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Graphitic carbon plays a pivotal role in numerous technological applications, including energy storage, energy conversion, and different fields of material science. The transformation of amorphous carbon into graphitic carbon, a process known as graphitization, is important for optimizing the properties of carbon materials. In this study, we explore the catalytic graphitization of polyacrylonitrile (PANs) using various metal salts (LiNO3, Ca(NO3)2·4H2O, and Ni(NO3)2·6H2O). We prepared dimethyl sulfoxide (DMSO) solutions of PAN with different salt concentrations of 5, 10, and 15 wt.%. The different prepared metal salt-mixed PAN/DMSO solutions were dried at 45 °C and this was followed by carbonization processes at 950 °C, with a heating rate of 1 °C min−1 for 1 h under an N2 atmosphere. The resulting graphitic carbon was characterized to determine the influence of salt type and concentration on the degree of graphitization. Our findings provide valuable insights into PAN-derived graphitic carbon's structural and compositional properties. This work underscores the influence of salt concentration in optimizing the graphitization process, offering a pathway to design facile and cost-effective graphitic carbon materials. [ABSTRACT FROM AUTHOR]

Herein we report a general access to silver(i) perfluoroalcoholates, their structure in the solid state and in solution, and their use as transfer reagents. The silver(i) perfluoroalcoholates are prepared by the reaction of AgF with the corresponding perfluorinated carbonyl compounds in acetonitrile and are stable for a prolonged time at −18 °C. X‐ray analysis of single crystals of perfluoroalcoholate species showed that two Ag(i) centers are bridged by the alcoholate ligands. In acetonitrile solution, Ag[OCF3] forms different structures as indicated by IR spectroscopy. Furthermore, the silver(i) perfluoroalcoholates can be used as easy‐to‐handle transfer reagents for the synthesis of Cu[OCF3], Cu[OC2F5], [PPh4][Au(CF3)3(OCF3)], and fluorinated alkyl ethers. [ABSTRACT FROM AUTHOR]

Graphitic carbon plays a pivotal role in numerous technological applications, including energy storage, energy conversion, and different fields of material science. The transformation of amorphous carbon into graphitic carbon, a process known as graphitization, is important for optimizing the properties of carbon materials. In this study, we explore the catalytic graphitization of polyacrylonitrile (PANs) using various metal salts (LiNO3, Ca(NO3)2·4H2O, and Ni(NO3)2·6H2O). We prepared dimethyl sulfoxide (DMSO) solutions of PAN with different salt concentrations of 5, 10, and 15 wt.%. The different prepared metal salt-mixed PAN/DMSO solutions were dried at 45 °C and this was followed by carbonization processes at 950 °C, with a heating rate of 1 °C min−1 for 1 h under an N2 atmosphere. The resulting graphitic carbon was characterized to determine the influence of salt type and concentration on the degree of graphitization. Our findings provide valuable insights into PAN-derived graphitic carbon’s structural and compositional properties. This work underscores the influence of salt concentration in optimizing the graphitization process, offering a pathway to design facile and cost-effective graphitic carbon materials.

Anaerobic digestion is a promising technology for energy recovery from secondary sludge, yet the presence of humic substances in wastewater limits anaerobic digestion. In particular, humic substances make secondary sludge denser and more compact, reducing the availability of organic matter for biodegradation. Here we review the impact of humic substances on the anaerobic process, with emphasis on humic substances properties, effect on sludge structure and composition, effect on hydrolysis, acidolysis and methanogenesis, evolution of humic substrances, and strategies to counteract negative impacts. Strategies include removing humic substances, pretreatment of secondary sludge prior anaerobic digestion, and addition of metal salts, enzymes and organisms. We observed that humic substances with a high E4/E6 ratio, representing the absorbance determined at 465 nm and 665 nm, with a low carbon/nitrogen ratio, and with a low aromaticity are easier to digest anaerobically. The liquid–solid phases distribution of humic substances influences the efficiency of anaerobic digestion, and the repolymerisation of humic substances during anaerobic digestion reduces sludge degradability. [ABSTRACT FROM AUTHOR]

Sauropus androgynus is a precious medicinal herb containing a lot of chlorophyll, used to create a characteristic green color for food products. In this study, chlorophyll was extracted from S. androgynus by stirring fresh grinded leaves at 500 rpm at room temperature for 25 min with a solvent of 40% ethanol and added different salts, such as NaCl, Na2CO3, ZnSO4 to compare stability over time. In parallel with this experiment, S. androgynus blanched with 1% NaCl solvent was added with distinct metal salts to compare the effect of blanching solvent on chlorophyll pigment content and stability. The results showed that under normal extraction conditions at room temperature within 25 min with the addition of 1% of Na2CO3 salt based on the dry matter of materials, the chlorophyll content reached the highest value of 1.351 ± 0.032 mg/g dry matter (d.m.). Samples are sealed, protected from light, and stored at room temperature for 54 days and 124 days at 4 °C, toward the application of food color.

Biomass oxidation in anode electrolyte solution is investigated for energy‐efficient hydrogen production. The redox of polyoxometalate (POM) as both biomass oxidation catalyst in the solution and charge carrier through regeneration at the graphite electrode promotes hydrogenation generation at the cathode, but suffers from a limited rate of biomass degradation due to the complex structure of solid lignocellulosic biomass. Herein, transition metal salts (CuCl2, CrCl3 and FeCl3) are studied as the synergistic catalysts with POM to promote the degradation of raw biomass. Notably, FeCl3 has the most significant effect in promoting the hydrolysis of cellulose by coordinating with the oxygen donor groups of carbohydrates and helps re‐oxidize reduced POM to maintain high oxidation ability of the solution. As a result, the faraday efficiency of hydrogen production at the cathode could reach 90 %. Coupling oxidation of biomass by contiguously recharged metal salts and POM with electrochemical hydrogen evolution, pure hydrogen source with improved economics is obtained at low energy consumption. [ABSTRACT FROM AUTHOR]

