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Supersaturated alloys can exhibit superior properties and electrodeposition is a cost-effective and versatile technique to produce them. In this review, the chemical, mechanical and structural properties of supersaturated alloys are discussed, and connections with metallic glasses and high entropy alloys are also exposed. After discussing mechanisms causing supersaturation in electrodeposited alloys, an overview of the most important electrodeposited metastable alloys is provided, showing that they are mainly used as protective coatings able to improve corrosion resistance and tribological performance of a large variety of industrial components. Composition of the electrolytic baths and deposition parameters are also considered and discussed. [ABSTRACT FROM AUTHOR]

Supersaturated alloys can exhibit superior properties and electrodeposition is a cost-effective and versatile technique to produce them. In this review, the chemical, mechanical and structural properties of supersaturated alloys are discussed, and connections with metallic glasses and high entropy alloys are also exposed. After discussing mechanisms causing supersaturation in electrodeposited alloys, an overview of the most important electrodeposited metastable alloys is provided, showing that they are mainly used as protective coatings able to improve corrosion resistance and tribological performance of a large variety of industrial components. Composition of the electrolytic baths and deposition parameters are also considered and discussed.

In the scope of supersaturated semiconductors for infrared detectors, we implanted Si samples with Ti at high doses and processed them by rapid thermal annealing (RTA) to recover the crystal quality. Also, for comparative purposes, some samples were processed by pulsed-laser melting. We measured the electronic transport properties at variable temperatures and analyzed the results. The results indicate that, for RTA samples, surface layers with a high Ti concentration have negligible conductivity due to defects. In contrast, the implantation tail region has measurable conductivity due to very high electron mobility. This region shows the activation of a very shallow donor and a deep donor level. While deep levels have been previously reported for Ti in Si, such a shallow level has never been measured, and we suggest that it originates from Ti-Si complexes. Finally, a decoupling effect between the implanted layer and the substrate seems to be present, and a bilayer model is applied to fit the measured properties. The fitted parameters follow the Meyer–Neldel rule. The role of the implantation tails in Si supersaturated with Ti is revealed in this work. [ABSTRACT FROM AUTHOR]

Conventionally, bulk WC and Cr 3 C 2 -based carbide compositions have been used independently of each other. However, recent investigations have begun to explore combining these carbides together within the same composite/hard metal coating system. This work explored the diversity of phases produced in the coatings from a 42 wt% WC-42 wt% Cr 3 C 2 –16 wt% Ni powder sprayed under "low", "medium" and "high" thermal input conditions using high velocity oxygen-fuel (HVOF), an argon‑helium (Ar He) plasma and an argon‑hydrogen (Ar H 2) plasma respectively. The thermally driven solid-state transformations in the coatings were investigated as a function of carbide dissolution/decomposition, using differential scanning calorimetry (DSC). All coatings exhibited a well defined exothermic peak attributed to the transformation of the metastable supersaturated Ni-alloy and WC 1-X phases in the as-sprayed coatings, into the equilibrium Ni alloy and a mix of the intermediate metastable carbide phases β-W 2 C and Cr 3 C 2 - Y. At higher temperatures the metastable compounds transformed to the equilibrium phases of ε-W 2 C and Cr 3 C 2. A defining feature of the XRD analysis was the significant shift in lattice positions of all phases, indicating substitutional alloying. The mechanisms of phase formation are discussed. • A WC-Cr 3 C 2 -Ni composite powder was sprayed using HVOF and Plasma thermal spraying. • Exothermic DSC peak from 680 to 760 °C attributed to precipitation of dissolved phases. • HVOF coating formed WC, ε-W 2 C and Cr 3 C 2 - Y at 650 °C, and Cr 3 C 2 at higher temperature. • Negligible change in Plasma coating Ni alloy, WC 1-X and β-W 2 C phases up to 760 °C. • Above 760 °C, the saturated Ni alloy and WC 1-X transformed to form Cr 3 C 2 and ε-W 2 C. [ABSTRACT FROM AUTHOR]

