Inductively Coupled Plasma Optical Emission Spectroscopy Analysis Research Articles

Biosorption of copper, nickel, and manganese as well as the production of metal nanoparticles by Bacillus species isolated from soils contaminated with electronic wastes.

Improper electronic waste management in the world especially in developing countries such as Iran has resulted in environmental pollution. Copper, nickel, and manganese are from the most concerned soil contaminating heavy metals which found in many electronic devices that are not properly processed. The aim of this study was to investigate the biological removal of copper, nickel, and manganese by Bacillus species isolated from a landfill of electronic waste (Zainal Pass hills located in Isfahan, Iran) which is the and to produce nanoparticles from the studied metals by the isolated bacteria. The amounts of copper, nickel, and manganese in the soil was measured as 1.9 × 104 mg/kg, 0.011 × 104 mg/kg and 0.013 × 104 mg/kg, respectively based on ICP-OES analysis, which was significantly higher than normal (0.02 mg/kg, 0.05 mg/kg, and 2 mg/kg, respectively. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of metals on the bacterial isolates was determined. The biosorption of metals by the bacteria was evaluated by inductively coupled plasma optical emission spectroscopy (ICP-OES). The metal nanoparticles were synthetized utilizing the isolates in culture media containing the heavy metals with the concentrations to which the isolates had shown resistance. X ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) were used for the evaluation of the fabrication of the produced metal nanoparticles. Based on the findings of this study, a total of 15 bacterial isolates were obtained from the soil samples. The obtained MICs of copper, nickel, and manganese on the isolates were 40-300 mM, 4-10 mM, and 60-120 mM, respectively. The most resistant isolates to copper were FM1 and FM2 which were able to bio-remove 79.81% and 68.69% of the metal, respectively. FM4 and FM5 were respectively the most resistant isolate to nickel and manganese and were able to bio-remove 86.74% and 91.96% of the metals, respectively. FM1, FM2, FM4, and FM5 was molecularly identified as Bacillus cereus, Bacillus thuringiensis, Bacillus paramycoides, and Bacillus wiedmannii, respectively. The results of XRD, SEM and EDS showed conversion of the copper and manganese into spherical and oval nanoparticles with the approximate sizes of 20-40 nm. Due to the fact that the novel strains in this study showed high resistance to copper, nickel, and manganese and high adsorption of the metals, they can be used in the future, as suitable strains for the bio-removal of these metals from electronic and other industrial wastes.

Extended Spectrum Beta-Lactamase Expressing <i>Chromobacterium</i> Sp. Dyh27s2016 Strain is Capable of Metal Leaching in Electronic Waste

Printed circuit boards (PCBs) contain many precious and hazardous metals, and the disposal of a large number of electronic wastes (e-waste) has been a serious environmental concern. The conventional metallurgy methods used to recover metals from e-wastes require higher energy expenditure besides contributing to significant environmental pollution. This necessitated an alternative approach, such as using cyanogenic and other environmental bacteria to recover metals from e-waste. Hence, the current study is aimed to explore the feasibility of Chromobacterium sp. Dyh27s2016 strain in mobilising metals from e-waste. A two-step bioleaching process was employed with the ATCC culture Chromobacteriumviolecium Bergonzini (12472TM) used as a control. The metal content in the supernatant was analysed using the inductively coupled plasma - optical emission spectrometry (ICP-OES) technique. Meanwhile, the metal concentration in PCBs was also assessed using the acid reflux method followed by the ICP-OES analysis. Besides, the Chromobacterium sp. Dyh27s2016 strain was also assessed for the beta-lactam antibiotics resistance and the gene expression for extended spectrum beta-lactamase (ESBL). It was observed that Chromobacterium sp. Dyh27s2016 strain mobilises 80, 94, 52 and 56% of Cu, Fe, Zn and Ag respectively from e-waste. However, this strain was found resistant to penicillin G sodium, ampicillin sodium and ticarcillin disodium but susceptible to cefotaxime sodium antibiotics. The molecular analysis showed that this strain possessed the ESBL genes, TEM and CTX-M. The findings from this study enable potential industrial applications for recycling electronic trash using Chromobacterium Dyh27s2016 strains in future.