This work describes the characterization of pigments and ground layers in two paintings by the renowned Argentinian painter Antonio Berni (1905–1981). The studied paintings are "Toledo" and "Figure" from the collection of the Provincial Museum of Fine Arts in Santa Fe (Argentina). To approach this goal, an integrated investigation comprising in situ X-ray fluorescence measurements by means of a portable system (pXRF), micro-Raman spectroscopy, Attenuated Total Reflection–Fourier transform infrared spectroscopy (ATR-FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS) was carried out. The results revealed a chromatic palette with inorganic pigments, such as ultramarine blue, cobalt blue, lead white, zinc white, yellow cadmium, and hydrated chromium oxide (viridian), together with a preparation layer consisting of a mixture of earth, lead white, and calcite in "Toledo". On the other hand, the preparation layer in "Figure" was characterized as lithopone, a mixture of barium sulfate and zinc sulfide. ATR-FTIR-analysis revealed the formation of metallic soaps in both paintings due to the reaction of fatty acids from a drying oil used as a binder with lead and zinc pigments, as confirmed by comparison with the infrared spectra of synthetic lead and zinc soaps. This study contributes to the understanding of Berni's painting style and the future restoration of both artworks. [ABSTRACT FROM AUTHOR]

Recently, natural dyes are being explored all over the world as safer and highly sustainable bio-based alternatives to synthetic dyes. Agricultural wastes and plant by-products are the most commonly explored alternatives with dual benefits of waste reclamation and sustainable dye production with extra value-adds. Hypercium scabrum plant contains interesting bio-dye molecules with high flavonoids and tannin contents. The present study aims at exploring the potential of H. scabrum plant extract to color wool textiles with a focus on sustainable bio-dye production and fastness properties. The extracted bio-dye was quantitatively (for total phenolic (2.733 mg per CE/g) and total flavonoid (1.140 mg per GAE/g) content using the Folin–Ciocalteu method) and qualitatively (UV–Vis, FT-IR, and EDX) characterized. The effect of dyeing parameters like pH (2–8), temperature (60–90 °C), dry-weight content of plant material as a dye (25–150% o.w.f.), and dyeing time (15–120 min) on color strength (K/S) values were assessed. Color fastness assays showed good resistance to light, washing, and rubbing. The effect of artificial aging (Xenon arc lamp) on the color strength of dyed wool yarns under different exposure times (0–48 h) was explored. The highest color fading occurred in control dyed samples with a first-order rate constant of 131.57 h−1 and a half-life period of 5.26 x 10−3 h. Color difference (ΔE) values suggested that mordanted samples showed less fading compared to control dyed samples at equal times of Xenon exposure. Additionally, the dyed samples were washed in double distilled water, tap water, and 4 g/L NaCl solution to check their effects on the corresponding K/S values while 4 g/L NaCl solution mimics the real conditions of perspiration. Maximum color leaching occurred in 4 g/L NaCl washing with a first-order rate constant of 11.57 min−1. Cost analysis of the dye extraction and dyeing procedure revealed that the process is sustainable and economical. Thus, the use of H. scabrum whole plant can provide a clean, economical, and sustainable source of alternative natural dyes that can be used to substitute synthetic analogs.

The synthesis of MoS2 with chemical vapor deposition (CVD) using sodium molybdate (Na2MoO4) as the Mo precursor produces a big number of large flakes (∼100-300 μm) compared to other CVD methods that use different precursors. In this work, humidity sensors based on MoS2 are developed, whereby MoS2 is grown using this Mo precursor in an aqueous solution form. The final devices exhibit a response-switching during operation under high (>50%) relative humidity conditions, due to the presence of Na2MoO4 residues on their surface. By decreasing the concentration of the aqueous Mo precursor during the CVD process we partially diminish the switching effect, as the Na2MoO4 residue is reduced To completely overcome this issue, we present a post-fabrication surface treatment using hydrochloric acid that removes the Na2MoO4 residue from the devices' surface. Rinsing the devices with an HCl solution results in the elimination of the response-switching effect and the sensors demonstrate a constant positive response from the initial operation steps.

Hole transport material-free carbon-based perovskite solar cells (HTM-free C–PSCs) are recognized as a cost-effective and stable alternative to conventional perovskite solar cells. However, the significant energy level misalignment between the perovskite layer and the carbon counter electrode (CE) results in ineffective hole extraction and unfavorable charge recombination, which decreases the power conversion efficiency (PCE). Here, we report the introduction of metal salts (Al, Ca, and Mg) into graphite/carbon black (Gr/CB) CEs to modify the work function and enhance the hole selectivity of the CE. This modification leads to improved energy level alignment, efficient hole extraction, and reduced charge recombination. The PCE of the HTM-free C-PSC based on Al-modified Gr/CB as the CE material reached 9.91%, which is approximately 12% higher than that of devices employing unmodified Gr/CB CEs. This work demonstrates that by directly incorporating metal salts into the Gr/CB CE, the energy level alignment and hole extraction at the perovskite/carbon interface can be improved. This presents a viable method for enhancing the PCE of HTM-free C–PSCs.

It is interesting and important to develop cost-effective and highly efficient method for the selective reduction of nitroarenes to produce the widely applied anilines. The catalytic reaction directly driven by metal salts during which the real active species would formed is a convenient way, but the detailed mechanism need further investigation. In this work, the performance of different metal salts were studied, and it showed that iron salts were much more promising to serve as catalyst precursor. Moreover, the reaction was remarkably affected by the type of anion. The addition of other salts to the iron salts mediated system had negative effect on the reaction. In-depth study suggested that the in-situ generated hematite (α-Fe2O3) nanoparticles were the real active species. Small and uniform α-Fe2O3 nanoparticles could be formed when the reaction was carried out at relatively low temperature, while the generated nanoparticles were much larger when performed at higher temperature. Under otherwise identical conditions, the in-situ formed α-Fe2O3 also outperformed many other commercial benchmark catalysts. The selective reduction of nitroarenes can be directly driven by iron salts, and the in-situ generated nanoscale hematite was suggested to be the real active species. [ABSTRACT FROM AUTHOR]

The preparation of different carbon-shell morphology microspheres and controllable surface area via using thermoplastic polymers as carbon source was still a challenge. In addition, the unique structure of porous Silica@Carbon (Sil@C) microspheres not only can provide larger surface area and active site, but also have the characteristics of high mechanical strength and easy modification. Herein, we report a simple method to in-situ fixation a series of different morphology graphitized carbon shell (rosa roxburghii, bulk, and carbon sphere shapes) on porous silica microspheres surface. Metal salt assisted polymer carbonization will not only prepare graphitized carbon with different morphology on silica surface, but also facilitate the in-situ carbonization of thermoplastic polymer on the silica microspheres surface instead of internal pores; the more heat of metal salt released during carbonization, the larger the specific surface area of Sil@C. [ABSTRACT FROM AUTHOR]

