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The paper presents the results of studies of argon-nitrogen plasma of a non-self-sustained low-pressure glow discharge with a hollow cathode by optical emission spectrometry. The plasma was generated in a mixture of Ar–N2 gases with an argon percentage from 0 to 100% at a total pressure of 1 Pa. The discharge current and voltage were maintained constant and amounted to 18 A and 165 V, respectively. A significant increase in the amount of Ar+ (up to 30%) at a nitrogen content of 10–25% was shown, which is associated with a shift in the reaction of charge exchange of nitrogen with argon towards the generation of argon ions. It was found that at a low partial pressure of nitrogen (≈10%), a sharp increase in the content of atomic nitrogen is observed which is probably due to the dissociation of nitrogen molecules upon collisions with an excited argon atom. [ABSTRACT FROM AUTHOR]

Single hot-wire velocity measurements have been conducted along a three-dimensional measurement grid to capture the flow-field induced by a 45 ∘ inclined slotted pulsed jet. Based on the periodic behavior of the flow, two different estimation methods have been implemented. The first one, considered as the reference baseline, is the conditional approach which consists in the redistribution of the experimental data into space- and time-resolved three-dimensional velocity fields. The second one uses a neural network to estimate 3D velocity fields given spatial coordinates and time. This paper compares the two methods for a complete flow-field estimation based on hot-wire measurements. Results suggest that the neural network is tailored to capture the phase-averaged dynamic response of the jet induced by the actuator, and identify the coherent structures in the flow field. Interesting performances are also observed when degrading the learning database, meaning that neural networks can be used to drastically improve the temporal or spatial resolution of a flow field estimation compared to the experimental data resolution. [ABSTRACT FROM AUTHOR]

The NUMEN (NUclear Matrix Elements for Neutrinoless double beta decay) project was recently proposed with the aim to investigate the nuclear response to Double Charge Exchange reactions for all the isotopes explored by present and future studies of 0νββ decay. The expected level of radiation in the NUMEN experiment imposes severe limitations on the average lifetime of the electronic devices. During the experiments, it is expected that the electronic devices will be exposed to about 105 neutrons/cm2/s according to FLUKA simulations. This paper investigates the reliability of a System On Module (SOM) under neutron radiation. The tests were performed using thermal, epithermal, and fast neutrons produced by the Instituto de Pesquisas Energéticas e Nucleares 4.5 MW Nuclear Research Reactor. The results show that the National Instruments SOM is robust to neutron radiation for the proposed applications in the NUMEN project. [ABSTRACT FROM AUTHOR]

In this paper, two kinds of hybrid α-Fe2O3@Co3O4 and α-Fe2O3@MnCo2O4 composites with high yield have been successfully synthesized on a flexible carbon cloth via simple solution methods. These as-obtained products serve as supercapacitor electrodes without the use of any adscititious surfactants and binders. These two hybrid electrode architectures make full use of the synergistic effects between α-Fe2O3 frameworks and coated Co3O4 or MnCo2O4 layers. They exhibit obviously enhanced discharge areal capacitance of 490 mF cm−2 and 1073 mF cm−2 for α-Fe2O3@Co3O4 and α-Fe2O3@MnCo2O4 composites at 1 mA cm−2 with an identical potential voltage of 0–0.9 V. Long-life cycling stability with capacitance retention of 74.6% for α-Fe2O3@Co3O4 and 77.8% for α-Fe2O3@MnCo2O4 are presented after 6000 charge/discharge cycles, respectively. Such prominent electrochemical performances are mainly ascribed to the hybrid composites, which can provide a large reaction surface area, fast ion and electron transfer and good structure combination stability. The as-synthesized flexible hybrid composites might have promising applications in micro/nanoscale energy storage devices. [ABSTRACT FROM AUTHOR]

In this paper, the preparation of some isotopically selected targets by ion implantation is described. The selected isotopes to be implanted over graphite matrices described in the present work were 127I and 81Br. These isotopes were chosen for their similarity with the xenon and krypton isotopes of interest for the study of Double Charge Exchange reactions in the NUMEN project (Nuclear Matrix Elements for the Neutrino-less double beta decay). The characterization of the resulting targets after implantation was carried out using Rutherford Back Scattering Spectroscopy (RBS) with 1H, 12C, 28Si beams at different energies and scattering angles. [ABSTRACT FROM AUTHOR]

Abstract: Various doped materials have been investigated to improve the structural stability of layered transition metal oxides for lithium‐ion batteries. Most doped materials are obtained through solid state methods, in which the doping of cations is not strictly site selective. This paper demonstrates, for the first time, an in situ electrochemical site‐selective doping process that selectively substitutes Li+ at Li sites in Mn‐rich layered oxides with Mg2+. Mg2+ cations are electrochemically intercalated into Li sites in delithiated Mn‐rich layered oxides, resulting in the formation of [Li1−xMgy][Mn1−zMz]O2 (M = Co and Ni). This Mg2+ intercalation is irreversible, leading to the favorable doping of Mg2+ at the Li sites. More interestingly, the amount of intercalated Mg2+ dopants increases with the increasing amount of Mn in Li1−x[Mn1−zMz]O2, which is attributed to the fact that the Mn‐to‐O electron transfer enhances the attractive interaction between Mg2+ dopants and electronegative Oδ− atoms. Moreover, Mg2+ at the Li sites in layered oxides suppresses cation mixing during cycling, resulting in markedly improved capacity retention over 200 cycles. The first‐principle calculations further clarify the role of Mg2+ in reduced cation mixing during cycling. The new concept of in situ electrochemical doping provides a new avenue for the development of various selectively doped materials. [ABSTRACT FROM AUTHOR]

Cobalt and Fe were co-electrodeposited as single crystal, faceted particles onto carbon paper to produce Co/Fe-oxyhydroxide oxygen evolution reaction (OER) catalysts with various Co/Fe ratios. Electron microscopy and Auger electron spectroscopy were used to investigate the morphology and composition of the electrodeposits. Iron content in the deposits increased with increasing Fe concentration in the electrolyte and Fe segregated to the particle surfaces. Electrochemical tests demonstrated that the deposit Co/Fe ratio influences OER activity by altering the electrochemically active surface area (ECSA) and charge transfer resistance. The OER activity increased with increasing Fe content up to ∼65 at% Fe, with a minimum overpotential of 0.33 V at 10 mA cm −2 in 1 M KOH. The fabricated OER catalysts were assembled into a Zn-air battery for discharge-charge cycling tests and showed lower charge potentials compared with bare carbon paper. [ABSTRACT FROM AUTHOR]

