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Thiospinels, such as CoNi 2 S 4 , are showing promise for numerous applications, including as catalysts for the hydrogen evolution reaction, hydrodesulfurization, and oxygen evolution and reduction reactions; however, CoNi 2 S 4 has not been synthesized as small, colloidal nanocrystals with high surface-area-to-volume ratios. Traditional optimization methods to control nanocrystal attributes such as size typically rely upon one variable at a time (OVAT) methods that are not only time and labor intensive but also lack the ability to identify higher-order interactions between experimental variables that affect target outcomes. Herein, we demonstrate that a statistical design of experiments (DoE) approach can optimize the synthesis of CoNi 2 S 4 nanocrystals, allowing for control over the responses of nanocrystal size, size distribution, and isolated yield. After implementing a 2 5-2 fractional factorial design, the statistical screening of five different experimental variables identified temperature, Co:Ni precursor ratio, Co:thiol ratio, and their higher-order interactions as the most critical factors in influencing the aforementioned responses. Second-order design with a Doehlert matrix yielded polynomial functions used to predict the reaction parameters needed to individually optimize all three responses. A multiobjective optimization, allowing for the simultaneous optimization of size, size distribution, and isolated yield, predicted the synthetic conditions needed to achieve a minimum nanocrystal size of 6.1 nm, a minimum polydispersity (σ/ d̅ ) of 10%, and a maximum isolated yield of 99%, with a desirability of 96%. The resulting model was experimentally verified by performing reactions under the specified conditions. Our work illustrates the advantage of multivariate experimental design as a powerful tool for accelerating control and optimization in nanocrystal syntheses.

Background: Vitamin D deficiency is common in peritoneal dialysis (PD) patients, so its supplementation has been advocated as potentially beneficial., Methods: Double-blind, placebo-controlled, randomized clinical trial. Subjects on PD treated with high calcium peritoneal dialysate (Ca 3.5 mEq/l) and serum levels of 25-hydroxi vitamin D (25D) < 20 ng/ml were randomized to receive cholecalciferol (4800 IU/daily) or placebo for 16 weeks. The outcome measures were the effects on the osteogenic biomarkers osteoprotegerin (primary endpoint), intact fibroblast growth factor-23 (iFGF23), osteocalcin, osteopontin, iPTH, 1,25-dyhydroxivitamin D (1,25D), and interleukin-6., Results: Fifty-eight subjects were randomly assigned. Baseline characteristics were similar in both groups. Cholecalciferol supplemented subjects had a significant increase in serum 25D (from 11.4 ± 5.0 to 28.3 ± 10.3 ng/ml), 1,25D and iFGF23 compared with placebo group. iFGF23 levels increased an average of 10,875 pg/ml per month (95% CI 11,778-88,414) in the cholecalciferol group and was unchanged in the placebo group (2829 pg/ml, 95% CI - 2181 to 14,972). Extremely high iFGF23 levels (> 30,000 pg/ml) were observed in 74% of subjects receiving cholecalciferol although iFGF23 returned to baseline values after 32 weeks of withdrawal. The observed changes in iFGF23 correlated with 1,25D levels and were not modified by other variables. No difference was observed between groups in osteoprotegerin or other osteogenic biomarkers levels., Conclusions: Cholecalciferol supplementation increases serum 25D levels in subjects on PD exposed to high calcium dialysate, yet it induces an exponential increase of iFGF23 in most patients, which disappear after withdrawal of supplementation and may be a major concern for this maneuver.

A polymeric membrane-supported catalyst with immobilized gold nanoparticles (AuNPs) was prepared through the extraction and in situ reduction of Au III salts in a one-step strategy. Polymeric inclusion membranes (PIMs) and polymeric nanoporous membranes (PNMs) were tested as different membrane-support systems. Transport experiments indicated that PIMs composed of cellulose triacetate, 2-nitrophenyloctyl ether, and an aliphatic tertiary amine (Adogen 364 or Alamine 336) were the most efficient supports for Au III extraction. The simultaneous extraction and reduction processes were proven to be the result of a synergic phenomenon in which all the membrane components were involved. Scanning electron microscopy characterization of cross-sectional samples suggested a distribution of AuNPs throughout the membrane. Transmission electron microscopy characterization of the AuNPs indicated average particle sizes of 36.7 and 2.9 nm for the PIMs and PNMs, respectively. AuNPs supported on PIMs allowed for >95.4 % reduction of a 0.05 mmol L -1 4-nitrophenol aqueous solution with 10 mmol L -1 NaBH 4 solution within 25 min., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Cd(II) transport from 1moldm(-3) HCl media was investigated across semi-interpenetrating hybrid membranes (SIHMs) that were prepared by mixing an organic matrix composed of ADOGEN(®) 364 as an extracting agent, cellulose triacetate as a polymeric support and nitrophenyloctyl ether as a plasticizer with an organic/inorganic network (silane phase, SP) composed of polydimethylsiloxane and a crosslinking agent. The stripping phase used was a 10(-2)mol dm(-3) ethanesulfonic acid solution. The effects of tetraorthoethoxysilane, phenyltrimethoxysilane and N',N'-bis[3-tri(methoxysilyl)propyl]ethylendiamine as crosslinking agents on the transport were studied. H3PO4 was used as an acid catalyst during the SP synthesis and optimized for transport performance. Solid-liquid extraction experiments were performed to determine the model that describe the transport of Cd(II) via ADOGEN(®) 364. The transport was found to be chained-carrier controlled with a percolation threshold of 0.094 mmol g(-1). The selective recovery of Cd(II) was studied with respect to Ni(II), Zn(II), Cu(II), and Pb(II) at a 1:1 molar ratio, and the optimized membrane system was applied for the recovery of Cd(II) from a real sample consisting of a Ni/Cd battery with satisfactory results. Finally, stability experiments were performed using the same membrane for 14 cycles. The results obtained showed that SIHMs had excellent stability and selectivity, with permeabilities comparable to those of PIMs., (Copyright © 2014 Elsevier B.V. All rights reserved.)