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Abstract Soot stain from diverse sources is the most common stain that stains historical paper documents found in libraries, museums, and storage facilities. It is believed to be one of the types of deterioration that arises from the contact between stains and paper sheets. Therefore, in the present work, the effectiveness of the synthesized hybrid nanogel consisting of carbopol and nanoparticles (NPs) of ZnO, TiO2, or Fe3O4, in low and high-viscosity forms, for eliminating soot stains from historical paper manuscripts was conducted. The prepared hybrid nanogels were characterized utilizing the TEM, AFM, XRD, DLS, and Zeta Potential techniques. Following preparation, the soot-stained paper samples were heated to 105 °C for 6 days, a process known as accelerated thermal aging. Surface morphology, mechanical properties and the color change of the paper samples were investigated. The prepared hybrid nanogel had a spherical shape with well-defined edges and uniform size, with an average particle diameter ranging from 30 to 35 nm. There was no significant NPs agglomeration seen, suggesting uniform dispersion in the carbopol matrix. Additionally, the prepared gels' crystal structure and phase purity were revealed by the XRD analysis results. Paper fibers were visible in some parts of the treated sample with TiO2/carbopol hybrid nanogel at high-viscosity before aging. Cleaning soot-stained paper samples using high-viscosity Fe3O4/carbopol hybrid nanogel is more successful than using low-viscosity nanogel. the sample treated with high-viscosity ZnONPs/carbopol hybrid nanogel produced the highest total color differences (ΔE) (26.17). The paper sample treated with high-viscosity ZnO/carbopol hybrid nanogel exhibited the maximum tensile strength (61.8 N/mm2) and elongation at break (1.174%). The evaluation of the paper samples both before and after the cleaning process revealed that, the treatment with high-viscosity ZnO/carbopol hybrid nanogel gave the best results in removing soot stains from stained paper samples.

Abstract There are many paper manuscripts at museums, stores, and libraries that have different stains. The dust stains and soil remains played an important role in the degradation of these manuscripts. Therefore, the cleaning process for these stains is important to process. Unfortunately, the removal of stains by some traditional techniques can be hazardous to the paper's fibers. Therefore, this study aims to evaluate innovative nanoparticle gels in the cleaning process of dust stains from paper manuscripts. The synthesized nanomaterials [Fe3O4, TiO2, and ZnO]/Carbopol hybrid nanogel were examined in order to investigate the surface morphology, determine the physio-chemical properties, for phase structure, using scanning electron microscope (SEM), transmission electron microscope (TEM), AFM, DLS, XRD, and Zeta potential. Some stained paper samples were prepared and exposed to accelerated thermal aging at 100 °C for 72 h. The evaluation of the cleaning by nanogel was performed by different analytical procedures containing investigation with a USB digital microscope, SEM, color change, mechanical properties, and ATR-FTIR analysis. The results of this study showed that ZnO/Carbopol hybrid nanogel at high viscosity gave the best results in the cleaning process of mud stains through the ability to dismantle mud particles and increase surface contact with the solvent. The aged treated sample with high viscosity form of ZnO NPs/carbopol hybrid nanogel gave the highest tensile strength value of (56.0 N). The treated samples with the high viscosity form of ZnO NPs/carbopol hybrid nanogel gave the highest value of elongation (1.398%) before aging. It also does not affect the chemical composition of the paper after cleaning it, but rather on the whole, it bites the hydration of the paper, which positively affects the properties of the treated paper.

There are many paper manuscripts at museums, stores, and libraries that have different stains. The dust stains and soil remains played an important role in the degradation of these manuscripts. Therefore, the cleaning process for these stains is important to process. Unfortunately, the removal of stains by some traditional techniques can be hazardous to the paper's fibers. Therefore, this study aims to evaluate innovative nanoparticle gels in the cleaning process of dust stains from paper manuscripts. The synthesized nanomaterials [Fe3O4, TiO2, and ZnO]/Carbopol hybrid nanogel were examined in order to investigate the surface morphology, determine the physio-chemical properties, for phase structure, using scanning electron microscope (SEM), transmission electron microscope (TEM), AFM, DLS, XRD, and Zeta potential. Some stained paper samples were prepared and exposed to accelerated thermal aging at 100 °C for 72 h. The evaluation of the cleaning by nanogel was performed by different analytical procedures containing investigation with a USB digital microscope, SEM, color change, mechanical properties, and ATR-FTIR analysis. The results of this study showed that ZnO/Carbopol hybrid nanogel at high viscosity gave the best results in the cleaning process of mud stains through the ability to dismantle mud particles and increase surface contact with the solvent. The aged treated sample with high viscosity form of ZnO NPs/carbopol hybrid nanogel gave the highest tensile strength value of (56.0 N). The treated samples with the high viscosity form of ZnO NPs/carbopol hybrid nanogel gave the highest value of elongation (1.398%) before aging. It also does not affect the chemical composition of the paper after cleaning it, but rather on the whole, it bites the hydration of the paper, which positively affects the properties of the treated paper. [ABSTRACT FROM AUTHOR]

