysis and comparison with experimental data additional calculations of the main process of indirect ionization, namely excitation of autoionization, for the Pb and Bi atoms are required. Analysis of the influence of the third valence electron of the Bi atom compared to the Pb atom on the core-valence interaction shows that this influence is the most significant in the case of the distorted waves approximation. The difference in the behavior of the direct ionization cross sections is caused, in our opinion, by the interaction of valence electrons among themselves. [ABSTRACT FROM AUTHOR]

Procedures of the Direct Simulation Monte Carlo method for weakly ionized flows around reentry vehicles are presented. For ionization and recombination reactions, expressions for the model dependence of the reaction probability on velocities and energies of reagents are derived. An algorithm of dissociative recombination is presented, whose computational efficiency is reached by bypassing the modeling of the interaction of electrons and heavy particles. An approach to the construction of a weighting scheme for elastic collisions and chemical reactions is described, which significantly increases the computational efficiency of the algorithm. An example of using these numerical models and procedures for studying a weakly ionized flow around a reentry capsule under typical reentry co-nditions is given. The computation results are compared to plasma parameters measured in flight experiments. [ABSTRACT FROM AUTHOR]

The single-center convergent close-coupling (CCC) method is applied to calculate positron scattering from boron. A model potential approach is utilized to extract the positronium formation, direct ionization, and values between the positronium formation and ionization thresholds. We present results for total, electron loss, elastic, momentum transfer, total bound state excitation, positronium formation, direct ionization, stopping power, and mean excitation energy from 10 − 5 eV to 5000 eV. For boron, there is only one other set of theoretical positron calculations for elastic and momentum transfer above 500 eV, which is in excellent agreement with the current CCC results. Using the current results for boron atoms and previous CCC calculations for hydrogen and fluorine atoms, positron scattering from BF, BF 2 , BF 3 , and BH molecules is calculated for energies between 0.1 eV and 5000 eV with a modified independent atom approach. [ABSTRACT FROM AUTHOR]

Background: Particle accelerators, manufactured for delivering patient radiation treatment, require numerous and frequent quality assurance measures. One of those is the periodic check for electron energy stability. The American Association of Physicists in Medicine has established requirements for this procedure. The current recommendation is to perform a ratio of two ionization points, one at Dmax and another at a point approximately to the 50% depth, compared to a baseline as a relative check. Purpose: This ratio method is a sensitive measurement and sometimes produces results that are difficult to interpret or relate to acceptable tolerances. We sought to find a simple method that gives more stable results, which can be interpreted and related to energy changes. Method: We propose a method that takes two measurements on the descending portion of the shifted percent depth ionization (PDI) curves to calculate the slope, tangent to the I50 point, the point at which the ionization falls to 50% of its maximum value. We then used the slope measurement, compared to an established baseline, to relate energy. Results: After collecting data over a 3‐year period, we saw that standard deviations for the slope method have much less variability than the traditional ratio method. We were also able to correlate the slope results to ionization scans performed in water and found they were in better agreement than the traditional ratio method. Conclusion: The slope method does not require precise positioning since the slope remains relatively constant over the descending portion of the curve. Our data show that this results in an easier interpretative test of electron energy stability and delivers reliable feedback for quality assurance. [ABSTRACT FROM AUTHOR]

This study delves into the transformative effects of atmospheric cold plasma (CP) treatment on little millet flour (LMF), specifically exploring alterations in bioactive compounds, antinutritional factors, and functional properties. Foaming and emulsification properties experienced noteworthy enhancements with plasma treatment, manifesting in significant increases in foaming capacity (up to 51.47 ± 0.49%), foaming stability, emulsification ability, and emulsion stability (up to 47.02 ± 0.35%). The treatment also positively influenced water absorption index and swelling power. Antinutritional factors, including tannins and saponins, exhibited substantial reductions following plasma treatment. Saponin content, for instance, decreased by an impressive 58% after exposure to 20 kV for 20 min. Conversely, bioactive compounds such as phenolic content and antioxidant activity saw significant increases. Total phenolic content (TPC) rose from 527.54 ± 8.94 to 575.82 ± 3.58 mg GAE/100 g, accompanied by a remarkable 59% boost in antioxidant activity. Interestingly, plasma treatment did not exhibit a discernible effect on pasting properties. These findings collectively underscore the potential of atmospheric CP treatment as a novel and effective method for enhancing the functional and nutritional attributes of LMF, thereby opening new avenues for its application in food science and technology. [ABSTRACT FROM AUTHOR]