Insights about inductively coupled plasma optical emission spectroscopy interferences of major rare earth elements in complex e-waste feeds

The advent of rare earth elements (REEs) with optoelectronic properties has shifted the technology paradigm from digital to a smart and hybrid world. Their substantial uses also resulted in a large piling up of e-waste. Therefore, e-waste is now a lucrative recycling target for the recovery of such critical raw materials. Their recycling from e-waste is often challenged by dilute metal concentration, complex composition, and difficult chemical characterisation. Generally, the characterisation of e-waste involves elemental determination techniques, such as inductively coupled plasma optical emission spectroscopy (ICP-OES) or inductively coupled plasma mass spectrometry (ICP-MS). ICP-OES is attractive for a recycling or research sector because it has a higher matrix tolerance and lower cost than ICP-MS. In this work, the intensity at 445 line positions measured by an ICP-OES instrument was compiled in a 2D diagram to map interferences by 27 prominent lines from 9 REEs. The second diagram shows the impact at 230 neighbouring line positions measured in each of, in total, 17 (i.e., 9 REEs and 8 non-REEs) single-standard solutions in terms of the concentration of the element type affected. The spectral interference correction algorithm proposed here had been developed by us for a recycling process to obtain pure Y, Eu, and Tb from fluorescent powder (FP) in spent lamps. The ICP-OES analysis and spectral interference correction approach presented here can be applied to any element and e-waste type. To underline this, the paper gives examples for elements in dissolved FP and surrogate NdFeB magnet samples.

Evaluation and analysis of perlite and municipal wastewater sludge (biosolids) from three wastewater treatment plants in East Texas, USA.

Municipal wastewater sludge (also known as biosolids) is produced in large quantities from wastewater treatment plants (WWTPs). Traditionally, analyses of biosolids revealed the presence of inorganic (including metals) and organic contaminants which pose health concerns to man and the environment. This study investigated physical-chemical parameters and comparative element concentrations (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Ni, P, Pb, S, Se, Zn, V, Na, S, and P) in biosolids and composted wastewater sludge (CWS) from Nacogdoches Wastewater Treatment Plant (NWWTP), Lufkin Wastewater Treatment Plant (LWWTP), and Angelina-Neches Compost Facility (NCF) in East Texas (USA). In addition, concentrations in perlite, a hydroponic material, were determined via Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy/energy dispersive X-ray diffraction (SEM/EDX), inductively coupled plasma-optical emission spectroscopy (ICP-OES), X-ray diffraction (XRD)), and thermogravimetric (TGA) analysis. Via ICP-OES analysis, metal concentrations in biosolid samples were similar. Macroelement amounts followed the order: NWWS ≈ LWWS > NCS > perlite. Notably, concentrations in biosolids, CWS, and perlite are below recommended USEPA and WHO maximum ceiling levels. The pH of biosolid samples was determined between 5.33 and 6.74. The weight loses of 6-19% wt at ~ 300-700 ℃ are attributed to volatile compounds and inorganic metal oxides. From environmental and circular economy perspectives, this study shows biosolids to be safe, and potential recycling can be encouraged for use in soil amendments. This finding could find impetus to design of much better WWTPs which improve removal efficiencies and encourage recycling of biosolids.

