Cu(II)/Ag(I)-Catalyzed Cascade Reaction of Sulfonylhydrazone with Anthranils: Synthesis of 2‑Aryl-3-sulfonyl Substituted Quinoline Derivatives

In this paper, a Cu­(II)/Ag­(I)-catalyzed cascade reaction of anthranils with sulfonylhydrazone to construct 2-phenyl-3-sulfonyl disubstituted quinoline derivatives under mild conditions was studied. The mechanism study indicated that this reaction involves radical addition, and new C–C, C–N, and C–S bonds were constructed in one step

Effects of Transmembrane Hydraulic Pressure on Performance of Forward Osmosis Membranes

Forward osmosis (FO) is an emerging membrane separation process that continues to be tested and implemented in various industrial water and wastewater treatment applications. The growing interests in the technology have prompted laboratories and manufacturers to adopt standard testing methods to ensure accurate comparison of membrane performance under laboratory-controlled conditions; however, standardized methods might not capture specific operating conditions unique to industrial applications. Experiments with cellulose triacetate (CTA) and polyamide thin-film composite (TFC) FO membranes demonstrated that hydraulic transmembrane pressure (TMP), common in industrial operation of FO membrane elements, could affect membrane performance. Experiments were conducted with three FO membranes and with increasing TMP up to a maximum of 50 psi (3.45 bar). The feed solution was a mixture of salts and the draw solution was either a NaCl solution or concentrated seawater at similar osmotic pressure. Results revealed that TMP minimally affected water flux, reverse salt flux (RSF), and solute rejection of the CTA membrane. However, water flux through TFC membranes might slightly increase with increasing TMP, and RSF substantially declines with increasing TMP. It was observed that rejection of feed constituents was influenced by TMP and RSF

Enhancing Asymmetric Reduction of 3‑Chloropropiophenone with Immobilized <i>Acetobacter</i> sp. CCTCC M209061 Cells by Using Deep Eutectic Solvents as Cosolvents

Use of deep eutectic solvents (DESs) to improve biocatalytic asymmetric reduction of 3-chloropropiophenone to (<i>S</i>)-3-chloro-1-phenylpropanol catalyzed by whole-cell of Acetobacter sp. CCTCC M209061 was successfully performed. The cells immobilized on PVA-sodium sulfate exhibited markedly enhanced stability. Diverse DESs, as cosolvents, manifested significantly different influences on the reaction. Among them, the DES choline chloride/urea ([ChCl]­[U]) showed the best biocompatibility and moderately increased the cell member permeability, as demonstrated by MAR and flow cytometry assays, and consequently gave the best results. For the bioreduction conducted in the [ChCl]­[U]-containing system, the optimum [ChCl]­[U] content, substrate concentration, glucose concentration, pH and temperature were 5% (v/v), 10.0 mmol/L, 60 mmol/L, 5.5 and 30 °C, respectively. Under the optimized conditions, the obtained yield and product <i>e.e.</i> were 82.3% and above 99.0% at a reaction time of 6 h, respectively, and the productivity was 1.37 mmol/L/h. The efficient whole-cell biocatalytic process proved to be feasible on a 500 mL preparative scale. Moreover, the combination of water-immiscible ionic liquid C₄MIM·PF₆ with [ChCl]­[U] in a biphasic system further enhanced substrate concentration (16.0 mmol/L), product yield (93.3%) and productivity (1.87 mmol/L/h) significantly, showing to be very promising for biocatalytic synthesis of (<i>S</i>)-3-chloro-1-phenylpropanol with immobilized Acetobacter sp. CCTCC M209061 cells

Revealing the Mechanism of Photoluminescence from Single Gold Nanospheres by Defocused Imaging

The mechanism for the photoluminescence (PL) emission from gold nanoparticles has attracted considerable attention for many years. However, there is an important gap between small nanoclusters (∼2 nm) and larger plasmonic particles (∼50 nm). In this work, using defocused imaging technique, we investigate the PL properties of gold nanospheres (15–20 nm in diameter) on a single-particle level. Photoblinking and photobleaching phenomena are both observed. We notice that although these nanospheres can support surface plasmon resonance at ∼515 nm, they emit at ∼630 nm (excited by 532 nm), which is obviously plasmon-independent. The observed defocused images (DIs) exhibit isotropy first and then either transform into anisotropy or vanish rapidly. Surprisingly, the DIs can change their emission pattern within one single nanosphere during the tracing time. All these PL properties suggest a multiple-dipole-emission model. High-resolution transmission electron microscopy images demonstrate that these nanospheres are polycrystalline containing multiple small crystal domains (∼3 nm). We believe that these small domains divide the particle into different clusters and give rise to the photoblinking behavior and rotary DIs. The presented PL mechanism links gold nanoclusters and single-crystal nanorods, which could be helpful in understanding the origins of photoblinking and the luminescent properties from metallic nanoparticles. In addition, these water-soluble gold nanospheres provide new opportunities for biological labels and light-emitting sources in nanophotonics

Biocompatible Deep Eutectic Solvents Based on Choline Chloride: Characterization and Application to the Extraction of Rutin from Sophora japonica

The development of novel green solvents has been one of the hottest subjects in green chemistry. Deep eutectic solvents (DESs) have logically and naturally emerged in the search for more biocompatible and biodegradable solvents. In this study, some basic physical properties, including viscosity, conductivity, and density, of 20 DESs prepared from choline chloride and various hydrogen-bond donors were investigated systematically. In addition, the biocompatibility of the tested DESs was qualitatively and quantitatively evaluated using two Gram-positive (Staphylococcus aureus and Listeria monocytogenes) and two Gram-negative (Escherichia coli and Salmonella enteritidis) bacteria. A closed bottle test was used to assess the biodegradability of these DESs. The results demonstrated that these choline chloride-based DESs were excellent solvents with extremely low toxicity and favorable biodegradability. Finally, DESs were used to extract a flavonoid (rutin) from the flower buds of Sophora japonica. An extraction efficiency of 194.17 ± 2.31 mg·g^–1 was achieved using choline chloride/triethylene glycol containing 20% water. The excellent properties of DESs indicate their potential as promising green solvents for the extraction of rutin with favorable prospects for wide use in the field of green technology

Immune responses in the “PIV5 naïve” dogs inoculated with rPIV5-H3.

<p>The dog blood samples were collected at 0 and 21 days post infection. 4 HAU of the influenza A virus (A/Udorn/72, H3N2 subtype) were mixed with serially diluted dog sera in 96-well round-bottom plates. The hemagglutination inhibition (HAI) titer was scored as the reciprocal of the highest dilution antiserum that completely inhibits hemagglutination. The graph shows the mean value of duplicate wells for each dog. The limit of detection of the HAI titer (10) is indicated.</p