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Line intensity ratios (LIRs) of helium (He) atoms are known to depend on electron density, n e , and temperature, T e , and thus are widely utilized to evaluate these parameters, known as the H e I LIR method. In this conventional method, the measured LIRs are compared with theoretical values calculated using a collisional-radiative (CR) model to find the best possible n e and T e . Basic CR models have been improved to take into account several effects. For instance, radiation trapping can occur to a significant degree in weakly ionized plasmas, leading to major alterations of LIRs. This effect has been included with optical escape factors in CR models. A new approach to the evaluation of n e and T e from He I LIRs has recently been explored using machine learning (ML). In the ML-aided LIR method, a predictive model is developed with training data, which consists of an input (measured LIRs) and a desired/known output (measured n e or T e from other diagnostics). It has been demonstrated that this new method predicts n e and T e better than using the conventional method coupled with a CR model, not only for He but also for other species. This review focuses mainly on low-temperature plasmas with T e ⩽ 10 eV in linear plasma devices. [ABSTRACT FROM AUTHOR]

Atmospheric pressure plasma jets (APPJs) have attracted significant attention due to their ability to generate plasma without vacuum systems, facilitating their use in small areas of plasma processing applications across various fields, including medicine, surface treatment, and agriculture. In this study, we investigate the interaction between two helium plasma jets, focusing on the effects of varying flow rate, voltage, and directional angle. By examining both in-phase and out-of-phase configurations, this research aims to elucidate the fundamental mechanisms of plasma plume merging, which has critical implications for optimizing plasma-based material processing systems. We demonstrate that while increasing voltage and flow rate for the in-phase condition leads to an extended plasma plume length, the plumes do not merge, maintaining a minimal gap. Conversely, plasma plume merging is observed for the out-of-phase condition, facilitated by forming a channel between the jets. This study further explores the impact of these merging phenomena on plasma chemistry through optical emission spectroscopy, revealing substantial differences in the emission intensities of OH, the second positive system of N 2 , and the first negative system of N 2 + . These findings offer valuable insights into controlling plasma jet interactions for enhanced efficiency in plasma-assisted processes, particularly where plume merging can be leveraged to improve the treatment area and intensity. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp), a biocompatible ceramic material, has been the priority source in several biomedical applications due to its bone type composition, crystallography and morphology. In the current research, firstly, HAp powder was synthesized from the waste eggshells using a modified synthesis route, i.e., multistage calcination preceded by a chemical precipitation method for process optimization. Secondly, the silver-doped HAp was synthesized with varying weight percent (0.0, 0.1, 0.2 and 0.5 wt.%) of silver nitrate (AgNO3) in HAp. An increase of 5.52% and 23.68% in maximum compressive strength and Vickers microhardness was observed between the undoped and 0.2 wt.% silver-doped HAp, showing the improved adhesion and bonding strength of the sintered samples. The porosity percentage also decreased with an increase in silver doping and was minimum for HAP0.2Ag (7.969%). The flowability characteristics demonstrate good flow for HAP0.0Ag (HR = 1.175 and CI = 14.89) and HAP0.1Ag (HR = 1.174 and CI = 14.87), and persists the travelable flow up to 0.5 wt.% (angle of repose = 42 ± 1.28, n = 3). Silver doping exhibits a synergistic effect, yielding satisfactory physiomechanical and antibacterial properties up to 0.2 wt.%. Inductively Coupled Plasma Mass Spectroscopy, x-ray Diffraction Technique, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, and Energy-Dispersive Spectroscopy verify the morphology, chemical composition, bonding strength, crystallite size, particle size, lattice strain and phase purity, respectively. Six different bacteria strains, i.e., S. epidermidis, S. aureus, B. subtilis, E. coli DH5α, P. aeruginosa and E. coli, employed for antibacterial characterization confirm the antibacterial nature of silver-doped HAp. Results obtained accentuate the antibacterial nature of silver-doped HAp and its utility in biomedical applications. [ABSTRACT FROM AUTHOR]

The doping process is a unique method of changing the microstructure of a material, influencing its mechanical, thermal, and optical properties. Typically, the doping process is carried out via chemical reagents. In this work, we present a "green" method of doping photochromic TiO2 via low-temperature plasma. The doping agent was the electrode material that was sputtered during plasma burning. The process of electrode sputtering is confirmed by the emission spectroscopy data of the plasma zone and the mass loss of the electrodes. The doping process was confirmed by X-ray, Raman spectroscopy, and XPS analyses. The role of the dopant nature and the action of diaphragm discharge in improving the photochromic properties of titanium dioxide is considered. [ABSTRACT FROM AUTHOR]

We demonstrate a genuine method for three-dimensional pictorial reconstructions of two-dimensional, three-dimensional, and hybrid specimens based on confocal Raman data collected in a back-scattering geometry of a 532-nm setup. The protocol, or the titular PRISM (Phase-Resolved Imaging Spectroscopic Method), allows for sub-diffractive and material-resolved imaging of the object's constituent material phases. The spacial component comes through either the signal distal attenuation ratio (direct mode) or subtle light-matter interactions, including interference enhancement and light absorption (indirect mode). The phase component is brought about by scrutinizing only selected Raman-active modes. We illustrate the PRISM approach in common real-life examples, including photolithographically structured amorphous Al2O3, reactive-ion-etched homoepitaxial SiC, and Chemical Vapor Deposition graphene transferred from copper foil onto a Si substrate and AlGaN microcolumns. The method is implementable in widespread Raman apparatus and offers a leap in the quality of materials imaging. The lateral resolution of PRISM is stage-limited by step motors to 100 nm. At the same time, the vertical accuracy is estimated at a nanometer scale due to the sensitivity of one of the applied phenomena (interference enhancement) to the physical property of the material (layer thickness). [ABSTRACT FROM AUTHOR]

ABSTRACT This study investigated the relation between the solubility and floatability of the soluble mineral brucite, focusing on the concentration characteristics of dissolved Mg2+ in brucite under three dissolution methods and the surface characteristics after dissolution. Some common rules of brucite flotation in three anionic collectors were discovered. Results of a flotation test showed that for three anionic collector systems of sodium oleate, sodium dodecyl sulfonate, and oxidized paraffin soap, the flotation recovery rate of brucite increased with the time of dissolution and decreased with the removal of dissolved Mg2+, but the flotation recovery rate is lower than that of untreated brucite. Inductively coupled plasma spectroscopy indicated that the content of dissolved Mg2+ in brucite slurry increases with increasing brucite content or dissolution time. Zeta potential measurements showed that the ability of dissolved Mg2+ to increase the surface potential of brucite follows the order of H2SO4 action > HCl action > H2O action. Adsorption capacity measurements showed that the presence of dissolved Mg2+ after dissolution is not beneficial for the adsorption of the three collectors on the surface of brucite. The capacity of the adsorption collectors follows the order of brucite after H2O dissolution > brucite after HCl dissolution > brucite after H2SO4 dissolution. Scanning electron microscopy and X‐ray photoelectron spectroscopy analyses indicated that the surface dissolution promoted the dissolution of Mg2+ on brucite surface in the solution, reducing the number of Mg sites on brucite surface and deteriorating the collection effect of the collector. [ABSTRACT FROM AUTHOR]