The pyrolysis of lignocellulosic biomass is a promising technology for obtaining renewable chemicals and fuels to replace fossil-based products. However, due to the complexity of the lignin, cellulose and hemicellulose molecules, a large variety of compounds are often formed, making commercial implementation difficult. The use of a catalyst during reactions has been recognized as one of the major improvements in pyrolysis, allowing the production of selected compounds. Moreover, the large number of available catalysts opens up a wide range of possibilities for controlling the reaction network. Zeolites, hierarchical zeolites, alkali and alkaline earth oxides, transition metals and carbonaceous materials, among others, have been investigated in the pyrolysis of a variety of biomasses. In addition, bifunctional catalysts play a role in pyrolysis, as well as the addition of plastics as hydrogen donors. This review aims to present and discuss in detail state-of-the-art catalytic pyrolysis, focusing on the relationships between the properties of the catalysts and the obtained products. A guideline for selecting catalysts for lignocellulosic biomass is also provided. [ABSTRACT FROM AUTHOR]

Water scarcity is a significant concern, particularly in arid regions, due to the rapid growth in population, industrialization, and climate change. Seawater desalination has emerged as a conventional and reliable solution for obtaining potable water. However, conventional membrane-based seawater desalination has drawbacks, such as high energy consumption resulting from a high-pressure requirement, as well as operational challenges like membrane fouling and high costs. To overcome these limitations, it is crucial to enhance the performance of membranes by increasing their efficiency, selectivity, and reducing energy consumption and footprint. Adsorptive membranes, which integrate adsorption and membrane technologies, offer a promising approach to address the drawbacks of standalone membranes. By incorporating specific materials into the membrane matrix, composite membranes have demonstrated improved permeability, selectivity, and reduced pressure requirements, all while maintaining effective pollutant rejection. Researchers have explored different adsorbents, including emerging materials such as ionic liquids (ILs), deep eutectic solvents (DESs), and graphene oxide (GO), for embedding into membranes and utilizing them in various applications. This paper aims to discuss the existing challenges in the desalination process and focus on how these materials can help overcome these challenges. It will also provide a comprehensive review of studies that have reported the successful incorporation of ILs, DESs, and GO into membranes to fabricate adsorptive membranes for desalination. Additionally, the paper will highlight both the current and anticipated challenges in this field, as well as present prospects, and provide recommendations for further advancements.

In this study, the effects of the catalysis of heavy metals on the pyrolysis of waste polyester textiles (WPTs) and the adsorption behaviors of the pyrolysis products of WPTs for Cr(VI) were explored. TG−DTG analysis indicated that the metal ions catalyzed the pyrolysis process by reducing the temperature of the decomposition of WPTs. The surface morphology and pore structure of the carbons were analyzed using SEM and BET. The results demonstrated that Zn−AC possessed the largest specific surface area of 847.87 m2/g. The abundant acidic functional groups on the surface of the activated carbons were proved to be involved in the Cr(VI) adsorption process via FTIR analysis. Cr(VI) adsorption experiments indicated that the adsorption process was more favorable at low pH conditions, and the maximum adsorption capacities of Zn−AC, Fe−AC, and Cu−AC for Cr(VI) were 199.07, 136.25, and 84.47 mg/g, respectively. The FTIR and XPS analyses of the carbons after Cr(VI) adsorption, combined with the adsorption kinetics and isotherm simulations, demonstrated that the adsorption mechanism includes pore filling, an electrostatic effect, a reduction reaction, and complexation. This study showed that metal salts catalyze the pyrolysis processes of WPTs, and the activated carbons derived from waste polyester textiles are promising adsorbents for Cr(VI) removal. [ABSTRACT FROM AUTHOR]

In this research work, raw poultry manure biochar (RPM-B) was post-modified by two metal salts and then evaluated for P recovery from aqueous solutions in batch mode. The modified biochar characterization showed that RPM-B impregnation with aluminum and manganese salts led to a significant improvement of their surface properties through the pH-zero charge reduction as well as the specific surface areas and the functional group contents increase. Phosphorus recovery tests indicated that the post-treated biochar with AlCl3 (RPM-B-Al) and with KMnO4 (RPM-B-Mn) exhibited relatively high recovery efficiencies with Langmuir's adsorption capacities of 23.5 and 8.4 mg g−1, respectively. Kinetics and isothermal data modeling, as well as the in-depth analytical characterization of the post-modified biochars before and after adsorption, indicates that P recovery occurs homogeneously on monolayer surfaces through mainly anion exchange, precipitation, and electrostatic interactions. On the other hand, P desorption efficiency increases with the desorbing solution pH values. The best P desorption yields were observed for an initial pH of 9.0 to 78% and 80% for RPM-B-Al-P and RPM-B-Mn-P, respectively. All these results suggest that RPM-B-Al and RPM-B-Mn could be considered promising materials for phosphorus recovery from wastewaters with a possible reuse in agriculture as potential soil amendments. [ABSTRACT FROM AUTHOR]

This work describes the characterization of pigments and ground layers in two paintings by the renowned Argentinian painter Antonio Berni (1905–1981). The studied paintings are “Toledo” and “Figure” from the collection of the Provincial Museum of Fine Arts in Santa Fe (Argentina). To approach this goal, an integrated investigation comprising in situ X-ray fluorescence measurements by means of a portable system (pXRF), micro-Raman spectroscopy, Attenuated Total Reflection–Fourier transform infrared spectroscopy (ATR-FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS) was carried out. The results revealed a chromatic palette with inorganic pigments, such as ultramarine blue, cobalt blue, lead white, zinc white, yellow cadmium, and hydrated chromium oxide (viridian), together with a preparation layer consisting of a mixture of earth, lead white, and calcite in “Toledo”. On the other hand, the preparation layer in “Figure” was characterized as lithopone, a mixture of barium sulfate and zinc sulfide. ATR-FTIR-analysis revealed the formation of metallic soaps in both paintings due to the reaction of fatty acids from a drying oil used as a binder with lead and zinc pigments, as confirmed by comparison with the infrared spectra of synthetic lead and zinc soaps. This study contributes to the understanding of Berni’s painting style and the future restoration of both artworks.

Tattooing, the introduction of exogenous pigments into the skin, has a rich history spanning thousands of years, with cultural, cosmetic, and medical significance. With the increasing prevalence of tattoos, understanding their potential complications and contraindications is of growing importance. The most common complications are hypersensitivity reactions, which may vary in morphology and timing. Infectious complications are often due to inadequate aseptic and hygienic practices during the tattooing process or healing period. Tattoo pigment can present diagnostic challenges, affecting cancer diagnosis and imaging. This CME article explores the history, cultural significance, epidemiology, chemistry, technique, contraindications, and complications of tattoos. Appreciating these factors can help individuals considering tattoos understand the safety and potential risks of their body art, and provide physicians with a thorough understanding of tattooing if consulted., Competing Interests: Conflicts of interest Dr Marini reports that in the past, he has received honoraria for speaking engagements from Fotona interest are disclosed in the interest of transparency and full disclosure. All other authors of this work have declared Laser and honoraria for participation in investigational studies with Lumenis. These potential conflicts of that they have no conflicts of interest to disclose., (Copyright © 2024 American Academy of Dermatology, Inc. All rights reserved.)