Results of a comprehensive study of the material microstructure of refractory samples after service in a blast furnace with a useful volume of 2200 m3 for 14 years are presented. Structural and genetic analysis establishes a typical sequence of degeneration and wear processes of the ceramic furnace skull, including six stages: formation of micro-and macro-cracks; condensation of zinc vapor; zinc oxidation with formation of fire-resistant ZnO zincite and deposition of carbon black; chemical interaction of zincite with mullite and corundum to form ganite ZnAl2O4 and willemite 2ZnO·SiO2; partial oxidation of silicon carbide with the release of silica glass SiO2, eutectic melt of complex composition, and willemite. Due to intense accumulation of capillary pores, infiltration of molten slag into the volume of refractories does not occur. Wear of refractories within the furnace is a complex, mainly thermochemical mechanism, and a slow rate due to formation of a garnish containing refractory compounds. [ABSTRACT FROM AUTHOR]

A biphasic [Mn(dipya)(H2O)4](tpht)/{[Zn(dipya)(tpht)]·H2O}n complex material, I (dipya = 2,2'-dipyridylamine, tpht2- = dianion of terephthalatic acid) was synthesized by ligand exchange reaction and characterized by XRPD and FTIR spectroscopy. A ZnO/ZnMn2O4 composite, II, has been prepared via thermal decomposition of I in an air atmosphere at 450 °C. XRPD, FTIR and FESEM analyses of II revealed the simultaneous presence of spherical nanoparticles of wurtzite ZnO and elongated nanoparticles of spinel ZnMn2O4. The specific surface area of II was determined by the BET method, whereas the volume and average size of the mesopores were calculated in accordance with the BJH method. The measurements of the mean size, polydispersity index and zeta potential showed colloidal instability of II. Two band gap values of 2.4 and 3.3 eV were determined using UV-Vis diffuse reflectance spectroscopy, while the measurements of photoluminescence revealed that II is active in the blue region of the visible spectrum. Testing of composite II as a pigmentary material showed that it can be used for the colouring of a ceramic glaze. [ABSTRACT FROM AUTHOR]

This paper presents a hydrometallurgical treatment of electric arc furnace (EAF) dust taken from a Vietnamese steelmaking plant to obtain zinc oxide (ZnO) nanoparticles by using aqueous ammonium carbonate solution as a leaching agent. Characterization of the EAF dust was conducted by XRD technique, SEM observation, and manual wet chemical analysis. The results showed that total zinc (Zn) of the dust was 42.69 wt.% and existed mainly in the forms of zincite - ZnO, simonkolleite - Zn5(OH)8Cl2H2O, and franklinite - ZnFe2O4. The leached condition, in which the ammoniac carbonate concentration was 300 g/l and the time was 90 minutes, was found to provide the highest leaching efficiency of 85.29 % when the temperature was fixed at 60 oC and the ratio of solid/liquid was 1/6. After some steps of the subsequent treatment, the ZnO nanoparticles with the purity of 99.5 % and the size of 100 nm were obtained from thermal decomposition of zinc carbonate hydroxide - Zn5(CO3)2(OH)6.

Results are presented for a comprehensive study of the chemical and material composition, as well as the macrostructure, of refractory samples after over 14 years service in a blast furnace hearth with a useful volume of 2200 m3. Sample carbon content is determined using a comprehensive method. Zinc-containing phase formation is established in both the ceramic nozzle area oxide refractories and within the carbon lining of the furnace tuyere zone and hearth. Furnace refractory wear is complex, predominantly by a thermochemical mechanism, and a slow rate due to garnish formation containing refractory compounds. [ABSTRACT FROM AUTHOR]

Biogenic metal oxide nanoparticles (NPs) have emerged as a useful tool in biology due to their biocompatibility properties with most biological systems. In this study, we report the synthesis of copper oxide (CuO), zinc oxide (ZnO) nanoparticles (NPs), and their nanocomposite (CuO–ZnO) prepared using the phytochemical extracts from the leaves of Dovyalis caffra (kei apple). The physicochemical properties of these nanomaterials were established using some characterization techniques including X-ray diffraction analysis (XRD), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The XRD result confirmed the presence of a monoclinic CuO (Tenorite), and a hexagonal ZnO (Zincite) nanoparticles phase, which were both confirmed in the CuO–ZnO composite. The electron microscopy of the CuO–ZnO, CuO, and ZnO NPs showed a mixture of nano-scale sizes and spherical/short-rod morphologies, with some agglomeration. In the constituent's analysis (EDX), no unwanted peak was found, which showed the absence of impurities. Antioxidant properties of the nanoparticles was studied, which confirmed that CuO–ZnO nanocomposite exhibited better scavenging potential than the individual metal oxide nanoparticles (CuO, and ZnO), and ascorbic acid with respect to their minimum inhibitory concentration (IC50) values. Similarly, the in vitro anticancer studies using MCF7 breast cancer cell lines indicated a concentration-dependent profile with the CuO–ZnO nanocomposite having the best activity over the respective metal oxides, but slightly lower than the standard 5-Fluorouracil drug. [ABSTRACT FROM AUTHOR]