A new method is proposed for measuring the electron plasma temperature at the GOL-NB facility. The method is based on measuring the ratio between the intensities of the spectral lines emitted by the fast atoms injected into the plasma. The beams of fast hydrogen atoms used for heating the plasma at the GOL-NB facility contain not only atoms with a full energy (E) but also atoms with fractional energies (E/2, E/3, E/18) that appear as a result of the dissociation of the H , H , and H2O+ molecular ions. The spectral lines of the beam components with these energies (and, in particular, the hydrogen Hα line) can be resolved due to the Doppler shift caused by the difference between the atom speeds. For atoms with low energy, the excitation that leads to the photon emission occurs only due to their collisions with thermal electrons, while for atoms with high energy, a sufficient deposition into their excitation is given by their collisions with the plasma ions. This is why the ratio between the intensities of the lines of different beam components depends on the plasma electron temperature, and thus, it can be used to measure this temperature. At the beam energy of 24 keV, the proposed method can be used to measure the electron temperature in the range of up to 40 eV, which is of interest for the current experiments conducted at the GOL-NB facility. Note that measurement of the electron temperature higher than 20 eV requires that the ratio between the spectral line intensities be measured with an accuracy of the order of one percent, and that the attenuation of the neutral beam that passes through the plasma be measured with the same accuracy. The proposed method can be used at other fusion facilities that use fast hydrogen atom injection to measure the temperature of the edge plasma. [ABSTRACT FROM AUTHOR]

Coenurosis is a parasitic disease caused by the larval stage of Taenia multiceps, Coenurus cerebralis, typically found in the central nervous system of different livestock such as sheep and goats. The blood plasma from fifteen clinically healthy sheep and six sheep with neurological symptoms was studied by fluorescence spectroscopy in order to establish the contribution of kynurenic acid (KYNA), the neuroprotective metabolite of the kynurenine pathway, to the total fluorescence of the plasma. CT scans were used to confirm the presence of cysts in the central nervous system of sheep with neurological symptoms. The fluorescence spectroscopy analysis and further spectra deconvolution process revealed some significantly lower KYNA contributions to the total plasma fluorescence in sheep with coenurosis compared to healthy controls. Our results indicate that KYNA emission parameters could serve as valuable diagnostic markers, particularly for detecting preclinical cases of coenurosis, thus allowing for improved farm management practices. [ABSTRACT FROM AUTHOR]

The application possibilities of austenitic stainless steels in high friction, abrasion, and sliding wear conditions are limited by their inadequate hardness and tribological characteristics. In order to improve these properties, the thermochemical treatment of their surface by plasma nitriding is suitable. This article is focused on the corrosion resistance of conventionally plasma-nitrided AISI 304 stainless steel (530 °C, 24 h) in 0.05 M and 0.5 M sodium chloride solutions at room temperature (20 ± 3 °C), tested by potentiodynamic polarization and electrochemical impedance spectroscopy. Optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy are used for nitrided layer characterization. The experiment results confirmed the plasma-nitrided layer formation of increased micro-hardness related to the presence of Cr2N chromium nitrides and higher surface roughness compared to the as-received state. Both of the performed independent electrochemical corrosion tests point to a significant reduction in corrosion resistance after the performed plasma nitriding, even in a solution with a very low chloride concentration (0.05 mol/L). [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of the electrochemical and anticorrosion properties of leaded α,β'-brass (CuZn39Pb3), both in its bare form and coated with an octadecanethiol self-assembled monolayer (ODT SAM). The study was conducted in a non-complexing ClO4– solution at pH3, with and without halide ions. The results demonstrate that CuZn39Pb3 exhibits good resistance to dissolution compared to lead-free diphasic brass (Cu40Zn). It is observed that the exposure time to the corrosive solution and the concentration of different halide species strongly influence the dissolution of CuZn39Pb3. The formation of ODT SAMs on CuZn39Pb3 was characterized using various techniques, and optimal conditions to obtain a compact monolayer were determined. The data show that ODT SAMs effectively suppress the selective dissolution of CuZn39Pb3 alloy. Both Tafel polarization curves and electrochemical impedance spectroscopy (EIS) results are in good agreement and demonstrate the high ability of ODT SAMs to protect the alloy against corrosion, even in the presence of halide species. Under our conditions, the ODT film primarily acts as a cathodic inhibitor and behaves as a mixed inhibitor type. Notably, F‾ ions have a minimal effect on the dezincification of the CuZn39Pb3 alloy. Inductively coupled plasma spectroscopy (ICPS) and scanning electron microscopy (SEM) results confirm the high efficiency of ODT-SAMs in preventing the corrosion of the CuZn39Pb3 alloy. This is attributed to the formation of a compact ODT layer network, which stabilizes the alloy surface and impedes the infiltration of corrosive species and water to the substrate surface. [ABSTRACT FROM AUTHOR]

The long‐term consequences of electronic cigarette (Ecig) use in humans are not yet known, but it is known that Ecig aerosols contain many toxic compounds of concern. We have recently shown that Ecig exposure impairs middle cerebral artery (MCA) endothelial function and that it takes 3 days for MCA reactivity to return to normal. However, the sources contributing to impairment of the endothelium were not investigated. We hypothesized that the increased levels of oxidative stress markers in the blood are correlated with impaired MCA reactivity. We used electron paramagnetic resonance (EPR) spectroscopy to examine plasma from 4‐month‐old male Sprague–Dawley rats that were exposed to either air (n = 5) or 1 h Ecig exposure, after which blood samples were collected at varying times after exposure (i.e., 1–4, 24, 48 and 72 h postexposure, n = 4 or 5 in each time group). The EPR analyses were performed using the redox‐sensitive hydroxylamine spin probe 1‐hydroxy‐3‐carboxymethyl‐2,2,5,5‐tetramethyl‐pyrrolidine (CMH) to measure the level of reactive oxidant species in the plasma samples. We found that EPR signal intensity from the CM• radical was significantly increased in plasma at 1‐4, 24 and 48 h (P < 0.05, respectively) and returned to control (air) levels by 72 h. When evaluating the EPR results with MCA reactivity, we found a significant negative correlation (Pearson's P = 0.0027). These data indicate that impaired cerebrovascular reactivity resulting from vaping is associated with the oxidative stress level (measured by EPR from plasma) and indicate that a single 1 h vaping session can negatively influence vascular health for up to 3 days after vaping. Highlights: What is the central question of this study?Does the time course of oxidative stress triggered by electronic cigarette exposure follow the cerebral vascular dysfunction?What is the main finding and its importance?Electron paramagnetic resonance analysis shows that the oxidative stress induced after a single 1 h exposure to electronic cigarette aerosol takes ≤72 h to return to normal, which mirrors the time course for vascular dysfunction in the middle cerebral artery that we have reported previously. [ABSTRACT FROM AUTHOR]