Taking into account the diversity of fullerene ligands and metal salts, metal–fullerene frameworks (MFFs) present a variety of structures. Currently, the structural control of MFFs mainly relies on the design and synthesis of fullerene ligands, while the influence of metal building units on the structures has been rarely studied. The present work represents a systematical investigation of fullerene-linked supramolecular architectures incorporating different metal salts. Treatment of a bidentate N,N-donors fullerene ligand (L1) with six metal salts ([Zn(NO3)2·6H2O, Cd(NO3)2·4H2O, Cu(NO3)2·3H2O, Cu(OAc)2·H2O, FeCl2·4H2O and FeCl3·6H2O]) produced six one-dimensional MFFs, i.e., ZnL1(NO3)2(H2O)2 (1), CdL1(NO3)2 (2), Cu(L1)(H2O)2(NO3)2 (3), CuL1(OAc)(CH3O) (4), FeL1Cl2 (5) and FeL1Cl2(FeCl4) (6). Compounds 1–3, built with nitrates with different metal centers (M(NO3)2, M = Zn, Cd, Cu), present a 1D stair-like, 1D zigzag, and 1D linear chain structure, respectively. Compound 4, synthesized with another Cu(II) salt, Cu(OAc)2, displays a dinuclear Cu-Cu connected 1D stair-like chain structure, rather than the single Cu linked 1D linear chain obtained from Cu(NO3)2. Compounds 5 and 6, assembled from iron chloride of different oxidation states (Fe(II)Cl2 and Fe(III)Cl3) reveal a 1D zigzag and a 1D stair-like chain structure, respectively. The results demonstrate the significant influences of metal salts on the structures of metal–fullerene frameworks. [ABSTRACT FROM AUTHOR]

[Display omitted] • The co-assembly of SiO 2 and polymethylmethacrylate microspheres was used to fabricate the optimum structure of SiO 2 inverse opal. • By injection of 20 different metal salts in the structure, a blue or red shift of the photonic band gap (PBG) was recorded. • These behaviors were attributed to the unique influence of each salt on the lattice constant of the structures. • The interplay between the hydrophilicity of SiO2 and the hygroscopic nature of the metal salts determined whether the PBG shifted toward blue or red. • The highest redshift in PBG for Hg(NO 3) 2 and blueshift for Zn(NO 3) 2 was 19 nm and 16 nm, respectively. In this paper, SiO 2 inverse opal photonic crystals, made by the co-assembly of SiO 2 and polymethylmethacrylate (PMMA) microspheres, were used to detect 20 different metal salts with a concentration of 0.002 mol/L. Surprisingly, two different behaviors were observed. Some metal salts caused a redshift in photonic bandgap (PBG) while the others led to a PBG's blueshift. The observed different behaviors of salts are due to their distinct influence on the lattice constant of the inverse structures which was precisely investigated by analyzing the field emission scanning electron microscopy (FESEM) images and ultraviolet–visible (UV–Vis) spectroscopy. It has been revealed that the competition between the hydrophilicity of SiO 2 and the hygroscopicity of metal salts led to a shift of PBG toward blue or red. The maximum shift in the PBG range was observed for mercury (II) nitrate salt (19 nm), which indicates a sensitivity of 9.5 nm per concentration unit (mM). Furthermore, the lowest displacement of the PBG was observed for the sodium nitrate salt (5 nm), which represents a sensitivity of 2.5 nm/mM. The lowest and highest values of the detection limit (LOD) for mercury (II) nitrate salt and sodium nitrate salt equal 0.193 mmol/L and 0.887 mmol/L, respectively. In addition, according to the calibration curve, with a regression coefficient of R2 > 0.95, there is a linear relationship between the salt concentration and the displacement of the PBG of the structure. Based on the results illustrating the sensitivity of the synthesized inverse opal to the type and concentration of the salts, inverse opal can be regarded as a promising structure to create a new perspective in the field of chemical sensing. [ABSTRACT FROM AUTHOR]

Treatment of molybdenum-containing wastewater is crucial for mitigating the environmental threat of Mo(VI) ions and recovering valuable metals. Compared to conventional separation methods, adsorbing colloid flotation emerges as a viable way to efficiently remove Mo(VI) ions. However, the current colloidal adsorption reagents have constrained the development of adsorbing colloid flotation due to their poor removal efficiency and narrow solution pH range. To overcome these challenges, Zr(IV) salts and La(III) salts were employed as colloidal adsorption reagents for the first time to remove Mo(VI) ions from wastewater in this work. In particular, the differences in removal efficiency of Mo(VI) ions between Zr(IV) salts, La(III) salts and traditional Fe(III) salts were systematically evaluated over a wide solution pH range. Zr(IV) salts demonstrated robust pH stability, displaying a significant removal efficiency of over 70.00% for Mo(VI) ions during the colloidal adsorption stage across a broad solution pH range from 3 to 11. Even more astonishingly, the removal efficiency of Mo(VI) ions was further enhanced through the synergistic effect of cetyltrimethylammonium bromide (CTAB) during the flotation separation stage. Under the optimal conditions of bubble flotation, the solution turbidity decreased rapidly from 164.50 NTU to 3.33 NTU, and the removal efficiency of Mo(VI) ions reached an impressive 99.10% which was enhanced by 23.73% compared to the colloidal adsorption stage. In conclusion, Zr(IV) salts, serving as colloidal adsorption reagents, have overcome the limitations of traditional colloidal adsorption reagents and exhibit significant potential for the removal of Mo(VI) ions from wastewater. [Display omitted] • Zr(IV) salts and La(III) salts were utilized for the first time to remove Mo(VI) ions. • Zr(IV) salts broke the limitation of solution pH and efficiently removed Mo(VI) ions. • The synergic effect of CTAB significantly enhanced the removal of Mo(VI) ions by Zr(IV) salts. • Adsorbing colloid flotation improved the removal of Mo(VI) ions based on solid-liquid separation. [ABSTRACT FROM AUTHOR]

