Range Of Ions Research Articles

Proton Beam Therapy-Based Computation in the Treatment of Human Ovarian and Liver Cancer using Srim

Proton beam therapy is a promising technique used to cure various types of cancer diseases in the human body. This technique can selectively damage cancer cells while leaving surrounding cells unaffected thereby minimizing collateral damage to the healthy cells. The position and the width of the cancerous cells are determined to calculate the energy required to destroy the affected cells. The energy loss to the damaged cells and other body parts is calculated separately with high accuracy. Computational analysis indicates that proton beams with energies of 46 MeV, 47 MeV, and 48 MeV effectively destroy localized cancerous cells of the ovary from the epithelial cells to the more invasive cancerous growth while proton beam energy range of 50 MeV to 89 MeV should be considered for the treatment of liver cancer of both the periphery tumours and tumours in the hilum. Transport of ions in matter (TRIM) data shows that more than 80% of proton energy is given off during ion bombardment at Bragg’s peak, while the remaining percentage is lost by phonon production and by recoils.

Functionalized gold nanorods turn-on chemosensor for selective detection of Cd2+ ions, bio-imaging, and antineoplastic evaluations

A colorimetric turn-on chemosensor based on gold nanorods, Au NRs, has been developed to enable rapid, facile, and simultaneous detection of hazardous metal ions. This study involved the functionalization of gold nanorods with (9,10-dioxo-9,10-dihydro-anthracen-1-yl)-dithiocarbamic acid (DTAD) through the utilization of synthetic photo-irradiation and ultrasound techniques. Various spectroscopic methods were employed to characterize both the synthesized gold nanorods and the chemosensor. The optical response of this sensor was investigated with respect to a range of metal ions, including Mg2+, K+, Ca2+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Pb2+. The results reveal that the DTAD-functionalized gold nanorods chemosensor effectively discriminates all the investigated metal ions, with Cd2+ ions exhibiting higher sensitivity and selectivity compared to the other metal ions. Moreover, the anticancer impact of both gold nanorods and DTAD-functionalized gold nanorods was investigated on a panel of cell lines as breast cancer (MCF-7), liver cancer (HepG-2), and colon cancer (Caco-2) using MTT assay. Further, the morphological features and Annexin V using flow cytometry were carried. Comparative analysis with a free chemosensor showed that fluorescence images of living cells were notably brighter in the presence of Cd2+, highlighting the efficacy of DTAD-functionalized gold nanorods as a fluorescent biosensor for Cd2+ ions. Additionally, the in vitro anticancer study showed that gold nanorods significantly inhibited the growth of all cancer cells than DTAD-functionalized gold nanorods with best antiproliferative effect on HepG-2 hepatocellular carcinoma with IC50 values equal to 1.971 ± 1.28, 40.95 ± 2.56 µg/mL, respectively, compared to DOX. Also, the alteration in the HepG-2 morphological shape and Annexin V results confirmed the great antineoplastic effect of Au NRs than DTAD-Au NRs.

The effect of efficient high-dose-rate plasma immersion ion implantation on microstructure and properties of 8Cr4Mo4V steel

8Cr4Mo4V steel was implanted with 20 keV nitrogen ions dose rates with fluences between 2.60 × 1017 ions/cm2·h and 1.04 × 1018 ions/cm2·h. The samples were analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), elemental dispersive spectroscopy (EDS), secondary ion mass spectroscopy (SIMS), auger electron spectroscopy (AES) and nanoindentation test. The stopping and range of ions in matter (SRIM) code was used to calculate vacancies and displacements distributions. The results reveal that the implanted surface layer contains the phase composition of Fe(M) and Fe2–3N. The peaks of the samples with a dose rate from 2.60 × 1017 to 7.85 × 1017 ions/cm2·h are broadened and slightly shift to left by 0.777° towards comparing to the dose rate of 1.04 × 1018 ions/cm2·h. A significant improvement in roughness of Ra (∼10.4 nm) is attained for the dose rate of 7.85 × 1017 ions/cm2·h. The lattice parameters of the smallest grain size, the highest micro-strain and dislocation density of 11.78 nm, 7.716 × 10−3 and 1.559 × 1016 /m2 respectively were obtained for the dose rate of 5.18 × 1017 ions/cm2·h. There exists a deep diffusion zone of about 400 nm for the dose rate of 7.85 × 1017 ions/cm2·h and 1.04 × 1018 ions/cm2·h, which is 4 times deeper than other implanted samples. Furthermore, the nanohardness of implanted samples improved notably as well, especially at the dose rate of 8.64 × 1017 ions/cm2·h, reaches to a higher value of 16.3 GPa, which is 46.8 % higher than that of non-implanted sample of 11.1 GPa, implies that the properties of samples strongly affected by the implantation dose rate.