In this study, a natural zeolite supported Co-B catalyst (Co-B/Zeolite) with a Co content of 10 wt.% was prepared by impregnation and chemical reduction method to release hydrogen gas from an alkaline sodium borohydride (NaBH4) solution. The synthesized catalyst was characterized with various characterization techniques, including X-ray diffraction (XRD), X-ray fluorescence (XRF), inductively coupled plasma mass spectroscopy (ICP-MS), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS), etc. It was found that the BET specific surface area of Co-B/Zeolite (26.03 m2 g−1) was roughly double that of the zeolite (13.12 m2 g−1). The Co ratio in the catalyst was found to be 12.02 wt.% by EDX analysis. ICP-MS examination of the catalyst revealed a B/Co atomic ratio of 0.64. No peaks associated with Co-B were observed in the XRD pattern of the catalyst, indicating the amorphous nature of the component. Parameters that have significant effects on the hydrolysis reaction, such as catalyst amount, sodium hydroxide and sodium borohydride concentrations, and reaction temperature, were investigated. The hydrogen generation rate (HGR) was found to be 1732 mL min−1 gcat−1 in the presence of 100 mg of Co-B/Zeolite in 5 wt.% NaOH and 5 wt.% NaBH4 solution at 50 °C. The experimental results were well fitted to the zero-order kinetic model (k0 = 0.0296–0.1619 mol min−1 gcat−1 for 20–50 °C). The activation energy (Ea) of the catalytic reaction was found to be 44.98 kJ mol−1. Meanwhile, the reusability evaluations showed that the catalyst preserves high stability and can still sustain 73% of its initial activity after 5 catalytic cycles. [ABSTRACT FROM AUTHOR]

Biogenic synthesis of papain-conjugated copper metallic Nanoparticles and their antibacterial and antifungal activities Papain metallic conjugated nanoparticles (Papain-CuNPs) were synthesised using Papain and CuSO4.5H2O. Papain-CuNPs were characterized using UV-visible spectroscopy, FT-IR (Fourier-Transform Infrared), HR-TEM (High-Resolution Transmission Electron Microscopy), XRD (X-ray diffraction), FE-SEM (Field-emission scanning electron microscopy), zeta potential, and a zeta sizer. The antibacterial activity of papain-CuNPs against human infectious microorganisms (Citrobacter spp, Pseudomonas aeruginosa and Candida albicans) was investigated. The mechanism of action of papain-CuNPs was evaluated using FE-SEM and HRTM. UV spectroscopy confirmed the plasma resonance (SPR) at 679 nm, which indicated the formation of papain-CuNPs. The FT-IR spectrum absorbance peaks at 3927, 3865, 3842, 3363, 2978, and 2900 cm-1 indicate the presence of O-H and N-H of the secondary amine, and peaks at 1643 and 1572 cm-1 represent C=O functional groups in Papain-CuNPs. EDAX analysis confirmed the presence of copper in the papain-CuNPs. The zeta potential (-42.6 mV) and zeta size (99.66 d. nm) confirmed the stability and size of the nanoparticles. XRD confirmed the crystalline nature of the papain-CuNPs. FE-SEM and HRTM showed an oval structure and the nano particles' 16.71244-34.84793 nm. The synthesized papain-NPs showed significant antibacterial activity against clinical P. aeruginosa (15 mm). MIC 125 µg/ml) showed bactericidal activity against P. aeruginosa and the mechanism of action of Papain-NPs was confirmed using an electron microscope by observing cell damage and cell shrinking. Papain-CuNPs have significant antibacterial activity and are thus used in the treatment of P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

Introduction and Objectives: Hepatocellular carcinoma (HCC) represents one of the most common cancers worldwide. A considerable proportion of HCC is caused by cirrhosis related to metabolic dysfunction-associated steatohepatitis (MASH). Due to the increasing prevalence of metabolic syndrome, it is estimated that MASH-related HCC will become the most prevalent etiology of HCC. Currently, HCC screening is based on liver ultrasonography; however, the sensitivity of ultrasonography for early HCC stages in obese patients only reaches 23 %. To date, no studied biomarker shows sufficient efficacy for screening purposes. Nevertheless, the usage of spectroscopic methods offers a new perspective, as its potential use would provide cheap, fast analysis of samples such as blood plasma. Material and Methods: We employed a combination of conventional and chiroptical spectroscopic methods to study differences between the blood plasma of obese cirrhotic patients with and without HCC. We included 20 subjects with HCC and 17 without evidence of liver cancer, all of them with body mass index ≥ 30. Results: Sensitivities and specificities reached values as follows: 0.780 and 0.905 for infrared spectroscopy, 0.700 and 0.767 for Raman spectroscopy, 0.840 and 0.743 for electronic circular dichroism, and 0.805 and 0.923 for Raman optical activity. The final combined classification model based on all spectroscopic methods reached a sensitivity of 0.810 and a specificity of 0.857, with the highest area under the receiver operating characteristic curve among all models (0.961). Conclusions: We suggest that this approach can be used effectively as a diagnostic tool in patients who are not examinable by liver ultrasonography. [ABSTRACT FROM AUTHOR]

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Thermal soil treatment is a well-established remediation method to remove organic contaminants from soils in waste management. The co-contamination with heavy metals raises the question if thermal soil treatment affects heavy metal mobility in soils. In this study, four contaminated soils and a reference sample were subjected to thermal treatment at 105°C, 300°C and 500°C for 7 day. Thermogravimetry and differential scanning calorimetry were used to understand the reactions, and resulting gases were identified by Fourier-transformed infrared spectroscopy. Treated and untreated samples were characterised by X-ray diffraction (XRD) and electron microprobe analysis and subjected to pH-dependent leaching tests, untreated samples additionally by X-ray-fluorescence (XRF) and inductively coupled plasma mass spectroscopy (ICP-MS). Leachates were analysed using ICP-MS and ion chromatography. Maximum available concentrations were used for hydrogeochemical modelling using LeachXS/Orchestra to predict leaching control mechanisms. Leaching experiments show that thermal treatment tends to decrease the mobility at alkaline pH of Pb, Zn, Cd, As and Cu, but to increase the mobility of Cr. In the acidic to neutral pH range, no clear trend is visible. Hydrogeochemical modelling suggests that adsorption processes play a key role in controlling leaching. It is suggested that the formation of minerals with a more negatively charged surface during thermal treatment are one reason why cations such as Pb2+, Zn2+, Cd2+ and Cu2+ are less mobile after treatment. Future research should focus on a more comprehensive mineralogical investigation of a larger number of samples, using higher resolution techniques such as nanoscale secondary ion mass spectrometry to identify surface phases formed during thermal treatment and/or leaching. [ABSTRACT FROM AUTHOR]

This study reports the effective synthesis of multilayered graphene sheets via microwave atmospheric pressure plasma. This innovative approach streamlines and expedites graphene production and other carbon nanostructures, eliminating the need for catalysts, solvents, or complex processing conditions. Ethanol is directly injected into a microwave-generated argon plasma plume, leading to the formation of graphene. Raman spectroscopy revealed characteristic peaks (2D, G, and D bands) confirming graphene composition, with defects indicated by the D band. X-ray diffraction analysis supported these findings, indicating a broad peak at 25∘ corresponding to the (002) plane, affirming a multi-layered graphene structure. Scanning electron microscopy exhibited crumpled, randomly oriented graphene sheets, albeit with uneven structures suggesting impurity incorporation. The presence of defects was quantified through the intensity ratio of the D to G band (ID/IG) in Raman spectroscopy, revealing a value of 0.80, signifying the presence of defects in the synthesized graphene. The 2D to G band intensity ratio (I2D/IG) suggested the existence of 7–10 graphene layers, highlighting the need for further optimization for enhanced graphene quality and purity. [ABSTRACT FROM AUTHOR]