A Comparison of Methods for the Characterisation of Waste-Printed Circuit Boards

Electronic waste is a growing waste stream globally. With 54.6 million tons generated in 2019 worldwide and with an estimated value of USD 57 billion, it is often referred to as an urban mine. Printed circuit boards (PCBs) are a major component of electronic waste and are increasingly considered as a secondary resource for value recovery due to their high precious and base metals content. PCBs are highly heterogeneous and can vary significantly in composition depending on the original function. Currently, there are no standard methods for the characterisation of PCBs that could provide information relevant to value recovery operations. In this study, two pre-treatments, smelting and ashing of PCB samples, were investigated to determine the effect on PCB characterisation. In addition, to determine the effect of particle size and element-specific effects on the characterisation of PCBs, samples were processed using four different analytical methods. These included multi-acid digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) analysis, nitric acid digestion followed by X-ray fluorescence (XRF) analysis, multi-acid digestion followed by fusion digestion and analysis using ICP-OES, and microwave-assisted multi-acid digestion followed by ICP-OES analysis. In addition, a mixed-metal standard was created to serve as a reference material to determine the accuracy of the various analytical methods. Smelting and ashing were examined as potential pre-treatments before analytical characterisation. Smelting was found to reduce the accuracy of further analysis due to the volatilisation of some metal species at high temperatures. Ashing was found to be a viable pre-treatment. Of the four analytical methods, microwave-assisted multi-acid digestion offered the most precision and accuracy. It was found that the selection of analytical methods can significantly affect the accuracy of the observed metal content of PCBs, highlighting the need for a standardised method and the use of certified reference material.

Simultaneous Determination of REEs in Coal Samples Using the Combination of Microwave-Assisted Ashing and Ultrasound-Assisted Extraction Methods Followed by ICP-OES Analysis

The world during the COVID-19 pandemic has led to extensive use of virtual activities by means of electronic devices, which are made up of rare earth elements (REEs). This means that quantitative knowledge of REEs in various resources is crucial for the development of effective recovery methods. Therefore, this report describes a simple microwave assisted ashing followed by ultrasound-assisted extraction (MAA-UAE) for quantitative determination of REEs in coal samples using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Firstly, coal samples were ashed at 55 °C for 4.5 h to form white ashes, which were then treated with dilute HNO3 acid under ultrasonication to enhance the extraction of REEs. The quantitative recoveries (86–120%) of REEs were obtained when 1 mol L−1, 0.1 g, 40 °C, 20 min, and high frequency were applied for [HNO3], sample mass, ultrasonic bath temperature, extraction time, and ultrasonic bath frequency, respectively. The method detection limits of the proposed MAA-UAE method were between 0.0075 and 0.59 µg g−1 with satisfactory precision (<5%). The concentration levels of REEs in South African coals ranged from 1.4 to 105 µg g−1, suggesting that this coal can be a resource for REEs.

Plastic film and organic mulching increases rhizosphere microbial population, plant growth, and mineral uptake in low input grown tomato in the northwestern region of India

Crop management determinants that manipulate population, diversity and function of soil microbiome are crucial for managing plant health and soil quality, nutrients cycling, ecosystem functioning, and plant-soil feedback. Herein, the objectives of the present preliminary investigation were to assess the impact of plastic film (black and silver) and organic (wheat straw) mulching on the different rhizosphere microbial population, plant growth, and mineral uptake in tomato crop. The measurement of rhizosphere microbial population and plant growth attributes was performed at the vegetative and reproductive growth stages of the tomato crop, while, mineral uptake analysis was carried out at the vegetative stage using the inductively coupled plasma optical emission spectrometry (ICP-OES). The result of experiments revealed that soil mulching favored microbial abundance in the crop rhizosphere, improved plant growth parameters and mineral uptake in tomato plants. The highest bacterial (6.75 ± 0.16 log10 colony-forming units per gram of soil (CFUg−1), and phosphorous solubilizing organisms (5.47 ± 0.02 log10 CFUg−1) population was found in silver mulch while wheat straw (as organic mulch) resulted in the higher fungal (4.64 ± 0.04 log10 CFUg−1), actinomycetes (5.68 ± 0.06 log10 CFUg−1) and rhizobial count (3.77 ± 0.07 log10 CFUg−1) during the vegetative growth. Consistently, the rhizosphere microbial population at the fruiting stage was also found higher in either colored plastic film or organic mulch treatment. Soil mulching also led to the substantial improvement in the plants shoot length, shoot girth and the number of secondary branches both at the vegetative and fruiting stage. ICP-OES analysis of mulched plant revealed the better mineral uptake in different parts of plants. The highest concentration for P (4535.67 ± 92.87 mgkg−1), K (11933.33 ± 338.35 mgkg−1), Mg (10263.33 ± 63.86 mg kg−1) and micronutrients uptake values for Fe (1167.67 ± 16.14 mg kg−1), Mn (133.83 ± 2.15 mg kg−1), and Cu (40.11 ± 0.87 mg kg−1) were observed in the silver film mulch treatment. Likewise, tomatoes from soil mulched conditions also recorded the highest uptake of the analyzed mineral nutrients. The present study revealed that soil mulching could be an effective technique for favorably altering beneficial soil microflora and enhancing mineral uptake in crop plants and thus for improving soil quality and productivity in a sustainable manner.

