Inductively Coupled Plasma Optical Emission Spectrometry Research Articles

Dynamic-Permeability Variations Induced During CO2-EOR Application in Carbonate Reservoirs: Upper Red River Formation, North Dakota

Summary Carbonate-based mineral dissolution and precipitation, driven by carbon dioxide (CO2) injection, introduces complexities to carbonate reservoir systems that trigger interactions different from those seen in traditional CO2-enhanced oil recovery (CO2-EOR) applications in siliciclastic/sandstone reservoirs. The thrust of this paper is to couple experimental (laboratory-scale) and numerical (computationally-assisted) analyses in order to assess how CO2-induced petrophysical alterations impact the resultant hydrocarbon recovery from CO2-EOR applications in carbonate reservoirs. The Upper Red River Formation, located in North Dakota’s Cedar Creek Anticline (CCA) Field, presents significant remaining oil in place (OIP), albeit with a high water saturation from waterflood operations undergoing since the 1960s. The residual oil saturation (post-waterflooding) makes the Upper Red River Formation a good target for modern-day CO2-EOR technology. The first part of this study involves a core-scale investigation of dynamic-permeability variations triggered by the CO2 injection into three primary-productive zones, designated as “Red River Units” (RRU2, RRU4, and RRU6). The second part involves a compositional reservoir model used to perform numerical simulations of CO2 injection incorporating pre-established dynamic-permeability variations that honor the laboratory-obtained results. Correlations between differential-pressure variations observed during carbonated brine (CO2/brine mixture) injection were assessed against pore volumes injected (PVI). These pressure fluctuations were induced by dynamic-permeability variations resulting from carbonate-based mineral dissolutions/precipitations. Baseline-permeability variations were established a priori using nitrogenated-brine (N2/brine) injection to correct for physicochemical effects from the brine. During CO2/brine injection, the recorded permeability increased significantly compared to its original value, peaking before sharply decreasing. Inductively coupled plasma optical emission spectrometry (ICP-OES) and scanning electron microscopy (SEM) were utilized for deciphering the triggers of these dynamic-permeability variations, which revolve around mineral dissolutions and precipitations following the carbonate rock’s exposure to CO2. The history-matched compositional reservoir model was used to project the incremental production from CO2-EOR through a section incorporating four existing wells, incorporating the laboratory-derived dynamic-permeability variations, yielding different results compared with “base case” simulations performed at constant permeability. Reduced reservoir permeability correlated with decreased oil recovery, emphasizing the significant impact of dynamic-permeability variations on CO2-EOR performance and hence the importance of their integration in fieldwide development analyses.

Steam reforming of dodecane using Ni-red mud catalyst: A sustainable approach for hydrogen production

Conventional energy sources emit huge amounts of carbon dioxide (CO2) into the atmosphere causing global warming. Hydrogen (H2) is an alternative clean energy carrier that produces only heat and water vapor upon combustion. In this work, we utilized industrial waste material (Red Mud, RM) to develop a cost-effective and efficient catalyst for steam reforming of diesel (n-dodecane as a model compound) for hydrogen production. We impregnated nickel (Ni), a prudent and effective metal, in red mud (RM) in varied proportions to employ as a catalyst for hydrogen production. The catalysts' structure was characterized by powdered X-ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Electron Dispersive Spectroscopy (EDS) were used to measure the elemental composition while Scanning Electron Microscopy (SEM) was used to investigate the catalysts’ morphology. Surface area and porosity were analyzed using the N2 adsorption/desorption isotherms, and H2-Temperature Programmed Reduction (H2-TPR) to study the reducibility and interaction of Ni species to the RM. The catalysts were then evaluated for hydrogen production by the steam reforming process of n-dodecane (SRD). It was found that the catalyst with 20% Ni loading (20% Ni@RM) can produce hydrogen with selectivity as high as 75%, and stability for 20 h with a negligible decline in the catalyst performance.