Abstract: Photovoltaic solar cells based on the intermediate band (IB) concept could greatly enhance the efficiency of future devices. We have analyzed the electrical and photoconductivity properties of GaP supersaturated with Ti to assess its suitability for IB solar cells. GaP:Ti was obtained by ion implantation followed by pulsed‐laser melting (PLM) using an ArF excimer laser. It was found that PLM energy densities between 0.35 and 0.55 J/cm2 produced a good recovery of the crystalline structure of GaP (both unimplanted and implanted with Ti), as evidenced by high mobility measured values (close to the reference GaP). Outside this energy density window, the PLM failed to recover the crystalline structure producing a low mobility layer that is electrically isolated from the substrate. Spectral photoconductivity measurements were performed by using the van der Pauw set up. For GaP:Ti a significant enhancement of the conductivity was observed when illuminating the sample with photon energies below 2.26 eV, suggesting that this photoconductivity is related to the presence of Ti in a concentration high enough to form an IB within the GaP bandgap. The position of the IB was estimated to be around 1.1 eV from the conduction band or the valence band of GaP, which would lead to maximum theoretical efficiencies of 25% to 35% for a selective absorption coefficients scenario and higher for an overlapping scenario. [ABSTRACT FROM AUTHOR]

Power ultrasound-assisted crystallization, which is also called sonocrystallization, is a novel and effective method for enhancing crystallization processes compared to conventional processes. In both supercooled and supersaturated crystallization, power ultrasound can accelerate the nucleation rate and better control the formation and growth of crystals. Due to its high efficiency, power ultrasound has been applied in many fields. In this review, studies published in recent years on effects of power ultrasound in both supercooled and supersaturated crystallization processes are discussed, with focus on the widely accepted crystallization mechanism and modeling. The applications of power ultrasound in liquid ice crystallization, ice cream manufacture, fruit and vegetable preservation and sugar and food supersaturated crystallization are summarized, and challenges and trends for further development of the technology are presented. [ABSTRACT FROM AUTHOR]

Purpose: To develop a liposomal system with high drug loading (DL) for intravenous (i.v.) delivery of a poorly water-soluble basic drug, asulacrine (ASL). Methods: A thin-film hydration and extrusion method was used to fabricate the PEGylated liposomal membranes followed by a freeze and thaw process. A novel active drug loading method was developed using ammonium sulphate gradient as an influx driving force of ASL solubilized with sulfobutyl ether-β-cyclodextrin (SBE-β-CD). DL was maximized by optimizing liposomal preparation and loading conditions. Pharmacokinetics was evaluated following i.v. infusion in rabbits. Results: Freeze-thaw resulted in unilamellar liposome formation (180 nm) free of micelles. Higher DL was obtained when dialysis was used to remove the untrapped ammonium sulphate compared to ultracentrifuge. The pH and SBE-β-CD level in the loading solution played key roles in enhancing DL. High DL ASL-liposomes (8.9% w/w, drug-to-lipid mole ratio 26%) were obtained with some drug 'bundles' in the liposomal cores and were stable in a 5% glucose solution for >80 days with minimal leakage (<2%). Surprisingly, following administration of ASL-liposomes prepared with or without SBE-β-CD, the half-lives were similar to the drug solution despite an increased area under the curve, indicating drug leakage from the carriers. Conclusions: High liposomal DL was achieved with multiple strategies for a poorly-water soluble weak base. However, the liposomal permeability needed to be tailored to improve drug retention. [ABSTRACT FROM AUTHOR]

Optimal designs depend upon a prespecified model form. A popular and effective model-robust alternative is to design with respect to a set of models instead of just one. However, model spaces associated with experiments of interest are often prohibitively large and so algorithmically generated designs are infeasible. Here, we present a simple method that largely eliminates this problem by choosing a small set of models that approximates the full set and finding designs that are explicitly robust for this small set. We build our procedure on a restricted columnwise-pairwise algorithm, and explore its effectiveness for two model spaces in the literature. For smaller full model spaces, we find that the designs constructed with the new method compare favorably with robust designs that use the full model space, with construction times reduced by orders of magnitude. We also construct designs that heretofore have been unobtainable due to the size of their model spaces. Supplementary material (available online) includes code, designs, and additional results. [ABSTRACT FROM PUBLISHER]

Hydraulic structures such as spillways or weirs with their water-air controlling mechanisms are not only important for their structural properties but also for their effects on downstream ecology. Tailwater depth is an important factor affecting dissolved oxygen transfer and aeration rates of spillways. In this study, effects of tailwater depths and discharge values on the aeration efficiencies of laboratory-model smooth and stepped spillways were investigated. Changes of tailwater depths affect the dissolved oxygen transfer rates and aeration efficiencies are affected more than 100%, resulting in supersaturated dissolved oxygen concentrations. Tailwater depth is a significant parameter in the design of the spillway and the stilling basin of dams. Therefore, this value should be estimated correctly. [ABSTRACT FROM AUTHOR]