In this study, we present a complete set of electron scattering cross-sections from 1-Methyl-5-Nitroimidazole (1M5NI) molecules for impact energies ranging from 0.1 to 1000 eV. This information is relevant to evaluate the potential role of 1M5NI as a molecular radiosensitizers. The total electron scattering cross-sections (TCS) that we previously measured with a magnetically confined electron transmission apparatus were considered as the reference values for the present analysis. Elastic scattering cross-sections were calculated by means of two different schemes: The Schwinger multichannel (SMC) method for the lower energies (below 15 eV) and the independent atom model-based screening-corrected additivity rule with interferences (IAM-SCARI) for higher energies (above 15 eV). The latter was also applied to calculate the total ionization cross-sections, which were complemented with experimental values of the induced cationic fragmentation by electron impact. Double differential ionization cross-sections were measured with a reaction microscope multi-particle coincidence spectrometer. Using a momentum imaging spectrometer, direct measurements of the anion fragment yields and kinetic energies by the dissociative electron attachment are also presented. Cross-sections for the other inelastic channels were derived with a self-consistent procedure by sampling their values at a given energy to ensure that the sum of the cross-sections of all the scattering processes available at that energy coincides with the corresponding TCS. This cross-section data set is ready to be used for modelling electron-induced radiation damage at the molecular level to biologically relevant media containing 1M5NI as a potential radiosensitizer. Nonetheless, a proper evaluation of its radiosensitizing effects would require further radiobiological experiments.

In this article, the diffusion Monte Carlo (DMC) method is applied to the study of the quantum states of a hydrogen atom confined into a cylindrical potential well. We present an independent reproduction of previous studies based on different methods, in particular the energy eigenvalues for ground and selected excited states and the polarizability of the ground state, both for finite and infinite cylinders. The static field ionization of ground and excited states of the confined atom is discussed, including the determination of the potential energy surface and equilibrium position of the proton. This study provides a further demonstration of the versatility of the DMC method for this and analogous problems. [ABSTRACT FROM AUTHOR]

Time‐resolved photoelectron spectroscopy is a powerful pump‐probe technique which can probe nonadiabatic dynamics in molecules. Interpretation of the experimental signals however requires input from theoretical simulations. Advances in electronic structure theory, nonadiabatic dynamics, and theory to calculate the ionization yields, have enabled accurate simulation of time‐resolved photoelectron spectra leading to successful applications of the technique. We review the basic theory and steps involved in calculating time‐resolved photoelectron spectra, and highlight successful applications. This article is categorized under:Electronic Structure Theory > Ab Initio Electronic Structure MethodsTheoretical and Physical Chemistry > Spectroscopy [ABSTRACT FROM AUTHOR]

The electronic structure and ionization spectrum of 6,6-dimethylfulvene were calculated using the third-order algebraic-diagrammatic construction method for the one-particle Green's function (IP-ADC(3)) and the equation-of-motion coupled-cluster method at the level of singles and doubles model (IP-EOM-CCSD). The results were used to interpret the recently obtained photoelectron spectrum of 6,6-dimethylfulvene (M.H. Palmer et al., Chem. Phys. Lett. 796, 139558 (2022)). A number of new assignments have been proposed, among which the most significant is the assignment of the previously unassigned shoulder of the third photoelectron band at 10.5 eV, which, according to our IP-ADC(3)-calculations, is formed by the satellite transitions associated with the 2a2 and 2b1 π-orbitals of the fulvene ring. The data obtained in this study also suggest that using the IP-EOM-CCSD method and equivalent approaches involves difficulties with correct description of the satellite states. [ABSTRACT FROM AUTHOR]