Analysis of Basal Plane Dislocation Motion Induced By P+ Ion Implantation Using Synchrotron X-Ray Topography

Silicon Carbide (SiC) is a promising wide bandgap semiconductor for future power devices since it has a wide bandgap, high breakdown voltage and good thermal stability [1]. The most mature method to perform selective area doping in 4H-SiC epiwafers during fabrication is ion implantation [2]. However, such implantation processes employing high energy ions can damage the lattice in the epilayers that can subsequently lead to formation and migration of basal plane dislocations (BPDs) which are known to be detrimental to the performance of the devices [3-4]. Implantation processes are typically conducted under room temperature (RT) conditions, but high temperature (HT) implantation is favorable when the dose level is high [5]. Oxide layer for blocking purpose is inevitable since photoresist can barely remain intact under such high temperature, which will increase the time, cost, and complexity [6-7].Here, we will primarily emphasize the motion of the BPDs under stress from RT implantation. 1.2 kV-rated 4H-SiC PiN diodes with junction termination extension (JTE) annealed with same conditions have been successfully fabricated by implantation with different dose levels and concentration profiles under room temperature and at 600 ˚C. Concentration profiles simulated by Stopping and Range of Ions in Matter (SRIM) are shown in Fig.1(a) [8]. The JTEs were implanted with lower concentrations. Synchrotron monochromatic beam X-ray topography (SMBXT) has been performed to characterize the defects induced by implantation and annealing process. Topographs of PIN diodes are shown in Fig.1 (b)-(h). For the diodes implanted with 1x under RT and HT, there is no evidence of dislocations generated due to implantation and annealing. However, formation of BPD half loops, as highlighted in the red and yellow boxes, can be observed from the edge of the device when the dose level is elevated to 5x and 9x. In addition to that, the basal plane density (BPD) density of 5x RT Box due to implantation and annealing is much more significant than that of 5x RT and 9x RT, indicating that concentration profile can affect the defect generation. Fig.1 (e) shows topograph of PiN diode implanted with 5x under high temperature. The absence of BPDs compared to the RT implanted device to the same concentration profile suggests the generation of BPD is suppressed by the high temperature condition. In 5x RT Box device, opposite sign BPDs are nucleated from opposite edges of device, as indicated in Fig.1 (f)&(g). Here, we will analyze the motion of dislocations generated by ion implantation and annealing.Reference:[1] J. Guo, Y. Yang, B. Raghothamachar, T. Kim, M. Dudley, J. Kim, J. Cryst. Growth[2] F. Roccaforte, P. Fiorenza, M. Vivona, G. Greco, F. Giannazzo, Materials 14(14) (2021) 3923.[3] K. Konishi, R. Fujita, Y. Mori and A. Shima, Semiconductor Science and Technology 2018 Vol. 33 Issue 12[4] M. Nagano, H. Tsuchida, T. Suzuki T. Hatakeyama, J. Senzaki and K. Fukuda, J. Appl. Phys. 108, 013511 (2010)[5] S. Mancini, S. Y. Jang, Z. Chen, D. Kim, Y. Liu, B. Raghothamachar, M. Kang, A. Agarwal, N. Mahadik, R. Stahlbush, M. Dudley, W. Sung, proceeding of 2022 IEEE International Reliability Physics Symposium (IRPS). (accepted)[6] T. Kimoto, J. A. Cooper. John Wiley & Sons Singapore Pte. Ltd. 2014. pp. 197-200[7] D. Kim, N. Yun and W. Sung, 2021 IEEE International Reliability Physics Symposium (IRPS), 2021, pp. 1-4, doi: 10.1109/IRPS46558.2021.9405109[8] J. F. Ziegler, M.D. Ziegler, J.P. Biersack, Nucl Instrum Methods Phys Res B, Volume 268, Issues 11–12, June 2010, Pages 1818-1823 Figure 1

