Heavy Ion Research Articles

One-Step Synthesis of N-Doped Graphene Quantum Dots via Plasma Contacting Liquid for Multiple Heavy Metal Ion Detection

One-Step Synthesis of N-Doped Graphene Quantum Dots via Plasma Contacting Liquid for Multiple Heavy Metal Ion Detection

Robot-assisted resection of exposed colon with TaTME after heavy ion radiotherapy for locally recurrent rectal cancer

Abstract Introduction Heavy ion radiotherapy has shown promising results in treating pelvic recurrence of rectal cancer. We report a case where a patient underwent robot-assisted low anterior resection with transanal mesorectal excision (TaTME) following heavy ion radiotherapy, owing to challenges associated with spacer placement. Case presentation A 54-year-old man was diagnosed with upper rectal cancer. He underwent robot-assisted low anterior resection. Eight courses of CapeOX were administered as postoperative adjuvant chemotherapy. Immediately after completion of adjuvant chemotherapy (8 months postoperatively), computer tomography (CT) scan revealed a 30-mm large nodule on the dorsal surface of the oral anastomotic intestine, which was detected by PET-CT. Given that the tumor had an indistinct border with the sacrum and its superior margin extended to the second sacrum, it was concluded that a combined sacral resection was not advisable, and heavy ion radiotherapy was indicated. Robot-assisted low anterior resection combined with TaTME was performed approximately 2 months after heavy particle radiotherapy (73.6 Gy (RBE)/16 sessions). CT scan conducted 3 months after irradiation revealed substantial shrinkage of the recurrent tumor. Conclusions Robot-assisted resection of exposed colon with TaTME after heavy ion radiotherapy is regarded as an effective strategy for treating locally recurrent rectal cancer.

A Study of Ionospheric Heavy Ions in the Terrestrial Magnetotail Using ARTEMIS

AbstractIonospheric heavy ions in the distant tail of the Earth's magnetosphere at lunar distances are observed using the ARTEMIS mission. These heavy ions are originally produced in the terrestrial ionosphere. Using the ElectroStatic Analyzers (ESA) onboard the two probes orbiting the Moon, these heavy ions are observed as cold populations with distinct energies higher than the baseline energy of protons, with the energy‐per‐charge values for the heavy populations highly correlated with the proton energies. We conducted a full solar cycle survey of these heavy ion observations, including the flux, location, and drift energy, as well as the correlations with the solar wind and geomagnetic indices. The likelihood of finding these heavy ions in the preferred regions of observation called “loaded” quadrants of the terrestrial magnetotail is ∼90%, regardless of the z orientation of the IMF. We characterize the ratio of the heavy ion energy to the proton energy, as well as the velocity ratio of these two populations, for events from 2010 to mid‐2023. This study shows that the “common velocity” assumption for the proton and heavy ion particles, as suggested in previous work through the velocity filter effect, is not necessarily valid in this case. Challenges in the identification of the mass of the heavy ions due to the ESA's lack of ion composition discrimination are addressed. It is proposed that at the lunar distances the heavy ion population mainly consists of atomic oxygen ions (O+) with velocities ∼25% more than the velocity of the co‐located proton population.

One stone, two birds: An eco-friendly aerogel based on waste pomelo peel cellulose for the efficient adsorption of dyes and heavy metal ions

To achieve the objective of “waste control by waste”, in this study, a green aerogel adsorbent comprised of pomelo-peel cellulose and sodium alginate (PCC/SA) was prepared through dual-network crosslinking. The resulting 3D hierarchical porous structured PCC/SA aerogel exhibited good structural stability, and kept the morphological integrity during 10 days in a wide pH range (2–10), suggesting its potential for recycling in diverse complex environments. Besides, the superior adsorption capacities for methylene blue (MB) and Cu(II) were observed, with the qm values and adsorption equilibrium times were recorded to be 1299.59 mg/g (300 min) and 287.55 mg/g (120 min), correspondingly. Furthermore, the favorable reusability of the PCC/SA aerogel was also demonstrated, with the removal efficiency for MB remaining almost unchanged (about 94 %) after 10 adsorption-desorption cycles, while there was a slight reduction for Cu(II) from 85.28 % to 72.47 %. XPS and FTIR analysis revealed that electrostatic attraction, hydrogen bonding, cation exchange and coordination were the major adsorption mechanisms. Importantly, the PCC/SA aerogel can be naturally degraded in soil within 10 weeks. Therefore, the as-prepared aerogel bead derived from pomelo peel shows great promise as an adsorbent for wastewater treatment containing dye and heavy metal ions.