The electrical properties of Pd/InP Schottky diodes and Pd-layers deposited on glass substrate by thermal evaporation in vacuum, and placed in hydrogen medium containing 10–100 vol % of hydrogen, were studied. The current generation in Pd/InP Schottky diodes, as well as the decrease in resistance of Pd layers were observed in hydrogen medium. It is proposed that the current generation in the structures under study is due to free electrons as result of hydrogen atoms ionization. The current induced by these electrons exists in electric circuit until hydrogen is present in the environment. It is shown that the hydrogen current generators can be created based on the Pd/InP diode structure. [ABSTRACT FROM AUTHOR]

Four-body formalism of the three-Coulomb wave (3CW-4B) model has been employed to investigate the simultaneous ionization and excitation of He by the impact of fast electron and positron. In this method, the incident wave is described by a plane wave, and the final state wavefunction is a product of the three-Coulomb wave due to the correlated motion of the three unbound charged particles. The triple differential cross sections (TDCS) are calculated and analysed for both the asymmetric coplanar and perpendicular geometries for the incident energies of 0.57, 1.5, and 5.5 keV at several electron emission energies. The distinguishing features have been noted in the angular distribution of the ejected electron. A significant difference in the TDCS structure, especially in the region of binary and recoil peak is found by choosing two different forms of bound state wave function of He in its ground state. The results of the 3CW-4B model are compared to the available experimental and theoretical findings. We find a very good agreement between the present result and the experimental data for pure single ionization, whereas some disagreement has been found in the process of simultaneous ionization with excitation to the n=2 state of H e + . Finally, by changing the sign of the projectile’s charge, significant differences have been observed between the two sets of results for electron and positron impact. [ABSTRACT FROM AUTHOR]

Objectives Matrix-assisted laser desorption ionization time of flight (MALDI-TOF) has revolutionized clinical microbiology laboratories, enabling the identification of microorganisms in minutes. Although this advancement has significantly enhanced patient care by providing early diagnosis, the use of MALDI-TOF for routine detection of antimicrobial resistance (AMR) remains an ongoing area of research. The purpose of this scoping review was to identify and summarize the existing literature on MALDI-TOF–based methodologies for detecting AMR. Methods The PubMed, Embase, and Cumulative Index to Nursing and Allied Health Literature databases were searched for articles published up to July 2023. Publications were carefully screened, and inclusion was based on their relevance to the topic and detailed explanations of the methodologies employed. Results We reviewed 49 articles and identified various MALDI-TOF–based approaches for detecting AMR that we grouped in 2 main categories: (1) bacterial growth detection following a brief incubation with antibiotics and (2) identification of specific mass spectral profiles associated with drug resistance. Recently, the use of machine learning algorithms has been explored to detect characteristic patterns associated with AMR. Thorough evaluation of each study's procedures was conducted to determine their potential for implementation in clinical laboratories. Conclusions MALDI-TOF shows promise as a tool for AMR detection, but its readiness for wider clinical adoption relies on ongoing research, development of algorithms and software for automated interpretation of mass spectra, and validation efforts. Its role in routine clinical practice may evolve as technology and knowledge progress. [ABSTRACT FROM AUTHOR]

