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Highlights • A facile synthetic route to copper sulfide in continuous Couette-Taylor reactor. • Morphology control of copper sulfide by level of supersaturation. • Level of supersaturation could be effectively regulated by rotational speed. Abstract In this report, a Couette-Taylor (CT) reactor was applied as an effective continuous process for synthesizing copper sulfide nanoparticles. The rotational speed, mean residence time (MRT), and concentration of the feed solution were important control factors on the morphology and size control of the nanoparticles. Increasing the rotational speed from 80 rpm to 90 rpm changed the morphology of the synthesized nanoparticles from nanofibers to hexagonal nanoplates. Only Cu 7 S 4 nanofibers were obtained in the batch reactor. Through various comparative experiments, we found that MRT and the feed solution concentration affect monomer concentration in the CT reactor, thus controlling the morphology and size of the nanoparticles. [ABSTRACT FROM AUTHOR]

(NH 4 )Fe 2 (PO 4 ) 2 (OH)·2H 2 O samples with different morphology are successfully synthesized via two-step synthesis route – ultrasonic-intensified impinging stream pre-treatment followed by hydrothermal treatment (UIHT) method. The effects of the adoption of ultrasonic-intensified impinging stream pre-treatment, reagent concentration ( C ), pH value of solution and hydrothermal reaction time ( T ) on the physical and chemical properties of the synthesised (NH 4 )Fe 2 (PO 4 ) 2 (OH)·2H 2 O composites and FePO 4 particles were systematically investigated. Nano-seeds were firstly synthesized using the ultrasonic-intensified T-mixer and these nano-seeds were then transferred into a hydrothermal reactor, heated at 170 °C for 4 h. The obtained samples were characterized by utilising XRD, BET, TG-DTA, SEM, TEM, Mastersizer 3000 and FTIR, respectively. The experimental results have indicated that the particle size and morphology of the obtained samples are remarkably affected by the use of ultrasonic-intensified impinging stream pre-treatment, hydrothermal reaction time, reagent concentration, and pH value of solution. When such (NH 4 )Fe 2 (PO 4 ) 2 (OH)·2H 2 O precursor samples were transformed to FePO 4 products after sintering at 650 °C for 10 h, the SEM images have clearly shown that both the precursor and the final product still retain their monodispersed spherical microstructures with similar particle size of about 3 μm when the samples are synthesised at the optimised condition. [ABSTRACT FROM AUTHOR]

Viability-PCR (vPCR) protocols are mainly based on photo-reactive dyes impermeant to intact cell membranes. The absence of cell barriers allows the reagent's interaction with the genetic material after a short incubation period. By light-induced reaction, DNA becomes the unsuitable mould for the polymerases and thus cannot be amplified and detected by PCR. General rules and consensus exist on critical aspects of successful vPCR protocol development. However, the understanding of the vPCR reaction concerning how much reagent is really effective or the proper amount of light has been poorly studied. The convenience of using 600 times more dye than bases pairs exist suggests that although these dyes are DNA intercalating reagents, many organic molecules can adsorb it. Concerning light, no exact references exist about how much energy is needed to activate the azide group of reagents such as propidium monoazide. Therefore, it cannot be calculated in terms of energy how much light needs a vPCR protocol. The general rule is to provide reagents and energy in excess. This work provides different responses (based on experimental results) to both questions, which can contribute to a better understanding of the theoretical basis of vPCR protocols. • The general rule for viability PCR (vPCR) protocols is to provide reagents and energy in excess. • The data suggest that although these reagents are DNA intercalating reagents, many organic molecules must be adsorbing them. • No exact references exist about how much energy is needed to activate the azide group of reagents such as PMA. • In this work, the light/energy balance allows a better understanding of the analytical ranges of the vPCR. • If a concentration of 50 μM of PMA is exceeded there may not be enough energy to activate all the reagent molecules. [ABSTRACT FROM AUTHOR]

Abstract: Advanced oxidation of an azo-dye, Direct Red 28 (DR 28) by photo-Fenton treatment was investigated in batch experiments using Box–Behnken statistical experiment design and the response surface analysis. Dyestuff (DR 28), H2O2 and Fe(II) concentrations were selected as independent variables in Box–Behnken design while color and total organic carbon (TOC) removal (mineralization) were considered as the response functions. Color removal increased with increasing H2O2 and Fe(II) concentrations up to a certain level. High concentrations of H2O2 and Fe(II) adversely affected the color and TOC removals due to hydroxyl radical scavenging effects of high oxidant and catalyst concentrations. Both H2O2 and Fe(II) concentration had profound effects on decolorization. Percent color removal was higher than TOC removal indicating formation of colorless organic intermediates. Complete color removal was achieved within 5min while complete mineralization took nearly 15min. The optimal reagent doses varied depending on the initial dyestuff dose. For the highest dyestuff concentration tested, the optimal H2O2/Fe(II)/dyestuff ratio resulting in the maximum color removal (100%) was predicted to be 715/71/250 (mgL−1), while this ratio was 1550/96.5/250 for maximum mineralization (97.5%). [Copyright &y& Elsevier]

The use of reagent concentration has resulted in increased rates for all stages of the REM resin synthesis of tertiary amines. These increases in rate translate into faster reaction times, higher yields and lower reagent consumption. Of the methods examined, the most successful was the use of perfluorous solvents, either alone or with a small amount of organic co-solvent. [Copyright &y& Elsevier]

The incorporation of 2,2,2-trifluoroethanol esters into substrates for the REM resin synthesis of 3° amines allows a one-pot Hofmann elimination/transesterification protocol to be performed. In this way α-amino acid esters and amides were synthesised by adding alcohols or 1° amines to the Hofmann elimination mixture. The excess of nucleophile required to drive the transesterification or amidation to completion was found to be considerably lower when perfluorous solvents were used to accelerate the reaction (FAST effect). [Copyright &y& Elsevier]

The use of extremely low solvent volumes (2 μL or less per mg resin) results in significant increases in yield for both the Diels–Alder and Heck reactions on solid-phase compared to standard high dilution techniques. [Copyright &y& Elsevier]