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Because of the high costs and environmental impacts of peat and chemical fertilizers, the search for sustainable alternatives is increasing. Posidonia-based compost (C) has been widely tested as a growing media, while the combination with decontaminated dredged sediments (S) has only recently been studied. Moreover, little information is available on the relationship between plants and growing media. In this work, the suitability of growing media (CS) composed of 100% C, 70% C + 30% S and 30% C + 70% S were investigated compared to peat, for ornamental plants (Elaeagnus macrophylla, Photinia × fraseri and Viburnum tinus). Plant growth, physiological, nutritional and antioxidant responses were also investigated. The CS were compliant with current legislation on growing media. The Cu (+60%; +70%), Mg (+11%; +23%) and Ca (+66%; +72%) concentrations were higher in CS with 30% and 70% of S, respectively, than peat. The plants growing in CS had lower antioxidant activities than those on peat, suggesting a better plant tolerance to abiotic stress. In conclusion, the use of CS growing media, especially those with 30% and 70% of S, can be a valuable strategy to replace peat and reduce the application of fertilizers. [ABSTRACT FROM AUTHOR]

The data presented has to do with identifying the various phases arising during the synthesis of the Y-type hexaferrite series Ba0.5Sr1.5Zn2-xNixFe12O22 by auto-combustion that we deem important for their microstructural and magnetic properties. The data and the related analyses support the research paper “Ni-substitution effect on the properties of Ba0.5Sr1.5Zn2-xNixFe12O22 powders” [1]. Thus, the parameters are presented of the phases appearing after auto-combustion and after the initial annealing at 800 °C, namely, crystal cell and crystallite size. Also, additional data are provided obtained by EDS concerning the Ba:Sr:Zn:Ni:Fe ratio in Ba0.5Sr1.5Zn2-xNixFe12O22 (x = 0.8, 1, 1.5) samples synthesized at 1170 °C for 10 h. The data can be used as a reference in establishing how the phases distinguished during the initial process of auto-combustion affect the Ba0.5Sr1.5Zn2-xNixFe12O22 powders, which are candidates for room-temperature multiferroic materials. The data have not been published previously and are made available to permit critical or further analyses.

This work is pertaining to the synthesis of fine magnesium aluminate spinel (MgAl _2 O _4 ) powders of varied trivalent:bivalent cation ratio along line of homogeneity of the solid solution (MgO. xAl _2 O _3 , x = 1, 1.25, 1.50, 1.75, and 2) via gel combustion method. Magnesium- and aluminum- nitrate were used as the oxidants in combustion reaction fuelled by urea in combination with stoichiometric formaldehyde solution acting as reductant. Synthesized powders were characterized in terms of microscopic analysis and optical absorbance measurements. The cation ratio, through a change in gel structure influences the nature of crystallization of the product, while on the other hand does not affect grain shapes and sizes. Distinct enhancement in both absorption intensity and the corresponding estimated energy band gap has been observed against increasing excess than stiochiometric alumina concentrations. Evaluated optical band gaps were widened in proportion to the Al: Mg ratio which may be attributed to Burstein-Moss effect in consequence of substitutional insertion of introduced Al ^3+ ions in spinel lattices.

Highlights • Local measurements of magnetic circular dichroism, atomic arrangement, cation order, chemical state and elemental distribution from the very same region provide an improved understanding of structure-property relationships at the nm scale in double perovskites with different structural complexities. • Antiferromagnetic Fe3+-O2−-Fe3+superexchange interactions arising from an excess of Fe suppress the magnetic circular dichroism signal from Fe cations in ordered Sr 2 [Fe][Fe 1/5 Re 4/5 ]O 6 , when compared with ordered Sr 2 [Fe][Re]O 6. • Dominant Fe3+-O2−-Fe3+antiferromagnetic coupling in disordered Sr[Fe 4/5 Re 1/5 ]O 3 leads to a decrease in magnetic circular dichroism signal down to the noise level. Abstract Superexchange-based magnetic coupling of the two B -site cations in rock-salt-ordered double perovskite oxides is extremely sensitive to the cation ratio and degree of order. However, as a result of the limited spatial resolution of most magnetic characterization techniques, it is challenging to establish a direct relationship between magnetic properties and structure in these materials, including the effects of elemental segregation and cation disorder. Here, we use electron energy-loss magnetic chiral dichroism together with aberration-corrected electron microscopy and spectroscopy to record magnetic circular dichroism (MCD) spectra at the nm scale, in combination with structural and chemical information at the atomic scale from the very same region. We study nanoscale phases in ordered Sr 2 [Fe][Re]O 6 , ordered Sr 2 [Fe][Fe 1/5 Re 4/5 ]O 6 and disordered Sr[Fe 4/5 Re 1/5 ]O 3 individually, in order to understand the role of cation ratio and order on local magnetic coupling. When compared with ordered Sr 2 [Fe][Re]O 6 , we find that antiferromagnetic Fe3+-O2−-Fe3+superexchange interactions arising from an excess of Fe suppress the MCD signal from Fe cations in ordered Sr 2 [Fe][Fe 1/5 Re 4/5 ]O 6 , while dominant Fe3+-O2−-Fe3+antiferromagnetic coupling in disordered Sr[Fe 4/5 Re 1/5 ]O 3 leads to a decrease in MCD signal down to the noise level. Our work demonstrates a protocol that can be used to correlate crystallographic, electronic and magnetic information in materials such as Sr 2 Fe 1+ x Re 1- x O 6 , in order to provide insight into structure-property relationships in double perovskite oxides at the atomic scale. [ABSTRACT FROM AUTHOR]