Zincite (ZnO) nanoparticles are prepared by adopting reflux assisted co-precipitation method. Prepared product is subjected to different instrumental techniques to investigate its morphology and lattice structure. Rietveld refinements are performed on XRD results and values of various lattice parameters are calculated and structural model of ZnO is predicted. The morphology of the product is analyzed with the help of scanning and transmission electron microscopies (SEM and TEM). The size of prepared nanoparticles is in the range of 80–100 nm where as some larger particles having irregular morphology with size up to 1 μm are also observed in the product. Prepared product is also used as fuel additive and its effect on different fuel parameters is studied. The combustion characteristics (flash and fire point) and physical characteristics (cloud and pour point, kinematic viscosity and specific gravity) of fuel are studied in the presence of 10, 15 and 20 ppm dosage of additive. ZnO is used as nanoadditive for enhancing concrete durability. Concrete pellets are formed with different dosage (0, 0.1, 0.5, 1.5 w/w%) of nanoadditive. Ratio of cement, sand and nanoadditive is kept as 33:66:1 respectively in all concrete samples with constant amount of water. Effect of nanoadditve is studied on different properties of cement such as aging, porosity, compressive strength, specific heat, thermal conductivity and thermal diffusivity. ZnO nanoadditive is found to be effective in modulating both mechanical and thermal properties of concrete samples. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) is one of the most studied biomaterials for orthopaedic applications, yet its commercialization holds in a few of the lags, such as non-antibacterial activity and target deficiency. In this context, we aimed to design a biphasic nanoassembly of Ferric-HAp-Zincite (ZFHAp) via a one-step co-precipitation method. Ferric-HAp obtained Ca 9·333 Fe 1·167 (PO 4) 7 phase in all the samples, and the secondary phases such as Ca 9 Fe(PO 4) 7 and Ca 28·8 Fe 3·2 (PO 4) 21 O 0.5 were governed by the Fe dopant concentration. Along with ferric-HAp, zincite phases were present in all the samples depending on the concentration of Zn precursor. The synthesized ZFHAp samples were hexagonal in structure with size <100 nm, and a dual morphology, i.e., rod-shaped (77.8 ± 10 nm; major corresponding to HAp) and particulate shaped (30.9 ± 5 nm; minor due to Zincite). Doping of iron imparted paramagnetism resulting in the magnetic target efficiency. ZFHAp samples showed excellent self-antibacterial activity against clinically significant two Gram-positive (E. hirae, S. aureus) and two Gram-negative (E. coli, S. paratyphi) bacteria with lower MIC values (60–80 μg/ml). The antibacterial mechanism was found to be ROS independent and due to the linear release of Zn2+ and Fe3+ ions. The designed ZFHAp samples showed no cytotoxicity up to 5 mg/mL and exhibited 3 times higher bone cell proliferation along with the significant Alkaline Phosphatase (ALP) activity. The prepared nanomaterials also did not show any inflammatory response to bone cells. These findings entitle ZFHAp as a potential candidate for orthopaedic as well as other biomedical applications subject to further clinical trials. [ABSTRACT FROM AUTHOR]

Phase equilibria of the ZnO–SiO 2 , Al 2 O 3 –SiO 2 and ZnO–Al 2 O 3 –SiO 2 systems at liquidus were characterized at 1340–1740 °C in air. The ZnO–Al 2 O 3 subsolidus phase equilibria were derived from the experiments with the SiO 2 - and CaO + SiO 2 -containing slags. High-temperature equilibration on silica or platinum substrates, followed by quenching and direct measurement of Zn, Al, Si and Ca concentrations in the phases with the electron probe X-ray microanalysis (EPMA) was used to accurately characterize the system. Special attention was given to zincite phase that was shown to consist of two separate ranges of compositions: round-shaped low-Al zincite (<2 mol.% AlO 1.5) and platy high-Al zincite (4–11 mol.% AlO 1.5). A technique was developed for more accurate measurement of the ZnO solubility in the low-ZnO phases (corundum, mullite, tridymite and cristobalite) surrounded by the ZnO-containing slag, using l -line for Zn instead of K-line, avoiding the interference of secondary X-ray fluorescence. Solubility of ZnO was found to be below 0.03 mol.% in corundum and cristobalite, and below 0.3 mol.% in mullite. Present experimental data were used to obtain a self-consistent set of parameters of the thermodynamic models for all phases in this system using FactSage computer package. The modified quasichemical model with two sublattices (Zn2+, Al3+, Si4+) (O2−) was used for the liquid slag phase; the compound energy formalism was used for the spinel (Zn2+,Al3+)[Zn2+,Al3+,Va] 2 O2- 4 and mullite Al3+ 2 (Al3+,Si4+) (O2−,Va) 5 phases; the Bragg-Williams formalism was used for the zincite (ZnO, Al 2 O 3); other solid phases (tridymite and cristobalite SiO 2 , corundum Al 2 O 3 , and willemite Zn 2 SiO 4) were described as stoichiometric. Present study is a part of the research program on the characterization of the multicomponent Pb–Zn–Cu–Fe–Ca–Si–O–S–Al–Mg–Cr–As–Sn–Sb–Bi–Ag–Au–Ni system. [ABSTRACT FROM AUTHOR]

• Zinc oxide nanoparticles (ZnONPs) were synthesized using solution combustion method. • They were characterized using UV–vis spectroscopy, FTIR, XRD, SEM, and EDX. • They showed non- intercalation mode of binding with a binding efficiency of 3.563 × 105 M−1. • They exhibited cytotoxicity against LN-18, MCF-7, A-549, and SH-SY5Y cells. • The descending order of susceptibility to ZnONPs is LN-18