Solid waste samples consisting of shredded cellulose, coated with either mesoparticles of metallic salts or dried metal nitrate (lutetium, ytterbium, or depleted uranium) solutions, were generated to mimic solid nuclear waste. After burning these samples, the masses of the aerosolized metal cations were quantified by leaching them from air filters and analyzing the leachate with inductively coupled plasma mass spectrometry. The airborne release fractions (ARFs) for Lu and depleted uranium nitrates were 1 × 10-4, and 3 × 10-3 for Lu and depleted uranium mesoparticle salts, respectively. Uncertainties in ARFs were approximately 10% for the metal nitrates and 30% for the metallic mesoparticles. These data are most applicable to waste materials with 1% metal mass loading where the initial respirable fraction of contaminant particles is one. ARFs were consistent across the two metals, but there was an order of magnitude difference with respect to the physical and chemical form (mesoparticle salt versus nitrate). Cellulose combustion literature indicates that combustion pathways were likely affected by off-gassing and endothermic decomposition reactions. In comparison to ARF values from DOE-HDBK-3010-94, "Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear Facilities," this dataset was consistent with previous results but provides a well-characterized and reproducible method for doping cellulosic materials with nuclear waste surrogates to serve as a baseline for future experimental and computational works. [ABSTRACT FROM AUTHOR]

In this paper we presented a study on the color change by retreatment with different agents, of materials dyed with direct dyes.Direct dyes are organic or inorganic substances that contain double-bonded chromophore groups, which have a major role in the affinity of dyes for cellulosic fibers. Direct dye fixation is done by: hydrogen bonds, van der Waals bonds, dipole forces between dye and fiber.The dyeing process is influenced by the following parameters: dye concentration, electrolyte concentration, temperature and bath hydromodule.Most direct dyes do not have adequate color fastness to wet or light treatments. Therefore, these color fastness need to be improved by various retreatment processes.In order to improve the color fastness to wet and light treatments, it is possible to change the structure of the dye by complexing (metal salt treatment), redoing by diazotization and coupling, insolubilization with cationic agents (cationic salts or synthetic resins). The optimal method of treatment is dictated by the structure of the dye and the advantages and disadvantages of each method.In this study, metal salts of CuSO4, K2Cr2O7 and cationic salts (Aniofix D) were used for the retreatment. Following these retreatments, varieties of tint and color variations of the dyeing colors appeared. Tint and color changes must be considered when making dyeing recipes.

In this study, the effects of the catalysis of heavy metals on the pyrolysis of waste polyester textiles (WPTs) and the adsorption behaviors of the pyrolysis products of WPTs for Cr(VI) were explored. TG−DTG analysis indicated that the metal ions catalyzed the pyrolysis process by reducing the temperature of the decomposition of WPTs. The surface morphology and pore structure of the carbons were analyzed using SEM and BET. The results demonstrated that Zn−AC possessed the largest specific surface area of 847.87 m2/g. The abundant acidic functional groups on the surface of the activated carbons were proved to be involved in the Cr(VI) adsorption process via FTIR analysis. Cr(VI) adsorption experiments indicated that the adsorption process was more favorable at low pH conditions, and the maximum adsorption capacities of Zn−AC, Fe−AC, and Cu−AC for Cr(VI) were 199.07, 136.25, and 84.47 mg/g, respectively. The FTIR and XPS analyses of the carbons after Cr(VI) adsorption, combined with the adsorption kinetics and isotherm simulations, demonstrated that the adsorption mechanism includes pore filling, an electrostatic effect, a reduction reaction, and complexation. This study showed that metal salts catalyze the pyrolysis processes of WPTs, and the activated carbons derived from waste polyester textiles are promising adsorbents for Cr(VI) removal.

The emission of volatile organic compounds (VOCs) of polyurethane foam (PUF), mainly the aldehydes and ketones, in an indoor environment is a threat to human beings' health. Considering that salts have the potentials to improve the anti-oxidation ability of PUF to cut down VOCs' emission, therefore, in this article, we aim at, for the first time, investigating VOCs emission of PUF modified with metal salts, such as potassium iodide, potassium thiocyanate, copper chloride and zinc chloride. For that purpose, Fourier infrared spectrometer (FT-IR), VOCs test, thermogravimetric analysis (TGA), scanning electron microscope (SEM) and compression test are applied to analyze the samples aged and not. The results showed the composites had excellent oxidation-resistance capacity and improved mechanical properties while aging. The VOCs test showed the complete elimination of formaldehyde, acetaldehyde and propionaldehyde; the effectively suppressed emission of acetone, methacrolein, butyraldehyde; a slightly suppressed emission of acrolein and butanone, indicating the VOCs emission of PUF can be deducted effectively. This study may provide a new and practical method for reducing the VOCs emission of PUF and other materials. [ABSTRACT FROM AUTHOR]

Different individually applied commercial salts at different concentrations are generally used to precipitate contaminants in wastewater. In this study, we developed a treatment complementary to the lagoon system of a wastewater treatment plant by adding a combination of trivalent metal salts to chemically precipitate phosphate contaminants. Laboratory tests were conducted to determine the most efficient treatment for the removal of phosphate in wastewater by analyzing orthophosphate using the ascorbic acid method. Three trivalent metal salts—iron (III) sulfate, aluminum (III) sulfate, and iron (III) chloride—were combined with each other at three different concentrations, obtaining an experimental design involving 27 treatments replicated three times each. Analysis of variance (ANOVA) with Tukey's test revealed the treatment for which the highest percentage of orthophosphate removal (99.04%) was obtained. Finally, the selected treatment was implemented for field evaluation over three weeks, obtaining an average removal of 93.13%. [ABSTRACT FROM AUTHOR]