Microwave-induced plasma optical emission spectrometry (MIP-OES) analysis of the major elements in woody biomass ash following microwave acid digestion

The increasing use of woody biomass for sustainable heat and power is generating large amounts of woody biomass ash (WBA), which needs to be safely disposed of or recycled. In this study, the utility of Microwave-induced plasma optical emission spectrometry (MIP-OES) with microwave-assisted acid digestion for simplifying analyses of the major elements of WBA was investigated. Calibration curves exhibited good linearity (R2 > 0.999). Internal standardization using three emissions lines (324.754 nm of Cu, 451.131 nm of In and 371.029 nm of Y) showed that calibration with Cu (324.754 nm) correction resulted in the best linearity. Physical effects, even the presence of hydrofluoric acid or boric acid in mixed acids used for digestion, were of trivial influence with internal standard recoveries were within 0.95 to 1.05 times those of the blank sample. The limit of detection of MIP-OES for seven measured elements was 0.85–89 μg/L, 0.23–2.8 times higher than that of inductively coupled plasma optical emission spectrometry (ICP-OES). The recovery of elements in a certified fly ash reference material as determined by MIP-OES was 0.80–1.08. Elemental quantification of WBA samples by MIP-OES showed a strong correlation with that by ICP-OES. However, in a Welch's t-test, the MIP-OES values were significantly higher for K and significantly lower for Al and Ca in a majority of the samples. Nonetheless, considering the good correlation between their results, MIP-OES can replace ICP-OES for the analysis of WBA.

Investigation of mercury contamination in lipstick sold in the Saudi market and the potential health risk

Background: Environmental contamination is a significant global health issue, with cosmetics and pharmaceuticals being major polluters. High concentrations of heavy metals, such as Hg, have been found to have toxic effects and may pose a threat to human health. This study aimed to determine the concentration of mercury (Hg) in lipsticks available in the Saudi Arabia market. Methods: In this study, 12 lipstick samples from three colors were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES) to measure the content of Hg. Results: The concentration range of Hg was 0.004–0.296 ppm. Moreover, the systemic exposure dosage of mercury in the lipstick samples examined in this study ranged from 5.01 × 10−8 to 1.43 × 10−6 μg/kg bw/day, while the range of the margin of safety was from 7.3 × 109 to 2.2 × 108. Discussion: The Hg concentration in all analyzed samples was less than 0.50 and 1 ppm, which indicated that the Hg level was within acceptable limits according to Saudi Standards, Metrology and Quality Organisation (SASO) and the United States Food and Drug Administration (US FDA), respectively. On the other hand, the calculated margin of safety values for mercury exceeded the safe standard established by the WHO. The results derived from using hazard quotient (HQ) indices depict the potential carcinogenic health risk posed to consumers who employ red-colored lipsticks.

Validation of high-resolution continuum source flame atomic absorption spectrometry for determination of selected toxic and potential toxic metals in the decontamination process of wastewater discharged in natural receivers.

A new method based on high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) was validated for the determination of selected toxic and potentially toxic metals in wastewater resulting from mining activity. The results were compared with inductively coupled plasma optical emission spectrometry (ICP-OES). The HR-CS-FAAS method was characterized by detection limits in the range (µg L-1) 0.9(Mn)-33.6(Pb), better than ICP-OES for Cu, Fe, Ni, Co, Pb and Mn, and poorer for Cd, Zn and Cr. The Dunnett's and Tukey's statistical test showed that both methods were not affected by significant bias against certified value and between them. The recovery in HR-CS-FAAS method was in the range of 98-103% with relative extended uncertainty of 9-25%, and precision of 1.5-14.1%. The results indicated that the HR-CS-FAAS method is suitable for the determination of toxic and potentially toxic elements directly in filtered water samples without any chemical treatment.