In present work, the Fe 3 O 4 magnetic nanoparticles were successfully synthesized by coprecipitation method. In order to study the effects of influential factors on the structural and magnetic properties of particles, the experimental runs were designed using response surface methodology (RSM) based on central composite design (CCD), while the reaction temperature, Fe 2+ /Fe 3+ cation ratio, and pH of reaction were defined as effective factors on the two responses include the amounts of crystallinity degree and saturation magnetization ( M s ). The investigation of structural, magnetic, and microstructural properties of particles were carried out by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and dynamic light scattering (DLS) and transmission electron microscopy (TEM) analyses. As a result, the predictive quadratic models were fitted on the both responses while the R 2 values were more than 0.97 for both models. The highest amounts of both responses (crystallinity degree: 88.07% and M s : 65.801 emu/g) are presented when the reaction temperature, cation ratio, and pH amounts are equal to 90 °C, 0.60, and 10.5, respectively. Finally, the TEM results show the particles with size of about 10 nm and narrow size distribution. [ABSTRACT FROM AUTHOR]

Generally, the statistical methods are defined as appropriate techniques to study the processes trends. In current research, the Fe 3 O 4 superparamagnetic nanoparticles were synthesized by coprecipitation method. In order to investigate the size properties of synthesized particles, the experimental design was done using central composite method (CCD) of response surface methodology (RSM) while the temperature, pH, and cation ratio of reaction were selected as influential factors. After particles synthesis based on designed runs, the different responses such as hydrodynamic size of particles (both freeze dried and air dried), size distribution, crystallite size, magnetic size, and zeta potential were evaluated by different techniques i.e. dynamic light scattering (DLS), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). Based on these results, the quadratic polynomial model was fitted for each response that could predict the response amounts. In following, the study of factors effects was carried out that showed the temperature, pH, and their interactions had higher effectiveness. Finally, by optimizing, it was clear that the minimum amounts of particle size (10.15 nm) and size distribution (13.01 nm) were reached in the minimum temperature (70 °C) and cation ratio (0.5) amounts and maximum pH amount (10.5). Moreover, the characterizations showed the particles size was about 10 nm while the amounts of M s , H c , and M r were equal to 60 (emu/g), 0.2 (Oe) and 0.22 (emu/g), respectively. [ABSTRACT FROM AUTHOR]

Sweet pepper plants (Capsicum annuum L.) were cultivated hydroponically under different nutrient cation ratios at both high potassium (K)/calcium (Ca) (12:2) or magnesium (Mg)/Ca (4:2) ratios, compared with half strength Hoagland's solution (K:Ca:Mg; 3.5:2:0.5). Additionally, antitranspirant (Pinolene) was sprayed every fortnight to the aerial part of the plant at 1% (v/v). The antitranspirant (AT) did not affect dry weight accumulation in the leaves, stems, roots, total plant leaf area, or leaf dry weight percentage. Net carbon dioxide (CO2) assimilation was not impaired by the AT but the water uptake was reduced significantly independent of the nutrient solution used. The AT did not affect the cation uptake but high Mg significantly reduced Ca concentration in leaves, stems, and fruits, whilst high K had an effect only in old leaves and fruits. The AT reduced fructose and glucose concentration in the leaves but no effect was found in the fruits. Fruit yield was not affected by AT, but it was increased when plants were grown with high Mg/Ca. The percentage of blossom-end rot was reduced with the AT, whilst it was increased with the solutions having high K/Ca or high Mg/Ca. The AT significantly reduced fruit firmness in high Mg/Ca and control solution but no effect was found for fruit color, shape index, total soluble solids, or pericarp thickness. [ABSTRACT FROM AUTHOR]

