Search Results (232)

High-energy X-ray diagnostic systems are crucial for understanding hotspot high-density area asymmetry, fuel mixing, and other phenomena in inertial confinement fusion. To meet the demand for hotspot electron temperature measurements, we developed a high-energy dual-channel Kirkpatrick–Baez microscope. This microscope is characterized by a dual high-energy response and high spatial resolution, enabling the observation of fine structures in high-density regions of a hotspot. Spectral drift was effectively mitigated by optimizing the grazing incidence angle, and the spatial and spectral domains were coupled through experimental alignment. Herein, we describe the optical design of the proposed microscope. Furthermore, we performed simulations and backlight imaging to validate the performance of the proposed system. The results show that the spatial resolution was better than 3 μm in the center and better than 6.5 μm in a field of view of 300 μm. The spectral response efficiencies at 11.4 and 17.48 keV were 7.41 × 10⁻⁸ and 5.77 × 10⁻⁸ sr, which deviate from the theoretical values by 3.01% and 6.79%, respectively. Full article

This study systematically investigates for the first time the effects of dual-site co-cultivation on spectral characteristics and trace element enrichment in marine-cultured Akoya pearls from Beihai, China. Akoya pearls were cultured over a one-year period, with the final 40-day stage designated as the terminal phase. During this period, two experimental groups of pearl oysters were established: Group Y remained in Beihai for continued local cultivation and harvest, while Group B was transferred to Weihai, Shandong Province, for terminal-stage farming under different thermal conditions. A series of comparative analyses were performed using Fourier-transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, Raman spectroscopy, X-ray fluorescence (XRF), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The FTIR results revealed distinct differences between the two groups in the distribution of amide and polysaccharide functional groups, particularly around 1643 cm⁻¹ and 1100 cm⁻¹. The UV-Vis spectra of Group B displayed characteristic absorption bands at 430 nm and 460 nm, associated with the organic matrix of the nacre. Raman spectroscopy further indicated a higher abundance of organic-related vibrational features in Group B. Additionally, both XRF and LA-ICP-MS analyses consistently showed significant differences in the concentrations and distributions of trace elements, particularly copper (Cu), cobalt (Co), and zinc (Zn). The findings demonstrate that the dual-site co-cultivation mode significantly impacts both the organic composition and trace element enrichment patterns in seawater Akoya pearls. This research provides valuable references for optimizing environmental parameters in pearl cultivation processes. Full article

In the present work, the influence of external X-ray radiation on the kinetics of multicharged ions in high-temperature plasma is investigated. A generalized diagnostic approach is proposed for the electron density and temperature measurements of photo-pumped plasma based on the relative intensity of the H-like ion resonance line and its dielectronic satellites. Based on detailed kinetic calculations performed for argon plasma, the conditions under which these techniques can be applied without modification to the photo-pumped plasma are determined, and the relative intensities of these lines are calculated for cases where the external influence significantly alters the kinetics of their excitation. The development of such diagnostic methods is of particular importance for the experiments with powerful X-ray free-electron lasers and thermonuclear laser plasma. Full article

The growing demands for highly functional biomedical implants necessitate introducing innovative and easy-to-apply surface functionalization techniques, especially when it comes to stainless steel substrates. This study investigated the co-deposition of chitosan and Cu-doped bioactive glass on AISI 316L steel surfaces, with the latter providing a matrix in which fine bioactive glass powders are distributed. Cu-doping into the matrix of bioactive glass was conducted to assess its influence on the bioactivity, antibacterial properties, and structural integrity of the coating. The microstructure, mechanical properties, phase composition, and surface roughness of coated specimens were investigated through a scanning electron microscope (SEM), X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma (ICP), contact angles, adhesion tensile tests, and laser profilometry analyses. Results of adhesion tests indicated that Cu addition did not have a major implication for the mechanical properties of the coating layers. Results also revealed that the Cu-doped bioactive glass featured a hydrophilic and a rather uneven surface, both being upsides for biomedical properties. The cytotoxicity and antibacterial assessments showed promising cell viability and antibacterial properties of the deposited coatings. Full article