The theory of heavy ion double charge exchange (DCE) reactions proceeding by effective rank-2 isotensor interactions is presented. Virtual pion–nucleon charge exchange interactions are investigated as the source for induced isotensor interactions, giving rise to the Majorana DCE (MDCE) reaction mechanism. MDCE is of a generic character, proceeding through pairs of complementary ( π ± , π ∓ ) reactions in the projectile and target nucleus. The dynamics of the elementary processes is discussed, where the excitation of pion–nucleon resonances are of central importance. Investigations of initial and final state ion–ion interactions show that these effects are acting as vertex renormalizations. In closure approximation, well justified by the finite pion mass, the second-order transition matrix elements reduce to pion potentials and effective two-body isotensor DCE interactions, giving rise also to two-body correlations in either of the participating nuclei. Connections to neutrinoless Majorana double beta decay (MDBD) are elucidated at various levels of the dynamics, from the underlying fundamental electro-weak and QCD scales to the physical scales of nuclear MDBD and MDCE physics. It is pointed out that heavy ion MDCE reactions may also proceed by competing electro-weak charge exchange processes, leading to lepton MDCE by electrons, positrons, and neutrinos. [ABSTRACT FROM AUTHOR]

B replying to b Shaun G. Ard et al. I Nature Communications i https://doi.org/10.1038/s41467-022-30566-3 (2022) In our 2020 Nature Communications paper[1], we reported a strong inverse kinetic isotope effect in the charge transfer reactions of NH SB 3 sb and ND SB 3 sb with Xe SP + sp ( SP 2 sp P SB 3/2 sb ) ions. 10.1039/D1SC01652K 3 Ard, S, Viggiano, A. A, Sweeny, B. C, Long, B. & Shuman, N. Inconsistent kinetic isotope effect in ammonia charge exchange reaction measured in a Coulomb crystal and in a selected-ion flow tube. For example, there is no sympathetic cooling of rotational or vibrational modes of trapped ions as the interaction range is too long (neighbouring ions are separated by 10-20 m); the reaction complex therefore will not undergo any inelastic collisions with other co-trapped ions. [Extracted from the article]

Iron is an essential element for almost all organisms on Earth. It is necessary for a number of crucial processes such as hemoglobin and myoglobin transport and storage of oxygen in mammals; electron transfer support in a variety of iron-sulfur protein or cytochrome reactions; and activation and catalysis of reactions of a wide range of substrate like alkanes, olefins, and alcohols. Living organisms adopted iron as the main metal to carry out all of these functions due to the rich coordination chemistry of its two main redox states, Fe2+ and Fe3+, and because of its abundance in the Earth's crust and oceans. This paper presents an overview of the coordination chemistry of iron that makes it suitable for a large variety of functions within biological systems. Despite iron's chemical advantages, organisms were forced to manage with some drawbacks: Fe3+ insolubility and the formation of toxic radicals, especially the hydroxyl radical. Iron chemistry within biology is an example of how organisms evolved by creating molecular machinery to overcome these difficulties and perform crucial processes with extraordinary elegance and efficiency. © 2017 IUBMB Life, 69(6):382-388, 2017 [ABSTRACT FROM AUTHOR]

When coupled with transient absorption spectroscopy, pulse radiolysis, which utilizes high-energy electron pulses from an accelerator, is a powerful tool for investigating the kinetics and thermodynamics of a wide range of radiation-induced redox and electron transfer processes. The majority of these investigations detect transient species in the UV, visible, or near-IR spectral regions. Unfortunately, the often-broad and featureless absorption bands in these regions can make the definitive identification of intermediates difficult. Time-resolved vibrational spectroscopy would offer much improved structural characterization, but has received only limited application in pulse radiolysis. In this paper, we describe in detail the development of a unique nanosecond time-resolved infrared (TRIR) detection capability for condensed-phase pulse radiolysis on a new beam line at the LEAF facility of Brookhaven National Laboratory. The system makes use of a suite of high-power, continuous wave external-cavity quantum cascade lasers as the IR probe source, with coverage from 2330 to 1051 cm-1. The response time of the TRIR detection setup is ~40 ns, with a typical sensitivity of ~100 µOD after 4-8 signal averages using a dual-beam probe/reference normalization detection scheme. This new detection method has enabled mechanistic investigations of a range of radiation-induced chemical processes, some of which are highlighted here. [ABSTRACT FROM AUTHOR]

The interaction between neutrals outside tokamak plasmas and fast ions that are generated by neutral beam injection and pass outside the plasma is studied. It is shown that at beam energies up to ~100 keV fast-ion losses are significant, up to 20% in the studied case, because of charge exchange reactions between the neutrals and the fast ions. About half of the fast ions that neutralize outside the plasma get lost to the wall while the other half re-enters the plasma and ionizes again, often on better confined orbits, which is visible as an enhanced beam power deposition in the plasma core (). As a result, the plasma performance as measured from beam-plasma fusion reactions is hardly changed despite the significant fast-ion losses toward the plasma edge. [ABSTRACT FROM AUTHOR]

Physics cases of increasing interest in the recent years, such as the study of double charge exchange reactions for neutrino physics, require the study of very suppressed reaction channels in medium-heavy ion induced nuclear reactions. The main experimental challenges are the possibility to identify and detect the medium-heavy quasi-projectiles and the capability to measure very low cross-sections (few nb) with high sensitivity at very forward angles, including zero degree. The experimental techniques adopted in the setup of the MAGNEX magnetic spectrometer to face these issues are described in this paper. [ABSTRACT FROM AUTHOR]

The charge exchange (CE) reaction is an effective probe to study the structure of atomic nuclei in the isospin dimension, which has been studied for decades. To expand the range of nuclei studied by CE reactions to a wider range and research the structure characteristics of unstable nuclei, including the isospin symmetry, spin-isospin excitation, and nuclear symmetry energy, a semi-cylindrical time projection chamber (scTPC) prototype was designed and constructed to probe ( 3 He,t) CE reactions in inverse kinematics. The 266 nm UV laser was used to achieve electron-drift-velocity calibration. The scTPC has an energy resolution (FWHM) of 5.6% for α particles emitted by 241 Am radioactive source. The position resolution of scTPC is described by the residual method. The spatial resolution on the pad plane is 409 μ m. And the position resolution in the drift direction is 326 μ m, equivalent to an angular resolution of 0.4 ∘ . These performances suggest that the scTPC can measure Δ E and particle tracks precisely. The successful development of the scTPC prototype provides better conditions for the next step of experimental data analysis and processing. [ABSTRACT FROM AUTHOR]