Na+ and Cs+ ions have always co-existed in natural Cs+-bearing soil environments, and a vast number of research works have investigated their adsorption at clay surface. However, in fact, which one has a stronger adsorption affinity and what is the underlying mechanism are still controversial. In the present work, adsorption of Cs+/Na+ with five different ratios (ϕ1 ~ ϕ5) at the surface of illite was systematically investigated, using molecular dynamics simulations. Site-specific adsorption phenomenon occurred for both Cs+ and Na+. Cs+ ions have three adsorption sites (T A , T B , and T C) in the siloxane cavity while Na+ ions have one more that close to the substitution site (T D). Though Na+ had a substantially stronger adsorption affinity compared to Cs+ at T A /T B /T C sites, its adsorption at T D site was significantly weaker. Considering the specificity of different adsorption site, the total effective adsorption affinity increased as Na+ (ϕ5) < Cs+ (ϕ1) based on their pure solutions while increased as Cs+ < Na+ when they were mixed together (ϕ2 ~ ϕ4). Therefore, the relative adsorption affinity of Cs+ and Na+ should be further measured by considering the coupling effect of adsorption site and Cs+/Na+ ratio, besides the effect of ionic radius and hydration energy. It is likely that the common understanding on the adsorption of Cs+ and Na+ relies too much on pure system. In this way, this work provided a new clue to understand the affinity of mixed cations at the clay-water interface, which may be useful for assessing the transport and bioavailability of elements in soils. • The adsorption of Cs+/Na+ at illite surface was investigated using MD simulation. • Site specific adsorption phenomenon was significantly clear for both Cs+ and Na+. • Adsorption affinity Cs+ > Na+ may be reversed by changing Cs+/Na+ ratio. • Coupling effect of adsorption site and Cs+/Na+ ratio on cation adsorption was measured. [ABSTRACT FROM AUTHOR]

The data presented has to do with identifying the various phases arising during the synthesis of the Y-type hexaferrite series Ba 0.5 Sr 1.5 Zn 2-x Ni x Fe 12 O 22 by auto-combustion that we deem important for their microstructural and magnetic properties. The data and the related analyses support the research paper "Ni-substitution effect on the properties of Ba 0.5 Sr 1.5 Zn 2-x Ni x Fe 12 O 22 powders" [1]. Thus, the parameters are presented of the phases appearing after auto-combustion and after the initial annealing at 800 °C, namely, crystal cell and crystallite size. Also, additional data are provided obtained by EDS concerning the Ba:Sr:Zn:Ni:Fe ratio in Ba 0.5 Sr 1.5 Zn 2-x Ni x Fe 12 O 22 (x = 0.8, 1, 1.5) samples synthesized at 1170 °C for 10 h. The data can be used as a reference in establishing how the phases distinguished during the initial process of auto-combustion affect the Ba 0.5 Sr 1.5 Zn 2-x Ni x Fe 12 O 22 powders, which are candidates for room-temperature multiferroic materials. The data have not been published previously and are made available to permit critical or further analyses., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2020 The Author(s).)

A novel CH4 gas sensor based on the nanocomposites and mixed oxides of Sn, In, and Ti, workable at near room temperature, were developed. The binary and ternary oxides were prepared by a chemical controlled step precipitation method and mixed route. The preparation parameters-salt concentration, cation ratio, precipitation pH, and aging time-have been optimized, and their optimal value were 0.05 M, 20% Ti: 20% In: 60% Sn, pH=8.0 and aged 24 h, respectively. The appropriate calcinations temperature for precursor and mixture were 600 degC 4 h and 700 degC 2 h. The performance and structure of the materials were characterized by TEM, BET, TG-DTA, XRD, TPD, and XPS. The sensing tests showed that these nanomaterials exhibited high sensitivity and selectivity for CH4 and their sensing properties depended on the oxide composition, calcinations temperature, operating temperature, and gas concentration. The gas-sensing mechanism of the sensor was also discussed by TPD and XPS analysis [ABSTRACT FROM PUBLISHER]

We present electrical properties of Schottky barrier diodes on room-temperature deposited amorphous zinc-tin-oxide (ZTO) with Zn/(Zn + Sn) contents between 0.12 and 0.72. A combinatorial approach with continuous composition spread pulsed laser deposition is used to achieve the wide range of compositions with four samples each on 50 × 50 mm 2 glass substrates. The Schottky barrier contacts were fabricated by the reactive direct-current sputtering of platinum. Best diode properties (rectification ratio S V = 2.7 × 10 7 , ideality factor η = 1.05, and effective barrier height ϕ B,eff = 1.25 eV) are obtained for a composition of 0.63 Zn/(Zn + Sn). Aging on the timescale of days and months is observed that leads to improved device properties (higher rectifications and lower ideality factors). In particular, the diodes with the lowest performance in the as-prepared state show the biggest improvements. The best diode properties after the aging process (S V = 3.9 × 10 7 , η = 1.12, and ϕ B,eff = 1.31 eV) were also observed for 0.63 Zn/(Zn + Sn).