Bone diseases lead to an increasing demand for implants to treat long bone defects and for load-bearing applications. Osteoporosis care and accidental injuries are major contributors to this rising need. Our research aims to demonstrate innovative material systems and methods for preparing implants that can be used in regenerative medicine. We hypothesize that by combining titanium alloys (Ti6Al4V) with hydroxyapatite (Hap), we can enhance biocompatibility and tribo-mechanical performance, which are critical for the longevity of Ti-based surgical implants. Additionally, we investigate the application of laser surface treatments to expose the underlying porosity, thereby enhancing cell transport and promoting cell growth. In this study, we investigate the effects of two fabrication techniques—Spark Plasma Sintering (SPS) and powder metallurgy (PM)—on the properties of laser-textured Ti64/Hap biocomposites. Our findings demonstrate that the selected processing route significantly influences the microstructure, tribological performance, and surface properties of these materials. An X-ray diffraction (XRD) analysis corroborates our results from incubation studies in simulated body fluids, highlighting the impact of phase transformations during sintering on the chemical properties of Ti-Hap composites. Additionally, while laser surface texturing was found to slightly increase the friction coefficient, it markedly enhanced the wear resistance, particularly for the PM and SPS Ti + 5%Hap composites. Full article

The “yellow-skinned” Nanhong agate represents a unique variety of Nanhong agate found in northeastern Yunnan, China, and it is highly valued for its distinctive yellow exterior and clear red–yellow interface. Owing to the limited research on this variety, the present study provides the first comprehensive analysis. Field surveys and various laboratory techniques—including polarizing microscopy, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectrometry, ultraviolet–visible (UV-VIS) absorption spectrometry, Raman spectroscopy, micro X-ray diffraction (µ-XRD) with Rietveld refinement, electron microprobe analysis (EPMA), and laser ablation–inductively coupled plasma mass spectrometry (LA-ICP-MS)—were utilized to investigate its gemological, microtextural, spectroscopic, and geochemical characteristics. Field surveys identified the occurrence states of the “yellow-skinned” Nanhong agate. The laboratory results indicate that the agate primarily consists of α-quartz, with minor amounts of moganite, goethite, and hematite. The coloring mechanism observed in this study is consistent with the findings of previous studies: the external yellow coloration is due to goethite, while the internal red hue is attributed to hematite. Its unique pseudo-granular silica (Type III) structure provides a foundational basis for the later formation of the “yellow-skinned” agate variety, and geochemical data reveal the distribution patterns of elements. Based on geological surveys and experimental data, the formation of the “yellow-skinned” Nanhong agate in northeastern Yunnan can be divided into two stages: first, hydrothermal fluids filled the vesicles in the Permian Emeishan Basalt Formation (P₂β), leading to the formation of primary Nanhong agate. Subsequently, the Type III primary agate underwent weathering, erosion, transport, and deposition in the red–brown sandy mudstone of the Lower Triassic Feixianguan Formation (T₁f). The sedimentary environment in the second stage facilitated the conversion of outer hematite into goethite, resulting in the distinct “yellow-skinned” appearance with a clear red–yellow boundary. Based on the occurrence and stratigraphic relations, this study constrains the formation age of the “yellow-skinned” Nanhong agate to approximately 261.6 Ma. Full article

The recovery of gold in metallurgical processes is significantly influenced by the presence of refractory minerals. This study investigates the mineralogical characteristics of refractory gold in the Pituca II ore deposit, with a focus on identifying the sulfide minerals that encapsulate gold particles and understanding their impact on gold recovery rates via cyanidation leaching. To establish a theoretical basis for optimizing gold recovery, a comprehensive suite of analytical techniques including electron microprobe analysis, petrographic analysis, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and X-ray diffraction was employed to characterize the ore’s composition and mineralogical properties. The primary ore minerals identified were pyrite, galena, chalcopyrite, and sphalerite, with hessite occurring as an accessory phase. Gold was observed as fine-grained particles (<40 µm), predominantly enclosed within pyrite and galena, contributing to its refractory nature. Cyanidation tests revealed a strong correlation between particle size and leaching efficiency: material ground to D₈₀ = 170 mesh (90 μm) achieved a recovery rate of 81.2%, compared to 72.2% for material at D₈₀ = 100 mesh (150 μm). These findings elucidate the mineralogical constraints on gold recovery and underscore the necessity of appropriate particle size reduction to enhance leaching performance. The study provides practical insights and targeted recommendations for pretreatment strategies, thereby contributing to more efficient exploitation of refractory gold ores in similar geological settings. Full article

