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A novel phosphorus-free PASP–ED2A antiscalant exhibits good scale inhibition performance against calcium scale at a low concentration or a high temperature, better than that of PASP.

With the growing interest in developing miniaturized thermoelectric devices, there has been a strong demand in preparing thermoelectric thin films with high electrical conductivity and large power factors, hence ensuring the miniaturized devices have large cooling capacity and large output powers. This work demonstrated the preparation of intermetallic YbAl3 thin films through a double-target magnetron co-sputtering technique and a subsequent annealing treatment. It was revealed that the subsequent heat treatment of thin films plays a critical role in achieving crystalline, stoichiometric, and nanostructured YbAl3 thin films. Benefiting from the significantly improved crystallinity and stoichiometry, the optimized YbAl3 thin films exhibit extraordinarily high electrical conductivity reaching 1.7 × 106 S m−1 and large power factors around 7.4 mW m−1 K−2. The figure of merit ZT of the annealed thin films is comparable with that of the bulk materials, showing their potential use in miniaturized thermoelectric devices.

Cadmium selenium (CdSe) quantum dots (QDs) were synthesized using Saccharomyces cerevisiae (ATCC9763) as a biomatrix cultured with 5 mmol L−1 Na2SeO3 and 1 mmol L−1 CdCl2. Five decisive factors in the biomanufacture of CdSe QDs in S. cerevisiae were investigated and optimized, including the time point of adding Na2SeO3, the optimal concentrations of selenite and cadmium, and the incubating duration of selenite and cadmium with yeast cells respectively. By exploiting two dependent metabolic pathways in an appropriate procedure, CdSe QDs were obtained simply with controllable particle size and tunable fluorescence emission. With the help of an effective extracting method, the maximum emission peaks of different isolated QDs had been further detected, with adjustable wavelengths ranging from 506 nm (green) to 562 nm (yellow). The following in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the biocomposed CdSe QDs had much lower cytotoxicity compared with hydrothermally synthesized thioglycolic acid (TGA)-capped CdSe and TGA capped-CdTe. By the advantages of the operational protocol, these findings exhibited the potential of an uncomplicated biosynthetic method which is capable of producing easily detectable, environment-friendly and low toxic inorganic nanoparticles with easy access of raw materials.

Ammonia-modified graphene nanosheets (AMGNSs)/epoxy nanocomposites were prepared by using a facile blend method. Graphene nanosheets (GNSs) were modified with aqueous ammonia (NH3·H2O) and hydrogen peroxide (H2O2), to obtain amine (–NH2) functionalized GNSs and to enhance the bonding between the GNSs and epoxy resin matrix. The effects of the AMGNSs on the static and dynamic mechanical properties of the nanocomposites were investigated. The results indicated that the tensile and flexural strength and modulus of the AMGNS/epoxy nanocomposites first increased and then decreased with increasing addition of AMGNSs. The addition of 0.5 wt% AMGNSs improved the tensile strength and flexural modulus of the pristine epoxy by 27.84% and 7.75%, respectively. Meanwhile, the addition of 0.1 wt% AMGNSs improved the tensile modulus and flexural strength of the pristine epoxy by 14.16% and 94.38%, respectively. The reinforcing effect of the AMGNSs in enhancing the impact properties of the epoxy nanocomposites was also examined. It was demonstrated that the amine-functionalization of GNSs with ammonia had an obvious effect on the mechanical performances of epoxy matrix nanocomposites.

Robust oxygen ion conducting membranes based on doped ceria oxides can be used as oxygen permeation membranes with a short circuit to provide the required electronic conduction. Previous methods have coated both surfaces of the ion conducting electrolyte membrane with expensive noble metals as the electronic conducting phase to allow the electron shuttling required for oxygen reduction and oxidation to take place between the two membrane surfaces. During operation of the membrane, the atmosphere on the two sides of the membrane is different. The feed side is exposed to air, whereas the permeated side may be exposed to CO2 or reducing gases such as CH4 or H2. At high operating temperatures, such exposure to different gases requires the use of different materials to prepare the membranes, giving opportunities for further optimisation and the reduction of costs. In this work, a novel Ce0.9Gd0.1O2−δ membrane coated on the surface exposed to air with a cost-effective mixed conductive layer of Ba0.5Sr0.5Co0.8Fe0.2O3−δ was developed to deliver a highly stable oxygen flux for use in clean energy applications or as a membrane reactor for chemical synthesis. The membrane coated with Ba0.5Sr0.5Co0.8Fe0.2O3−δ improved the flux of oxygen compared with membranes coated with pure Ag. A triple phase boundary theory is put forward to explain the observed improvement in the oxygen flux.

Calcined ZnAl- and Fe3O4/ZnAl–layered double hydroxides (ZnAl–CLDH and Fe3O4/ZnAl–CLDH) were used as adsorbents to evaluate the uptake properties for Cr(VI) removal from aqueous solution by batch equilibrium experiments. The XRD, FTIR and TEM results showed that the calcined ZnAl–LDH and Fe3O4/ZnAl–LDH recovered layered structures according to the memory effect of hydrotalcite. Optimized conditions of Cr(VI) adsorption were obtained: 2.0 g L−1 adsorbent, initial solution pH of 3.0 and contact time of 60 min. The kinetic data was described better by a pseudo-second-order kinetic equation. The adsorption isotherms had a good fit with Langmuir and Freundlich models. Thermodynamic analyses indicated that the adsorption process was endothermic and spontaneous in nature. The adsorption mechanisms involved the reconstruction of LDHs, surface complexation, anion exchange and physical adsorption. The higher adsorption capacities of the calcined products suggested that the ZnAl–CLDH and Fe3O4/ZnAl–CLDH were potential adsorbents for Cr(VI) removal from water and wastewater. Moreover, the magnetic Fe3O4/ZnAl–CLDH can be easily separated using a magnet after the adsorption process.

Bianthrones have occurred widely in drug and material developments, but the stereochemistry remains in chaos so far due to the meso, racemic, and axis-rotating phenomena. Based on the computational and experimental results, an effective rule to distinguish between cis and trans bianthrones by H-1 NMR is concluded, which applies to both homo- and heterobianthrones.

We herein report the large-scale synthesis of Bi2Te3−xSex (0.6 ≤ x ≤ 0.75) nanoplatelets through a hydrothermal method and subsequent spark plasma sintering. The effect of selenium alloying and the spark plasma sintering temperature on the thermoelectric properties of the Bi2Te3 nanostructured bulk materials were investigated. The results indicate that compared to samples fabricated in an autoclave, preparing Bi2Te3−xSex in glass beaker with suitable Se alloying and appropriate sintered temperature is an efficient way to reduce the lattice thermal conductivity due to a large number of Bi2TeO5 nanodots with sizes of around 10 nm. Meanwhile, a decrease in electrical resistivity due to increase in carrier mobility and an enhancement of the Seebeck coefficient attribute to decrease in carrier concentration were observed. As a result, the thermoelectric figure-of-merit, ZT, is significantly improved and the maximum value reaches 0.96 for Bi2Te2.25Se0.75 at 490 K.