Feasibility of using optical Cherenkov radiation for non-relativistic ion beam diagnostics

In this paper, we propose to use quasi-monochromatic Cherenkov spectral lines for ion beam diagnostics. As representatives of light and heavy ions, we use C12 and Au197 ions, respectively. First, using the Geant4 toolkit, we determine the ionization lost energy as a function of the radiator penetration depth. After that, we use those data in the polarization currents method to compare the theoretical spectral lines with and without ionization losses. We also use the real-beam polarization currents method to analyze real-beam and setup parameters affecting the accuracy of the beam diagnostics. We emphasize that the precision of refractive index measurement might be a source of inaccuracy in ion beam diagnostics. Nevertheless, according to the provided data, we can expect that the method for measuring Cherenkov quasi-monochromatic spectral lines should be applicable for beam-diagnostics purposes, especially for lighter ions.

A Multifunctional Magnetic Fluorescent Nanoprobe for Copper(II) Using ZnS-DL-Mercaptosuccinic Acid-Modified Fe3O4 Nanocomposites

Cu2+ has increasingly become a great threat to the natural environment and human health due to its abundant content and wide application in various industries. DL-Mercaptosuccinic acid and ZnS-modified Fe3O4 nanocomposites were designed, synthesized, and applied in the determination of Cu2+. The prepared nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopes (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and thermogravimetric analyzer (TG). The magnetic fluorescent nanoprobe exhibited highly selective and sensitive fluorescence-quenching characteristics with Cu2+ ions. The fluorescence detection linear range was 0–400 μM, with the detection limit being 0.489 μM. In addition, the magnetic fluorescent nanoprobe exhibited a high adsorption and removal rate for Cu2+. It had been successfully applied to detect Cu2+ in real water samples with a satisfactory recovery rate. The magnetic fluorescent nanoprobe could simultaneously realize the functions of enrichment, quantitative detection, and separation, reduce the pollution of copper ions and probes, and establish an environment-friendly detection method. Consequently, the magnetic fluorescent nanoprobe offered a new pathway for the removal and detection of not only Cu2+ but also other heavy metal ions in water.

Mesoporous Au-CuO substrate with dual super-hydrophilicity and efficient chemical enhancement for 4-aminothiophenol SERS detection

aminothiophenol (4-ATP) residues and accumulation in aquaculture/animal husbandry are becoming a serious threat to food safety. Development of highly sensitive metal-semiconductor surface-enhanced Raman scattering (SERS) substrates for the detection of 4-ATP is urgently needed. In this work, mesoporous Au-CuO substrate with dual super-hydrophilicity and efficient chemical enhancement is constructed for high-sensitivity SERS detection of 4-ATP. Mesoporous Au-CuO substrate is prepared by thermal decomposition. The super-hydrophilic substrate could mitigate droplet-induced "coffee ring" effect, thereby promoting rapid diffusion and uniform distribution of target molecules. Meanwhile, hybridizing gold nanoparticles (Au NPs) and CuO could enhance analyte polarization rate in that multi-channel photon-induced charge transfer between the target molecule and Au-CuO substrate. Mesoporous Au-CuO exhibited high sensitivity (10-8M) and reproducibility (Relative standard deviation (RSD=6.06%, n=11)) for crystal violet (CV) probe. The as-prepared substrate demonstrated reliable assay ability for 4-ATP with a detection limit of 10-7M and a good reproducibility with RSD=3.33% (n=11). Additionally, the substrate was not impacted by heavy metal ions in actual water environment. Trace residues of 4-ATP were still detected at concentrations as low as 10-7M. Au-CuO substrate is expected to be a favorable candidate for the detection of 4-ATP residues in complex matrices.