Robust carbon quantum dots supported cobalt oxide composite particles prepared by hydrothermal process for green hydrogen generation via sodium borohydride hydrolysis

Carbon quantum dots (CQDs), a new class of carbon nanostructures with a particle size of 10 nm, exhibit important properties such as easy surface functionalization, low cost, chemical inertness, water solubility and low toxicity. In this study, an effective catalyst was synthesized using cobalt oxide (Co3O4) metal nanoparticles dispersed on CQD support material obtained from sucrose by hydrothermal method (Co3O4-SCQD-HT). The resulting catalyst system was used for effective hydrogen (H2) production from sodium borohydride (NaBH4) hydrolysis. Hydrogen generation rate (HGR) values of 7041, 18,426 and 27,555 mlmin−1gcat−1 were obtained with Co3O4-SCQD catalysts synthesized during the hydrothermal process with water, ethanol and methanol solvents, respectively. The HGR values of the catalysts obtained in ethanol and methanol medium provided an improvement of approximately 2.5 and 4 times, respectively, compared to the catalyst prepared in water medium. The activation energy for NaBH4 hydrolysis by Co3O4-SCQD-HT was 29.92 kJmol−1. Transmission Electron Microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), nitrogen adsorption/desorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Inductively coupled plasma optical emission spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS) analyses were used for the characterization study. The average particle size for the Co3O4-SCQD-HT nanocomposite is approximately 3.27 nm. The presence of carbon (C), oxygen(O), nitrogen (N) and cobalt (Co) atoms was confirmed by XPS and EDS analysis.

Employing a switching valve to automate external standard calibration in inductively coupled plasma optical emission spectrometry

The traditional external standard calibration method (EC) is automated and simplified using a four-port switching valve (SV4) and a multi-signal approach that enables the generation of several calibration points from a single calibration solution. The SV4-EC method is applied to inductively coupled plasma optical emission spectrometry (ICP-OES) and is based on gradient dilution taking place within the instrument's sample introduction tubing. Both the calibration solution and the samples are diluted by a blank solution containing an internal standard species. Forty-five dilution points are collected over time while the solutions are mixed. Instrument responses from the calibration solution are then plotted against those from the samples, and the slope of the calibration curve is used to determine the unknown analyte concentrations in the samples. The method is used to determine Ba, Co, Cr, Cu, Fe, Mn, Ni, V and Zn in coconut water, creek water, green tea, mouthwash, soft drink, vinegar, and vodka. Limits of detection are in the 0.0002–0.009 mg L−1 (n = 10) range, with precision on the order of 0.4 %–3 % RSD. Analyte percent recoveries from a 0.5 mg L−1 spike are in the ranges of 88.4 %–111 %, 88.9 %–111 %, and 88.0 %–111 % for EC, SV4-EC, and the internal-standard-corrected method (SV4-EC/Sc), respectively. No statistically significant difference is observed between EC and SV4-EC recoveries for any of the sample matrices evaluated. Comparable results between EC and SV4-EC were also found for the analysis of two certified reference materials, Bovine Liver and Oyster Tissue. Based on a single calibration solution, the SV4-EC method requires caution when preparing the calibration standard to minimize measurement bias.

Assessing Elemental Diversity in Edible-Podded Peas: A Comparative Study of Pisum sativum L. var. macrocarpon and var. saccharatum through Principal Component Analysis, Correlation, and Cluster Analysis

This study assessed eleven elements in 24 edible-podded peas, including sugar snap pea and snow pea genotypes aiming to identify promising parents for nutraceutical breeding. Elemental concentrations of pods (dry weight basis) were estimated through inductively coupled plasma-optical emission spectroscopy (ICP-OES). The ranges for these elements varied significantly, highlighting the diverse elemental profiles within the edible-podded pea genotypes. All the elements exhibited a high genotypic and phenotypic coefficient of variation along with considerable heritability and hereditary progress. Positive and significant correlations were recorded among all elements, suggesting the potential for simultaneous selection for these traits. Principal component analysis (PCA) revealed that the first two components accounted for 80.56% of the variation. Further, cluster analysis, based on Euclidean distance, grouped the 24 cultivars into two major clusters. Cluster I exhibited higher means for all estimated concentrations compared to Cluster II. Notably, Dwarf Grey Sugar and Arka Sampoorna from the snap pea group and PED-21-5 and Sugar Snappy from the sugar snap pea in Cluster II demonstrated superior elemental concentration in whole pods. The selected edible-podded pea genotypes serve as valuable genetic resources for new cultivar development, particularly in biofortification efforts targeting whole pod nutrient composition.