Biogenic metal oxide nanoparticles (NPs) have emerged as a useful tool in biology due to their biocompatibility properties with most biological systems. In this study, we report the synthesis of copper oxide (CuO), zinc oxide (ZnO) nanoparticles (NPs), and their nanocomposite (CuO–ZnO) prepared using the phytochemical extracts from the leaves of Dovyalis caffra (kei apple). The physicochemical properties of these nanomaterials were established using some characterization techniques including X-ray diffraction analysis (XRD), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The XRD result confirmed the presence of a monoclinic CuO (Tenorite), and a hexagonal ZnO (Zincite) nanoparticles phase, which were both confirmed in the CuO–ZnO composite. The electron microscopy of the CuO–ZnO, CuO, and ZnO NPs showed a mixture of nano-scale sizes and spherical/short-rod morphologies, with some agglomeration. In the constituent’s analysis (EDX), no unwanted peak was found, which showed the absence of impurities. Antioxidant properties of the nanoparticles was studied, which confirmed that CuO–ZnO nanocomposite exhibited better scavenging potential than the individual metal oxide nanoparticles (CuO, and ZnO), and ascorbic acid with respect to their minimum inhibitory concentration (IC50) values. Similarly, the in vitro anticancer studies using MCF7 breast cancer cell lines indicated a concentration-dependent profile with the CuO–ZnO nanocomposite having the best activity over the respective metal oxides, but slightly lower than the standard 5-Fluorouracil drug.

Results of a comprehensive study of the material composition and microstructure of 20 skull samples taken after blowing out AO EVRAZ NTMK blast furnace No. 6 are provided. More than 30 mineral and metal phases of different chemical classes are diagnosed in skull samples. Unlike the skull of blast furnaces of other metallurgical plants (NLMK, ZSMK), NTMK blast furnace skull has an abnormally high content of titanium, zinc, and vanadium compounds, as well as heavy non-ferrous metals and sulfur. On the basis of detailed petrographic analysis, five structural and genetic types (versions of composition and origin) of the skull are identified. Skull versions contain a large amount of grenal, which is dominated by refractory compounds of titanium and vanadium carbonitrides of the general formula (Ti, V)(C, N). [ABSTRACT FROM AUTHOR]

Pure zinc oxide NPs (ZnO NPs) have been synthesized using a simple eco-friendly approach using fruit extracts of Hyphaene thebaica. XRD pattern indicated zincite and highly crystalline phase of ZnO NPs. UV–Vis spectrum revealed surface plasmon resonance at 372 nm and bandgap of 3.36 eV. FTIR spectrum indicated characteristic Zn–O vibration at 450 cm−1. HRTEM images indicated particle size in the range of 8–23 nm having a quasi spherical morphology. Raman shift was observed at 297 cm−1, 405 cm−1 and 548 cm−1. Excellent protein kinase (PK) inhibition and varying antimicrobial potential against different bacterial and fungal strains is reported. E. coli and A. flavus were found as the most susceptible microbial strains. Hemocompatability of the ZnO NPs was revealed. ZnO NPs indicated a dose dependant cytotoxicity. MTT assay revealed a median lethal concentration (IC50) of 106 µg/mL against Leishmania tropica. Different antioxidant assays indicated the antioxidant potential of ZnO NPs. Hyphaene thebaica mediated ZnO NPs revealed excellent therapeutic performance and can used as a potential candidate for diverse biomedical applications. [ABSTRACT FROM AUTHOR]

Structural and color variations of Phthalein dyes immobilized zinc oxide supported Silica-titania nanocomposite in different pHs 1–12. [Display omitted] • Owed to rapid responsive pH sensing attributes, the zinc-supported silica-titania (Z/ST) is synthesized by sol-gel method. • The influence of dyes is examined on the structural and optical properties of Z/ST nanocomposite. • Microscopic analyses possessed that Z/ST and dyes immobilized Z/ST have crack-free porous morphology. • The P-Z/ST possessed 0.3s against pH 12 and pka 10 and Hph-Z/ST revealed time response 0.68 s and high pka around 11. • All three nanocomposites attributed stable and fast responses in basic media. Owed to rapid responsive pH sensing attributes, the zinc-supported Silica-titania (Z/ST) nanocomposite is synthesized by the sol-gel method. Three distinct pH dyes such as phenolphthalein, creosol red, and phenol red are immobilized in Z/ST to examine their influence on the structural and optical properties of Z/ST nanocomposite. Microscopic analyses possessed that Z/ST and dyes immobilized Z/ST have crack-free porous morphology. The phenol red immobilized Z/ST (P-Z/ST) has a low surface roughness ∼0.5 nm, ultra-thin coating ∼2.1 nm, and more hydrophilic features than C-Z/ST (creosol red immobilized Z/ST), and HPh-Z/ST (phenolphthalein immobilized Z/ST). The P-Z/ST possessed 0.3 s against pH 12 and pka 10, C-Z/ST shows a time response 0.5 s and pka (negative log of the acid dissociation constant) value around 8, while Hph-Z/ST revealed a time response 0.68 s and high pka around 11. All three nanocomposites attributed stable and fast responses in basic media. [ABSTRACT FROM AUTHOR]

Terbium doped ZnO nanoparticles were synthesized via co-precipitation method using sodium citrate as a capping agent to study optical and electrical properties. The crystalline structure and the unit cell parameters were refined by the Reitveld analysis, infers that the nanomaterials crystallized in hexagonal zincite structure. The calculated grain size using Scherrer's equation and the Williamson hall plot is found to be similar in values. Ensuing particle gives green emission due to the transitions from the excited 5D4 to the lower 4f energy levels. From the dielectric study, it is confirmed that the synthesized nanocrystal is useful for higher frequency applications. [ABSTRACT FROM AUTHOR]