We report an ultrafast oscillation (up to ∼ 10 4 GHz) in the early stage of field emission-driven microdischarges. Spatiotemporal behaviors of electron density, space charge density, and electric field, exhibiting high-frequency oscillations, are demonstrated based on first-principle particle-in-cell/Monte Carlo collision simulations. Intermittent electron emission fluxes are identified from the electron phase space distributions whereas the ions are rather non-oscillatory in the transient timescale. The mechanisms of oscillation with growing amplitude are found to be related to the rapid modification of the field emission current affected by the space charge electric field, which is also accompanied by the fast response of the electron transport and ionization in a dynamic double-layer sheath. Further, a transport equation for emission current is solved to estimate the oscillation frequency, which agrees well with the simulation results. This study provides a more precise understanding of the formation of the field emission-driven microdischarge, which informs the design and optimization of miniaturized gaseous electronic devices. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We present ionization cross sections of hydrogen molecules by electron and positron impact for impact energies between 20 and 1000 eV. A three-body Classical Trajectory Monte Carlo approximation is applied to mimic the collision system. In this approach, the H2 molecule is modeled by a hydrogen-type atom with one active electron bound to a central core of effective charge with an effective binding energy. Although this model is crude for describing a hydrogen molecule, we found that the total cross sections for positron impact agree reasonably well with the experimental data. For the electron impact, our calculated cross sections are in good agreement with the experimental data in impact energies between 80 eV and 400 eV but are smaller at higher impact energies and larger at lower impact energies. Our calculated cross sections are compared with the scaled cross sections obtained experimentally for an atomic hydrogen target. We also present single differential cross sections as a function of the energy and angle of the ejected electron and scattered projectiles for a 250 eV impact. These are shown to agree well with available data. Impact parameter distributions are also compared for several impact energies. [ABSTRACT FROM AUTHOR]

The ionization of a rarefied gas in a short gap by a stream of short-wave radiation and fast electrons from the plasma of an auxiliary spark discharge along the dielectric surface is detected, sufficient to initiate an arc discharge in the gap. The density of the ionizing flow of particles and radiation determines the delay time of the switching gap in relation to the start of the auxiliary discharge. With an increase in the initial concentration of free electrons in the main discharge gap, the transition time to an arc discharge is reduced, due to the development of instabilities. [ABSTRACT FROM AUTHOR]

In this work, a system of kinetic equations is constructed to study the processes in a three-component plasma. It is an analogue of the Krook model, which is widely used in the dynamics of rarefied gases. The model is supposed to be used to study the processes in the channels of rocket electric thrusters. [ABSTRACT FROM AUTHOR]

Jet fuels are complex mixtures composed of many individual compounds that influence crucial chemical and physical properties. Approximately over the last 20 years, mass spectrometry studies provided important and extensive qualitative and quantitative information of the compounds that make up jet fuels. This review presents these main findings, evaluates the analytical methods utilized, and summarizes the hydrocarbons, nitrogen‐, oxygen‐ and sulfur‐containing compounds characterized in the jet fuels. Potential areas where mass spectrometry may play important roles in the future will also be discussed. [ABSTRACT FROM AUTHOR]

Compression ignition engines will continue to power heavy-duty, long-haul vehicles, and heavy machinery in the future, while batteries become more prevalent in powering light-duty vehicles. However, compression ignition engines face problems when started under severe cold conditions. These problems include combustion instability, misfiring, and higher emissions of unburnt hydrocarbons. Feedback of an engine's performance to its control unit can be used to improve the fuel injection strategy in real time and mitigate these problems. The ion current signal, being reflective of the combustion and emissions characteristics, has already been proven as a reliable feedback signal under warmed-up conditions. This paper investigates the ion current signal as potential feedback during the cold starting and the warm-up period. Cold starting experiments were conducted in a VW's 2.0-L, direct injection, four-cylinder compression ignition engine at ambient temperatures of −10°C, 0°C, 10°C, and 20°C. The engine experienced misfiring cycles at the ambient temperatures of −10°C and 0°C. In some misfiring cycles, the ion current was detected even though the pressure trace did not show a distinct combustion event, indicating that the autoignition occurred but the combustion failed to sustain. This means the ion current can identify un-sustained combustion events in misfiring cycles. In firing cycles, an ion current characteristic could well predict the combustion phasing at ambient temperatures of 10°C and 20°C. The real-time feedback of (1) un-sustained combustion events in misfiring cycles and (2) combustion phasing in firing cycles at various ambient temperatures can be utilized to mitigate cold starting problems in compression ignition engines. [ABSTRACT FROM AUTHOR]