The multifarious MerR family of transcriptional regulators.

The MerR family of transcriptional regulators includes a variety of bacterial cytoplasmic proteins that respond to a wide range of signals, including toxins, metal ions, and endogenous metabolites. Its best-characterized members share similar structural and functional features with the family founder, the mercury sensor MerR, although most of them do not respond to metal ions. The group of "canonical" MerR homologs displays common molecular mechanisms for controlling the transcriptional activation of their target genes in response to inducer signals. This includes the recognition of distinctive operator sequences located at suboptimal σ70 -dependent promoters. Interestingly, an increasing number of proteins assigned to the MerR family based on their DNA-binding domain do not match in structure, sequence, or mode of action with any of the canonical MerR-like regulators. Here, we analyzed several members of the family, including this last group. Based on a phylogenetic analysis, and similarities in structural/functional features and position of their target operators relative to the promoter elements, we propose to assign these "atypical/divergent" MerR regulators to a phylogenetically separated group. These atypical/divergent homologs represent a new class of transcriptional regulators with novel regulatory mechanisms.

Quantum-mechanical four-body versus semi-classical three-body theories for double charge exchange in collisions of fast alpha particles with helium targets

AbstractWithin the two-channel distorted wave second-order perturbative theoretical formalism, we study capture of both electrons from helium-like targets by heavy nuclei as projectiles at intermediate and high impact energies. The emphasis is on the four-body single-double scattering (SDS-4B) method and the three-body continuum distorted wave impact parameter method (CDW-3B-IPM). The SDS-4B method deals with the full quantum-mechanical correlative dynamics of all the four interactively participating particles (two electrons, two nuclei). The CDW-3B-IPM is a semi-classical three-body independent particle model (one electron, two nuclei), using a combinatorial calculus to describe double capture by a product of two uncorrelated probabilities, integrated over impact parameters. Both theories share a common feature in having altogether two electronic full Coulomb continuum wave functions. One such function is centered on the projectile nucleus in the entrance channel, whereas the other is centered on the target nucleus in the exit channel. These two methods satisfy the correct initial and final Coulomb boundary conditions in the asymptotic region of scattering, at infinitely large inter-particle separations. Yet, it is presently demonstrated that most of the available experimental data on total cross sections for the double capture from helium by alpha particles distinctly favor the SDS-4B method. This is especially true at intermediate energies. Such energies are critically important in versatile applications under the general umbrella of ion transport in matter, including thermonuclear fusion (plasma physics) and ion therapy (medicine).

Spectroscopic ellipsometry modelling of Cr+ implanted copper oxide thin films

In this paper, we present modelling of spectroscopic ellipsometry data. The measured samples are thin films of copper oxides modified with the ion implantation method. The samples were prepared using reactive magnetron sputtering. Thin films of CuO and Cu4O3 were deposited and subjected to Cr ion implantation with an energy of 15 keV and a dose of 5 × 1016 ions/cm2. The decrease in crystallinity of the thin film as a result of the implantation was inspected with X-ray diffraction measurements. The implantation of Cr+ ions was simulated using the Stopping and Range of Ions in Matter software by Ziegler and Biersack. Ion beam energy of 15 keV was simulated to estimate the distribution of Cr ions in the copper oxides thin films. Optical parameters, such as refractive index, extinction coefficient, and absorption coefficient of the thin films, were investigated with spectroscopic ellipsometry. Multilayered models based on Tauc–Lorentz oscillators were developed for both oxides. Analysis of the optical properties showed that the ion implantation with Cr decreased the absorption of copper oxides thin films and the modelling proved that the material properties of top layers changed the most.