A supersaturated Ni-10Ti alloy powder was produced from Ni and Ti elemental powders by solid state synthesis utilizing high energy mechanical alloying with times up to 5 h. Then, the milled powders were deposited on AISI 304 stainless steel substrate using air plasma spraying (APS) process. The microstructure and phase composition of the products were evaluated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results indicated that the coatings contain Ni-Ti supersaturated solid solution and small amounts of oxides. The microhardness value for the deposited layer was comparable to that of as-milled powder. Further investigation showed that the corrosion performance of Ni-10Ti coating was comparable to that of AISI 304 stainless steel substrate. [ABSTRACT FROM AUTHOR]

Water uptake by hygroscopic constituents of atmospheric particles has implications for climate and health. This article focuses on three topics related to calculating particle water uptake. First, an electrodynamic balance (EDB) is used to measure water activity for supersaturated binary KNO3 and KCl solutions. The EDB measurements for KNO3 confirm earlier predictions, while those for KCl confirm earlier measurements. Second, our earlier theory for the variation in mutual deliquescence relative humidity (MDRH) with temperature (T) is extended to double salt systems. The MDRH(T) equation for double salt systems reduces to the earlier equation under some conditions, and predictions for two systems are in reasonable agreement with solubility-based calculations. Finally, an approximate treatment of water uptake in the MDRH region (i.e., near the eutectic) is evaluated, and a new approach is developed that accounts for particle composition. The new approach represents predictions of a benchmark model well and eliminates most of the error associated with the earlier method. Although simple treatments of water uptake near the eutectic may introduce error into equilibrium calculations, their use can sometimes be justified based on inherent limitations of aerosol representations in chemistry-transport models. Results of this study can be used to improve calculations of water content in atmospheric aerosol models. [Copyright &y& Elsevier]

Abstract: The water activity (a w) of unsaturated and supersaturated trehalose solutions (and some sucrose solutions) was determined using a dew point hygrometer, and correlated using an equation originally proposed by Norrish [1966. An equation for the activity coefficients and equilibrium relative humidities of water in confectionery syrups. Journal of Food Technology, 1,25] for predicting water activity in binary non-electrolyte solutions. The a w lowering behaviour of trehalose was found to be almost identical to that of sucrose solutions at same concentrations; however, due to the lower solubility of trehalose the a w of their saturated solutions is higher than that of sucrose ones. The a w of saturated trehalose solutions at 20, 25, 30, 35 and 40°C was also determined and found to be between 0.953 and 0.928. These values agreed well with predictions made using a w data for trehalose solutions calculated at the solubility concentration at the various temperatures. [Copyright &y& Elsevier]

Abstract: Atmospheric aerosol models often calculate water uptake by particles based on information on salt deliquescence and electrolyte mixing rules. Therefore improvements in deliquescence predictions and in the water-activity relations used in mixing rules can improve estimates of size distributions. The primary goals of this work are to derive equations for the variation in the mutual deliquescence relative humidity (MDRH) with temperature (T) for a particle containing an arbitrary number of hydrated and anhydrous salts and to extend the range of validity of water–activity relations reported for binary solutions of KNO3, KCl, KBr, and K2SO4 to greater supersaturations. Equations for MDRH(T) are derived based on the equilibrium conditions that define deliquescence and the Gibbs-Duhem relation. MDRH is calculated from solubility data and the ZSR mixing rule to generate reference values for the equations and to evaluate their reliability. The ZSR mixing rule is also used to predict concentrations of KNO3, KCl, KBr, and K2SO4 in highly supersaturated binary solutions. Polynomial fits are presented that relate water activity to concentration for these solutions. The deliquescence equations derived here predict MDRH(T) for hydrate systems with sufficient accuracy for temperature excursions of about 25K. MDRH(T) usually follows the trend of DRH(T) for the most soluble salt in the system, while the temperature dependence of saturation concentration can be neglected for some salt systems. A linear temperature dependence for saturation concentration appears necessary to capture MDRH(T) for systems containing Ca(NO3)2·4H2O and CaCl2·6H2O. Consideration of deliquescence for a representative sea-salt system indicates that minor hydrated components have an important influence on the uptake of water by sea-salt particles and should be considered in equilibrium aerosol models. Results of this study improve estimates of water uptake by atmospheric particles containing hydrates and potassium salts. [Copyright &y& Elsevier]