The impaired function of the serotonin transporter (SERT) in humans has been linked to a higher risk of obesity and type 2 diabetes, especially as people age. Consuming a "Western diet" (WD), which is high in saturated fats, cholesterol, and sugars, can induce metabolic syndrome. Previous research indicated that mice carrying a targeted inactivation of the Sert gene (knockout, KO) and fed a WD display significant metabolic disturbances and behaviors reminiscent of ADHD. These abnormalities might be mediated via a dysfunction in insulin receptor (IR) signaling, which is also associated with adult ADHD. However, the impact of Sert deficiency on IR signaling and systemic metabolic changes has not been thoroughly explored. In this study, we conducted a detailed analysis of locomotor behavior in wild-type (WT) and KO mice fed a WD or control diet. We investigated changes in the blood metabolome and examined, via PCR, the expression of insulin receptor A and B isoforms and key regulators of their function in the brain. Twelve-month-old KO mice and their WT littermates were fed a WD for three weeks. Nuclear magnetic resonance spectroscopy analysis of plasma samples showed that KO mice on a WD had higher levels of lipids and lipoproteins and lower levels of glucose, lactate, alanine, valine, and isoleucine compared to other groups. SERT-KO mice on the control diet exhibited increased brain levels of both IR A and B isoforms, accompanied by a modest increase in the negative regulator ENPP. The KO mice also displayed anxiety-like behavior and reduced exploratory activity in an open field test. However, when the KO animals were fed a WD, the aberrant expression levels of IR isoforms in the KO mice and locomotor behavior were ameliorated indicating a complex interaction between genetic and dietary factors that might contribute to ADHD-like symptoms. Overall, our findings suggest that the lack of Sert leads to a unique metabolic phenotype in aged mice, characterized by dysregulated IR-related pathways. These changes are exacerbated by WD in the blood metabolome and are associated with behavioral abnormalities. [ABSTRACT FROM AUTHOR]

4‐(trimethylsilyl)morpholine O(CH2CH2)2NSi(CH3)3 (TMSM) was investigated as a single‐source precursor for SiCNO films synthesis. Optical emission spectroscopy of plasma generated from TMSM/He, TMSM/H2, and TMSM/NH3 gas mixtures revealed the presence of N2, CH, H, CN, and CO species. The last two are suggested to be responsible for the lowering of carbon concentration in the films in comparison with the precursor. The refractive index ranged from 1.5 to 2.0, and bandgap varied from 2.0 to 4.6 eV, which pointed that some of the films can be used as antireflective coatings in silicon photovoltaic cell technologies and dielectric layers in electronic devices. [ABSTRACT FROM AUTHOR]

Sagittally focusing x-ray crystal spectrometers with elliptical profiles in the meridional (x-ray dispersion) plane are proposed for plasma diagnostics in experiments accompanied by high neutron yields. The spectrometers feature a variable sagittal radius of curvature to ensure the sagittal focusing of rays for each photon energy in a chosen detection plane. The detector is placed after the ray crossing point at the second ellipse focus, and the source-to-detector distance is maximized to reduce the neutron-induced background. The elliptical shape imposes a limitation on the spectrometer geometry such that the influence of the source size on the spectral resolution can be avoided only for a demagnifying spectrometer (the source-to-crystal distance is larger than that of crystal-to-detector). Hence, two designs are proposed. The first design, featuring high magnification and limited spectral resolution can be suitable for x-ray continuum spectroscopy. The second design of high demagnification is optimized for spectral resolution, and can be used for time-resolved spectroscopy of plasma's characteristic emission lines using streak cameras. The key performance characteristics of the two designs are verified using ray tracing. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method for Virtual Metrology (VM) in plasma etch processes based on analysis of all time and wavelength samples of Optical Emission Spectroscopy (OES) signals. The new method flattens each OES signal into a single vector, after which Singular Value Decomposition (SVD) is performed on the matrix formed by vectors of flattened OES signals in the training dataset. Low rank SVD projections of flattened and standardized OES recordings served as inputs for Ridge Regression, Artificial Neural Network, and Random Forest based VM models. A VM study is then conducted on a dataset gathered from a major 300 mm wafer fabrication facility, showing that the use of newly proposed SVD-based OES features consistently outperformed benchmark VM model features. Additional analysis of feature importance performed based on the analytically tractable Ridge Regression VM model form demonstrated distinct time-frequency patterns of OES signal portions that were highly informative for prediction of relevant Critical Dimensions, clearly justifying the need to use the entire OES signals for VM. [ABSTRACT FROM AUTHOR]

The demand for pure uranium and uranium compounds of an industrial standard is tremendously increasing due to its wide array of utilities in electron microscopy, catalysis, armor-piercing, and nuclear explosions, among others. The raw ore and some of the products after alkaline leaching were characterized by X-ray fluorescence, X-ray diffraction, inductively coupled plasma mass spectroscopy, and scanning electron microscopy analyses. Dissolution kinetics and thermodynamics were examined under the experimental conditions at different sodium hydroxide concentrations, reaction temperature, and particle size towards purified uranyl leach liquor which could further be processed to industrial ammonium diuranate. The experimental results affirmed that the best parameters comprised a residence time of 120 min, reaction temperature of 75 °C, sodium hydroxide concentration of 2.5 mol/L, and particle size of 75 µm, yielding a dissolution efficiency of 96.1% with activation energy of 41.39 kJ/mol. [ABSTRACT FROM AUTHOR]

In the last decades, to improve the CAP treatment efficiency, its biological effects in combination with other physical modalities have widely investigated. However, the physical insight into most of supposed synergistic effects remained elusive. In this regard, the synergetic effect of cold plasma and magnetic field has been used for different applications, especially due to considerable synergistic in biological media reactivity. In the present paper, using a 420 mT N42 magnet, the effect of the perpendicular external static magnetic field (SMF) on the cold atmospheric pressure plasma (CAP) characteristics, such as electron temperature and density, is investigated based on the optical emission spectroscopy, utilizing the Boltzmann plot method, Saha-Boltzmann equation, and Specair software simulation. Results showed that the rotational and electronic excitational temperatures experienced 100 K and 550 K increases in the presence of SMF, respectively. In contrast, the vibrational and translational temperatures remained constant. Moreover, electron temperature was estimated as 1.04 eV in the absence of SMF and increased up to 1.24 eV in the presence of SMF. In addition, the Saha-Boltzmann equation illustrated that the electron density increased in the presence of the additional SMF. The results of the present study indicated that the magnetic field could be an assistant to the cold plasma effect, beneficial in medical applications due to modifications in plasma temperature and electron density. [ABSTRACT FROM AUTHOR]

The study used the radio-analytical technique (Neutron Activation Analysis), besides the other advanced chemical technique, which was inductively coupled plasma mass spectroscopy (ICP-MS), in order to evaluate the bioaccumulation factor (BF), of different trace elements inside the collected green macro algal samples. The results showed that BF results were based on the algal selectivity of each analyzed trace element. The study recommended the using of Ulva fasciata, as a bio-filter of nuclear cooling water system (mitigation tool), due to its selective absorption ability for certain trace elements such as; Th, Cs &Sr. [ABSTRACT FROM AUTHOR]