The process of recycling lithium-ion batteries is drawing global attention due to a shortage of critical raw materials (CRMs), a sustainable and environmentally friendly approach that meets the needs of many industries. Characterization is an important step in the recycling of black mass resulting from the processing of a lithium-ion battery at the beginning and the end of the processes because of the complexity of the feed material and to evaluate the process. This research proposes a beneficiation flowchart for the further separation of graphite particles from metal oxides based on the characterization results by combining scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), laser-induced breakdown spectroscopy, laser scattering particle size distribution analysis, X-ray fluorescence (XRF), X-ray diffraction analysis (XRD), inductively coupled plasma–optical emission spectroscopy (ICP-OES), and thermogravimetry–differential thermal analysis (TG/DTA). Based on these characterization results, it is suggested that black mass with coarser particle size (0.2–1 mm) goes to the liberation process for beneficiation of the Al and Cu and black mass with a size range of 0.053–0.2 mm goes to the froth flotation for beneficiation of the Mn, Ni, Fe, and Co. Finally, a black mass with a size range of <0.053 mm goes through the froth flotation after the agglomeration process. Full article

Background: Lamivudine is widely used alone or in combination with other anti-HIV drugs in the infant to adolescent age groups of pediatric populations. Compounding of medications is frequently used for pediatric patients. However, many issues have been reported for the compounded formulation such as assay, stability, safety, and efficacy. Three-dimensional printing can overcome these issues. Objective: The aim of this study was to understand the effect of process and formulation variables on lamivudine printlets for pediatric populations using selective laser sintering. Methods: The Plackett–Burman screening design was used to prepare 12 formulations to study six variables, namely, laser scanning speed (130–150 °C), surface temperature (105–120 °C), chamber temperature (250–350 mm/s), sucrose (0–30%), hydroxypropyl methylcellulose (0–42%), and Kollidon^® CL-M (0–5%). The formulations were tested for dissolution, disintegration, hardness, assay, X-ray diffraction, differential scanning calorimetry, stability, and pharmacokinetics in Sprague Dawley rats. Results: The assay of the printlet formulations varied between 93.1 and 103.5% and the disintegration time was 2.8 ± 1.2 (F1) to 43.7 ± 2.7 (F10) s. Due to high surface temperatures, the unsintered powder in the printing chamber experienced significant changes in crystallinity. No statistical significance was observed between the pharmacokinetic parameters of the printlets and commercial tablets (p > 0.05). The maximum plasma concentration (C_max), time to reach maximum plasma concentration (T_max), and area under the curve (AUC) of the printlets and commercial tablets were 295.5 ± 33.0 and 305.0 ± 70.1 ng/mL, 0.5 ± 0.0 and 1.0 ± 0.8 h, and 1414.1 ± 174.0 and 1987.2 ± 700.5 ng.h/mL, respectively. Conclusions: In summary, fast-disintegrating and dissolving 3D printed lamivudine was found to be bioequivalent to commercial formulation of lamivudine. Thus, it is a viable method for dispensing personalized lamivudine printlets for pediatric populations. Full article