Insight into the provenance and clustering of Middle Chalcolithic Ceramics from Chaharmahal-Bakhtiari, Iran: Using petrographic and ICP-OES analysis

The present study investigated the similarities in appearance and style from the Middle Chalcolithic Ceramics (MCC) (ca. 5000–3800 cal. B.C.E.) in the Chaharmahal-Bakhtiari region, Iran, to those from Khuzestan and Fars. A multi-analytical approach was used to determine whether the resemblance of painted buff ware from Chaharmahal-Bakhtiari could be distinguished from the two neighboring regions based upon their stylistic preferences, technologies, and subsequent local production or not. A total number of 32 sherds, collected from the surface of the Middle Chalcolithic (MC) sites of the Chaharmahal-Bakhtiari, Khuzestan, and Fars regions, were examined petrographically. Ten of these underwent further geochemical fingerprinting via inductively coupled plasma-optical emission spectrometry (ICP-OES). The study could obtain details on manufacturing technologies or go beyond general descriptions of fabric groups and their relationships towards geological formations in the area concerned to determine their provenance. This analysis was also determined whether this kind of ceramic was native or had been imported into the area by nomads. Based on the results, ceramics had been locally produced based upon their chemical fingerprint. Moreover, metric analyses demonstrated the dispersed nature of the ceramic industry in the Chaharmahal-Bakhtiari region during the MC Age, suggesting that household production, influenced by the Susiana and Tall-i Bakün cultures was much more dominant.

Development of Membrane-Based Inverted Liquid-Liquid Extraction for the Simultaneous Extraction of Eight Metals in Seawater before ICP-OES Analysis.

In this work, we developed an extraction technique that can handle simple as well as complex matrixed liquid (aqueous) samples. In the standard liquid–liquid extraction, it is quite challenging to deal with complex liquid samples as they may complicate the process of phase separation and may lead to the formation of multiple layers. To resolve this issue, we have proposed a simple but unique idea that suggests the packing of the liquid samples inside a porous membrane bag. The edges of the membrane bag can be sealed using an electrical heat-sealer. The porous membrane bag filled with the liquid sample was immersed in an extraction solvent, and the extraction process was assisted by mechanical shaking. In order to demonstrate the proof of concept, a method was developed for the extraction of metals from seawater samples. The pH-adjusted sample, along with the complexing reagent, was packed inside the porous membrane bag, and the chelated complex was then extracted by immersing and shaking the bag inside the organic solvent. The solvent was then evaporated, and the chelated complex was dissolved/digested in acid with the aid of the heat. The final extract was subjected to Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analysis. The proposed method was used for extraction of eight metals (Cd, Co, Cu, Mo, Ni, Pb, V and Zn) from seawater samples and good extraction recoveries (75–94%) were obtained.