Background and Purpose. The classical drug discovery toolbox continually expands beyond traditional rule of five (Ro5)-compliant small molecules to include new chemical modalities for difficult-to-drug targets. The paper focuses on the molecular properties essential to drive oral bioavailability within the bRo5 framework. Experimental Approach. The first part outlines the concept and methodologies for characterizing bRo5 physicochemical properties, including considerations on chameleonicity; in particular, the paper sum­marizes the content of the last author’s talk presented during the IAPC-10 Meeting held in Belgrade in September 2023 (https://iapchem.org/index.php/iapc-10-home). The second part of the manuscript presents novel experimental and computational data on three proteolysis targeting chimeras (PROTACs) currently in clinical trials. Key Results. Molecular descriptors of ARV-110, ARV-471, and DT-2216 are reported and the main limitations of the applied experimental approaches are discussed. Moreover, a simple computational method shows how predicting the presence of chameleonic effects. Conclusion. A full complete physicochemical characterization of three degraders in clinical trial is reported to highlight the differences in physicochemical descriptors between PROTACs dosed orally and intravenously.

Abstract Energetic electron precipitation (EEP) during substorms significantly affects ionospheric chemistry and lower‐ionosphere (

The purpose of this review and commentary was to provide an historical and evidence-based account of organic acids and the biochemical and organic chemistry evidence for why cells do not produce metabolites that are acids. The scientific study of acids has a long history dating to the 16th and 17th centuries, and the definition of an acid was proposed in 1884 as a molecule that when in an aqueous solution releases a hydrogen ion (H+). There are three common ionizable functional groups for molecules classified as acids: 1) the carboxyl group, 2) the phosphoryl group and 3) the amine group. The propensity by which a cation will associate or dissociate with a negatively charged atom is quantified by the equilibrium constant (Keq) of the dissociation constant (Kd) of the ionization (Keq ​= ​Kd), which for lactic acid (HLa) vs. lactate (La-) is expressed as: Keq=Kd=[H+][La−][HLa]= 4 677.351 4 (ionic strength ​= ​0.01 Mol⋅L-1, T ​= ​25 ​°C). The negative log10 of the dissociation pKd reveals the pH at which half of the molecules are ionized, which for HLa ​= ​3.67. Thus, knowing the pKd and the pH of the solution at question will reveal the extent of the ionization vs. acidification of molecules that are classified as acids.

One of the primary and still unresolved problems of shotcreting is the high rebound rate of the material, which reaches over 20% in “dry” shotcreting. There is a practical need to improve the very principle of shotcreting and methods for optimizing the movement of torch particles. Materials and Methods: The purpose of this study was to justify the use of the electrostatic treatment of cement–sand mortar in the process of performing shotcreting works using the dry method. It was proposed that the binder and then the finished mixture be ionized step-by-step (by passing it through a non-uniform electrostatic field formed by corona electrodes). As a result, the shotcrete will be held on the fence. Results: Analysis of the modeling results shows that the presence of an electrostatic field slows down the particle and reduces the kinetic energy of the rebound. After theoretical calculations, experiments were conducted, during which, the torch size and the plant productivity were changed, and the rebound mass was weighed. After application to the surface, prototypes were formed and subjected to strength tests. It was determined that gunning in a sharply non-uniform electric field demonstrates its practical and economic efficiency due to the uniform deposition of charged particles on the treated surface and low power consumption. Conclusions: It was established that the electrostatic treatment of a cement–sand mixture during application allows concrete particles to be retained on the shotcrete surface, the rebound of the material to be reduced and the strength of concrete to be increased.