The Arthur River magnesite deposit is in the northwestern part of Tasmania, Australia, within the Arthur Metamorphic Complex. Physical, mineralogical, and chemical characteristics of the deposit were studied using geological drill core logging and analytical techniques (scanning electron microscopy, portable x-ray fluorescence, and laser ablation–inductively coupled plasma–mass spectrometry). The results document variations within the ore body, and three ore types have been identified for the potential production of an economic magnesite concentrate separated from associated gangue minerals (dolomite, quartz, and talc and iron bearing minerals such as pyrite and pyrrhotite). The ore types were identified based on a combination of physical, chemical, and mineralogical differences. Type 1 has a relatively high magnesium content and appears in drill core as hard white crystalline magnesite. Type 2 has relatively lower magnesium and higher iron contents than type 1 and occurs visibly as creamy-yellowish soft magnesite. Type 3 ore has the lowest magnesium and the highest iron content of the three ore types and is reddish brown in color. From the characterization studies, potential beneficiation routes for each ore type are suggested along with potential processing challenges. Examples of processing challenges include magnesium present in both magnesite and in dolomite, and the association of magnesite with quartz and talc results in a relatively high silica content. Full article

The narrow bandgap InN material, with exceptional physical properties, has recently gained considerable attention, encouraging many scientists/engineers to design infrared photodetectors, light-emitting diodes, laser diodes, solar cells, and high-power electronic devices. The InN/Sapphire samples of different film thicknesses that we have used in our methodical experimental and theoretical studies are grown by plasma-assisted molecular-beam epitaxy. Hall effect measurements on these samples have revealed high-electron-charge carrier concentration, η. The preparation of InN epifilms is quite sensitive to the growth temperature T, plasma power, N/In ratio, and pressure, P. Due to the reduced distance between N atoms at a higher P, one expects the N-flow kinetics, diffusion, surface components, and scattering rates to change in the growth chamber which might impact the quality of InN films. We believe that the ionized N, rather than molecular, or neutral species are responsible for controlling the growth of InN/Sapphire epifilms. Temperature- and power-dependent photoluminescence measurements are performed, validating the bandgap variation (~0.60–0.80 eV) of all the samples. High-resolution X-ray diffraction studies have indicated that the increase in growth temperature caused the perceived narrow peaks in the X-ray-rocking curves, leading to better-quality films with well-ordered crystalline structures. Careful simulations of the infrared reflectivity spectra provided values of η and mobility μ, in good accordance with the Hall measurements. Our first-order Raman scattering spectroscopy study has not only identified the accurate phonon values of InN samples but also revealed the low-frequency longitudinal optical phonon plasmon-coupled mode in excellent agreement with theoretical calculations. Full article

Rapid thermal annealing (RTA) has been widely used in semiconductor device processing. However, the rise time of RTA, limited to the millisecond (ms) range, is unsuitable for advanced nanometer-scale electronic devices. Using sub-energy bandgap (E_G) 532 nm ultra-fast 15 nanosecond (ns) pulsed laser annealing, a record-high dielectric constant (high-κ) of 67.8 and a capacitance density of 75 fF/μm² at −0.2 V were achieved in Ni/ZrO₂/TiN capacitors. According to heat source and diffusion equations, the surface temperature of TiN can reach as high as 870 °C at a laser energy density of 16.2 J/cm², effectively annealing the ZrO₂ material. These record-breaking results are enabled by a novel annealing method—the surface plasma effect generated on the TiN metal. This is because the 2.3 eV (532 nm) pulsed laser energy is significantly lower than the 5.0–5.8 eV energy bandgap (E_G) of ZrO₂, making it unabsorbable by the ZrO₂ dielectric. X-ray diffraction analysis reveals that the large κ value and capacitance density are attributed to the enhanced crystallinity of the cubic-phase ZrO₂, which is improved through laser annealing. This advancement is critical for monolithic three-dimensional device integration in the backend of advanced integrated circuits. Full article