Effects of microwave pre-treatment on the flotation of ilmenite and titanaugite

The selective separation of titanium-containing minerals is industrially important. Microwave irradiation pre-treatment can be used to modify the surface properties of minerals to promote selective flotation. However, the effects of MW treatment on titanium-containing minerals is not well understood. Therefore, in this study, we investigated the effects of microwave treatment on the flotation behaviour of ilmenite and titanaugite in a mixture of these minerals. The effects of this pre-treatment method were investigated by various techniques, including flotation tests, scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), zeta potential measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FTIR) spectroscopy. The flotation tests results reveal that, under the optimum microwave conditions (800 W, 450 s), microwave irradiation has a remarkable effect on the flotation of ilmenite but no significant effect on the floatability of titanaugite at pH 6.0. The results of the SEM and ICP-OES analyses indicate that microwave irradiation promotes the dissolution of Ca2+ and Mg2+ ions from the titanaugite surface, whereas the dissolution of these ions from ilmenite is limited. Further, the zeta potential of the microwave-irradiated ilmenite shifted toward negative values, and the isoelectric point shifted from pH 4.9 to pH ~1.9. In addition, the XPS results reveal that microwave irradiation facilitates the conversion of Fe2+ to Fe3+ on the mineral surfaces. The FTIR spectra and zeta potential values indicate that microwave irradiation can enhance the chemical adsorption of oleate ions on the surface of the ilmenite. After microwave irradiation, the effects of both the dissolution of Ca2+ and Mg2+ ions and the oxidation of Fe2+ to Fe3+, the floatability of ilmenite was significantly improved, whereas that of titanaugite was not changed significantly.

ICH Q3D based elemental impurities study in liquid pharmaceutical dosage form with high daily intake – comparative analysis by ICP-OES and ICP-MS

Guideline for Elemental Impurities-Q3D of the International Conference on Harmonisation represents a new paradigm in the control of elemental impurities (EIs) in pharmaceuticals. It changes the approach toward control of EIs from the historical ‘heavy metals test’, to a scientific-based risk assessment and testing by modern analytical instrumentation such as inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS). Management of EIs related to all finished drug products must be implemented in strict compliance with the regulatory requirements of pharmaceutical industry due to their quality and safety concerns. Testing for presence of EIs from Class 1 and Class 2a in methadone hydrochloride 1 mg/ml oral solution with recommended daily intake of 150 mg methadone hydrochloride was initially performed on ICP-OES using in-house validated method according to the requirements of pharmacopoeias, in line with Q3D. During the procedure, it became apparent that ICP-OES has its own limitations, especially when it comes to testing arsenic and lead in low concentrations. ICP-MS in-house validated method was developed and employed for determination of trace concentrations of arsenic and lead, providing resourceful information that were compared and correlated to the data obtained by ICP-OES analysis. Sample preparation using microwave digestion technique was applied for the analyses by both techniques. Although the applied ICP-OES in-house method is suitable for determination of Hg, Cd, Co, V, and Ni, more sensitive technique such as ICP-MS is required for accurate determination of As and Pb concerning pharmaceuticals with high daily intakes.

Multimetal Resistant, Alkalitolerant Bacteria Isolated from Serpentinizing Fluid-Associated Sediments and Acid Mine Drainage in the Zambales Ophiolite, the Philippines