Features of thermal processes and the influence of pulsed heating of surface layers of titanium on the diffusion transfer of dopants during high-intensity ion implantation

Methods for modification of surface and near-surface layers of materials and coatings by ion beamshave prospects for application in many fields of science and technology. The method of high-intensityimplantation by high-power density ion beams with submillisecond duration involves significantpulsed heating of the irradiated target’s surface layer, followed by its rapid cooling due to heatremoval into the material due to thermal conductivity and the implementation of repetitively-pulsedradiation-enhanced diffusion of atoms to depths significantly exceeding the projective ion range. Thispaper considers features of thermal processes and the effect of pulsed heating of near-surface titaniumlayers on diffusion transfer under conditions of synergy of high-intensity titanium ion implantationand energy impact of a high-power density repetitively-pulsed beam on the surface to increase iondoping depth due to radiation-enhanced diffusion under conditions of limited heating of the entiresample. The paper presents the data of numerical simulation of dynamic changes in temperature fieldsin titanium and titanium self-diffusion under the action of ion beams with a submillisecond durationand a pulse power of tens of kW/cm2 and fluence of ions in a pulse 1.25×1015 ion/cm2.

New fluorescent manganese(III) phthalocyanines bearing non-peripherally octa-(3-pyridin-3-ylpropoxy) and (4-pyridin-3-ylpropoxy) for the sensitive determination of Pd2+ in real water samples

In this study, 3,6-bis(3-pyridin-3-ylpropoxy)phthalonitrile (1), 3,6-bis(3-pyridin-4-ylpropoxy)phthalonitrile (2), {1,4,8,11,15,18,22,25-octakis[3-pyridin-3-ylpropoxy]-phthalocyaninato} manganese(III) chloride (1a), {1,4,8,11,15,18,22,25-octakis[3-pyridin-4-ylpropoxy]-phthalocyaninato} manganese(III) chloride (2a) were synthesized and characterized with various techniques. Then, the affinities of the two new fluorescent manganese(III) phthalocyanines 1a and 2a with a range of metal ions were investigated. Manganese(III) phthalocyanine (MnPc) 1a selectively forms a complex with Pd2+ which exhibits intense fluorescence quenching (λex/λem = 390/466 nm). 1a has been used as a fluorescent reagent to determine Pd2+ in real water samples. The samples of spiked water showed no matrix effect for Pd2+ determination in the working conditions. The proposed method, which is simple, fast, and sensitive, is good enough to recover Pd2+ at a concentration of 13.3 ng/mL. The detection limit (LOD) and the quantification limit (LOQ) of method are 3.0 ng/mL, and 9.1 ng/mL, respectively. The inter and intra-day precisions of method (RSD %) are 1.9 and 2.9. Therefore, 1a can detect and determine the hazardous pollutant Pd2+ in real water samples.

Molecular dynamics simulation of 100 keV argon ion radiation effects in metals and comparison with stopping and range of ions in matter code

Simulation is essential to analyse radiation-induced effects because energetic ions have short transit times within materials (Ar ions of 1 keV and 100 keV have transit times of 0.29 picoseconds and 29 femtoseconds respectively, through a 25 nm Al film). The binary collision approximation (BCA) is extensively used in simulations to study damage caused by energetic ions due to its computational efficiency. Stopping and Range of Ions in Matter (SRIM), a widely used Monte Carlo software using BCA, provides accurate ion ranges consistent with experiments. Molecular dynamics simulations are powerful computational method, where classical equations of motion are solved to track atomic movements from radiation damage, but computational resources required are heavier for this method. In our current effort, the energy transfer from 100 keV Ar+ to metal targets is analysed as a function of target properties, including melting temperature and atomic density, using these two methodologies. A detailed investigation of 100 keV Ar+ ion impact on metal targets is done using the classical Molecular Dynamics simulation program ‘MDRange’, which uses the Recoil Interaction Analysis (RIA) approximation, where the interaction between the ion and its closest neighbours is considered via a two-body potential. The correlation of energy transferred to the metal with the target properties is examined considering the physical approximations of each technique.