Valorization of ladle furnace slag and functional enhancement of post-adsorption materials

Carbonating metallurgical slags plays a pivotal role in achieving efficient mineral CO2 sequestration and waste valorization.This research introduces a novel integrated approach that combines the carbonation of Ladle Furnace Slag (LFS) with the simultaneous degradation of Methyl Orange (MO) in synthetic water. The comprehensive characterization of LFS was conducted using X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), Brunauer-Emmett-Teller (BET) analysis, and Scanning Electron Microscopy (SEM). The adsorption experiments reveal the high LSF capacity for MO degradation (149.25 mg/g) following pseudo-second-order kinetics (R2 = 0.99) and Langmuir isotherm (R2 = 0.98). The adsorption process was primarily governed by chemical and electrostatic interactions. Analysis of LFS-loaded MO indicated a reduction in Ca(OH)2phases, responsible for CO2mineralization and the formation of calcite (CaCO3). Furthermore, the study explored the reusability of LFS-MO composites through chemical and thermal modifications. Pyrolysis of carbonated LFS with KOH impregnation exhibited potential for regenerating Ca(OH)2phases, while thermal modification induced significant mineral and microstructural changes, creating new active sites at various temperatures. Additionally, the Fenton-like reaction followed by thermal modification resulted in a highly organized and microporous LFS structure with enhanced surface area and porosity. Moreover, modification with ZnSO4followed by thermal activation promoted the formation of ZnO nanoxides on the LFS surface. This research proposes an innovative carbonating approach for metallurgical slags and wastewater treatment, extending their utility and enhancing industrial sustainability. Carbonated LFS-MO composites hold promise for applications in construction, CO2capture, and wastewater treatment, thereby fostering sustainable industrial practices with ongoing research and development efforts.

Wild Mushrooms as a Source of Bioactive Compounds and Their Antioxidant Properties-Preliminary Studies.

Determination of active compounds by gas chromatography-mass spectrometry was carried out in addition to thermogravimetric determinations, quantitative determination of total polyphenols by spectrophotometry using Folin-Ciocalteu reagent, determination of antioxidant activity using 2,2-diphenyl-1-picryl hydrazyl radical (DPPH) and 2,2'-azino-di-[3-ethylbentiazoline sulphonated] (ATBS). In addition, spectrometric analysis of selected minerals and heavy metals was performed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The mushrooms analysed varied in terms of their bioactive constituents. They contained components with varying effects on human health, including fatty acids, oleamide, 1,2-dipalmitoylglycerol, (2-phenyl-1,3-dioxolan-4-yl)-methyl ester of oleic acid, deoxyspergualin, 2-methylenocholestan-3-ol, hexadecanoamide, isoallochan, 2,6-diaminopurine, and adenine. All contained polyphenols and varying amounts of minerals (calcium, magnesium, iron, zinc, potassium, phosphorus, sodium, copper, silicon and manganese) and exhibited antioxidant properties of varying potency. No exceedances of the permissible concentration of lead and cadmium were observed in any of them. All of the mushrooms studied can provide material for the extraction of various bioactive compounds with physiological effects. In addition, the presence of polyphenols and minerals, as well as antioxidant properties and the absence of exceeding the permissible concentration of heavy metals, indicate that these species could be interesting material in the design of foods with health-promoting properties, nutraceuticals or dietary supplements. However, the use of the fruiting bodies of these mushrooms requires mandatory toxicological and clinical studies.