Environmental engineering placed green demands on the functional modification of textiles. Here, the combination of bio-based tannic acid, sophora flower extract and metal salts was used to manufacture silk fabrics with flame retardancy and UV resistance via a facile impregnation strategy. With different metal salts treated, the modified silk fabrics named silk/TA/SFE-TE, silk/TA/SFE-Fe and silk/TA/SFE-Cu achieved self-extinguishing in the vertical burning test, with limiting oxygen index values of 31.7 ± 0.4 %, 30.2 ± 0.2 % and 30.9 ± 0.3 %, respectively. In the cone calorimetry test, the peak heat release rate values of the three silk fabrics modified with metal salts were all significantly suppressed, and the total smoke production values of silk/TA/SFE-TE and silk/TA/SFE-Fe were reduced from the original 0.178 m2 to 0.126 m2 and 0.138 m2, respectively. Furthermore, silk/TA/SFE-TE, silk/TA/SFE-Fe and silk/TA/SFE-Cu displayed high ultraviolet protection factor values and thus had good UV resistance, owing to the presence of tannic acid and sophora flower extract. Most importantly, the flame retardancy and UV resistance of the three silk fabrics modified with metal salts were still superior to those of the original silk fabrics after 30 washing cycles. In short, this facile route for the preparation of functionalized silk fabrics provides a novel idea for the development of advanced textiles. [Display omitted] • Combinations of bio-based compounds and metal salts are built on silk fabrics. • Modified silk fabrics achieve self-extinguishing in the vertical burning test. • Modified silk fabrics exhibit high UV protection factors in the UV resistance test. • Modified silk fabrics remain flame retardant and UV resistant after 30 washings. [ABSTRACT FROM AUTHOR]

Coloration of textiles with natural dyes involves huge consumption of chemicals; mainly, metal salt mordants, which pose serious environmental challenges. To mitigate this pollution, more and more environmentally friendly, biodegradable, biocompatible and renewable products should be popularized in dyeing industry. This paper proposes a sustainable and metal salt-free dyeing of wool samples by employing natural mordants extracted from pomegranate peel (Punica granatum L), gallnut (Quercus infectoria L) and catechu (Acacia catechu). The color parameters of dyed wool samples were greatly found to be dependent on the chemical compounds present in respective biomordants and their interaction ability with the functional groups of wool and the dye molecules. The investigated biomordants exhibit different interactions with coloring compounds of Butea monosperma (palas) dye resulting in deep brown, olive green, dark brown, cinnamon, burgundy, and yellowish hues on wool. All the biomordants selected in this study improved dye performance and resulted in a broad beautiful spectrum of colors with acceptable fastness properties. The results encourage the search and exploitation of new plant species as a source of biomordants to replace metallic and toxic mordants currently used in textile industry.

Abstract Background The general approach to the synthesis of metal complexes begins with ligand synthesis, followed by ligand reaction with metal salts to afford organometallic complexes. Our research group first reported a one-pot multicomponent synthesis of chiral oxazolinyl–zinc complexes, in the presence of a large amount of ZnCl2 (0.4–2.6 equiv.), with the yields of some products reaching 90%. Results Our prior strategy was extended to use copper, cobalt, nickel, manganese, palladium or platinum salts as the third component. The one-step method used 1.0 equivalent of a metal salt, such as M(OAc)2·nH2O or MCl2·nH2O (M: Cu, Co, Ni, Pd or Pt, n = 1, 2 or 4), as a reagent to generate chiral salicyloxazoline complexes 1–8 in the reaction of 2-cyanophenol with different d- and l-amino alcohols. Conclusion Complexes 1–8 were obtained using a one-pot method with a sequential strategy. The reaction outcome was demonstrated for three-component reactions between metal salts, amino alcohols and 2-hydroxybenzonitrile to afford organometallic complexes in good yields (65–95%).

Taking into account the diversity of fullerene ligands and metal salts, metal–fullerene frameworks (MFFs) present a variety of structures. Currently, the structural control of MFFs mainly relies on the design and synthesis of fullerene ligands, while the influence of metal building units on the structures has been rarely studied. The present work represents a systematical investigation of fullerene-linked supramolecular architectures incorporating different metal salts. Treatment of a bidentate N,N-donors fullerene ligand (L1) with six metal salts ([Zn(NO3)2·6H2O, Cd(NO3)2·4H2O, Cu(NO3)2·3H2O, Cu(OAc)2·H2O, FeCl2·4H2O and FeCl3·6H2O]) produced six one-dimensional MFFs, i.e., ZnL1(NO3)2(H2O)2 (1), CdL1(NO3)2 (2), Cu(L1)(H2O)2(NO3)2 (3), CuL1(OAc)(CH3O) (4), FeL1Cl2 (5) and FeL1Cl2(FeCl4) (6). Compounds 1–3, built with nitrates with different metal centers (M(NO3)2, M = Zn, Cd, Cu), present a 1D stair-like, 1D zigzag, and 1D linear chain structure, respectively. Compound 4, synthesized with another Cu(II) salt, Cu(OAc)2, displays a dinuclear Cu-Cu connected 1D stair-like chain structure, rather than the single Cu linked 1D linear chain obtained from Cu(NO3)2. Compounds 5 and 6, assembled from iron chloride of different oxidation states (Fe(II)Cl2 and Fe(III)Cl3) reveal a 1D zigzag and a 1D stair-like chain structure, respectively. The results demonstrate the significant influences of metal salts on the structures of metal–fullerene frameworks.

Potentiometric titration, FTIR spectroscopy, 13C solid-state NMR spectroscopy and chemical analysis were used to study the gelation of technical lignins (oxidized hydrolysis, kraft, soda and lignosulfonates) and Pepper lignin in interaction with metal salts (CaCl2, Mg(NO3)2, FeSO4, Co(NO3)2, Pb(NO3)2, Fe(NO3)3, CuSO4, AgNO3). It has been found that compounds that are salts of weak base and strong acid possess an ability to gelation; the metal cation has a standard potential above a certain value, has moderate hydrolysis ability and the cation hydroxide formed in the hydrolysis reaction has a relatively low solubility. At the gel formation, a compounds of the composition R–COO–Mez +–OOC–R, z = 2, 3 were formed. A scheme of intermolecular bonds at the point of lignin hydrogel formation was proposed, according to which, adjacent lignin molecules bound to each other by three types of bonds: ionic between carboxyl groups of lignin and metal cation, coordination between metal cation and water molecules included in the coordination sphere, and hydrogen bonds, binding all components of the system into a single whole. Lignin hydrogels have a high sorption ability with respect to heavy metals such as lead, iron and copper, that, depending on the content of acid groups in lignin and the molar mass of the sorbate, is approximately 25–50% by weight of lignin. This opens up the possibility of using a new type of lignin hydrogels for wastewater treatment of chemical plants. [ABSTRACT FROM AUTHOR]