The morphology and crystalline quality of polycrystalline diamond samples were studied by systematically varying the flowrate of nitrogen gas in the microwave plasma. A slight improvement in both crystallite size and crystalline quality is observed for a low concentration of 0.5 sccm nitrogen. With a further increase in nitrogen concentration, diamond switches from micro-crystalline to nanocrystalline (NCD) with a nitrogen flow of 2.5 sccm (10% of methane concentration). The surface roughness of the sample is found to depend strongly on the crystallite size of the sample. Extensive spectroscopic studies have been done to understand the presence and formation of different defect complexes in diamond. XPS and Raman analysis of the films reveal the variation of graphitic content as a function of nitrogen addition. The presence of nitrogen-containing defect complexes has been studied thoroughly and their concentration has been found to be limited by the solubility limit rather than the availability of reactants in the gas environment. In contrast, the effect these complexes have on the strain of the diamond film is found to be negligible. Optical emission spectroscopy of the plasma reveals the presence of C2 dimers as well as C-N radicals. However, they have little role in modifying diamond grain morphology or crystalline quality. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM) is a pregnancy disorder associated with short‐ and long‐term adverse outcomes in both mothers and infants. The current clinical test of blood glucose levels late in the second trimester is inadequate for early detection of GDM. Here we show the utility of Raman spectroscopy (RS) for rapid and highly sensitive maternal metabolome screening for GDM in the first trimester. Key metabolites, including phospholipids, carbohydrates, and major amino acids, were identified with RS and validated with mass spectrometry, enabling insights into associated metabolic pathway enrichment. Using classical machine learning (ML) approaches, we showed the performance of the RS metabolic model (cross‐validation AUC 0.97) surpassed that achieved with patients' clinical data alone (cross‐validation AUC 0.59) or prior studies with single biomarkers. Further, we analyzed novel proteins and identified fetuin‐A as a promising candidate for early GDM prediction. A correlation analysis showed a moderate to strong correlation between multiple metabolites and proteins, suggesting a combined protein‐metabolic analysis integrated with ML would enable a powerful screening platform for first trimester diagnosis. Our study underscores RS metabolic profiling as a cost‐effective tool that can be integrated into the current clinical workflow for accurate risk stratification of GDM and to improve both maternal and neonatal outcomes. [ABSTRACT FROM AUTHOR]

Celiac Disease (CD) is a primary malabsorption syndrome resulting from the interplay of genetic, immune, and dietary factors. CD negatively impacts daily activities and may lead to conditions such as osteoporosis, malignancies in the small intestine, ulcerative jejunitis, and enteritis, ultimately causing severe malnutrition. Therefore, an effective and rapid differentiation between healthy individuals and those with celiac disease is crucial for early diagnosis and treatment. This study utilizes Raman spectroscopy combined with deep learning models to achieve a non-invasive, rapid, and accurate diagnostic method for celiac disease and healthy controls. A total of 59 plasma samples, comprising 29 celiac disease cases and 30 healthy controls, were collected for experimental purposes. Convolutional Neural Network (CNN), Multi-Scale Convolutional Neural Network (MCNN), Residual Network (ResNet), and Deep Residual Shrinkage Network (DRSN) classification models were employed. The accuracy rates for these models were found to be 86.67%, 90.76%, 86.67% and 95.00%, respectively. Comparative validation results revealed that the DRSN model exhibited the best performance, with an AUC value and accuracy of 97.60% and 95%, respectively. This confirms the superiority of Raman spectroscopy combined with deep learning in the diagnosis of celiac disease. [ABSTRACT FROM AUTHOR]

The results of experiments on the generation of soft X-ray pulses in the "water window" region performed on a compact gas-discharge source are presented. The parameters of the radiation source were optimized based on the condition of reducing the intensity of capillary wall ablation and obtaining the maximum intensity of the helium-like nitrogen ion N VI—2.88 nm. The obtained results can be used in the development of a microscope for the tasks of cell microscopy with nanometer resolution. [ABSTRACT FROM AUTHOR]

The use of a new nanomaterial in the feed chain requires a risk assessment that involves in vitro gastrointestinal digestions to predict its degradation and oral exposure to nanoparticles. In this study, a nanosilver-based material was incorporated into pig and chicken feed as a growth-promoting additive and subjected to the corresponding in vitro gastrointestinal digestions. An inductively coupled plasma mass spectroscopy (ICP-MS) analytical platform was used to obtain information about the silver released in the different digestion phases. It included conventional ICP-MS for total silver determination, but also single particle ICP-MS and coupling to hydrodynamic chromatography for detection of dissolved and particulate silver. The bioaccessible fraction in the intestinal phase accounted for 8–13% of the total silver, mainly in the form of dissolved Ag(I) species, with less than 0.1% as silver-containing particles. Despite the additive behaving differently in pig and chicken digestions, the feed matrix played a relevant role in the fate of the silver. [ABSTRACT FROM AUTHOR]

CO2 mineralization in slag has been widely investigated as a potential solution for offsetting steelmaking industry emissions. However, it can be associated with ecotoxic elements release (e.g., V and Cr). The presence of such elements in heterogenous slag at the micro‐scale remains difficult for analysis since microstructural features can be missed during microscopy data inspection, thereby presenting a challenge in understanding how ecotoxic elements exist in slag. Here, an unsupervised machine learning‐based technique is used to analyze slag's microstructural features. Energy Dispersive Spectroscopy (EDS) data are analyzed through Hierarchical Density‐Based Spatial Clustering of Applications with Noise (HDBSCAN) method. Results show that passive CO2 mineralization has occurred in situ in the studied samples, on the surface, and within their pores. Additionally, V and Cr regions with equivalent diameters < 42 µm can exist within slag, potentially making such elements prone to mobilization due to slag pulverization. Interrogation of the samples with Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA‐ICP‐MS) confirms the distribution of the elements obtained from the clustering algorithm and further demonstrates that up to 84 and 9 ppm of V and Cr are incorporated in the precipitated calcite, respectively. This implies that ecotoxic elements may be immobilized through calcite precipitation. [ABSTRACT FROM AUTHOR]

This contribution attempts to provide a state-of-the-art account of the physicochemical and biomedical properties of the plasma-sprayed hydroxylapatite (HAp) coatings that are routinely applied to the surfaces of metallic endoprosthetic and dental root implants designed to replace or restore the lost functions of diseased or damaged tissues of the human body. Even though the residence time of powder particles of HAp in the plasma jet is extremely short, the high temperature applied induces compositional and structural changes in the precursor HAp that severely affect its chemical and physical properties and in turn its biomedical performance. These changes are based on the incongruent melting behavior of HAp and can be traced, among many other analytical techniques, by high resolution synchrotron X-ray diffraction, vibrational (Raman) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. In vivo reactions of the plasma-sprayed coatings to extracellular fluid (ECF) can be assessed and predicted by in vitro testing using simulated body fluids (SBFs) as proxy agents. Ways to safeguard the appropriate biological performance of HAp coatings in long-term service by controlling their phase content, porosity, surface roughness, residual stress distribution, and adhesion to the implant surface are being discussed. [ABSTRACT FROM AUTHOR]