This paper analyzes the slow-varying electric fields and the associated currents of a total of 35 negative upward lightning initiated by the Peissenberg tower, Germany. Thirty-four of which were from winter upward lightning and only one from summer upward lightning. It appears that all of the winter upward lightning were initiated without nearby preceding lightning activity (called “self-initiated” lightning) and only the summer lightning was triggered by nearby lightning activity (called “other-triggered” lightning). The slow-varying electric fields of the winter upward lightning showed a fast rise characterized by the 10–90% risetime, with an arithmetic mean of 13.8 ms. After attaining the maximum, the electric field turned into a slow decay being characterized by the time on half value which was evaluated to having the arithmetic mean of 441 ms. Transported charges to ground were on average 44.8 C and on maximum 165 C. The maximum value of the electric field was 39.9 kV/m on average, with the highest value being 64.5 kV/m. For the electric fields, higher values were prevented by recovery effects such as the corona from objects at ground and the redistribution of the charge in the thundercloud. Due to these effects, no or only weak correlations were found between the 10–90% risetime, the time on half value, the charge, and the maximum of the electric field. From additional measurements with a field mill, it was found that the electric field recovers to the starting level within some seconds. [ABSTRACT FROM PUBLISHER]

Astatine isotopes can be produced in liquid lead-bismuth eutectic targets through proton-induced double charge exchange reactions on bismuth or in secondary helium-induced interactions. Models implemented into the most common high-energy transport codes generally have difficulties to correctly estimate their production yields as was shown recently by the ISOLDE Collaboration, which measured release rates from a lead-bismuth target irradiated by 1.4 and 1 GeV protons. In this paper, we first study the capability of the new version of the Liège intranuclear cascade model, INCL4.6, coupled to the deexcitation code ABLA07 to predict the different elementary reactions involved in the production of such isotopes through a detailed comparison of the model with the available experimental data from the literature. Although a few remaining deficiencies are identified, very satisfactory results are found, thanks in particular to improvements brought recently on the treatment of low-energy helium-induced reactions. The implementation of the models into MCNPX allows identifying the respective contributions of the different possible reaction channels in the ISOLDE case. Finally, the full simulation of the ISOLDE experiment is performed, taking into account the likely rather long diffusion time from the target, and compared with the measured diffusion rates for the different astatine isotopes, at the two studied energies, 1.4 and 1 GeV. The shape of the isotopic distribution is perfectly reproduced as well as the absolute release rates, assuming in the calculation a diffusion time between 5 and 10hours. This work finally shows that our model, thanks to the attention paid to the emission of high-energy clusters and to low-energy cluster induced reactions, can be safely used within MCNPX to predict isotopes with a charge larger than that of the target by two units in spallation targets, and, probably, more generally to isotopes created in secondary reactions induced by composite particles. [ABSTRACT FROM AUTHOR]

Background: Electron-capture reaction rates on medium-heavy nuclei are an important ingredient for modeling the late evolution of stars that become core-collapse or thermonuclear supernovae. The estimation of these rates requires the knowledge of Gamow-Teller strength distributions in the β+ direction. Astrophysical models rely on electron-capture rate tables largely based on theoretical models, which must be validated and tested against experimental results. Purpose: This paper presents a systematic evaluation of the ability of theoretical models to reproduce experimental Gamow-Teller transition strength distributions measured via (n,p)-type charge-exchange reactions at intermediate beam energies. The focus is on transitions from stable nuclei in the pf shell (45 ≤ A ≤ 64). In addition, the impact of deviations between experimental and theoretical Gamow-Teller strength distributions on derived stellar electron-capture rates is investigated. Method: Data on Gamow-Teller transitions from 13 nuclei in the pf shell measured via charge-exchange reactions and supplemented with results from β-decay experiments where available, were compiled and compared with strength distributions calculated in shell models (using the GXPF1a and KB3G effective interactions) and quasiparticle random-phase approximation (QRPA) using ground-state deformation parameters and masses from the finite-range droplet model. Electron-capture rates at relevant stellar temperatures and densities were derived for all distributions and compared. Results: With few exceptions, shell-model calculations in the pf model space with the KB3G and GXPF1a interactions qualitatively reproduce experimental Gamow-Teller strength distributions of 13 stable isotopes with 45 ≤ A ≤ 64. Results from QRPA calculations exhibit much larger deviations from the data and overestimate the total experimental Gamow-Teller strengths. For stellar densities in excess of 107 g/cm³, ground-state electron-capture rates derived from the shell-model calculations using the KB3G (GXPF1a) interaction deviate on average less than 47% (31%) from those derived from experimental data for which the location of daughter states at low excitation energies are well established. For electron-capture rates derived from Gamow-Teller strengths calculated in QRPA, the deviations are much larger, especially at low stellar densities. Conclusions: Based on the limited set of test cases available for nuclei in the pf shell, shell-models using the GXPF1a and KB3G interactions can be used to estimate electron-capture rates for astrophysical purposes with relatively good accuracy. Measures of the uncertainties in these rates can serve as input for sensitivity studies in stellar evolution models. Ground-state electron-capture rates based on the QRPA formalism discussed in the paper exhibit much larger deviations than those based on the shell-model calculations and should be used with caution, especially at low stellar densities. [ABSTRACT FROM AUTHOR]

Positive and negative pulsed discharge plasma is generated above test liquid containing NaCl in Ar atmosphere, and the spatiotemporal variation of pH value in the liquid is visualized by a colorimetric method using bromothymol blue. Furthermore, polarity effects on H2O2 generation are examined by electrochemical calculation and a colorimetric method using titanium sulfate. When the positive pulsed discharge plasma is generated, the pH value of the liquid is decreased by H+ generation through the dissociation of H2O+, formed by the charge exchange reaction between Ar+ and H2O, while the pH value of the vicinity of an earthed electrode is increased by OH− generation through the electrolysis of water. When the negative pulsed discharge plasma is generated, the pH value of the liquid is increased by OH− generation and H+ reduction, respectively, through the reaction of hydrated electrons with H2O and H+, while the pH value in the vicinity of the earthed electrode is decreased by H+ generation through the electrolysis of water. The generation of H2O2 is found to be promoted when the positive pulsed discharge plasma is generated, and this increase rate of H2O2 is in approximate agreement with the calculated generation rate of H2O2, which is produced from OH generated by electrolysis. [ABSTRACT FROM AUTHOR]