Abstract Phase equilibria of the binary PbO-ZnO and ternary PbO-ZnO-SiO 2 systems have been experimentally investigated at 1033–1898 K (760–1625 °C) for oxide liquid in equilibrium with air and solid oxide phases: tridymite or cristobalite (SiO 2), willemite (Zn 2 SiO 4), zincite (ZnO), larsenite (PbZnSiO 4) and lead-zinc melilite (Pb 2 ZnSi 2 O 7) covering the ranges of concentrations not studied before. High-temperature equilibration on primary phase or inert metal (platinum) substrates, followed by quenching and direct measurement of the Pb, Zn and Si concentrations in the phases with the electron probe X-ray microanalysis (EPMA) has been used. Liquidus phase equilibrium data is essential for the development of the thermodynamic model. [ABSTRACT FROM AUTHOR]

Zinc is present in electric arc furnace dust (EAFD) mainly in two basic minerals, namely as franklinite ZnFe2O4 and/or zincite ZnO. While zincite is relatively reactive and easily treatable, franklinite is considerably refractory, which causes problems during EAFD processing. In this work EAFD containing 18.53% Zn was leached in water solution of ammonium carbonate. This leaching solution selectively leaches zincite, while franklinite is refractory and stable against leaching in this case. The temperature dependence of zinc leaching from EAFD was studied and the activation energy EA was determined by two methods: 1.) classically based on zinc chemical analyses from the leaching solution and 2.) by using of X-Ray diffraction qualitative phase analyses of leaching residues. The determined values of activation energies 37.41 and 38.55 kJmol–1 match perfectly, which show the excellent possibility of using X-Ray diffraction toward the study of leaching kinetics at properly chosen experimental conditions. The important result is the determination of the amount zincite and franklinite in EAFD, which is not possible by using of classical chemical methods.

The primary goal of the study was to establish corrosivity category in accordance with ISO 9223 norm of the two test stations located at National Institute of Oceanography (NIO) and Karachi Port Trust (KPT) along the east southern coastal route of China Pakistan Economic Corridor (CPEC) project in Pakistan. Electrogalvanized mild steel test coupons were exposed for a period of 12 months from May 2014 to May 2015. Results indicated that for both NIO and KPT test stations the corrosivity category in term of corrosion rate (C5+) was not in agreement with the corrosivity category (C5) established by using the pollution category and time of wetness. Corrosion kinetic parameters n and correlation coefficient (R2) obtained for NIO were 1.58 and 0.98 and for KPT 1.43 and 0.95 respectively. Scanning electron microscopy/energy dispersive X‐ray spectroscopy (SEM/EDS) showed the presence of simonkolleite at NIO while zincite and hydrozincite at KPT. Fourier transform infrared (FTIR) spectroscopy showed that the typical corrosion products formed on both test stations were simonkolleite and hydrozincite. XRD showed the presence of zincite at both test stations and hydrozincite only at KPT. The primary goal of the study was to establish corrosivity category in accordance with ISO 9223 norm of the two test stations located at National Institute of Oceanography (NIO) and Karachi Port Trust (KPT) along the east southern coastal route of China Pakistan Economic Corridor (CPEC) project in Pakistan. Electrogalvanized mild steel test coupons were exposed for a period of 12 months from May 2014 to May 2015. [ABSTRACT FROM AUTHOR]

Zinc (Zn) has been proposed as an alternative metallic biodegradable material to support transient wound-healing processes. Once a Zn piece is implanted inside the organism the degradation will depend upon the physiological surrounding environment. This, by modulating the composition of the surface layers formed on Zn devices, will govern the subsequent interactions with the surrounding living cells (e.g. biocompatibility and/or antifungal behaviour). In silico simulation of an implanted Zn piece at bone-muscle interface or inside the bone yielded the preferential precipitation of simonkolleite or zincite, respectively. To study the impact of these surface layers in the in vitro behaviour of Zn biomaterials, simonkolleite and zincite where synthesised. The successful production of simonkolleite or zincite was confirmed by an extensive physicochemical characterization. An in vitro layer formed on the top of these surface layers revealed that simonkolleite was rather inert, while zincite yielded a complex matrix containing hydroxyapatite, an important bone analogue. When analysing the “anti-biofilm” activity simonkolleite stood out for its activity against an important pathogenic fungi involved in implant-device infections, Candida albicans . The possible physiological implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Layered double hydroxides are the 2D layered material also known as the anionic clays having the general formula [M1‐x2+Mx3+(OH)2]x+[Ax/n]n−.m H2O where different M2+ ions such as Zn2+, Ni2+, Mg2+, Co2+ and M3+ ions such as Al3+, Cr3+, Ga3+, In3+, Mn3+, Fe3+ are uniformly distributed and orderly prearranged in the brucite‐like sheets and various charge‐compensating anions (An−=CO32−, NO3−, Cl−, OH−) are present in their interlayer spaces along with the water molecules. During the synthesis of Zn−Al layered double hydroxides by non aqueous soft chemical method the strength of bases as well as the temperature influences immensely the hydrolysis of Zinc acetylacetonate (Zn(acac)2) and Aluminium acetylacetonate (Al(acac)3). Different bases such as sodium hydroxide (NaOH), piperidine, diethylamine and ammonia (NH3) was used and it was found that Zinc acetylacetonate (Zn(acac)2) directly forms Zincite (ZnO) phase without reacting with Aluminium acetylacetonate (Al(acac)3) at temperature of around 80oC. When the temperature was decreased to 0oC from room temperature as well as side by side the strength of bases were increased the formation of Zincite (ZnO) phases reduced. Thus, Zn−Al layered double hydroxide could only be synthesized at 0oC and in presence of stronger bases like sodium hydroxide (NaOH) and piperidine. The X‐ray diffraction analysis showed the presence of low intensity Zincite (ZnO) phases in Zn−Al layered double hydroxide synthesized in presence of sodium hydroxide (NaOH) which was absent in presence of piperidine. Zn−Al layered double hydroxide synthesized were further characterized by thermal analysis (TGA‐DTA), Infrared spectroscopy (FTIR), Scanning electron microscopic and energy dispersive X‐ray spectroscopic (SEM‐EDS) analysis, Brunauer–Emmett–Teller (BET) surface area and pore diameter analysis which showed their different characteristics as the base is changed. Zn−Al layered double hydroxide synthesized in presence of piperidine after thermal treatment at 800oC formed high surface area mesoporous flower platelet like Zinc‐Aluminium Oxide (ZnAl2O4) spinel which have surface area of 124.8 m2g−1 and mesopores of dimensions about 5–20 nm respectively. [ABSTRACT FROM AUTHOR]