Exploring the potential of chitosan from royal shrimp waste for elaboration of chitosan/bioglass biocomposite: Characterization and “in vitro” bioactivity

Exploiting royal shrimp waste to produce value-added biocomposites offers environmental and therapeutic benefits. This study proposes biocomposites based on chitosan and bioglass, using shrimp waste as the chitosan source. Chitin extraction and chitosan preparation were characterized using various analytical techniques. The waste composition revealed 24 % chitin, convertible to chitosan, with shells containing 77.33-ppm calcium. (X-ray diffraction) XRD analysis showed crystallinity index of 54.71 % for chitin and 49.14 % for chitosan. Thermal analysis indicated degradation rates of 326 °C and 322 °C, respectively. The degree of deacetylation of chitosan was 97.08 % determined by proton nuclear magnetic resonance (1H-NMR) analysis, with an intrinsic viscosity of 498 mL.g−1 and molar mass of 101,720 g/mol, showing improved solubility in 0.3 % acetic acid. Royal chitosan (CHR) was combined with bioglass (BG) via freeze-drying to create a CHR/BG biocomposite for bone surgery applications. The bioactivity of the CHR/BG was tested in simulated body fluid (SBF), revealing a biologically active apatite layer on its surface. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) analysis confirmed enhanced bioactivity of the CHR/BG compared to commercial chitosan. The CHR/BG biocomposite demonstrated excellent apatite formation, validated by Scanning Electron Microscopy (SEM), highlighting its potential in bone surgery.

Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples.

A sensitive and selective method for the detection of arsenic(iii) (As3+) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As3+ interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA. The aggregation of CS/AuNPs@TDA was accompanied with a change in color from red to bluish purple and a shift in surface plasmon resonance wavelength from 525 nm to 645 nm. The response for the detection of As3+ was linear at concentrations from 10 to 1000 μg L-1 with a limit of detection of 6.1 μg L-1. The method exhibited selectivity toward As3+ among various cations (As5+, Cu2+, Fe3+, Fe2+, Hg2+, Al3+, Cr3+, Cd2+, Co2+, Ni2+, Pb2+ and Zn2+) and anions (Br-, Cl-, F-, SO4 2-, NO3 - and PO4 2-). The CS/AuNPs@TDA nanoprobe was applied to detect As3+ in rice, drinking water and environmental water samples. The results were consistent with those obtained via inductively coupled plasma-optical emission spectrometry (ICP-OES). Satisfactory recoveries ranging from 88.22% to 105.74% (RSDs of 0.25-2.99%) were obtained from spiked samples.

Correlation between serum heavy metals and the risk of oral squamous cell carcinoma and oral potentially malignant disorders

Oral squamous cell carcinoma (OSCC) is a serious public health problem in various Asian countries, including Sri Lanka, and a combination of cultural practices, lifestyle factors, and genetic predispositions influences the incidence of these cancers. The examination of the connection between exposure to heavy metals and the probability of developing oral potentially malignant disorders (OPMD) and OSCC has been limited in its scope, and the overall consequences of such exposure remain largely unknown. This study aims to clarify the link between serum levels of heavy metals and the risk of OSCC and OPMD. The concentrations of seven heavy metals—namely, arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), and zinc (Zn)—were analyzed in serum samples from 60 cases and 15 controls in the Sri Lankan cohort. The Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) was used for the analysis. Subsequently, the data underwent statistical evaluation via the Kruskal–Wallis H test, using the Statistical Package for Social Sciences (SPSS) version 28 software, with a confidence interval set at 95%. A p-value less than 0.05 was considered statistically significant. The cohort consisted of 48 men and 27 women, with 15 patients each diagnosed with OSCC, OSF, OLK, and OLP, and 15 healthy controls. The study used the Kruskal–Wallis Test to compare metal concentrations across groups, finding significant differences for all metals except As and Pb. Significant associations were observed between age, past medical history, drug history, gender, smoking, alcohol consumption, and betel chewing. The Spearman Correlation test showed significant correlations between the concentrations of Cr, Co, Cu, As, and Zn and the presence of cancer/precancer conditions. The study’s findings suggest that heavy metal contamination may be linked to the development of OSCC and precancerous conditions. When comparing OSCC and OPMD cases with controls, the serum concentrations of As and Pb did not differ significantly. However, Cd, Cr, Co, Cu, and Zn exhibited significantly higher concentrations among cases compared to controls (p < 0.05). This study observed significant variations in the levels of these five heavy metals among cancerous (OSCC), premalignant (OPMD), and healthy tissues, suggesting a potential role in the progression of malignancies. These findings underscore the importance of environmental pollution in this specific context.