In this study, gold and silver nanoparticles (Au NPs, and Ag NPs) were prepared by laser ablation in water using Nd:YAG laser at wavelength is 1064 nm, 1 Hz frequency. The prepared nanoparticles were deposited on a silicon wafer of (100) direction by dip coating technique. The FE-SEM results showed the nanoparticles that the spherical shapes with the average size (13.9, 12.09) nm and The structural properties were identified using the XRD results were showed the crystal size that were (10.9, 12.1) nm for each of the Au NPs, Ag NPs, respectively. The plasma parameters were studied from the emission spectra such as temperature, Debye length, and electron density, and there were some differences between the bulk target and the nanoenhanced target. The results showed some differences in the peaks of atomic transitions in terms of intensity. The variation in the mechanism of laser-matter interaction with exist of the nanoparticles causes to enhances the emission line more than two folds. The generation mechanism of seeds electron may reduce the breakdown threshold, so increase the intensity of characteristics lines and enhance the LIBS detectability, especially for the wavelength range from 400 to 550 nm. Both plasma number density and plasma temperature increased nano-enhanced plasma by Au NPs or Ag NPs compared with the bare surface. It is possible to benefit from the improvement in some optoelectronic applications. [ABSTRACT FROM AUTHOR]

Spatial confinement effects offered by a blocker on the laser-induced plasma parameters of titanium (Ti) are evaluated using the Optical Emission Spectroscopy technique. Nd:YAG (1064 nm, 10 ns) laser is used as an irradiation source. To observe the spatial confinement effects, an Al blocker at different distances of 4, 6, and 8 mm from the target is placed along the plume path. All the measurements are performed under the Ar environment at different pressures. It is observed that with increasing laser irradiance plasma parameters such as excitation temperature (Te) and electron number density (ne) increase, whereas it is vice versa true for increasing blocker distances. Without the blocker, the maximum values of Te and ne are about 7000 K and 1.4 × 1018 cm−3, respectively, at an Ar pressure of 50 Torr. A significant increase in emission intensity along with Te ≈ 9810 K and ne ≈ 2.2 × 1018 cm−3 is achieved in the presence of blocker. The results show that spatial confinement is responsible for the enhancement of Te and ne, which is attributed to the increased collisional frequency of plasma species after compression by shockwaves. The ablation pressure and shock pressure are also analytically evaluated and vary from 0.15 to 0.25 GPa and from 0.1 to 0.2 GPa, respectively, with increasing laser irradiance. With increasing blocker distances from 4 to 8 mm, the work done by reflected shockwaves to compress the plume varies from 0.02 to 0.002 mJ. [ABSTRACT FROM AUTHOR]

The possibility of using plasma electron spectroscopy (PLES) as a practical method for the detection and identification of crystalline impurities of salts: silver salts, as well as ammonium salts, used in explosives and dangerous substances is shown. To create a prototype of the PLES detector, relatively simple technical solutions are adopted. The source of excitation of metastable atoms is a short DC glow discharge. For analysis, probe scheme for registering electric current from an auxiliary additional electrode probe is used when scanning the retarding electric potential. As a result of a series of experiments, the possibility of detecting products, cathode sputtering, and decomposition of ammonium and silver salts was shown. In particular, peaks from ammonia, nitrogen oxide, silver, and chlorine were recorded. [ABSTRACT FROM AUTHOR]

Salinity stress is a major factor affecting the nutritional and metabolic profiles of crops, thus hindering optimal yield and productivity. Recent advances in nanotechnology propose an avenue for the use of nano-fertilizers as a potential solution for better nutrient management and stress mitigation. This study aimed to evaluate the benefits of conventional and nano-fertilizers (nano-Zn/nano-Si) on maize and subcellular level changes in its ionomic and metabolic profiles under salt stress conditions. Zinc and silicon were applied both in conventional and nano-fertilizer-using farms under stress (100 mM NaCl) and normal conditions. Different ions, sugars, and organic acids (OAs) were determined using ion chromatography and inductively coupled plasma mass spectroscopy (ICP-MS). The results revealed significant improvements in different ions, sugars, OAs, and other metabolic profiles of maize. Nanoparticles boosted sugar metabolism, as evidenced by increased glucose, fructose, and sucrose concentrations, and improved nutrient uptake, indicated by higher nitrate, sulfate, and phosphate levels. Particularly, nano-fertilizers effectively limited Na accumulation under saline conditions and enhanced maize's salt stress tolerance. Furthermore, nano-treatments optimized the potassium-to-sodium ratio, a critical factor in maintaining ionic homeostasis under stress conditions. With the growing threat of salinity stress on global food security, these findings highlight the urgent need for further development and implementation of effective solutions like the application of nano-fertilizers in mitigating the negative impact of salinity on plant growth and productivity. However, this controlled environment limits the direct applicability to field conditions and needs future research, particularly long-term field trials, to confirm such results of nano-fertilizers against salinity stress and their economic viability towards sustainable agriculture. [ABSTRACT FROM AUTHOR]

Active plasma resonance spectroscopy (APRS) is a process-compatible plasma diagnostic method, which utilizes the natural ability of plasmas to resonate on or near the electron plasma frequency. The multipole resonance probe (MRP) is a particular design of APRS that has a high degree of geometric and electric symmetry. The principle of the MRP can be described on the basis of an idealized geometry that is particularly suited for theoretical investigations. In a pressure regime of a few Pa or lower, kinetic effects become important, which cannot be predicted by the Drude model. Therefore, in this paper, a dynamic model of the interaction of the idealized MRP with a plasma is established. The proposed scheme reveals the kinetic behavior of the plasma that is able to explain the influence of kinetic effects on the resonance structure. Similar to particle-in-cell, the spectral kinetic method iteratively determines the electric field at each particle position, however, without employing any numerical grids. The optimized analytical model ensures the high efficiency of the simulation. Eventually, the presented work is expected to cover the limitation of the Drude model, especially for the determination of the pure collisionless damping caused by kinetic effects. A formula to determine the electron temperature from the half-width Δ ω is proposed. [ABSTRACT FROM AUTHOR]

Phosphorous (P) is an essential element for plant growth and development, and its scarcity is a severe crop output constraint. Determination of total P in soil and fertilizers is very important in agriculture as the amount of P is related to crop production. Rock phosphate (RP) is an excellent natural source of P widely used for P fertilizer production. The objective of this study was to compare two different digestion methods, microwave digestion and hot plate digestion, and to evaluate the performance of two analytical techniques, inductively coupled plasma mass spectroscopy (ICP-MS) and colorimetry (UV-VIS), for measuring total P in imported RP samples. The validation of microwave digestion followed by analysis in ICP-MS was performed. Phosphorus has detection and quantification limits of 1 mg L−1 and 5 mg L−1 respectively through ICP-MS analysis. Average P recovery was found 92.12–96.53%. Precision in terms of intra-day (%RSDR = 2.76–5.98 evaluated using ICP-MS) and inter-day (%RSDr = 2.92–6.75) were found to be within the acceptable range (20%), indicating consistency of the proposed method to determine total-P over traditional UV-VIS method. The combination of microwave-assisted digestion and ICP-MS offers superior efficiency in determining both phosphorus (P) and heavy metals, including aluminum, iron, zinc, cadmium, strontium, manganese and chromium, in RP samples. Hence, this method is novel and rapid and is used for the quantification of total P in different RP samples for quality control. [ABSTRACT FROM AUTHOR]