Using SRIM code for calculating Bragg curve, projected range, straggling of 12C ion in biological materials

‘The Stopping and Range of Ions in Matter’ SRIM program, utilizing the built-in compound directory has been used to compute Bragg curve, projected range, longitudinal, lateral straggle of 12C ion with energies of 1 − 150 MeV in biological matter: liquid water (benchmark) human blood, skin, thyroid, and spleen are assessed. Results show that in the studied biological media for higher energy beam i): noticeable modification are seen in Bragg peak, shift in peak-position; ii) maximum projected range: 595.2 μm suggests effective use of 12C ions for cancer tumor therapy, especially for superficial cancer tumors, without much damage to healthier cells; iii) longitudinal straggling ~ 22.6 μm, low lateral straggling ~ 4.7 μm suggests potential application of 12C ions in treating cancer tumor nearby critical organs, causing minimal damage in nearby normal tissues.

Effects of H+ ion bombardment on GaAs photocathode surface with Cs-O and Cs-F activation layers

To characterize the degree of damage to the GaAs photocathode surface caused by H+ ion back bombardment in the electron-bombarded complementary metal–oxide–semiconductor (EBCMOS), Stopping Range of Ions in Matter software based on the Monte Carlo method was used to investigate the effect of H+ ions with different incident energies on the surface of Cs-O (Cs-F) activated GaAs photocathode. During the simulations, different Cs/O (Cs/F) ratios ranging from 1:1 to 4:1 were considered. The sputtering rates, backscattering electrons, and longitudinal and lateral displacements along with vacancies/ions were investigated. According to the analysis of sputtering rates and vacancies, the optimal Cs/O ratio and Cs/F ratio are 3:1 and 4:1, respectively. With the increase in the incident energy, the backscattering rates decrease, the peak value of the H+ ion distribution decreases, while the corresponding peak position increases, and the peak value of the vacancy distribution increases first and then decreases, while the corresponding peak position increases. In addition, the projected ranges, and lateral and longitudinal displacements increase with the increase in incident energies, while the projected ranges may far exceed the straggle lengths and make the ion trajectory become more and more concentrated in the high incident energy region. This work helps to understand the degeneration mechanism of the GaAs photocathode operating in EBCMOS.

Strain-insensitive and multiplexed potentiometric ion sensors via printed PMMA molecular layer

Wearable biomimetic electronics have aroused tremendous attention due to their capability to continuously detect and deliver real-time dynamic physiological signals pertaining to the wearer's environment. However, upon close contact with the human skins, a wearable sensor undergoes mechanical strain which inevitably degrades the electrical performance. To address this issue, we demonstrate a universal design approach for stretchable and multiplexed biosensors that can yield unaltered ion sensing performance under variable mechanical tensile strains, which is achieved by introducing a PMMA molecular layer between stretchable substrate and ion sensors. Such design demonstrates reliable multiplexed ion sensing capability and provides high sensitivity (>50 mV/decade), reliable selectivity, as well as wide working range (0.1–100 mM) for sodium, ammonium, potassium and calcium ions in complex sweat biomarkers. Via this introduced PMMA molecular layer, our sensor even exhibits 95 % electrical performance maintained up to 30 % tensile strain, whereas the mechanical tensile property is far superior to original sensor performance. Besides, the sensors were also utilized for real-time monitoring of ions in sweat to validate its biomedical electronics applications. This sensing platform can be easily extended to other biomimetic sensors to enable stable signal acquisition for biomedical electronics.