Adsorption Dynamics of Disodium Octaborate Tetrahydrate on Clay Minerals: Implications for Construction Wood Protection.

The wood preservative disodium octaborate tetrahydrate (DOT) migration is studied in clay. Using boron analysis by inductively coupled plasma optical emission spectroscopy (ICP-OES), DOT spatial and temporal dynamics are surveyed to show how DOT permeates into the wood and the clay using concentration profiles as a function of depth, initial wood moisture, and direction of filling. Atomic force microscopy and chemical imaging using photoinduced force microscopy are used to show the morphology of the wood samples and the distribution of DOT on their surface. ICP-OES results show that the average DOT concentration in the wood samples is originally 0.8 and 1.5 wt% in the bulk and at the surface, respectively. Conditioning of the wood to a moisture content of 19% in a climatic chamber reduces DOT concentration by 8% for the fir and 17% for the spruce. After one week of contact with the clays, the results showed a rapid decrease of 25-40% in DOT concentration in wood. On longer periods (5 months), the spruce shows a tendency to reabsorb the DOT from the clay and the DOT migration stabilizes at 20%. These results contribute to defining the dosage of DOT when the wood is exposed to clay.

Determination Ca, Cu, Fe, Mn, and Zn release from food in simple gastrointestinal extraction test

In this study, by conducting simulated in vitro digestion experiments on samples, the extraction rates of several essential metal elements in some common food ingredients were determined to guide a rational and balanced diet. At the same time, taking vegetables as an example, the research investigated the impact of food preprocessing on the extraction rates of metal elements within them, demonstrating that the influence of heat treatment varies for different element extraction rates. A wet digestion system using nitric acid-hydrogen peroxide was established for seafood and vegetable samples, and an analytical method for determining Ca, Cu, Fe, Mn and Zn using inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. The detection limits of the method ranged from 0.0003 mg L−1 to 0.1567 mg L−1, with RSDs between 0.004% and 7.161%. The measured contents of several important metal elements in standard substances were largely consistent with national standards, confirming the accuracy and precision of the method. Based on wet digestion, the contents of various metal elements in simulated digestive fluids were determined. The detection limits for the simulated digestion method ranged from 0.0005 mg L−1 to 0.0077 mg L−1, with RSDs between 0.001% and 8.839%, verifying the precision of the method. Consequently, the extraction rates of metal elements in the two types of samples were obtained, leading to the conclusion that vegetable samples are more easily digested compared to seafood, releasing their metal elements. Moreover, the extraction rates of different elements vary within the same type of sample, and the extraction rates of the same element also differ across different samples. For dried fruit samples, a dry ashing digestion system was established, and an analytical method for determining Ca, Cu, Fe, Mn and Zn using ICP was developed. The detection limits of this method ranged from 0.0003 mg L−1 to 0.0073 mg L−1, with RSDs between 0.001% and 1.076%, and the spiked recovery rates were between 85.43% and 105.96%, confirming the accuracy and precision of the method. Based on dry ashing digestion, the contents of various metal elements in simulated digestive fluids were measured, which led to the determination of the element extraction rates. Among these, the extraction rates for Ca, Cu, and Mn were relatively high.

Re-designing nano-silver technology exploiting one-pot hydroxyethyl cellulose-driven green synthesis.