In this study, we developed an ultrafine-grained W-20 wt%Cu composite with unique supersaturated solid solution (SSS) structure. This composite exhibits outstanding tensile properties: the tensile strength and elongation at room-temperature are 850 MPa and 9.3% respectively, and those at high-temperature (800 °C) are 200 MPa and 11.4% respectively. Meanwhile, it has excellent thermal performance with a coefficient of thermal expansion (CTE) of 7 × 10−6/K) and thermal conductivity (TC) of 220 W/mk. These exceptional comprehensive properties are attributed to the homogeneous microstructure and the satisfactory interface matching relationship of { [ 001 ] | | [ 1 ¯ 12 ] , (1 ¯ 30) s s s | | (2 ¯ 2 2 ¯) m a t r i x ; [ 001 ] | | [ 1 ¯ 12 ] , (310) s s s | | (220) m a t r i x }. This work provides a guideline for fabrication of composites with excellent comprehensive properties in immiscible systems. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline, supersaturated and metastable Al–Mg dendrites with stacks of smooth and rough globules were produced through electrodeposition. Rough globules always formed over the smooth ones. The smooth globules possessed face centered cubic (fcc)-Al(Mg) phase with ~20at.% Mg. The rough globules contained ~80at.% Mg and corresponded to hexagonal close packed (hcp)-Mg(Al) phase. Across the smooth-rough boundary a drastic jump in the composition from ~20 to ~80at.% Mg was observed in nanometer scale. The metastable equilibrium between the supersaturated fcc and hcp phases was explained using the estimated free energy change-composition (ΔG–x) curves. [Copyright &y& Elsevier]

A supersaturated NiTi(Al) alloy powder was produced from NiTi and Al powders by solid-state synthesis utilizing high-energy mechanical alloying with times up to 8 h. The microstructure and phase composition of the milling products were evaluated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results indicated that the diffraction lines corresponding to B2-NiTi shift toward higher angles with increasing milling time, which means that the lattice parameter of NiTi decreases and NiTi(Al) solid solution is formed. Further investigations showed that the lattice parameter of NiTi reaches a constant value after 8 h of milling, indicating that alloying of NiTi and Al is completed. [ABSTRACT FROM AUTHOR]

• Silica-lipid hybrids enhance oral bioavailability of abiraterone acetate. • Silica-lipid hybrids achieve 1.43-fold greater exposure than commercial Zytiga. • In vitro-in vivo correlation exists between lipolysis and pharmacokinetic studies. • The first report of a lipid-based formulation approach for abiraterone acetate. • The first report of abiraterone acetate oral pharmacokinetics in Sprague-Dawley rat. Abiraterone acetate (AbA) has an oral bioavailability of <10% due to its poor water solubility. Here we investigate the performance of silica-lipid hybrids (SLH) and supersaturated SLH (super-SLH) in improving oral bioavailability of AbA. Specifically, we investigate the influence of lipid type and AbA saturation level of the equilibrium solubility in the lipid (S eq), and explore in vitro-in vivo correlation (IVIVC). An oral pharmacokinetic study was conducted in fasted Sprague-Dawley rats. Suspensions of the formulations were administered via oral gavage at an AbA dose of 25 mg/kg. Plasma samples were collected and analyzed for drug content. SLH with a saturation level of 90% S eq enhanced the oral bioavailability of unformulated AbA by 31-fold, and super-SLH with saturation levels of 150, 200 and 250% S eq , enhanced the bioavailability by 11, 10 and 7-fold, respectively. In comparison with the commercial product Zytiga, SLH (90% S eq) increased the oral bioavailability 1.43-fold whereas super-SLH showed no improvement. A reasonable IVIVC existed between the performance of unformulated AbA, SLH and super-SLH, in the in vitro lipolysis and in vivo oral pharmacokinetic studies. SLH and super-SLH significantly enhanced the oral bioavailability of AbA. Additionally, supersaturation of SLH improved drug loading but did not correlate with enhanced AbA bioavailability. [ABSTRACT FROM AUTHOR]