Single crystal X-ray structure-characterized azine derivative (L) was explored for the selective detection of molybdenum (Mo(vi)) cations through green fluorescence emission. The Mo(vi) cation assisted inhibition of photo-induced electron transfer (PET) resulted in a 37-fold fluorescence enhancement via chelation enhanced fluorescence (CHEF) that allows detection of Mo(vi) with concentration as low as 2 × 10−9 M. The chelation of Mo(vi) cations by L has been confirmed by the single crystal X-ray structure of the resulting complex. The binding constant of L for Mo(vi) is fairly high (1.33 × 106 M−1). Moreover, L is very efficient for enrichment of Mo(vi) from aqueous solution. Density functional theoretical (DFT) studies substantiate the experimental results. [ABSTRACT FROM AUTHOR]

A new luminescent metal–organic framework, {[Cd3(HL)2(H2O)3]·3H2O·2CH3CN}n (1) (H4L = 1-(3,5-dicarboxylatobenzyl)-3,5-pyrazole dicarboxylic acid), has been synthesized by solvothermal reaction and characterized by infrared spectroscopy, powder X-ray diffraction, thermogravimetry measurements and so on. 1 shows a new trinodal (4,4,6)-connected topology. Importantly, 1 displays intense luminescence in the solid state and high luminescent sensitivity and selectivity for Fe3+, CrO42− and Cr2O72− ions in aqueous solution, making it a potential probe for detecting these substances. The quenching mechanisms are also further discussed in detail. In addition, further research on the adsorption of dyes shows that 1 can selectively adsorb Congo red dye from other dye molecules. [ABSTRACT FROM AUTHOR]

The verdazyl ‘pincer’ ligand, 1-isopropyl-3,5-dipyridyl-6-oxoverdazyl (dipyvd), coordinates iron to form a series of pseudooctahedral coordination compounds [Fe(dipyvd)2]n+ (n = 0–3). In the case where n = 2, the molecular geometry and physical and spectral properties are consistent with a low spin (S = 0) iron(ii) ion coordinated by two ferromagnetically coupled radical ligands. Upon one electron reduction, the room temperature effective magnetic moment of the complex jumps from μeff = 2.64 to μeff = 5.86 as a result of spin crossover of the iron atom combined with very strong ferromagnetic coupling of the remaining ligand centered unpaired electron with the metal center. The sign of the exchange is opposite to that observed in other high spin iron/radical ligand systems and appears to be a result of delocalization of the ligand unpaired electron across the whole molecule. The large change in magnetic properties, combined with a delocalized electronic structure and accessible redox potentials, suggests the utility of this and related systems in the development of novel molecular spintronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the flower-shaped silver nanoparticle was used as substrate to investigate the SERS effect of pesticide molecules under different treatment conditions. Due to the variation of molecular structure and molecular interactions with pH value and solvent type, the combination mode of molecules and metal surface and electron transfer also changes, resulting in different SERS effects with a certain regularity. It was demonstrated that the optimum pH values for test conditions are in the range of 6.66–11.11 due to the auxiliary of H + ions and undestroyed complete functional groups of ethion. Meanwhile, the ethion in the acetone was the best in the three solvents (ultrapure water, absolute ethanol and acetone). Under optimal conditions, ethion can be detected with a minimum detectable concentration of 10 −10 M. The regression model obtained through principal component analysis (PCA) can be used for rapid and precise detection of the concentration of ethion, suggesting the importance of condition optimization for SERS test. Therefore, the solvent environment can be effectively improved to promote non-resonance enhancement of chemical bonding between adsorbate and metal substrate and resonance enhancement of light-induced charge transfer in molecular-metal system by excitation light. The solvent environment has significant effect on the SERS sensor from chemical enhancement. [ABSTRACT FROM AUTHOR]

Although photochemistry-enabled escape of oxygen is a dominant atmospheric loss process at Mars today, ion outflow plays an essential role in the long-term evolution of Mars' atmosphere. Apart from heavy planetary ions such as O +, O2 +, and CO2 +, the loss of planetary protons is also important because it could be related to water loss. To study planetary proton loss due to solar wind interaction, we improve the 4-species (O +, O2 +, CO2 +, and H +) single-fluid magnetohydrodynamic (MHD) model of Mars, to a 5-species (separating planetary protons and solar wind protons) MHD model so that the two types of protons can be tracked separately. The global distributions of solar wind protons and planetary ions at low altitudes are investigated. The calculated planetary proton escape rates are larger than heavy ion loss rates and solar wind proton inflows for both solar maximum and minimum conditions. Planetary proton escape rates are 1-2 orders less than neutral hydrogen loss, suggesting that planetary protons could contribute to no >10% of the hydrogen loss under current conditions. By comparing normal cases with cases for which H-O charge exchange reactions or electron impact ionizations are switched off, we find that H-O charge exchange mainly affects densities at low altitudes, while impact ionizations exert great influence on escape rates at high altitudes. The overall results suggest the specific treatment of proton origins in models of Mars atmosphere escape provides better insight into the contributing processes, and should be included in future studies focusing on water's fate. [ABSTRACT FROM AUTHOR]