Weathering in ophiolitic exposure settings often produces fluids and sediments that have elevated concentrations of various toxic heavy metals such as chromium, nickel, cobalt, copper, and zinc. Microorganisms inhabiting these environments (e.g., serpentinite soils or sediments) are likely adapted to tolerate these metals along with other physicochemical extremes. The purpose of this study is to isolate bacteria capable of tolerating extremely high concentrations of multiple metals and to assess the various tolerance mechanisms exhibited by different organisms. Sediment samples for microbial culturing were collected from Manleluag Spring National Park and Barlo Mine located on the island of Luzon, the Philippines. Luria-Bertani (LB) agar medium was supplemented with increasing concentrations of five trace elements – Cu, Cr, Co, Ni, and Zn. Over 20 isolates were obtained from media with concentrations ranging from 25 mg/L to 400 mg/L of each metal. Most isolates were identified as belonging to the genus Bacillus. Adaptation mechanisms, including potential biomineralization, were considered for select strains using inductively coupled plasma optical emission spectroscopy (ICP-OES), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). ICP-OES analysis suggests that the primary resistance mechanism used by most isolates is cellular efflux, although it was determined that some organisms were able to reduce aqueous Cu concentration by up to 40%. Most strains exhibited growth at pH 12, demonstrating that alkalitolerant, highly metal resistant organisms are found in these ophiolite-associated environments. These organisms may be exploited for bioremediation, secondary metabolite production, and other industrial applications.

Effect of exposure time of an acidic beverage on the microhardness, mineral weight, and rate of calcium and phosphate ion release of human enamel

Aims and Objectives: The aim of this study was to investigate the effect of exposure times of Coca Cola on enamel’s microhardness, mineral weight, and rate of calcium and phosphate ions discharging from it. Materials and Methods: Thirty-two enamel blocks were randomly divided into four groups and exposed to 10mL of their respective solution daily for 7 days, with each group containing eight specimens: Group 1 (enamel blocks exposed to artificial saliva, control group), group 2 (enamel blocks exposed to Coca Cola for 5 minutes), group 3 (enamel blocks exposed to Coca Cola for 10 minutes), and group 4 (enamel blocks exposed to Coca Cola for 30 minutes). Microhardness data (Vickers hardness number [VHN]) and mineral weight were calculated at baseline (sound enamel) and postexposure to Coca Cola. Inductively coupled plasma–optical emission spectrometry (ICP-OES) was utilized to study calcium and phosphate ion percolation from enamel surfaces. Results: Decrease in VHN was directly proportional to exposure time for all experimental groups. Comparison of baseline and postexposure values between control and experimental groups was statistically significant (P < 0.05). Mineral weight of enamel blocks decreased as the exposure time increased for all experimental groups. ICP-OES analysis revealed linear relationship between release of calcium and phosphate ions at 5 and 10 minutes, but at 30 minutes, a decrease in concentration of both ions was observed. Conclusion: The microhardness and mineral weight of enamel decreased linearly with exposure time. The release of calcium and phosphate ions from enamel increased initially but gradually decreased as the exposure time increased.

Preparation, characterization and in vitro biological study of silk fiber/methylcellulose composite for bone tissue engineering applications

In the present work, silk fiber (SF) and methylcellulose (MC) composites were fabricated by solvent casting method and characterized in detail. The interactions between SF/MC composites were studied in detail by Fourier transform infrared (FT-IR) spectroscopy and powder X-ray diffraction (XRD). The surface morphology and thermal stability were studied. Viscosity, thickness, folding endurance, tensile strength and antioxidant activity were analyzed for different ratios of SF/MC composite. Antimicrobial activity, in vitro biomimetic mineralization, hemocompatibility and cell viability of the SF/MC composite were studied. The deposition of calcium and phosphorus ions from simulated body fluid (SBF) onto SF/MC composite surface was evidenced from XRD, FT-IR and SEM–EDS. Inductively coupled plasma-optical emission spectrometry analysis (ICP-OES) was utilized to analyze leaching of Ca and P ions from the SBF. Hemolytic assay proves that the composites were compatible with blood and hemolytic ratio is found to be less than 5%. The MTT assay test against MG-63 suggests that the SF/MC composites are promising biomaterials for bone tissue engineering applications.