We propose the application of helium line intensity ratio spectroscopy in a low-pressure (0.3 mTorr) xenon E × B discharge with an electron temperature of ∼2 eV and a density of 10 10 − 10 11 cm − 3 . We successfully identified the helium atom line emissions at 388.9, 447.1, 501.6, 504.8, and 706.5 nm with helium pressures of up to ∼20 mTorr. The measured electron temperature, density, and I − V characteristics of the discharge remained almost constant in all helium pressures in the present experiment, indicating the suitability of the helium gas as a diagnostic gas. The results of helium line intensity ratio spectroscopy using the line emissions at 388.9, 447.1, and 504.8 nm showed fair agreement with the Langmuir probe measurement. Considering the trade-off relationship between the disturbance introduced by the helium gas and the signal-to-noise ratio, we conclude that a helium pressure of approximately 4 mTorr (approximately 13 times the partial pressure of xenon) represents the optimal pressure range for the application of the helium line emission intensity ratio method to this xenon plasma. It is found that the use of the line emissions at 501.6 and 706.5 nm result in a significant disturbance in the helium line intensity ratio method due to the radiation trapping effect. [ABSTRACT FROM AUTHOR]

Pollutants accumulate in aquatic habitats due to mining activities. The duckweed family includes water plants such as Lemna gibba and Lemna minor, which are tiny, delicate, free-floating aquatic plants. L. minor and L. gibba were used in this study to examine the accumulation capacities of Mo4+, Pb++, and Cu++ in acidic fluids from copper mining. Two reactors were assigned to L. gibba and L. minor, respectively. These plants and the reactor water were gathered daily for 8 days. Acid mine water pH, temperature, and electric conductivity were also tested daily. L. gibba and L. minor were cleaned, dehydrated, and burned in a drying oven for a whole day at 300 °C. ICP-MS (inductively coupled plasma mass spectroscopy) was used to determine the Mo4+, Pb++, and Cu++ content of the plant and water samples. The Mo, Pb, and Cu concentrations in the copper mining acidic fluids were 30 ± 4, 260 ± 12, and 15,535 ± 322 μg L−1, respectively. Regarding Mo, Pb, and Cu extraction from copper mining acidic fluids, L. gibba and L. minor performed more efficiently than control samples, gathering 29 and 177 times more Mo, 30 and 109 times more Pb, and 495 and 1150 times more Cu, respectively. Considering these findings, L. gibba and L. minor are good plants for rehabilitating polluted waters and can efficiently remove Mo, Pb, and Cu from acid mine fluids. [ABSTRACT FROM AUTHOR]

The determination of the composition and timing sequence of products during the detonation of energetic materials is crucial for the evaluation of detonation performance and improvement of the formulation. However, it is difficult to determine the detonation products of energetic materials due to the fast reaction time during detonation. Herein, a new setup is built to detect the detonation products of energetic materials by time correlated laser induced plasma spectroscopy (LIPS) combined with high-speed schlieren imaging. The characteristics of time resolution and spatial distribution of propellant products from laser induced micro-detonation are obtained using the system. According to the time resolved spectrum of the products and high-speed schlieren images of laser induced micro-detonation, we speculate on the timing sequence of gaseous propellant products from laser induced micro-detonation in air: N2, O2, and nitrogen oxides precede hydrocarbon gases, followed by carbon oxides and gaseous containing the element of H. Moreover, the distribution of the gaseous products from laser induced micro-detonation are clarified. This study provides a new method for the detection of products during the detonation of energetic materials. [ABSTRACT FROM AUTHOR]

The emission sources of fine particulate matter (PM2.5) have not yet been fully identified in Ho Chi Minh City (HCMC), Vietnam, presenting difficulties to authorities in controlling air pollution efficiently. To address this issue, this study explores the source apportionment of PM2.5 by the positive matrix factorization (PMF) model and identifies potential regional sources through the weighted concentration-weighted trajectory (WCWT) model based on the field observation data of PM2.5 in HCMC. 24-h PM2.5 samples were collected in central HCMC for a year (September 2019–August 2020). Herein, inductively coupled plasma mass spectroscopy was used to analyze trace elements, in addition to identifying PM2.5 mass and other chemical species, such as water-soluble ions and carbonaceous species, reported in our former study. The PMF results showed that PM2.5 in HCMC was dominated by anthropogenic-rich sources comprising biomass burning, coal combustion, transportation, and crustal origins (36.4% of PM2.5 mass), followed by secondary ammonium sulfate (18.4%), sea salt (13.7%), road dust (9.6%), and coal and crude oil combustion (9.4%). WCWT results suggested that the geological sources of PM2.5 were mainly from local areas and scattered to the northeast/southwest of HCMC. In addition, the long-range transport of PM2.5 from surrounding countries was revealed during the assembly restriction and lockdown period in 2020. [ABSTRACT FROM AUTHOR]

HIV-exposed, uninfected (HEU) children present with suboptimal growth and a greater susceptibility to infection in early life when compared to HIV-unexposed, uninfected (HUU) children. The reasons for these findings are poorly understood. We used a metabolomics approach to investigate the metabolic differences between pregnant women living with HIV (PWLWH) and their HEU infants compared to the uninfected and unexposed controls. Untargeted metabolomic profiling was performed using 1H-NMR spectroscopy on maternal plasma at 28 weeks' gestation and infant plasma at birth, 6/10 weeks, and 6 months. PWLWH were older but, apart from a larger 28 week mid-upper-arm circumference, anthropometrically similar to the controls. At all the time points, HEU infants had a significantly reduced growth compared to HUU infants. PWLWH had lower plasma 3-hydroxybutyric acid, acetoacetic acid, and acetic acid levels. In infants at birth, threonine and myo-inositol levels were lower in the HEU group while formic acid levels were higher. At 6/10 weeks, betaine and tyrosine levels were lower in the HEU group. Finally, at six months, 3-hydroxyisobutyric acid levels were lower while glycine levels were higher in the HEU infants. The NMR analysis has provided preliminary information indicating differences between HEU and HUU infants' plasma metabolites involved in energy utilization, growth, and protection from infection. [ABSTRACT FROM AUTHOR]

We have developed a digitally processed DC reactive sputtering (DPDRS) system that enables synthesis of arbitrarily designed atomically precise deposition of metal oxide compounds. Pulsed-DC sputtering employing a digital pulse pattern generator can perform the temporally alternating process of multiple metal sputtering and oxidation. High-speed switching of the pulsed-DC sputtering process driven by the digital signal processing was confirmed from time-resolved plasma emission spectroscopy. Metal sputtering, which was temporally separated from the oxidation process, resulted in a deposition rate higher than 1 μm/h. It was also found that the temporally separated radical oxidation at the deposited metal surface could control the oxidation process. The DPDRS was applied to layer-by-layer synthesis of (Er0.1Y0.9)2SiO5 (EYSO) films oriented to the ⟨100⟩ direction. The deposition rate for each metal target (Er and Y) was adjusted to 0.86 nm/cycle corresponding to a d-spacing of the (100) plane by changing independently the duty ratio of the base pulse for plasma generation. X-ray diffraction measurements indicated a formation of ⟨100⟩ highly oriented (Er0.1Y0.9)2SiO5 crystalline thin films. Photoluminescence spectra and the decay characteristics also showed synthesis of high crystalline quality EYSO films better than those obtained by pulsed laser deposition. [ABSTRACT FROM AUTHOR]