By analyzing the latitudinal distributions of ionospheric ions observed by the Detection of Electro‐Magnetic Emissions Transmitted from Earthquake Regions satellite at 670 km altitude in different seasons, we found that the large‐scale depletion of nighttime oxygen ions is prevalent at the low and middle latitudes of winter hemisphere (center ∼ 30°) under different geomagnetic conditions. The latitudinal width of the winter oxygen ion depletion (WOD) region is about 20°–60° at different longitudes, and its upper boundary latitudes are mostly lower than the midlatitude trough (|λ| ≥ 50°) of nighttime hydrogen ions (H+) near the plasmapause. In the WOD region, the density ratio of oxygen and hydrogen ions and that of their neutral densities (O and H) approximately agree with the chemical equilibrium relationship of charge exchange reactions (H + O+ ↔ H+ + O) predicted by previous theory, indicating that the charge exchange reactions are mainly responsible for the large‐scale oxygen ion depletion at the low and middle latitudes in winter hemisphere. Plain Language Summary: Previous studies focused on the nighttime midlatitude trough of ionospheric electrons (e−) and light ions (H+ and He+). Although the percentage of nighttime oxygen ions was found to decrease in winter hemisphere at 400 km altitude, it is not clear whether the winter oxygen ion depletion (WOD) is a common phenomenon in the topside ionosphere. Moreover, the mechanism of the WOD has not been understood clearly. Here, our statistical results indicate that the large‐scale depletion of nighttime oxygen ions is prevalent at the low and middle latitudes of winter hemisphere under different geomagnetic conditions. By analyzing the relationship among the latitudinal changes in the ion bulk velocity, densities and their neutral densities, we found that the charge exchange reactions mainly cause the nighttime oxygen ion depletion at the low and middle latitudes in winter hemisphere in the topside ionosphere. Key Points: The nighttime oxygen ions decrease remarkably at the low and middle latitudes of winter hemisphere in the topside ionosphereThe latitudes of large‐scale oxygen ion depletion (center ∼ 30°) are mostly lower than the midlatitude trough of nighttime hydrogen ionsThe winter depletion of nighttime oxygen ions is largely due to the charge exchange reactions between oxygen ions and atomic hydrogen [ABSTRACT FROM AUTHOR]

A chemical reaction mechanism of chlorine plasma under low-pressure conditions that is widely used in the literature is validated against the experimental data of Y. Wang and J. K. Olthoff [J. Appl. Phys. 85, 6358 (1999)] for an inductively coupled plasma reactor. The model used in the present study is a self-consistent two-dimensional fluid plasma model coupled with Maxwell's equations. The quantities of interest in the plasma are the fluxes and energy distribution functions of Cl2+ and Cl+ ions. We find that the charge exchange reaction between Cl+ and Cl2 that is typically included in chlorine plasma reaction mechanisms results in poor predictability of the model compared to experiments. Neglecting this reaction allows for a correct prediction of the dominant ion species in the low-pressure chlorine plasma and dependence of their fluxes on the gas pressure. Additionally, neglecting the charge exchange reaction allows for a rather accurate prediction of ion energy distribution functions at the grounded electrode. Overall, we conclude that the rate coefficient of the charge exchange reaction between Cl+ and Cl2 reported in the literature significantly exceeds what may in fact explain the role of this process in a low-pressure plasma discharge. [ABSTRACT FROM AUTHOR]

(1) Pions produced in the development of extended atmospheric cosmic ray air showers subsequently decay to muons. The measured yield of those muons is generally underestimated by current phenomenological models and event generators optimized for cosmic ray physics. The importance of those disagreements motivates the feasibility studies for testing these models at the Large Hadron Collider (LHC) energies, at the highest center-of-mass energies achievable in a laboratory. The interaction of a nucleus and a virtual pion created in a charge exchange reaction at the LHC is a similar process to those contributing to the development of air showers in case of cosmic rays. The crucial problem of such an analysis is the selection of charge exchange events with the highest possible efficiency and high purity from proton–proton collisions at the LHC. (2) For this we consider distributions of various measurable quantities given by event generators commonly used in cosmic ray physics. (3) We examine the expected distributions of energy deposited in different calorimeters of an LHC experiment. We consider the geometrical acceptance and energy resolution of the detectors at the Compact Muon Solenoid (CMS) experiment, as an example. We determine a working point cut from the various options for event selection, and compare signal and background predictions using different models for a representative simple observable, such as average transverse momentum or charge particle yield. (4) A set of event selection cuts along these considerations is proposed, with the aim of achieving optimal efficiency and purity. [ABSTRACT FROM AUTHOR]

The plume of a cathodic arc operated in atmospheric pressure gas is examined using an intensified camera and a spectrograph. A 0.2-J pulse arc is shown to generate a glowing jet $\approx 10$ mm in extent. Images recorded in the first microseconds after ignition show that the jet has a smaller core \approx 2$ mm in length. A spatially resolved Stark broadening measurement is performed along the jet core. The measured electron density is 1– 2 \times 10^{20} \text{m}^{\vphantom {R^{R}}-3} . A model for the cathodic arc plasma–gas interaction is presented. The obtained equilibrium between the forward and reverse charge exchange processes is suggested as enabling the extended jet core. [ABSTRACT FROM PUBLISHER]

The AEgIS experiment aims at producing antihydrogen (and eventually measuring the effects of the Earth gravitational field on it) with a method based on the charge exchange reaction between antiproton and Rydberg positronium. To be precise, antiprotons are delivered by the CERN Antiproton Decelerator (AD) and are trapped in a multi-ring Penning trap, while positronium is produced by a nanoporous silica target and is excited to Rydberg states by means of a two steps laser excitation. New Monte Carlo simulations are presented in this paper in order to investigate the current status of the AEgIS experiment [1] and to interpret the recently collected data [2]. [ABSTRACT FROM AUTHOR]

Current values of the neutron lifetime, determined by two entirely distinct measurement techniques of comparable precision, differ to a statistically significant degree, a result which has become known as the neutron lifetime anomaly. In a previous publication we have shown that the discrepancy can be resolved by taking account of electron transfer charge exchange reactions between residual gases and final state protons stored in a quasi-Penning trap. In this article we analyze unique experimental data obtained during the course of the first published neutron lifetime measurement that used a proton trap. These data employed trapping times greater by a factor of a thousand than became conventional in later experiments. The data show that significant event losses occur, probably due to residual gas other than molecular hydrogen or helium. Additionally, the molecular ion H2+ produced by charge exchange in H2 undergoes secondary molecular reactions, producing the molecular ion H3+ and the ion HeH+ which is also produced by secondary reactions in helium. These ions could result in event losses depending on the energy and time-of-flight acceptance windows. Energy losses are evaluated and ionic compositions are quantitively assessed as functions of trapping time and residual gas density to account for an energy spectrum obtained using a silicon surface barrier detector. The spectrum is strongly influenced by charge exchange, secondary molecular reactions and backscattering in the detector dead layer. [ABSTRACT FROM AUTHOR]