The sulfidization mechanism of ZnO involving the interaction between S 2 and zincite (10 1 ¯ 0) surface was investigated by density functional theory (DFT) calculations. The geometry structures and electronic properties of atoms at the zincite surface layers before and after S 2 adsorption were thoroughly calculated. The results indicated that the oxygen atoms at the zincite surface were the dominating active site for the subsequent reaction. The S 2 could easily adsorb on the surface of zincite with an adsorption energy of −2.27 eV, followed by dissociation of Zn–O bond. The density of sate (DOS) analyses presented that the S 3p orbital from the S 2 and O 2p orbital at the mineral surface layer were obviously overlapped near the Fermi energy, suggesting that an intensive hybridization occurred between them. The Mulliken population results showed that both S atoms in S 2 could not only be oxidized, but also be reduced, resulting in the generation of SO 2 and ZnS. This study gave an insight into the interaction between S 2 and zincite surface at an atomic level and further enriched the sulfidization mechanism of ZnO at a high temperature. [ABSTRACT FROM AUTHOR]

Surface sulfidization behavior of smithsonite at high temperature was investigated by X-ray powder diffractometer (XRD) along with thermodynamic calculation, X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). The XRD and thermodynamic analyses indicated that the smithsonite was decomposed into zincite at high temperatures. After introducing a small amount of pyrite, artificial sulfides were formed at surface of the obtained zincite. The XPS analyses revealed that the sulfide species including zinc sulfide and zinc disulfide were generated at the zincite surface. The EPMA analyses demonstrated that the film of sulfides was unevenly distributed at the zincite surface. The average concentration of elemental sulfur at the sample surface increased with increasing of pyrite dosage. A suitable mole ratio of FeS 2 to ZnCO 3 for the surface thermal modification was determined to be about 0.3. These findings can provide theoretical support for improving the process during which the zinc recovery from refractory zinc oxide ores is achieved by xanthate flotation. [ABSTRACT FROM AUTHOR]

Due to distinguishing characteristics of nanoparticles (NPs) in terms of size, shape, chemical composition, transmittal and different applications, nanotechnology is considered as an interesting domain of research. Application of metallic NPs is important because of the diminution of dimensions and thus the unique thermal, optical and electronic properties. This research attempts to explore the synthesis of zinc oxide NPs. Zinc oxide NPs have been synthesized using cherry extract under different pH, temperature and concentration and then optimum conditions for the synthesis of them were determined. For further investigations, UV-Vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier infrared transformation spectroscopy (FTIR) were used. The solution containing zinc oxide NPs showed a major absorbance of 378 nm which confirmed the synthesis of zinc oxide NPs, and spherical morphology of NPs was observed in SEM images. Zinc oxide NP sizes were 6.5 and 20.18 nm which are obtained by UV-Vis spectra and XRD spectrum, respectively. Also, based on the FTIR spectra of the extract obtained before and after the synthesis, the existence of the reducing agents in herbal extract was confirmed. According to this study, the biological synthesis of NPs using plant extracts can be considered as a cost-effective and efficient method of biological synthesis of NPs and it could be an appropriate replacement to typical chemical methods for the synthesis of NPs. [ABSTRACT FROM AUTHOR]

Zinc is present in electric arc furnace dust (EAFD) mainly in two basic minerals, namely as franklinite ZnFe2O4 and/or zincite ZnO. While zincite is relatively reactive and easily treatable, franklinite is considerably refractory, which causes problems during EAFD processing. In this work EAFD containing 18.53% Zn was leached in water solution of ammonium carbonate. This leaching solution selectively leaches zincite, while franklinite is refractory and stable against leaching in this case. The temperature dependence of zinc leaching from EAFD was studied and the activation energy EA was determined by two methods: 1.) classically based on zinc chemical analyses from the leaching solution and 2.) by using of X-Ray diffraction qualitative phase analyses of leaching residues. The determined values of activation energies 37.41 and 38.55 kJmol-1 match perfectly, which show the excellent possibility of using X-Ray diffraction toward the study of leaching kinetics at properly chosen experimental conditions. The important result is the determination of the amount zincite and franklinite in EAFD, which is not possible by using of classical chemical methods. [ABSTRACT FROM AUTHOR]