Acetate anions intercalated Fe/Mg-layered double hydroxides modified biochar for efficient adsorption of anionic and cationic heavy metal ions from polluted water

Acetate anions intercalated Fe/Mg-layered double hydroxides modified biochar for efficient adsorption of anionic and cationic heavy metal ions from polluted water

Mussel-inspired polydopamine and Zr-porphyrin MOF co-decoration of a cellulose paper-based composite membrane for efficient photoreduction of Cr(VI) and photothermal antibacterial in wastewater

Abundant hazardous pollutants, in particular heavy metal ions and microbes, in aqueous systems seriously threaten ecological safety and human health. Photocatalysis is deemed an appealing solution yet remains challenging to exploit more efficient, economical, and sustainable photocatalytic materials. In this study, we successfully fabricated a cellulose paper-based composite membrane, namely Zr-TCPP@PDA@FP, for photoreduction of Cr(VI) and photothermal antimicrobial. For the resultant composite membrane, the self-polymerization polydopamine (PDA)-coated cellulose fibers act as sustainable scaffolds to anchor the in-situ synthesized porphyrin-doped UiO-66-NH2 (Zr-TCPP) nano-photocatalysts. The hypotheses are that: 1) porphyrin doping in Zr-TCPP can both reinforce the visible-light absorption and the transport of photogenerated electrons; 2) mussel-inspired PDA coating on fiber surface not only services as binder to promote the Zr-TCPP loading and dispersion, but also functions as heterojunction interface to accelerate photogenerated electron separation and transfer from Zr-TCPP; As a result, Zr-TCPP@PDA@FP exhibited significant photocatalytic reduction towards Cr(VI), achieving a removal efficiency of 93.9 % within 20 mins and cycling stability. Besides, the hybrid membrane also featured excellent photothermal antibacterial performance (over 99 % for both E. coli and S. aureus). This work will inspire the development of economic and sustainable cellulose-based functional materials for efficient wastewater remediation.

Radial and Tangential Friction Coefficients: Derivation of Formulas, Calculation and Application in Modeling of the Heavy Ion Collision Process

Radial and Tangential Friction Coefficients: Derivation of Formulas, Calculation and Application in Modeling of the Heavy Ion Collision Process

Monte Carlo Simulations of the Interaction of 55Mn with 14.7-MeV Protons Produced by D+3He Fusion Reaction

The global energy crisis and climate change pose significant challenges for the future of humankind. To address these issues, clean energy sources are being promoted, with nuclear energy being an effective solution. The development of fission reactors and the promising advancements in fusion reactor technology provide potential solutions. However, challenges related to security and costs remain. This study focuses on the interaction between 55Mn and protons at 14.7 MeV using Monte Carlo simulations. Various Monte Carlo codes, including TALYS-1.96, GEANT4 (for GEometry ANd Tracking), PHITS-3.31 (for Particle and Heavy Ion Transport Code System), SRIM-2013 (for Stopping and Range of Ions in Matter), and ATIMA v1 41 (for ATomic Interaction with MAtter), were employed to investigate different interaction mechanisms. The research aims to understand the impact of these interactions on reactor performance, particularly in the context of the fusion facility. Manganese-containing steels play a crucial role in enhancing efficiency, durability, and safety in fusion reactors. The findings contribute to ongoing research and development activities in the field of nuclear energy.

Development of a non-intercepting weak beam current measurement electronics for Heavy Ion Accelerator Facility in Lanzhou.

Non-destructive measurements of low-intensity charged particle beams are particularly challenging for beam diagnostics. At the Heavy Ion Accelerator Facility in Lanzhou (HIRFL), beams with weak currents below 1 µA are often provided for experiments. The detection of such low beam current is below the threshold of typical standard beam current transformers. Therefore, a low-intensity monitoring system is developed by using a sensitive capacitive pick-up (PU) and low-noise electronics. This device measures beam currents by digitally analyzing the amplitude of the PU signals using a homodyne detection scheme. During lab tests, the amplitude nonlinearity is <0.5% in the operational range of 1 nA-45 µA and the amplitude resolution is 0.94 nA. At present, four measurement systems for low beam currents are installed at HIRFL for the monitoring of standard operating conditions with low beam currents below 1 µA. After an absolute calibration with a Faraday cup, it can be used for accurate beam intensity measurement with a current resolution of about 1 nA.

Plasmon Excitation in the Interaction of Slow Singly Charged Argon Ions with Magnesium

We report angle-resolved energy spectra of electron emitted in the interaction of slow singly charged heavy ions with Mg surface. The work is focused mainly on the excitation of plasmons of Mg under Argon impact. Potential excitation of plasmons occurs when incoming ions are neutralized at the expense of the potential energy carried by incoming ions. The process competes with the known mechanisms of neutralization via Auger transitions. Differently from Al samples, our results show that the neutralization of Ar+ ions at Mg is dominated by the excitation of surface plasmons by the potential energy released in the electron capture process that neutralizes incoming ions. Bulk plasmon excitation is observed at higher impact energy and is ascribed to fast electrons excited by the transfer of the kinetic energy of incoming particles. The data show that bulk plasmon excitation occur inside the bulk, while the theoretically predicted excitation by potential energy transfer of incoming projectiles is not observed.