Background: Stellar electron-capture reactions on medium-heavy nuclei are important for many astrophysical phenomena, including core-collapse and thermonuclear supernovae and neutron stars. Estimates of electroncapture rates rely on accurate estimates of Gamow-Teller strength distributions, which can be extracted from charge-exchange reactions at intermediate beam energies. Measured Gamow-Teller transition strength distributions for stable pf:shell nuclei are reasonably well reproduced by theoretical calculations in the shell model, except for lower mass nuclei where admixtures from the sd shell can become important. Purpose: This paper presents a β+ charge-exchange experiment on 45Sc, one of the lightest pf-shell nuclei. The focus was on Gamow-Teller transitions tofinal states at low excitation energies, which are particularly important for accurate estimations of electron-capture rates at relatively low stellar densities. The experimental results are compared with various theoretical models. Method: The double-differential cross section for the 45Sc(t, 3He +γ) reaction was measured using the NSCL Coupled-Cyclotron Facility at 115 MeV/u. Gamow-Teller contributions to the excitation-energy spectra were extracted by means of a multipole-decomposition analysis, γ rays emitted due to the deexcitation of 45Ca were measured using GRETINA to allow for the extraction of Gamow-Teller strengths from very weak transitions at low excitation energies. Results: Gamow-Teller transition strengths to 45Ca were extracted up to an excitation energy of 20 MeV, and that to the first excited state in 45Ca at 174 keV was extracted from the γ-ray measurement, which, even though weak, is important for the astrophysical applications and dominates under certain stellar conditions. Shell-model calculations performed in the pf shell-model space with the GXPF1A, KB3G, and FPD6 interactions did not reproduce the experimental Gamow-Teller strength distribution, and a calculation using the quasiparticle random phase approximation that is often used in astrophysical simulations also could not reproduce the experimental strength distribution. Conclusions: Theoretical models aimed at describing Gamow-Teller transition strengths from nuclei in the lower pf shell for the purpose of estimating electron-capture rates for astrophysical simulations require further development. The likely cause for the relatively poor performance of the shell-model theory is the influence of intruder configurations from the sd shell. The combination of charge-exchange experiments at intermediate beam energy and high-resolution γ-ray detection provides a powerful technique to identify weak transitions to low-lying final states that are nearly impossible to identify without the coincidences. Identification of these weak low-lying transitions is important for providing accurate electron-capture rates for astrophysical simulations [ABSTRACT FROM AUTHOR]

A desoxomolybdenum(iv) complex containing bulky hydrophobic groups and NH…S hydrogen bonds, (Et4N)[MoIV(OSitBuPh2)(1,2-S2-3,6-{(4-tBuC6H4)3CCONH}2C6H2)2], was synthesized. This complex promotes the oxygen-atom-transfer (OAT) reaction of DMSO by efficient uptake of the substrate into the active center. The clean OAT reaction of Me3NO is also achieved. [ABSTRACT FROM AUTHOR]

A new diagnostic has been developed on DIII-D that determines the impurity poloidal rotation from the poloidal asymmetry in the toroidal angular rotation velocity. This asymmetry is measured with recently added tangential charge exchange viewchords on the high-field side of the tokamak midplane. Measurements are made on co- and counter-current neutral beams, allowing the charge exchange cross section effect to be measured and eliminating the need for atomic physics calculations. The diagnostic implementation on DIII-D restricts the measurement range to the core (r/a < 0.6) where, relative to measurements made with the vertical charge exchange system, the spatial resolution is improved. Significant physics results have been obtained with this new diagnostic; for example, poloidal rotation measurements that significantly exceed neoclassical predictions. [ABSTRACT FROM AUTHOR]

C60 is a scaffold or an electron acceptor  depending on the number of addends. The role of different fullerene subunits is dramatically different in a supramolecular photosynthetic model obtained from a C60 monoadduct bearing an imidazole moiety and a C60 hexa‐adduct decorated with 12 peripheral metalloporphyrins. In their Full Paper on page 223 ff., J. ‐F. Nierengarten, N. Armaroli et al. show that only the monosubstituted C60 derivative plays an active role (electron acceptor) in the cascade of photoinduced events. [ABSTRACT FROM AUTHOR]

Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the u-channel, as discussed in the first Backward angle (u-channel) Physics Workshop. In particular, we discuss backward angle measurements and their theoretical description via both hadronic models and the collinear factorization approach, and discuss planned future measurements of u-channel physics. Finally, we propose outstanding questions and challenges for u-channel physics. [ABSTRACT FROM AUTHOR]

In a recent experiment, the repair efficiency of DNA thymine cyclobutane dimers (T＜＞T) on UV excitation of 8-oxoG base paired either to C or A was reported. An electron transfer mechanism from an excited charge transfer state of 8-oxoG–C (or 8-oxoG–A) to T＜＞T was proposed and 8-oxoG–A was found to be 2–3 times more efficient than 8-oxoG–C in repair of T＜＞T. Intra base pair proton transfer (PT) in charge transfer (CT) excited states of the base pairs was proposed to quench the excited state and prevent T＜＞T repair. In this work, we investigate this process with TD-DFT calculations of the excited states of 8-oxoG–C and 8-oxoG–A base pairs in the Watson–Crick and Hoogsteen base pairs using long-range corrected density functional, ̉B97XD/6-31G* method. Our gas phase calculations showed that CT excited state (1ππ*(CT)) of 8-oxoG–C appears at lower energy than the 8-oxoG–A. For 8-oxoG–C, TD-DFT calculations show the presence of a conical intersection (CI) between the lowest 1ππ*(PT–CT) excited state and the ground state which likely deactivates the CT excited state via a proton-coupled electron transfer (PCET) mechanism. The 1ππ*(PT–CT) excited state of 8-oxoG–A base pair lies at higher energy and its crossing with ground state is inhibited because of a high energy gap between 1ππ*(PT–CT) excited state and ground state. Thus the gas phase calculations suggest the 8-oxoG–A would have longer excited state lifetimes. When the effect of solvation is included using the PCM model, both 8-oxoG–A and 8-oxoG–C show large energy gaps between the ground state and both the excited CT and PT–CT states and suggest little difference would be found between the two base pairs in repair of the T＜＞T lesion. However, in the FC region the solvent effect is greatly diminished owing to the slow dielectric response time and smaller gaps would be expected. [ABSTRACT FROM AUTHOR]