Bacterial contamination poses a serious hazard for human health. The use of bactericidal materials, such as layered double hydroxides, might constitute a way to reduce the risk of diseases. In this work, ZnAl layered double hydroxides were synthesized by microwave irradiation at different pH values and various metal molar ratios to be tested against multi-resistant bacteria. The synthesis conditions were chosen to form, in some cases, a composite containing zincite (ZnO), as both materials, zincite as well as the layered double hydroxide, are well known to be efficient antimicrobials. Eucalyptus extracted oil, which is a bactericidal compound, was extracted from eucalyptus leaves and used to impregnate some layered double hydroxide–zincite composites. The materials were characterized by X-ray diffraction, infrared spectroscopy, nitrogen physisorption and scanning electron microscopy. The samples were tested against Staphylococcus sp. and Pseudomonas aeruginosa , which are multi-resistant bacteria. It was found that Zn/Al molar ratio, pH and inclusion of eucalyptus oil in the layered double hydroxides synthesis determined the bactericidal activity. The best performing samples were those containing eucalyptus oil, which, at very low concentrations, were able to kill Staphylococcus sp. and inhibit the Pseudomonas aeruginosa growth . [ABSTRACT FROM AUTHOR]

ZnO thin films containing different ratios of Ti metal were prepared by the DC/RF sputtering technique. XPS analysis showed the presence of Ti content in the range from 0.9 to 1.5 at.%, and Ti was existed as Ti4+ states. Zincite phase has been detected by XRD technique through all samples and the crystallite size, the strain, and the dislocation density were estimated. Surface morphology and roughness were examined by atomic force microscopy. Optical absorbance and optical band gap were measured and determined. The optical band gap is proposed to be direct and varied from 3.25 to 3.282 eV as the Ti content increase. Photoluminescence properties show a highly intense peak at 412 nm related to the transition from shallow donor level to valence band comes from the interface traps through the grain boundaries. [ABSTRACT FROM AUTHOR]

Fly ash from solid waste incineration plants is a source of a significant mass flow of Zn- and Pb-containing waste. Acidic leaching removes most heavy metals from fly ash, but leads to high concentrations of soluble salts in the solution, resulting in a saline solution enriched in heavy metals. Common treatment methods cause voluminous sludge that is mostly disposed of as hazardous waste and hence leads to a loss of Zn and other heavy metals. On a laboratory scale, precipitation experiments with 2000 mg/L Zn were performed to investigate the impact of salinity (0 to >70,000 mg/L Cl, 0 to 5400 mg/L SO4) and Pb concentration (0 to 800 mg/L) on the formation of mineral phases. The removal efficiency of Zn and Pb after alkalization of the solution was studied. Characterization of the precipitates showed that salinity has a significant impact on the phases produced. At a low salt concentration, zincite (ZnO) is formed. With increasing salinity, the higher concentration of chloride and sulfate increases the stability of various Zn sulphate hydroxides. At a medium salinity of 7000 mg/L, bechererite is predominantly formed, whereas a higher salinity leads to the formation of gordaite. Addition of low amounts of Pb enlarges the stability field of zincite to medium saline solutions but causes lower removal efficiency. The lower removal efficiency observed at low salinity increases at a higher salinity. In high saline solutions, high Pb concentrations (800 mg/L) are needed to form laurionite, a Pb-hydroxychloride phase. [ABSTRACT FROM AUTHOR]

Due to the strong effect of nanoparticles' size and surface properties on cellular uptake and bio‐distribution, the selection of coating material for magnetic core–shell nanoparticles (CSNPs) is very important. In this study, the effects of four different biocompatible coating materials on the physical properties of Fe3 O4 (magnetite) nanoparticles (NPs) for different biomedical applications are investigated and compared. In this regard, magnetite NPs are prepared by a simple co‐precipitation method. Then, CSNPs including Fe3 O4 as a core and carbon, dextran, ZnO (zincite) and SiO2 (silica) as different shells are synthesised using simple one‐ or two‐step methods. A comprehensive study is carried out on the prepared samples using X‐ray diffraction, vibrating sample magnetometry, transmission electron microscopy and Fourier transform infrared spectroscopy analyses. According to the authors' findings, it is suggested that carbon‐ and dextran‐coated magnetite NPs with high Ms have great potential in the application of magnetic resonance imaging contrast agents. Moreover, silica‐coated magnetite NPs with high coercivity are potentially suitable candidates for hyperthermia and ZnO‐coated Fe3 O4 is potentially suitable for photothermal therapy. [ABSTRACT FROM AUTHOR]