Classification of organic olives based on chemometric analysis of elemental data

The aim of this study was to discriminate organic from conventional olive samples based on the levels of macro and trace elements, combined with chemometric techniques. Ten elements (Na, K, Ca, Fe, Mg, Cu, Zn, Se, S and P) were determined in organic (n = 30) and conventional (n = 30) olive samples by inductively coupled plasma optical emission spectrometry analysis (ICP-OES). The classification of samples was performed by using a well-known chemometric techniques, linear discriminant analysis (LDA), partial least square-discriminant analysis (PLS-DA), support vector machine-discriminant analysis (SVM-DA), k-nearest neighbors (k-NN) and random forest (RF). The k-NN technique showed the best performance in discriminating organic from conventional samples (Accuracy: 94%) using all chemical variables. After variable reduction, an accuracy of 83% was found by using only the elements K and P. The use of a fingerprint based on multielemental levels associated with classification chemometric techniques may be used as a simple method to authenticate organic olive samples.

The Characterization of the Selected Trees Damaged During Severe Weather Episode on the Mountain Avala (Serbia) Using IR Thermography, ICP-OES, and Microbiological Analysis

Selected plants of white fir and lime, damaged during severe weather episode on the mountain Avala (Serbia) in summer 2014, were analyzed and characterized (including their spatial soil samples) by inductively coupled plasma optical emission spectroscopy (ICP-OES), infrared (IR) thermography, and microbiological method such as enumeration of cultivable microorganisms. The results obtained from chemical and microbiological analyses provided valuable information on possible biotic and abiotic stressors such as soil fungi and heavy metals, which could affect the health status of trees, while IR thermography visualized this status in a very specific and effective way. The results of ICP-OES analysis clearly showed that the investigated heavy metals (Cu, Zn, Pb, As, Cd, and Ni) were less likely crucial factors responsible for ruined health status of damaged trees. The role of soil fungi was not clear, since the results of microbiological analysis only provided evidence that their amounts in all investigated soil samples were within normal ranges as well as that their amounts in the corresponding samples of the uprooted trees were much greater than in the case of snapped trees. Therefore, further molecular characterization of microorganisms should be performed to identify if pathogenic species are present and clarify their role. Nevertheless, all used methods, especially IR thermal imaging as a totally non-invasive, fast and very comfortable technique, can be recommended as very useful in preventive screening of the trees’ health status and for early detection of tissue decay that usually hamper trees survival or resistance to extreme weather events.

Determination of boron concentration in uranium fuel samples by ICP-OES following a separation step by cation exchange resin

The boron content of uranium fuel samples with boron concentrations in the range of 0.05–10 µg/g was determined using inductively coupled plasma optical emission spectrometry (ICP-OES) after the uranium was separated by cation exchange. The samples were dissolved in 3 M HNO3 on a hot plate at 150 °C and evaporated to near dryness. The residues were redissolved in 0.2 M HNO3 and passed through a column loaded with Dowex 50WX8-400 resin. Uranium was adsorbed on the resin, while boron was easily eluted with 0.2 M HNO3. The boron content of the effluent was determined using ICP-OES. Several strategies were employed to improve the reliability of the experimentally determined boron content. The addition of mannitol and proper control of the evaporation process were shown to be effective in preventing boron loss during sample dissolution and evaporation. The memory effect was eliminated by flushing the system with 1.5% ammonia for 30 s between successive sample runs, and the matrix match method was used to eliminate the matrix effect arising from mannitol during the ICP-OES analysis. The accuracy of the results of the analysis was determined by addition recovery tests and by comparison with the results of three Chinese certified reference materials (GBW04242, GBW04243, and GBW04232). Using the method we developed, the limit of detection for boron was as low as 0.05 µg/g in uranium fuel samples, and the relative standard deviations for 0.1–0.5 g uranium samples with 0.05–2 µg/g of boron were within 9%.