Abstract: A detailed study using the ab initio DFT-based calculations of the electronic and optical properties of pure and Mn4+ doped Ba2LaNbO6 is presented in this paper. Comparison of the calculated electronic bands structure, density of states diagrams, and dielectric functions for the pure and doped crystal reveals the changes induced by the Mn4+ impurity ions. In addition, the energy levels of the Mn4+ ion in the ordered perovskite Ba2LaNbO6 are calculated by the exchange charge model (ECM) of crystal field theory and compared with the experimental data that has been presented in the literature. The calculated Mn4+ energy levels are in good agreement with the experimental spectra. Additionally, the excitation band shapes of the 4A2g(4F)–4T2g(4F) and 4A2g(4F)–4T1g(4F) transitions are modeled to estimate the zero-phonon lines (ZPL) positions and the effective number of phonons, which are involved in the corresponding excitation transition. The results of our calculations yield the crystal field parameter of Dq=1780cm−1 and Racah parameters B=670 and C=3290cm−1, with C/B=4.9 for the Mn4+ ion in the double-perovskite Ba2LaNbO6. [Copyright &y& Elsevier]

Abstract: We describe a setup for studies of dissociation dynamics of multiply charged molecules formed due to highly charged ion impact. The setup consists of a multihit, position-sensitive, time of flight measurement system along with an electrostatic analyzer with offset detector. Brief description of different components of the setup and electronics for multihit data acquisition is presented in this paper. Coulomb explosion of multiply ionized N2 and charge exchange studies on Ar with highly charged projectile ion is carried out to test the performance of the spectrometer and its multifold coincidence capabilities. [Copyright &y& Elsevier]

These lectures, held at a school at the Galileo Galilei Institute for Theoretical Physics, give a survey of the formalism, the methods and achievements of nuclear direct reaction theory. After recapitulating the principles of quantum scattering theory, projection techniques are used to reduce the complexities of nuclear reactions to the manageable level of a set of a few selected coupled channels interacting via effective operators. Direct reactions are introduced as fast reactions proceeding preferentially through the excitation of doorway components of the nuclear many-body configurations, corresponding to a separation of scales in energy and momentum transfer. The concept of the optical model is introduced and applied to elastic scattering on nuclei. The coupled channel T-matrix formalism is discussed for pion-induced reactions on the nucleon. Applications of direct reaction to theory are illustrated for transfer reactions, inelastic scattering, and single and double charge exchange reactions with light and heavy ions. [ABSTRACT FROM AUTHOR]

The current rate constants agree reasonably well with the Coulomb crystal measurements for both the NH SB 3 sb and ND SB 3 sb reactions given the absolute uncertainties. The rate constants were measured by monitoring the first order decay of Xe SP + sp ( SP 2 sp P SB 3/2 sb ) as a function of the concentration of NH SB 3 sb /ND SB 3 sb . Ions were produced using an electron impact ion source yielding both ground Xe SP + sp ( SP 2 sp P SB 3/2 sb ) and excited state Xe SP + sp ( SP 2 sp P SB 1/2 sb ), then mass-selected and injected into a flow tube maintained at ~0.3 Torr of fast flowing helium gas. [Extracted from the article]

The neutral particles generated by charge exchange reactions can play an important role in erosion of first wall materials in fusion devices. In order to measure the flux and energy of neutral particles to the first wall, a low-energy neutral particle analyzer (LENPA) based on the time-of-flight method has been developed and successfully applied on the Experimental Advanced Superconducting Tokamak (EAST)' to measure the neutrals with an energy of 20–3000 eV. The LENPA works in the counting mode, and the signal of photons is used as the reference for the flight time of neutrals. The energy spectrum of low-energy neutral particles on EAST has been obtained for the first time. The new diagnostics can help in understanding the neutral particle generation and deposition on the first wall materials in tokamaks under different plasma conditions. [ABSTRACT FROM AUTHOR]

An ultrafast charge exchange spectroscopy (UFCES) system has been designed for measuring fluctuations in ion temperature and toroidal rotation velocity. The UFCES on the KSTAR tokamak is a powerful tool for investigating plasma instabilities and long-wavelength turbulence related to ion temperature gradient and flow. The UFCES system is designed to measure the C VI line (n = 8 → 7, λ0 = 529.05 nm) from the charge exchange reaction between a deuterium-heating neutral beam and the intrinsic carbon impurity in KSTAR. The ion temperature and toroidal rotation velocity at two radial positions will be observed simultaneously with UFCES. The key difference between the UFCES system and conventional charge exchange spectrometers is the application of high-throughput collection optics, a high-efficiency transmission grating combined with prisms, and a high-speed detector. We use a comprehensive spectrum simulation code with input parameters of KSTAR's plasmas and a neutral beam injection system to estimate the performance of the designed UFCES system. The results simulated with the code show that the diagnostic achieves a turbulence-relevant time resolution of 10 µs with a high enough signal-to-noise ratio. Furthermore, a preliminary test is performed using a complementary metal–oxide semiconductor camera and Ne spectral lamp to confirm the linear dispersion and curvature radius. [ABSTRACT FROM AUTHOR]

The results of a numerical simulation of the dynamics of the airglow of the atomic oxygen red line (630 nm) due to ionospheric heating by high-power, high-frequency (HF) radio emission are presented. The simulation was based on a system that incorporates an equation for the electron temperature Te (thermal conductivity) with a localized heating source near the reflection point of the pump wave; an equation to balance the ion concentration in molecular oxygen which emerges from the charge exchange reaction (О+ + О2 → + О); and an equation for the concentration of oxygen atoms in the excited state O(1D), which results from the dissociative recombination ( + е− → О + О(1D)) and is responsible for the airglow. The height distributions of molecular (O2) and atomic (O) oxygen were taken from the NRLMSISE-00 empirical model of the atmosphere, and the profiles of the electron content Ne were taken from the International Reference Ionosphere (IRI) model modified according to the 2010 and 2012 experimental data from the SURA ionospheric heating facility. The results have been compared with experimental data. The calculations make it possible to interpret the experimentally observed suppression of the background airglow during ionospheric heating by a high-power radio wave and the "afterglow" effect upon the cessation of heating. [ABSTRACT FROM AUTHOR]

An Imaging Neutral Particle Analyzer (INPA) diagnostic has been designed for the ASDEX Upgrade (AUG) tokamak. The AUG INPA diagnostic will measure fast neutrals escaping the plasma after charge exchange reactions. The neutrals will be ionized by a 20 nm carbon foil and deflected toward a scintillator by the local magnetic field. The use of a neutral beam injector (NBI) as an active source of neutrals will provide radially resolved measurements, while the use of a scintillator as an active component will allow us to cover the whole plasma along the NBI line with unprecedented phase-space resolution (<12 keV and 8 cm) and a fast temporal response (up to 1 kHz with the high resolution acquisition system and above 100 kHz with the low resolution one), making it suitable to study localized fast-ion redistributions in phase space. [ABSTRACT FROM AUTHOR]