Re-designing existing nano-silver technologies to optimize efficacy and sustainability has a tangible impact on preventing infections and limiting the spread of pathogenic microorganisms. Advancements in manufacturing processes could lead to more cost-effective and scalable production methods, making nano-silver-based antimicrobial products more accessible in various applications, such as medical devices, textiles, and water purification systems. In this paper, we present a new, versatile, and eco-friendly one-pot process for preparing silver nanoparticles (AgNPs) at room temperature by using a quaternary ammonium salt of hydroxyethyl cellulose (HEC), a green ingredient, acting as a capping and reducing agent. The resulting nano-hybrid phase, AgHEC, consists of AgNPs embedded into a hydrogel matrix with a tunable viscosity depending on the conversion grade, from ions to nanoparticles, and on the pH. To investigate the synthesis kinetics, we monitored the reaction progress within the first 24h by analyzing the obtained NPs in terms of particle size (dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM)), Z-potential (ELS), surface plasmon resonance (UV-VIS), crystallographic phase (XRD), viscosity, and reaction yield (inductively coupled plasma-optical emission spectrometry (ICP-OES)). To explore the design space associated with AgHEC synthesis, we prepared a set of sample variants by changing two independent key parameters that affect nucleation and growth steps, thereby impacting the physicochemical properties and the investigated antimicrobial activity. One of the identified design alternatives pointed out an improved antimicrobial activity in the suspension, which was confirmed after application as a coating on nonwoven cellulose fabrics. This enhancement was attributed to a lower particle size distribution and a positive synergistic effect with the HEC matrix.

Inorganic Characterization of Feeds Based on Processed Animal Protein Feeds.

The potential of utilizing inorganic constituents in processed animal proteins (PAPs) for species identification in animal feeds was investigated, with the aim of using these constituents to ensure the quality and authenticity of the products. This study aimed to quantify the inorganic content across various PAP species and assess whether inorganic analysis could effectively differentiate between PAP species, ultimately aiding in the identification of PAP fractions in animal feeds. Four types of PAPs, namely bovine, swine, poultry, and fish-based, were analyzed and compared to others made up of feathers of vegetal-based feed. Also, three insect-based PAPs (Cricket, Silkworm, Flour Moth) were considered in this study to evaluate the differences in terms of the nutrients present in this type of feed. Ionic chromatography (IC) was used to reveal the concentrations of NO3-, NO2, Cl-, and SO42-, and inductively coupled plasma optical emission spectroscopy (ICP-OES) to detect Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Si, Sr, Ti, and Zn. The application of multivariate chemometric techniques to the experimental results allowed us to determine the identification capability of the inorganic composition to identify correlations among the variables and to reveal similarities and differences among the different species. The results show the possibility of using this component for discriminating between different PAPS; in particular, fish PAPs are high in Cd, Sr, Na, and Mg content; swine PAPs have lower metal content due to high fat; feathers and vegetal feed have similar Al, Si, and Ni, but feathers are higher in Fe and Zn; and insect PATs have nutrient levels comparable to PAPs of other origins but are very high in Zn, Cu, and K.

Correction for partial volume averaging in the quantification of radiopaque nanomaterial-embedded resorbable polymers

Resorbable inferior vena cava (IVC) filters require embedded contrast for image-guided placement and integrity monitoring. We calculated correction factors to account for partial volume averaging of thin nanoparticle (NP)-embedded materials, accounting for object and slice thicknesses, background signal, and nanoparticle concentration. We used phantoms containing polycaprolactone disks embedded with bismuth (Bi) or ytterbium (Yb): 0.4- to 1.2-mm-thick disks of 20 mg ml−1 NPs (thickness phantom), 0.4-mm-thick disks of 0–20 mg ml−1 NPs in 2 mg ml−1 iodine (concentration phantom), and 20 mg ml−1 NPs in 0.4-mm-thick disks in 0–10 mg ml−1 iodine (background phantom). Phantoms were scanned on a dual-source CT with 80, 90, 100, and 150 kVp with tin filtration and reconstructed at 1.0- to 1.5-mm slice thickness with a 0.1-mm interval. Following scanning, disks were processed for inductively coupled plasma optical emission spectrometry (ICP-OES) to determine NP concentration. Mean and maximum CT numbers (HU) of all disks were measured over a 0.5-cm2 area for each kVp. HU was converted to concentration using previously measured calibrations. Concentration measurements were corrected for partial volume averaging by subtracting residual slice background and extrapolating disk thickness to both nominal and measured slice sensitivity profiles (SSP, mm). Slice thickness to agreement (STTA, mm) was calculated by replacing the CT-derived concentrations with ICP-OES measurements and solving for thickness. Slice thickness correction factors improved agreement with ICP-OES for all measured data. Yb corrections resulted in lower STTA than Bi corrections in the concentration phantom (1.01 versus 1.31 STTA/SSP, where 1.0 is perfect agreement), phantoms with varying thickness (1.30 versus 1.87 STTA/SSP), and similar ratio in phantoms with varying background iodine concentration (1.34 versus 1.35 STTA/SSP). All measured concentrations correlated strongly with ICP-OES and all corrections for partial volume averaging increased agreement with ICP-OES concentration, demonstrating potential for monitoring the integrity of thin IVC resorbable filters with CT.