The hazardous protective glass material for gamma, neutrons, and behaviors of charged particles: Results of adding barium oxide concentrations

The objective of this research is to examine the effectiveness of gamma and neutron shielding, as well as to investigate the behavior of charged particles in glass compositions with the formula xBaO:5SnO2:10Na2O:10CaO:10Li2O: (65-x)SiO2. These glass compositions will be created using the melt quenching technique (MQT). The findings indicated that the physical characteristics, such as density and molar volume, exhibited a comparable pattern. The gamma-ray shielding capacity of the glass system was assessed by comparing it with theoretical, simulation, and experimental values obtained using WinXCom, PHITS (Particle and Heavy Ion Transport Code System) Monte Carlo simulation, and Compton scattering technique (CST), respectively. The results revealed that the total attenuation (μm), effective atomic number (Zeff), and electron density (Nel) exhibited a consistent increase with higher BaO contents. Additionally, this increase led to a decrease in scattering energy within the Compton energy range. The half-value layer (HVL) exhibited superior shielding characteristics compared to alternative substances. Furthermore, the addition of more BaO atoms in the glass structure results in an increased ability of the material to stop the motion of charged particles with larger mass. Conversely, lower concentrations of BaO demonstrate an efficient barrier against fast neutrons. The simulation revealed that BaO can be utilized as an additive in glass materials to enhance their radiation shielding properties in environments with high levels of radiation.

Charmonium Transport in Heavy-Ion Collisions at the LHC

Charmonium Transport in Heavy-Ion Collisions at the LHC

Low energy alpha particles dose mapping with a combination of CR-39 detector and a high resolution flatbed scanner

The potential of a combination of the well-known CR-39 detector and a high-resolution flatbed scanner for low energy alpha particles dose mapping is investigated. The CR-39 detectors were irradiated with perpendicular incident 4 MeV alpha particles of doses 0.009, 0.018, 0.033, 0.051, 0.067, 0.134, and 0.164 Gy, thereafter, etched in 6.25 N NaOH at 70 °C. The CR-39 detectors were scanned with Canon CanScan 9000F Mark II of spatial resolution of 9600 dpi and color depth of 48 bit. The measurements reveal that the pixel values for different color channels are correlated linearly with 4 MeV alpha particles dose at the etching times of 2 h, 3 h, and 4 h. For blue channel, the maximum sensitivity was −53178 ± 1463 pixel value/Gy at etching time of 4 h, compared to −15290 ± 2004 pixel value/Gy, and −42255 ± 840 pixel value/Gy at 2 h and 3 h respectively, the negative sign indicates the pixel values decrease as the 4 MeV alpha particles dose increases. While for etching times, 5 h and 6 h, the pixel values decrease exponentially as the 4 MeV alpha particles dose increases. For prolonged etching time, the pixel values are non-monotonic function of alpha particles dose. The optical density was evaluated as a function of etching time (removal thickness) of CR-39 irradiated with different doses. For 0.009 Gy, and 0.018 Gy doses of alpha particles, the optical density is linearly correlated with the etching time; for other doses, the optical density is not a monotonic function of the etching time. These new findings pave the way to use the combination of the CR-39 detector and high-resolution flatbed scanner for dose mapping of alpha particles and heavy ions over large-scale areas, applying etching conditions for each particle type and corresponding energy, that produce maximum sensitivity and linearity.

Flexible cellulose nanofiber aerogel with enhanced porous structure and its applications in copper(II) removal

In order to achieve an aerogel with both rigid pore structures and desired flexibility, stiff carboxyl-functionalized cellulose nanofiber (CNFs) were introduced into a flexible polyvinyl alcohol-polyethyleneimine (PVA-PEI) crosslinking network, with 4-formylphenylboronic acid (4FPBA) bridging within the PVA-PEI network to enable dynamic boroxine and imine bond formation. The strong covalent bonds and hydrogen connections between CNF and the crosslinking network enhanced the wet stability of the aerogel while also contributed to its thermal stability. Importantly, the harmonious coordination between the stiff CNF and the flexible polymer chains not only facilitated aerogel flexibility but also enhanced its increased specific surface area by improving pore structure. Moreover, the inclusion of CNF enhanced the adsorption capacity of the aerogel, rendering it effective for removing heavy metal ions. The specific surface area and adsorption capacity for copper ions of the aerogel increased significantly with a 3 wt% addition CNF suspension, reaching 19.74 m2 g−1 and 60.28 mg g−1, respectively. These values represent a remarkable increase of 590.21 % and 213.96 %, respectively, compared to the blank aerogel. The CNF-enhanced aerogel in this study, characterized by its well-defined pore structures, and desired flexibility, demonstrates versatile applicability across multiple domains, including environmental protection, thermal insulation, electrode fabrication, and beyond.