Valorization of Biomass into Micronutrient Fertilizers

Biological waste constitutes a resource that could be valorised into micronutrient fertilizers. Micronutrient fertilizers (berries seeds residues enriched with micronutrients—blackcurrant Ribes nigrum L., raspberry Rubus idaeus L., strawberry Fragaria × ananasa) produced via biosorption were developed. Micronutrient content was investigated by Scanning Electron Microscope with Energy Dispersive X-ray analysis (SEM-EDX) as an alternative method to Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) which is known as costly, time-consuming and sample-destructive method. X-ray mapping of SEM images and ICP-OES analysis showed the differences in the concentration of micronutrients on the materials surface (natural and enriched biomass—from 3 to 24 times). The highest content of micronutrients (ICP-OES) was achieved for enriched blackcurrant [Cu(II)-12.8 mg g−1, Zn(II)-10.8 mg g−1] and strawberry seeds [Mn(II)-5.13 mg g−1]. The highest atomic concentration of micronutrients was found on the surface (SEM-EDX) of enriched strawberry [24.5% for Cu(II), 8.43% for Mn(II) and 11.1% for Zn(II)]. It was shown that increasing content of micronutrient ions in biological material after biosorption was connected with decreased level of the following cations: Ca(II), Mg(II) and K(I) (ion exchange). The uniform distribution of micronutrient ions was observed on SEM micrographs. The structure of the surface, surface topography (steps, bends and broken edges) were also investigated. The content of micronutrients in biomass determined with ICP-OES and SEM-EDX revealed high correlations between these methods for manganese, zinc and copper ions (0.848, 0.739, 0.735, respectively). Described experiments showed that SEM-EDX was an efficient tool and an alternative for ICP-OES.

Physico-chemical characterization of slag waste from coal gasification syngas plants: Effect of the gasification temperature on slag waste as construction material

Abstract The ash fusion temperature determines the suitability of coal for the entrained flow gasification/combustion process. For this purpose, Indonesian KPU coal samples and their ash and slag contents were comprehensibly characterized via X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), and inductively coupled plasma optical emission spectrometry (ICP-OES) methods. To assess their environmental impacts, leachate solutions were prepared from the discharged slag for ICP-OES analyses. The experimental data were comprehensively explained in terms of ash fusion temperatures and fluidity properties of the coal ashes. More specifically, the coal slagging behavior inside of coal gasifier/combustors necessitated optimization of the operational conditions for subsequent mild slagging. The currently used coal gasification operation temperature ranges favored mild slagging at 1200 to 1300 °C (19.9 to 20.1 bar) and incomplete slagging at 1100...

Corrosion Behavior of Structural Materials for Potential Use in Nitrate Salts Based Solar Thermal Power Plants

Commercial and economic success of concentrated solar power (CSP) plants requires operating at maximum efficiency and capacity which necessitates the use of materials that are reliable at high temperatures. This study investigates the corrosion behavior of structural alloys in molten nitrate salts at three temperatures common to CSP plants. Corrosion behavior was evaluated using gravimetric and inductively-coupled plasma optical emission spectroscopy (ICP-OES) analysis. Surface oxide structure and chemistry was characterized using X-ray diffraction and Raman spectroscopy. Electrochemical behavior of candidate structural alloys Alloy 4130, austenitic stainless steel 316, and super-austenitic Incoloy 800H was evaluated using potentiodynamic polarization characteristics. Gravimetric and ICP-OES analysis indicated that Alloy 4130 exhibited the least corrosion resistance at 500°C compared to SS316 and 800H. However, at 300°C, the three alloys exhibited similar weight gain. Electrochemical evaluation of these candidate materials was observed to correlate well with the corrosion behavior observed from gravimetric and ICP-OES analysis. This study identifies that all three alloys exhibited acceptable corrosion rate in 300°C molten salt, while elevated salt temperatures require the more corrosion resistant alloys, stainless steel 316 and 800H. Characterization of the sample surfaces revealed the presence of spinels at lower temperatures, while Fe2O3 was the dominant iron oxide at higher temperatures for each alloy.