Fersmite ([Ca,Ce,Na][Nb,Ta,Ti]₂[O,OH,F]₆) from the Mount Brussilof magnesite deposit, British Columbia, Canada occurs as accessory brittle, black, submetallic to vitreous lustre, acicular to platy crystals up to 2 cm long, developed in sparry dolomite, which lines cavities in sparry magnesite. Fersmite also occurs as smaller crystals (<3 mm) enclosed by dolomite, where it is commonly fractured or broken, formed during the final stage of dolomite crystallisation. Electron microprobe (WDS) major element data indicate that the grains confirmed to be fersmite by X-ray diffraction contain >50% Nb and are atypically Ta-poor. Fersmite contains significant U and Th (up to 4700 ppm and 6 wt.%, respectively) and therefore is a viable mineral for U-Pb geochronology. A series of laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) spot analyses and maps were collected on fersmite grains. Although the fersmite grains have considerable common Pb and have experienced Pb loss, the U-Pb spot data suggest growth or pervasive resetting at ca. 190 Ma. Some ⁴⁰Ar/³⁹Ar ages (two of four samples) are consistent with the ~190 Ma U-Pb date. Electron microprobe and LA-ICP-MS mapping indicate that the fersmite is middle to heavy rare earth element-rich. The ~190 Ma fersmite age estimate provides an approximate upper time constraint on the age of sparry magnesite mineralisation, sparry dolomitisation, and, indirectly, on the formation of MVT deposits in the Kicking Horse Rim area and possibly elsewhere in southeastern British Columbia. Full article

This study investigated the potential for efficient and resourceful utilization of phosphogypsum (PG) through the preparation of a High-volume Phosphogypsum Cement Stabilized Road Base (HPG-CSSB). The investigation analyzed the unconfined compressive strength (UCS), water stability, strength formation mechanism, microstructure, and pollutant curing mechanism of HPG-CSSB by laser diffraction methods (LD), X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and inductively coupled plasma-mass spectrometry (ICP-MS). The optimal mix ratio of HPG-CSSB was 4% cement, 1% CA2, 35% PG, and 60% graded crushed stone. The UCS reached 6.6 MPa, 9.3 MPa, and 11.3 MPa at 7, 28, and 60 d, respectively. The alkaline curing agent stimulated cement activity and accelerated the release of Ca²⁺ and SO₄²⁻ from the PG. This formed many C-S-H gels and ettringite (AFt). The curing agent converted Ca²⁺ to C-(A)-S-H gels due to high volcanic ash activity. The diverse hydration products strengthened HPG-CSSB. The HPG-CSSB exhibits favorable water stability, demonstrating a mere 7.6% reduction in strength following 28 d of immersion. The C-S-H gel and AFt generated in the system can carry out ion exchange and adsorption precipitation with F⁻ and PO₄³⁻ in PG, achieving the curing effect of toxic and hazardous substances. HPG-CSSB meets the Class A standard for integrated wastewater discharge. Full article

In this report, the nonlinear optical (NLO) properties of titanium dioxide nanoparticles (TiO₂ NPs) have been explored experimentally using femtosecond laser light along with the Z-scan approach. The synthesis of TiO₂ NPs was carried out in distilled water through nanosecond second harmonic Nd:YAG laser ablation. Characterization of the TiO₂ NPs colloids was conducted using UV-visible absorption spectroscopy, transmission electron microscopy (TEM), inductively coupled plasma (ICP), and energy-dispersive X-ray spectroscopy (EDX). The TEM analysis indicated that the size distribution and average particle size of the TiO₂ NPs varied from 8.3 nm to 19.1 nm, depending on the laser ablation duration. The third-order NLO properties of the synthesized TiO₂ NPs were examined at different excitation laser wavelengths and incident powers through both open- and closed-aperture Z-scan techniques, utilizing a laser pulse duration of 100 fs and a high repetition rate of 80 MHz. The nonlinear absorption (NLA) coefficient and nonlinear refractive (NLR) index of the TiO₂ NPs colloidal solutions were found to be influenced by the incident power, excitation wavelength, average size, and concentration of TiO₂ NPs. Maximum values of 4.93 × 10⁻⁹ cm/W for the NLA coefficient and 15.39 × 10⁻¹⁵ cm²/W for the NLR index were observed at an excitation wavelength of 800 nm, an incident power of 0.6 W, and an ablation time of 15 min. The optical limiting (OL) effects of the TiO₂ NPs solution at different ablation times were investigated and revealed to be concentration and average size dependent. An increase in concentration results in a more limiting effect. Full article