New insights into temperature-induced mechanisms of copper adsorption enhancement on hydroxyapatite-in situ self-doped fluffy bread-like biochar

The utilization of kitchen bones as a renewable resource for biochar production holds significant promise. In this study, three distinct pig-bone-based biochars (PBCs) were synthesized at varying pyrolysis temperatures to investigate the influences of Hydroxyapatite (HAP) self-doped on crystal morphology, formation of functional active sites, and Cu2+ efficient adsorption. The results showed that low-temperature-induced alterations in HAP crystal morphology led to the formation of a highly active “fluffy bread-like” structure (FBS) in PBC-500, exhibiting exceptional Cu2+ adsorption capacity (71.60 mg·L−1) with an 86% adsorption achieved within 15 min. Notably, PBC-500 demonstrated a unit-specific surface area adsorption capacity for Cu2+, which was 1.52 and 1.19 times higher than the nano-wire-like PBC-700 and the nano-spherical-like PBC-900, respectively. Modern Spectroscopic analyses established the presence of a range of active centers (–OH, –CONH2, -PO43-) on PBC-500′s FBS carrier along with its highly efficient adsorption mechanism for Cu2+. These findings were strongly supported by electrostatic potentials and the frontier orbital theory of Quantum DFT methods, providing insights into the crucial chemical mechanisms by which active sites, such as phosphorus, nitrogen, and oxygen centers, enhance Cu2+ adsorption. Furthermore, PBC-500 exhibited superior adsorption binding energy and chemical reactivity, retaining high activity across a range of pH levels, inorganic ions, and organic matter. This study establishes empirical and theoretical foundations for the efficient utilization of kitchen pig bones as a sustainable resource and the eco-friendly synthesis of high-performance self-doped biochar, contributing to sustainable material innovation.

A novel sulfhydryl-modified superparamagnetic photonic crystal sensing material for the simultaneous heavy metal ions detection and adsorption treatment

A novel superparamagnetic photonic crystal (Fe3O4@SiO2@Sulfhydryl SPC) was successfully created for simultaneous visual detection and absorption of harmful heavy metal ions. This SPC was made by combining photonic crystal and superparamagnetic nanosphere technologies. During detection, Fe3O4@SiO2@Sulfhydryl nanospheres can move in the liquid sample and fully absorb the target substances. The detection range is from 1 μg/L to 5 mg/L, which corresponds to the critical concentration range for heavy metal ions in drinking water and sewage. The detection limit is 1 μg/L. In the detection process, the signal responded rapidly and remained stable when analyzed with a fiber optic spectrometer. Notably, the signal intensity decreased significantly, with a reduction of 62.22 a.u. for Hg2+ and 124.31 a.u. for Ag+. Simultaneously, the visual results were striking. The SPC changed color from orange (PC structural color) to the original reddish-brown color of the solution with the formation of magnetic aggregates (PC structural color disappeared). This SPC exhibits excellent sensitivity, offers a clear visual display, possesses strong absorption detection capabilities, is easy to use, cost-effective, and, importantly, does not cause secondary pollution. Furthermore, the harmful heavy metal ions absorbed by the SPC can be easily removed from the water sample using an external magnetic field, overcoming challenges related to efficient separation of the adsorbent material from wastewater. As a result, this SPC holds great promise for real-time visual monitoring and practical sewage purification processes.

Impact of swift heavy ion irradiation on as-grown gallium nitride epilayers by MOCVD technique

The as-grown GaN by Metalorganic Chemical Vapor Deposition was utilized to study the irradiation effects on GaN epilayers. The stopping range of ions in the matter is studied to choose the energy range for irradiation. The grown epilayers were irradiated with light and heavy ions of O7+ and Ag12+ by varying ion fluence. The X-ray Diffraction confirmed the wurtzite crystal structure for pristine and all the irradiated GaN epilayers. Atomic force microscopy showed high surface roughness for heavy ion irradiation when compared with light ion. Micro-Raman analysis was carried out through the Lorentz line fitting and calculated the carrier concentration and phonon lifetime. In light and heavy ion irradiation, the carrier concentration enhances with defect formations. X-ray Photoelectron Spectroscopy analysis showed that light ion irradiation caused oxygen bonding, while heavy ion irradiation led to the Ga–Ga bond shift, revealing film degradation.