Polyamide 6 (PA6) and stabilized PA6 with two different thermal stabilizers, (ie, metal salts CuI/KI and hindered amine KYN818 [1,3‐benzendicarboxamide,N,N'‐bis(2,2,6,6‐tetramethyl‐4‐piperidinyl)]) were separately prepared by melt blending and then aged for different time. The effects of aging temperature and aging time on crystallization behaviors of PA6 and stabilized PA6 were systematically investigated by differential scanning calorimetry and X‐ray diffraction. The variations of melting temperature, crystallinity and 2θ values suggest that aging under high temperature will accelerate the formation of crystals initially and then the degradation of molecular chains. The yellowness index and maximum decomposition temperature of stabilized PA6 are higher than that of PA6, which is dominated by different aging mechanisms and properties of stabilizers. In addition, the viscosity of all systems is increased at the preliminary stage, which is caused by the crosslinking network and the post‐polycondensation. The results of dynamic mechanical analysis showed that the glass transition temperature (Tg) decreases because the degradation of molecular chains during the aging process. Moreover, the carbonyl index for stabilized PA6 is lower than PA6, indicating the degradation is hindered by stabilizers. A comparison of the stabilization performance between CuI/KI and KYN818 was investigated to differentiate the long‐term stabilizing efficiency. [ABSTRACT FROM AUTHOR]

Hydrogen generation by the reaction of micrometer-aluminum powder with water at room temperature is hard to proceed due to the inhibition of alumina layer. In this study, a novel strategy of metal salts mediated Al-water reaction was proposed for more efficient and practical hydrogen generation. The effects of metal salt composition and dosage, and water injection rate and volume on hydrogen generation were investigated. The hydrogen yield of 230.0 mL was achieved in the Al/Ni/Cu/H 2 O system within 600 s under the following conditions: 0.24 g aluminum with the molar ratio of Al, Ni and Cu at 10:1:1 and 2 mL water at the injection rate of 2 mL/min, which was equivalent to 70.4% of the theoretical hydrogen yield. Based on the morphology, element composition, crystal structure and electrochemical test results of the obtained composites after reaction, the mechanism of hydrogen production by metal salts mediated Al-water reaction was proposed. Image 1 • The Al/Ni 0·1 /Cu 0·1 /H 2 O system shows the best hydrogen generation performance. • Water injection mode affects hydrogen generation by affecting system temperature. • Micro galvanic cells are formed between Al and metal salts to enhance Al corrosion. • Heat released from chemical replacement reaction accelerate hydrogen generation. [ABSTRACT FROM AUTHOR]

The interaction of phages with abiotic environmental surfaces is usually an understudied field of phage ecology. In this study, we investigated the virucidal potential of different metal salts, metal and ceramic powders doped with Ag and Cu ions, and newly fabricated ceramic and metal surfaces against Phi6 bacteriophage. The new materials were fabricated by spark plasma sintering (SPS) and/or selective laser melting (SLM) techniques and had different surface free energies and infiltration features. We show that inactivation of Phi6 in solutions with Ag and Cu ions can be as effective as inactivation by pH, temperature, or UV. Adding powder to Ag and Cu ion solutions decreased their virucidal effect. The newly fabricated ceramic and metal surfaces showed very good virucidal activity. In particular, 45%TiO2 + 5%Ag + 45%ZrO2 + 5%Cu, in addition to virus adhesion, showed virucidal and infiltration properties. The results indicate that more than 99.99% of viruses deposited on the new ceramic surface were inactivated or irreversibly attached to it.

Purpose: Generally, the interest of studying various factors that affect the level of vitamin C in different types of food has been increased due to its great importance to human health. This study aimed to investigate the effect of different incubation factor variables; pH, temperature and metal salts on the amount of vitamin C of yellow bell pepper extracted in aqueous media. Methods: 200 gm of the grinded yellow bell pepper was added to 500 ml of distilled water for 24 hours with continuous shaking. Then the solution of the preparation was filtered, and the clear filtrate was used to obtain the concentration of vitamin C by redox titration. Equal portions of the filtrate (20ml) were used every time to investigate the effect of the following at different incubation periods on the contents of vitamin C: pH ranges from (3 – 8), temperature (-18, 4, 37, 40, 60, 90 Cᵒ) and metal salts (ZnCl2, MgCl2, FeCl2) of the same concentration (0.1M). The amount of vitamin C in the treated filtrate was estimated after the end of each incubation time. Results: There was a significant loss in the amount of vitami [ABSTRACT FROM AUTHOR]

In this paper we presented a study on the color change by retreatment with different agents, of materials dyed with direct dyes. Direct dyes are organic or inorganic substances that contain double-bonded chromophore groups, which have a major role in the affinity of dyes for cellulosic fibers. Direct dye fixation is done by: hydrogen bonds, van der Waals bonds, dipole forces between dye and fiber. The dyeing process is influenced by the following parameters: dye concentration, electrolyte concentration, temperature and bath hydromodule. Most direct dyes do not have adequate color fastness to wet or light treatments. Therefore, these color fastness need to be improved by various retreatment processes. In order to improve the color fastness to wet and light treatments, it is possible to change the structure of the dye by complexing (metal salt treatment), redoing by diazotization and coupling, insolubilization with cationic agents (cationic salts or synthetic resins). The optimal method of treatment is dictated by the structure of the dye and the advantages and disadvantages of each method. In this study, metal salts of CuSO4, K2Cr2O7 and cationic salts (Aniofix D) were used for the retreatment. Following these retreatments, varieties of tint and color variations of the dyeing colors appeared. Tint and color changes must be considered when making dyeing recipes. [ABSTRACT FROM AUTHOR]

An environmentally friendly solvent, namely, polypropylene glycol 425, has been proposed for the extraction of metal ions from chloride solutions using trioctylmethylammonium thiocyanate. The quantitative characteristics of the extraction of Fe(III), Zn(II), and Mn(II) using trioctylmethylammonium thiocyanate in the polypropylene glycol 425–NaCl–H2O system have been found. For extracting Fe(III), Zn(II), and Mn(II), it has been shown that the patterns of the extraction of metal ions remain unchanged and the replacement of the solvent does not lead to the loss of extraction capacity for trioctylmethylammonium thiocyanate. The mechanism of the extraction of the metal ions under study has been determined. The proposed extraction system can be used to purify Mn(II) from Fe(III) and Zn(II). [ABSTRACT FROM AUTHOR]