Blast furnace dust is a typical secondary resource produced in manufacturing iron. This substance contains many recyclable components, such as iron, lead, zinc, and carbon, which have not been properly utilized. Zinc is a dispersed component in blast furnace dust, but its volatility depends on its carrier minerals, such as hematite, coke, and silicate in descending order of zinc volatility. Volatilization is the necessary procedure of removing toxicity and recycling zinc from blast furnace dust. However, two critical limits exist: the amount of carbon in the residue and the amount of franklinite in the blast furnace dust. Zinc can be enclosed by the carbon grains according to kinetic analysis and energy dispersive spectrometer (EDS) tests. Therefore, the coke dosage should be controlled carefully to avoid carbon residue and increase the volatilization rate of zinc. Meanwhile, both franklinite and zincite are general zinc-bearing phases in the adopted dust, but neither can volatilize before being reduced to metallic form. Calculations show that the available reduction temperature of zincite is higher than that of franklinite. Nearly all the zinc in hematite and carbon is in the form of zincite and can be easily reduced in the heating process. However, the zinc in silicate mainly exists in the form of franklinite and is difficult to be reduced and volatilized, which explains the lower volatilization rate of zinc in silicate than in coke and hematite. In the last part of this investigation, the mineral phase and morphology of the volatiles obtained after fume reduction volatilization are tested for the first time to evaluate their potential application value. Only high-purity crystal zincite is found, which means that the volatiles can be used directly as high-grade zinc smelting materials without purification. [ABSTRACT FROM AUTHOR]

ZnO (zincite) coated magnetic particles were successfully prepared and characterized by different techniques (XRD, FE-SEM, EDX, and FTIR). The photocatalytic efficiency of the magnetic particles was assessed by their ability to degrade six fungicides in water exposed to solar irradiation. Magnetic particles composed of a silica undercoat beneath a ZnO coating (MSZPs) were more efficient than magnetic particles loaded with ZnO alone (MZPs) for catalysing the removal of these fungicides. The optimum mass ratio of SiO 2 to ZnO was about 1:2 because of almost complete coverage by ZnO surface coverage and the high photocatalytic degradation rates obtained for the studied fungicides, which was comparable to that obtained with ZnO nanopowder. However, in contrast to ZnO nanopowder, the photodissolution of Zn using MSZPs was low, with Zn 2+ concentration at the end of the experiment (0.75 mg L −1 ) below legally permitted levels in drinking water. In addition, the effect of initial concentration of fungicides was studied in order to know maximum degradation efficiency. Finally, the photodegradation activity of MSZPs was increased by the addition of Na 2 S 2 O 8 (250 mg L −1 ). Therefore, the tandem MSZPs/Na 2 S 2 O 8 provides an interesting method to degrade some organic pollutants in water. [ABSTRACT FROM AUTHOR]

ZnAl hydrotalcite-like compounds were modified through the incorporation of Zr +4 using molar ratios of Zr/Al(X)=0.0, 0.10 and 0.25. The synthesis of these materials was performed by the co-precipitation method and their physicochemical properties were characterized by XRD, UV-Vis-DRS, N 2 physisorption, TGA, and finally, the basic properties were analyzed by titration with benzoic acid and adsorption of methanol analyzed by FT-IR. It was found that 200ºC is the most appropriate activation temperature, since the catalytic activity of ZnAl-Zr(X) materials on the transesterification reaction was enhanced, obtaining FAME yields ranging from 68% to 82%. This high catalytic activity at low activation temperature (200ºC) was attributed to the presence of a mixture of the active phases: hydrotalcite, zincite, and hydrozincite; as well as the formation of Brönsted and Lewis basic sites when the hydrotalcite-type materials are dehydrated. In addition, it was possible to calculate the apparent reaction rate constants by means of a simplified lumped first-order reaction model. The reaction rate constant for the ZnAl-Zr(0.25) catalyst was 12.4 x10 -3 L/g cat .min which is 1.5 times greater than that of the catalyst without Zr. [ABSTRACT FROM AUTHOR]

The electronic structures of zincite Pb-modulated bulk and thin-films were studied via X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) techniques. Both XPS data and DFT-calculations allowed the derivation of two different Pb-embedding scenarios into the ZnO-hosts. These included the high-interaction mode of Pb-impurity with initial zinc-oxygen host-lattice for the bulk morphology, accompanied with low Pb-metal losses; and the low-interaction mode for thin-films, where there was intake of Pb-impurities into the hollows of the surface. Despite dissimilar mechanisms of Pb-impurity accumulation and distribution in the bulk and thin-films zincite host-matrices, the strong Pb 4f — Zn 3s and Pb 5d — O 2s overlapped ambiguity contribution to the appropriate core-level structure and valence bands was established by XPS analysis and reproduced with the help of DFT-calculations. It was shown that the microscopic structure of the embedded lead-impurity played a crucial role in the Pb ion-beam stimulated synthesis of secondary lead-oxygen phases via large-area defect fabrication, and the difference among zincite and wurzite polymorphs played almost no role in this case. [ABSTRACT FROM AUTHOR]

Gem-quality synthetic zincite from Poland, an industrial by-product of zinc oxide processing, has been available in the market since the early 1980s. In this investigation, conventional gemological methods, spectroscopic techniques, and advanced analytical testing were carried out on 10 rough and faceted samples. The chromophore manganese (Mn), which is significant in natural zincite and can reach 1 wt.% MnO, appears to be negligible in by-product crystals. These crystals also appear to have low to insignificant levels of other potential chromophores such as iron and copper. Inclusions matching previously reported oval and "tadpole-like" inclusions in Polish synthetic zincite were observed and tested by Raman and IR spectroscopy. These inclusions were identified as carbon-bearing material, possibly belonging to soot and/or gases captured during the growth of the synthetic zincite host. [ABSTRACT FROM AUTHOR]