Development of a composite MoS2/PEI nanofiltration membrane for radionuclides efficient removal from aquatic environments

The simultaneously efficient removal of radionuclides and heavy metals is an important and challenging topic for aquatic environmental protection. In this work, molybdenum disulfide (MoS2) with heavy metal ion adsorption capacity and positively charged polyethyleneimine (PEI) were used to fabricate a novel layer-by-layer (LbL) self-assembly composite membrane by a simple alternating immersion method. The unique structure with positive charge ensures high removal for toxic metals (RCs(I) = 99.83 %, RSr(II) = 100 %, RHg(II) = 99.2 %, RPb(II) = 98.13 %, RAs(III) = 98.5 %). The inherent low resistance channels in MoS2 provided the optimized composite membrane an elevated water flux. Long-term experiments and membrane regeneration also demonstrated that the membrane possesses exceptional stability and reusability in removing low levels of radionuclides Cs(I) and Sr(II) from water. This study confirms the feasibility of the MoS2-PEI composite membrane for the treatment of contaminated waters containing radionuclides and heavy metals.

Metal-organic framework membrane-based probe for on-site and sensitive detection of Cr(VI) in groundwater using a portable system

Groundwater sources are often contaminated by heavy metal ions such as hexavalent chromium (Cr(VI)) produced by various industrial processes, which can accumulate in the human tissues through drinking of water, resulting in serious health hazards. For this reason, on-site and sensitive detection of heavy metals in contaminated groundwater is essential for effective heavy metal pollution evaluation. Here, we develop a carboxymethyl cellulose (CMC)-metal–organic framework (MOF) fluorescence sensing membrane and couple with portable laser-induced fluorescence spectrometers (LIFs) for on-site detection of trace Cr(VI) in groundwater. The membrane was prepared using coordination assembly approach between flexible CMC and MOF and subsequent vacuum-assisted filtration. The CMC-MOF membrane exhibits very sensitive behaviour to Cr(VI) with a detection limit as low as 3.72 ppb, lower than the World Health Organization defined action level (50 ppb). Density functional theory calculations show that the formation of coordination bonds between CMC and MOF results in the excellent stability of the CMC-MOF membrane, and Cr(VI) simultaneously binds to two nitrogen atoms in MOFs, enabling CMC-MOF membrane to enrich and be on-site detection of trace Cr(VI) in contaminated groundwater by portable LIFs. This work provides an approach for on-site and highly sensitive assessment of heavy metal in contaminated groundwater.

Genome-wide identification of heavy-metal ATPases genes in Areca catechu: investigating their functionality under heavy metal exposure

Heavy-metal ATPases (HMAs) play a vital role in plants, helping to transport heavy metal ions across cell membranes.However, insufficient data exists concerning HMAs genes within the Arecaceae family.In this study, 12 AcHMA genes were identified within the genome of Areca catechu, grouped into two main clusters based on their phylogenetic relationships.Genomic distribution analysis reveals that the AcHMA genes were unevenly distributed across six chromosomes. We further analyzed their physicochemical properties, collinearity, and gene structure.Furthermore, RNA-seq data analysis exhibited varied expressions in different tissues of A. catechu and found that AcHMA1, AcHMA2, and AcHMA7 were highly expressed in roots, leaves, pericarp, and male/female flowers. A total of six AcHMA candidate genes were selected based on gene expression patterns, and their expression in the roots and leaves was determined using RT-qPCR under heavy metal stress. Results showed that the expression levels of AcHMA1 and AcHMA3 genes were significantly up-regulated under Cd2 + and Zn2 + stress. Similarly, in response to Cu2+, the AcHMA5 and AcHMA8 revealed the highest expression in roots and leaves, respectively. In conclusion, this study will offer a foundation for exploring the role of the HMAs gene family in dealing with heavy metal stress conditions in A. catechu.