Defect-specific strength factors and superposition model for predicting strengthening of ion irradiated Fe18Cr alloy

A high-purity binary alloy Fe18Cr was subjected to heavy-ion irradiation in order to provide improved understanding of the irradiation effect on radiation hardening associated with dislocation loop and network formation, α’ precipitation. The specimens were irradiated with 8 MeV Fe ions (∼2 μm ion range) to midrange doses of 0.37 and 3.7 dpa at 300, 350 and 450 °C using dose rates of ∼10−5–10−3 dpa/s. Nanoindentation testing was performed to extract the bulk equivalent hardness at low depth from these ion irradiated specimens. High-quality transmission electron microscopy (TEM) images were acquired by utilizing a flash electropolishing method on the Focused Ion Beam (FIB) prepared liftouts. An accurate calculation of the strength factor was provided based on detailed TEM characterization of the irradiated microstructures. A newly refined hardening superposition method was applied to combine the strengthening components from each microstructure. The good agreement between microstructure predicted strength and measured strength further demonstrated the fidelity to use hardening model to quantify the mechanical properties of ion irradiated materials.

Functionalized hydrogen-bonded organic superstructures via molecular self-assembly for enhanced uranium extraction

Effective uranium extraction from water is essential for the development of nuclear power industry and the protection of human health and environment. Nevertheless, it still remains challenging to realize efficient and cost-effective uranium extraction. Herein, a fast and simple method for the direct fabrication of novel functionalized hydrogen-bonded organic superstructures via molecular self-assembly is reported. The as-constructed flower-like superstructures (MCP-5) can allow the exposure of adsorption sites and facilitate the transport of uranyl ions, while synergism between amino and phosphate groups can realize selective uranium extraction. Consequently, MCP-5 possesses excellent uranium adsorption ability with a high saturated adsorption capacity of 950.52 mg g−1, high utilization rate of adsorption sites and adsorption equilibrium time of simply 5 min in uranium-spiked aqueous solution. Furthermore, MCP-5 offers selective uranium adsorption over a broad range of metal ions. The facile synthesis and low-cost raw materials make it have promising potential for uranium capture. Simultaneously, this study opens a design avenue of functionalized hydrogen-bonded organic material for efficient uranium extraction.

Pyrogallol-based dipodal optical probe as new smart analytical tool for sustainable detection of cobalt in biosystem

The present research focuses on the micro-level detection of cobalt ions in biological and environmental samples using a new probe. The probe is a multifunctional symmetrical dipodal molecule with two pyrogallol binding units attached to the malonate scaffold through a propylene spacer. It was synthesized and characterized by 1H NMR, 13C NMR, IR, electronic spectroscopy, and mass spectrometry. The molecule's binding, thermodynamic, and photophysical properties are also described. The designed probe demonstrates an excellent sensing ability for Co(II) based on the ESIPT “OFF-ON” fluorescence mechanism. The experiments explore the high selectivity of the ligand for cobalt sensing over a wide range of metal ions of biological and environmental importance. The fluorescence intensity shows a linear response to Co(II) in 5–100 μM concentration with a detection limit of 8.75 x 10−5 and a 2.65-fold enhancement in the intensity. These results establish its potential application as a fluorescence sensor. The probe is also employed as a colorimetric sensor for the qualitative determination of cobalt ions in DMSO solution. The interesting behavior of the probe motivated us further to study its coordination properties with divalent cobalt in solution. The pre-organized assembly with an appropriate cavity size favors the ligand for an efficient Co(II) encapsulation by coordinating through imine-Ns and aromatic ring-Os donors, giving high formation constants.

On the use of SRIM for calculating arc-dpa exposure

We propose two methods for evaluating athermal recombination corrected (arc) displacement damage parameters in ion irradiations employing the computer code SRIM (Stopping and Range of Ions in Matter). The first method consists of post-processing the detailed SRIM output for all simulated damage events and re-calculating according to the arc damage model. In the second method, an approximate empirical formula is devised which gives the average displacements in the arc damage model as a function of the corresponding quantity according to the standard Norgett–Robinson–Torrens model, which is readily obtained from SRIM.