Mangrove areas are considered the most retention zone for heavy metal pollution as it work as an edge that aggregates land and sea sediments. This study aims to examine if the heavy metals' existence in the mangrove sediment is related to contamination or natural resources. In addition, it gives an interpretation of the origin of these metals along the Egyptian Red Sea coast. Twenty-two samples of mangrove sediments were collected and then, analyzed for metals (Mn, Ni, Cu, Fe, Cd, Ag, and Pb) using inductively coupled plasma mass spectroscopy (ICP-MS). Integration between the in-situ data, contamination indices, and remote sensing and geographical information science (GIS), and multivariate statistical analysis techniques (PCA) were analyzed to assess and clarify the spatial origin of heavy metals in sediment at a regional scale. The average concentration of heavy metals from mangrove sediments were shown to be substantially lower than the referenced value, ranging from moderate to significant except the levels of Ag were very high. The heavy metals concentrations were expected to be naturally origin rather than anthropogenic and that be confirmed by mapping of Red Sea alteration zones spots. These alteration zones are parallel to mangrove sites and rich by several mineralization types including heavy metals that are carried by flooding to the coastline. Remote sensing and GIS techniques successfully contributed to interpreting the pattern of the origin of heavy metals and discharging systems that control the heavy metals concentration along the Red Sea coast. [ABSTRACT FROM AUTHOR]

Parameters of electron-impact (Stark) broadening and shift of spectral lines are of key importance in various studies of plasma spectroscopy and astrophysics. To overcome the lack of accurately known Stark parameters, we developed a machine learning approach for predicting Stark parameters of neutral atoms' lines. By implementing a data pre-processing routine and explicitly testing models' predictive ability and generalizability, we achieve a high level of accuracy in parameters prediction as well as physically meaningful temperature dependence. The applicability of the results is demonstrated by the case of low-temperature plasma diagnostics. The developed model is readily accessible for predicting desired Stark parameters. [ABSTRACT FROM AUTHOR]

This study investigated the effect of temperature on the aspect-ratio etching of SiO2 in CF4/H2/Ar plasma using patterned samples of a 200 nm trench in a low-temperature reactive-ion etching system. Lower temperatures resulted in higher etch rates and aspect ratios for SiO2. However, the plasma property was constant with the chuck temperature, indicated by the line intensity ratio from optical emission spectroscopy monitoring of the plasma. The variables obtained from the characterization of the etched profile for the 200 nm trench after etching were analyzed as a function of temperature. A reduction in the necking ratio affected the etch rate and aspect ratio of SiO2. The etching mechanism of the aspect ratio etching of SiO2 was discussed based on the results of the surface composition at necking via energy-dispersive X-ray spectroscopy with temperature. The results suggested that the neutral species reaching the etch front of SiO2 had a low sticking coefficient. The bowing ratio decreased with lowering temperature, indicating the presence of directional ions during etching. Therefore, a lower temperature for the aspect ratio etching of SiO2 could achieve a faster etch rate and a higher aspect ratio of SiO2 via the reduction of necking than higher temperatures. [ABSTRACT FROM AUTHOR]

The development of measurement methodologies to detect and monitor nuclear-relevant materials remains a consistent and significant interest across the nuclear energy, nonproliferation, safeguards, and forensics communities. Optical spectroscopy of laser-produced plasmas is becoming an increasingly popular diagnostic technique to measure radiological and nuclear materials in the field without sample preparation, where current capabilities encompass the standoff, isotopically resolved and phase-identifiable (e.g., UO and UO 2) detection of elements across the periodic table. These methods rely on the process of laser ablation (LA), where a high-powered pulsed laser is used to excite a sample (solid, liquid, or gas) into a luminous microplasma that rapidly undergoes de-excitation through the emission of electromagnetic radiation, which serves as a spectroscopic fingerprint for that sample. This review focuses on LA plasmas and spectroscopy for nuclear applications, covering topics from the wide-area environmental sampling and atmospheric sensing of radionuclides to recent implementations of multivariate machine learning methods that work to enable the real-time analysis of spectrochemical measurements with an emphasis on fundamental research and development activities over the past two decades. Background on the physical breakdown mechanisms and interactions of matter with nanosecond and ultrafast laser pulses that lead to the generation of laser-produced microplasmas is provided, followed by a description of the transient spatiotemporal plasma conditions that control the behavior of spectroscopic signatures recorded by analytical methods in atomic and molecular spectroscopy. High-temperature chemical and thermodynamic processes governing reactive LA plasmas are also examined alongside investigations into the condensation pathways of the plasma, which are believed to serve as chemical surrogates for fallout particles formed in nuclear fireballs. Laser-supported absorption waves and laser-induced shockwaves that accompany LA plasmas are also discussed, which could provide insights into atmospheric ionization phenomena from strong shocks following nuclear detonations. Furthermore, the standoff detection of trace radioactive aerosols and fission gases is reviewed in the context of monitoring atmospheric radiation plumes and off-gas streams of molten salt reactors. Finally, concluding remarks will present future outlooks on the role of LA plasma spectroscopy in the nuclear community. [ABSTRACT FROM AUTHOR]

A total of 25 samples of beeswax (9 from the southern and 16 from the northern of Çankırı) were collected within the scope of this study. Heavy metal contents of these samples were analyzed by using inductively coupled plasma mass spectroscopy (ICP-MS). The mean iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), lead (Pb), aluminum (Al), chromium (Cr), vanadium (V), cadmium (Cd), selenium (Se) levels in the samples were found to be 36.28 ppm, 1.69 ppm, 1.65 ppm, 1.14 ppm, 0.78 ppm, 0.68 ppm, 0.30 ppm, 0.13 ppm, 0.06 ppm, 0.01 ppm, respectively. Comparing the northern and southern regions, only Cd (1.10 ppm) was found to be higher in the southern region, whereas the other heavy metals were found to be higher in the northern region. No statistical difference was found between mean Fe, Pb, Zn, Al, Cr, V, and Se levels in the wax samples obtained from the northern and southern regions, whereas a statistically significant difference was found in Mn, Cu, and Cd concentrations. As a result, the heavy metal concentration in beeswax varied between the regions. Except for Cd element, all values were higher in the northern region of Çankırı and this region that is close to the highway with heavy traffic should be evaluated in terms of beekeeping. [ABSTRACT FROM AUTHOR]

It is indispensable to accurately and sensitively identify and analyze the elemental composition of human blood serum. In the current study, human blood serums were analyzed for elements utilizing orthogonal dual pulse laser-induced breakdown spectroscopy (DP-LIBS) setup in He gas environment. Experimentally, a fundamental pulse Nd:YAG laser (1064 nm, 7 ns) was irradiated just above the material target to induce a luminous gas plasma. A third harmonic pulse Nd:YAG laser (355 nm, 7 ns) was subsequently focused on the material surface to initiate a target plasma to ablate the atoms from the blood serum film to be sent to the gas plasma region. Double pulse LIBS technique has been successfully applied to increase the LIBS signal intensity up to 8 folds of major, minor, and trace components in human blood serum. Furthermore, a number of emission lines that were indistinctly detected by single pulse LIBS were accurately identified with the use of the DP-LIBS. A variety of components from the human blood serum have been analyzed both qualitatively and quantitatively. Element concentrations measured in human blood are to be 8360 ppm, 219 ppm, 581 ppm, 785 ppm, 343 ppm, 293 ppm, and 12 ppm for C, Ca, K, Mg, P, Na, and Fe, respectively. The LIBS outcome results are in excellent agreement with the results acquired by applying the standard XRF technique. [ABSTRACT FROM AUTHOR]