In this study, the apparent activation energy of coal samples during pyrolysis with NiCl2, FeCl3, Ni(NO3)2 and Fe(NO3)3 in-situ loaded on was calculated. The results show that metal salts promote the devolatilization process with the activation energy decreased by 24.28%, 13.27%, 38.61%, and 41.53%, corresponding to NiCl2, FeCl3, Ni(NO3)2 and Fe(NO3)3 respectively. And the catalytic effect on the evolution of H2 and CH4 was also studied via TG-MS test. Except Fe(NO3)3, the adding of other metal salts made activation energy of CH4 and H2 descend. NiCl2-coal sample has the least activation energy of CH4, which indicates a closer interaction with coal matrix compared with Ni(NO3)2. However, the activation energy of H2 for NiCl2-coal sample and Ni(NO3)2-coal sample varies little. To further investigate the catalytic effect during pyrolysis, hydrogen distribution in solid residues was analyzed according to the FTIR spectrums. The relatively abundant hydrogen content in aromatic structure when ferric salts were added indicates the hydrogen transfer to aromatic rings under the effect of Fe element. And FeCl3 has a superior effect compared with Fe(NO3)3. The difference in the catalytic effect between metal nitrates and metal chlorides could be ascribed to the different behaviors during the decomposition process. [ABSTRACT FROM AUTHOR]

Purpose. Development of ecologically safe technology of finishing the textile materials using strawberry sepals extract and determination of influence for a mordant with salts from various metals on coloring quality. Methodology. The technological parameters of the dyeing process by strawberry sepals extract were determined for linen, cotton, viscose and wool textile materials using pre-treatment with or without metal salts of Cu2+, Zn2+, Ni2+, Fe3+, Al3+. The color characteristics of the samples were determined using Adobe Photoshop CS6 software to evaluate the color quality. The resistance of the dyeing the textile materials to physical and chemical influences were determined by standard methods for textile materials. Findings. Ecologically safe technology of finishing the cellulosic and wool textile materials using strawberry sepals extract has been developed. The dyeing of textile materials made from cellulose fibers made it possible to obtain coloration from light to dark brown. After dyeing, the brightest samples were found based on wool fibers. Depending on the type of mordant, the following colors were obtained: Cu2+ cation made it possible to obtain green-brown shades, Al3+, Zn2+, Ni2+ cations gave colors in the yellowbrown shades; Fe3+ cation gave colors in black and brown shades. In general, the color fastness to wet and dry crocking for textile materials after dyeing with strawberry sepals extract are maximum for all specimens pre-treated with ferric cations except cotton and linen materials. The stability of color to perspiration in cotton, linen, viscose and wool samples ranges from 4 to 5 points. Color fastness to washing for samples from cellulose fibers are preferably 4-5 points, and for woolen is 4 points. Originality. The scientific novelty of the work is to determine the basic regularities of the dyeing process after pre-treatment with salts of metals Cu2+, Zn2+, Ni2+, Fe3+, Al3+ using as a dye of the strawberries sepals extract, which is a waste of the food industry. Practical value. The technological parameters of the dyeing process by strawberry sepals extract, for cotton, viscose and woolen textile materials using pretreatment with metal salts of Cu2+, Zn2+, Ni2+, Fe3+, Al3+ were developed. [ABSTRACT FROM AUTHOR]

Purpose: Metal salts are used in formulation of dry powder inhalers (DPIs) for different purposes. Recently the role of these salts in production of small, dense but highly dispersible particles has emerged. In this study the effect of some such salts on dispersibility and respirability of spray dried levofloxacin formulations was evaluated in normal and reduced inhalation air flow or by increasing powder filling in capsules. Methods: levofloxacin was co-spray dried with different concentrations of common metal chlorides (NaCl, KCl, CaCl2 and MgCl2) either with or without leucine as dispersibility enhancer. Particle size, moisture, morphology, triboelectrification tendency and fine particle fraction (FPF) of resulting powders were evaluated. In addition, the effect of these salts and leucine on dispersibility of resulting powders in reduced air flow rate and increased capsule filling mass were evaluated. Results: Presence of higher tested concentrations of divalent cations increased water content, and reduced FPF significantly. Addition of leucine reduced water content and electrostatic charge, increased particle size and FPF and improved spray drying yield significantly. Lower concentrations of salts did not affect FPF of leucine containing powders significantly, but presence of 2.5% NaCl or MgCl2 preserved the dispersibility in higher capsule fillings. A 2.5% concentration of NaCl in such formulations preserved dispersibility in lower air flows. Conclusion: Higher amounts of divalent salts increases triboelectrification and moisture absorption, and reduces FPF. Lower concentrations of NaCl could not improve FPF of leucine containing formulations significantly, but preserves dispersibility in low air flows and high capsule fillings. [ABSTRACT FROM AUTHOR]

Metals are present as mixtures in the environment, yet testing such complex mixture poses design and technical challenges. One possible solution is the use of fixed ratios, i.e. rays of increasing metal concentrations. But fixed ratios rays are compromised when soils dosed with metal salts are leached due to metal-soil selectivity rules. Two alternative metal forms, metal oxides and spinel minerals of quinary metal mixtures (Pb, Cu, Co, Ni, Zn), were evaluated for their toxicity to soil microorganisms measured by the activity of ammonia monooxygenases and acid-phosphatases in three soils. Leaching, a required step for salts, had a larger effect on ammonia monooxygenases than metals. Generally, metal salts were the most toxic form, while the spinel minerals were the least toxic form. Two extractants, CaCl2 and DTPA, were evaluated for their ability to link toxicity to metals across all three metal forms. Salt toxicity was closely linked to CaCl2 extractable concentrations but DTPA was the most appropriate for oxides. We strongly recommend combining fixed ratio rays with metal oxides for metal mixture studies, since soil ratios created using oxides were more precise and required less experimental effort compared to salts and spinel minerals. Furthermore, because DTPA and CaCl2 closely tracked the toxicity of more realistic metal forms (i.e. oxides), we recommend that field studies investigating metal mixtures use both DTPA and CaCl2. • Metal oxides are recommended for conducting metal mixture studies with a fixed ratio ray design. • Leaching soils with artificial rainwater affects soil enzyme activity. • Metal salts are more bioaccessible and toxic than spinel and metal oxides. [ABSTRACT FROM AUTHOR]

This study was undertaken to propose alternative use for teak leaves, a timber industry byproduct, as potential dyeing source for wool fibers. The coloring potential of anthraquinone colorants from teak leaves were studied on wool with pre-mordanting method using double and triple mix metal salt combinations (ferrous sulphate, stannous chloride and potassium aluminum sulphate) as mordants. Thirty-six sober and elegant shades were developed on wool by varying the type of metal involved in combination as well as concentration of the dye. The hue of color developed ranged from light orange—brown to dark brown. The color strength (K/S) has been found to be very good in dyed woolen yarn samples and particularly was highest for iron + alum combination. Color fastness with respect to light exposure washing, rubbing for the developed shades ranged between good to very good, which confirmed the possibility of using waste leaves of Tectona grandis as a source of effective brown natural dye.