Towards a further understanding of cement hydration at the early-age stage in the presence of hydrophobic silane IBTEO

Hydrophobic silane hinders internal water penetration by tuning the surface wettability of concrete. The presence of hydrophobic groups in the silane was observed to adversely influence early cement hydration. This study employs a combination of calorimetry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), inductively coupled plasma optical emission spectroscopy (ICP-OES), and total organic carbon (TOC) analysis to investigate the effects of hydrophobic isobutyl-triethoxysilane (IBTEO) on cement hydration. The results demonstrate that the silicate reaction integral to cement hydration slows as the concentration of hydrophobic silane increases. The nucleation of hydration products, such as calcium silicate hydrate (C–S–H), exhibits heightened sensitivity to the presence of hydrophobic silane. Although hydrophobic silane marginally impacts the initial dissolution of cement particles, it significantly decreases ion dissolution after 60 min. This reduction in hydration rate and the consequent delay in the emergence of the second exothermic peaks in hydration are attributable to the negative impact of the hydrophobic functional groups on the silicate reactions and the formation of hydrogen bonds. These findings offer new perspectives on the impact of hydrophobic silanes on cement hydration, potentially guiding the development of silane-cement systems towards enhanced superhydrophobicity and improved permeability.

Novel Microwave Assisted-Hydrogen Peroxide Digestion of Coal and Fuel Oils Using Methionine as a Capping Reagent for the Determination of Mercury by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES)

A novel analytical method was developed for quantifying total mercury in fuel oils using methionine as a capping reagent. Methionine was added to fuel and standard solutions as a preserving agent before microwave-assisted hydrogen peroxide digestion (MW-AHPD). To the best of our knowledge, it is the first-time methionine was used as a capping reagent for the total determination of mercury in fuel oils using ICP-OES with a pneumatic nebulizer. Multivariate optimization tools (two-level half factorial and central composite design) were used to investigate the most influential parameters of the MW-AHPD method. The best conditions were 0.1 g sample mass, 5 mol L−1 [H2O2], 5. 95 mol L−1 [methionine], 36 min and 200 °C with accepted trueness (93–107%) and precision (1.94%). The developed MW-AHPD procedure provided a coefficient of determination (R2) of 0.9989, limit of detection (LOD) of 0.25 µg L−1 and limit of quantification (LOQ) of 0.8 µg L−1. The newly developed MW-AHPD procedure was validated using hydride generation-ICP-OES and there was no statistical difference at 95% confidence level between the newly developed method and the standard protocol. Therefore, the newly developed MW-AHPD procedure was applied with coal, crude oil, gasoline, diesel oil, and kerosine samples and the concentration levels were from 0.876 ± 0.023 to 0.938 ± 0.082 µgg−1, 0.383 ± 0.043 to 0.506 ± 105 µgg−1, 0.306 ± 0.010 to 0.390 ± 0035 µgg−1, 0.360 ± 0.003 to 0.431 ± 0.001 µgg−1 and < DL, respectively.