The differential cross sections of the charge exchange reaction d p → (p p) n has been measured at 1.75 GeV/c per nucleon for small transferred momenta using the one arm magnetic spectrometer STRELA at the Nuclotron accelerator in JINR Dubna. The ratio of the differential cross section of the charge exchange reaction d p → (p p) n to that of the n p → p n elementary process is discussed in order to estimate the spin-dependent part of the n p → p n charge exchange amplitude. The n p → p n amplitude turned out to be predominantly spin-dependent. [ABSTRACT FROM AUTHOR]

Gas giant exoplanets orbiting at close distances to the parent star are subjected to large radiation and stellar wind fluxes. In this paper, hydrodynamic simulations of the planetary upper atmosphere and its interaction with the stellar wind are carried out to understand the possible flow regimes and how they affect the Lyα transmission spectrum. Following Tremblin and Chiang, charge exchange reactions are included to explore the role of energetic atoms as compared to thermal particles. In order to understand the role of the tail as compared to the leading edge of the planetary gas, the simulations were carried out under axisymmetry, and photoionization and stellar wind electron impact ionization reactions were included to limit the extent of the neutrals away from the planet. By varying the planetary gas temperature, two regimes are found. At high temperature, a supersonic planetary wind is found, which is turned around by the stellar wind and forms a tail behind the planet. At lower temperatures, the planetary wind is shut off when the stellar wind penetrates inside where the sonic point would have been. In this regime mass is lost by viscous interaction at the boundary between planetary and stellar wind gases. Absorption by cold hydrogen atoms is large near the planetary surface, and decreases away from the planet as expected. The hot hydrogen absorption is in an annulus and typically dominated by the tail, at large impact parameter, rather than by the thin leading edge of the mixing layer near the substellar point. [ABSTRACT FROM AUTHOR]

Total electron scattering cross sections for pyrazine in the energy range 10-500 eV have been measured with a new magnetically confined electron transmission-beam apparatus. Theoretical differential and integral elastic, as well as integral inelastic, cross sections have been calculated by means of a screening-corrected form of the independent-atom representation (IAM-SCAR) from 10 to 1000 eV incident electron energies. The present experimental and theoretical total cross sections show a good level of agreement, to within 10%, in the overlapping energy range. Consistency of these results with previous calculations (i.e., the R-matrix and Schwinger Multichannel methods) and elastic scattering measurements at lower energies, below 10 eV, is also discussed. [ABSTRACT FROM AUTHOR]

The article profiles Massachusetts Institute of Technology (MIT) chemistry professor Daniel G. Nocera. It says that he was inspired by chemistry and physics teachers to take up a bachelor's degree in chemistry at Rutgers University in 1974 and started his doctoral studies in 1979. It discusses several chemical reactions he addressed including the transfer of two electrons to an atom of hydrogen, the orchestration of anaerobic metabolism in algae, and the proton-coupled electron transfer (PCET).

The Regge features of elastic K±N → K±N, and charge exchange K - p → K0n and K + n → K0p reactions are described by using a combined analysis of all these channels at high momenta. Based on the meson exchanges in the t -channel with their decays to a KK pair allowed, the exchanges of ρ (775) + ω (782) are excluded in contrast to existing model calculations and the present paper follows a new scheme for the meson exchanges a0 (980) + ϕ (1020) + f2 (1275) + a2 (1320) Reggeized for the forward elastic-scattering amplitude together with Pomeron. The charge exchange reactions are described by a0 (980) + a2 (1320) exchanges in the t -channel. Dominance of the isoscalar f2 and Pomeron exchanges beyond PLab ≈ 3 GeV/c is shown in the elastic process. Both the isovector a0 and a2 exchanges in charge exchange reactions play the respective roles in the low- and high-momenta region. Differential and total cross sections are presented to compare with existing data. A discussion is given to the polarization of K-p → K-p at PLab = 10 GeV/c and K-p → K0n at PLab = 8 GeV/c. [ABSTRACT FROM AUTHOR]

In this work, the suitability of atmospheric pressure photoionization (APPI) has been assessed for the determination of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) by gas chromatography–high-resolution mass spectrometry (GC-HRMS). The APPI of target compounds has been tested in both positive and negative ion modes. Under positive ion mode, the analytes generated the molecular ion, which was favoured using dopants that promote charge exchange gas-phase reactions (i.e., benzene), while in negative ion mode, the ion [M−Cl+O]− for PCDFs and dl-PCBs were mainly formed, providing the best results using benzene and diethyl ether as dopants, respectively. Concerning PCDDs, highly chlorinated congeners were mainly ionized by means of the [M−Cl]− ion, whereas [M−Cl+O2]− was the base peak for tetraCDD and [M−Cl+O]− for penta- and hexaCDDs. Method quality parameters, in accordance with the current EU Regulation guidelines for food and feed analysis, showed the good performance of the two GC-APPI-HRMS (Orbitrap) methods since they provided high detection capability (low fg levels), good linearity, and satisfactory precision (RSD% < 9%). In addition, the GC-APPI-HRMS (Orbitrap) methods were validated by analysing selected environmental and feed samples and the results were compared to those obtained using conventional GC-EI-HRMS, demonstrating the good performance in the analysis of the target compounds. Hence, the GC-APPI-HRMS technique can be proposed as alternative to the conventional methods for the determination of PCDD/Fs and dl-PCBs in environmental and feed matrices. [ABSTRACT FROM AUTHOR]

The nuclear isotopic structure can be understood easily via the intermediate-energy charge exchange reactions of (p, n) and (3 He, t) type. In the current contribution, we present some results for charge exchange reactions induced by 3He on targets lying in mass region 1 8 ≤ A ≤ 2 0 8 within the theoretical framework of plane wave impulse approximation (PWIA) and distorted wave impulse approximation (DWIA). Here, the recoil effects in PWIA have also been considered. Particularly, the angular distributions and the unit cross-sections have been calculated and compared with the available data. Further, the importance of inclusion of the exchange contribution in these reactions is also considered, which eventually enhance the matching with data. [ABSTRACT FROM AUTHOR]